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Sample records for difference vegetation index

  1. The Generalized Difference Vegetation Index (GDVI) for Dryland Characterization

    OpenAIRE

    Weicheng Wu

    2014-01-01

    A large number of vegetation indices have been developed and widely applied in terrestrial ecosystem research in the recent decades. However, a certain limitation was observed while applying these indices in research in dry areas due to their low sensitivity to low vegetation cover. In this context, the objectives of this study are to develop a new vegetation index, namely, the Generalized Difference Vegetation Index (GDVI), and to examine its applicability to the assessment of dryland enviro...

  2. Comparison of Topographic Effects between the Enhanced Vegetation Index (EVI) and Normalized Difference Vegetation Index (NDVI)

    Science.gov (United States)

    Matsushita, B.; Yang, W.; Chen, J.; Onda, Y.

    2007-12-01

    Vegetation indices play an important role in monitoring variations in vegetation. The Enhanced Vegetation Index (EVI) proposed by the MODIS Land Discipline Group and the Normalized Difference Vegetation Index (NDVI) are both global-based vegetation indices aimed at providing consistent spatial and temporal information regarding global vegetation. However, many environmental factors such as atmospheric conditions and soil background may produce errors in these indices. The topographic effect is another very important factor, especially when the indices are used in areas of rough terrain. In this paper, we analyzed differences in the topographic effect between the EVI and the NDVI based on a non-Lambertian model and using two airborne-based images with a spatial resolution of 1.5m acquired from a mountainous area covered by a homogeneous Japanese cypress plantation. The results indicate that the soil adjustment factor "L" in the EVI makes it more sensitive to topographic conditions than is the NDVI. Based on these results, we strongly recommend that the topographic effect be removed from the EVI--as well as from other vegetation indices that similarly include a term without a band ratio format (e.g., the PVI and SAVI)--when these indices are used in conjunction with a high spatial resolution image of an area of rough terrain, where the topographic effect on the vegetarian indices having only a band ratio format (e.g., the NDVI) can usually be ignored.

  3. Relative sensitivity of Normalized Difference Vegetation Index (NDVI) and Microwave Polarization Difference Index (MPDI) for vegetation and desertification monitoring

    Science.gov (United States)

    Becker, Francois; Choudhury, Bhaskar J.

    1988-01-01

    A simple equation relating the Microwave Polarization Difference Index (MPDI) and the Normalized Difference Vegetation Index (NDVI) is proposed which represents well data obtained from Nimbus 7/SMMR at 37 GHz and NOAA/AVHRR Channels 1 and 2. It is found that there is a limit which is characteristic of a particular type of cover for which both indices are equally sensitive to the variation of vegetation, and below which MPDI is more efficient than NDVI. The results provide insight into the relationship between water content and chlorophyll absorption at pixel size scales.

  4. Evaluation of vegetation cover using the normalized difference vegetation index (NDVI

    Directory of Open Access Journals (Sweden)

    Gabriela Camargos Lima

    2013-08-01

    Full Text Available Soil loss by water erosion is the main cause of soil degradation in Brazil. However, erosion can be reduced by the presence of vegetation. The Normalized Difference Vegetation Index (NDVI makes it possible to identify the vegetative vigor of crops or natural vegetation which facilities the identification of areas with vegetation covers. This information is very important in identifying the phenomena which might be occurring in a particular area, especially those related to soil degradation by water erosion. Thus, the aim of this work was to assess the canopy cover by using NDVI, checking the image accuracy using the Coverage Index (CI based on the Stocking method, in the Sub-basin of Posses, which belongs to the Cantareira System, located in the Extrema municipality, Minas Gerais, Brazil. Landsat-5 TM images were used. The sub-basin of Posses was very altered in comparison to the surrounding areas. The NDVI technique proved to be a suitable tool to assess the uses that occur in the sub-basin of Posses, as validated by the Stocking methodology. The map derived from NDVI allowed the geographic distribution of different land uses to be observed and allowed for the identification of critical areas in relation to vegetation cover as well. This finding can be used to optimize efforts to recover and protect soil in areas with bare soil and degraded pasture, in order to reduce environmental degradation. The CI has not exceeded 40% for land use classes that occur in the majority of the sub-basin (91%, except in areas of woody vegetation.

  5. MODIS normalized difference vegetation index (NDVI) and vegetation phenology dynamics in the Inner Mongolia grassland

    Science.gov (United States)

    Gong, Z.; Kawamura, K.; Ishikawa, N.; Goto, M.; Wulan, T.; Alateng, D.; Yin, T.; Ito, Y.

    2015-11-01

    The Inner Mongolia grassland, one of the most important grazing regions in China, has long been threatened by land degradation and desertification, mainly due to overgrazing. To understand vegetation responses over the last decade, this study evaluated trends in vegetation cover and phenology dynamics in the Inner Mongolia grassland by applying a normalized difference vegetation index (NDVI) time series obtained by the Terra Moderate Resolution Imaging Spectroradiometer (MODIS) during 2002-2014. The results showed that the cumulative annual NDVI increased to over 77.10 % in the permanent grassland region (2002-2014). The mean value of the total change showed that the start of season (SOS) date and the peak vegetation productivity date of the season (POS) had advanced by 5.79 and 2.43 days, respectively. The end of season (EOS) was delayed by 5.07 days. These changes lengthened the season by 10.86 days. Our results also confirmed that grassland changes are closely related to spring precipitation and increasing temperature at the early growing period because of global warming. Overall, productivity in the Inner Mongolia Autonomous Region tends to increase, but in some grassland areas with grazing, land degradation is ongoing.

  6. NOAA Climate Data Record (CDR) of Normalized Difference Vegetation Index (NDVI), Version 4

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains gridded daily Normalized Difference Vegetation Index (NDVI) derived from the NOAA Climate Data Record (CDR) of Advanced Very High Resolution...

  7. Elk Distributions Relative to Spring Normalized Difference Vegetation Index Values

    International Nuclear Information System (INIS)

    Rocky Mountain elk (Cervus elaphus) that winter near San Antonio Mountain in northern New Mexico provide important recreational and economic benefits while creating management challenges related to temporospatial variation in their spring movements. Our objective was to examine spring distributions of elk in relation to vegetative emergence as it progresses across the landscape as measured by remote sensing. Spring distributions of elk were closely associated with greater photosynthetic activity of spring vegetation in 2 of 3 years as determined using NDVI values derived from AVHRR datasets. Observed elk locations were up to 271% greater than expected in the category representing the most photosynthetic activity. This association was not observed when analyses at a finer geographic scale were conducted. Managers facing challenges involving human-wildlife interactions and land-use issues should consider environmental conditions that may influence variation in elk association with greener portions of the landscape.

  8. Determination of Leaf Area Index, Total Foliar N, and Normalized Difference Vegetation Index for Arctic Ecosystems Dominated by Cassiope tetragona

    DEFF Research Database (Denmark)

    Campioli, M; Street, LE; Michelsen, Anders; Shaver, GR; Maere, T; Samson, R; Lemeur, R

    2009-01-01

    have not been accurately quantified. We address this knowledge gap by (i) direct measurements of LAI and TFN for C. tetragona, and (ii) determining TFN-LAI and LAI–normalized difference vegetation index (NDVI) relationships for typical C. tetragona tundras in the subarctic (Sweden) and High Arctic...... leaf N and biomass. The LAI-NDVI and TFN-LAI relationships showed high correlation and can be used to estimate indirectly LAI and TFN. The LAI-NDVI relationship for C. tetragona vegetation differed from a generic LAI-NDVI relationship for arctic tundra, whereas the TFN-LAI relationship did not. Overall......Leaf area index (LAI) and total foliar nitrogen (TFN) are important canopy characteristics and crucial variables needed to simulate photosynthesis and ecosystem CO2 fluxes. Although plant communities dominated by Cassiope tetragona are widespread in the Arctic, LAI and TFN for this vegetation type...

  9. Normalized difference vegetation index (NDVI) in the management of mountain meadows.

    Czech Academy of Sciences Publication Activity Database

    Mašková, Z.; Zemek, František; Kv?t, Jan

    2008-01-01

    Ro?. 13, - (2008), s. 417-432. ISSN 1239-6095 R&D Projects: GA ?R(CZ) GA206/99/1410 Institutional research plan: CEZ:AV0Z60870520 Keywords : normalized difference vegetation index * mountain medows * mulching Subject RIV: EH - Ecology, Behaviour Impact factor: 1.620, year: 2008 www.borenv.net

  10. Forest leaf area index determination : a multiyear satelliteindependent method based on within-stand normalized difference vegetation index spatial variability

    OpenAIRE

    le Maire, G.; François, C.; Soudani, Kamel; Davi, H.; Le Dantec, V.; Saugier, Bernard; Dufrene, E.

    2006-01-01

    The Leaf Area Index (LAI) and its spatial distribution are key features to describe the forest ecophysiological processes. A stable and reproducible relationship is obtained between the LAI and the standard deviation sNDVI of the pixel-based satellite-derived normalized difference vegetation indices (NDVI) of forest stands. In situ measurements of LAI have been performed with the LAI-2000 Plant Canopy Analyser over 8 years in the managed Fontainebleau forest (France) on about 31 stands each y...

  11. Establishment of empirical relations between fuel moisture content and the normalised difference vegetation index

    Scientific Electronic Library Online (English)

    M, Castro; J.C, Parra; L. J, Morales; C, Salas.

    2014-09-01

    Full Text Available The object of the present research is to establish empirical relations between the Fuel Moisture Content (FMC) and the Normalised Difference Vegetation Index (NDVI) in pasture samples. The study area was the Carillanca Experimental Centre belonging to the Institute ofAgriculture and Livestock Resear [...] ch (Instituto de Investigaciones Agropecuarias - INIA), Araucanía Region, Chile. The study period ran from November 2011 to January 2012, in order to determine the variation in vegetation moisture content from spring, when plant cover is most vigorous, to summer when it declines to a minimum due to the summer drought. The application of a linear adjustment model produced correlation coefficients higher than 0.6.

  12. Spatiotemporal variability and predictability of Normalized Difference Vegetation Index (NDVI) in Alberta, Canada

    Science.gov (United States)

    Jiang, Rengui; Xie, Jiancang; He, Hailong; Kuo, Chun-Chao; Zhu, Jiwei; Yang, Mingxiang

    2016-01-01

    As one of the most popular vegetation indices to monitor terrestrial vegetation productivity, Normalized Difference Vegetation Index (NDVI) has been widely used to study the plant growth and vegetation productivity around the world, especially the dynamic response of vegetation to climate change in terms of precipitation and temperature. Alberta is the most important agricultural and forestry province and with the best climatic observation systems in Canada. However, few studies pertaining to climate change and vegetation productivity are found. The objectives of this paper therefore were to better understand impacts of climate change on vegetation productivity in Alberta using the NDVI and provide reference for policy makers and stakeholders. We investigated the following: (1) the variations of Alberta's smoothed NDVI (sNDVI, eliminated noise compared to NDVI) and two climatic variables (precipitation and temperature) using non-parametric Mann-Kendall monotonic test and Thiel-Sen's slope; (2) the relationships between sNDVI and climatic variables, and the potential predictability of sNDVI using climatic variables as predictors based on two predicted models; and (3) the use of a linear regression model and an artificial neural network calibrated by the genetic algorithm (ANN-GA) to estimate Alberta's sNDVI using precipitation and temperature as predictors. The results showed that (1) the monthly sNDVI has increased during the past 30 years and a lengthened growing season was detected; (2) vegetation productivity in northern Alberta was mainly temperature driven and the vegetation in southern Alberta was predominantly precipitation driven for the period of 1982-2011; and (3) better performances of the sNDVI-climate relationships were obtained by nonlinear model (ANN-GA) than using linear (regression) model. Similar results detected in both monthly and summer sNDVI prediction using climatic variables as predictors revealed the applicability of two models for different period of year ecologists might focus on.

  13. Higher northern latitude normalized difference vegetation index and growing season trends from 1982 to 1999.

    Science.gov (United States)

    Tucker, C J; Slayback, D A; Pinzon, J E; Los, S O; Myneni, R B; Taylor, M G

    2001-11-01

    Normalized difference vegetation index data from the polar-orbiting National Oceanic and Atmospheric Administration meteorological satellites from 1982 to 1999 show significant variations in photosynthetic activity and growing season length at latitudes above 35 degrees N. Two distinct periods of increasing plant growth are apparent: 1982-1991 and 1992-1999, separated by a reduction from 1991 to 1992 associated with global cooling resulting from the volcanic eruption of Mt. Pinatubo in June 1991. The average May to September normalized difference vegetation index from 45 degrees N to 75 degrees N increased by 9% from 1982 to 1991, decreased by 5% from 1991 to 1992, and increased by 8% from 1992 to 1999. Variations in the normalized difference vegetation index were associated with variations in the start of the growing season of -5.6, +3.9, and -1.7 days respectively, for the three time periods. Our results support surface temperature increases within the same period at higher northern latitudes where temperature limits plant growth. PMID:11769318

  14. Vegetation Drought Response Index

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — VegDRI, short for Vegetation Drought Response Index, is a drought-monitoring tool developed by scientists at EROS in collaboration with the National Drought...

  15. Comparison of Normalized Burn Ratio, Normalized Difference Vegetation Index, and Enhanced Vegetation Index in Areas Burned by the Jasper Wildfire of Black Hills South Dakota

    Science.gov (United States)

    Chen, X.; Zhu, Z.

    2007-12-01

    The Jasper wildfire of August and September 2000 was the largest fire to occur in the Black Hills in at least a century. The disturbance on ecosystem characteristics will be widespread and long-term. Monitoring postfire vegetation changes using remote sensing data can provide unique and timely information about ecosystem dynamics. In this study, the Normalized Burn Ratio (NBR), Normalized Difference Vegetation Index (NDVI), and Enhanced Vegetation Index (EVI) data were derived from Landsat imagery and compared before and after the Jasper fire. Landsat 5 images acquired on June 2, 2000 (preburn), and June 5, 2001 (10 months postburn), were analyzed. In addition, a Landsat 7 image acquired on May 31, 2002 (22 months postburn), was used in the study. Landsat data were converted to at-sensor reflectance, and NBR, NDVI, and EVI values were calculated for low, moderate, and high burn severity areas defined by using the difference of NBR between 2001 and 2000. NBR values in areas characterized as low burn severity changed very little between 2001 and 2002. Meanwhile, areas characterized as moderate or high severity showed substantial increases in NBR values between 2001 and 2002, implying some ecosystem recovery occurring for these areas over a relatively short time. EVI and NDVI show similar patterns of change, but it was found that EVI and NBR indices are more sensitive than is NDVI for capturing vegetation cover changes during the early postfire years. Further research is planned to use Landsat and MODIS imagery to assess spectral trends as a function of time in areas affected by fire.

  16. On the characterization of vegetation recovery after fire disturbance using Fisher-Shannon analysis and SPOT/VEGETATION Normalized Difference Vegetation Index (NDVI) time series

    Science.gov (United States)

    Lasaponara, Rosa; Lanorte, Antonio; Lovallo, Michele; Telesca, Luciano

    2015-04-01

    Time series can fruitfully support fire monitoring and management from statistical analysis of fire occurrence (Tuia et al. 2008) to danger estimation (lasaponara 2005), damage evaluation (Lanorte et al 2014) and post fire recovery (Lanorte et al. 2014). In this paper, the time dynamics of SPOT-VEGETATION Normalized Difference Vegetation Index (NDVI) time series are analyzed by using the statistical approach of the Fisher-Shannon (FS) information plane to assess and monitor vegetation recovery after fire disturbance. Fisher-Shannon information plane analysis allows us to gain insight into the complex structure of a time series to quantify its degree of organization and order. The analysis was carried out using 10-day Maximum Value Composites of NDVI (MVC-NDVI) with a 1 km × 1 km spatial resolution. The investigation was performed on two test sites located in Galizia (North Spain) and Peloponnese (South Greece), selected for the vast fires which occurred during the summer of 2006 and 2007 and for their different vegetation covers made up mainly of low shrubland in Galizia test site and evergreen forest in Peloponnese. Time series of MVC-NDVI have been analyzed before and after the occurrence of the fire events. Results obtained for both the investigated areas clearly pointed out that the dynamics of the pixel time series before the occurrence of the fire is characterized by a larger degree of disorder and uncertainty; while the pixel time series after the occurrence of the fire are featured by a higher degree of organization and order. In particular, regarding the Peloponneso fire, such discrimination is more evident than in the Galizia fire. This suggests a clear possibility to discriminate the different post-fire behaviors and dynamics exhibited by the different vegetation covers. Reference Lanorte A, R Lasaponara, M Lovallo, L Telesca 2014 Fisher-Shannon information plane analysis of SPOT/VEGETATION Normalized Difference Vegetation Index (NDVI) time series to characterize vegetation recovery after fire disturbanceInternational Journal of Applied Earth Observation and Geoinformation 26 441-446 Lanorte A, M Danese, R Lasaponara, B Murgante 2014 Multiscale mapping of burn area and severity using multisensor satellite data and spatial autocorrelation analysis International Journal of Applied Earth Observation and Geoinformation 20, 42-51 Tuia D, F Ratle, R Lasaponara, L Telesca, M Kanevski 2008 Scan statistics analysis of forest fire clusters Communications in Nonlinear Science and Numerical Simulation 13 (8), 1689-1694 Telesca L, R Lasaponara 2006 Pre and post fire behavioral trends revealed in satellite NDVI time series Geophysical Research Letters 33 (14) Lasaponara R 2005 Intercomparison of AVHRR based fire susceptibility indicators for the Mediterranean ecosystems of southern Italy International Journal of Remote Sensing 26 (5), 853-870

  17. Avaliação da cobertura vegetal pelo índice de vegetação por diferença normalizada (IVDN) / Evaluation of vegetation cover using the normalized difference vegetation index (NDVI)

    Scientific Electronic Library Online (English)

    Gabriela Camargos, Lima; Marx Leandro Naves, Silva; Nilton, Curi; Mayesse Aparecida da, Silva; Anna Hoffmann, Oliveira; Junior Cesar, Avanzi; Marta Eichemberger, Ummus.

    2013-08-01

    Full Text Available A perda de solo por erosão hídrica é a principal causa da degradação do solo no Brasil. No entanto, a erosão pode ser reduzida pela presença da vegetação. O cálculo do Índice de Vegetação por Diferença Normalizada (IVDN) permite avaliar o vigor vegetativo de culturas ou vegetação natural o que facil [...] ita a identificação de áreas com cobertura vegetal. Esta informação é muito importante para identificar o fenômeno que pode estar ocorrendo em uma determinada área, especialmente aqueles relacionados à degradação do solo por erosão hídrica. Assim, o objetivo deste trabalho foi avaliar o índice de cobertura vegetal por IVDN e verificar a precisão utilizando o Índice de Cobertura (IC) de Stocking, na sub-bacia das Posses, a qual pertence ao Sistema Cantareira, localizada no município de Extrema, Minas Gerais, Brasil. Para tanto, utilizou-se as imagens Landsat-5 TM. A sub-bacia das Posses mostrou-se alterada quando comparada com a área de entorno. A técnica do IVDN mostrou-se com boa acurácia para identificar os usos que ocorrem na sub-bacia das Posses, sendo validados pela metodologia de Stocking. O mapeamento pelo IVDN permitiu localizar na sub-bacia a distribuição geográfica dos diferentes usos do solo e identificar as áreas críticas em relação à cobertura vegetal, e, assim planejar esforços para recuperação e proteção do solo nas áreas desnudas e com pastagem degradada, visando diminuição dos passivos ambientais. O IC não ultrapassou 40% para a maioria dos usos que ocorrem na sub-bacia (91%), excetuando as áreas de vegetação arbórea. Abstract in english Soil loss by water erosion is the main cause of soil degradation in Brazil. However, erosion can be reduced by the presence of vegetation. The Normalized Difference Vegetation Index (NDVI) makes it possible to identify the vegetative vigor of crops or natural vegetation which facilities the identifi [...] cation of areas with vegetation covers. This information is very important in identifying the phenomena which might be occurring in a particular area, especially those related to soil degradation by water erosion. Thus, the aim of this work was to assess the canopy cover by using NDVI, checking the image accuracy using the Coverage Index (CI) based on the Stocking method, in the Sub-basin of Posses, which belongs to the Cantareira System, located in the Extrema municipality, Minas Gerais, Brazil. Landsat-5 TM images were used. The sub-basin of Posses was very altered in comparison to the surrounding areas. The NDVI technique proved to be a suitable tool to assess the uses that occur in the sub-basin of Posses, as validated by the Stocking methodology. The map derived from NDVI allowed the geographic distribution of different land uses to be observed and allowed for the identification of critical areas in relation to vegetation cover as well. This finding can be used to optimize efforts to recover and protect soil in areas with bare soil and degraded pasture, in order to reduce environmental degradation. The CI has not exceeded 40% for land use classes that occur in the majority of the sub-basin (91%), except in areas of woody vegetation.

  18. Using normalized difference vegetation index to estimate carbon fluxes from small rotationally grazed pastures

    Science.gov (United States)

    Skinner, R.H.; Wylie, B.K.; Gilmanov, T.G.

    2011-01-01

    Satellite-based normalized difference vegetation index (NDVI) data have been extensively used for estimating gross primary productivity (GPP) and yield of grazing lands throughout the world. However, the usefulness of satellite-based images for monitoring rotationally-grazed pastures in the northeastern United States might be limited because paddock size is often smaller than the resolution limits of the satellite image. This research compared NDVI data from satellites with data obtained using a ground-based system capable of fine-scale (submeter) NDVI measurements. Gross primary productivity was measured by eddy covariance on two pastures in central Pennsylvania from 2003 to 2008. Weekly 250-m resolution satellite NDVI estimates were also obtained for each pasture from the moderate resolution imaging spectroradiometer (MODIS) sensor. Ground-based NDVI data were periodically collected in 2006, 2007, and 2008 from one of the two pastures. Multiple-regression and regression-tree estimates of GPP, based primarily on MODIS 7-d NDVI and on-site measurements of photosynthetically active radiation (PAR), were generally able to predict growing-season GPP to within an average of 3% of measured values. The exception was drought years when estimated and measured GPP differed from each other by 11 to 13%. Ground-based measurements improved the ability of vegetation indices to capture short-term grazing management effects on GPP. However, the eMODIS product appeared to be adequate for regional GPP estimates where total growing-season GPP across a wide area would be of greater interest than short-term management-induced changes in GPP at individual sites.

  19. Estimating Sahelian and East African soil moisture using the Normalized Difference Vegetation Index

    Science.gov (United States)

    McNally, A.; Funk, C.; Husak, G. J.; Michaelsen, J.; Cappelaere, B.; Demarty, J.; Pellarin, T.; Young, T. P.; Caylor, K. K.; Riginos, C.; Veblen, K. E.

    2013-06-01

    Rainfall gauge networks in Sub-Saharan Africa are inadequate for assessing Sahelian agricultural drought, hence satellite-based estimates of precipitation and vegetation indices such as the Normalized Difference Vegetation Index (NDVI) provide the main source of information for early warning systems. While it is common practice to translate precipitation into estimates of soil moisture, it is difficult to quantitatively compare precipitation and soil moisture estimates with variations in NDVI. In the context of agricultural drought early warning, this study quantitatively compares rainfall, soil moisture and NDVI using a simple statistical model to translate NDVI values into estimates of soil moisture. The model was calibrated using in-situ soil moisture observations from southwest Niger, and then used to estimate root zone soil moisture across the African Sahel from 2001-2012. We then used these NDVI-soil moisture estimates (NSM) to quantify agricultural drought, and compared our results with a precipitation-based estimate of soil moisture (the Antecedent Precipitation Index, API), calibrated to the same in-situ soil moisture observations. We also used in-situ soil moisture observations in Mali and Kenya to assess performance in other water-limited locations in sub Saharan Africa. The separate estimates of soil moisture were highly correlated across the semi-arid, West and Central African Sahel, where annual rainfall exhibits a uni-modal regime. We also found that seasonal API and NDVI-soil moisture showed high rank correlation with a crop water balance model, capturing known agricultural drought years in Niger, indicating that this new estimate of soil moisture can contribute to operational drought monitoring. In-situ soil moisture observations from Kenya highlighted how the rainfall-driven API needs to be recalibrated in locations with multiple rainy seasons (e.g., Ethiopia, Kenya, and Somalia). Our soil moisture estimates from NDVI, on the other hand, performed well in Niger, Mali and Kenya. This suggests that the NDVI-soil moisture relationship may be more robust across rainfall regimes than the API because the relationship between NDVI and plant available water is less reliant on local characteristics (e.g., infiltration, runoff, evaporation) than the relationship between rainfall and soil moisture.

  20. Simulating Visible/Infrared Imager Radiometer Suite Normalized Difference Vegetation Index Data Using Hyperion and MODIS

    Science.gov (United States)

    Ross, K. W.; Ryan, R. E.; Russell, J.

    2006-12-01

    The success of MODIS (the Moderate Resolution Imaging Spectrometer) in creating unprecedented, timely, high-quality data for vegetation and other studies has created great anticipation for data from VIIRS (the Visible/Infrared Imager Radiometer Suite). VIIRS will be carried onboard the joint NASA/Department of Defense/National Oceanic and Atmospheric Administration NPP (NPOESS (National Polar-orbiting Operational Environmental Satellite System) Preparatory Project). Because the VIIRS instruments will have lower spatial resolution than the current MODIS instruments--400 m versus 250 m--at nadir for the channels used to generate Normalized Difference Vegetation Index data, scientists need the answer to this question: how will the change in resolution affect vegetation studies? By using simulated VIIRS measurements, this question may be answered before the VIIRS instruments are deployed in space. Using simulated VIIRS products, the U.S. Department of Agriculture and other operational agencies can then modify their decision support systems appropriately in preparation for receipt of actual VIIRS data. VIIRS simulations and validations will be based on the ART (Application Research Toolbox), an integrated set of algorithms and models developed in MATLAB® that enables users to perform a suite of simulations and statistical trade studies on remote sensing systems. Specifically, the ART provides the capability to generate simulated multispectral image products, at various scales, from high spatial hyperspectral and/or multispectral image products. The ART uses acquired ("real") or synthetic datasets, along with sensor specifications, to create simulated datasets. For existing multispectral sensor systems, the simulated data products are used for comparison, verification, and validation of the simulated system's actual products. VIIRS simulations will be performed using Hyperion and MODIS datasets. The hyperspectral and hyperspatial properties of Hyperion data will be used to produce simulated MODIS and VIIRS products. Hyperion-derived MODIS data will be compared with near-coincident MODIS collects to validate both spectral and spatial synthesis, which will ascertain the accuracy of converting from MODIS to VIIRS. MODIS-derived VIIRS data is needed for global coverage and for the generation of time series for regional and global investigations. These types of simulations will have errors associated with aliasing for some scene types. This study will help quantify these errors and will identify cases where high quality, MODIS- derived VIIRS data will be available.

  1. Estimating Sugarcane Yield Potential Using an In-Season Determination of Normalized Difference Vegetative Index

    Directory of Open Access Journals (Sweden)

    Howard Viator

    2012-06-01

    Full Text Available Estimating crop yield using remote sensing techniques has proven to be successful. However, sugarcane possesses unique characteristics; such as, a multi-year cropping cycle and plant height-limiting for midseason fertilizer application timing. Our study objective was to determine if sugarcane yield potential could be estimated using an in-season estimation of normalized difference vegetative index (NDVI. Sensor readings were taken using the GreenSeeker® handheld sensor from 2008 to 2011 in St. Gabriel and Jeanerette, LA, USA. In-season estimates of yield (INSEY values were calculated by dividing NDVI by thermal variables. Optimum timing for estimating sugarcane yield was between 601–750 GDD. In-season estimated yield values improved the yield potential (YP model compared to using NDVI. Generally, INSEY value showed a positive exponential relationship with yield (r2 values 0.48 and 0.42 for cane tonnage and sugar yield, respectively. When models were separated based on canopy structure there was an increase the strength of the relationship for the erectophile varieties (r2 0.53 and 0.47 for cane tonnage and sugar yield, respectively; however, the model for planophile varieties weakened slightly. Results of this study indicate using an INSEY value for predicting sugarcane yield shows potential of being a valuable management tool for sugarcane producers in Louisiana.

  2. Global Trends in Seasonality of Normalized Difference Vegetation Index (NDVI, 1982–2011

    Directory of Open Access Journals (Sweden)

    Assaf Anyamba

    2013-09-01

    Full Text Available A 30-year series of global monthly Normalized Difference Vegetation Index (NDVI imagery derived from the Global Inventory Modeling and Mapping Studies (GIMMS NDVI3g archive was analyzed for the presence of trends in changing seasonality. Using the Seasonal Trend Analysis (STA procedure, over half (56.30% of land surfaces were found to exhibit significant trends. Almost half (46.10% of the significant trends belonged to three classes of seasonal trends (or changes. Class 1 consisted of areas that experienced a uniform increase in NDVI throughout the year, and was primarily associated with forested areas, particularly broadleaf forests. Class 2 consisted of areas experiencing an increase in the amplitude of the annual seasonal signal whereby increases in NDVI in the green season were balanced by decreases in the brown season. These areas were found primarily in grassland and shrubland regions. Class 3 was found primarily in the Taiga and Tundra biomes and exhibited increases in the annual summer peak in NDVI. While no single attribution of cause could be determined for each of these classes, it was evident that they are primarily found in natural areas (as opposed to anthropogenic land cover conversions and that they are consistent with climate-related ameliorations of growing conditions during the study period.

  3. Rural cases of equine West Nile virus encephalomyelitis and the normalized difference vegetation index

    Science.gov (United States)

    Ward, M.P.; Ramsay, B.H.; Gallo, K.

    2005-01-01

    Data from an outbreak (August to October, 2002) of West Nile virus (WNV) encephalomyelitis in a population of horses located in northern Indiana was scanned for clusters in time and space. One significant (p = 0.04) cluster of case premises was detected, occurring between September 4 and 10 in the south-west part of the study area (85.70??N, 45.50??W). It included 10 case premises (3.67 case premises expected) within a radius of 2264 m. Image data were acquired by the Advanced Very High Resolution Radiometer (AVHRR) sensor onboard a National Oceanic and Atmospheric Administration polar-orbiting satellite. The Normalized Difference Vegetation Index (NDVI) was calculated from visible and near-infrared data of daily observations, which were composited to produce a weekly-1km2 resolution raster image product. During the epidemic, a significant (p<0.01) decrease (0.025 per week) in estimated NDVI was observed at all case and control premise sites. The median estimated NDVI (0.659) for case premises within the cluster identified was significantly (p<0.01) greater than the median estimated NDVI for other case (0.571) and control (0.596) premises during the same period. The difference in median estimated NDVI for case premises within this cluster, compared to cases not included in this cluster, was greatest (5.3% and 5.1%, respectively) at 1 and 5 weeks preceding occurrence of the cluster. The NDVI may be useful for identifying foci of WNV transmission. ?? Mary Ann Liebert, Inc.

  4. The effect of water vapour on the normalized difference vegetation index derived for the Sahelian region from NOAA AVHRR data

    Science.gov (United States)

    Justice, Christopher O.; Eck, T. F.; Tanre, Didier; Holben, B. N.

    1991-01-01

    The near-infrared channel of the NOAA advanced very high resolution radiometer (AVHRR) contains a water vapor absorption band that affects the determination of the normalized difference vegetation index (NDVI). Daily and seasonal variations in atmospheric water vapor within the Sahel are shown to affect the use of the NDVI for the estimation of primary production. This water vapor effect is quantified for the Sahel by radiative transfer modeling and empirically using observations made in Mali in 1986.

  5. Models for the prediction of the cetane index of biofuels obtained from different vegetable oils using their fatty acid composition

    International Nuclear Information System (INIS)

    The objective of the present work is to obtain a physical-mathematical model that establishes a relationship between the cetane index of biofuels obtained from different vegetable oils and its composition of essential fatty acid. This model is based on experimental data obtained by the authors of the present work and an experimental data reported by different extracted authors of indexed databases. The adjustment of the coefficients of the model is based on the obtaining of residual minima in the capacity of prediction of the model. Starting from these results it is established a very useful tool for the determination of such an important parameter for the fuel diesel as it is the cetane index obtained from an analysis of chemical composition and not obtained from tests in engines banks, to save time and economic resources. (author)

  6. Estimating net ecosystem exchange of carbon using the normalized difference vegetation index and an ecosystem model

    International Nuclear Information System (INIS)

    The evaluation and prediction of changes in carbon dynamics at the ecosystem level is a key issue in studies of global change. An operational concept for the determination of carbon fluxes for the Belgian territory is the goal of the presented study. The approach is based on the integration of remotely sensed data into ecosystem models in order to evaluate photosynthetic assimilation and net ecosystem exchange (NEE). Remote sensing can be developed as an operational tool to determine the fraction of absorbed photosynthetically active radiation (feAR). A review of the methodological approach of mapping fPAR dynamics at the regional scale by means of NOAA11-A VHRR / 2 data for the year 1990 is given. The processing sequence from raw radiance values to fPAR is presented. An interesting aspect of incorporating remote sensing derived fPAR in ecosystem models is the potential for modeling actual as opposed to potential vegetation. Further work should prove whether the concepts presented and the assumptions made in this study are valid. (NEE). Complex ecosystem models with a highly predictive value for a specific ecosystem are generally not suitable for global or regional applications, since they require a substantial set of ancillary data becoming increasingly larger with increasing complexity of the model. The ideal model for our purpose is one that is simple enough to be used in global scale modeling, and which can be adapted for different ecosystems or vegetation types. The fraction of absorbed photosynthetically active radiation (fPAR) during the growing season determines in part net photosynthesis and phytomass production (Ruimy, 1995). Remotely measured red and near-infrared spectral reflectances can be used to estimate fPAR. Therefore, a possible approach is to estimate net photosynthesis, phytomass, and NEE from a combination of satellite data and an ecosystem model that includes carbon dynamics. It has to be stated that some parts of the work presented in this publication are a description of concepts. Other parts are descriptions of methodology and case studies of the concepts developed. (author)

  7. Spectra and vegetation index variations in moss soil crust in different seasons, and in wet and dry conditions

    Science.gov (United States)

    Fang, Shibo; Yu, Weiguo; Qi, Yue

    2015-06-01

    Similar to vascular plants, non-vascular plant mosses have different periods of seasonal growth. There has been little research on the spectral variations of moss soil crust (MSC) over different growth periods. Few studies have paid attention to the difference in spectral characteristics between wet MSC that is photosynthesizing and dry MSC in suspended metabolism. The dissimilarity of MSC spectra in wet and dry conditions during different seasons needs further investigation. In this study, the spectral reflectance of wet MSC, dry MSC and the dominant vascular plant (Artemisia) were characterized in situ during the summer (July) and autumn (September). The variations in the normalized difference vegetation index (NDVI), biological soil crust index (BSCI) and CI (crust index) in different seasons and under different soil moisture conditions were also analyzed. It was found that (1) the spectral characteristics of both wet and dry MSCs varied seasonally; (2) the spectral features of wet MSC appear similar to those of the vascular plant, Artemisia, whether in summer or autumn; (3) both in summer and in autumn, much higher NDVI values were acquired for wet than for dry MSC (0.6 ∼ 0.7 vs. 0.3 ∼ 0.4 units), which may lead to misinterpretation of vegetation dynamics in the presence of MSC and with the variations in rainfall occurring in arid and semi-arid zones; and (4) the BSCI and CI values of wet MSC were close to that of Artemisia in both summer and autumn, indicating that BSCI and CI could barely differentiate between the wet MSC and Artemisia.

  8. Correlation between normalized difference vegetation index and malaria in a subtropical rain forest undergoing rapid anthropogenic alteration

    Directory of Open Access Journals (Sweden)

    Nicole M. Wayant

    2010-05-01

    Full Text Available Time-series of coarse-resolution greenness values derived through remote sensing have been used as a surrogate environmental variable to help monitor and predict occurrences of a number of vector-borne and zoonotic diseases, including malaria. Often, relationships between a remotely-sensed index of greenness, e.g. the normalized difference vegetation index (NDVI, and disease occurrence are established using temporal correlation analysis. However, the strength of these correlations can vary depending on type and change of land cover during the period of record as well as inter-annual variations in the climate drivers (precipitation, temperature that control the NDVI values. In this paper, the correlation between a long (260 months time-series of monthly disease case rates and NDVI values derived from the Global Inventory Modeling and Mapping Studies (GIMMS data set were analysed for two departments (administrative units located in the Atlantic Forest biome of eastern Paraguay. Each of these departments has undergone extensive deforestation during the period of record and our analysis considers the effect on correlation of active versus quiescent periods of case occurrence against a background of changing land cover. Our results show that time-series data, smoothed using the Fourier Transform tool, showed the best correlation. A moving window analysis suggests that four years is the optimum time frame for correlating these values, and the strength of correlation depends on whether it is an active or a quiescent period. Finally, a spatial analysis of our data shows that areas where land cover has changed, particularly from forest to non-forest, are well correlated with malaria case rates.

  9. Correlation of meteorological parameters and remotely sensed normalized difference vegetation index (NDVI) with cotton leaf curl virus (CLCV) in Multan

    International Nuclear Information System (INIS)

    Climate change and weather has a profound effect on the spread of Cotton Leaf Curl Virus (CLCV) which is transmitted by whitefly. Climate change is altering temperature and precipitation patterns, resulting in the shift of some insect/pest from small population to large population thus effecting crops yield. To find out the relationship between the weather conditions, outburst of CLCV and changes in Normalized Difference Vegetation Index (NDVI) values due to the outburst of CLCV, a study was carried out for tehsil Multan. Data was acquired for the months of June, July, August and September for the year 2010. Regression analysis between CLCV and meteorological conditions as well as between CLCV and NDVI was performed. Meteorological parameters included temperature, humidity, precipitation, cloud cover, wind direction, pan evaporation and sunshine hours. NDVI values were calculated from SPOT satellite imagery (1km) using ArcMap10 and WinDisp v5.1. Correlation coefficients obtained in most of the cases were acceptable however the significance F and P-value were higher than their critical value at 95% level of significance. Therefore significant correlation was found only between CLCV and temperature and between CLCV and PAN evaporation during the month of July.

  10. Evaluation of the relation between evapotranspiration and normalized difference vegetation index for downscaling the simplified surface energy balance model

    Science.gov (United States)

    Haynes, Jonathan V.; Senay, Gabriel B.

    2012-01-01

    The Simplified Surface Energy Balance (SSEB) model uses satellite imagery to estimate actual evapotranspiration (ETa) at 1-kilometer resolution. SSEB ETa is useful for estimating irrigation water use; however, resolution limitations restrict its use to regional scale applications. The U.S. Geological Survey investigated the downscaling potential of SSEB ETa from 1 kilometer to 250 meters by correlating ETa with the Normalized Difference Vegetation Index (NDVI) from the Moderate Resolution Imaging Spectroradiometer instrument (MODIS). Correlations were studied in three arid to semiarid irrigated landscapes of the Western United States (Escalante Valley near Enterprise, Utah; Palo Verde Valley near Blythe, California; and part of the Columbia Plateau near Quincy, Washington) during several periods from 2002 to 2008. Irrigation season ETa-NDVI correlations were lower than expected, ranging from R2 of 0.20 to 0.61 because of an eastward 2-3 kilometer shift in ETa data. The shift is due to a similar shift identified in the land-surface temperature (LST) data from the MODIS Terra satellite, which is used in the SSEB model. Further study is needed to delineate the Terra LST shift, its effect on SSEB ETa, and the relation between ETa and NDVI.

  11. Comparative analysis of SPOT, Landsat, MODIS, and AVHRR normalized difference vegetation index data on the estimation of leaf area index in a mixed grassland ecosystem

    Science.gov (United States)

    Tong, Alexander; He, Yuhong

    2013-01-01

    Many grassland studies have depended on or are currently depending on the Landsat series of satellite sensors for monitoring work. However, given the identified gaps in Landsat data, alternatives to Landsat imagery need to be tested in an operational environment. In this study, normalized difference vegetation index (NDVI) values are derived from a Système Pour l'Observation de la Terre (SPOT), Moderate Resolution Imaging Spectroradiometer (MODIS), and Advanced Very High Resolution Radiometer (AVHRR) image and compared to the NDVI values from a Landsat image for LAI estimation in a semi-arid heterogeneous grassland. Results indicate a high agreement between Landsat and SPOT data with R2 over 85% at all buffer levels (100, 250, and 1000 m), and a significant but lower agreement between MODIS and Landsat with R2 around 28% at 250 m buffer level to 37% at 100 m buffer level. Based on in situ measurements of LAI in 22 homogeneous sites, the relationships established between LAI and NDVI show that SPOT and Landsat could predict LAI with acceptable accuracy, but MODIS and AVHRR cannot quantify the spatial variation in LAI measurements. Data fusion or blending techniques that combine the spectral information of high spatial/low temporal resolution data with low spatial/high temporal resolution data may be considered to study semi-arid heterogeneous grasslands.

  12. ANALISA KESEHATAN TANAMAN PADI BERDASARKAN NILAI NORMALIZED DIFFERENCE VEGETATION INDEX (NDVI MENGGUNAKAN CITRA ASTER (STUDI KASUS : KABUPATEN INDRAMAYU - JAWA BARAT

    Directory of Open Access Journals (Sweden)

    Prasetyo Rahaldi

    2015-02-01

    Full Text Available Padi merupakan salah satu tanaman budidaya yang terpenting karena merupakan makanan pokok bagi 90% penduduk Indonesia. Oleh sebab itu dibutuhkan analisa yang cepat dan akurat mengenai kesehatan tanaman padi. Dalam Penelitian ini NDVI atau Normalized Difference Vegetation Index merupakan metode yang digunakan dalam membandingkan tingkat kehijauan vegetasi yang berasal dari citra ASTER. Dari nilai NDVI tersebut dapat diketahui klasifikasi kesehatan tanaman padi. Dalam penelitian ini klasifikasi kesehatan tanaman padi dibagi menjadi  4 kelas. Kesehatan sangat baik terdapat pada rentang nilai NDVI 0.721-0.92, untuk kesehatan baik rentang nilai NDVI antara 0.421-0.72, dan nilai NDVI kesehatan normal terdapat pada rentang 0.221-0.42, sedangkan kesehatan buruk nilai NDVI 0.11-0.22. Selain itu juga menggunakan data Field Spectrometer sebanyak 14 titik sebagai data lapangan yang digunakan untuk proses validasi. Validasi ini mempunyai koefisien korelasi (R sebesar 0.829. Sehingga dapat dikatakan antara nilai hasil prediksi dan hasil pengukuran lapangan berkolerasi sebesar 82,9 %. Dengan data citra ASTER juga dihasilkan pustaka spektral dan peta kesehatan tanaman padi, dalam pustaka spektral semakin sehat tanaman nilai Digital Number pada band 2 semakin kecil. Sedangkan band 3 banyak dipantulkan atau tidak digunakan sehingga nilai Digital Number pada tanaman padi yang semakin sehat, nilainya semakin tinggi. Sedangkan dalam peta kesehatan tanaman padi klasifikasi kesehatan buruk luas areanya 3.949.560 Ha. Pada klasifikasi kesehatan normal luas areanya 14.877.315 Ha. Sedangkan pada klasifikasi kesehatan baik luas areanya 9.846.833 Ha dan pada klasifikasi kesehatan sangat baik luas areanya 8.922.892.

  13. Testing gridded land precipitation data and precipitation and runoff reanalyses (1982-2010) between 45° S and 45° N with Normalized Difference Vegetation Index data

    Science.gov (United States)

    Los, S. O.

    2014-12-01

    The realistic simulation of key components of the land-surface hydrological cycle - precipitation, runoff, evaporation and transpiration - in general circulation models of the atmosphere is crucial to assess adverse weather impacts on environment and society. Here, gridded precipitation data from observations and precipitation and runoff fields from reanalyses were tested with satellite-derived global vegetation index data for 1982-2010 and latitudes between 45° S and 45° N. Data were obtained from the Climate Research Unit (CRU), the Global Precipitation Climatology Project (GPCP) and Tropical Rainfall Monitoring Mission (TRMM; analysed for 1998-2010 only) and (precipitation and runoff) reanalyses were obtained from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR), the European Centre for Medium-Range Weather Forecasts (ECMWF) and the NASA Global Modelling and Assimilation Office (GMAO). Annual land-surface precipitation was converted to annual potential vegetation net primary productivity (NPP) and was compared to mean annual Normalized Difference Vegetation Index data measured by the Advanced Very High Resolution Radiometer (1982-1999) and MODIS (2001-2010). The effect of spatial resolution on the agreement between NPP and NDVI was investigated as well. The CRU and TRMM derived NPP agreed most closely with the NDVI data. The GPCP data showed weaker spatial agreement, largely because of their lower spatial resolution, but similar temporal agreement. MERRA Land and ERA Interim precipitation reanalyses showed similar spatial agreement as the GPCP data and good temporal agreement in semi-arid regions of the Americas, Asia, Australia and southern Africa. The NCEP/NCAR reanalysis showed the lowest spatial agreement which could only in part be explained by its lower spatial resolution. No reanalysis showed realistic interannual precipitation variations for northern tropical Africa. Inclusion of runoff in the NPP prediction resulted only in (marginally) better agreement for the MERRA Land reanalysis and worse agreement for the NCEP/NCAR and ERA Interim reanalyses.

  14. Testing gridded land precipitation data and precipitation and runoff reanalyses (1982-2010) between 45° S and 45° N with normalised difference vegetation index data

    Science.gov (United States)

    Los, S. O.

    2015-04-01

    The realistic simulation of key components of the land-surface hydrological cycle - precipitation, runoff, evaporation and transpiration, in general circulation models of the atmosphere - is crucial to assess adverse weather impacts on environment and society. Here, gridded precipitation data from observations and precipitation and runoff fields from reanalyses were tested with satellite derived global vegetation index data for 1982-2010 and latitudes between 45° S and 45° N. Data were obtained from the Climate Research Unit (CRU), the Global Precipitation Climatology Project (GPCP) and Tropical Rainfall Monitoring Mission (TRMM; analysed for 1998-2010 only) and precipitation and runoff reanalyses were obtained from the National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR), the European Centre for Medium-Range Weather Forecasts (ECMWF) and the NASA Global Modelling and Assimilation Office (GMAO). Annual land-surface precipitation was converted to annual potential vegetation net primary productivity (NPP) and was compared to mean annual normalised difference vegetation index (NDVI) data measured by the Advanced Very High Resolution Radiometer (AVHRR; 1982-1999) and Moderate Resolution Imaging Spectroradiometer (MODIS; 2001-2010). The effect of spatial resolution on the agreement between NPP and NDVI was investigated as well. The CRU and TRMM derived NPP agreed most closely with the NDVI data. The GPCP data showed weaker spatial agreement, largely because of their lower spatial resolution, but similar temporal agreement. MERRA Land and ERA Interim precipitation reanalyses showed similar spatial agreement to the GPCP data and good temporal agreement in semi-arid regions of the Americas, Asia, Australia and southern Africa. The NCEP/NCAR reanalysis showed the lowest spatial agreement, which could only in part be explained by its lower spatial resolution. No reanalysis showed realistic interannual precipitation variations for northern tropical Africa. Inclusion of runoff in the NPP prediction resulted only in marginally better agreement for the MERRA Land reanalysis and slightly worse agreement for the NCEP/NCAR and ERA Interim reanalyses.

  15. Evaluating and Quantifying the Climate-Driven Interannual Variability in Global Inventory Modeling and Mapping Studies (GIMMS) Normalized Difference Vegetation Index (NDVI3g) at Global Scales

    OpenAIRE

    Alvaro Ivanoff; G. James Collatz; Fan-Wei Zeng; Pinzon, Jorge E

    2013-01-01

    Satellite observations of surface reflected solar radiation contain information about variability in the absorption of solar radiation by vegetation. Understanding the causes of variability is important for models that use these data to drive land surface fluxes or for benchmarking prognostic vegetation models. Here we evaluated the interannual variability in the new 30.5-year long global satellite-derived surface reflectance index data, Global Inventory Modeling and Mapping Studies normalize...

  16. [Impact of moss soil crust on vegetation indexes interpretation].

    Science.gov (United States)

    Fang, Shi-bo; Zhang, Xin-shi

    2011-03-01

    Vegetation indexes were the most common and the most important parameters to characterizing large-scale terrestrial ecosystems. It is vital to get precise vegetation indexes for running land surface process models and computation of NPP change, moisture and heat fluxes over surface. Biological soil crusts (BSC) are widely distributed in arid and semi-arid, polar and sub-polar regions. The spectral characteristics of dry and wet BSCs were quite different, which could produce much higher vegetation indexes value for the wet BSC than for the dry BSC as reported. But no research was reported about whether the BSC would impact on regional vegetation indexes and how much dry and wet BSC had impact on regional vegetation indexes. In the present paper, the most common vegetation index NDVI were used to analyze how the moss soil crusts (MSC) dry and wet changes affect regional NDVI values. It was showed that 100% coverage of the wet MSC have a much higher NDVI value (0.657) than the dry MSC NDVI value (0.320), with increased 0.337. Dry and wet MSC NDVI value reached significant difference between the levels of 0.000. In the study area, MSC, which had the average coverage of 12.25%, would have a great contribution to the composition of vegetation index. Linear mixed model was employed to analyze how the NDVI would change in regional scale as wet MSC become dry MSC inversion. The impact of wet moss crust than the dry moss crust in the study area can make the regional NDVI increasing by 0.04 (14.3%). Due to the MSC existence and rainfall variation in arid and semi-arid zones, it was bound to result in NDVI change instability in a short time in the region. For the wet MSC's spectral reflectance curve is similar to those of the higher plants, misinterpretation of the vegetation dynamics could be more severe due to the "maximum value composite" (MVC) technique used to compose the global vegetation maps in the study of vegetation dynamics. The researches would be useful for detecting and mapping MSC from remote sensing imagery. It also is to the advantage to employing vegetation index wisely. PMID:21595239

  17. Spatial and temporal patterns of greenness on the Yamal Peninsula, Russia: interactions of ecological and social factors affecting the Arctic normalized difference vegetation index

    International Nuclear Information System (INIS)

    The causes of a greening trend detected in the Arctic using the normalized difference vegetation index (NDVI) are still poorly understood. Changes in NDVI are a result of multiple ecological and social factors that affect tundra net primary productivity. Here we use a 25 year time series of AVHRR-derived NDVI data (AVHRR: advanced very high resolution radiometer), climate analysis, a global geographic information database and ground-based studies to examine the spatial and temporal patterns of vegetation greenness on the Yamal Peninsula, Russia. We assess the effects of climate change, gas-field development, reindeer grazing and permafrost degradation. In contrast to the case for Arctic North America, there has not been a significant trend in summer temperature or NDVI, and much of the pattern of NDVI in this region is due to disturbances. There has been a 37% change in early-summer coastal sea-ice concentration, a 4% increase in summer land temperatures and a 7% change in the average time-integrated NDVI over the length of the satellite observations. Gas-field infrastructure is not currently extensive enough to affect regional NDVI patterns. The effect of reindeer is difficult to quantitatively assess because of the lack of control areas where reindeer are excluded. Many of the greenest landscapes on the Yamal are associated with landslides and drainage networks that have resulted from ongoing rapid permafrost degradation. A warming climate and enhanced winter snow are likely to exacerbate positive feedbacks between climate and permafrost thawing. We present a diagram that summarizes the social and ecological factors that influence Arctic NDVI. The NDVI should be viewed as a powerful monitoring tool that integrates the cumulative effect of a multitude of factors affecting Arctic land-cover change.

  18. Spatial and temporal patterns of greenness on the Yamal Peninsula, Russia: interactions of ecological and social factors affecting the Arctic normalized difference vegetation index

    Energy Technology Data Exchange (ETDEWEB)

    Walker, D A; Bhatt, U S; Raynolds, M K; Romanovsky, V E [University of Alaska Fairbanks, Fairbanks, AK (United States); Leibman, M O; Gubarkov, A A; Khomutov, A V; Moskalenko, N G; Orekhov, P; Ukraientseva, N G [Earth Cryosphere Institute, Russian Academy of Science, Siberian Branch, Tyumen (Russian Federation); Epstein, H E; Yu, Q [University of Virginia, Charlottesville, VA (United States); Forbes, B C; Kaarlejaervi, E [Arctic Center, University of Lapland, Rovaniemi (Finland); Comiso, J C [NASA Goddard Space Flight Center, MD (United States); Jia, G J [Chinese Academy of Sciences, Institute for Atmospheric Physics, Beijing (China); Kaplan, J O [Swiss Federal Institute for Forest Snow and Landscape Research, Birmensdorf (Switzerland); Kumpula, T [University of Joensuu, Joensuu (Finland); Kuss, P [University of Berne, Berne (Switzerland); Matyshak, G [Moscow State University, Moscow (Russian Federation)

    2009-10-15

    The causes of a greening trend detected in the Arctic using the normalized difference vegetation index (NDVI) are still poorly understood. Changes in NDVI are a result of multiple ecological and social factors that affect tundra net primary productivity. Here we use a 25 year time series of AVHRR-derived NDVI data (AVHRR: advanced very high resolution radiometer), climate analysis, a global geographic information database and ground-based studies to examine the spatial and temporal patterns of vegetation greenness on the Yamal Peninsula, Russia. We assess the effects of climate change, gas-field development, reindeer grazing and permafrost degradation. In contrast to the case for Arctic North America, there has not been a significant trend in summer temperature or NDVI, and much of the pattern of NDVI in this region is due to disturbances. There has been a 37% change in early-summer coastal sea-ice concentration, a 4% increase in summer land temperatures and a 7% change in the average time-integrated NDVI over the length of the satellite observations. Gas-field infrastructure is not currently extensive enough to affect regional NDVI patterns. The effect of reindeer is difficult to quantitatively assess because of the lack of control areas where reindeer are excluded. Many of the greenest landscapes on the Yamal are associated with landslides and drainage networks that have resulted from ongoing rapid permafrost degradation. A warming climate and enhanced winter snow are likely to exacerbate positive feedbacks between climate and permafrost thawing. We present a diagram that summarizes the social and ecological factors that influence Arctic NDVI. The NDVI should be viewed as a powerful monitoring tool that integrates the cumulative effect of a multitude of factors affecting Arctic land-cover change.

  19. Temporal Variation in Vegetation Indexes for Pine and Beech Stands During the Vegetation Season, Szczecin Lowland, Poland

    Directory of Open Access Journals (Sweden)

    Piekarski Pawe?

    2014-09-01

    Full Text Available Located in north-western Poland, the Bukowska Forest and Goleniowska Forest are vast woodlands consisting of areas with a homogeneous species composition that have been scarcely affected by humans. In this respect, they provided an excellent subject for scientific research, the purpose of which was to determine quantitative differences in selected vegetation indices of pine and beech stands in various periods during their vegetation seasons. Another purpose was to characterize the variation in these indices for each stand in its vegetation season. Four Landsat 5 TM images taken in 2007 and 2010 at four different points of vegetation season provided the basis for the analysis. In the analysis, 19 wooded areas with a homogeneous species composition were tested. In Bukowska Forest, the tested area was a beech stand, and in Goleniowska Forest, it was a pine stand. Acquired data was used to calculate the following vegetation indices: Normalized Difference Vegetation Index (NDVI, Transformed Vegetation Index (TVI, Green Normalized Difference Vegetation Index (Green NDVI, Normalized Difference Greenness Index (NDGI and Normalized Difference Index (NDI. Subsequent research allowed to establish that the beech and pine stands differed significantly with respect to their calculated vegetation indices. These differences derived both from the biochemical and structural attributes of leaves and needles, as well as from transformations that occur in the stands during vegetation seasons. Analysis of the indices’ allowed us to determine these differences and the influence of the stands’ phenological phases on the indices.

  20. Seasonal relationship between normalized difference vegetation index and abundance of the Phlebotomus kala-azar vector in an endemic focus in Bihar, India

    Directory of Open Access Journals (Sweden)

    Gouri S. Bhunia

    2012-11-01

    Full Text Available Remote sensing was applied for the collection of spatio-temporal data to increase our understanding of the potential distribution of the kala-azar vector Phlebotomus argentipes in endemic areas of the Vaishali district of Bihar, India. We produced monthly distribution maps of the normalized difference vegetation index (NDVI based on data from the thematic mapper (TM sensor onboard the Landsat-5 satellite. Minimum, maximum and mean NDVI values were computed for each month and compared with the concurrent incidence of kala-azar and the vector density. Maximum and mean NDVI values (R2 = 0.55 and R2 = 0.60, respectively, as well as the season likelihood ratio (X2 = 17.51; P <0.001, were found to be strongly associated with kala-azar, while the correlation with between minimum NDVI values and kala-azar was weak (R2 = 0.25. Additionally, a strong association was found between the mean and maximum NDVI values with seasonal vector abundance (R2 = 0.60 and R2 = 0.55, respectively but there was only a marginal association between minimum NDVI value and the spatial distribution of kala-azar vis-à-vis P. argentipes density.

  1. Reducing background effects in orchards through spectral vegetation index correction

    Science.gov (United States)

    Van Beek, Jonathan; Tits, Laurent; Somers, Ben; Deckers, Tom; Janssens, Pieter; Coppin, Pol

    2015-02-01

    Satellite remote sensing provides an alternative to time-consuming and labor intensive in situ measurements of biophysical variables in agricultural crops required for precision agriculture applications. In orchards, however, the spatial resolution causes mixtures of canopies and background (i.e. soil, grass and shadow), hampering the estimation of these biophysical variables. Furthermore, variable background mixtures obstruct meaningful comparisons between different orchard blocks, rows or within each row. Current correction methodologies use spectral differences between canopies and background, but struggle with a vegetated orchard floor. This background influence and the lack of a generic solution are addressed in this study. Firstly, the problem was demonstrated in a controlled environment for vegetation indices sensitive to chlorophyll content, water content and leaf area index. Afterwards, traditional background correction methods (i.e. soil-adjusted vegetation indices and signal unmixing) were compared to the proposed vegetation index correction. This correction was based on the mixing degree of each pixel (i.e. tree cover fraction) to rescale the vegetation indices accordingly and was applied to synthetic and WorldView-2 satellite imagery. Through the correction, the effect of background admixture for vegetation indices was reduced, and the estimation of biophysical variables was improved (?R2 = 0.2-0.31).

  2. A new burn severity index based on land surface temperature and enhanced vegetation index

    Science.gov (United States)

    Zheng, Zhong; Zeng, Yongnian; Li, Songnian; Huang, Wei

    2016-03-01

    Remotely sensed data have already become one of the major resources for estimating the burn severity of forest fires. Recently, Land Surface Temperature (LST) calculated from remote sensing data has been considered as a potential indicator for estimating burn severity. However, using the LST-based index alone may not be sufficient for estimating burn severity in the areas that has unburned trees and vegetation. In this paper, a new index is proposed by considering LST and enhanced vegetation index (EVI) together. The accuracy of the proposed index was evaluated by using 264 composite burn index (CBI) field sample data of the five fires across different regional eco-type areas in the Western United States. Results show that the proposed index performed equally well for post-fire areas covered with both sparse vegetation and dense vegetation and relatively better than some commonly-used burn severity indices. This index also has high potential of estimating burn severity if more accurate surface temperatures can be obtained in the future.

  3. Analysis of Urban Heat Island (UHI in Relation to Normalized Difference Vegetation Index (NDVI: A Comparative Study of Delhi and Mumbai

    Directory of Open Access Journals (Sweden)

    Aakriti Grover

    2015-04-01

    Full Text Available The formation and occurrence of urban heat island (UHI is a result of rapid urbanization and associated concretization. Due to intensification of heat combined with high pollution levels, urban areas expose humans to unexpected health risks. In this context, the study aims at comparing the UHI in the two largest metropolitan cities of India, i.e., Delhi and Mumbai. The presence of surface UHI is analyzed using the Landsat 5 TM image of 5 May 2010 for Delhi and the 17 April 2010 image for Mumbai. The validation of the heat island is done in relation to the Normalized Difference Vegetation Index (NDVI patterns. The study reveals that built-up and fallow lands record high temperatures, whereas the vegetated areas and water bodies exhibit lower temperatures. Delhi, an inland city, possesses mixed land use and the presence of substantial tree cover along roads; the Delhi Ridge forests and River Yamuna cutting across the city have a high influence in moderating the surface temperatures. The temperature reaches a maximum of 35 °C in West Delhi and a minimum of 24 °C in the east at the River Yamuna. Maximum temperature in East Delhi goes to 30 °C, except the border areas. North, Central and south Delhi have low temperatures (28 °C–31 °C, but the peripheral areas have high temperatures (36 °C–37 °C. The UHI is not very prominent in the case of Delhi. This is proven by the correlations of surface temperature with NDVI. South Delhi, New Delhi and areas close to River Yamuna have high NDVI and, therefore, record low temperatures. Mumbai, on the other hand, is a coastal city with lower tree cover than Delhi. The Borivilli National Park (BNP is in the midst of dense horizontal and vertical growth of buildings. The UHI is much stronger where the heat is trapped that is, the built-up zones. There are four small rivers in Mumbai, which have low carrying capacity. In Mumbai suburban district, the areas adjoining the creeks, sea and the lakes act as heat sinks. The coastal areas in South Mumbai record temperatures of 28 °C–31 °C; the Bandra-Kurla Complex has a high range of temperature i.e., 31 °C–36 °C. The temperature witnessed at Chattrapati Shivaji International Airport is as high as 38 °C. The temperature is nearly 37 °C–38 °C in the Dorai region in the Mumbai suburban district. The BNP has varied vegetation density, and therefore, the temperature ranges from 27 °C–31 °C. Powai Lake, Tulsi Lake and other water bodies record the lowest temperatures (24 °C–26 °C. There exists a strong negative correlation between NDVI and UHI of Mumbai, owing to less coverage of green and vegetation areas.

  4. Mapeamento do índice de vegetação da diferença normalizada em lavoura de algodão / Mapping of the normalized difference vegetation index in cotton field

    Scientific Electronic Library Online (English)

    Anamari Viegas de Araujo, Motomiya; José Paulo, Molin; Wagner Rogerio, Motomiya; Fábio Henrique, Rojo Baio.

    2012-03-01

    Full Text Available Os dados de sensoriamento remoto em campo podem fornecer informações detalhadas sobre a variabilidade de parâmetros biofísicos ligados à produtividade em grandes áreas e apresentam potencial para o monitoramento destes parâmetros, ao longo de todo o ciclo de desenvolvimento da cultura. Este trabalho [...] objetivou mapear a variabilidade espacial do índice de vegetação da diferença normalizada (NDVI) e seus componentes, em duas lavouras comerciais de algodão (Gossipium hirsutum L.), utilizando sensor óptico ativo, em nível terrestre. Os dados foram coletados utilizando-se sensor instalado em um pulverizador autopropelido agrícola. Um receptor GPS foi acoplado ao sensor, para a obtenção das coordenadas dos pontos de amostragem. As leituras foram realizadas em faixas espaçadas em 21,0 m, aproveitando-se as passadas do veículo no momento da pulverização de agroquímicos, e os dados submetidos à análise estatística clássica e geoestatística. Mapas de distribuição espacial das variáveis foram elaborados pela interpolação por krigagem. Observou-se maior variabilidade espacial do NDVI e da reflectância espectral da vegetação na região do infravermelho próximo (IVP) (880 nm) e do visível (590 nm) na lavoura com maior estresse fisiológico, devido ao ataque do percevejo castanho [Scaptocoris castanea (Hem.: Cydnidae)], em relação à lavoura sadia. Abstract in english The remote sensing data obtained at field level can provide detailed information about the variability of biophysical parameters related to yield over large areas, and present potential for monitoring these parameters throughout the crop development cycle. This study aimed to map the spatial variabi [...] lity of the Normalized Difference Vegetation Index (NDVI) and its components in two commercial cotton (Gossipium hirsutum L.) fields, by using an active optical sensor at the ground level. Data were collected with the aid of an optical sensor installed in a self-propelled agricultural sprayer. A GPS receiver was connected to the sensor, in order to obtain the coordinates of the sampling points. The readings were performed in rows spaced 21.0 m apart by the sensor installed on a vehicle, during the spraying operation, and data analyzed by using the classical statistics and geostatistics. Spatial distribution maps of the variables were generated by kriging interpolation. It was observed a higher spatial variability of NDVI and spectral reflectance of vegetation in the region of near infrared (NIR) (880 nm) and visible infrared (590 nm) in the crop with higher physiological stress, due to the brown bug [Scaptocoris castanea (Hem.: Cydnidae)] attack, when compared to the healthy one.

  5. [Soil moisture estimation model based on multiple vegetation index].

    Science.gov (United States)

    Wu, Hai-long; Yu, Xin-xiao; Zhang, Zhen-ming; Zhang, Yan

    2014-06-01

    Estimating soil moisture conveniently and exactly is a hot issues in water resource monitoring among agriculture and forestry. Estimating soil moisture based on vegetation index has been recognized and applied widely. 8 vegetation indexes were figured out based on the hyper-spectral data measured by portable spectrometer. The higher correlation indexes among 8 vegetation indexes and surface vegetation temperature were selected by Gray Relative Analysis method (GRA). Then, these selected indexes were analyzed using Multiple Linear Regression to establish soil moisture estimation model based on multiple vegetation indexes, and the model accuracy was evaluated. The accuracy evaluation indicated that the fitting was satisfied and the significance was 0.000 (P remote sensing inversion and direct measurement. The model could estimate soil moisture quickly and accurately, and provide theory and technology reference for water resource management in agriculture and forestry. PMID:25358174

  6. Investigation on the Patterns of Global Vegetation Change Using a Satellite-Sensed Vegetation Index

    Directory of Open Access Journals (Sweden)

    Ainong Li

    2010-06-01

    Full Text Available The pattern of vegetation change in response to global change still remains a controversial issue. A Normalized Difference Vegetation Index (NDVI dataset compiled by the Global Inventory Modeling and Mapping Studies (GIMMS was used for analysis. For the period 1982–2006, GIMMS-NDVI analysis indicated that monthly NDVI changes show homogenous trends in middle and high latitude areas in the northern hemisphere and within, or near, the Tropic of Cancer and Capricorn; with obvious spatio-temporal heterogeneity on a global scale over the past two decades. The former areas featured increasing vegetation activity during growth seasons, and the latter areas experienced an even greater amplitude in places where precipitation is adequate. The discussion suggests that one should be cautious of using the NDVI time-series to analyze local vegetation dynamics because of its coarse resolution and uncertainties.

  7. Phenology-Based Vegetation Index Differencing for Mapping of Rubber Plantations Using Landsat OLI Data

    Directory of Open Access Journals (Sweden)

    Hui Fan

    2015-05-01

    Full Text Available Accurate and up-to-date mapping and monitoring of rubber plantations is challenging. In this study, we presented a simple method for rapidly and accurately mapping rubber plantations in the Xishuangbanna region of southwest China using phenology-based vegetation index differencing. Temporal profiles of the Normalized Difference Vegetation Index (NDVI, Enhanced Vegetation Index (EVI, Atmospherically Resistant Vegetation Index (ARVI, Normalized Difference Moisture Index (NDMI, and Tasselled Cap Greenness (TCG for rubber trees, natural forests and croplands were constructed using 11 Landsat 8 OLI images acquired within one year. These vegetation index time series accurately demonstrated the unique seasonal phenological dynamics of rubber trees. Two distinct phenological phases (i.e., defoliation and foliation of rubber trees were clearly distinguishable from natural forests and croplands. Rubber trees undergo a brief defoliation-foliation process between late December and mid-March. Therefore, vegetation index differencing between the nearly complete defoliation (leaf-off and full foliation (leaf flushing phases was used to delineate rubber plantations within fragmented tropical mountainous landscapes. The method presented herein greatly improved rubber plantation classification accuracy. Overall classification accuracies derived from the differences of the five vegetation indices varied from 92% to 96% with corresponding kappa coefficients of 0.84–0.92. These results demonstrate the promising potential of phenology-based vegetation index differencing for mapping and monitoring rubber expansion at the regional scale.

  8. Estimating Crop Coefficients Using Remote Sensing-Based Vegetation Index

    Directory of Open Access Journals (Sweden)

    Kenneth Hubbard

    2013-03-01

    Full Text Available Crop coefficient (Kc-based estimation of crop evapotranspiration is one of the most commonly used methods for irrigation water management. However, uncertainties of the generalized dual crop coefficient (Kc method of the Food and Agricultural Organization of the United Nations Irrigation and Drainage Paper No. 56 can contribute to crop evapotranspiration estimates that are substantially different from actual crop evapotranspiration. Similarities between the crop coefficient curve and a satellite-derived vegetation index showed potential for modeling a crop coefficient as a function of the vegetation index. Therefore, the possibility of directly estimating the crop coefficient from satellite reflectance of a crop was investigated. The Kc data used in developing the relationship with NDVI were derived from back-calculations of the FAO-56 dual crop coefficients procedure using field data obtained during 2007 from representative US cropping systems in the High Plains from AmeriFlux sites. A simple linear regression model ( is developed to establish a general relationship between a normalized difference vegetation index (NDVI from a moderate resolution satellite data (MODIS and the crop coefficient (Kc calculated from the flux data measured for different crops and cropping practices using AmeriFlux towers. There was a strong linear correlation between the NDVI-estimated Kc and the measured Kc with an r2 of 0.91 and 0.90, while the root-mean-square error (RMSE for Kc in 2006 and 2007 were 0.16 and 0.19, respectively. The procedure for quantifying crop coefficients from NDVI data presented in this paper should be useful in other regions of the globe to understand regional irrigation water consumption.

  9. Sub-Pixel Reflectance Unmixing in Estimating Vegetation Water Content and Dry Biomass of Corn and Soybeans Cropland using Normalized Difference Water Index (NDWI) from Satellites

    Science.gov (United States)

    Estimating vegetation cover, water content and dry biomass from space plays a significant role in a variety of scientific fields including drought monitoring, climate modeling, and agricultural prediction. However, getting accurate and consistent measurements of vegetation is complicated very often ...

  10. A MODIS-based vegetation index climatology

    Science.gov (United States)

    Our motivation here is to provide information for the NASA Soil Moisture Active Passive (SMAP) satellite soil moisture retrieval algorithms (launch in 2014). Vegetation attenuates the signal and the algorithms must correct for this effect. One approach is to use data that describes the canopy water ...

  11. Investigation of soil influences in AVHRR red and near-infrared vegetation index imagery

    Science.gov (United States)

    Huete, A. R.; Tucker, C. J.

    1991-01-01

    The effects of soil optical properties on vegetation index imagery are analyzed with ground-based spectral measurements and both simulated and actual AVHRR data from the NOAA satellites. Soil effects on vegetation indices were divided into primary variations associated with the brightness of bare soils, secondary variations attributed to 'color' differences among bare soils, and soil-vegetation spectral mixing. Primary variations were attributed to shifts in the soil line owing to atmosphere or soil composition. Secondary soil variance was responsible for the Saharan desert 'artefact' areas of increased vegetation index response in AVHRR imagery.

  12. The use of a satellite derived vegetation index for assessment of the urban heat island effect

    Science.gov (United States)

    Gallo, Kevin P.; Tarpley, J. D.; Mcnab, Alan L.; Karl, Thomas R.; Brown, Jesslyn F.

    1993-01-01

    Satellite derived normalized difference (ND) vegetation index data, based on urban and rural region composed of a variety of land surface environments, are evaluated. These data are linearly related to the difference in observed urban and rural minimum temperatures. It is concluded that the difference in the ND index between urban and rural regions reflects the difference in the surface properties (evaporation and heat storage capacity) of these two environments and urban and rural minimum temperatures (the urban heat island effect).

  13. A PROPOSED NEW VEGETATION INDEX, THE TOTAL RATIO VEGETATION INDEX (TRVI, FOR ARID AND SEMI-ARID REGIONS

    Directory of Open Access Journals (Sweden)

    H. Fadaei

    2012-07-01

    Full Text Available Vegetation indices that provide important key to predict amount vegetation in forest such as percentage vegetation cover, aboveground biomass, and leaf-area index. Arid and semi-arid areas are not exempt of this rule. Arid and semi-arid areas of northeast Iran cover about 3.4 million ha and are populated by two main tree species, the broadleaf Pistacia vera (pistachio and the conifer Juniperus excelsa ssp. polycarpos (Persian juniper. Natural stands of pistachio in Iran are not only environmentally important but also genetically essential as seed sources for pistachio production in orchards. We investigated the relationships between tree density and vegetation indices in the arid and semi-arid regions in the northeast of Iran by analysing Advanced Land Observing Satellite (ALOS data PRISM is a panchromatic radiometer with a 2.5 m spatial resolution at nadir, and has one band with a wavelength of 0.52–0.77 ?m (JAXA EORC. AVNIR-2 is a visible and near infrared radiometer for observing land and coastal zones with a 10 m spatial resolution at nadir, and has four multispectral bands: blue (0.42–0.50 ?m, green (0.52–0.60 ?m, red (0.61–0.69 ?m, and near infrared (0.76–0.89 ?m (JAXA EORC. In this study, we estimated various vegetation indices using maximum filtering algorithm (5×5 and examined. This study carried out of juniper forests and natural pistachio stand using Advanced Land Observing Satellite (ALOS and field inventories. Have been compared linear regression model of vegetation indices and proposed new vegetation index for arid and semi-arid regions. Also, we estimated the densities of juniper forests and natural pistachio stands using remote sensing to help in the sustainable management and production of pistachio in Iran. We present a new vegetation index for arid and semi-arid regions with sparse forest cover, the Total Ratio Vegetation Index (TRVI, and we investigate the relationship of the new index to tree density by analysing data from the Advanced Land Observing Satellite (ALOS using 5×5 maximum filtering algorithms. The results for pistachio forest showed the coefficient regression of NDVI, SAVI, MSAVI, OSAVI, and TRVI were (R2= 0.68, 0.67, 0.68, 0.68, and 0.71 respectively. The results for juniper forest showed the coefficient regression of NDVI, SAVI, MSAVI, OSAVI, and TRVI were (R2= 0.51, 0.52, 0.51, 0.52, and 0.56 respectively. I hope this research can provide decision of managers to helping sustainable management for arid and semi-arid regions in Iran.

  14. a Proposed New Vegetation Index, the Total Ratio Vegetation Index (trvi), for Arid and Semi-Arid Regions

    Science.gov (United States)

    Fadaei, H.; Suzuki, R.; Sakai, T.; Torii, K.

    2012-07-01

    Vegetation indices that provide important key to predict amount vegetation in forest such as percentage vegetation cover, aboveground biomass, and leaf-area index. Arid and semi-arid areas are not exempt of this rule. Arid and semi-arid areas of northeast Iran cover about 3.4 million ha and are populated by two main tree species, the broadleaf Pistacia vera (pistachio) and the conifer Juniperus excelsa ssp. polycarpos (Persian juniper). Natural stands of pistachio in Iran are not only environmentally important but also genetically essential as seed sources for pistachio production in orchards. We investigated the relationships between tree density and vegetation indices in the arid and semi-arid regions in the northeast of Iran by analysing Advanced Land Observing Satellite (ALOS) data PRISM is a panchromatic radiometer with a 2.5 m spatial resolution at nadir, and has one band with a wavelength of 0.52-0.77 ?m (JAXA EORC). AVNIR-2 is a visible and near infrared radiometer for observing land and coastal zones with a 10 m spatial resolution at nadir, and has four multispectral bands: blue (0.42-0.50 ?m), green (0.52-0.60 ?m), red (0.61-0.69 ?m), and near infrared (0.76-0.89 ?m) (JAXA EORC). In this study, we estimated various vegetation indices using maximum filtering algorithm (5×5) and examined. This study carried out of juniper forests and natural pistachio stand using Advanced Land Observing Satellite (ALOS) and field inventories. Have been compared linear regression model of vegetation indices and proposed new vegetation index for arid and semi-arid regions. Also, we estimated the densities of juniper forests and natural pistachio stands using remote sensing to help in the sustainable management and production of pistachio in Iran. We present a new vegetation index for arid and semi-arid regions with sparse forest cover, the Total Ratio Vegetation Index (TRVI), and we investigate the relationship of the new index to tree density by analysing data from the Advanced Land Observing Satellite (ALOS) using 5×5 maximum filtering algorithms. The results for pistachio forest showed the coefficient regression of NDVI, SAVI, MSAVI, OSAVI, and TRVI were (R2= 0.68, 0.67, 0.68, 0.68, and 0.71) respectively. The results for juniper forest showed the coefficient regression of NDVI, SAVI, MSAVI, OSAVI, and TRVI were (R2= 0.51, 0.52, 0.51, 0.52, and 0.56) respectively. I hope this research can provide decision of managers to helping sustainable management for arid and semi-arid regions in Iran.

  15. Radiative transfer in shrub savanna sites in Niger: Preliminary results from HAPEX-Sahel. Part 3: Optical dynamics and vegetation index sensitivity to biomass and plant cover

    Science.gov (United States)

    vanLeeuwen, W. J. D.; Huete, A. R.; Duncan, J.; Franklin, J.

    1994-01-01

    A shrub savannah landscape in Niger was optically characterized utilizing blue, green, red and near-infrared wavelengths. Selected vegetation indices were evaluated for their performance and sensitivity to describe the complex Sahelian soil/vegetation canopies. Bidirectional reflectance factors (BRF) of plants and soils were measured at several view angles, and used as input to various vegetation indices. Both soil and vegetation targets had strong anisotropic reflectance properties, rendering all vegetation index (6) responses to be a direct function of sun and view geometry. Soil background influences were shown to alter the response of most vegetation indices. N-space greenness had the smallest dynamic range in VI response, but the n-space brightness index provided additional useful information. The global environmental monitoring index (GEMI) showed a large 6 dynamic range for bare soils, which was undesirable for a vegetation index. The view angle response of the normalized difference vegetation index (NDVI), atmosphere resistant vegetation index (ARVI) and soil atmosphere resistant vegetation index (SARVI) were asymmetric about nadir for multiple view angles, and were, except for the SARVI, altered seriously by soil moisture and/or soil brightness effects. The soil adjusted vegetation index (SAVI) was least affected by surface soil moisture and was symmetric about nadir for grass vegetation covers. Overall the SAVI, SARVI and the n-space vegetation index performed best under all adverse conditions and were recommended to monitor vegetation growth in the sparsely vegetated Sahelian zone.

  16. Radiative transfer in shrub savanna sites in Niger: preliminary results from HAPEX-Sahel. 3. Optical dynamics and vegetation index sensitivity to biomass and plant cover

    International Nuclear Information System (INIS)

    A shrub savannah landscape in Niger was optically characterized utilizing blue, green, red and near-infrared wavelengths. Selected vegetation indices were evaluated for their performance and sensitivity to describe the complex Sahelian soil/vegetation canopies. Bidirectional reflectance factors (BRF) of plants and soils were measured at several view angles, and used as input to various vegetation indices. Both soil and vegetation targets had strong anisotropic reflectance properties, rendering all vegetation index (VI) responses to be a direct function of sun and view geometry. Soil background influences were shown to alter the response of most vegetation indices. N-space greenness had the smallest dynamic range in VI response, but the n-space brightness index provided additional useful information. The global environmental monitoring index (GEMI) showed a large VI dynamic range for bare soils, which was undesirable for a vegetation index. The view angle response of the normalized difference vegetation index (NDVI), atmosphere resistant vegetation index (ARVI) and soil atmosphere resistant vegetation index (SARVI) were asymmetric about nadir for multiple view angles, and were, except for the SARVI, altered seriously by soil moisture and/or soil brightness effects. The soil adjusted vegetation index (SAVI) was least affected by surface soil moisture and was symmetric about nadir for grass vegetation covers. Overall the SAVI, SARVI and the n-space vegetation index performed best under all adverse conditions and were recommended to monitor vegetation growth in the sparsely vegetated Sahelian zone. (author)

  17. Statistical analysis of land surface temperature-vegetation indexes relationship through thermal remote sensing.

    Science.gov (United States)

    Kumar, Deepak; Shekhar, Sulochana

    2015-11-01

    Vegetation coverage has a significant influence on the land surface temperature (LST) distribution. In the field of urban heat islands (UHIs) based on remote sensing, vegetation indexes are widely used to estimate the LST-vegetation relationship. This paper devises two objectives. The first analyzes the correlation between vegetation parameters/indicators and LST. The subsequent computes the occurrence of vegetation parameter, which defines the distribution of LST (for quantitative analysis of urban heat island) in Kalaburagi (formerly Gulbarga) City. However, estimation work has been done on the valuation of the relationship between different vegetation indexes and LST. In addition to the correlation between LST and the normalized difference vegetation index (NDVI), the normalized difference build-up index (NDBI) is attempted to explore the impacts of the green land to the build-up land on the urban heat island by calculating the evaluation index of sub-urban areas. The results indicated that the effect of urban heat island in Kalaburagi city is mainly located in the sub-urban areas or Rurban area especially in the South-Eastern and North-Western part of the city. The correlation between LST and NDVI, indicates the negative correlation. The NDVI suggests that the green land can weaken the effect on urban heat island, while we perceived the positive correlation between LST and NDBI, which infers that the built-up land can strengthen the effect of urban heat island in our case study. Although satellite data (e.g., Landsat TM thermal bands data) has been applied to test the distribution of urban heat islands, but the method still needs to be refined with in situ measurements of LST in future studies. PMID:26209299

  18. On the terminology of the spectral vegetation index (NIR – SWIR)/(NIR + SWIR)

    Science.gov (United States)

    Ji, Lel; Zhang, Li; Wylie, Bruce K.; Rover, Jennifer

    2011-01-01

    The spectral vegetation index (?NIR – ?SWIR)/(?NIR + ?SWIR), where ?NIR and ?SWIR are the near-infrared (NIR) and shortwave-infrared (SWIR) reflectances, respectively, has been widely used to indicate vegetation moisture condition. This index has multiple names in the literature, including infrared index (II), normalized difference infrared index (NDII), normalized difference water index (NDWI), normalized difference moisture index (NDMI), land surface water index (LSWI), and normalized burn ratio (NBR), etc. After reviewing each term’s definition, associated sensors, and channel specifications, we found that the index consists of three variants, differing only in the SWIR region (1.2–1.3 µm, 1.55–1.75 µm, or 2.05–2.45 µm). Thus, three terms are sufficient to represent these three SWIR variants; other names are redundant and therefore unnecessary. Considering the spectral representativeness, the term’s popularity, and the “rule of priority” in scientific nomenclature, NDWI, NDII, and NBR, each corresponding to the three SWIR regions, are more preferable terms.

  19. EROS MODIS Normalized Difference Vegetation Index

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — eMODIS processes calibrated radiance data (level-1B) acquired by the MODIS sensors on the EOS Terra and Aqua satellites by combining MODIS Land Science Collection 5...

  20. The use of a vegetation index for assessment of the urban heat island effect

    Science.gov (United States)

    Gallo, K. P.; Mcnab, A. L.; Karl, T. R.; Brown, J. F.; Hood, J. J.; Tarpley, J. D.

    1993-01-01

    A vegetation index and radiative surface temperature were derived from NOAA-11 Advanced Very High Resolution Radiometer (AVHRR) data for the Seattle, WA region from 28 June through 4 July 1991. The vegetation index and surface temperature values were computed for locations of weather observation stations within the region and compared to observed minimum air temperatures. These comparisons were used to evaluate the use of AVHRR data to assess the influence of the urban environment on observed minimum air temperatures (the urban heat island effect). AVHRR derived normalized difference vegetation index (NDVI) and radiant surface temperature data from a one week composite product were both related significantly to observed minimum temperatures, however, the vegetation index accounted for a greater amount of the spatial variation observed in mean minimum temperatures. The difference in the NDVI between urban and rural regions appears to be an indicator of the difference in surface properties (i.e., evaporation and heat storage capacity) between the two environments that are responsible for differences in urban and rural minimum temperatures.

  1. Vegetation

    DEFF Research Database (Denmark)

    Epstein, H.E.; Walker, D.A.; Bhatt, U.S.; Bieniek, P.; Comiso, J.; Pinzon, J.; Raynolds, M.K.; Tucker, C.J.; Jia, G.J.; Zeng, H.; Myers-Smith, I.H.; Forbes, B.C.; Blok, Daan; Loranty, M.M.; Beck, P.S.A.; Goetz, S.J.; Callaghan, T.V.; Henry, G.H.R.; Tweedie, C.E.; Webber, P.J.; Rocha, A.V.; Shaver, G.R.; Welker, J.M.

    • Over the past 30 years (1982-2011), the Normalized Difference Vegetation Index (NDVI), an index of green vegetation, has increased 15.5% in the North American Arctic and 8.2% in the Eurasian Arctic. In the more southern regions of Arctic tundra, the estimated aboveground plant biomass has...... increased 20-26%. • Increasing shrub growth and range extension throughout the Low Arctic are related to winter and early growing season temperature increases. Growth of other tundra plant types, including graminoids and forbs, is increasing, while growth of mosses and lichens is decreasing. • Increases in...... vegetation (including shrub tundra expansion) and thunderstorm activity, each a result of Arctic warming, have created conditions that favor a more active Arctic fire regime....

  2. Vegetation

    DEFF Research Database (Denmark)

    Epstein, H.E.; Walker, D.A.

    2012-01-01

    • Over the past 30 years (1982-2011), the Normalized Difference Vegetation Index (NDVI), an index of green vegetation, has increased 15.5% in the North American Arctic and 8.2% in the Eurasian Arctic. In the more southern regions of Arctic tundra, the estimated aboveground plant biomass has increased 20-26%. • Increasing shrub growth and range extension throughout the Low Arctic are related to winter and early growing season temperature increases. Growth of other tundra plant types, including graminoids and forbs, is increasing, while growth of mosses and lichens is decreasing. • Increases in vegetation (including shrub tundra expansion) and thunderstorm activity, each a result of Arctic warming, have created conditions that favor a more active Arctic fire regime.

  3. Validating a Dynamic Global Vegetation Model with Remotely Sensed Vegetation Index

    Directory of Open Access Journals (Sweden)

    Jiaxin Jin

    2013-02-01

    Full Text Available The present study aims to evaluate the ability of IBIS model to capture the difference in vegetation characteristics among six major biomes in the Northeast China Transect and to calibrate the simulated LAI by IBIS, using the product of MODIS LAI (Leaf Area Index. The results showed that IBIS simulated a little lower growing season LAI over temperate evergreen conifer forest and boreal evergreen forest, while it overestimated LAI relative to MODIS in non-growing season. IBIS performed poorly on LAI over savanna, grassland and shrub land, compared with MODIS and it nearly simulated higher LAI throughout the year. Based on regression analysis, the simulating LAI by IBIS (Integrated Biosphere Simulator presented a significant linear correlation with that from MODIS over temperate evergreen conifer forest in spring and winter, boreal evergreen forest throughout the year and grassland from summer to early autumn. Therefore, it was help to adjust the model parameters over these plant functional types to calibrate the estimated LAI in a large spatial scale.

  4. Disturbance metrics predict a wetland Vegetation Index of Biotic Integrity

    Science.gov (United States)

    Stapanian, Martin A.; Mack, John; Adams, Jean V.; Gara, Brian; Micacchion, Mick

    2013-01-01

    Indices of biological integrity of wetlands based on vascular plants (VIBIs) have been developed in many areas in the USA. Knowledge of the best predictors of VIBIs would enable management agencies to make better decisions regarding mitigation site selection and performance monitoring criteria. We use a novel statistical technique to develop predictive models for an established index of wetland vegetation integrity (Ohio VIBI), using as independent variables 20 indices and metrics of habitat quality, wetland disturbance, and buffer area land use from 149 wetlands in Ohio, USA. For emergent and forest wetlands, predictive models explained 61% and 54% of the variability, respectively, in Ohio VIBI scores. In both cases the most important predictor of Ohio VIBI score was a metric that assessed habitat alteration and development in the wetland. Of secondary importance as a predictor was a metric that assessed microtopography, interspersion, and quality of vegetation communities in the wetland. Metrics and indices assessing disturbance and land use of the buffer area were generally poor predictors of Ohio VIBI scores. Our results suggest that vegetation integrity of emergent and forest wetlands could be most directly enhanced by minimizing substrate and habitat disturbance within the wetland. Such efforts could include reducing or eliminating any practices that disturb the soil profile, such as nutrient enrichment from adjacent farm land, mowing, grazing, or cutting or removing woody plants.

  5. Mapping potato crop height and leaf area index through vegetation indices using remote sensing in Cyprus

    Science.gov (United States)

    Papadavid, George; Hadjimitsis, Diofantos; Toulios, Leonidas; Michaelides, Silas

    2011-01-01

    This paper aims to model leaf area index (LAI) and crop height to spectral vegetation indices (VI), such as normalized difference vegetation index (NDVI) and soil adjusted vegetation index (SAVI), and weighted difference vegetation index (WDVI). The intended purpose is to create empirical statistical models to support evapotranspiration algorithms applied under the current conditions in the island of Cyprus. Indeed, a traditionally agricultural area was selected in the Mandria Village in the Paphos District area in Cyprus, where one of the island's main exported crops, potatoes, are cultivated. A GER-1500 field spectroradiometer was used in this study in order to retrieve the necessary spectrum data of the different crops for estimating the VI's. A field campaign was undertaken with spectral measurements of LAI and crop height using the Sun-Scan canopy analyzer, acquired simultaneously with the spectroradiometric measurements between March and April of 2008 and 2009. Regarding the measurements, the phenological cycle of potatoes was followed. Several regression models have been applied to relate LAI/crop height and the three indices. It was found that the best fitted vegetation index to both LAI and crop height was WDVI. When LAI was regressed against WDVI for potatoes, the determination coefficient (R2) was 0.72, while for crop height R2 reached 0.78. Two Landsat TM-5 images acquired simultaneously during the spectroradiometric and LAI and crop height measurements are used to validate the proposed regression model. From the whole analysis it was found that the modeled results are very close to real values. This fact enables the specific empirical models to be used in the future for hydrological purposes.

  6. Assessment of regional biomass-soil relationships using vegetation indexes

    Science.gov (United States)

    Lozano-Garcia, D. Fabian; Fernandez, R. Norberto; Johannsen, Chris J.

    1991-01-01

    The development of photosynthetic active biomass in different ecological conditions, as indicated by normalized difference vegetation indices (NDVIs) is compared by performing a stratified sampling (based on soil assocations) on data acquired over Indiana. Data from the NOAA-10 AVHRR were collected for the 1987 and 1988 growing seasons. An NDVI transformation was performed using the two optical bands of the sensor (0.58-0.68 microns and 0.72-1.10 microns). The NDVI is related to the amount of active photosynthetic biomass present on the ground. Samples of NDVI values over 45 fields representing eight soil associations throughout Indiana were collected to assess the effect of soil conditions and acquisition date on the spectral response of the vegetation, as shown by the NDVIs. Statistical analysis of results indicate that land-cover types (forest, forest/pasture, and crops), soil texture, and soil water-holding capacity have an important effect on vegetation biomass changes as measured by AVHRR data. Acquisition dates should be selected with condideration of the phenological stages of vegetation. Sampling of AVHRR data over extended areas should be stratified according to physiographic units rather than man-made boundaries. This will provide more homogeneous samples for statistical analysis.

  7. The Application of Modified Normalized Difference Water Index (MNDWI) by Leaf Area Index in the Retrieval of Regional Drought Monitoring

    OpenAIRE

    H.-w. Zhang; H.-l. Chen

    2015-01-01

    The vegetation coverage is one of the important factors that restrict the accuracy of remote sensing retrieval of soil moisture. In order to effectively improve the accuracy of the remote sensing retrieval of soil moisture and to reduce the impact of vegetation coverage variation on the retrieval accuracy, the Leaf Area Index (LAI) is introduced to the Normalized Difference Water Index (NDWI) to greatly improve the accuracy of the soil moisture retrieval. In its application on the re...

  8. [Research on Accuracy and Stability of Inversing Vegetation Chlorophyll Content by Spectral Index Method].

    Science.gov (United States)

    Jiang, Hai-ling; Yang, Hang; Chen, Xiao-ping; Wang, Shu-dong; Li, Xue-ke; Liu, Kai; Cen, Yi

    2015-04-01

    Spectral index method was widely applied to the inversion of crop chlorophyll content. In the present study, PSR3500 spectrometer and SPAD-502 chlorophyll fluorometer were used to acquire the spectrum and relative chlorophyll content (SPAD value) of winter wheat leaves on May 2nd 2013 when it was at the jointing stage of winter wheat. Then the measured spectra were resampled to simulate TM multispectral data and Hyperion hyperspectral data respectively, using the Gaussian spectral response function. We chose four typical spectral indices including normalized difference vegetation index (NDVD, triangle vegetation index (TVI), the ratio of modified transformed chlorophyll absorption ratio index (MCARI) to optimized soil adjusted vegetation index (OSAVI) (MCARI/OSAVI) and vegetation index based on universal pattern decomposition (VIUPD), which were constructed with the feature bands sensitive to the vegetation chlorophyll. After calculating these spectral indices based on the resampling TM and Hyperion data, the regression equation between spectral indices and chlorophyll content was established. For TM, the result indicates that VIUPD has the best correlation with chlorophyll (R2 = 0.819 7) followed by NDVI (R2 = 0.791 8), while MCARI/OSAVI and TVI also show a good correlation with R2 higher than 0.5. For the simulated Hyperion data, VIUPD again ranks first with R2 = 0.817 1, followed by MCARI/OSAVI (R2 = 0.658 6), while NDVI and TVI show very low values with R2 less than 0.2. It was demonstrated that VIUPD has the best accuracy and stability to estimate chlorophyll of winter wheat whether using simulated TM data or Hyperion data, which reaffirms that VIUPD is comparatively sensor independent. The chlorophyll estimation accuracy and stability of MCARI/OSAVI also works well, partly because OSAVI could reduce the influence of backgrounds. Two broadband spectral indices NDVI and TVI are weak for the chlorophyll estimation of simulated Hyperion data mainly because of their dependence on few bands and the strong influence of atmosphere, solar altitude, viewing angle of sensor, background and so on. In conclusion, the stability and consistency of chlorophyll estimation is equally important to the estimation accuracy by spectral index method. VIUPD introduced in the study has the best performance to estimate winter wheat chlorophyll, which illustrates its potential ability in the area of estimating vegetation biochemical parameters. PMID:26197586

  9. Heterogeneity as an index of anthropogenic disturbance of soil and vegetation in urban Parks

    Science.gov (United States)

    Zhevelev, H.; Sarah, P.

    2012-04-01

    The conditions of urban ecosystems depend on a wide range of anthropogenic factors, one of which is visitor pressure on urban parks. This study aims: (1) to analyze soil properties and vegetation characteristics of different open areas, and (2) to determine an index of disturbance for these areas, according to their spatial heterogeneity. The study was conducted in Tel-Aviv, and addressed two scales: (1) Land Use Units (municipal parks and vacant lots); and (2) Microenvironment (under tree, under bush, herbaceous area, lawn, and path). In each type of microenvironment, soil was sampled at seven points, from layers at two depths (0-2 and 5-10 cm). Before the sampling, penetration depth, litter biomass and vegetation characteristics (vegetation cover, number of species, and vegetation height) were determined in the field. In each soil sample gravimetric soil moisture and organic matter contents were determined, and pH, electrical conductivity and soluble-ion contents were measured in a 1:1 water extraction. The level of disturbance by visitors was scored for each microenvironment according to field evidence of trampling, such as lack of vegetation cover and litter biomass. The results show strong differences in soil properties among the various microenvironments: penetration depth ranged from a few millimeters up to ~ 3 cm; organic matter content from less than 1% to 10%; soil moisture content from a few percents to ~ 30%; electrical conductivity from ~ 0.3 to ~2 dS/m; sodium content from ~ 1 to 7.5 meq/kg; chlorine content from ~ 0.5 to ~9 meq/kg; and litter biomass from 0.5 to 1.4 kg/m2. The vegetation characteristics also varied among the microenvironments: vegetation cover ranged from 11 to 99 %; number of species from 2 to11; and vegetation height from 5 to 35 cm. In order to assess the level of heterogeneity of soil and vegetation, an integral index, based on the number of Duncan groups, has been calculated. Regarding the Scale of Land Use unit, it was found that the highest heterogeneity of soil characteristics corresponded with the lowest species richness. For the smaller-scale unit - Microenvironment - an index was developed that defines the status of disturbance, and it was used to sort the microenvironments into several groups. High correlation between percentiles and averages of soil properties was found for the microenvironments. This hints at a fractal structure of soil properties distribution at the microenvironment level.

  10. Analysis of agricultural drought using vegetation temperature condition index (VTCI) from Terra/MODIS satellite data.

    Science.gov (United States)

    Patel, N R; Parida, B R; Venus, V; Saha, S K; Dadhwal, V K

    2012-12-01

    The most commonly used normalized difference vegetation index (NDVI) from remote sensing often fall short in real-time drought monitoring due to a lagged vegetation response to drought. Therefore, research recently emphasized on the use of combination of surface temperature and NDVI which provides vegetation and moisture conditions simultaneously. Since drought stress effects on agriculture are closely linked to actual evapotranspiration, we used a vegetation temperature condition index (VTCI) which is more closely related to crop water status and holds a key place in real-time drought monitoring and assessment. In this study, NDVI and land surface temperature (T (s)) from MODIS 8-day composite data during cloud-free period (September-October) were adopted to construct an NDVI-T (s) space, from which the VTCI was computed. The crop moisture index (based on estimates of potential evapotranspiration and soil moisture depletion) was calculated to represent soil moisture stress on weekly basis for 20 weather monitoring stations. Correlation and regression analysis were attempted to relate VTCI with crop moisture status and crop performance. VTCI was found to accurately access the degree and spatial extent of drought stress in all years (2000, 2002, and 2004). The temporal variation of VTCI also provides drought pattern changes over space and time. Results showed significant and positive relations between CMI (crop moisture index) and VTCI observed particularly during prominent drought periods which proved VTCI as an ideal index to monitor terminal drought at regional scale. VTCI had significant positive relationship with yield but weakly related to crop anomalies. Duration of terminal drought stress derived from VTCI has a significant negative relationship with yields of major grain and oilseeds crops, particularly, groundnut. PMID:22200944

  11. Microwave vegetation indexes for detecting biomass and water conditions of agricultural crops

    International Nuclear Information System (INIS)

    Experimental and theoretical investigations have shown that microwave emission from canopies depends on crop type and physical conditions. However, since the sensitivity of the brightness temperature to vegetation parameters is rather low, accurate observations and suitable models are necessary to extract geophysical parameters from radiometer data. The most significant results, obtained over the past years on the basis of measurements carried out with passive microwave sensors at 10 GHz and 36 GHz, are summarized in this paper. The relations between the microwave vegetation indexes and plant biophysical parameters are discussed, using a simple slab model that considers vegetation as a uniform absorbing and scattering medium upon the soil surface. It is shown that simultaneous observations at 10 GHz and 36 GHz, in V and H polarizations, especially if combined with thermal infrared measurements, are useful in separating different crops and in identifying moisture conditions of the surfaces. The difference (?TN), between the normalized temperatures at 36 GHz and 10 GHz, and the polarization index (PI) at 10 GHz are functions of biomass and can be related to the leaf area index of some crops

  12. Assessments of Drought Impacts on Vegetation in China with the Optimal Time Scales of the Climatic Drought Index

    Directory of Open Access Journals (Sweden)

    Zheng Li

    2015-07-01

    Full Text Available Drought is expected to increase in frequency and severity due to global warming, and its impacts on vegetation are typically extensively evaluated with climatic drought indices, such as multi-scalar Standardized Precipitation Evapotranspiration Index (SPEI. We analyzed the covariation between the SPEIs of various time scales and the anomalies of the normalized difference vegetation index (NDVI, from which the vegetation type-related optimal time scales were retrieved. The results indicated that the optimal time scales of needle-leaved forest, broadleaf forest and shrubland were between 10 and 12 months, which were considerably longer than the grassland, meadow and cultivated vegetation ones (2 to 4 months. When the optimal vegetation type-related time scales were used, the SPEI could better reflect the vegetation’s responses to water conditions, with the correlation coefficients between SPEIs and NDVI anomalies increased by 5.88% to 28.4%. We investigated the spatio-temporal characteristics of drought and quantified the different responses of vegetation growth to drought during the growing season (April–October. The results revealed that the frequency of drought has increased in the 21st century with the drying trend occurring in most of China. These results are useful for ecological assessments and adapting management steps to mitigate the impact of drought on vegetation. They are helpful to employ water resources more efficiently and reduce potential damage to human health caused by water shortages.

  13. Sensitivity of leaf chlorophyll concentration of a broad-ban vegetation index at the canopy scale

    International Nuclear Information System (INIS)

    The development from a field spectrometric experiment of the chlorophyll vegetation index (CVI), a broad-band 6. sensitive to leaf chlorophyll concentration at the canopy scale, and of its optimized version (OCVI) are described. A single correction factor is incorporated in the OCVI algorithm to take into account the different spectral behaviours due to crop and soil types, sensor spectral resolution and scene sun zenith angle. The sensitivity of different broad-band 6., including CVI, to leaf cholophyll concentration is compared for a wide range of soils and crops conditions and for different sun zenith angles by the analysis of a PROSPECT+SAILH syntetic dataset

  14. RGB picture vegetation indexes for High-Throughput Phenotyping Platforms (HTPPs)

    Science.gov (United States)

    Kefauver, Shawn C.; El-Haddad, George; Vergara-Diaz, Omar; Araus, José Luis

    2015-10-01

    Extreme and abnormal weather events, as well as the more gradual meteorological changes associated with climate change, often coincide with not only increased abiotic risks (such as increases in temperature and decreases in precipitation), but also increased biotic risks due to environmental conditions that favor the rapid spread of crop pests and diseases. Durum wheat is by extension the most cultivated cereal in the south and east margins of the Mediterranean Basin. It is of strategic importance for Mediterranean agriculture to develop new varieties of durum wheat with greater production potential, better adaptation to increasingly adverse environmental conditions (drought) and better grain quality. Similarly, maize is the top staple crop for low-income populations in Sub-Saharan Africa and is currently suffering from the appearance of new diseases, which, together with increased abiotic stresses from climate change, are challenging the very sustainability of African societies. Current constraints in field phenotyping remain a major bottleneck for future breeding advances, but RGB-based High-Throughput Phenotyping Platforms (HTPPs) have shown promise for rapidly developing both disease-resistant and weather-resilient crops. RGB cameras have proven costeffective in studies assessing the effect of abiotic stresses, but have yet to be fully exploited to phenotype disease resistance. Recent analyses of durum wheat in Spain have shown RGB vegetation indexes to outperform multispectral indexes such as NDVI consistently in disease and yield prediction. Towards HTTP development for breeding maize disease resistance, some of the same RGB picture vegetation indexes outperformed NDVI (Normalized Difference Vegetation Index), with R2 values up to 0.65, compared to 0.56 for NDVI. . Specifically, hue, a*, u*, and Green Area (GA), as produced by FIJI and BreedPix open source software, performed similar to or better than NDVI in predicting yield and disease severity conditions for wheat and maize. Results using UAVs (Unmanned Aerial Vehicles) have produced similar results demonstrating the robust strengths, and limitations, of the more cost-effective RGB picture indexes.

  15. Evaluating the potential of vegetation indices for winter wheat LAI estimation under different fertilization and water conditions

    Science.gov (United States)

    Xie, Qiaoyun; Huang, Wenjiang; Dash, Jadunandan; Song, Xiaoyu; Huang, Linsheng; Zhao, Jinling; Wang, Renhong

    2015-12-01

    Leaf area index (LAI) is an important indicator for monitoring crop growth conditions and forecasting grain yield. Many algorithms have been developed for remote estimation of the leaf area index of vegetation, such as using spectral vegetation indices, inversion of radiative transfer models, and supervised learning techniques. Spectral vegetation indices, mathematical combination of reflectance bands, are widely used for LAI estimation due to their computational simplicity and their applications ranged from the leaf scale to the entire globe. However, in many cases, their applicability is limited to specific vegetation types or local conditions due to species specific nature of the relationship used to transfer the vegetation indices to LAI. The overall objective of this study is to investigate the most suitable vegetation index for estimating winter wheat LAI under eight different types of fertilizer and irrigation conditions. Regression models were used to estimate LAI using hyperspectral reflectance data from the Pushbroom Hyperspectral Imager (PHI) and in-situ measurements. Our results showed that, among six vegetation indices investigated, the modified soil-adjusted vegetation index (MSAVI) and the normalized difference vegetation index (NDVI) exhibited strong and significant relationships with LAI, and thus were sensitive across different nitrogen and water treatments. The modified triangular vegetation index (MTVI2) confirmed its potential on crop LAI estimation, although second to MSAVI and NDVI in our study. The enhanced vegetation index (EVI) showed moderate performance. However, the ratio vegetation index (RVI) and the modified simple ratio index (MSR) predicted the least accurate estimations of LAI, exposing the simple band ratio index's weakness under different treatment conditions. The results support the use of vegetation indices for a quick and effective LAI mapping procedure that is suitable for winter wheat under different management practices.

  16. Influence of winter wheat seed treatment by laser on vegetation period duration and harvest index of grain

    International Nuclear Information System (INIS)

    Influence of winter wheat seed stimulation by laser (cv. Radika) on the stages of development, duration of vegetation period and harvest index of grain was investigated. For dates of development stages advancing to heading, between cv. Radika and it's laser treatment weren't noticed significant differences. Noticable differences appear in stages of kernel filling and for duration of vegetation period. Treatments by laser were earlier in maturing from standard for 2-6 days depending of treatment and year. The harvest index of grain at laser treatments was significantly higher and depended from the conditions of year, too

  17. Assessments of Drought Impacts on Vegetation in China with the Optimal Time Scales of the Climatic Drought Index.

    Science.gov (United States)

    Li, Zheng; Zhou, Tao; Zhao, Xiang; Huang, Kaicheng; Gao, Shan; Wu, Hao; Luo, Hui

    2015-07-01

    Drought is expected to increase in frequency and severity due to global warming, and its impacts on vegetation are typically extensively evaluated with climatic drought indices, such as multi-scalar Standardized Precipitation Evapotranspiration Index (SPEI). We analyzed the covariation between the SPEIs of various time scales and the anomalies of the normalized difference vegetation index (NDVI), from which the vegetation type-related optimal time scales were retrieved. The results indicated that the optimal time scales of needle-leaved forest, broadleaf forest and shrubland were between 10 and 12 months, which were considerably longer than the grassland, meadow and cultivated vegetation ones (2 to 4 months). When the optimal vegetation type-related time scales were used, the SPEI could better reflect the vegetation's responses to water conditions, with the correlation coefficients between SPEIs and NDVI anomalies increased by 5.88% to 28.4%. We investigated the spatio-temporal characteristics of drought and quantified the different responses of vegetation growth to drought during the growing season (April-October). The results revealed that the frequency of drought has increased in the 21st century with the drying trend occurring in most of China. These results are useful for ecological assessments and adapting management steps to mitigate the impact of drought on vegetation. They are helpful to employ water resources more efficiently and reduce potential damage to human health caused by water shortages. PMID:26184243

  18. Spatio-temporal patterns in vegetation start of season across the island of Ireland using the MERIS Global Vegetation Index

    Science.gov (United States)

    O'Connor, Brian; Dwyer, Edward; Cawkwell, Fiona; Eklundh, Lars

    2012-03-01

    Spring phenophases such as the beginning of leaf unfolding, measured in the Irish gardens of the International Phenological Garden (IPG) network, indicate an earlier spring occurrence hence a longer growing season. However, these measurements are limited to selected species of trees at a few point locations in the southern half of the country. The aim of this study was to develop a methodology, based on satellite remote sensing, to measure the vegetation start of season (SOS) across the whole island of Ireland on an annual basis, complementary to existing ground-based methods. The SOS metric was extracted for each year in a 7-year time series of 10-day composited, 1.2 km reduced resolution MERIS Global Vegetation Index (MGVI) data from 2003 to 2009, based on curve fitting, using the time series analysis software, TIMESAT. Spatio-temporal variability in the SOS was detected across the island on an annual basis and highlighted in a series of anomaly images showing variation from the 7-year mean SOS. The 2006 SOS was late across the island while there were strong geographical gradients to the SOS anomalies in 2009 when it occurred later in the south and earlier in the north. There was a mix of early and late anomaly values throughout the country in the other years. Qualitatively, the spatial patterns in the timing of the SOS were related to the distribution of landcover types as indicated by the CORINE Land Cover map (CLC). Three statistically separable groups of CLC classes were derived from differences in the SOS, namely agricultural and forest land cover types, peat bogs, and natural and semi-natural vegetation types. These groups demonstrated that vegetation in cultivated areas like pastures has a significantly earlier SOS than in areas of unmanaged vegetation such as peat bogs. An initial climate analysis indicated that an anomalously cold winter and spring in 2005/2006 delayed the 2006 SOS countrywide; while a cold winter followed by a mild spring in 2009 caused considerable spatial variability in the 2009 SOS across the country, ranging from later SOS in the south to early SOS in the north. This study has demonstrated the utility of 10-day MGVI composites for derivation of an SOS metric which can be used as an indicator of spatial variability in vegetation seasonality and has highlighted how SOS varies according to landcover type. The availability of longer time series in the future will allow more focused studies on the sensitivity of the SOS metric to changes in climate as well as short term weather events.

  19. Analyzing Vegetation Change in an Elephant-Impacted Landscape Using the Moving Standard Deviation Index

    Directory of Open Access Journals (Sweden)

    Timothy J. Fullman

    2014-01-01

    Full Text Available Northern Botswana is influenced by various socio-ecological drivers of landscape change. The African elephant (Loxodonta africana is one of the leading sources of landscape shifts in this region. Developing the ability to assess elephant impacts on savanna vegetation is important to promote effective management strategies. The Moving Standard Deviation Index (MSDI applies a standard deviation calculation to remote sensing imagery to assess degradation of vegetation. Used previously for assessing impacts of livestock on rangelands, we evaluate the ability of the MSDI to detect elephant-modified vegetation along the Chobe riverfront in Botswana, a heavily elephant-impacted landscape. At broad scales, MSDI values are positively related to elephant utilization. At finer scales, using data from 257 sites along the riverfront, MSDI values show a consistent negative relationship with intensity of elephant utilization. We suggest that these differences are due to varying effects of elephants across scales. Elephant utilization of vegetation may increase heterogeneity across the landscape, but decrease it within heavily used patches, resulting in the observed MSDI pattern of divergent trends at different scales. While significant, the low explanatory power of the relationship between the MSDI and elephant utilization suggests the MSDI may have limited use for regional monitoring of elephant impacts.

  20. [Estimating canopy water content in wheat based on new vegetation water index].

    Science.gov (United States)

    Cheng, Xiao-juan; Yang, Gui-jun; Xu, Xin-gang; Chen, Tian-en; Li, Zhen-hai; Feng, Hai-kuan; Wang, Dong

    2014-12-01

    Moisture content is an important indicator for crop water stress condition, timely and effective monitoring crop water content is of great significance for evaluate crop water deficit balance and guide agriculture irrigation. In order to improve the saturated problems of different forms of typical NDWI (Normalized Different Water Index), we tried to introduce EVI (Enhanced Vegetation Index) to build new vegetation water indices (NDWI#) to estimate crop water content. Firstly, PROSAIL model was used to study the saturation sensitivity of NDWI, and NDWI# to canopy water content and LAI (Leaf Area Index). Then, the estimated model and verified model were estimated using the spectral data and moisture data in the field. The result showed that the new indices have significant relationships with canopy water content. In particular, by implementing modified standardized for NDWI1450, NDWI1940, NDWI2500. The result indicated that newly developed indices with visible-infrared and shortwave infrared spectral feature may have greater advantage for estimation winter canopy water content. PMID:25881445

  1. Generating Vegetation Leaf Area Index Earth System Data Record from Multiple Sensors. Part 1; Theory

    Science.gov (United States)

    Ganguly, Sangram; Schull, Mitchell A.; Samanta, Arindam; Shabanov, Nikolay V.; Milesi, Cristina; Nemani, Ramakrishna R.; Knyazikhin, Yuri; Myneni, Ranga B.

    2008-01-01

    The generation of multi-decade long Earth System Data Records (ESDRs) of Leaf Area Index (LAI) and Fraction of Photosynthetically Active Radiation absorbed by vegetation (FPAR) from remote sensing measurements of multiple sensors is key to monitoring long-term changes in vegetation due to natural and anthropogenic influences. Challenges in developing such ESDRs include problems in remote sensing science (modeling of variability in global vegetation, scaling, atmospheric correction) and sensor hardware (differences in spatial resolution, spectral bands, calibration, and information content). In this paper, we develop a physically based approach for deriving LAI and FPAR products from the Advanced Very High Resolution Radiometer (AVHRR) data that are of comparable quality to the Moderate resolution Imaging Spectroradiometer (MODIS) LAI and FPAR products, thus realizing the objective of producing a long (multi-decadal) time series of these products. The approach is based on the radiative transfer theory of canopy spectral invariants which facilitates parameterization of the canopy spectral bidirectional reflectance factor (BRF). The methodology permits decoupling of the structural and radiometric components and obeys the energy conservation law. The approach is applicable to any optical sensor, however, it requires selection of sensor-specific values of configurable parameters, namely, the single scattering albedo and data uncertainty. According to the theory of spectral invariants, the single scattering albedo is a function of the spatial scale, and thus, accounts for the variation in BRF with sensor spatial resolution. Likewise, the single scattering albedo accounts for the variation in spectral BRF with sensor bandwidths. The second adjustable parameter is data uncertainty, which accounts for varying information content of the remote sensing measurements, i.e., Normalized Difference Vegetation Index (NDVI, low information content), vs. spectral BRF (higher information content). Implementation of this approach indicates good consistency in LAI values retrieved from NDVI (AVHRRmode) and spectral BRF (MODIS-mode). Specific details of the implementation and evaluation of the derived products are detailed in the second part of this two-paper series.

  2. Recent Trends in Satellite Vegetation Index Observations Indicate Decreasing Vegetation Biomass in the Southeastern Saline Everglades Wetlands

    Science.gov (United States)

    Fuller, D. O.

    2013-12-01

    We analyzed trends in time series of the normalized difference vegetation index (NDVI) from multitemporal satellite imagery for 2001-2010 over the southeastern Everglades where major changes in vegetation structure and type have been associated with sea-level rise and reduced freshwater flow since the 1940s. Non-parametric trend analysis using the Theil-Sen slope revealed that 84.4% of statistically significant trends in NDVI were negative, mainly concentrated in scrub mangrove, sawgrass (Cladium jamaicense) and spike rush (Eleocharis cellulosa) communities within 5 km of the shoreline. Observed trends were consistent with trends in sawgrass biomass measurements made from 1999-2010 in three Long-term Ecological Research (LTER) sites within our study area. A map of significant trends overlaid on a RapidEye high-resolution satellite image showed large patches of negative trends parallel to the shoreline in and around the 'white zone,' which corresponds to a low-productivity band that has moved inland over the past 70 years. Significantly positive trends were observed mainly in the halophytic prairie community where highly salt tolerant species are typically found. Taken as a whole, the results suggest that increased saline intrusion associated with sea-level rise continues to reduce the photosynthetic biomass within freshwater and oligohaline marsh communities of the southeastern Everglades. Trends in 2001-2010 NDVI in southern saline Everglades wetlands of South Florida. a) slope values; b) areas of significant slope; c) location of the study area.

  3. Modified soil adjusted vegetation index for the Death Valley regional flow system, Nevada and California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The raster-based Modified Soil Adjusted Vegetation Index was derived from Landsat Thematic Mapper imagery data acquired during June 1992 for the Death Valley...

  4. Modified soil adjusted vegetation index of the Sarcobatus Flat area of the Death Valley

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The raster-based Modified Soil Adjusted Vegetation Index was derived from Landsat Thematic Mapper imagery data acquired during June 1989 for Sarcobatus Flat. The...

  5. Determination of phenological dates in boreal regions using Normalized Difference Water Index

    OpenAIRE

    Delbart, Nicolas; Kergoat, L.; Le Toan, Thuy; Lhermitte, J.; Picard, Ghislain

    2005-01-01

    Monitoring and understanding plant phenology is important in the context of studies of terrestrial productivity and global change. Vegetation phenology such as dates of onsets of greening up and leaf senescence have been determined by remote sensing using mainly the Normalized Difference Vegetation Index (NDVI). In boreal regions, the results suffer from significant uncertainties because of the effect of snow on NDVI. In this paper, SPOT VEGETATION S10 data over Siberia have been analysed to ...

  6. Global assessment of Vegetation Index and Phenology Lab (VIP) and Global Inventory Modeling and Mapping Studies (GIMMS) version 3 products

    Science.gov (United States)

    Marshall, M.; Okuto, E.; Kang, Y.; Opiyo, E.; Ahmed, M.

    2015-06-01

    Earth observation based long-term global vegetation index products are used by scientists from a wide range of disciplines concerned with global change. Inter-comparison studies are commonly performed to keep the user community informed on the consistency and accuracy of such records as they evolve. In this study, we compared two new records: (1) Global Inventory Modeling and Mapping Studies (GIMMS) Normalized Difference Vegetation Index Version 3 (NDVI3g) and (2) Vegetation Index and Phenology Lab (VIP) Version 3 NDVI (NDVI3v) and Enhanced Vegetation Index 2 (EVI3v). We evaluated the two records via three experiments that addressed the primary use of such records in global change research: (1) prediction of the Leaf Area Index (LAI) used in light-use efficiency modeling, (2) estimation of vegetation climatology in Soil-Vegetation-Atmosphere Transfer models, and (3) trend analysis of the magnitude and phenology of vegetation productivity. Experiment one, unlike previous inter-comparison studies, was performed with a unique Landsat 30 m spatial resolution and in situ LAI database for major crop types on five continents. Overall, the two records showed a high level of agreement both in direction and magnitude on a monthly basis, though VIP values were higher and more variable and showed lower correlations and higher error with in situ LAI. The records were most consistent at northern latitudes during the primary growing season and southern latitudes and the tropics throughout much of the year, while the records were less consistent at northern latitudes during green-up and senescence and in the great deserts of the world throughout much of the year. The two records were also highly consistent in terms of trend direction/magnitude, showing a 30+ year increase (decrease) in NDVI over much of the globe (tropical rainforests). The two records were less consistent in terms of timing due to the poor correlation of the records during start and end of growing season.

  7. The Vegetation Drought Response Index (VegDRI): A new integrated approach for monitoring drought stress in vegetation

    Science.gov (United States)

    Brown, J.F.; Wardlow, B.D.; Tadesse, T.; Hayes, M.J.; Reed, B.C.

    2008-01-01

    The development of new tools that provide timely, detailed-spatial-resolution drought information is essential for improving drought preparedness and response. This paper presents a new method for monitoring drought-induced vegetation stress called the Vegetation Drought Response Index (VegDRI). VegDRI integrates traditional climate-based drought indicators and satellite-derived vegetation index metrics with other biophysical information to produce a I km map of drought conditions that can be produced in near-real time. The initial VegDRI map results for a 2002 case study conducted across seven states in the north-central United States illustrates the utility of VegDRI for improved large-area drought monitoring. Copyright ?? 2008 by Bellwether Publishing, Ltd. All rights reserved.

  8. The effect of soil moisture on the 37 GHz microwave polarization difference index (MPDI)

    International Nuclear Information System (INIS)

    Previous studies have shown that the 37 GHz microwave polarization difference index (MPDI) has an inverse nonlinear relationship to the normalized difference vegetation index (NDVI) with the MPDI (NDVI) being more sensitive to vegetation density under sparse (moderate) vegetation conditions. It has also been noted that soil moisture can have a significant influence on the MPDI. This study quantifies the effect of soil moisture on the MPDI using the RADTRAN model and comparison with measurements from a few geographically restricted (eastern USA) study sites. Model results show the MPDI increases with soil moisture but its sensitivity approaches zero when soil moisture values or vegetation densities are large. Results based on special sensor microwave/imager (SSM/I) measured values of MPDI, using the NDVI as a surrogate for vegetation density and an antecedent precipitation index (API) as a surrogate for soil moisture, were consistent with those based on the model. Linear equations, one for each of three categories of vegetation density, expressing MPDI as a function of API were derived based on SSM/I measurements. These equations demonstrate that soil moisture information can be extracted from the MPDI when the NDVI is used to account for the effect of vegetation and that the effect of soil moisture on the MPDI should be taken into account if it is to be used as a vegetation index. The potential to normalize MPDI values for variations in soil moisture is discussed. (author)

  9. Value of Using Different Vegetative Indices to Quantify Agricultural Crop Characteristics at Different Growth Stages under Varying Management Practices

    Directory of Open Access Journals (Sweden)

    John H. Prueger

    2010-02-01

    Full Text Available The paper investigates the value of using distinct vegetation indices to quantify and characterize agricultural crop characteristics at different growth stages. Research was conducted on four crops (corn, soybean, wheat, and canola over eight years grown under different tillage practices and nitrogen management practices that varied rate and timing. Six different vegetation indices were found most useful, depending on crop phenology and management practices: (a simple ratio for biomass, (b NDVI for intercepted PAR, (c SAVI for early stages of LAI, (d EVI for later stages of LAI, (e CIgreen for leaf chlorophyll, (f NPCI for chlorophyll during later stages, and (g PSRI to quantify plant senescence. There were differences among varieties of corn and soybean for the vegetation indices during the growing season and these differences were a function of growth stage and vegetative index. These results clearly imply the need to use multiple vegetation indices to best capture agricultural crop characteristics.

  10. Estimating soil moisture from 6.6 GHz dual polarization, and/or satellite derived vegetation index

    International Nuclear Information System (INIS)

    Eight and a half years (January 1979 to August 1987) of Scanning Multichannel Microwave Radiometer (SMMR) data taken at a frequency of 6.6 GHz for both day and night observations at both polarizations were processed, documented and used to study the relationship between brightness temperature (T(B)) and antecedent precipitation index (API) in a wide range of vegetation index (normalized difference vegetation index (NDVI) varies from 0.2 to 0.6) in the mid-west and southern United States. In general, this study validates the model structure for soil wetness developed by Choudhury and Golus. For NDVI greater than 0.45 the resultant microwave signal is substantially affected by the vegetation. The night-time observations by both polarizations gave a better correlation between T(B) and API. The horizontal polarization is more sensitive to vegetation. For the least and greatest vegetated areas, night-time observations by vertical polarization showed less scatter in the T(B) versus API relation. A non-linear model was developed for soil wetness using horizontal and vertical polarization and their difference. The estimate of error for this model is better than previous models, and can be used to obtain six levels of soil moisture. (author)

  11. A Rapidly Prototyped Vegetation Dryness Index Developed for Wildfire Risk Assessment at Stennis Space Center

    Science.gov (United States)

    Ross, Kenton; Graham, William D.; Prados, Donald; Spruce, Joseph

    2006-01-01

    A remote sensing index was developed to allow improved monitoring of vegetation dryness conditions on a regional basis. This remote sensing index was rapidly prototyped at Stennis Space Center in response to drought conditions in the local area in spring 2006.

  12. Experimental testing of a volume index as a fast method for estimating carbon stock in the understorey vegetation

    Directory of Open Access Journals (Sweden)

    Chirici G

    2009-05-01

    Full Text Available The biomass of understory vegetation has an important role in several forest ecosystem processes, though it is not frequently included in forest inventory programs, which are commonly focused on the tree component. The objective of the study is to test a fast procedure for obtaining an accurate estimation of three components of the aboveground understory vegetation: herbaceous, bush, regeneration. For such a purpose a Volume Index has been calculated on the basis of the product between the percent coverage of vegetation and the average height of the three different components of understory vegetation. The index has been quantified in twenty clusters of four squared plots 1 m2 wide; clusters were located in two study areas in the northern part of Molise Region (southeastern Italy. For each plot, the dry biomass has been collected and weighted, and then transformed in carbon stock. This study presents the field protocol and the achieved results in terms of measured aboveground understorey carbon stock in six different forest and pre-forest types (the average carbon stock was 1.19 t C ha-1 and correlation between Volume Index and carbon stock (the Pearson’s correlation index was 0.8 on 309 field observations.

  13. Vegetation indices derived from a modified digital camera in combination with different blocking filters

    Science.gov (United States)

    Krainer, Karl; Hammerle, Albin; Wohlfahrt, Georg

    2015-04-01

    Remote and proximal sensing have become valuable and broadly used tools in ecosystem research. Radiation reflected and scattered at and from the vegetation is used to infer information about vegetation biomass, structure, vitality and functioning, just to name a few. To this end numerous vegetation indices have been established, which relate reflectance in different wavelengths to each other. While such indices are usually calculated from reflectance data measured by spectro-radiometers we did a study using a commercially available digital camera, from which the infrared (IR) band elimination filter was removed. By removing this filter, the camera sensor became sensitive for IR radiation besides the visible spectrum. Comparing measurements with this modified camera and a hyperspectral spectro-radiometer over different vegetation and surfaces we determined the potential of such a modified camera to measure different vegetation indices. To this end we compared 71 vegetation indices derived from spectro-radiometer data with 63 indices derived from the modified digital camera. We found that many of these different indices featured relatively high correlations. Especially the rgR (green/red ratio) and NDI (normalized difference vegetation index) calculated from data of the modified camera do correlate very well with vegetation indices that are known for representing the amount and vitality of green biomass, as these are the NIDI (normalized infrared vegetation index) and the LIC (curvature index). We thus conclude from this experiment, that given a proper inter-calibration, a commercially available digital camera can be modified and used as a reasonable alternative tool to determine vegetation biomass and/or vitality. In addition to these measurements currently different band elimination filters are used to improve the information content of the digital images.

  14. A simple interpretation of the surface temperature/vegetation index space for assessment of surface moisture status

    DEFF Research Database (Denmark)

    Sandholt, Inge; Rasmussen, Kjeld; Andersen, Jens Asger

    2002-01-01

    A simplified land surface dryness index (Temperature-Vegetation Dryness Index, TVDI) based on an empirical parameterisation of the relationship between surface temperature (T-s) and vegetation index (NDVI) is suggested. The index is related to soil moisture and, in comparison to existing interpretations of the T-s/NDVI space, the index is conceptually and computationally straightforward. It is based on satellite derived information only, and the potential for operational application of the index...

  15. Monitoring the vegetation start of season (SOS) across the island of Ireland using the MERIS global vegetation index

    OpenAIRE

    O'Connor, Brian

    2011-01-01

    The aim of this study was to develop a methodology, based on satellite remote sensing, to estimate the vegetation Start of Season (SOS) across the whole island of Ireland on an annual basis. This growing body of research is known as Land Surface Phenology (LSP) monitoring. The SOS was estimated for each year from a 7-year time series of 10-day composited, 1.2 km reduced resolution MERIS Global Vegetation Index (MGVI) data from 2003 to 2009, using the time series analysis software, TIMESAT. Th...

  16. Estimating Riparian and Agricultural Actual Evapotranspiration by Reference Evapotranspiration and MODIS Enhanced Vegetation Index

    Directory of Open Access Journals (Sweden)

    Russell L. Scott

    2013-08-01

    Full Text Available Dryland river basins frequently support both irrigated agriculture and riparian vegetation and remote sensing methods are needed to monitor water use by both crops and natural vegetation in irrigation districts. We developed an algorithm for estimating actual evapotranspiration (ETa based on the Enhanced Vegetation Index (EVI from the Moderate Resolution Imaging Spectrometer (MODIS sensor on the EOS-1 Terra satellite and locally-derived measurements of reference crop ET (ETo. The algorithm was calibrated with five years of ETa data from three eddy covariance flux towers set in riparian plant associations on the upper San Pedro River, Arizona, supplemented with ETa data for alfalfa and cotton from the literature. The algorithm was based on an equation of the form ETa = ETo [a(1 ? e?bEVI ? c], where the term (1 ? e?bEVI is derived from the Beer-Lambert Law to express light absorption by a canopy, with EVI replacing leaf area index as an estimate of the density of light-absorbing units. The resulting algorithm capably predicted ETa across riparian plants and crops (r2 = 0.73. It was then tested against water balance data for five irrigation districts and flux tower data for two riparian zones for which season-long or multi-year ETa data were available. Predictions were within 10% of measured results in each case, with a non-significant (P = 0.89 difference between mean measured and modeled ETa of 5.4% over all validation sites. Validation and calibration data sets were combined to present a final predictive equation for application across crops and riparian plant associations for monitoring individual irrigation districts or for conducting global water use assessments of mixed agricultural and riparian biomes.

  17. Monitoring Thermal Status of Ecosystems with MODIS Land-Surface Temperature and Vegetation Index Products

    Science.gov (United States)

    Wan, Zhengming

    2002-01-01

    The global land-surface temperature (LST) and normalized difference vegetation index (NDVI) products retrieved from Moderate Resolution Imaging Spectroradiometer (MODIS) data in 2001 were used in this study. The yearly peak values of NDVI data at 5km grids were used to define six NDVI peak zones from -0.2 to 1 in steps of 0.2, and the monthly NDVI values at each grid were sorted in decreasing order, resulting in 12 layers of NDVI images for each of the NDVI peak zones. The mean and standard deviation of daytime LSTs and day-night LST differences at the grids corresponding to the first layer of NDVI images characterize the thermal status of terrestrial ecosystems in the NDVI peak zones. For the ecosystems in the 0.8-1 NDVI peak zone, daytime LSTs distribute from 0-35 C and day-night LST differences distribute from -2 to 22 C. The daytime LSTs and day-night LST differences corresponding to the remaining layers of NDVI images show that the growth of vegetation is limited at low and high LSTs. LSTs and NDVI may be used to monitor photosynthetic activity and drought, as shown in their applications to a flood-irrigated grassland in California and an unirrigated grassland in Nevada.

  18. Global Cross-Comparison of Suomi NPP VIIRS Vegetation Index EDR with Aqua MODIS

    Science.gov (United States)

    Miura, T.; Tsend-Ayush, J.; Kato, A.; Vargas, M.

    2014-12-01

    The Visible Infrared Imaging Radiometer Suite (VIIRS) sensor series is slated to continue the highly calibrated data stream initiated with Earth Observing System (EOS) Moderate Resolution Imaging Spectroradiometer (MODIS). A number of geophysical products, termed Environmental Data Records (EDRs), are being produced from VIIRS data, including Vegetation Index (VI) EDR. VIIRS VI EDR is a daily, 375 m resolution product and includes the "Top-of-the-Atmosphere (TOA)" Normalized Difference Vegetation Index (NDVI) and the "Top-of-Canopy (TOC)" Enhanced Vegetation Index (EVI). The TOC NDVI is being added to the product. In this study, we cross-compared VI EDR from the first VIIRS sensor onboard the Suomi National Polar-orbiting Partnership (NPP) satellite platform with the Aqua MODIS counterparts in global scale with the aim of developing a thorough understanding of radiometric compatibility between the two VI datasets. VIIRS VI products from April 2014 through June 2014 were obtained along with MODIS daily products. They were all reprojected and spatially-aggregated into a 4 km sinusoidal grid while screening for cloud and aerosol contaminations using quality flags. We then masked VIIRS-MODIS observation pairs for near-identical observation geometry: (1) view zenith angle (VZA) mean differences (MDs) were computed for each VZA bin and for all bins at once for quantitative evaluation. VIIRS and MODIS TOA NDVI had a very small overall MD of 0.005 NDVI units, whereas TOC EVI had a fairly large overall MD of -0.04 EVI units. These systematic differences were consistent across the 2-month period examined in this study. TOC NDVI, on the other hand, had largely fluctuating MD across this period, ranging from 0.005 to 0.01 NDVI units, an indication of inconsistent atmospheric correction or cloud mask results. With respect to VZA, inconsistent MDs were always obtained for the 55-62.5 degree VZA bin for all the three indices. Overall, VIIRS and MODIS VI products are subject to systematic differences, which are however consistent for VZ < 50 degrees. Future studies should examine the performance of VIIRS atmospheric corrections and compatibility of VIIRS and MODIS observations at large VZA.

  19. [Characteristics of soil microbial community under different vegetation types in Wuyishan National Nature Reserve, East China].

    Science.gov (United States)

    Wu, Ze-yan; Lin, Wen-xiong; Chen, Zhi-fang; Fang, Chang-xun; Zhang, Zhi-xing; Wu, Lin-kun; Zhou, Ming-ming; Shen, Li-hua

    2013-08-01

    By using Biolog Ecoplate system, this paper studied the structure and functional diversity of soil microbial community under different vegetation types in Wuyishan National Nature Reserve, aimed to probe into the effects of vegetation type on the diversity of soil microbial community. The results showed that the soil chemical properties, soil enzyme activities, and average well color development (AWCD) were higher in natural forest than in planted forest, and were the lowest in abandoned field. The AWCD reflecting soil microbial activity and functional diversity was increased with increasing incubation time, but there existed significant differences among different vegetation types. The carbon sources mostly used by soil microbes were carbohydrates and carboxylic acids, followed by amino acids, phenolic acids and polymers, and amines had the lowest utilization rate. The Simpson index, Shannon index, Richness index and McIntosh index in natural forest were holistically higher than those in planted forest. Principal component analysis (PCA) identified 2 principal component factors in relation to carbon sources, explaining 56.3% and 30.2% of the variation, respectively. The carbon sources used by soil microbial community differed with vegetation types. Amino acids and amides were the two main carbon sources separating the 2 principal component factors. The results of this study could provide basis for further approaching the relationships between vegetation diversity and soil microbial community diversity. PMID:24380352

  20. Analyzing Vegetation Change in an Elephant-Impacted Landscape Using the Moving Standard Deviation Index

    OpenAIRE

    Timothy J. Fullman; Erin L. Bunting

    2014-01-01

    Northern Botswana is influenced by various socio-ecological drivers of landscape change. The African elephant (Loxodonta africana) is one of the leading sources of landscape shifts in this region. Developing the ability to assess elephant impacts on savanna vegetation is important to promote effective management strategies. The Moving Standard Deviation Index (MSDI) applies a standard deviation calculation to remote sensing imagery to assess degradation of vegetation. Used previously for asse...

  1. Marsh collapse thresholds for coastal Louisiana estimated using elevation and vegetation index data

    Science.gov (United States)

    Couvillion, Brady R.; Beck, Holly

    2013-01-01

    Forecasting marsh collapse in coastal Louisiana as a result of changes in sea-level rise, subsidence, and accretion deficits necessitates an understanding of thresholds beyond which inundation stress impedes marsh survival. The variability in thresholds at which different marsh types cease to occur (i.e., marsh collapse) is not well understood. We utilized remotely sensed imagery, field data, and elevation data to help gain insight into the relationships between vegetation health and inundation. A Normalized Difference Vegetation Index (NDVI) dataset was calculated using remotely sensed data at peak biomass (August) and used as a proxy for vegetation health and productivity. Statistics were calculated for NDVI values by marsh type for intermediate, brackish, and saline marsh in coastal Louisiana. Marsh-type specific NDVI values of 1.5 and 2 standard deviations below the mean were used as upper and lower limits to identify conditions indicative of collapse. As marshes seldom occur beyond these values, they are believed to represent a range within which marsh collapse is likely to occur. Inundation depth was selected as the primary candidate for evaluation of marsh collapse thresholds. Elevation relative to mean water level (MWL) was calculated by subtracting MWL from an elevation dataset compiled from multiple data types including light detection and ranging (lidar) and bathymetry. A polynomial cubic regression was used to examine a random subset of pixels to determine the relationship between elevation (relative to MWL) and NDVI. The marsh collapse uncertainty range values were found by locating the intercept of the regression line with the 1.5 and 2 standard deviations below the mean NDVI value for each marsh type. Results indicate marsh collapse uncertainty ranges of 30.7–35.8 cm below MWL for intermediate marsh, 20–25.6 cm below MWL for brackish marsh, and 16.9–23.5 cm below MWL for saline marsh. These values are thought to represent the ranges of inundation depths within which marsh collapse is probable.

  2. Normalized-Difference Snow Index (NDSI)

    Science.gov (United States)

    Hall, Dorothy K.; Riggs, George A.

    2010-01-01

    The Normalized-Difference Snow Index (NDSI) has a long history. 'The use of ratioing visible (VIS) and near-infrared (NIR) or short-wave infrared (SWIR) channels to separate snow and clouds was documented in the literature beginning in the mid-1970s. A considerable amount of work on this subject was conducted at, and published by, the Air Force Geophysics Laboratory (AFGL). The objective of the AFGL work was to discriminate snow cover from cloud cover using an automated algorithm to improve global cloud analyses. Later, automated methods that relied on the VIS/NIR ratio were refined substantially using satellite data In this section we provide a brief history of the use of the NDSI for mapping snow cover.

  3. Combining vegetation index and model inversion methods for theextraction of key vegetation biophysical parameters using Terra and Aqua MODIS reflectance data

    DEFF Research Database (Denmark)

    Houborg, Rasmus Møller; Søgaard, Henrik; Bøgh, Eva

    2007-01-01

    Accurate estimates of vegetation biophysical variables are valuable as input to models describing the exchange of carbon dioxide and energy between the land surface and the atmosphere and important for a wide range of applications related to vegetation monitoring, weather prediction, and climate change. The present study explores the benefits of combining vegetation index and physically based approaches for the spatial and temporal mapping of green leaf area index (LAI), total chlorophyll conten...

  4. RELATIONSHIP BETWEEN REDNESS INDEX OF SOIL AND CARBON STOCK OF AERIAL BIOMASS IN CERRADO VEGETATION

    Directory of Open Access Journals (Sweden)

    Otacilio Antunes Santana

    2013-12-01

    Full Text Available http://dx.doi.org/10.5902/1980509812362The color variety of soil is response of its physical, chemical, biological and mineralogical composition. The Munsell color system is based on an objective color evaluation in which it is possible to evaluate different color soil factors such as the presence of iron oxides, particle size, and accumulated organic material. The objective of this study was to identify the relation between the redness index (IAV of soil and the amount of carbon content present in the aerial part of Cerrado vegetation. The study was conducted in seven cities in western Bahia state, in native areas of Cerrado. The determination o soil color was made in the field, with moist soil samples, using the Munsell color chart. From the evaluation of hue, value and chroma, the redness index (IAV was calculated. The estimation of carbon stock above ground was carried out from: trunk and branches, both living and dead trees by the allometric equation developed in Cerrado areas. The redness index of soil, from the layer 0.00 to 0.20 m, has a significant and directly proportional relationship with the carbon stock of above ground biomass of Cerrado vegetation. This may be extrapolated to calculate the carbon stock (EC by the redness index (IAV of soil by the equation [EC = 0.4936 · IAV + 4.2286 (-1.5%]. The practicality of sampling of data by IAV with Munsell chart, and the reliability of data fit by results of residual error less than 5%, make that this relationship may be used for academic and corporative in carbon stocks estimation for use in forest and environmental management. The EC variation between the studied physiognomies is mainly by distinct density of tree individuals per hectare. The variation of IAV in studied areas is due to the accumulated organic matter on the soil surface, the mineral content and drainage capacity, according to inferences of literature, and this reflecting the different colors of soil in the studied phytophysiognomies.

  5. Tropical forest biomass and successional age class relationships to a vegetation index derived from Landsat TM data

    Science.gov (United States)

    Sader, Steven A.; Waide, Robert B.; Lawrence, William T.; Joyce, Armond T.

    1989-01-01

    Forest stand structure and biomass data were collected using conventional forest inventory techniques in tropical, subtropical, and warm temperate forest biomes. The feasibility of detecting tropical forest successional age class and total biomass differences using Landsat-Thematic mapper (TM) data, was evaluated. The Normalized Difference Vegetation Index (NDVI) calculated from Landsat-TM data were not significantly correlated with forest regeneration age classes in the mountain terrain of the Luquillo Experimental Forest, Puerto Rico. The low sun angle and shadows cast on steep north and west facing slopes reduced spectral reflectance values recorded by TM orbital altitude. The NDVI, calculated from low altitude aircraft scanner data, was significatly correlated with forest age classes. However, analysis of variance suggested that NDVI differences were not detectable for successional forests older than approximately 15-20 years. Also, biomass differences in young successional tropical forest were not detectable using the NDVI. The vegetation index does not appear to be a good predictor of stand structure variables (e.g., height, diameter of main stem) or total biomass in uneven age, mixed broadleaf forest. Good correlation between the vegetation index and low biomass in even age pine plantations were achieved for a warm temperate study site. The implications of the study for the use of NDVI for forest structure and biomass estimation are discussed.

  6. Trends in a satellite-derived vegetation index and environmental variables in a restored brackish lagoon

    Directory of Open Access Journals (Sweden)

    Ji Yoon Kim

    2015-07-01

    Full Text Available We evaluated relative influence of climatic variables on the plant productivity after lagoon restoration. Chilika Lagoon, the largest brackish lake ecosystem in East Asia, experienced severe problems such as excessive dominance of freshwater exotic plants and rapid debasement of biodiversity associated with decreased hydrologic connectivity between the lagoon and the ocean. To halt the degradation of the lagoon ecosystem, the Chilika Development Authority implemented a restoration project, creating a new channel to penetrate the barrier beach of the lagoon. Using a satellite-derived normalized difference vegetation index (NDVI dataset, we compared the trend of vegetation changes after the lagoon restoration, from April 1998 to May 2014. The time series of NDVI data were decomposed into trend, seasonal, and random components using a local regression method. The results were visualized to understand the traits of spatial distribution in the lagoon. The NDVI trend, indicative of primary productivity, decreased rapidly during the restoration period, and gradually increased (slope coefficient: 2.1×10?4, p<0.05 after two years of restoration. Level of seawater exchange had more influences on plant productivity than local precipitation in the restored lagoon. Higher El Niño/Southern Oscillation increased sea level pressure, and caused intrusion of seawater into the lagoon, and the subsequently elevated salinity decreased the annual mean NDVI. Our findings suggest that lagoon restoration plans for enhancing interconnectivity with the ocean should consider oceanographic effects due to meteorological forcing, and long-term NDVI results can be used as a valuable index for adaptive management of the restoration site.

  7. VIP Data Explorer: A Tool for Exploring 30 years of Vegetation Index and Phenology Observations

    Science.gov (United States)

    Barreto-munoz, A.; Didan, K.; Rivera-Camacho, J.; Yitayew, M.; Miura, T.; Tsend-Ayush, J.

    2011-12-01

    Continuous acquisition of global satellite imagery over the years has contributed to the creation of long term data records from AVHRR, MODIS, TM, SPOT-VGT and other sensors. These records account for 30+ years, as these archives grow, they become invaluable tools for environmental, resources management, and climate studies dealing with trends and changes from local, regional to global scale. In this project, the Vegetation Index and Phenology Lab (VIPLab) is processing 30 years of daily global surface reflectance data into an Earth Science Data Record of Vegetation Index and Phenology metrics. Data from AVHRR (N07,N09,N11 and N14) and MODIS (AQUA and TERRA collection 5) for the periods 1981-1999 and 2000-2010, at CMG resolution were processed into one seamless and sensor independent data record using various filtering, continuity and gap filling techniques (Tsend-Ayush et al., AGU 2011, Rivera-Camacho et al, AGU 2011). An interactive online tool (VIP Data Explorer) was developed to support the visualization, qualitative and quantitative exploration, distribution, and documentation of these records using a simple web 2.0 interface. The VIP Data explorer (http://vip.arizona.edu/viplab_data_explorer) can display any combination of multi temporal and multi source data, enable the quickly exploration and cross comparison of the various levels of processing of this data. It uses the Google Earth (GE) model and was developed using the GE API for images rendering, manipulation and geolocation. These ESDRs records can be quickly animated in this environment and explored for visual trends and anomalies detection. Additionally the tool enables extracting and visualizing any land pixel time series while showing the different levels of processing it went through. User can explore this ESDR database within this data explorer GUI environment, and any desired data can be placed into a dynamic "cart" to be ordered and downloaded later. More functionalities are planned and will be added to this data explorer tool as the project progresses.

  8. Nutritional yield: a proposed index for fresh food improvement illustrated with leafy vegetable data.

    Science.gov (United States)

    Bumgarner, Natalie R; Scheerens, Joseph C; Kleinhenz, Matthew D

    2012-09-01

    Consumer interest in food products, including fresh vegetables, with health promoting properties is rising. In fresh vegetables, these properties include vitamins, minerals, dietary fiber, and secondary compounds, which collectively impart a large portion of the dietary, nutritional or health value associated with vegetable intake. Many, including farmers, aim to increase the health-promoting properties of fresh vegetables on the whole but they face at least three obstacles. First, describing crop composition in terms of its nutrition-based impact on human health is complex and there are few, if any, accepted processes and associated metrics for assessing and managing vegetable composition on-farm, at the origin of supply. Second, data suggest that primary and secondary metabolism can be 'in conflict' when establishing the abundance versus composition of a crop. Third, fresh vegetable farmers are rarely compensated for the phytochemical composition of their product. The development and implementation of a fresh vegetable 'nutritional yield' index could be instrumental in overcoming these obstacles. Nutritional yield is a function of crop biomass and tissue levels of health-related metabolites, including bioavailable antioxidant potential. Data from a multi-factor study of leaf lettuce primary and secondary metabolism and the literature suggest that antioxidant yield is sensitive to genetic and environmental production factors, and that changes in crop production and valuation will be required for fresh vegetable production systems to become more focused and purposeful instruments of public health. PMID:22922881

  9. Biobased polyurethanes prepared from different vegetable oils.

    Science.gov (United States)

    Zhang, Chaoqun; Madbouly, Samy A; Kessler, Michael R

    2015-01-21

    In this study, a series of biobased polyols were prepared from olive, canola, grape seed, linseed, and castor oil using a novel, solvent/catalyst-free synthetic method. The biobased triglyceride oils were first oxidized into epoxidized vegetable oils with formic acid and hydrogen peroxide, followed by ring-opening reaction with castor oil fatty acid. The molecular structures of the polyols and the resulting polyurethane were characterized. The effects of cross-linking density and the structures of polyols on the thermal, mechanical, and shape memory properties of the polyurethanes were also investigated. PMID:25541678

  10. Effects of vegetation types on soil moisture estimation from the normalized land surface temperature versus vegetation index space

    Science.gov (United States)

    Zhang, Dianjun; Zhou, Guoqing

    2015-12-01

    Soil moisture (SM) is a key variable that has been widely used in many environmental studies. Land surface temperature versus vegetation index (LST-VI) space becomes a common way to estimate SM in optical remote sensing applications. Normalized LST-VI space is established by the normalized LST and VI to obtain the comparable SM in Zhang et al. (Validation of a practical normalized soil moisture model with in situ measurements in humid and semiarid regions [J]. International Journal of Remote Sensing, DOI: 10.1080/01431161.2015.1055610). The boundary conditions in the study were set to limit the point A (the driest bare soil) and B (the wettest bare soil) for surface energy closure. However, no limitation was installed for point D (the full vegetation cover). In this paper, many vegetation types are simulated by the land surface model - Noah LSM 3.2 to analyze the effects on soil moisture estimation, such as crop, grass and mixed forest. The locations of point D are changed with vegetation types. The normalized LST of point D for forest is much lower than crop and grass. The location of point D is basically unchanged for crop and grass.

  11. The effect of bi-directional reflectance distribution function on the estimation of vegetation indices and leaf area index (LAI): A case study of the vegetation in succession stages after forest fire in northwestern Canada

    International Nuclear Information System (INIS)

    The effect of the dependence of the satellite data on sun/sensor geometry must be considered in the case of monitoring vegetation from satellites. Vegetation structure causes uneven scattering of sunlight, which is expressed by bi-directional reflectance distribution function (BRDF). The purpose of this study is to estimate the effect of BRDF of monitoring vegetation using the reflectance of visible and near-infrared bands. We investigated the vegetation in succession stages after forest fire (main species: spruce) in the northwestern Canada. BRF (Bidirectional Reflectance Factor) was measured in the seven sites of some succession stages, along with the measurements of leaf area index (LAI) and biomass. The main results obtained in this study are summarized as follows. (1) In each site, the difference of Normalized Difference Vegetation Index (NDVI) value around 0.1-0.2 was caused by BRDF when the sensor angle was changed from -15deg to 15 deg, being equivalent to the standard image of IKONOS. Also, LAI estimated by NDVI varied from 22% to 65% of the average. (2) The robustness of other vegetation indices to BRDF was compared. The reflectance of the near-infrared band normalized by the sum of other bands (nNIR), and Global Environmental Monitoring Index (GEMI) were investigated along with NDVI. It is clarified that nNIR was most robust in the site where vegetation existed. GEMI was most robust in the sites of scarce vegetation, while NDVI was strongly affected by BRDF in such sites

  12. Remote sensing of Japanese beech forest decline using an improved Temperature Vegetation Dryness Index (iTVDI

    Directory of Open Access Journals (Sweden)

    Ishimura A

    2011-11-01

    Full Text Available The Tanzawa Mountains, which cover parts of Kanagawa, Yamanashi and Shizuoka prefectures in Japan, are known for their natural beech forests. Since the 1980s, decline of the beech forests, probably caused by air pollution, water stress and insect infestation, has become a serious problem. We estimated the natural beech forest mortality rate in the mountains by using multi-temporal 8-day composite data recorded at the MODIS instrument aboard the Terra satellite, daily air temperature data at meteorological stations (AMeDAS in 2007, and a global digital elevation model obtained from ASTER aboard the Terra satellite. For the estimation, we used a Normalized Difference Vegetation Index (NDVI indicating the vegetation density, a Temperature Vegetation Dryness Index (TVDI, and an improved TVDI (iTVDI indicating the differences in transpiration rates between areas of similar vegetation density. We compared the NDVI, TVDI, and iTVDI maps with an existing mortality map of beech forests in the study area to verify their accuracy. To produce iTVDI maps, we calculated maps of air temperature by using ambient air temperature and elevation data. By interpolation using an environmental lapse rate, we calibrated air temperature maps with good accuracy (RMSE = 0.49 °C. The iTVDI map could detect mortality more accurately than the NDVI and TVDI maps in both spring and summer. Use of iTVDI enabled us to detect forest decline caused by air pollution and water deficits, inducing a reduction in transpiration rates. This index should be useful for monitoring vegetation decline.

  13. Vegetation biomass, leaf area index, and NDVI patterns and relationships along two latitudinal transects in arctic tundra

    Science.gov (United States)

    Epstein, H. E.; Walker, D. A.; Raynolds, M. K.; Kelley, A. M.; Jia, G.; Ping, C.; Michaelson, G.; Leibman, M. O.; Kaarlejärvi, E.; Khomutov, A.; Kuss, P.; Moskalenko, N.; Orekhov, P.; Matyshak, G.; Forbes, B. C.; Yu, Q.

    2009-12-01

    Analyses of vegetation properties along climatic gradients provide first order approximations as to how vegetation might respond to a temporally dynamic climate. Until recently, no systematic study of tundra vegetation had been conducted along bioclimatic transects that represent the full latitudinal extent of the arctic tundra biome. Since 1999, we have been collecting data on arctic tundra vegetation and soil properties along two such transects, the North American Arctic Transect (NAAT) and the Yamal Arctic Transect (YAT). The NAAT spans the arctic tundra from the Low Arctic of the North Slope of Alaska to the polar desert of Cape Isachsen on Ellef Ringnes Island in the Canadian Archipelago. The Yamal Arctic Transect located in northwest Siberia, Russia, presently ranges from the forest-tundra transition at Nadym to the High Arctic tundra on Belyy Ostrov off the north coast of the Yamal Peninsula. The summer warmth indices (SWI - sum of mean monthly temperatures greater than 0°C) range from approximately 40 °C months to 3 °C months from south to north. For largely zonal sites along these transects, we systematically collected leaf area index (LAI-2000 Plant Canopy Analyzer), normalized difference vegetation index (NDVI - PSII hand-held spectro-radiometer), and vegetation biomass (clip harvests). Site-averaged LAI ranges from 1.08 to 0 along the transects, yet can be highly variable at the landscape scale. Site-averaged NDVI ranges from 0.67 to 0.26 along the transects, and is less variable than LAI at the landscape scale. Total aboveground live biomass ranges from approximately 700 g m-2 to < 50 g m-2 along the NAAT, and from approximately 1100 g m-2 to < 400 g m-2 along the YAT (not including tree biomass at Nadym). LAI and NDVI are highly correlated logarithmically (r = 0.80) for the entire dataset. LAI is significantly related to total aboveground (live plus dead) vascular plant biomass, although there is some variability in the data (r = 0.63). NDVI is strongly correlated as a power function with photosynthetic biomass (r = 0.81). In general, for the same bioclimate subzone, total aboveground live biomass is substantially greater on the YAT compared to the NAAT. Some of this difference can be accounted for by the differences in measured non-vascular biomass. Since reindeer grazing on the Yamal Peninsula should reduce vegetation biomass to a greater extent than caribou grazing in North America, grazing differences are likely not responsible for biomass differences. However, different glacial and disturbance histories, soil substrates, and the resultant nutrient cycling processes could be hypothesized to yield these differences in vegetation biomass.

  14. Cooling parameters for fruits and vegetables of different sizes in a hydrocooling system

    Directory of Open Access Journals (Sweden)

    Teruel Bárbara

    2004-01-01

    Full Text Available The cooling of fruits and vegetables in hydrocooling system can be a suitable technique. This work aimed to define cooling time for fruits and vegetables of different sizes, presenting practical indexes that could be used to estimate cooling time for produce with similar characteristics. Fruits (orange melon-Cucumis melo, mango-Mangifera indica, guava-Psidium guajava, orange-Citrus sinensis Osbeck, plum-Prunus domestica, lime-Citrus limon, and acerola-Prunus cerasus and vegetables (cucumber-Cucumis sativus, carrot-Daucus carota, and green bean-Phaseolus vulgaris, were cooled in a hydrocooling system at 1°C. The volume of fruits and vegetables ranged between 8.18 cm³ and 1,150.35 cm³, and between 13.06 cm³ and 438.4 cm³, respectively. Cooling time varied proportionally to produce volume (from 8.5 to 124 min for fruits, and from 1.5 to 55 min, for vegetables. The relationship between volume and time needed to cool fruits (from 1.03 min cm-3 to 0.107 min cm-3 and vegetables (from 0.06 min cm-3 to 0.12 min cm-3 is an index that could be used to estimate cooling time for fruits and vegetables with similar dimensions as those presented in this work.

  15. Wheat Yield Forecasting for Punjab Province from Vegetation Index Time Series and Historic Crop Statistics

    Directory of Open Access Journals (Sweden)

    Jan Dempewolf

    2014-10-01

    Full Text Available Policy makers, government planners and agricultural market participants in Pakistan require accurate and timely information about wheat yield and production. Punjab Province is by far the most important wheat producing region in the country. The manual collection of field data and data processing for crop forecasting by the provincial government requires significant amounts of time before official reports can be released. Several studies have shown that wheat yield can be effectively forecast using satellite remote sensing data. In this study, we developed a methodology for estimating wheat yield and area for Punjab Province from freely available Landsat and MODIS satellite imagery approximately six weeks before harvest. Wheat yield was derived by regressing reported yield values against time series of four different peak-season MODIS-derived vegetation indices. We also tested deriving wheat area from the same MODIS time series using a regression-tree approach. Among the four evaluated indices, WDRVI provided more consistent and accurate yield forecasts compared to NDVI, EVI2 and saturation-adjusted normalized difference vegetation index (SANDVI. The lowest RMSE values at the district level for forecast versus reported yield were found when using six or more years of training data. Forecast yield for the 2007/2008 to 2012/2013 growing seasons were within 0.2% and 11.5% of final reported values. Absolute deviations of wheat area and production forecasts from reported values were slightly greater compared to using the previous year's or the three- or six-year moving average values, implying that 250-m MODIS data does not provide sufficient spatial resolution for providing improved wheat area and production forecasts.

  16. Global assessment of Vegetation Index and Phenology Lab (VIP) and Global Inventory Modeling and Mapping Studies (GIMMS) version 3 products

    Science.gov (United States)

    Marshall, M.; Okuto, E.; Kang, Y.; Opiyo, E.; Ahmed, M.

    2016-02-01

    Earth observation-based long-term global vegetation index products are used by scientists from a wide range of disciplines concerned with global change. Inter-comparison studies are commonly performed to keep the user community informed on the consistency and accuracy of such records as they evolve. In this study, we compared two new records: (1) Global Inventory Modeling and Mapping Studies (GIMMS) normalized difference vegetation index version 3 (NDVI3g) and (2) Vegetation Index and Phenology Lab (VIP) version 3 NDVI (NDVI3v) and enhanced vegetation index 2 (EVI3v). We evaluated the two records via three experiments that addressed the primary use of such records in global change research: (1) leaf area index (LAI), (2) vegetation climatology, and (3) trend analysis of the magnitude and timing of vegetation productivity. Unlike previous global studies, a unique Landsat 30 m spatial resolution and in situ LAI database for major crop types on five continents was used to evaluate the performance of not only NDVI3g and NDVI3v but also EVI3v. The performance of NDVI3v and EVI3v was worse than NDVI3g using the in situ data, which was attributed to the fusion of GIMMS and MODIS data in the VIP record. EVI3v has the potential to contribute biophysical information beyond NDVI3g and NDVI3v to global change studies, but we caution its use due to the poor performance of EVI3v in this study. Overall, the records were most consistent at northern latitudes during the primary growing season and southern latitudes and the tropics throughout much of the year, while the records were less consistent at northern latitudes during green-up and senescence, and in the great deserts of the world throughout much of the year. These patterns led to general agreement (disagreement) between trends in the magnitude (timing) of NDVI over the study period. Bias in inter-calibration of the VIP record at northernmost latitudes was suspected to contribute most to these discrepancies.

  17. Predicting maize yield in Zimbabwe using dry dekads derived from remotely sensed Vegetation Condition Index

    Science.gov (United States)

    Kuri, Farai; Murwira, Amon; Murwira, Karin S.; Masocha, Mhosisi

    2014-12-01

    Maize is a key crop contributing to food security in Southern Africa yet accurate estimates of maize yield prior to harvesting are scarce. Timely and accurate estimates of maize production are essential for ensuring food security by enabling actionable mitigation strategies and policies for prevention of food shortages. In this study, we regressed the number of dry dekads derived from VCI against official ground-based maize yield estimates to generate simple linear regression models for predicting maize yield throughout Zimbabwe over four seasons (2009-10, 2010-11, 2011-12, and 2012-13). The VCI was computed using Normalized Difference Vegetation Index (NDVI) time series dataset from the SPOT VEGETATION sensor for the period 1998-2013. A significant negative linear relationship between number of dry dekads and maize yield was observed in each season. The variation in yield explained by the models ranged from 75% to 90%. The models were evaluated with official ground-based yield data that was not used to generate the models. There is a close match between the predicted yield and the official yield statistics with an error of 33%. The observed consistency in the negative relationship between number of dry dekads and ground-based estimates of maize yield as well as the high explanatory power of the regression models suggest that VCI-derived dry dekads could be used to predict maize yield before the end of the season thereby making it possible to plan strategies for dealing with food deficits or surpluses on time.

  18. Generating Vegetation Leaf Area Index Earth System Data Record from Multiple Sensors. Part 2; Implementation, Analysis and Validation

    Science.gov (United States)

    Ganguly, Sangram; Samanta, Arindam; Schull, Mitchell A.; Shabanov, Nikolay V.; Milesi, Cristina; Nemani, Ramajrushna R,; Knyazikhin, Yuri; Myneni, Ranga B.

    2008-01-01

    The evaluation of a new global monthly leaf area index (LAI) data set for the period July 1981 to December 2006 derived from AVHRR Normalized Difference Vegetation Index (NDVI) data is described. The physically based algorithm is detailed in the first of the two part series. Here, the implementation, production and evaluation of the data set are described. The data set is evaluated both by direct comparisons to ground data and indirectly through inter-comparisons with similar data sets. This indirect validation showed satisfactory agreement with existing LAI products, importantly MODIS, at a range of spatial scales, and significant correlations with key climate variables in areas where temperature and precipitation limit plant growth. The data set successfully reproduced well-documented spatio-temporal trends and inter-annual variations in vegetation activity in the northern latitudes and semi-arid tropics. Comparison with plot scale field measurements over homogeneous vegetation patches indicated a 7% underestimation when all major vegetation types are taken into account. The error in mean values obtained from distributions of AVHRR LAI and high-resolution field LAI maps for different biomes is within 0.5 LAI for six out of the ten selected sites. These validation exercises though limited by the amount of field data, and thus less than comprehensive, indicated satisfactory agreement between the LAI product and field measurements. Overall, the intercomparison with short-term LAI data sets, evaluation of long term trends with known variations in climate variables, and validation with field measurements together build confidence in the utility of this new 26 year LAI record for long term vegetation monitoring and modeling studies.

  19. [Estimation and Visualization of Nitrogen Content in Citrus Canopy Based on Two Band Vegetation Index (TBVI)].

    Science.gov (United States)

    Wang, Qiao-nan; Ye, Xu-jun; Li, Jin-meng; Xiao, Yu-zhao; He, Yong

    2015-03-01

    Nitrogen is a necessary and important element for the growth and development of fruit orchards. Timely, accurate and nondestructive monitoring of nitrogen status in fruit orchards would help maintain the fruit quality and efficient production of the orchard, and mitigate the pollution of water resources caused by excessive nitrogen fertilization. This study investigated the capability of hyperspectral imagery for estimating and visualizing the nitrogen content in citrus canopy. Hyperspectral images were obtained for leaf samples in laboratory as well as for the whole canopy in the field with ImSpector V10E (Spectral Imaging Ltd., Oulu, Finland). The spectral datas for each leaf sample were represented by the average spectral data extracted from the selected region of interest (ROI) in the hyperspectral images with the aid of ENVI software. The nitrogen content in each leaf sample was measured by the Dumas combustion method with the rapid N cube (Elementar Analytical, Germany). Simple correlation analysis and the two band vegetation index (TBVI) were then used to develop the spectra data-based nitrogen content prediction models. Results obtained through the formula calculation indicated that the model with the two band vegetation index (TBVI) based on the wavelengths 811 and 856 nm achieved the optimal estimation of nitrogen content in citrus leaves (R2 = 0.607 1). Furthermore, the canopy image for the identified TBVI was calculated, and the nitrogen content of the canopy was visualized by incorporating the model into the TBVI image. The tender leaves, middle-aged leaves and elder leaves showed distinct nitrogen status from highto low-levels in the canopy image. The results suggested the potential of hyperspectral imagery for the nondestructive detection and diagnosis of nitrogen status in citrus canopy in real time. Different from previous studies focused on nitrogen content prediction at leaf level, this study succeeded in predicting and visualizing the nutrient content of fruit trees at canopy level. This would provide valuable information for the implementation of individual tree-based fertilization schemes in precision orchard management practices. PMID:26117885

  20. Global trends in vegetation phenology from 32-year GEOV1 leaf area index time series

    Science.gov (United States)

    Verger, Aleixandre; Baret, Frédéric; Weiss, Marie; Filella, Iolanda; Peñuelas, Josep

    2013-04-01

    Phenology is a critical component in understanding ecosystem response to climate variability. Long term data records from global mapping satellite platforms are valuable tools for monitoring vegetation responses to climate change at the global scale. Phenology satellite products and trend detection from satellite time series are expected to contribute to improve our understanding of climate forcing on vegetation dynamics. The capacity of monitoring ecosystem responses to global climate change was evaluated in this study from the 32-year time series of global Leaf Area Index (LAI) which have been recently produced within the geoland2 project. The long term GEOV1 LAI products were derived from NOAA/AVHRR (1981 to 2000) and SPOT/VGT (1999 to the present) with specific emphasis on consistency and continuity. Since mid-November, GEOV1 LAI products are freely available to the scientific community at geoland2 portal (www.geoland2.eu/core-mapping-services/biopar.html). These products are distributed at a dekadal time step for the period 1981-2000 and 2000-2012 at 0.05° and 1/112°, respectively. The use of GEOV1 data covering a long time period and providing information at dense time steps are expected to increase the reliability of trend detection. In this study, GEOV1 LAI time series aggregated at 0.5° spatial resolution are used. The CACAO (Consistent Adjustment of the Climatology to Actual Observations) method (Verger et al, 2013) was applied to characterize seasonal anomalies as well as identify trends. For a given pixel, CACAO computes, for each season, the time shift and the amplitude difference between the current temporal profile and the climatology computed over the 32 years. These CACAO parameters allow quantifying shifts in the timing of seasonal phenology and inter-annual variations in magnitude as compared to the average climatology. Interannual variations in the timing of the Start of Season and End of Season, Season Length and LAI level in the peak of the growing season are analyzed. Trend analysis with robust statistical test of significance is conducted. Climate variables (precipitation, temperature, radiation) are then used to interpret the anomaly patterns detected in vegetation response.

  1. Growing Degree Vegetation Production Index (GDVPI): A Novel and Data-Driven Approach to Delimit Season Cycles

    Science.gov (United States)

    Graham, W. D.; Spruce, J.; Ross, K. W.; Gasser, J.; Grulke, N.

    2014-12-01

    Growing Degree Vegetation Production Index (GDVPI) is a parametric approach to delimiting vegetation seasonal growth and decline cycles using incremental growing degree days (GDD), and NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) normalized difference vegetation index (NDVI) 8-day composite cumulative integral data. We obtain a specific location's daily minimum and maximum temperatures from the nearest National Oceanic and Atmospheric Administration (NOAA) weather stations posted on the National Climate Data Center (NCDC) Climate Data Online (CDO) archive and compute GDD. The date range for this study is January 1, 2000 through December 31, 2012. We employ a novel process, a repeating logistic product (RLP), to compensate for short-term weather variability and data drops from the recording stations and fit a curve to the median daily GDD values, adjusting for asymmetry, amplitude, and phase shift that minimize the sum of squared errors when comparing the observed and predicted GDD. The resulting curve, here referred to as the surrogate GDD, is the time-temperature phasing parameter used to convert Cartesian NDVI values into polar coordinate pairs, multiplying the NDVI values as the radial by the cosine and sine of the surrogate GDD as the angular. Depending on the vegetation type and the original NDVI curve, the polar NDVI curve may be nearly circular, kidney-shaped, or pear-shaped in the case of conifers, deciduous, or agriculture, respectively. We examine the points of tangency about the polar coordinate NDVI curve, identifying values of 1, 0, -1, or infinity, as each of these represent natural inflection points. Lines connecting the origin to each tangent point illustrate and quantify the parametrically segmentation of the growing season based on the GDD and NDVI ostensible dependency. Furthermore, the area contained by each segment represents the apparent vegetation production. A particular benefit is that the inflection points are determined near real-time, as MODIS NDVI, 8-day composite data become available, affording an effective forecasting and hindcasting tool.

  2. METHANOL TRANSESTERIFICATION OF DIFFERENT VEGETABLE OILS

    Directory of Open Access Journals (Sweden)

    Slavi Kunev Ivanov

    2007-06-01

    Full Text Available The result of the investigation on methyl esters obtained on the basis of used sunflower oil, rapeseed oil and soybean oil are given in this paper. Transesterification reaction conditions that affect yield and purity of the product esters including oil quality, type and concentration of catalyst, temperature and reaction time were examined. Methanol esterification of different oils at 60 0C with 1-10 % (v/v sodium met-oxide was studied. With appropriate percent of sodium met-oxide, temperature 60 0C and 1 hour, all investigated oils were sufficiently transesterified and could be used as fuel in diesel engines.

  3. Methane emissions in Danish riparian wetlands : Ecosystem comparison and pursuit of vegetation indexes as predictive tools

    DEFF Research Database (Denmark)

    Audet, Joachim; Johansen, Jan Ravn

    2013-01-01

    The present study was conducted to (i) investigate parameters influencing the fluxes of the greenhouse gas methane (CH4) in Danish riparian wetlands with contrasting vegetation characteristics and (ii) develop models relating CH4 emissions to soil and/or vegetation parameters integrating the spatial and temporal variability in the fluxes. Fluxes of CH4 were monitored in 12 wetland plots over a year using static chambers, yielding a dataset with more than 800 measured fluxes of CH4. Yearly emissions of CH4 ranged from ?0.2 to 38.3 g CH4-C m?2 year?1, and significant effects of groundwater level, soil temperature (10 cm depth), peat depth, sulfate, nitrate, and soil carbon content were found. Two methods based on easily available environmental parameters to estimate yearly CH4 emissions from riparian wetlands are presented. The first uses a generalized linear model (GLM) to predict yearly CH4 emissions based on the humidity preference of vegetation (Ellenberg-F), peat depth and degree of humification of the peat (von Post index). The second method relies solely on plant species composition and uses weighted-average regression and calibration to link the vegetation assemblage to yearly CH4 emission. Both models gave reliable predictions of the yearly CH4 fluxes in riparian wetlands (modeling efficiency > 0.35). Our findings support the use of vegetation, possibly in combination with some soil parameters such as peat depth, as indicator of CH4 emission in wetlands.

  4. Intra-sensor Spectral Compatibility Analysis of the Enhanced Vegetation Index for Moderate Resolution Imagers Using Hyperion

    Science.gov (United States)

    Miura, T.; Obata, K.; Huete, A. R.

    2013-12-01

    Spectral vegetation indices (VIs) are one of the more important satellite products for monitoring and characterizing seasonal dynamics and interannual variability of terrestrial vegetation in regional to global scales. The enhanced vegetation index (EVI), designed for the National Aeronautics and Space Administration (NASA) Earth Observing System (EOS) Moderate Resolution Imaging Spectroradiometer (MODIS) sensors, has been shown to effectively characterize global vegetation states and ecosystem processes, and encompass the range of biophysical/biochemical information in manners to complement the conventional, normalized difference vegetation index (NDVI). Because the EVI is limited to sensor systems designed with a blue band, a 2-band EVI, without a blue band, was recently developed (referred to as the EVI2), which has the best similarity with the 3-band EVI for the MODIS sensors, particularly when residual atmospheric effects are insignificant and data quality is good. In this study, we evaluated intra-sensor spectral compatibility between the EVI and EVI2 and their sensitivities to aerosol contaminations for select moderate resolution imaging sensors, including Visible/Infrared Imager/Radiometer Suite (VIIRS), MODIS, Second Generation Global Imager (S-GLI), and SPOT-4 VEGETATION, and for Landsat-7 Enhanced Thematic Mapper Plus (ETM+), using a global set of Earth Observing One (EO-1) Hyperion hyperspectral data. Hyperion scenes were spectrally aggregated into red, near-infrared (NIR), and blue bandpasses of the five sensors and spatially aggregated into 1 km resolution pixels. Two atmospheric correction scenarios were also applied to examine the impact of the atmosphere on intra-sensor EVI/EVI2 compatibility: (1) Rayleigh/ozone/water vapor (ROW)-corrected and (2) total-atmosphere-corrected 'top-of-canopy (TOC)' reflectances. The EVI of all the five sensor bandpasses exhibited great resistance to atmospheric aerosol contaminations. The EVI2 of every sensor was, on the other hand, impacted by the aerosol effects as it no longer possesses the aerosol resistance term. The EVI and EVI2 showed the best similarities for MODIS and ETM+ bands. Their similarities degraded for VIIRS bands and were the worst for VEGETATION and S-GLI bands for which EVI and EVI2 differences reached 0.04 EVI units. These results indicate that the EVI2 may require an adjustment or optimization for some sensor bandpasses in order to retain intra-sensor compatibility with the EVI.

  5. Normalized Difference Vegetation Index for Fanno Creek, Oregon

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Fanno Creek is a tributary to the Tualatin River and flows though parts of the southwest Portland metropolitan area. The stream is heavily influenced by urban...

  6. Camera derived vegetation greenness index as proxy for gross primary production in a low Arctic wetland area

    DEFF Research Database (Denmark)

    Westergaard-Nielsen, Andreas; Lund, Magnus

    2013-01-01

    The Arctic is experiencing disproportionate warming relative to the global average, and the Arctic ecosystems are as a result undergoing considerable changes. Continued monitoring of ecosystem productivity and phenology across temporal and spatial scales is a central part of assessing the magnitude of these changes. This study investigates the ability to use automatic digital camera images (DCIs) as proxy data for gross primary production (GPP) in a complex low Arctic wetland site. Vegetation greenness computed from DCIs was found to correlate significantly (R2 = 0.62, p < 0.001) with a normalized difference vegetation index (NDVI) product derived from the WorldView-2 satellite. An object-based classification based on a bi-temporal image composite was used to classify the study area into heath, copse, fen, and bedrock. Temporal evolution of vegetation greenness was evaluated and modeled with double sigmoid functions for each plant community. GPP at light saturation modeled from eddy covariance (EC) flux measurements were found to correlate significantly with vegetation greenness for all plant communities in the studied year (i.e., 2010), and the highest correlation was found between modeled fen greenness and GPP (R2 = 0.85, p < 0.001). Finally, greenness computed within modeled EC footprints were used to evaluate the influence of individual plant communities on the flux measurements. The study concludes that digital cameras may be used as a cost-effective proxy for potential GPP in remote Arctic regions.

  7. Assessment of RapidEye vegetation indices for estimation of leaf area index and biomass in corn and soybean crops

    Science.gov (United States)

    Kross, Angela; McNairn, Heather; Lapen, David; Sunohara, Mark; Champagne, Catherine

    2015-02-01

    Leaf area index (LAI) and biomass are important indicators of crop development and the availability of this information during the growing season can support farmer decision making processes. This study demonstrates the applicability of RapidEye multi-spectral data for estimation of LAI and biomass of two crop types (corn and soybean) with different canopy structure, leaf structure and photosynthetic pathways. The advantages of Rapid Eye in terms of increased temporal resolution (?daily), high spatial resolution (?5 m) and enhanced spectral information (includes red-edge band) are explored as an individual sensor and as part of a multi-sensor constellation. Seven vegetation indices based on combinations of reflectance in green, red, red-edge and near infrared bands were derived from RapidEye imagery between 2011 and 2013. LAI and biomass data were collected during the same period for calibration and validation of the relationships between vegetation indices and LAI and dry above-ground biomass. Most indices showed sensitivity to LAI from emergence to 8 m2/m2. The normalized difference vegetation index (NDVI), the red-edge NDVI and the green NDVI were insensitive to crop type and had coefficients of variations (CV) ranging between 19 and 27%; and coefficients of determination ranging between 86 and 88%. The NDVI performed best for the estimation of dry leaf biomass (CV = 27% and r2 = 090) and was also insensitive to crop type. The red-edge indices did not show any significant improvement in LAI and biomass estimation over traditional multispectral indices. Cumulative vegetation indices showed strong performance for estimation of total dry above-ground biomass, especially for corn (CV ? 20%). This study demonstrated that continuous crop LAI monitoring over time and space at the field level can be achieved using a combination of RapidEye, Landsat and SPOT data and sensor-dependant best-fit functions. This approach eliminates/reduces the need for reflectance resampling, VIs inter-calibration and spatial resampling.

  8. RNDSI: A ratio normalized difference soil index for remote sensing of urban/suburban environments

    Science.gov (United States)

    Deng, Yingbin; Wu, Changshan; Li, Miao; Chen, Renrong

    2015-07-01

    Understanding land use land cover change (LULCC) is a prerequisite for urban planning and environment management. For LULCC studies in urban/suburban environments, the abundance and spatial distributions of bare soil are essential due to its biophysically different properties when compared to anthropologic materials. Soil, however, is very difficult to be identified using remote sensing technologies majorly due to its complex physical and chemical compositions, as well as the lack of a direct relationship between soil abundance and its spectral signatures. This paper presents an empirical approach to enhance soil information through developing the ratio normalized difference soil index (RNDSI). The first step involves the generation of random samples of three major land cover types, namely soil, impervious surface areas (ISAs), and vegetation. With spectral signatures of these samples, a normalized difference soil index (NDSI) was proposed using the combination of bands 7 and 2 of Landsat Thematic Mapper Image. Finally, a ratio index was developed to further highlight soil covers through dividing the NDSI by the first component of tasseled cap transformation (TC1). Qualitative (e.g., frequency histogram and box charts) and quantitative analyses (e.g., spectral discrimination index and classification accuracy) were adopted to examine the performance of the developed RNDSI. Analyses of results and comparative analyses with two other relevant indices, biophysical composition index (BCI) and enhanced built-up and bareness Index (EBBI), indicate that RNDSI is promising in separating soil from ISAs and vegetation, and can serve as an input to LULCC models.

  9. The relationship between vegetation supply water index and forest resource of Bogd Khaan Mountain in the Mongolia

    Science.gov (United States)

    Naranmandah, Z.; Tuya, S.; Batbayar, J.

    2014-11-01

    Bogd Khan Mountain all areas consist of 41129 hectares from 22992 hectares 55.9 of the forest about 20 rivers originate from mountain. Therefore Tuul river recourse depends on the flow of these water resources. In this research paper for using Landsat-5 satellite estimation of forest resource of Bogd Khan Mountain. How depending of Tuul river watering resource. This area estimation of vegetation index soil, soil temperature, soil water supply is the index to how depends on each other. Result is relate of vegetation index and water supply index directly but soil temperature undirectly reciprocal value. There for forest area, soil to low and it's possible to accumulate moisture.

  10. Estimation of the soil heat flux/net radiation ratio based on spectral vegetation indexes in high-latitude Arctic areas

    International Nuclear Information System (INIS)

    The vegetation communities in the Arctic environment are very sensitive to even minor climatic variations and therefore the estimation of surface energy fluxes from high-latitude vegetated areas is an important subject to be pursued. This study was carried out in July-August and used micro meteorological data, spectral reflectance signatures, and vegetation biomass to establish the relation between the soil heat flux/net radiation (G / Rn) ratio and spectral vegetation indices (SVIs). Continuous measurements of soil temperature and soil heat flux were used to calculate the surface ground heat flux by use of conventional methods, and the relation to surface temperature was investigated. Twenty-seven locations were established, and six samples per location, including the measurement of the surface temperature and net radiation to establish the G/Rn ratio and simultaneous spectral reflectance signatures and wet biomass estimates, were registered. To obtain regional reliability, the locations were chosen in order to represent the different Arctic vegetation communities in the study area; ranging from dry tundra vegetation communities (fell fields and dry dwarf scrubs) to moist/wet tundra vegetation communities (snowbeds, grasslands and fens). Spectral vegetation indices, including the simple ratio vegetation index (RVI) and the normalized difference vegetation index (NDVI), were calculated. A comparison of SVIs to biomass proved that RVI gave the best linear expression, and NDVI the best exponential expression. A comparison of SVIs and the surface energy flux ratio G / Rn proved that NDVI gave the best linear expression. SPOT HRV images from July 1989 and 1992 were used to map NDVI and G / Rn at a regional scale. (author)

  11. A comparison of two different approaches for mapping potential ozone damage to vegetation. A model study

    International Nuclear Information System (INIS)

    Two very different types of approaches are currently in use today for indicating risk of ozone damage to vegetation in Europe. One approach is the so-called AOTX (accumulated exposure over threshold of X ppb) index, which is based upon ozone concentrations only. The second type of approach entails an estimate of the amount of ozone entering via the stomates of vegetation, the AFstY approach (accumulated stomatal flux over threshold of Y nmol m-2 s-1). The EMEP chemical transport model is used to map these different indicators of ozone damage across Europe, for two illustrative vegetation types, wheat and beech forests. The results show that exceedences of critical levels for either type of indicator are widespread, but that the indicators give very different spatial patterns across Europe. Model simulations for year 2020 scenarios suggest reductions in risks of vegetation damage whichever indicator is used, but suggest that AOT40 is much more sensitive to emission control than AFstY values. - Model calculations of AOT40 and AFstY show very different spatial variations in the risks of ozone damage to vegetation

  12. Estimation of vegetation parameters such as Leaf Area Index from polarimetric SAR data

    Science.gov (United States)

    Hetz, Marina; Blumberg, Dan G.; Rotman, Stanley R.

    2010-05-01

    This work presents the analysis of the capability to use the radar backscatter coefficient in semi-arid zones to estimate the vegetation crown in terms of Leaf Area Index (LAI). The research area is characterized by the presence of a pine forest with shrubs as an underlying vegetation layer (understory), olive trees, natural grove areas and eucalyptus trees. The research area was imaged by an airborne RADAR system in L-band during February 2009. The imagery includes multi-look radar images. All the images were fully polarized i.e., HH, VV, HV polarizations. For this research we used the central azimuth angle (113° ). We measured LAI using the ?T Sun Scan Canopy Analysis System. Verification was done by analytic calculations and digital methods for the leaf's and needle's surface area. In addition, we estimated the radar extinction coefficient of the vegetation volume by comparing point calibration targets (trihedral corner reflectors with 150cm side length) within and without the canopy. The radar extinction in co- polarized images was ~26dB and ~24dB for pines and olives respectively, compared to the same calibration target outside the vegetation. We used smaller trihedral corner reflectors (41cm side length) and covered them with vegetation to measure the correlation between vegetation density, LAI and radar backscatter coefficient for pines and olives under known conditions. An inverse correlation between the radar backscatter coefficient of the trihedral corner reflectors covered by olive branches and the LAI of those branches was observed. The correlation between LAI and the optical transmittance was derived using the Beer-Lambert law. In addition, comparing this law's principle to the principle of the radar backscatter coefficient production, we derived the equation that connects between the radar backscatter coefficient and LAI. After extracting the radar backscatter coefficient of forested areas, all the vegetation parameters were used as inputs for the MIMICS model that simulates the radar backscatter coefficient of pines. The model results show a backscatter of -18dB in HV polarization which is 13dB higher than the mean pines backscatter in the radar images, whereas the co-polarized images revealed a backscatter of -10dB which is 23dB higher than the actual backscatter value deriver from the radar images. Therefore, next step in the research will incorporate other vegetation parameters and attempt to understand the discrepancies between the simulation and the actual data.

  13. Predicting gender differences in liking for vegetables and preference for a variety of vegetables among 11-year-old children.

    Science.gov (United States)

    Lehto, Elviira; Ray, Carola; Haukkala, Ari; Yngve, Agneta; Thorsdottir, Inga; Roos, Eva

    2015-12-01

    We studied the factors that predict liking for vegetables and preference for a variety of vegetables among schoolchildren. Additionally, we examined if there were gender differences in the predictors that explain the hypothesized higher scores in liking vegetables and preferences among girls. The data from the PRO GREENS project included 424 Finnish children (response rate 77%) aged 11 to 12. The children completed validated measures about social and environmental factors related to their liking for vegetables and preferences both at baseline 2009 and follow-up 2010. The associations were examined with regression and mediation analyses. The strongest predictors of both girls' and boys' liking and preferences were higher levels of eating vegetables together with the family, previous vegetable intake and a lower level of perceived barriers. Liking was additionally predicted by a lower level of parental demand that their child should eat vegetables. Girls reported higher levels of liking and preferences in the follow-up. This gender difference was mainly explained by girls' lower level of perceived barriers related to vegetable intake and girls' higher previous vegetable intake. Interventions that aim to increase the low vegetable intake among boys by increasing their liking for vegetables and preference for a variety of vegetables could benefit from targeting perceived barriers, namely boys' perception and values concerning the consumption of vegetables. PMID:26206174

  14. Assessing Land Degradation and Desertification Using Vegetation Index Data: Current Frameworks and Future Directions

    Directory of Open Access Journals (Sweden)

    Thomas P. Higginbottom

    2014-10-01

    Full Text Available Land degradation and desertification has been ranked as a major environmental and social issue for the coming decades. Thus, the observation and early detection of degradation is a primary objective for a number of scientific and policy organisations, with remote sensing methods being a candidate choice for the development of monitoring systems. This paper reviews the statistical and ecological frameworks of assessing land degradation and desertification using vegetation index data. The development of multi-temporal analysis as a desertification assessment technique is reviewed, with a focus on how current practice has been shaped by controversy and dispute within the literature. The statistical techniques commonly employed are examined from both a statistical as well as ecological point of view, and recommendations are made for future research directions. The scientific requirements for degradation and desertification monitoring systems identified here are: (I the validation of methodologies in a robust and comparable manner; and (II the detection of degradation at minor intensities and magnitudes. It is also established that the multi-temporal analysis of vegetation index data can provide a sophisticated measure of ecosystem health and variation, and that, over the last 30 years, considerable progress has been made in the respective research.

  15. Agricultural Drought Pattern in West Java Using Thermal Vegetation Index from Modis-Terra Satellite

    Directory of Open Access Journals (Sweden)

    Sri Hardiyanti Purwadhi

    2013-04-01

    Full Text Available This study examines agricultural drought paddy fields in West Java. The aims of this research are to know the pattern and distribution of paddy field drought in West Java and the correlation between drought and the physical characteristics. The agricultural drought is obtained from TVI (Thermal Vegetation Index model. TVI is derived from MODIS Terra satellite image, which is the ratio between the LST (Land Surface Temperature and EVI (Enhanced Vegetation Index. Physical factors studied are rainfall, l slope, geomorphology, soil drainage, and irrigation areas. The most severe drought occurred in September 2006 because of El Nino, covering 806,564 ha, and distributed in almost all West Java Province while the lowest occurred in September 2010 because of La Nina, covering 101,959 ha, and mostly distributed in Subang and Indramayu district. Spatial distribution of drought in 2000-2011 has the same pattern. At the start of the dry season (May drought occurred in the north (along the coast then expanded to the east / south in the middle of the dry season (July-August and then increased further to the west at the end of the dry season (September. Incidence of drought has correlation with the physical condition of the area, but the most influential is the rainfall based on Chi-square test.

  16. Use of Radar Vegetation Index (RVI) in Passive Microwave Algorithms for Soil Moisture Estimates

    Science.gov (United States)

    Rowlandson, T. L.; Berg, A. A.

    2013-12-01

    The Soil Moisture Active Passive (SMAP) satellite will provide a unique opportunity for the estimation of soil moisture by having simultaneous radar and radiometer measurements available. As with the Soil Moisture and Ocean Salinity (SMOS) satellite, the soil moisture algorithms will need to account for the contribution of vegetation to the brightness temperature. Global maps of vegetation volumetric water content (VWC) are difficult to obtain, and the SMOS mission has opted to estimate the optical depth of standing vegetation by using a relationship between the VWC and the leaf area index (LAI). LAI is estimated from optical remote sensing or through soil-vegetation-atmosphere transfer modeling. During the growing season, the VWC of agricultural crops can increase rapidly, and if cloud cover exists during an optical acquisition, the estimation of LAI may be delayed, resulting in an underestimation of the VWC and overestimation of the soil moisture. Alternatively, the radar vegetation index (RVI) has shown strong correlation and linear relationship with VWC for rice and soybeans. Using the SMAP radar to produce RVI values that are coincident to brightness temperature measurements may eliminate the need for LAI estimates. The SMAP Validation Experiment 2012 (SMAPVEX12) was a cal/val campaign for the SMAP mission held in Manitoba, Canada, during a 6-week period in June and July, 2012. During this campaign, soil moisture measurements were obtained for 55 fields with varying soil texture and vegetation cover. Vegetation was sampled from each field weekly to determine the VWC. Soil moisture measurements were taken coincident to overpasses by an aircraft carrying the Passive and Active L-band System (PALS) instrumentation. The aircraft flew flight lines at both high and low altitudes. The low altitude flight lines provided a footprint size approximately equivalent to the size of the SMAPVEX12 field sites. Of the 55 field sites, the low altitude flight lines provided measurements for 15 fields. One field was planted in corn; three were pasture; six were soybeans; three were wheat; and two were winter wheat. The average RVI for each field was determined for each PALS overpass, with sampled radar data confined to the field dimensions. A linear interpolation was conducted between measured values of VWC to estimate a daily VWC value. A linear regression was conducted between the average VWC and the RVI, for each vegetation type. A positive linear relationship was found for all crops, with the exception of pasture. The correlation between the RVI and VWC was strong for corn and pasture, but moderate for soybeans and winter wheat; however, the correlation for corn was not significant. The developed models were utilized to provide a calculated VWC which was inputted into a modified version of the Land Parameter Retrieval Model (LPRM) to determine the error associated with using a calculated VWC from the RVI versus measured VWC data. The LPRM outputs for both scenarios were compared to the PALS radiometer measurements of brightness temperature.

  17. Detecting post-fire burn severity and vegetation recovery using multitemporal remote sensing spectral indices and field-collected composite burn index data in a ponderosa pine forest

    Science.gov (United States)

    Chen, X.; Vogelmann, J.E.; Rollins, M.; Ohlen, D.; Key, C.H.; Yang, L.; Huang, C.; Shi, H.

    2011-01-01

    It is challenging to detect burn severity and vegetation recovery because of the relatively long time period required to capture the ecosystem characteristics. Multitemporal remote sensing data can providemultitemporal observations before, during and after a wildfire, and can improve the change detection accuracy. The goal of this study is to examine the correlations between multitemporal spectral indices and field-observed burn severity, and to provide a practical method to estimate burn severity and vegetation recovery. The study site is the Jasper Fire area in the Black Hills National Forest, South Dakota, that burned during August and September 2000. Six multitemporal Landsat images acquired from 2000 (pre-fire), 2001 (post-fire), 2002, 2003, 2005 and 2007 were used to assess burn severity. The normalized difference vegetation index (NDVI), enhanced vegetation index (EVI), normalized burn ratio (NBR), integrated forest index (IFI) and the differences of these indices between the pre-fire and post-fire years were computed and analysed with 66 field-based composite burn index (CBI) plots collected in 2002. Results showed that differences of NDVI and differences of EVI between the pre-fire year and the first two years post-fire were highly correlated with the CBI scores. The correlations were low beyond the second year post-fire. Differences of NBR had good correlation with CBI scores in all study years. Differences of IFI had low correlation with CBI in the first year post-fire and had good correlation in later years. A CBI map of the burnt area was produced using regression tree models and the multitemporal images. The dynamics of four spectral indices from 2000 to 2007 indicated that both NBR and IFI are valuable for monitoring long-term vegetation recovery. The high burn severity areas had a much slower recovery than the moderate and low burn areas. ?? 2011 Taylor & Francis.

  18. Inter-Comparison of ASTER and MODIS Surface Reflectance and Vegetation Index Products for Synergistic Applications to Natural Resource Monitoring

    Directory of Open Access Journals (Sweden)

    Hirokazu Yamamoto

    2008-04-01

    Full Text Available Synergistic applications of multi-resolution satellite data have been of a great interest among user communities for the development of an improved and more effective operational monitoring system of natural resources, including vegetation and soil. In this study, we conducted an inter-comparison of two remote sensing products, namely, visible/near-infrared surface reflectances and spectral vegetation indices (VIs, from the high resolution Advanced Thermal Emission and Reflection Radiometer (ASTER (15 m and lower resolution Moderate Resolution Imaging Spectroradiometer (MODIS (250 m – 500 m sensors onboard the Terra platform. Our analysis was aimed at understanding the degree of radiometric compatibility between the two sensors’ products due to sensor spectral bandpasses and product generation algorithms. Multiple pairs of ASTER and MODIS standard surface reflectance products were obtained at randomly-selected, globally-distributed locations, from which two types of VIs were computed: the normalized difference vegetation index and the enhanced vegetation indices with and without a blue band. Our results showed that these surface reflectance products and the derived VIs compared well between the two sensors at a global scale, but subject to systematic differences, of which magnitudes varied among scene pairs. An independent assessment of the accuracy of ASTER and MODIS standard products, in which “in-house” surface reflectances were obtained using in situ Aeronet atmospheric data for comparison, suggested that the performance of the ASTER atmospheric correction algorithm may be variable, reducing overall quality of its standard reflectance product. Atmospheric aerosols, which were not corrected for in the ASTER algorithm, were found not to impact the quality of the derived reflectances. Further investigation is needed to identify the sources of inconsistent atmospheric correction results associated with the ASTER algorithm, including additional quality assessments of the ASTER and MODIS products with other atmospheric radiative transfer codes.

  19. Variação do Índice de Vegetação por Diferença Normalizada na lagoa Itapeva, litoral norte do Rio Grande do Sul, Brasil, a partir de análise de séries temporais / Variations of the Normalized Difference Vegetation Index (NDVI) in the Itapeva-RS lake, north coast of Rio Grande do Sul, Brazil, from temporal series analysis

    Scientific Electronic Library Online (English)

    Juliane Beatriz, Lissner; Laurindo Antonio, Guasselli.

    2013-08-01

    Full Text Available O objetivo do trabalho foi analisar os padrões de comportamento espaço-temporal dos valores do Índice de Vegetação por Diferença Normalizada (NDVI) na lagoa Itapeva-RS, por meio de imagens Landsat TM5 e ETM+7, compreendendo o período de 1985 a 2010. Para a análise do comportamento espaço-temporal fo [...] ram utilizadas classes de Índice de Vegetação por Diferença Normalizada (NDVI) e Análise por Séries Temporais (TSA) de imagens. Para validação dos padrões observados foram coletadas amostras de água em seis pontos na lagoa Itapeva para clorofila_a, Totais de Sólidos Suspensos e transparência do disco Secchi. Estes resultados foram correlacionados com os valores de NDVI. Os mapas de classes de NDVI gerados após a análise da TSA evidenciaram padrões de dinâmica espaciais e sazonais associados as variáveis ambientais atuantes, permitindo o estabelecimento de três grandes compartimentos para a lagoa Itapeva: norte, centro e sul. A análise da série temporal de imagens mostra que o aumento e o decréscimo dos valores de NDVI estão associados aos períodos de floração do fitoplâncton. Concluiu-se que a análise da Série Temporal de imagens Landsat foi satisfatória no que se refere ao comportamento espaço-temporal da variação das classes de NDVI. Abstract in english The objective of this study was to analyze the pattern spatial-temporal values of the Normalized Difference Vegetation Index (NDVI) in Itapeva-RS lake, using Landsat TM5 and ETM + 7 images, from 1985 through 2010. For the analysis of space-temporal behavior classes was used Normalized Difference Veg [...] etation Index (NDVI) classes and Temporal Series Analysis (TSA). To validate the observed patterns were collected water samples from six points in the Itapeva Lake for clorofila_a, Total suspended solids and Secchi disk transparency. These results were correlated with NDVI values. The NDVI classes maps generated after analysis of TSA, showed dynamic patterns of seasonal and spatial associated with environmental variables that were actuating, allowing the establishment of three distinctive surfaces in Itapeva Lake: north, center and south. The Temporal Series Analysis of images shows that the increase and decrease of NDVI values are associated with periods of phytoplankton bloom. One concluded that the Temporal Series Analysis of Landsat images was satisfactory with regard to the behavior of spatial and temporal variation of NDVI classes.

  20. Soil microbial properties under different vegetation types on Mountain Han.

    Science.gov (United States)

    Wang, Miao; Qu, Laiye; Ma, Keming; Yuan, Xiu

    2013-06-01

    This study investigated the influence of broadleaf and conifer vegetation on soil microbial communities in a distinct vertical distribution belt in Northeast China. Soil samples were taken at 0-5, 5-10 and 10-20 cm depths from four vegetation types at different altitudes, which were characterized by poplar (Populus davidiana) (1250-1300 m), poplar (P. davidiana) mixed with birch (Betula platyphylla) (1370-1550 m), birch (B. platyphylla) (1550-1720 m), and larch (Larix principis-rupprechtii) (1840-1890 m). Microbial biomass and community structure were determined using the fumigation-extraction method and phospholipid fatty acid (PLFA) analysis, and soil fungal community level physiological profiles (CLPP) were characterized using Biolog FF Microplates. It was found that soil properties, especially soil organic carbon and water content, contributed significantly to the variations in soil microbes. With increasing soil depth, the soil microbial biomass, fungal biomass, and fungal catabolic ability diminished; however, the ratio of fungi to bacteria increased. The fungal ratio was higher under larch forests compared to that under poplar, birch, and their mixed forests, although the soil microbial biomass was lower. The direct contribution of vegetation types to the soil microbial community variation was 12%. If the indirect contribution through soil organic carbon was included, variations in the vegetation type had substantial influences on soil microbial composition and diversity. PMID:23737003

  1. [Comparison of GIMMS and MODIS normalized vegetation index composite data for Qing-Hai-Tibet Plateau].

    Science.gov (United States)

    Du, Jia-Qiang; Shu, Jian-Min; Wang, Yue-Hui; Li, Ying-Chang; Zhang, Lin-Bo; Guo, Yang

    2014-02-01

    Consistent NDVI time series are basic and prerequisite in long-term monitoring of land surface properties. Advanced very high resolution radiometer (AVHRR) measurements provide the longest records of continuous global satellite measurements sensitive to live green vegetation, and moderate resolution imaging spectroradiometer (MODIS) is more recent typical with high spatial and temporal resolution. Understanding the relationship between the AVHRR-derived NDVI and MODIS NDVI is critical to continued long-term monitoring of ecological resources. NDVI time series acquired by the global inventory modeling and mapping studies (GIMMS) and Terra MODIS were compared over the same time periods from 2000 to 2006 at four scales of Qinghai-Tibet Plateau (whole region, sub-region, biome and pixel) to assess the level of agreement in terms of absolute values and dynamic change by independently assessing the performance of GIMMS and MODIS NDVI and using 495 Landsat samples of 20 km x20 km covering major land cover type. High correlations existed between the two datasets at the four scales, indicating their mostly equal capability of capturing seasonal and monthly phenological variations (mostly at 0. 001 significance level). Simi- larities of the two datasets differed significantly among different vegetation types. The relative low correlation coefficients and large difference of NDVI value between the two datasets were found among dense vegetation types including broadleaf forest and needleleaf forest, yet the correlations were strong and the deviations were small in more homogeneous vegetation types, such as meadow, steppe and crop. 82% of study area was characterized by strong consistency between GIMMS and MODIS NDVI at pixel scale. In the Landsat NDVI vs. GIMMS and MODIS NDVI comparison of absolute values, the MODIS NDVI performed slightly better than GIMMS NDVI, whereas in the comparison of temporal change values, the GIMMS data set performed best. Similar with comparison results of GIMMS and MODIS NDVI, the consistency across the three datasets was clearly different among various vegetation types. In dynamic changes, differences between Landsat and MODIS NDVI were smaller than Landsat NDVI vs. GIMMS NDVI for forest, but Landsat and GIMMS NDVI agreed better for grass and crop. The results suggested that spatial patterns and dynamic trends of GIMMS NDVI were found to be in overall acceptable agreement with MODIS NDVI. It might be feasible to successfully integrate historical GIMMS and more recent MODIS NDVI to provide continuity of NDVI products. The accuracy of merging AVHRR historical data recorded with more modern MODIS NDVI data strongly depends on vegetation type, season and phenological period, and spatial scale. The integration of the two datasets for needleleaf forest, broadleaf forest, and for all vegetation types in the phenological transition periods in spring and autumn should be treated with caution. PMID:24830255

  2. Enhanced Vegetation Index (EVI na análise da dinâmica da vegetação da reserva biológica de Sooretama, ES Use of Enhanced Vegetation Index (EVI in the analysis os vegetation dynamics of the Sooretama biological reservation, ES

    Directory of Open Access Journals (Sweden)

    André Quintão de Almeida

    2008-12-01

    Full Text Available Técnicas de análises de séries temporais são utilizadas para caracterizar o comportamento de fenômenos naturais no domínio do tempo. Neste artigo, segundo a metodologia proposta por Box et al. (1994, 125 observações do Enhanced Vegetation Index (EVI foram analisadas. Os valores modelados correspondem às variações temporais ocorridas no dossel florestal da reserva biológica de Sooretama, localizada ao Norte do Estado do Espírito Santo, no Município de Linhares. Os resultados indicaram que a metodologia foi adequada. Os resíduos do modelo ajustado são não correlacionados com distribuição normal, média zero e variância s². Com o menor valor do Critério de Informação de Akaike (AIC -570,51, o modelo ajustado foi o Sazonal Auto-Regressivo Integrado de Médias Móveis (1,0,1(1,0,112.Temporal series analysis techniques are used to characterize the behavior of natural phenomenon in time domain. In this paper, 125 Enhanced Vegetation Index (EVI observations were analyzed according to the methodology proposed by Box et al.(1994. The values modeled correspond to the temporal variations that occurred in the forest canopy of the Sooretama Biological Reserve, in northern Espírito Santo, in the district of Linhares. The results indicated that such methodology was adequate. The residues of the adjusted model are not correlated with normal distribution, zero average and s² variance. At the lowest value of the Akaike Information Criteria (AIC -570. 51, the model adjusted was the Mobile Average Integrated Self-Regressive Seasonal model (1, 0, 1 (1, 0, 1-12.

  3. Lipid Peroxidation in Rat Liver using Different Vegetable Oils

    International Nuclear Information System (INIS)

    The objective of the study was to evaluate the effect of different vegetable oils (Red Palm Olien (RPO), Palm Olein (PO), Corn Oil (CO) and Coconut Oil on lipid peroxidation of rat liver. One hundred and thirty two Sprague Dawley male rats were randomly divided into two groups. The first group contains seventy two rats were divided into twelve groups of 6 rats per group and were treated with different concentrations of RPO (5 %, 10 % and 15 %) for 2, 4 and 8 weeks. The second group contains sixty male rats were randomly divided into ten groups of 6 rats per group and were treated with 15 % of RPO, PO, CO and COC for 4 and 8 weeks. The results shows that after 8 weeks of treatment the malonaldehyde (MDA) value in RPO group was significantly lower (P≤0.05) than control or vegetable oils studied. These experiments suggested that red palm olein antioxidants present in rat diets may better attenuate peroxyl radical than other vegetable oil studied. (author)

  4. Chlorophyll content mapping of urban vegetation in the city of Valencia based on the hyperspectral NAOC index

    OpenAIRE

    Delegido, Jes??s; Van Wittenberghe, Shari; Verrelst, Jochem; Ortiz, Violeta; Veroustraete, Frank; Valcke, Roland; Samson, Roeland; Rivera, Juan P.; Tenjo, Carolina; Moreno, Jos??

    2014-01-01

    Spatially distributed chlorophyll content of urban vegetation provides an important indicator of a plant's health status, which might depend on the habitat quality of the specific urban environment. Recent advances in optical remote sensing led to improved methodologies to monitor vegetation properties. The hyperspectral index NAOC (Normalized Area Over reflectance Curve) is one of these new tools that can be used for mapping chlorophyll content. In this paper we present the work done to quan...

  5. Avaliação dos índices de vegetação NDVI, SR e TVI na discriminação de fitofisionomias dos ambientes do Pantanal de Cáceres/MT / Evaluation of vegetation indexes NDVI, SR and TVI in the discrimination of vegetation types of environments of 'Pantanal' in Cáceres, Mato Grosso State

    Scientific Electronic Library Online (English)

    Edinéia Aparecida dos Santos, Galvanin; Sandra Mara Alves da Silva, Neves; Carla Bernadete Madureira, Cruz; Ronaldo José, Neves; Paulo Henrique Hack de, Jesus; Jesã Pereira, Kreitlow.

    2014-09-01

    Full Text Available Este artigo faz uma comparação dos índices de vegetação Normalized Difference Vegetation Index (NDVI), Simple Ratio (SR) e Transformed Vegetation Index (TVI), na discriminação das fitofisionomias de três ambientes do Pantanal de Cáceres, Mato Grosso, considerando a sazonalidade (períodos seco e úmid [...] o). As imagens utilizadas foram as do satélite Landsat TM 5, do ano de 2009 (período seco) e de 2010 (período úmido). As análises mostraram que o NDVI apresentou melhor desempenho em relação ao SR e TVI para os diferentes ambientes. Abstract in english This paper compares the performance of some vegetation indexes: Normalized Difference Vegetation Index (NDVI), Simple Ratio (SR) e Transformed Vegetation Index (TVI), applied in seasonal periods to verify which one best fits to discriminate the vegetation types of environments of 'Pantanal' in Cácer [...] es, Mato Grosso state, Brazil, in Landsat TM 5 image of 2009 in the dry period and 2010 in the humid period. Result verification of indexes images showed that NDVI provide a better performance than the SR and TVI indexes for different environments.

  6. Long-term vegetation monitoring for different habitats in floodplains

    Directory of Open Access Journals (Sweden)

    LANG Petra

    2014-03-01

    Full Text Available A floodplain-restoration project along the Danube between Neuburg and Ingolstadt (Germany aims to bring back water and sediment dynamic to the floodplain. The accompanied long-term monitoring has to document the changes in biodiversity related to this new dynamics. Considerations on and results of the vegetation monitoring concept are documented in this paper. In a habitat rich ecosystem like a floodplain different habitats (alluvial forest, semi-aquatic/aquatic sites have different demands on the sampling methods. Therefore, different monitoring designs (preferential, random, systematic, stratified random and transect sampling are discussed and tested for their use in different habitat types of the floodplain. A stratified random sampling is chosen for the alluvial forest stands, as it guarantees an equal distribution of the monitoring plots along the main driving factors, i.e. influence of water. The parameters distance to barrage, ecological flooding, height above thalweg and distance to the new floodplain river are used for stratifying and the plots are placed randomly into these strata, resulting in 117 permanent plots. Due to small changes at the semi-aquatic/aquatic sites a transect sampling was chosen. Further, a rough stratification (channel bed, river bank adjacent floodplain was implemented, which was only possible after the start of the restoration project. To capture the small-scale changes due to the restoration measures on the vegetation, 99 additional plots completed the transect sampling. We conclude that hetereogenous study areas need different monitoring approaches, but, later on, a joint analysis must be possible.

  7. Vegetation Response and Streamflow Anomalies: Exploring the Modulating Effect of Watershed Storage as Estimated by a Regionalized Stream Recession Index

    Science.gov (United States)

    Worland, S. C.; Bennartz, R.; Murphy, J.; Merrick, T.; Bradley, M.; Hornberger, G. M.

    2014-12-01

    Water managers often make water allocation decisions based on data that is integrated at regional scales much coarser than those at which water management decisions are typically made. Important sub-regional variations in the data are subsumed in the aggregate, potentially leading to an improper handling of water resources. A combination of stream discharge characteristics and remotely sensed data can provide information that is responsive at local scales, such as watershed vulnerability to anomalous moisture conditions. We conducted an exploratory analysis of Normalized Difference Vegetation Index (NDVI) data (500 m2 resolution, 16 day) obtained from NASA's Moderate Resolution Imaging Spectroradiometer and USGS stream discharge (Q) records from over 100 unregulated streams in Tennessee for the years 2001-2012. The data sets were compiled to evaluate the vegetation response during a historical drought (Aug/Sept of 2007) within different streamflow recession index (SRI) regions. SRI can be applied as a metric for watershed storage and the ability of underlying aquifers to sustain streamflow through prolonged dry periods. The time series were filtered to remove seasonal trends, and bimonthly anomalies were calculated. Each of the three NDVI and Q time series (raw, filtered, and anomaly) were analyzed using cross-correlation analysis, cross-wavelet, and wavelet coherence analyses. Four SRI regions with similar land cover were chosen to spatially analyze NDVI anomalies during drought. The results from the cross-correlation analysis reveal strong biannual and annual correlations between raw NDVI and raw discharge values. Correlations between NDVI anomalies and discharge anomalies peak at lag periods of 1 to 1.5 months with NDVI leading. The wavelet coherence analysis suggests that drought dampens the monthly signal correlation between the raw values, and potentially removes a strong 2 year correlation between the anomalies. The spatial analysis shows regions with a higher SRI value tend to have higher NDVI values throughout a drought.

  8. Phytomass mapping of the "seridó caatinga" vegetation by the plant area and the normalized difference vegetation indeces

    Directory of Open Access Journals (Sweden)

    Costa Thomaz Corrêa e Castro da

    2002-01-01

    Full Text Available Phytomass is a critical information for economic and environmental activities like the establishment of policies for timber resources, forest management, studies of plant nutrient cycling, CO2 sink, among other. The phytomass of a Caatinga area was obtained by an empirical method using normalized difference vegetation index (NDVI of Landsat images, the plant area index (PAI and the phytomass inventory. At a first stage, linear, logarithmic and non-linear models were developed and tested. Bush and tree specimens were considered in the study, so that most of the individuals that contribute to the spectral answer detected by satellite images were included. At a second stage, the orbital parameter NDVI was used to map the PAI, which was used to map the phytomass, based on the relationship of this phytomass as a function of PAI. The residues between measurements and estimates based on NDVI varied from 0 to 84%, while the residues of total dry weight of phytomass per ha obtained by mapping and by dendrometrical equations varied from 5 to 104%, with a large trend of 166 and 448% in open Caatinga areas, due to the contribution of the herbaceous stratum to NDVI.

  9. Optimización del índice espectral de la vegetación NDVIcp / Optimization of the spectral vegetation index NDVIcp

    Scientific Electronic Library Online (English)

    Fernando, Paz-Pellat; Martín, Bolaños-González; Enrique, Palacios-Vélez; Luís A., Palacios-Sánchez; Mario, Martínez-Menes; Alfredo, Huete.

    2008-12-01

    Full Text Available La optimización de los índices espectrales de la vegetación para reducir el efecto del suelo y de la atmósfera, requiere hipótesis fuertes cuando no hay conocimiento relacionado con las variables atmosféricas y sólo información contenida en las imágenes satelitales. La optimización del índice NDVIcp [...] , diseñado para minimizar el efecto del suelo, es analizada con una perspectiva de su factibilidad y de las restricciones asociadas a este objetivo. Para explicar la problemática de la optimización del índice espectral de la vegetación NDVIcp, se analizó la estructura matemática de los efectos atmosféricos y se formuló el NDVIcp en función de esta estructura para analizar el problema de minimización de los efectos conjuntos del suelo y de la atmósfera. Los análisis mostraron que sin el conocimiento del tipo de aerosol (espesor óptico de la atmósfera) y modelo atmosférico, los intentos de reducción o eliminación de los efectos atmosféricos son indeterminados (implican soluciones múltiples al problema). Si se conocen la atmósfera y el aerosol, pero no el espesor óptico atmosférico, es posible minimizar los efectos atmosféricos y del suelo usando un esquema de aproximación de las constantes del índice NDVIcp al caso sin atmósfera. Abstract in english The optimization of the spectral vegetation indices to reduce the effects of soil and atmosphere, requires strong hypotheses when there is no knowledge related to the atmospheric variables and only information contained in the satellite images. The optimization of the index NDVIcp, designed to minim [...] ize the effect of soil, is analyzed under a perspective of its viability and of the restrictions associated with this objective. To explain the problematic of the optimization of the spectral vegetation index NDVIcp, an analysis was made of the mathematical structure of the atmospheric effects, and the NDVIcp was formulated as a function of this structure to analyze the problem of minimization of the joint effects of soil and of the atmosphere. The analyses showed that without the knowledge of the type of aerosol (optical thickness of the atmosphere) and atmospheric model, the attempts at reduction or elimination of the atmospheric effects are indetermined (imply multiple solutions to the problem). If the atmosphere and aerosol are known, but not the atmospheric optical thickness, it is possible to minimize the atmospheric effects and of the soil using a scheme of approximation of the constants of the NDVIcp index to the case without atmosphere.

  10. Differences in the deposition of radionuclides to leafy vegetables

    International Nuclear Information System (INIS)

    To quantify the variability in deposition to several species, the dry deposition of gaseous elemental radio-iodine and particulate radio-caesium on mature leafy vegetables was studied inside a deposition chamber by comparative experiments. The simultaneous exposition of endive, head lettuce, red oak leaf lettuce, curly kale, white cabbage and spinach was performed under homogeneous and controlled conditions (131 vertical stroke 2-portion, particle median, stomata opening, air humidity and temperature). Significant differences were observed for the 131 vertical stroke deposition on spring vegetables: the deposition on spinach was roughly 3times that on leaf lettuce, 4times that on endive and 9times that on head lettuce. For 134Cs, there was no significant difference between spinach and leaf lettuce, about twice the amount was deposited on both species as on endive and 3times as on head lettuce. All summer vegetables showed differences in deposition. For Iodine, the deposition on spinach was roughly 3times (6times) that on curly kale and 35times (100times) that on white cabbage in the 2 experiments. For Caesium, the deposition to curly kale was highest, about twice that on spinach and 35times (80times) that on white cabbage. The deposition was always the lowest on the closed heads of white cabbage and head lettuce. The many open stomata of spinach increased the efficiency of gaseous deposition. In addition, rough and crimpy leafs increased the particle deposition efficiency. The estimation of the deposition velocity showed that dry deposition was in average about 8times higher for 131 vertical stroke than for 134Cs. The influence of the particle size on the deposition velocity was small in the considered size range. Washing could reduce the contamination by about 10% for 131 vertical stroke and 45% for 134Cs. (orig.)

  11. Modelling spatial and temporal vegetation variability with the Climate Constrained Vegetation Index: evidence of CO2 fertilisation and of water stress in continental interiors

    Directory of Open Access Journals (Sweden)

    S. O. Los

    2015-06-01

    Full Text Available A model was developed to simulate spatial, seasonal and interannual variations in vegetation in response to temperature, precipitation and atmospheric CO2 concentrations; the model addresses shortcomings in current implementations. The model uses the minimum of 12 temperature and precipitation constraint functions to simulate NDVI. Functions vary based on the Köppen–Trewartha climate classification to take adaptations of vegetation to climate into account. The simulated NDVI, referred to as the climate constrained vegetation index (CCVI, captured the spatial variability (0.82 r r = 0.83 and interannual variability (median global r = 0.24 in NDVI. The CCVI simulated the effects of adverse climate on vegetation during the 1984 drought in the Sahel and during dust bowls of the 1930s and 1950s in the Great Plains in North America. A global CO2 fertilisation effect was found in NDVI data, similar in magnitude to that of earlier estimates (8 % for the 20th century. This effect increased linearly with simple ratio, a transformation of the NDVI. Three CCVI scenarios, based on climate simulations using the representative concentration pathway RCP4.5, showed a greater sensitivity of vegetation towards precipitation in Northern Hemisphere mid latitudes than is currently implemented in climate models. This higher sensitivity is of importance to assess the impact of climate variability on vegetation, in particular on agricultural productivity.

  12. Spectral Cross-Calibration of VIIRS Enhanced Vegetation Index with MODIS: A Case Study Using Year-Long Global Data

    Directory of Open Access Journals (Sweden)

    Kenta Obata

    2016-01-01

    Full Text Available In this study, the Visible Infrared Imaging Radiometer Suite (VIIRS Enhanced Vegetation Index (EVI was spectrally cross-calibrated with the Moderate Resolution Imaging Spectroradiometer (MODIS EVI using a year-long, global VIIRS-MODIS dataset at the climate modeling grid (CMG resolution of 0.05°-by-0.05°. Our cross-calibration approach was to utilize a MODIS-compatible VIIRS EVI equation derived in a previous study [Obata et al., J. Appl. Remote Sens., vol.7, 2013] and optimize the coefficients contained in this EVI equation for global conditions. The calibrated/optimized MODIS-compatible VIIRS EVI was evaluated using another global VIIRS-MODIS CMG dataset of which acquisition dates did not overlap with those used in the calibration. The calibrated VIIRS EVI showed much higher compatibility with the MODIS EVI than the original VIIRS EVI, where the mean error (MODIS minus VIIRS and the root mean square error decreased from ?0.021 to ?0.003 EVI units and from 0.029 to 0.020 EVI units, respectively. Error reductions on the calibrated VIIRS EVI were observed across nearly all view zenith and relative azimuth angle ranges, EVI dynamic range, and land cover types. The performance of the MODIS-compatible VIIRS EVI calibration appeared limited for high EVI values (i.e., EVI > 0.5 due likely to the maturity of the VIIRS dataset used in calibration/optimization. The cross-calibration methodology introduced in this study is expected to be useful for other spectral indices such as the normalized difference vegetation index and two-band EVI.

  13. Identification of croplands of winter cereals in Rio Grande do Sul state, Brazil, through unsupervised classification of normalized difference vegetation index images / Identificação de áreas agrícolas cultivadas com cereais de inverno no Rio Grande do Sul por meio de classificação não supervisionada de imagens de índice de vegetação por diferença normalizada

    Scientific Electronic Library Online (English)

    Amanda H., Junges; Denise C., Fontana; Daniele G., Pinto.

    2013-08-01

    Full Text Available O objetivo deste trabalho foi propor métodos para identificação de áreas agrícolas cultivadas com cereais de inverno na região norte do Rio Grande do Sul. Para isso, foi analisada a evolução do Índice de Vegetação por Diferença Normalizada (NDVI), proveniente de imagens do sensor MODIS, de abril a d [...] ezembro de 2000 a 2008. Foram elaboradas máscaras de cultivo pela subtração de imagens de mínimo NDVI (abril e maio), das de máximo NDVI (junho a outubro). Posteriormente, foi realizada a classificação não supervisionada das imagens (algoritmo Isodata), considerando as áreas pertencentes às máscaras de cultivo. As máscaras de cultivo identificaram pixels com as maiores variações de biomassa verde, associadas ou não à produção de grãos. A classificação não supervisionada gerou classes cujos perfis temporais foram condizentes com corpos d'água, pastagens e cultivos de cereais de inverno para produção de grãos e para cobertura do solo. Os perfis temporais de áreas destinadas à produção de grãos concordaram com os padrões de cultivo dos cereais de inverno na região (ciclo de desenvolvimento, manejo e épocas de semeadura). A classificação não supervisionada de áreas identificadas por máscaras de cultivo permite identificar e monitorar cultivos de cereais de inverno que se assemelham quanto à morfologia e à fenologia. Abstract in english This study aimed to propose methods to identify croplands cultivated with winter cereals in the northern region of Rio Grande do Sul State, Brazil. Thus, temporal profiles of Normalized Difference Vegetation Index (NDVI) from MODIS sensor, from April to December of the 2000 to 2008, were analyzed. F [...] irstly, crop masks were elaborated by subtracting the minimum NDVI image (April to May) from the maximum NDVI image (June to October). Then, an unsupervised classification of NDVI images was carried out (Isodata), considering the crop mask areas. According to the results, crop masks allowed the identification of pixels with greatest green biomass variation. This variation might be associated or not with winter cereals areas established to grain production. The unsupervised classification generated classes in which NDVI temporal profiles were associated with water bodies, pastures, winter cereals for grain production and for soil cover. Temporal NDVI profiles of the class winter cereals for grain production were in agree with crop patterns in the region (developmental stage, management standard and sowing dates). Therefore, unsupervised classification based on crop masks allows distinguishing and monitoring winter cereal crops, which were similar in terms of morphology and phenology.

  14. The response of vegetation dynamics of the different alpine grassland types to temperature and precipitation on the Tibetan Plateau.

    Science.gov (United States)

    Sun, Jian; Qin, Xiaojing; Yang, Jun

    2016-01-01

    The spatiotemporal variability of the Normalized Difference Vegetation Index (NDVI) of three vegetation types (alpine steppe, alpine meadow, and alpine desert steppe) across the Tibetan Plateau was analyzed from 1982 to 2013. In addition, the annual mean temperature (MAT) and annual mean precipitation (MAP) trends were quantified to define the spatiotemporal climate patterns. Meanwhile, the relationships between climate factors and NDVI were analyzed in order to understand the impact of climate change on vegetation dynamics. The results indicate that the maximum of NDVI increased by 0.3 and 0.2 % per 10 years in the entire regions of alpine steppe and alpine meadow, respectively. However, no significant change in the NDVI of the alpine desert steppe has been observed since 1982. A negative relationship between NDVI and MAT was found in all these alpine grassland types, while MAP positively impacted the vegetation dynamics of all grasslands. Also, the effects of temperature and precipitation on different vegetation types differed, and the correlation coefficient for MAP and NDVI in alpine meadow is larger than that for other vegetation types. We also explored the percentages of precipitation and temperature influence on NDVI variation, using redundancy analysis at the observation point scale. The results show that precipitation is a primary limiting factor for alpine vegetation dynamic, rather than temperature. Most importantly, the results can serve as a tool for grassland ecosystem management. PMID:26661956

  15. Differences of fire activity and their underlying factors among vegetation formations in Greece

    Directory of Open Access Journals (Sweden)

    Xystrakis F

    2013-04-01

    Full Text Available Climate and weather play an important role in shaping fire activity patterns by controlling fuel productivity and fire spread, respectively. Additionally, climate is a key factor controlling primary productivity while different climate zones are expected to support different vegetation formations, that on their turn, include different fuel types. The use, therefore, of an underlying phytogeographical framework would provide more comprehensive outputs in exploring fire activity patterns at national scales, instead of using administrative units that could include various types of non-ecological divisions. Within this concept, we examined the recent fire activity of the main forest formations occurring in Greece and we explored their relationships with various weather parameters and indexes. Correlations of number of fires with weather variables, especially among the vegetation formations that summarize most of the human influence were lax, yet burned area showed significant correlations mainly with fire season precipitation totals. The precipitation related variables generally outperformed the temperature-related variables in correlating with both number of fires and burned area. Climatic indexes, which embody the combined effects of precipitation and air temperature, reflected improved correlations, but not to the extent that could allow for the promotion of their use in further modeling.

  16. Comparison of sap flux, moisture flux tower and MODIS enhanced vegetation index methods for estimating riparian evapotranspiration

    Science.gov (United States)

    Nagler, Pamela L.; Glenn, Edward P.; Morino, Kiyomi

    2010-01-01

    Riparian evapotranspiration (ET) was measured on a salt cedar (Tamarix spp.) dominated river terrace on the Lower Colorado River from 2007 to 2009 using tissue-heat-balance sap flux sensors at six sites representing very dense, medium dense, and sparse stands of plants. Salt cedar ET varied markedly across sites, and sap flux sensors showed that plants were subject to various degrees of stress, detected as mid-day depression of transpiration and stomatal conductance. Sap flux results were scaled from the leaf level of measurement to the stand level by measuring plant-specific leaf area index and fractional ground cover at each site. Results were compared to Bowen ratio moisture tower data available for three of the sites. Sap flux sensors and flux tower results ranked the sites the same and had similar estimates of ET. A regression equation, relating measured ET of salt cedar and other riparian plants and crops on the Lower Colorado River to the Enhanced Vegetation Index from the MODIS sensor on the Terra satellite and reference crop ET measured at meteorological stations, was able to predict actual ET with an accuracy or uncertainty of about 20%, despite between-site differences for salt cedar. Peak summer salt cedar ET averaged about 6 mm d-1 across sites and methods of measurement.

  17. Indexing of satellite images with different resolutions by wavelet features

    OpenAIRE

    Luo, Bin; Aujol, Jean-François; Gousseau, Yann; Ladjal, Saïd

    2008-01-01

    As many users of imaging technologies, space agencies are rapidly building up massive image databases. A particularity of these databases is that they are made of images with different but known resolution. In this paper, we introduce a new scheme allowing to index and compare images with different resolution. This scheme relies on a simplified modeling of the acquisition process of satellite images and uses continuous wavelet decompositions. We establish a correspondance between scales that ...

  18. Modelling spatial and temporal vegetation variability with the Climate Constrained Vegetation Index: evidence of CO2 fertilisation and of water stress in continental interiors

    Science.gov (United States)

    Los, S. O.

    2015-06-01

    A model was developed to simulate spatial, seasonal and interannual variations in vegetation in response to temperature, precipitation and atmospheric CO2 concentrations; the model addresses shortcomings in current implementations. The model uses the minimum of 12 temperature and precipitation constraint functions to simulate NDVI. Functions vary based on the Köppen-Trewartha climate classification to take adaptations of vegetation to climate into account. The simulated NDVI, referred to as the climate constrained vegetation index (CCVI), captured the spatial variability (0.82 drought in the Sahel and during dust bowls of the 1930s and 1950s in the Great Plains in North America. A global CO2 fertilisation effect was found in NDVI data, similar in magnitude to that of earlier estimates (8 % for the 20th century). This effect increased linearly with simple ratio, a transformation of the NDVI. Three CCVI scenarios, based on climate simulations using the representative concentration pathway RCP4.5, showed a greater sensitivity of vegetation towards precipitation in Northern Hemisphere mid latitudes than is currently implemented in climate models. This higher sensitivity is of importance to assess the impact of climate variability on vegetation, in particular on agricultural productivity.

  19. Species Composition of Termites (Isoptera in Different Cerrado Vegetation Physiognomies

    Directory of Open Access Journals (Sweden)

    Danilo Elias Oliveira

    2013-07-01

    Full Text Available Little is known about the termite fauna of the different vegetation physiognomies in the Cerrado biome. It is suggested that the species compositions in grassland and savanna areas are closely related to each other, and quite distinct from those of forests. This study compared the species composition from five different physiognomies of Cerrado, and tested the hypothesis that the termite faunas of savannas and grasslands form a distinct group from that of forests. The study was conducted in the Parque Estadual da Serra de Jaraguá, state of Goiás, Brazil. Termites were sampled from two physiognomies of savanna, one natural grassland, one pasture, and one gallery forest. A transect with 10 parcels of 5x2 m was established in each physiognomy. The relative abundance was inferred by the number of encounters, termites were classified in feeding guilds, and the dissimilarity in the species composition between the physiognomies was calculated. A total of 219 encounters, of 42 species of two families were recorded. The most abundant feeding guilds were the humivores (98 and xylophages (55. The physiognomies with the largest number of species were rupestrian cerrado (23 species and cerrado sensu stricto (21. The physiognomies had a similar species composition (less than 55% dissimilarity, mainly the natural open areas. The hypothesis of a distinct fauna of termites in forest vegetation was refuted. The termite fauna of gallery forest is very different from that of pasture, but most species also occur in natural open areas. The impact of pasture on the diversity and composition of termites seems to be significant, but the impact is even greater on the proportion of the feeding guilds, reducing the proportion of xylophages and intermediates.

  20. A simple interpretation of the surface temperature/vegetation index space for assessment of surface moisture status

    DEFF Research Database (Denmark)

    Sandholt, Inge; Rasmussen, Kjeld

    2002-01-01

    A simplified land surface dryness index (Temperature-Vegetation Dryness Index, TVDI) based on an empirical parameterisation of the relationship between surface temperature (T-s) and vegetation index (NDVI) is suggested. The index is related to soil moisture and, in comparison to existing interpretations of the T-s/NDVI space, the index is conceptually and computationally straightforward. It is based on satellite derived information only, and the potential for operational application of the index is therefore large. The spatial pattern and temporal evolution in TVDI has been analysed using 37 NOAA-AVHRR images from 1990 covering part of the Ferlo region of northern, semiarid Senegal in West Africa. The spatial pattern in TVDI has been compared with simulations of soil moisture from a distributed hydrological model based on the MIKE SHE code. The spatial variation in TVDI reflects the variation in moisture on a finer scale than can be derived from the hydrological model in this case. (C) 2002 Elsevier Science Inc. All rights reserved.

  1. Observations of Typhoon Center by Using Satellite-derived Normalized Difference Convection Index

    Science.gov (United States)

    Liu, Chung-Chih; Chen, Chun-Hsu

    2015-04-01

    A technique involving differencing water vapor and infrared window channel brightness temperature values to identify and quantify intense convection in tropical cyclones using bispectral geostationary satellite imagery was proposed by Olander and Velden (2009). Rouse et al. (1974) calculated a normalized ratio of the near infrared and red bands and proposed an index called the normalized difference vegetation index. It was then used in many fields such as estimations of vegetation biomass, leaf area, the proportion of absorbed photosynthetically active radiation, etc. The present study used the spectral features of the IR1 and WV channels of the satellite to define a new index, the brightness temperature of the infrared window channel minus the brightness temperature of the water vapor channel divided by the brightness temperature of the infrared window channel plus the brightness temperature of the water vapor channel. The values obtained by this formula are called the Normalized Difference Convection Index (NDCI) values. The NDCI value is between -1 and 1. The NDCI value at WV = 0K is the highest, 1; while that at IR1 = 0K is the lowest, -1. In cases of a clear sky or atmosphere with thin cloud and dry air, NDCI values should be larger than 0. In cases of a convective cloud system, NDCI values should be lower than 0. In addition, the newly defined NDCI does show significant difference from simple difference of IR1-WV. For example, the NDCI value is -0.0017 at IR1=299K and WV=300K, while the NDCI value is -0.0033 at IR1=149K and WV=150K. The two times difference of NDCI values shows the features of clouds with NDCI value -0.0017 are quite different from those with NDCI value -0.0033. The former may be low level clouds, but the latter may be deep convections. However, the simple difference of IR1-WV cannot be used to distinguish the difference. The NDCI was applied to determine the centers of Typhoon Longwang (2005). The results showed that the two-dimensional NDCI analysis helped to identify positions of overshooting areas. In addition, because the NDCI values near a typhoon eye were rather significant, if a typhoon eye was formed, the NDCI cross-section analysis could help to confirm its position. When the center of a typhoon was covered by the high Anvils and Cirrus Layers, it could still be found qualitatively through the two-dimensional analysis. Keywords:Typhoon, Satellite imagery, Normalized Difference Convection Index

  2. Experimental Study of Flows Induced Scour around compound Vegetation Patch in Different Densities

    Science.gov (United States)

    Chan, Hsun-Chuan; Huang, Tai-Ran

    2015-04-01

    In the natural rivers, woody vegetation commonly grows along the riverbank. When flows run through the woody vegetation zones, the stream processes are markedly affected. Previous studies were to explore Single-density vegetation group. This study used a combination of dual-density vegetation group. We experimentally investigated the flows induced scour around vegetation patch in different density. Since vegetation grows along the nature bank, so the vegetation model is arranged along one side of the flume wall. The experiments were expected to simulate the near bank scour in the jointed effects of vegetation and levee. The woody vegetation was set in 10 square centimeters. Modelled vegetation was simulated by the steel columns in the emergent flow conditions. Uniform sand with a median size of 0.88 mm was used as the bed sediment. The experimental flow was steady and flow velocity was adopted to close to the initiation of sediment motion. It was observed sediment erosion phenomenon around the vegetation zone. The bed morphology of equilibrium scour condition was measured by a Laser Distance Meter in the cases of vegetation density equal to 0.03, 0.04, 0.05, 0.07, 0.09, 0.12, 0.15,0.2, and 0.3. Test result of the vegetation group compound arrangement made by a combination of density 0.03, 0.05, 0.09, and 0.12. The difference between double density and single density of the vegetation was compared. Vegetation densities were used to research the effects of vegetation on the maximum scour depth of the scour hole. Near the vegetation zone, the size of the scour hole increased as the vegetation density increased. However, the height of depositing dune is in a low correlation with vegetation density. Location of Maximum scour depth and the maximum accumulation will move upstream with the density increase.

  3. Differentiating between Land Use and Climate-driven Change using Long-term Vegetation Index Trends adjusted for Precipitation on the Mongolian Plateau

    Science.gov (United States)

    John, R.; Chen, J.; Kim, Y.; Yang, Z.; Xiao, J.; Shao, C.; Batkhishig, O.

    2014-12-01

    The Mongolian plateau is undergoing consistent warming in addition to an increase in extreme climatic events. Land cover/land use change has accelerated over the past three decades, owing to post liberalization socio-economic changes in Inner Mongolia, China (IM) Mongolia (MG) which have different political systems. Extensive anthropomorphic modifications of ecosystems have the ability to alter the structure and function of ecosystems and ecological processes such as the carbon and water cycle and it is therefore important to differentiate between such changes from climate-driven changes. This study identified climate-driven and human-induced changes in vegetation cover on the Mongolian plateau across desert, grassland and forest biomes as well as administrative divisions. We applied non-parametric trend tests on time series of vegetation index datasets that include MODIS EVI, Vegetation Index and Phenology (VIP) EVI2, and GIMMS 3g as well as precipitation and temperature obtained from TRMM and MERRA reanalysis datasets. We then correlated the VI trends with the climate drivers to determine and isolate primary climate drivers. VI residuals obtained from the regression of composites of peak season maximum VI and JJA monthly accumulated rainfall were analyzed for detection of trends in vegetation greenness not explained by rainfall dynamics over different time periods (2000-2012, and 1981 to 2010). In addition, we obtained trends in socioeconomic variables like total livestock and population density which were closely correlated with VI residual trends adjusted for rainfall. Some administrative subdivisions in IM and MG showed a decreasing trend in residuals that could be attributed to anthropogenic activity such as grazing, or urbanization, while other subdivisions showed an increasing trend in residuals increasing trend in residuals suggest that vegetation cover has improved and perhaps be attributed to restoration and conservation efforts.

  4. Genotypic variations in the accumulation of Cd exhibited by different vegetables.

    Science.gov (United States)

    Yang, Junxing; Guo, Haitao; Ma, Yibing; Wang, Liqun; Wei, Dongpu; Hua, Luo

    2010-01-01

    It is an important approach to use the Cd-contaminated soils properly by growing low accumulator or excluder plants for Cd to produce safe foods. To find the suitable vegetable species for growing in Cd-contaminated soils, in the present study the variations in the Cd accumulation for twenty eight vegetable species and several cultivars of five common vegetables (cowpea, kidney pea, bitter gourd, cucumber and squash) were investigated in two soil Cd levels (1 and 2 mg/kg Cd). Experimental results showed that highly significant differences in Cd concentration were evident among 28 vegetables. For example, spinach Cd concentrations were 110-fold and 175-fold higher than that of sweet pea under the 1 and 2 mg/kg Cd exposures, respectively. For Cd accumulation, the order of vegetable species was: leafy vegetables > solanaceous vegetables > kale vegetables > root vegetables > allimus > melon vegetables > legumes. Distinctive differences were also identified when comparing different cultivars of the five common vegetables with an average range of 0.003-0.094 mg/kg Cd. Our results indicated that a large genotypic variation existed among vegetable species or cultivars when subjected to Cd exposure. Therefore, it is important and feasible to elect/breed vegetable species/cultivars with low accumulation of Cd, especially in mildly Cd-contaminated soils. PMID:21179965

  5. Characteristics of methane emission from different vegetations on a wetland

    Science.gov (United States)

    Sugimoto, Atsuko; Fujita, Noboru

    1997-09-01

    Methane flux was observed on a floating mat of temperate sphagnum bog, Mizorogaike, Japan, during the period April to October in 1993, to investigate the factors controlling CH4 emission, especially differences in vegetation and variation of water level. Comparing the CH4 flux among reed dominant site, marsh trefoil (a broad-leaved perennial aquatic herb) dominant site and sphagnum dominant site, the largest CH4 flux was observed at the marsh trefoil site and the smallest flux was at the sphagnum site, reflecting the difference in decomposability of organic matter. Namely, the decomposition rate of marsh trefoil was high, while that of sphagnum was extremely low. At the marsh trefoil site, lowering of the water table below the surface during summer caused an increase of surface soil temperature due to direct exposure to solar radiation. Consequently, it caused a low Eh and enhanced methane production which was supported by the supply of organic matters with high decomposition rate derived from marsh trefoil. At the reed site, CH4 flux increased in late summer. Such a delayed CH4 emission at the reed site was possibly caused by decomposition of roots growing during the summer and delay of soil temperature increase due to the waterlogging. Average CH4 fluxes for seven months were 450, 290, and 70 mgC/m2/day for the marsh trefoil, reed and sphagnum sites, respectively. The ?13C of dissolved CH4, higher than that of bubbles, suggested CH4 oxidation in the soil water. However, oxidation was not a deterministic process controlling CH4 flux at the observed temperate wetland where CH4 production rate was high because of high soil temperature. Sphagnum can only grow in oligotrophic (limited amount of nutrients) water, and its domination suppresses growth of other plants because of low concentration or low availability of nutrients. However, sphagnum can be easily replaced by other wetland plants, if the water in a sphagnum bog becomes rich in nutrients due to water pollution or change in the water circulation in the area. Such a vegetation change from a sphagnum dominant bog to a fen dominated by other wetland plants can accelerate CH4 emission to the atmosphere.

  6. Indexed

    CERN Document Server

    Hagy, Jessica

    2008-01-01

    Jessica Hagy is a different kind of thinker. She has an astonishing talent for visualizing relationships, capturing in pictures what is difficult for most of us to express in words. At indexed.blogspot.com, she posts charts, graphs, and Venn diagrams drawn on index cards that reveal in a simple and intuitive way the large and small truths of modern life. Praised throughout the blogosphere as “brilliant,” “incredibly creative,” and “comic genius,” Jessica turns her incisive, deadpan sense of humor on everything from office politics to relationships to religion. With new material along with some of Jessica’s greatest hits, this utterly unique book will thrill readers who demand humor that makes them both laugh and think.

  7. Seasonal analysis of precipitation, drought and Vegetation index in Indonesian paddy field based on remote sensing data

    Science.gov (United States)

    Darmawan, S.; Takeuchi, W.; Shofiyati, R.; Sari, D. K.; Wikantika, K.

    2014-06-01

    Paddy field is important agriculture crop in Indonesia. Rice is a food staple for 237,6 million Indonesian people. Paddy field growth is strongly influenced by water, but the amount of precipitation is unpredictable. Annual and interannual climate variability in Indonesia is unusual. In recent years remote sensing data has been used for measurement and monitoring of precipitation, drought and Vegetation index such as Global Satellite Mapping of Precipitation (GSMaP), Multi-purpose Transmission SATellite (MTSAT) and Moderate Resolution Imaging Spectroradiometer (MODIS). The objective of this research is to investigate seasonal variability of precipitation, drought and Vegetation index in Indonesian paddy field based on remote sensing data. The methodology consists of collecting of enhanced vegetation index (EVI) from MODIS data, mosaicking of image, collecting of region of interest of paddy field, collecting of precipitation and drought index based on Keetch Bryam Drought Index (KBDI) from GSMaP and MTSAT, and seasonal analysis. The result of this research has showed seasonal variability of precipitation, KBDI and EVI on Indonesia paddy field from 2007 until 2012. Precipitation begins from January until May and October until December, and KBDI begins to increase from June and peak in September only in South Sumatera precipitation almost in all month. Seasonal analysis has showed precipitation and KBDI affect on EVI that can indicate variety phenology of Indonesian paddy field. Peak of EVI occurs before peak of KBDI occurs and increasing of KBDI followed by decreasing of EVI. In 2010 all province got higher precipitation and smaller KBDI so EVI has three peaks such as in West Java that can indicated increasing of rice production.

  8. Accuracy of the Temperature-Vegetation Dryness Index using MODIS under water-limited vs. energy-limited evapotranspiration conditions

    DEFF Research Database (Denmark)

    Garcia, Monica; Ferna?ndez, N.

    2014-01-01

    Water deficit indices based on the spatial relationship between surface temperature (Ts) and NDVI, known as triangle approaches, are widely used for drought monitoring. However, their application has been recently questioned when the main factor limiting evapotranspiration is energy. Even though water is the main control in dryland ecosystems, these can also undergo periods of energy and temperature limitation. In this paper we aimed to: (i) evaluate the TVDI (Temperature-Vegetation Dryness Index) to estimate water deficits (e.g. ratio between actual and potential evapotranspiration), and heat surface fluxes using MODIS data; and (ii) provide insights about the factors most affecting the accuracy of results. Factors considered included the type of climatic control on evapotranspiration, ?E, (i.e. water-limited vs. energy-limited), the quality of Tair estimates, the heterogeneity of land cover types and climatic variables in the region, or the algorithm to extract hydrological boundaries from the images. The TVDI was compared with eddy covariance (EC) data from two shrublands with different climatic controls for ?E in South Spain. Evaluations showed that it could be used to estimate the water deficit when water was the main limiting factor (R=0.81-0.88; Mean Average Error, MAE=0.16-0.17) but not in energy-limited situations (R

  9. Satellite observations of high northern latitude vegetation productivity changes between 1982 and 2008: ecological variability and regional differences

    International Nuclear Information System (INIS)

    To assess ongoing changes in high latitude vegetation productivity we compared spatiotemporal patterns in remotely sensed vegetation productivity in the tundra and boreal zones of North America and Eurasia. We compared the long-term GIMMS (Global Inventory Modeling and Mapping Studies) NDVI (Normalized Difference Vegetation Index) to the more recent and advanced MODIS (Moderate Resolution Imaging Spectroradiometer) NDVI data set, and mapped circumpolar trends in a gross productivity metric derived from the former. We then analyzed how temporal changes in productivity differed along an evergreen-deciduous gradient in boreal Alaska, along a shrub cover gradient in Arctic Alaska, and during succession after fire in boreal North America and northern Eurasia. We find that the earlier reported contrast between trends of increasing tundra and decreasing boreal forest productivity has amplified in recent years, particularly in North America. Decreases in boreal forest productivity are most prominent in areas of denser tree cover and, particularly in Alaska, evergreen forest stands. On the North Slope of Alaska, however, increases in tundra productivity do not appear restricted to areas of higher shrub cover, which suggests enhanced productivity across functional vegetation types. Differences in the recovery of post-disturbance vegetation productivity between North America and Eurasia are described using burn chronosequences, and the potential factors driving regional differences are discussed.

  10. Comparison and Intercalibration of Vegetation Indices from Different Sensors for Monitoring Above-Ground Plant Nitrogen Uptake in Winter Wheat

    Directory of Open Access Journals (Sweden)

    Yan Zhu

    2013-03-01

    Full Text Available Various sensors have been used to obtain the canopy spectral reflectance for monitoring above-ground plant nitrogen (N uptake in winter wheat. Comparison and intercalibration of spectral reflectance and vegetation indices derived from different sensors are important for multi-sensor data fusion and utilization. In this study, the spectral reflectance and its derived vegetation indices from three ground-based sensors (ASD Field Spec Pro spectrometer, CropScan MSR 16 and GreenSeeker RT 100 in six winter wheat field experiments were compared. Then, the best sensor (ASD and its normalized difference vegetation index (NDVI (807, 736 for estimating above-ground plant N uptake were determined (R2 of 0.885 and RMSE of 1.440 g·N·m?2 for model calibration. In order to better utilize the spectral reflectance from the three sensors, intercalibration models for vegetation indices based on different sensors were developed. The results indicated that the vegetation indices from different sensors could be intercalibrated, which should promote application of data fusion and make monitoring of above-ground plant N uptake more precise and accurate.

  11. Satellite observations of high northern latitude vegetation productivity changes between 1982 and 2008: ecological variability and regional differences

    Energy Technology Data Exchange (ETDEWEB)

    Beck, Pieter S A; Goetz, Scott J, E-mail: pbeck@whrc.org [Woods Hole Research Center, 149 Woods Hole Road, Falmouth, MA 02540 (United States)

    2011-10-15

    To assess ongoing changes in high latitude vegetation productivity we compared spatiotemporal patterns in remotely sensed vegetation productivity in the tundra and boreal zones of North America and Eurasia. We compared the long-term GIMMS (Global Inventory Modeling and Mapping Studies) NDVI (Normalized Difference Vegetation Index) to the more recent and advanced MODIS (Moderate Resolution Imaging Spectroradiometer) NDVI data set, and mapped circumpolar trends in a gross productivity metric derived from the former. We then analyzed how temporal changes in productivity differed along an evergreen-deciduous gradient in boreal Alaska, along a shrub cover gradient in Arctic Alaska, and during succession after fire in boreal North America and northern Eurasia. We find that the earlier reported contrast between trends of increasing tundra and decreasing boreal forest productivity has amplified in recent years, particularly in North America. Decreases in boreal forest productivity are most prominent in areas of denser tree cover and, particularly in Alaska, evergreen forest stands. On the North Slope of Alaska, however, increases in tundra productivity do not appear restricted to areas of higher shrub cover, which suggests enhanced productivity across functional vegetation types. Differences in the recovery of post-disturbance vegetation productivity between North America and Eurasia are described using burn chronosequences, and the potential factors driving regional differences are discussed.

  12. A MODIS-based begetation index climatology

    Science.gov (United States)

    Passive microwave soil moisture algorithms must account for vegetation attenuation of the signal in the retrieval process. One approach to accounting for vegetation is to use vegetation indices such as the Normalized Difference Vegetation Index (NDVI) to estimate the vegetation optical depth. The pa...

  13. Comparison of Different Vegetation Indices for Very High-Resolution Images, Specific Case Ultracam-D Imagery

    Science.gov (United States)

    Barzegar, M.; Ebadi, H.; Kiani, A.

    2015-12-01

    Today digital aerial images acquired with UltraCam sensor are known to be a valuable resource for producing high resolution information of land covers. In this research, different methods for extracting vegetation from semi-urban and agricultural regions were studied and their results were compared in terms of overall accuracy and Kappa statistic. To do this, several vegetation indices were first tested on three image datasets with different object-based classifications in terms of presence or absence of sample data, defining other features and also more classes. The effects of all these cases were evaluated on final results. After it, pixel-based classification was performed on each dataset and their accuracies were compared to optimum object-based classification. The importance of this research is to test different indices in several cases (about 75 cases) and to find the quantitative and qualitative effects of increasing or decreasing auxiliary data. This way, researchers who intent to work with such high resolution data are given an insight on the whole procedure of detecting vegetation species as one of the outstanding and common features from such images. Results showed that DVI index can better detect vegetation regions in test images. Also, the object-based classification with average 93.6% overall accuracy and 86.5% Kappa was more suitable for extracting vegetation rather than the pixel-based classification with average 81.2% overall accuracy and 59.7% Kappa.

  14. DEVELOPMENT OF AN INDEX OF ALIEN SPECIES INVASIVENESS: AN AID TO ASSESSING RIPARIAN VEGETATION CONDITION

    Science.gov (United States)

    Many riparian areas are invaded by alien plant species that negatively affect native species composition, community dynamics and ecosystem properties. We sampled vegetation along reaches of 31 low order streams in eastern Oregon, and characterized species assemblages at patch an...

  15. Plasma Electrophoresis and Phagocytic Index Screening of Some Indigenous Vegetables Subjected to Preclinical Models

    Directory of Open Access Journals (Sweden)

    Vikas Sharma

    2011-04-01

    Full Text Available

    50 % of methanolic extract Colocasia esculenta, Moringa oliefera, Luffa cylindrica, and Hibiscus esculentus were subjected to immunomodulatory activity in Swiss albino mice either sex. Mice were treated with five days of dosing of Colocasia esculenta 50 mg/kg bw, Colocasia esculenta 100 mg/kg bw, Moringa oliefera 200mg/kg bw, Moringa oleifera 400 mg/kg bw, Luffa cylindrica 100 mg/kg bw, Luffa cylindrica 200 mg/kg bw, Hibiscus esculentus 100 mg/kg bw, and Hibiscus esculentus 200 mg/kg bw. Cyclosporine (2.5 mg/kg used as a standard reference drug for 5 days. Investigation of immunomodulator activity of these 50 % of methanolic extract of drugs to parentage of yeast digestion form 24 hours the peritoneal fluid culture and electrophoretic plasma protein band albumin, alpha 1, alpha 2, beta and gamma respectively from blood plasma were observed using parameters phagocytosis and plasma electrophoresis. Also investigated the ulcerogenic effect or any toxic effect of plant extract by histopathology study of crypt, villi and goblet cells with reference to standard drug cyclosporine. As regards these parameters, Hibiscus esculentus 100 and 200 mg/ kg bw dose, Moringa oleifera 200 and 400 mg/ kg bw dose and Luffa cylindrica 200mg/kg bw elicited a moderately significant increase in the % of yeast digestion (P < 0.001 respectively and Luffa cylindrica 100mg/kg bw significant increase in the % of yeast digestion (P < 0.01. Hibiscus esculentus showed significant dose dependent increase and Moringa oleifera decrease phagocytic activity of macrophages. Hibiscus esculentus 200 mg/ kg bw dose and Moringa oleifera 200 significantly increased (P < 0.01 the Gamma globulin.However, our present study revealed and signatured for their immunomodulator enhancing property. As in Asian subcontinent daily there vegetables are cooked and served with know and unknown of its potential function against different diseases. If there vegetables properly ruled out for their pharmacological aspect then it may add diamond in the crown of dietician which has been bother every day today life but over looked exponetentially.

    Keywords:- Colocasia esculenta, Moringa oliefera, Luffa cylindrica, and Hibiscus esculentus

  16. Vitamin E and Beta Carotene Composition in Four Different Vegetable Oils

    OpenAIRE

    Ab. G.M. Top; Halimah Muhamad; Aminah Abdullah; Halimah A. Sani; Eqbal Dauqan

    2011-01-01

    Problem statement: Some vegetable oils contains natural antioxidants such as beta carotene and vitamin E namely tocopherol and tocotrienol. Different vegetable oils contained different amount of vitamin E and β-carotene. Approach: Study was carried out to investigate the natural antioxidants (vitamin E and beta carotene) composition in four different vegetable oils [Red Palm Olein (RPO), palm plein (PO), Corn Oil (CO) and Coconut Oil (COC)]. Results: The results showe...

  17. Impact of the construction of a large dam on riparian vegetation cover at different elevation zones as observed from remotely sensed data

    Science.gov (United States)

    Kellogg, Christopher H.; Zhou, Xiaobing

    2014-10-01

    The impact of the construction of a large dam on riparian vegetation cover can be multifold. How the riparian vegetation cover changes at different elevation zones in response to the construction of a large dam and the subsequent impound of reservoir water is still an open question. In this study, we used satellite remote sensing data integrated with geographic information system (GIS) to monitor vegetation cover change at different riparian elevation zones on a large spatial scale, taking the Three Gorges Dam in China as an example. Due to the large scale of this newly formed reservoir, it is expected to impact the riparian vegetation canopy both directly and indirectly. We chose to monitor vegetation cover changes along the 100 km riparian stretch of river directly upstream of the Three Gorges Dam site, over the construction period of eleven years (2000-2010), using MODIS vegetation indices products, digital elevation model (DEM) data from ASTER, and the time series water level data of the Three Gorges reservoir as the data sources. Results show that non-vegetated area increased in the inundated zone (below 175 m), as expected; area of densely vegetated land cover increased within the elevation zone of 175-775 m and no change in vegetation cover was observed above 775 m in elevation. Regression analysis between the vegetation index data and the reservoir water level shows that increasing water levels have had a negative impact on vegetation cover below 175 m, a positive impact on vegetation cover is limited to the region between 175 and 775 m, and no significant impact was observed above 775 m. MODIS EVI product is less sensitive in mapping non-vegetated land cover change, but more sensitive in mapping vegetated land cover change, caused by the reservoir water level variation; both products are similar in effectively tracking a trend between land cover change in each elevation zone with time or with reservoir water level.

  18. A survey of drought and Variation of Vegetation by statistical indexes and remote sensing (Case study: Jahad forest in Bandar Abbas)

    Science.gov (United States)

    Tamassoki, E.; Soleymani, Z.; Bahrami, F.; Abbasgharemani, H.

    2014-06-01

    The damages of drought as a climatic and creeping phenomenon are very enormous specially in deserts. Necessity of management and conflict with it is clear. In this case vegetation are damaged too, and even are changed faster. This paper describes the process of vegetation changes and surveys it with drought indexes such as statistical and remote sensing indexes and correlation between temperature and relative humidity by Geographical Information System (GIS) and Remote Sensing (RS) in forest park of Bandar Abbas in successive years. At the end the regression and determination-coefficient for showing the importance of droughts survey are computed. Results revealed that the correlation between vegetation and indexes was 0.5. The humidity had maximum correlation and when we close to 2009 the period of droughts increase and time intervals decrease that influence vegetation enormously and cause the more area lost its vegetation.

  19. Evaluation of habitat suitability index models by global sensitivity and uncertainty analyses: a case study for submerged aquatic vegetation.

    Science.gov (United States)

    Zajac, Zuzanna; Stith, Bradley; Bowling, Andrea C; Langtimm, Catherine A; Swain, Eric D

    2015-07-01

    Habitat suitability index (HSI) models are commonly used to predict habitat quality and species distributions and are used to develop biological surveys, assess reserve and management priorities, and anticipate possible change under different management or climate change scenarios. Important management decisions may be based on model results, often without a clear understanding of the level of uncertainty associated with model outputs. We present an integrated methodology to assess the propagation of uncertainty from both inputs and structure of the HSI models on model outputs (uncertainty analysis: UA) and relative importance of uncertain model inputs and their interactions on the model output uncertainty (global sensitivity analysis: GSA). We illustrate the GSA/UA framework using simulated hydrology input data from a hydrodynamic model representing sea level changes and HSI models for two species of submerged aquatic vegetation (SAV) in southwest Everglades National Park: Vallisneria americana (tape grass) and Halodule wrightii (shoal grass). We found considerable spatial variation in uncertainty for both species, but distributions of HSI scores still allowed discrimination of sites with good versus poor conditions. Ranking of input parameter sensitivities also varied spatially for both species, with high habitat quality sites showing higher sensitivity to different parameters than low-quality sites. HSI models may be especially useful when species distribution data are unavailable, providing means of exploiting widely available environmental datasets to model past, current, and future habitat conditions. The GSA/UA approach provides a general method for better understanding HSI model dynamics, the spatial and temporal variation in uncertainties, and the parameters that contribute most to model uncertainty. Including an uncertainty and sensitivity analysis in modeling efforts as part of the decision-making framework will result in better-informed, more robust decisions. PMID:26257866

  20. Bioclimatic and vegetation mapping of a topographically complex oceanic island applying different interpolation techniques

    Science.gov (United States)

    Garzón-Machado, Víctor; Otto, Rüdiger; del Arco Aguilar, Marcelino José

    2014-07-01

    Different spatial interpolation techniques have been applied to construct objective bioclimatic maps of La Palma, Canary Islands. Interpolation of climatic data on this topographically complex island with strong elevation and climatic gradients represents a challenge. Furthermore, meteorological stations are not evenly distributed over the island, with few stations at high elevations. We carried out spatial interpolations of the compensated thermicity index (Itc) and the annual ombrothermic Index (Io), in order to obtain appropriate bioclimatic maps by using automatic interpolation procedures, and to establish their relation to potential vegetation units for constructing a climatophilous potential natural vegetation map (CPNV). For this purpose, we used five interpolation techniques implemented in a GIS: inverse distance weighting (IDW), ordinary kriging (OK), ordinary cokriging (OCK), multiple linear regression (MLR) and MLR followed by ordinary kriging of the regression residuals. Two topographic variables (elevation and aspect), derived from a high-resolution digital elevation model (DEM), were included in OCK and MLR. The accuracy of the interpolation techniques was examined by the results of the error statistics of test data derived from comparison of the predicted and measured values. Best results for both bioclimatic indices were obtained with the MLR method with interpolation of the residuals showing the highest R 2 of the regression between observed and predicted values and lowest values of root mean square errors. MLR with correction of interpolated residuals is an attractive interpolation method for bioclimatic mapping on this oceanic island since it permits one to fully account for easily available geographic information but also takes into account local variation of climatic data.

  1. The study of vegetation indices for the monitoring of differences in chlorophyll and carotenoid composition in green vegetables

    Science.gov (United States)

    Meulebroeck, Wendy; Thienpont, Hugo

    2012-04-01

    In this paper we studied the reflectance spectra of different green vegetables. The main objective was to identify the wavelength(s)(areas) that are the most sensitive to variations in pigment composition. With this we try to meet the ever growing demand from society to classify food products on their quality which is related to the state of ripening and degradation. The group of investigated samples consisted of a group of seven different green vegetables. Because these products have different pigment compositions they formed the ideal test samples for our research. For each product type we measured the reflectance spectra between 400 and 800 nm for 30 samples. From these spectra we investigated three different types of measurands: the measurands that are nowadays commonly used to monitor color differences, the vegetation indices that are defined to monitor plant leaves and measurands that are taking into account the entire reflectance spectrum in the visible part of the electromagnetic spectrum. The main conclusion of our research was that a combination of the first two mentioned types of indices allowed us to identify the different product groups in an optical way.

  2. Index

    OpenAIRE

    Editörden .

    2014-01-01

    ed and indexed in Copernicus, Index Google Scholarship, the PSCR, DOAJ, Research Bible, Indian Open Access Journals (OAJ), Institutional Repositories (IR), Journal TOCs, J-Gate (Informatics India), Ulrich’s, ResearchGate, International Society of Universal Research in Sciences, DRJI, EyeSource

  3. Index

    OpenAIRE

    Editörden .

    2013-01-01

    ed and indexed in Copernicus, Index Google Scholarship, the PSCR, DOAJ, Research Bible, Indian Open Access Journals (OAJ), Institutional Repositories (IR), Journal TOCs, J-Gate (Informatics India), Ulrich’s, ResearchGate, International Society of Universal Research in Sciences, DRJI, EyeSource

  4. Efficient retrieval of vegetation leaf area index and canopy clumping factor from satellite data to support pollutant deposition assessments

    Energy Technology Data Exchange (ETDEWEB)

    Nikolov, Ned [Natural Resource Research Center, 2150 Centre Avenue, Building A, Room 368, Fort Collins, CO 80526 (United States)]. E-mail: nnikolov@fs.fed.us; Zeller, Karl [USDA FS Rocky Mountain Research Station, 240 W. Prospect Road, Fort Collins, CO 80526 (United States)]. E-mail: kzeller@fs.fed.us

    2006-06-15

    Canopy leaf area index (LAI) is an important structural parameter of the vegetation controlling pollutant uptake by terrestrial ecosystems. This paper presents a computationally efficient algorithm for retrieval of vegetation LAI and canopy clumping factor from satellite data using observed Simple Ratios (SR) of near-infrared to red reflectance. The method employs numerical inversion of a physics-based analytical canopy radiative transfer model that simulates the bi-directional reflectance distribution function (BRDF). The algorithm is independent of ecosystem type. The method is applied to 1-km resolution AVHRR satellite images to retrieve a geo-referenced data set of monthly LAI values for the conterminous USA. Satellite-based LAI estimates are compared against independent ground LAI measurements over a range of ecosystem types. Verification results suggest that the new algorithm represents a viable approach to LAI retrieval at continental scale, and can facilitate spatially explicit studies of regional pollutant deposition and trace gas exchange. - The paper presents a physics-based algorithm for retrieval of vegetation LAI and canopy-clumping factor from satellite data to assist research of pollutant deposition and trace-gas exchange. The method is employed to derive a monthly LAI dataset for the conterminous USA and verified at a continental scale.

  5. Analysis of Leaf Area Index and Fraction of PAR Absorbed by Vegetation Products from the Terra MODIS Sensor: 2000-2005

    Science.gov (United States)

    Yang, Wenze; Huang, Dong; Tan, Bin; Stroeve, Julienne C.; Shabanov, Nikolay V.; Knyazikhin, Yuri; Nemani, Ramakrishna R.; Myneni, Ranga B.

    2006-01-01

    The analysis of two years of Collection 3 and five years of Collection 4 Terra Moderate Resolution Imaging Spectroradiometer (MODIS) Leaf Area Index (LAI) and Fraction of Photosynthetically Active Radiation (FPAR) data sets is presented in this article with the goal of understanding product quality with respect to version (Collection 3 versus 4), algorithm (main versus backup), snow (snow-free versus snow on the ground), and cloud (cloud-free versus cloudy) conditions. Retrievals from the main radiative transfer algorithm increased from 55% in Collection 3 to 67% in Collection 4 due to algorithm refinements and improved inputs. Anomalously high LAI/FPAR values observed in Collection 3 product in some vegetation types were corrected in Collection 4. The problem of reflectance saturation and too few main algorithm retrievals in broadleaf forests persisted in Collection 4. The spurious seasonality in needleleaf LAI/FPAR fields was traced to fewer reliable input data and retrievals during the boreal winter period. About 97% of the snow covered pixels were processed by the backup Normalized Difference Vegetation Index-based algorithm. Similarly, a majority of retrievals under cloudy conditions were obtained from the backup algorithm. For these reasons, the users are advised to consult the quality flags accompanying the LAI and FPAR product.

  6. Estimation of Anticipated Performance Index and Air Pollution Tolerance Index and of vegetation around the marble industrial areas of Potwar region: bioindicators of plant pollution response.

    Science.gov (United States)

    Noor, Mehwish Jamil; Sultana, Shazia; Fatima, Sonia; Ahmad, Mushtaq; Zafar, Muhammad; Sarfraz, Maliha; Balkhyour, Masour A; Safi, Sher Zaman; Ashraf, Muhammad Aqeel

    2015-06-01

    Mitigating industrial air pollution is a big challenge, in such scenario screening of plants as a bio monitor is extremely significant. It requires proper selection and screening of sensitive and tolerant plant species which are bio indicator and sink for air pollution. The present study was designed to evaluate the Air Pollution Tolerance Index (APTI) and Anticipated Performance Index (API) of the common flora. Fifteen common plant species from among trees, herb and shrubs i.e. Chenopodium album (Chenopodiaceae), Parthenium hysterophorus (Asteraceae), Amaranthus viridis (Amaranthaceae), Lantana camara (Verbenaceaea), Ziziphus nummulari (Rhamnaceae), Silibum merianum (Asteraceae), Cannabis sativa (Cannabinaceae), Calatropis procera (Asclepediaceae), Ricinus communis (Euphorbiaceae), Melia azadirachta (Meliaceae), Psidium guajava (Myrtaceae), Eucalyptus globules (Myrtaceae), Broussonetia papyrifera (Moraceae), Withania somnifera (Solanaceae) and Sapium sabiferum (Euphorbiaceae) were selected growing frequently in vicinity of Marble industries in Potwar region. APTI and API of selected plant species were analyzed by determining important biochemical parameter i.e. total chlorophyll, ascorbic acid, relative water content and pH etc. Furthermore the selected vegetation was studied for physiological, economic, morphological and biological characteristics. The soil of studied sites was analyzed. It was found that most the selected plant species are sensitive to air pollution. However B. papyrifera, E. globulus and R. communis shows the highest API and therefore recommended for plantation in marble dust pollution stress area. PMID:25503327

  7. Differences in the dry deposition of gaseous elemental I-131 to several leafy vegetable species

    Energy Technology Data Exchange (ETDEWEB)

    Shinonaga, T.; Heuberger, H.; Tschiersch, J. [GSF-National Research Center for Environment and Health, Institute of Radiation Protection, Neuherberg, Germany, IAEA Laboratories, Seibersdorf (Austria)

    2004-07-01

    The height of the dry deposition of gaseous elemental {sup 131}I to leafy vegetable is quite uncertain because of the different habit, surface texture and leaf uptake of the different plant species. There is no comparative data on the deposition to various species, but leafy vegetables are taken as reference plants for the estimation of the height of contamination of vegetable foods after a nuclear accident. Therefore new chamber experiments were performed to determine under homogeneous and controlled conditions the dry deposition of gaseous elemental {sup 131}I on mature leafy vegetable. The simultaneous exposition of endive, head lettuce, red oak leaf lettuce and spinach (spring leafy vegetable) rsp. curly kale, white cabbage and spinach (summer leafy vegetable) was arranged. The sample collective of each species was such large that for the expected variation of the results a statistically firm analysis was possible. Significant differences were observed for the {sup 131}I deposition on spring vegetable: the deposition on spinach was roughly 3 times that on leaf lettuce, 4 times that on endive and 9 times that on head lettuce. All summer vegetables showed differences in deposition. For Iodine, the deposition on spinach was roughly 3 times (6 times) that on curly kale and 35 times (100 times) that on white cabbage in the 2 experiments. Washing by deionised water could reduce the contamination only by about 10% for {sup 131}I. (author)

  8. Comparative analysis of different uni- and multi-variate methods for estimation of vegetation water content using hyper-spectral measurements

    Science.gov (United States)

    Mirzaie, M.; Darvishzadeh, R.; Shakiba, A.; Matkan, A. A.; Atzberger, C.; Skidmore, A.

    2014-02-01

    Assessment of vegetation water content is critical for monitoring vegetation condition, detecting plant water stress, assessing the risk of forest fires and evaluating water status for irrigation. The main objective of this study was to investigate the performance of various mono- and multi-variate statistical methods for estimating vegetation water content (VWC) from hyper-spectral data. Hyper-spectral data is influenced by multi-collinearity because of a large number of (independent) spectral bands being modeled by a small number of (dependent) biophysical variables. Therefore, some full spectrum methods that are known to be suitable for analyzing multi-collinear data set were chosen. Canopy spectral reflectance was obtained with a GER 3700 spectro-radiometer (400-2400 nm) in a laboratory setting and VWC was measured by calculating wet/dry weight difference per unit of ground area (g/m2) of each plant canopy (n = 95). Three multivariate statistical methods were applied to estimate VWC: (1) partial least square regression, (2) artificial neural network and (3) principal component regression. They were selected to minimize the problem related to multi-collinearity. For comparison, uni-variate techniques including narrow band ratio water index (RWI), normalized difference water index (NDWI), second soil adjusted vegetation index (SAVI2) and transferred soil adjusted vegetation index (TSAVI) were applied. For each type of vegetation index, all two-band combinations were evaluated to determine the best band combination. Validation of the methods was based on the cross validation procedure and using three statistical indicators: R2, RMSE and relative RMSE. The cross-validated results identified PLSR as the regression model providing the most accurate estimates of VWC among the various methods. The result revealed that this model is highly recommended for use with multi-collinear datasets (RCV2=0.94, RRMSECV = 0.23). Principal component regression exhibited the lowest accuracy among the multivariate models (RCV2=0.78, RRMSECV = 0.41).

  9. Soil borne gungi associated with different vegetable crop in sindh, pakistan

    International Nuclear Information System (INIS)

    Different soil-borne fungi are responsible for reducing the yield of vegetables throughout the world including Pakistan. There are several soil borne fungal pathogens which aggressively infect vegetable crops. Surveys conducted during September 2010 to October 2011, demonstrated that a great diversity of soil borne plant pathogens associated with different vegetables prevail in vegetable growing areas of Sindh such as Tando Allahayar, Mirpurkhas, Ghotaki, Khairpur, Kunri, Umerkot and Karachi, etc. Our study noted in total thirteen different genera of fungi isolated from vegetable crops (cabbage, brinjal, tomato, radish and spinach). Isolated fungi identified included Alternaria solani, Aspergillus flavus, A. fumigatus, A. niger, A. oryzae, A. terrus, Aeromonium fusidiocles, Cladosporium sp., Drechselra hawaiiensis, Eurotium berbanbrum, Fusarium oxysporum, Macrophomina phaseolina, Penicillium commune, Rhizoctonia solani, Trichoderma harzianum, Ulocladium sp., and unidentified black mycelium from the soil and roots of vegetable crops. In addition, it was found that soil is commonly infected by soil-borne fungi and eventually results in heavy losses of vegetable yield in the vegetable growing areas of Sindh province. The infection rapidly increased due to many factors such as, presence of moisture, excess of water and infection may be caused by winds, gales and dust storms as well as by mechanical vectors. (author)

  10. Differences between Sand and Gravel Bars of Streams in Patterns of Vegetation Succession

    Directory of Open Access Journals (Sweden)

    Lee, Chang-Seok

    2009-02-01

    Full Text Available We analyzed the factors driving succession and the structure, and dynamics of vegetation on sandand gravel bars in order to clarify the differences in vegetation succession in rivers with different river bed substrates.Woody plant communities (dominated by Salix, perennial herb communities (dominated by Miscanthus,and annual plant communities (dominated by Persicaria appeared in that order from upstream to downstreamon the sandbar. The results of DCA ordination based on vegetation data reflected a successional trend. Thisresult suggests that sandbars grow in a downstream direction. Various vegetation types different in successionalstage, such as grassland, young stands of Korean red pine (Pinus densiflora, two-layered stands of young andmature pines, and mature pine stands also occurred on gravel bars, but the vegetation in earlier successionalstage was established upstream, which is the opposite to the direction found on sandbars. Those resultsdemonstrate that the dynamics of the bed load itself could be a factor affecting vegetation succession in rivers.In fact, sands suspended by running water were transported downstream over the vegetated area of sand barand thereby created new areas of sandbar on the downstream end of the sandbar. Meanwhile, gravel, whichis heavy and thereby is shifted by strong water currents, accumulated on the upstream end of the vegetatedarea, and thus created new areas of gravel bar in that direction. These results showed that allogenic processesdrive vegetation succession on sand and gravel bars in streams and rivers.

  11. A Different Kind of Publishing; Subject Listings; Library Distributors; Publisher Index; Index to Advertisers; Best Sellers.

    Science.gov (United States)

    Bryant, Eric; Kim, Ann; Miller, Rebecca; Ward, Nathan

    2002-01-01

    This annual supplement discusses issues related to reference books and the publishing industry. Highlights include producing reference books for the library market; a bibliography of over 1000 titles organized by categories and indicating appropriate grade levels; a descriptive list of library distributors; a publisher's index; and a list of the…

  12. A 30-Year Multi-Sensor Vegetation Index and Land Surface Phenology Data Record: Methods Challenges and Potentials

    Science.gov (United States)

    Didan, K.; Barreto-munoz, A.; Miura, T.; Tsend-Ayush, J.

    2013-12-01

    During the last five years the Vegetation Index and Phenology Lab. (vip.arizona.edu) embarked on an effort to process a global multi-sensor Earth Science Data Record of NDVI, EVI2, and land surface Phenology. Data from AVHRR, MODIS, and SPOT-VGT, covering the period 1981 to present, were processed into a seamless and sensor independent record using a suite of community algorithms for data filtering, across-sensor continuity, Vegetation Index (NDVI and EVI2), land surface Phenology, and spatial and temporal gap filling. Currently at Version 3.0 these ESDRs are suitable for the study of land surface vegetation dynamics, long term change and trends, anomalies, and can support various ecosystem and climate modeling efforts by providing key parameters. While adapting the various algorithms to processing this new data record many challenges emerged, ranging from excessive missing and poor quality data to complex and temporally dependent divergence across the various sensors making continuity quite difficult. The first step to addressing these challenges was the adoption of very strict and low tolerance to noise data filters, where the intrinsic input data quality is used along with the long term expected dynamic range to screen for outliers and poor quality. A sophisticated and explicit per-pixel and seasonally dependent across-sensor translation algorithm was developed to address the continuity more properly. To generate the land surface phenology we adapted various community algorithms to work with and take advantage of this new record. Both the standard MODIS Vegetation dynamic algorithm and an in-house homogeneous cluster algorithm were applied to the data. We've also completed a spatially and temporally explicit error and uncertainty characterization of this record. Results indicate a VI error in the range of 5-10% VI units and a 5-40 days error in the date dependent phenology parameters, with an average error of 15 days. This VIP record accounts now for more than 30 years of Earth surface observation. Now in its third generation (V3) this record is capable of supporting environmental, resources management and climate studies as well provide for the parameterization of various ecosystem and climate models. All data are public and are available via a highly interactive online tool, the VIP Data Explorer (vip.arizona.edu/viplab_data_explorer.php) and concurrently via the LP-DAAC.

  13. A New Equation for Deriving Vegetation Phenophase from Time Series of Leaf Area Index (LAI Data

    Directory of Open Access Journals (Sweden)

    Mingliang Che

    2014-06-01

    Full Text Available Accurately modeling the land surface phenology based on satellite data is very important to the study of vegetation ecological dynamics and the related ecosystem process. In this study, we developed a Sigmoid curve (S-curve function by integrating an asymmetric Gaussian function and a logistic function to fit the leaf area index (LAI curve. We applied the resulting asymptotic lines and the curvature extrema to derive the vegetation phenophases of germination, green-up, maturity, senescence, defoliation and dormancy. The new proposed S-curve function has been tested in a specific area (Shangdong Province, China, characterized by a specific pattern in leaf area index (LAI time course due to the dominant presence of crops. The function has not yet received any global testing. The identified phenophases were validated against measurement stations in Shandong Province. (i From the site-scale comparison, we find that the detected phenophases using the S-curve (SC algorithm are more consistent with the observations than using the logistic (LC algorithm and the asymmetric Gaussian (AG algorithm, especially for the germination and dormancy. The phenological recognition rates (PRRs of the SC algorithm are obviously higher than those of two other algorithms. The S-curve function fits the LAI curve much better than the logistic function and asymmetric Gaussian function; (ii The retrieval results of the SC algorithm are reliable and in close proximity to the green-up observed data whether using the AVHRR LAI or the improved MODIS LAI. Three inversion algorithms shows the retrieval results based on AVHRR LAI are all later than based on improved MODIS LAI. The bias statistics reveal that the retrieval results based on the AVHRR LAI datasets are more reasonable than based on the improved MODIS LAI datasets. Overall, the S-curve algorithm has the advantage of deriving vegetation phenophases across time and space as compared to the LC algorithm and the AG algorithm. With the SC algorithm, the vegetation phenophases can be extracted more effectively.

  14. Different index contrast silica-on-silicon waveguides by PECVD

    DEFF Research Database (Denmark)

    Ou, Haiyan

    2003-01-01

    Ge-doped silica-on-silicon waveguides with index steps of 0.01 and 0.02 were fabricated by a combination of plasma enhanced chemical vapour deposition (PECVD) and reactive ion etching (RIE) techniques, and their characteristics, including propagation loss, coupling loss with standard singlemode...

  15. Evaluation of Microclimatic Data on Localities with Different Ratio of Vegetation in Urban Environment

    Directory of Open Access Journals (Sweden)

    Keresztesová So?a

    2014-12-01

    Full Text Available Many authors (Akbari, Taha, 1992; ?aboun, 2008; Klein, 2013; Keresztesová, 2013 proved the influence of vegetation on microclimate as well as on the decrease of heat islands. We were interested in how different ratio of vegetation and open spaces influences microclimatic factors. From April to July 2012 microclimatic factors of two different localities with respect to various ratios of vegetation and open spaces were observed in Nitra, Slovakia. More specifically we observed the air temperature, relative air humidity and surface temperatures of four selected points in both localities. We have found out that in the park, i.e. in the locality with a higher portion of vegetation than open space was the course of temperatures more balanced, thanks to the attribute of vegetation to keep a stable microclimate. We have not observed any major Differences between the monitored points variously located in the vegetation in one locality, but on the other hand, we have observed remarkable differences between the two monitored localities. We may allege that the ratio of vegetation and open spaces makes significant contribution to microclimatic conditions of urban environment.

  16. Evaluating the influence of different vegetation biomes on the global climate

    Energy Technology Data Exchange (ETDEWEB)

    Snyder, P.K.; Foley, J.A. [Nelson Institute for Environmental Studies, University of Wisconsin, Center for Sustainability and the Global Environment (SAGE), 1710, University Avenue Madison, WI 53726 (United States); University of Wisconsin, Department of Atmospheric and Oceanic Sciences, Madison, WI 53706 (United States); Delire, C. [Nelson Institute for Environmental Studies, University of Wisconsin, Center for Sustainability and the Global Environment (SAGE), 1710, University Avenue Madison, WI 53726 (United States)

    2004-09-01

    The participation of different vegetation types within the physical climate system is investigated using a coupled atmosphere-biosphere model, CCM3-IBIS. We analyze the effects that six different vegetation biomes (tropical, boreal, and temperate forests, savanna, grassland and steppe, and shrubland/tundra) have on the climate through their role in modulating the biophysical exchanges of energy, water, and momentum between the land-surface and the atmosphere. Using CCM3-IBIS we completely remove the vegetation cover of a particular biome and compare it to a control simulation where the biome is present, thereby isolating the climatic effects of each biome. Results from the tropical and boreal forest removal simulations are in agreement with previous studies while the other simulations provide new evidence as to their contribution in forcing the climate. Removal of the temperate forest vegetation exhibits behavior characteristic of both the tropical and boreal simulations with cooling during winter and spring due to an increase in the surface albedo and warming during the summer caused by a reduction in latent cooling. Removal of the savanna vegetation exhibits behavior much like the tropical forest simulation while removal of the grassland and steppe vegetation has the largest effect over the central United States with warming and drying of the atmosphere in summer. The largest climatic effect of shrubland and tundra vegetation removal occurs in DJF in Australia and central Siberia and is due to reduced latent cooling and enhanced cold air advection, respectively. Our results show that removal of the boreal forest yields the largest temperature signal globally when either including or excluding the areas of forest removal. Globally, precipitation is most affected by removal of the savanna vegetation when including the areas of vegetation removal, while removal of the tropical forest most influences the global precipitation excluding the areas of vegetation removal. (orig.)

  17. Determination of free thyroxin index in different thyroid diseases

    International Nuclear Information System (INIS)

    A method is described for assessing thyroid function of the total thyroxine and T3-incorporation values, the latter determines the free capacity of the thyroxine-binding globulin (TBG). The so called free thyroxine index (FT4) is calculated. It is proportional to the free serum thyroxine and gives indirect information on the TBG-status of the patient. Test sets STAT3 and STAT4 (Oxford Lab.) were used. Sixty individuals were subjected to examination: 18 without thyroid disease and 42 patients with proven thyroid diseases (hyperthyreoidism, hypothyreoidism, goiter). The normal range of free thyroxine index was 4,9 to 10,0. The divergencies in FT4 in a variety of functional states of the thyroid gland are discussed. (author)

  18. Vitamin E and Beta Carotene Composition in Four Different Vegetable Oils

    Directory of Open Access Journals (Sweden)

    Ab. G.M. Top

    2011-01-01

    Full Text Available Problem statement: Some vegetable oils contains natural antioxidants such as beta carotene and vitamin E namely tocopherol and tocotrienol. Different vegetable oils contained different amount of vitamin E and β-carotene. Approach: Study was carried out to investigate the natural antioxidants (vitamin E and beta carotene composition in four different vegetable oils [Red Palm Olein (RPO, palm plein (PO, Corn Oil (CO and Coconut Oil (COC]. Results: The results showed that RPO contained the highest amount of vitamin E and β-carotene compared to the other three types of vegetable oils studied. Conclusion: The RPO can be considered as a good source of natural antioxidant (tocopherol, tocotrienol and β-carotene.

  19. Reestablishment of wetland vegetation on gas pipeline rights-of-way in six different wetland ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Zimmerman, R.E. Shem, L.; Wilkey, P.L. [Argonne National Lab., IL (United States); Van Dyke, G.D. [Trinity Christian Coll. Palos Heights, IL (United States); Hackney, C. [North Carolina Univ., Wilmington, NC (United States); Gowdy, M. [Institute of Technology, Chicago, IL (United States)

    1992-05-01

    Vegetational surveys were carried out to compare reestablished vegetation on pipeline rights-of-way (ROWS) with that in adjacent natural ecosystems undisturbed by pipeline installation. Six sites of various ages were surveyed in ecosystems ranging from coastal marsh to forested wetland. At all sites except one, both the number and the percentage of wetland species on the ROW approximated or exceeded those in the adjacent natural area. In four ecosystems, the vegetation on the ROW was limited to a herbaceous layer by ROW maintenance; thus, the ROWs often involved a complex of species quite different from that found in the adjacent ecosystems.

  20. SPECIES COMPOSITION OF WEED VEGETATION IN DIFFERENT APPLE GROWING TECHNOLOGIES

    OpenAIRE

    Venera TASSEVA

    2005-01-01

    The investigation was carried out in the period 2001-2003 in an orchard of the Institute of Agriculture, Kyustendil, Bulgaria, created in the spring of 1996 on leached cinnamonic forest soil. The weed populations under four different farming technologies of growing of apple cultivar Florina were investigated. It was established, that the apple growing technologies influence the weed association composition. The highest weed diversity was found in the organic technology - 16 weed species were ...

  1. Vegetation diversity of the Scots pine stands in different forest sites in the Turawa Forest District

    OpenAIRE

    Stefa?ska-Krzaczek, Ewa; Pech, Pawe?

    2014-01-01

    The utility of phytocenotic indices in the diagnosis and classification of forest sites might be limited because of vegetation degeneration in managed forests. However, even in secondary communities it may be possible to determine indicator species, although these may differ from typical and well known plant indicators. The aim of this work was to assess the vegetation diversity of Scots pine stands in representative forest site types along a moisture and fertility gradient. In total ...

  2. Phenolic profile evolution of different ready-to-eat baby-leaf vegetables during storage

    OpenAIRE

    Santos, Joana; Oliveira, M.B.P.P.; Ibáñez, Elena; Herrero, Miguel

    2014-01-01

    Ready-to-eat baby-leaf vegetables market has been growing and offering to consumers convenient, healthy and appealing products, which may contain interesting bioactive compounds. In this work, the composition and the evolution of the phenolic compounds from different baby-leaf vegetables during refrigerated storage was studied. The phenolic compounds were extracted using pressurized liquid extraction (PLE) and the phenolic profile of each sample was analyzed and quantified by using LC-MS and ...

  3. Phytonutrient intakes in relation to European fruit and vegetable consumption patterns observed in different food surveys

    OpenAIRE

    Tennant, David R.; Davidson, Julia; Day, Andrea J.

    2014-01-01

    Fruit and vegetables make an important contribution to health, partly due to the composition of phytonutrients, such as carotenoids and polyphenols. The aim of the present study was to quantify the intake of fruit and vegetables across different European countries using food consumption data of increasing complexity: food balance sheets (FBS); the European Food Safety Authority (EFSA) Comprehensive Database; individual food consumption data from the UK National Diet and Nutrition Survey (NDNS...

  4. Variation of MODIS reflectance and vegetation indices with viewing geometry and soybean development

    OpenAIRE

    Fábio M. Breunig; Lênio S. Galvão; Antônio R. Formaggio; JOSÉ C.N. EPIPHANIO

    2012-01-01

    Directional effects introduce a variability in reflectance and vegetation index determination, especially when large field-of-view sensors are used (e.g., Moderate Resolution Imaging Spectroradiometer - MODIS). In this study, we evaluated directional effects on MODIS reflectance and four vegetation indices (Normalized Difference Vegetation Index - NDVI; Enhanced Vegetation Index - EVI; Normalized Difference Water Index - NDWI1640 and NDWI2120) with the soybean development in two growing seaso...

  5. Índices de área verde e cobertura vegetal para as praças do Municipio de Vinhedo, SP Green area and vegetation cover indexes for commos in the city of Vinhedo, SP

    Directory of Open Access Journals (Sweden)

    Isabel Cristina Fialho Harder

    2006-04-01

    Full Text Available Neste estudo, objetivou-se a obtenção, para o Município de Vinhedo (SP, de índices que auxiliem a indicação da ocupação dos espaços urbanos pela vegetação. Foi realizado o levantamento das praças localizadas dentro dos bairros e das árvores (altura, diâmetro da copa e circunferência à altura do peito contidas nessas praças. Os índices de área verde calculados foram: Índice de Áreas Verdes Total (IAVT, Índice de Áreas Verdes para Parque da Vizinhança (IAVPV, Índice de Áreas Verdes para Parque de Bairro (IAVPB, Índice de Áreas Verdes Utilizáveis (IAVU, Índice de Área Verde por Bairro (AVB e Índice de Cobertura Vegetal (ICV. O Município de Vinhedo apresentou pouca variação entre os índices IAVT = 2,19 m² e IAVU = 1,95 m², indicando que a maioria das áreas verdes era utilizável. O IAVT de Vinhedo estava abaixo do mínimo de 15 m²/habitante para áreas verdes públicas destinadas à recreação, sugerido pela Sociedade Brasileira de Arborização Urbana.This research was carried out to study, in the city of Vinhedo (SP, indexes that indicate the vegetation occupation in urban spaces. Data were collected by locating the commons in the neighborhoods and the tree measures (height, diameter and circumference at breast height, in those commons. The calculated indexes were Total Green Area Index (IAVT, Green Area Index for Near Neighborhood Park (IAVPV, Green Area Index for Neighborhood Park (IAPVPB, Usable Green Area Index (IAVU, Green Area Index for Neighborhoods (AVB and Vegetation Cover Index (ICV. The city of Vinhedo showed few variation between the indexes IAVT = 2.19 m² and IAVU = 1.95 m² indicating that most of the green areas are usable. Vinhedo's IAVT is below the minimum of 15m²/inhabitant for public recreation in green areas, suggested by the Brazilian Society for Urban Forestation.

  6. Why are there different versions of the Oswestry Disability Index?

    Science.gov (United States)

    Fairbank, Jeremy C T

    2014-01-01

    This article updates readers on the current state of the Oswestry Disability Index (ODI) and the impact of unvalidated versions. The ODI is now licensed to the Mapi Research Trust in order to preserve a standard version in English and in validated translations. A proposed threshold of "normality" is potentially helpful as an outcome for both audit and research. There is an application of the sex section as a quality measure in Germany. The ODI is an important international shared resource for clinicians and investigators and should not be abused. Its current status will not be enhanced by further modification. It is now registered with the International Consortium for Health Outcomes Measurement as a standard outcome measure. PMID:24206036

  7. The Normalized Difference Infrared Index (NDII) as a proxy for soil moisture storage in hydrological modelling

    Science.gov (United States)

    Sriwongsitanon, N.; Gao, H.; Savenije, H. H. G.; Maekan, E.; Saengsawang, S.; Thianpopirug, S.

    2015-08-01

    With remote sensing we can readily observe the Earth's surface, but looking under the surface into the root zone of vegetation is still a major challenge. Yet knowledge on the dynamics of soil moisture in the root zone is essential for agriculture, land-atmosphere interaction and hydrological modelling, alike. In this paper we develop a novel approach to monitor the soil moisture storage deficit in the root zone of vegetation, by using the remotely sensed Normalised Difference Infrared Index (NDII) in the Upper Ping River Basin (UPRB) in northern Thailand. Satellite data from the Moderate Resolution Imaging Spectro-radiometer (MODIS) was used to evaluate the NDII over an 8 day period, covering the study area from 2001 to 2013. The results show that NDII values decrease sharply at the end of the wet season in October and reach lowest values near the end of the dry season in March. The values then increase abruptly after rains have started, but vary in an insignificant manner from the middle to the late rainy season. The NDII proves to be a very strong proxy for moisture storage deficit in the root zone, which is a crucial component of hydrological models. In addition, the NDII appears to be a reliable indicator for the temporal and spatial distribution of drought conditions in the UPRB. The 8 day average NDII values were found to correlate very well with the 8 day average soil moisture content (SU) simulated by FLEXL (rainfall-runoff model) at 8 runoff stations during the dry season - giving an average R2 value 0.87 on an exponential relationship, while for the wet season it reduced to be around 0.61. Apparently, the NDII is an effective index for the moisture storage in the root zone during the time of moisture deficit, and a powerful indicator to assess droughts. In the dry season, when plants are exposed to water stress, the leaf-water deficit increases steadily. Once leaf-water is close to saturation - mostly at the end of the wet season - leaf characteristics and NDII values do not vary significantly, causing lower correlation between NDII and Su in the wet season. However, the correlations between NDII and Su still remain high for both seasons and therefore the product can be used to define drought situations throughout the year and be of use to water management.

  8. SPECIES COMPOSITION OF WEED VEGETATION IN DIFFERENT APPLE GROWING TECHNOLOGIES

    Directory of Open Access Journals (Sweden)

    Venera TASSEVA

    2005-08-01

    Full Text Available The investigation was carried out in the period 2001-2003 in an orchard of the Institute of Agriculture, Kyustendil, Bulgaria, created in the spring of 1996 on leached cinnamonic forest soil. The weed populations under four different farming technologies of growing of apple cultivar Florina were investigated. It was established, that the apple growing technologies influence the weed association composition. The highest weed diversity was found in the organic technology - 16 weed species were found. In the application of resource economical and integrated technologies, the development of 13-14 weed species was established. The smallest weed diversity was observed in the conventional technology - eight species, which was due to the twofold herbicide application.

  9. [Comparison of soil fertility among open-pit mine reclaimed lands in Antaibao regenerated with different vegetation types].

    Science.gov (United States)

    Wang, Xiang; Li, Jin-chuan; Yue, Jian-ying; Zhou, Xiao-mei; Guo, Chun-yan; Lu, Ning; Wang, Yu-hong; Yang, Sheng-quan

    2013-09-01

    Re-vegetation is mainly applied into regeneration in opencast mine to improve the soil quality. It is very important to choose feasible vegetation types for soil restoration. In this study, three typical forest restoration types were studied at Antaibao mine, namely, Medicago sativa, mixed forests Pinus taebelaefolius-Robinia pseudoacacia-Caragana korshinskii and Elaeagnus angustifolia-Robinia pseudoacacia-Caragana korshinskii-Hipophae rhamnoides, to determine the nutrient contents and enzyme activities in different soil layers. The results showed that re-vegetation markedly increased soil nutrient contents and the enzyme activities during the restoration process. The nutrient content of soil in the P. taebelaefolius-R. pseudoacacia-C. korshinskii mixed forest field was significantly higher than those in other plots. It was found that the soil of the P. taebelaefolius-R. pseudoacacia-C. korshinskii mixed forest had the highest integrated fertility index values. In conclusion, the restoration effects of the P. zaebelaefolius-R. pseudoacacia-C. Korshinskii mixed forest was better than that of E. angustifolia-R. pseudoacacia-C. korshinskii-H. rhamnoides, while M. sativa grassland had the least effect. PMID:24289011

  10. Interannual variations and trends in global land surface phenology derived from enhanced vegetation index during 1982-2010

    Science.gov (United States)

    Zhang, Xiaoyang; Tan, Bin; Yu, Yunyue

    2014-05-01

    Land surface phenology is widely retrieved from satellite observations at regional and global scales, and its long-term record has been demonstrated to be a valuable tool for reconstructing past climate variations, monitoring the dynamics of terrestrial ecosystems in response to climate impacts, and predicting biological responses to future climate scenarios. This study detected global land surface phenology from the advanced very high resolution radiometer (AVHRR) and the Moderate Resolution Imaging Spectroradiometer (MODIS) data from 1982 to 2010. Based on daily enhanced vegetation index at a spatial resolution of 0.05 degrees, we simulated the seasonal vegetative trajectory for each individual pixel using piecewise logistic models, which was then used to detect the onset of greenness increase (OGI) and the length of vegetation growing season (GSL). Further, both overall interannual variations and pixel-based trends were examined across Koeppen's climate regions for the periods of 1982-1999 and 2000-2010, respectively. The results show that OGI and GSL varied considerably during 1982-2010 across the globe. Generally, the interannual variation could be more than a month in precipitation-controlled tropical and dry climates while it was mainly less than 15 days in temperature-controlled temperate, cold, and polar climates. OGI, overall, shifted early, and GSL was prolonged from 1982 to 2010 in most climate regions in North America and Asia while the consistently significant trends only occurred in cold climate and polar climate in North America. The overall trends in Europe were generally insignificant. Over South America, late OGI was consistent (particularly from 1982 to 1999) while either positive or negative GSL trends in a climate region were mostly reversed between the periods of 1982-1999 and 2000-2010. In the Northern Hemisphere of Africa, OGI trends were mostly insignificant, but prolonged GSL was evident over individual climate regions during the last 3 decades. OGI mainly showed late trends in the Southern Hemisphere of Africa while GSL was reversed from reduced GSL trends (1982-1999) to prolonged trends (2000-2010). In Australia, GSL exhibited considerable interannual variation, but the consistent trend lacked presence in most regions. Finally, the proportion of pixels with significant trends was less than 1 % in most of climate regions although it could be as large as 10 %.

  11. Índice de vegetação do sensor MODIS na estimativa da produtividade agrícola da cana-de-açúcar Vegetation index from MODIS sensor to estimate sugarcane yield

    Directory of Open Access Journals (Sweden)

    Michelle Cristina Araujo Picoli

    2009-09-01

    Full Text Available A participação da cultura da cana-de-açúcar no fornecimento de matéria prima para produção de açúcar e também de álcool, como fonte alternativa de energia, tem sido relevante para o crescimento econômico do Brasil. Consequentemente, a disponibilidade de informações precisas sobre a produção agrícola dessa cultura é importante para auxiliar no planejamento e na tomada de decisões em toda a cadeia produtiva. O presente trabalho teve como objetivo estimar a produtividade agrícola de talhões de cana-de-açúcar para as safras 2004/2005 e 2005/2006, a partir de um modelo agronômico ajustado com dados orbitais. A inovação deste modelo consiste no uso do índice de área foliar (IAF estimado a partir do produto índice de vegetação NDVI (Normalized Difference Vegetation Index do sensor MODIS (Moderate Resolution Imaging Spectroradiometer a bordo do satélite Terra da NASA (National Aeronautics Space Administration. O modelo agronômico explicou 31% e 25% da variação da produtividade observada entre talhões nos anos safra 2004/2005 e 2005/2006, respectivamente, o que se deve fundamentalmente ao uso das imagens NDVI do MODIS. O resultado do modelo pode ser usado para auxiliar e aprimorar a previsão da estimativa da produtividade feita in loco.The contribution of sugarcane crop to provide raw material to produce sugar and also alcohol as an alternative energy source has been relevant to the economic growth of Brazil. Therefore, the availability of precise agricultural production information about this crop is important for planning and decision-making in the entire productive chain. The present work has the objective to estimate sugarcane yield in crop fields during the crop years 2004/2005 and 2005/2006, based on an agronomic model fit with orbital data. The innovation of this model consists in the use of the leaf area index (LAI estimated from the NDVI (Normalized Difference Vegetation Index produced by the MODIS sensor (Moderate Resolution Imaging Spectroradiometer on board of the Terra satellite from NASA (National Aeronautics Space Administration. The agronomic model explained 31% and 25% of the yield variability among crop fields for the crop years 2004/2005 and 2005/2006, respectively, which is mainly attributed to use of NDVI images from MODIS. The model output should be useful to improve the precision of the crop yield estimation forecast performed in loco.

  12. Índice de vegetação do sensor MODIS na estimativa da produtividade agrícola da cana-de-açúcar / Vegetation index from MODIS sensor to estimate sugarcane yield

    Scientific Electronic Library Online (English)

    Michelle Cristina Araujo, Picoli; Bernardo Friedrich Theodor, Rudorff; Rodrigo, Rizzi; Angélica, Giarolla.

    2009-09-01

    Full Text Available A participação da cultura da cana-de-açúcar no fornecimento de matéria prima para produção de açúcar e também de álcool, como fonte alternativa de energia, tem sido relevante para o crescimento econômico do Brasil. Consequentemente, a disponibilidade de informações precisas sobre a produção agrícola [...] dessa cultura é importante para auxiliar no planejamento e na tomada de decisões em toda a cadeia produtiva. O presente trabalho teve como objetivo estimar a produtividade agrícola de talhões de cana-de-açúcar para as safras 2004/2005 e 2005/2006, a partir de um modelo agronômico ajustado com dados orbitais. A inovação deste modelo consiste no uso do índice de área foliar (IAF) estimado a partir do produto índice de vegetação NDVI (Normalized Difference Vegetation Index) do sensor MODIS (Moderate Resolution Imaging Spectroradiometer) a bordo do satélite Terra da NASA (National Aeronautics Space Administration). O modelo agronômico explicou 31% e 25% da variação da produtividade observada entre talhões nos anos safra 2004/2005 e 2005/2006, respectivamente, o que se deve fundamentalmente ao uso das imagens NDVI do MODIS. O resultado do modelo pode ser usado para auxiliar e aprimorar a previsão da estimativa da produtividade feita in loco. Abstract in english The contribution of sugarcane crop to provide raw material to produce sugar and also alcohol as an alternative energy source has been relevant to the economic growth of Brazil. Therefore, the availability of precise agricultural production information about this crop is important for planning and de [...] cision-making in the entire productive chain. The present work has the objective to estimate sugarcane yield in crop fields during the crop years 2004/2005 and 2005/2006, based on an agronomic model fit with orbital data. The innovation of this model consists in the use of the leaf area index (LAI) estimated from the NDVI (Normalized Difference Vegetation Index) produced by the MODIS sensor (Moderate Resolution Imaging Spectroradiometer) on board of the Terra satellite from NASA (National Aeronautics Space Administration). The agronomic model explained 31% and 25% of the yield variability among crop fields for the crop years 2004/2005 and 2005/2006, respectively, which is mainly attributed to use of NDVI images from MODIS. The model output should be useful to improve the precision of the crop yield estimation forecast performed in loco.

  13. [Comparison and analysis of hyperspectral remote sensing identifiable models for different vegetation under waterlogging stress].

    Science.gov (United States)

    Jiang, Jin-Bao; Steven, Michael D; He, Ru-Yan; Cai, Qing-Kong

    2013-11-01

    With the global climate warming, flooding disasters frequently occurred and its influence scope constantly increased in China. The objective of the present paper was to study the leaf spectral features of vegetation (maize and beetroot) under waterlogging stress and design a hyperspectral remote sensing model to monitor the flooding disasters through a field simulated experiment. The experiment was carried out in the Sutton Bonington Campus of University of Nottingham (52.8 degrees N, 1. 2 degrees W) from May to August in 2008, and samples were collected one time every week and spectra were measured in the laboratory. The result showed that the reflectance of the maize and beetroot decreased in the 550 and 800-1 300 nm region, and the reflectance slightly increased in the 680 nm region. This paper chose NDVI, SIPI, PRI, SRPI, GNDVI and R800 * R550/R680 to identify the vegetation under waterlogging stress, respectively. The result suggested that the SIPI and R800 * R550/R680 was sensitive for maize under waterlogging stress, and then SIPI and PRI and R800 * R550/R680 was sensitive for beetroot under waterlogging stress. In order to seek the best identifiable model, the normalized distances between means of control and stressed vegetation indices were calculated and analyzed, the result indicated that the distance of R800 * R550/R680 is more than that of indices' in the early stress stage, illustrated that the index identifiable ability for waterlogging stress is better than other indices, then the index has the strong sensitivity and stability. Therefore, the index R800 * R550/R680 could be used to quickly extract flooding disaster area by using hyperspectral remote sensing, and would provide information support for disaster relief decisions. PMID:24555391

  14. A Method for Application of Classification Tree Models to Map Aquatic Vegetation Using Remotely Sensed Images from Different Sensors and Dates

    Directory of Open Access Journals (Sweden)

    Ying Cai

    2012-09-01

    Full Text Available In previous attempts to identify aquatic vegetation from remotely-sensed images using classification trees (CT, the images used to apply CT models to different times or locations necessarily originated from the same satellite sensor as that from which the original images used in model development came, greatly limiting the application of CT. We have developed an effective normalization method to improve the robustness of CT models when applied to images originating from different sensors and dates. A total of 965 ground-truth samples of aquatic vegetation types were obtained in 2009 and 2010 in Taihu Lake, China. Using relevant spectral indices (SI as classifiers, we manually developed a stable CT model structure and then applied a standard CT algorithm to obtain quantitative (optimal thresholds from 2009 ground-truth data and images from Landsat7-ETM+, HJ-1B-CCD, Landsat5-TM and ALOS-AVNIR-2 sensors. Optimal CT thresholds produced average classification accuracies of 78.1%, 84.7% and 74.0% for emergent vegetation, floating-leaf vegetation and submerged vegetation, respectively. However, the optimal CT thresholds for different sensor images differed from each other, with an average relative variation (RV of 6.40%. We developed and evaluated three new approaches to normalizing the images. The best-performing method (Method of 0.1% index scaling normalized the SI images using tailored percentages of extreme pixel values. Using the images normalized by Method of 0.1% index scaling, CT models for a particular sensor in which thresholds were replaced by those from the models developed for images originating from other sensors provided average classification accuracies of 76.0%, 82.8% and 68.9% for emergent vegetation, floating-leaf vegetation and submerged vegetation, respectively. Applying the CT models developed for normalized 2009 images to 2010 images resulted in high classification (78.0%–93.3% and overall (92.0%–93.1% accuracies. Our results suggest that Method of 0.1% index scaling provides a feasible way to apply CT models directly to images from sensors or time periods that differ from those of the images used to develop the original models.

  15. Internalisation of Microbes in Vegetables: Microbial Load of Ghanaian Vegetables and the Relationship with Different Water Sources of Irrigation

    OpenAIRE

    Jonathan Quaye; Kayang, Boniface B.; R. Lanyo; Eric S. Donkor; Edoh, Dominic A.

    2010-01-01

    The occurrence of pathogens in the internal parts of vegetables is usually associated with irrigation water or contaminated soil and could pose risk to consumers as the internalised pathogens are unaffected by external washing. This study was carried out to assess the rate of internalisation of microbes in common Ghanaian vegetables. Standard microbiological methods were employed in microbial enumeration of vegetables collected at the market and farm levels, as well as irrigation water and so...

  16. Mapping paddy rice planting areas through time series analysis of MODIS land surface temperature and vegetation index data

    Science.gov (United States)

    Zhang, Geli; Xiao, Xiangming; Dong, Jinwei; Kou, Weili; Jin, Cui; Qin, Yuanwei; Zhou, Yuting; Wang, Jie; Menarguez, Michael Angelo; Biradar, Chandrashekhar

    2015-08-01

    Knowledge of the area and spatial distribution of paddy rice is important for assessment of food security, management of water resources, and estimation of greenhouse gas (methane) emissions. Paddy rice agriculture has expanded rapidly in northeastern China in the last decade, but there are no updated maps of paddy rice fields in the region. Existing algorithms for identifying paddy rice fields are based on the unique physical features of paddy rice during the flooding and transplanting phases and use vegetation indices that are sensitive to the dynamics of the canopy and surface water content. However, the flooding phenomena in high latitude area could also be from spring snowmelt flooding. We used land surface temperature (LST) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor to determine the temporal window of flooding and rice transplantation over a year to improve the existing phenology-based approach. Other land cover types (e.g., evergreen vegetation, permanent water bodies, and sparse vegetation) with potential influences on paddy rice identification were removed (masked out) due to their different temporal profiles. The accuracy assessment using high-resolution images showed that the resultant MODIS-derived paddy rice map of northeastern China in 2010 had a high accuracy (producer and user accuracies of 92% and 96%, respectively). The MODIS-based map also had a comparable accuracy to the 2010 Landsat-based National Land Cover Dataset (NLCD) of China in terms of both area and spatial pattern. This study demonstrated that our improved algorithm by using both thermal and optical MODIS data, provides a robust, simple and automated approach to identify and map paddy rice fields in temperate and cold temperate zones, the northern frontier of rice planting.

  17. Leaf area index estimation in different crops: Case study for wheat, maize, soybean, and potato

    Science.gov (United States)

    Gitelson, A. A.; Nguy-Robertson, A. L.; Peng, Y.; Arkebauer, T. J.; Pimstein, A.; Herrmann, I.; Karnieli, A.; Rundquist, D. C.; Bonfil, D.

    2012-12-01

    Vegetation indices (VIs) have been shown to be a proxy of green leaf area index (gLAI); however, it has not been verified whether the relationships VI vs. gLAI are the same, as well as VIs retaining their accuracy, for various crop types for estimating gLAI. The goal of this study was to (1) determine if the best VIs used in previous studies for gLAI estimation in maize and soybean may be applicable for potato and wheat and vice versa, and (2) determining the cause of a hysteresis between green up and reproductive stages for the VI vs. gLAI relationship. Spectral measurements of wheat and potato were obtained in Israel and of maize and soybean in the USA. In Israel, remote estimates of gLAI were compared with in-situ canopy transmittance measurements of irrigated potato and wheat under various nitrogen treatments from 2004-2007 for a total of 15 field-years. In eastern Nebraska, USA, remote estimates of maize and soybean gLAI data were compared with destructive gLAI determination in two irrigated/rainfed maize/soybean rotation sites and in one irrigated site under continuous maize. These data were collected during eight years (2001-2008) for a total of 24 field-years. For all four crops, the ten VIs examined showed similarities in relationships between VIs and gLAI with the exception of Red-edge Inflection Point (REIP) and the MERIS Terrestrial Chlorophyll Index (MTCI). REIP and MTCI have very different relationships with maize and soybean gLAI in green up and reproductive stages, thus, they require re-parameterization during the season. This study outlines the two major factors that influence the VI vs. gLAI relationship in the green up and reproductive stages. While the results suggest that relationships VI vs. gLAI are quite close for all four crops, different methodologies in determining the ground-truth measurements of gLAI prevent us to confirm whether algorithms calibrated for one crop can be used with no re-parameterization for other crops. These concerns aside, we found that normalized difference VIs (NDVI, Green NDVI, etc.) were capable of estimating accurately gLAI below 2 and ratio VIs (Simple Ratio, CIgreen, etc.) were best for gLAI above 2. For all four crops, green and red-edge chlorophyll indices appear to be the most accurate for gLAI estimation.

  18. Modeling the effects of vegetation on methane oxidation and emissions through soil landfill final covers across different climates.

    Science.gov (United States)

    Abichou, Tarek; Kormi, Tarek; Yuan, Lei; Johnson, Terry; Francisco, Escobar

    2015-02-01

    Plant roots are reported to enhance the aeration of soil by creating secondary macropores which improve the diffusion of oxygen into soil as well as the supply of methane to bacteria. Therefore, methane oxidation can be improved considerably by the soil structuring processes of vegetation, along with the increase of organic biomass in the soil associated with plant roots. This study consisted of using a numerical model that combines flow of water and heat with gas transport and oxidation in soils, to simulate methane emission and oxidation through simulated vegetated and non-vegetated landfill covers under different climatic conditions. Different simulations were performed using different methane loading flux (5-200 g m(-2) d(-1)) as the bottom boundary. The lowest modeled surface emissions were always obtained with vegetated soil covers for all simulated climates. The largest differences in simulated surface emissions between the vegetated and non-vegetated scenarios occur during the growing season. Higher average yearly percent oxidation was obtained in simulations with vegetated soil covers as compared to non-vegetated scenario. The modeled effects of vegetation on methane surface emissions and percent oxidation were attributed to two separate mechanisms: (1) increase in methane oxidation associated with the change of the physical properties of the upper vegetative layer and (2) increase in organic matter associated with vegetated soil layers. Finally, correlations between percent oxidation and methane loading into simulated vegetated and non-vegetated covers were proposed to allow decision makers to compare vegetated versus non-vegetated soil landfill covers. These results were obtained using a modeling study with several simplifying assumptions that do not capture the complexities of vegetated soils under field conditions. PMID:25475118

  19. Description of psychophysiological indexes of students of different sporting specializations

    Directory of Open Access Journals (Sweden)

    Barybina L.N.

    2010-08-01

    Full Text Available Information of the psychophysiological testing of students of technical institute of higher of different sporting specializations is considered. In research took part 159 students of specialization football, sambo, volleyball, basketball, aerobics, boxing, heavy athletics. The psychophysiological testing is given by possibility to choose the proper sporting specialization students for the best realization of the personality qualities. Positive attitude of students is marked toward employments on physical education. The increase of self-appraisal and improvement of health of students is also marked.

  20. Internalisation of Microbes in Vegetables: Microbial Load of Ghanaian Vegetables and the Relationship with Different Water Sources of Irrigation

    Directory of Open Access Journals (Sweden)

    Jonathan Quaye

    2010-01-01

    Full Text Available The occurrence of pathogens in the internal parts of vegetables is usually associated with irrigation water or contaminated soil and could pose risk to consumers as the internalised pathogens are unaffected by external washing. This study was carried out to assess the rate of internalisation of microbes in common Ghanaian vegetables. Standard microbiological methods were employed in microbial enumeration of vegetables collected at the market and farm levels, as well as irrigation water and soil samples. The overall mean counts of vegetables were 4.0x103 cfu g-1; 8.1x102 cfu g-1; 2.0x102 cfu g-1; 3.5x102 cfu g-1 for total bacteria, coliform counts, faecal coliform counts and yeast counts, respectively. The rate of internalisation of coliforms in vegetables irrigated with stream/well water was 2.7 times higher than those irrigated with pipe water. The mean coliform counts (4.7x107 cfu g-1 and faecal coliform counts (1.8x106 cfu g-1 of soil samples were similar to those of stream water suggesting both sources exerted similar contamination rates on the vegetables. Generally, there were no significant variations between the rates of internalisation of microbes at the market and farm levels at p<05, indicating that internalisation of microbes in the vegetables mainly occurred at the farm level. The study has shown that microbial contamination of vegetables in Ghana is not limited to the external surface, but internal vegetable parts could harbour high microbial loads and pose risk to consumers. Safety practices associated with the commodity should therefore not be limited to external washing only. There is the additional need of heating vegetables to eliminate microbes both externally and internally before consumption.

  1. Theory of Planned Behavior Explains Gender Difference in Fruit and Vegetable Consumption

    OpenAIRE

    Emanuel, Amber S.; McCully, Scout N; Gallagher, Kristel M.; Updegraff, John A.

    2012-01-01

    A gender difference in fruit and vegetable intake (FVI) is widely documented, but not well understood. Using data from the National Cancer Institute’s Food Attitudes and Behavior Survey, we assessed the extent to which gender differences in FVI are attributable to gender differences in constructs from the Theory of Planned Behavior (TPB). Females reported more favorable attitudes and greater perceived behavior control regarding FVI than males, and these beliefs mediated the observed gender di...

  2. Differences of fire activity and their underlying factors among vegetation formations in Greece

    OpenAIRE

    Xystrakis F; Koutsias N

    2013-01-01

    Climate and weather play an important role in shaping fire activity patterns by controlling fuel productivity and fire spread, respectively. Additionally, climate is a key factor controlling primary productivity while different climate zones are expected to support different vegetation formations, that on their turn, include different fuel types. The use, therefore, of an underlying phytogeographical framework would provide more comprehensive outputs in exploring fire activity patterns at nat...

  3. Applications of an innovative technique for histological and histo-chemical study of different vegetal tissues

    OpenAIRE

    DORE, Bruno Emilio

    2006-01-01

    A new original "cryostabilization" technique, based on frezing and contemporaneous substitution in Ethylene Glycol, at -20°C, followed by Glicol Methacrylate (GMA) embedding at low temperature (6-10°C), was applied to different vegetal tissues and organs: ripening and ripe fleshy fruits of apples, grapes, grapefruits, apricot, kiwi, cherries, tomatoes, buds and embryos.

  4. Mitigation of heavy metals in different vegetables through biological washing techniques

    Directory of Open Access Journals (Sweden)

    Muhammad Umair Sattar

    2015-12-01

    Full Text Available Availability of nutritious and healthy food is the foremost challenging issue in all over the word. Vegetables are essential part in human diet and considered as natural reserves of nutrients gifted by Almighty Allah to human beings. Heavy metals are among the most toxic food pollutants and their intake through diet leads to several disorders. The sources of heavy metal contamination include waste water irrigation, industrial emissions, transportation and application of metal-based pesticides. In Pakistan this situation is more alarming as vegetables grown in peri-urban areas have shown high incidence of heavy metals accumulation. In this study effort was made to mitigate different heavy metals (Ar, Cd, Cr and Pb in cauliflower, spinach, okra and brinjal collected from peri-urban areas through washing with different biological solutions. Heavy metals contents were determined by using Atomic Absorption Spectrophotometry (AAS. Vegetable showed high load of heavy metals in unwashed form that reduced significantly by washing with different biological solutions. Among the different biological solutions, washing of vegetables with 8% ginger solution was found to be more effective.

  5. Evaluation of Extraction Methods for the Analysis of Carotenoids for Different Vegetable Matrix

    Directory of Open Access Journals (Sweden)

    Stancuta Scrob

    2013-11-01

    Full Text Available In this study, different solvents were used to achieve the maximum extractibility of total carotenoids. The extracted total carotenoids were estimated using UV- visible spectrophotometer. Carotenoids from vegetable matrix can be used as a food colorant, food additive, cosmetics, antioxidants and nutraceuticals.

  6. Evaluation of Extraction Methods for the Analysis of Carotenoids for Different Vegetable Matrix

    OpenAIRE

    Stancuta Scrob; Sevastita Muste; Crina Muresan; Anca Farcas; Sonia Socaci; Romina Vlaic

    2013-01-01

    In this study, different solvents were used to achieve the maximum extractibility of total carotenoids. The extracted total carotenoids were estimated using UV- visible spectrophotometer. Carotenoids from vegetable matrix can be used as a food colorant, food additive, cosmetics, antioxidants and nutraceuticals.

  7. Response of vegetable organisms to quasi-monochromatic light of different duration, intensity and wavelength

    Science.gov (United States)

    Budagovsky, A. V.; Solovykh, N. V.; Budagovskaya, O. N.; Budagovsky, I. A.

    2015-04-01

    By the example of vegetable organisms differing in structure and functional properties it is shown that their response to the action of quasi-monochromatic light from laser sources does not obey the Bunsen - Roscoe dose law. The dependence of biological effect on the irradiation time has the multimodal (multiextremal) form with alternating maxima and minima of the stimulating effect. Such a property manifests itself in the spectral ranges, corresponding to photoinduced conversion of chromoproteins of photocontrol systems and is probably related to the cyclic variations of metabolic activity in vegetable cells.

  8. Effects of Different Cooking Methods on Improving Total Antioxidant Activity in Selected Vegetables

    Directory of Open Access Journals (Sweden)

    Wei-Hua Xie

    2015-08-01

    Full Text Available The present study compares Water-soluble Phenolic Content (WPC and antioxidant activities in eggplant, kidney bean, bitter gourd and spinachprior to and after subjecting to boiling, microwaving and pressure cooking. The total antioxidant activity was increased in cooked spinach, eggplant and bitter gourd, estimated based on the ferric reducing antioxidant power, the Troloxequivalent antioxidant capacity and 2, 2-diphenyl-1-picryl-hydrazyl radical scavenging activity. Pressure cooking did not cause any significant decline in the antioxidant property. Boiling generally improved the overall antioxidant activity in all the vegetables. Correlation analysis suggests that WPC contributed to significant antioxidant activities in these vegetables. Thus, prudence in selecting an appropriate cooking method for different vegetables may improve or preserve their nutritional value.

  9. The Effectiveness of Web Search Engines to Index New Sites from Different Countries

    Science.gov (United States)

    Pirkola, Ari

    2009-01-01

    Introduction: Investigates how effectively Web search engines index new sites from different countries. The primary interest is whether new sites are indexed equally or whether search engines are biased towards certain countries. If major search engines show biased coverage it can be considered a significant economic and political problem because…

  10. Index

    Directory of Open Access Journals (Sweden)

    Antonio Juan Sánchez

    2012-09-01

    Full Text Available The Advances in Distributed Computing and Artificial Intelligence Journal (ISSN: 2255-2863 is an open access journal that publishes articles which contribute new results associated with distributed computing and artificial intelligence, and their application in different areas. The artificial intelligence is changing our society. Its application in distributed environments, such as the Internet, electronic commerce, mobile communications, wireless devices, distributed computing and so on, is increasing and becoming and element of high added value and economic potential in industry and research. These technologies are changing constantly as a result of the large research and technical effort being undertaken in both universities and businesses. The exchange of ideas between scientists and technicians from both academic and business areas is essential to facilitate the development of systems that meet the demands of today's society.

  11. [Progress in retrieving vegetation water content under different vegetation coverage condition based on remote sensing spectral information].

    Science.gov (United States)

    Zhang, Jia-Hua; Li, Li; Yao, Feng-Mei

    2010-06-01

    The present paper reviews the progress in the methods of retrieving vegetation water content using remote sensing spectral information, including vegetation spectral reflectance information (VIR, SWIR, and NIR) to directly extract vegetation water content and establish vegetation water indices (WI), i. e. NDWI = (R860 - R1 240)/(R860 + R1 240) and PWI = R970/R900; and using radiation transfer (RT) model such as PROSPAIL to detect plant water content information. The authors analyze the method of retrieving vegetation water content under low crop coverage condition. The plant water can be estimated by using canopy physiological parameters firstly, and using vegetation indices and radiation transfer model secondly, which can eliminate soil background effect. The estimated agricultural drought and vegetation water content by using multi-angle polarized reflectance and bi-directional reflectance (BRDF) was discussed in this paper. In the end, the possible development trend of retrieval methods for plant water information under plant low coverage conditions was discussed. PMID:20707166

  12. Application of Advanced Very High Resolution Radiometer vegetation index to study atmosphere-biosphere exchange of CO2

    Science.gov (United States)

    Fung, I. Y.; Tucker, C. J.; Prentice, K. C.

    1987-01-01

    Normalized difference vegetation indices derived from radiances measured by the Advanced Very High Resolution Radiometer were used to prescribe the phasing of terrestrial photosynthesis. The satellite data were combined with field data on soil respiration and a global map of net primary productivity to obtain the seasonal exchange of CO2 between the atmosphere and the terrestrial biosphere. The monthly fluxes of CO2 thus obtained were employed as source/sink functions in a global three-dimensional atmospheric tracer transport model to simulate the annual oscillations of CO2 in the atmosphere. The results demonstrate that satellite data of high spatial and temporal resolution can be used to provide quantitative information about seasonal and longer-term variations of photosynthetic activity on a global scale.

  13. Estimates of evapotranspiration for riparian sites (Eucalyptus) in the Lower Murray -Darling Basin using ground validated sap flow and vegetation index scaling techniques

    Science.gov (United States)

    Doody, T.; Nagler, P. L.; Glenn, E. P.

    2014-12-01

    Water accounting is becoming critical globally, and balancing consumptive water demands with environmental water requirements is especially difficult in in arid and semi-arid regions. Within the Murray-Darling Basin (MDB) in Australia, riparian water use has not been assessed across broad scales. This study therefore aimed to apply and validate an existing U.S. riparian ecosystem evapotranspiration (ET) algorithm for the MDB river systems to assist water resource managers to quantify environmental water needs over wide ranges of niche conditions. Ground-based sap flow ET was correlated with remotely sensed predictions of ET, to provide a method to scale annual rates of water consumption by riparian vegetation over entire irrigation districts. Sap flux was measured at nine locations on the Murrumbidgee River between July 2011 and June 2012. Remotely sensed ET was calculated using a combination of local meteorological estimates of potential ET (ETo) and rainfall and MODIS Enhanced Vegetation Index (EVI) from selected 250 m resolution pixels. The sap flow data correlated well with MODIS EVI. Sap flow ranged from 0.81 mm/day to 3.60 mm/day and corresponded to a MODIS-based ET range of 1.43 mm/day to 2.42 mm/day. We found that mean ET across sites could be predicted by EVI-ETo methods with a standard error of about 20% across sites, but that ET at any given site could vary much more due to differences in aquifer and soil properties among sites. Water use was within range of that expected. We conclude that our algorithm developed for US arid land crops and riparian plants is applicable to this region of Australia. Future work includes the development of an adjusted algorithm using these sap flow validated results.

  14. Index

    Directory of Open Access Journals (Sweden)

    Antonio Juan SÁNCHEZ

    2013-05-01

    Full Text Available The Advances in Distributed Computing and Artificial Intelligence Journal (ADCAIJ is an open access journal that publishes articles which contribute new results associated with distributed computing and artificial intelligence,and their application in different areas. The artificial intelligence is changing our society. Its application in distributed environments, such as the Internet, electronic commerce, mobile communications, wireless devices, distributed computing and so on, is increasing and becoming and element of high added value and economic potential in industry and research. These technologies are changing constantly as a result of the large research and technical effort being undertaken in both universities and businesses. The exchange of ideas between scientists and technicians from both academic and business areas is essential to facilitate the development of systems that meet the demands of today's society. We would like to thank all the contributing authors for their hard and highly valuable work. Their work has helped to contribute to the success of this special issue. Finally, the Editors wish to thank Scientific Committee of Advances in Distributed Computing and Artificial Intelligence Journal for the collaboration of this special issue, that notably contributes to improve the quality of the journal. We hope the reader will share our joy and find this special issue very useful.

  15. Index

    Directory of Open Access Journals (Sweden)

    Antonio Juan Sánchez

    2013-08-01

    Full Text Available The Advances in Distributed Computing and Artificial Intelligence Journal (ADCAIJ is an open access journal that publishes articles which contribute new results associated with distributed computing and artificial intelligence,and their application in different areas.The artificial intelligence is changing our society. Its application in distributed environments, such as the Internet, electronic commerce, mobile communications, wireless devices, distributed computing and so on, is increasing and becoming and element of high added value and economic potential in industry and research. These technologies are changing constantly as a result of the large research and technical effort being undertaken in both universities and businesses. The exchange of ideas between scientists and technicians from both academic and business areas is essential to facilitate the development of systems that meet the demands of today's society.We would like to thank all the contributing authors for their hard and highly valuable work. Their work has helped to contribute to the success of this special issue. Finally, the Editors wish to thank Scientific Committee of Advances in Distributed Computing and Artificial Intelligence Journal for the collaboration of this special issue, that notably contributes to improve the quality of the journal. We hope the reader will share our joy and find this special issue very useful.

  16. Index

    Directory of Open Access Journals (Sweden)

    Antonio Juan SÁNCHEZ

    2012-07-01

    Full Text Available The Advances in Distributed Computing and Artificial Intelligence Journal (ADCAIJ is an open access journal that publishes articles which contribute new results associated with distributed computing and artificial intelligence,and their application in different areas.The artificial intelligence is changing our society. Its application in distributed environments, such as the Internet, electronic commerce, mobile communications, wireless devices, distributed computing and so on, is increasing and becoming and element of high added value and economic potential in industry and research. These technologies are changing constantly as a result of the large research and technical effort being undertaken in both universities and businesses. The exchange of ideas between scientists and technicians from both academic and business areas is essential to facilitate the development of systems that meet the demands of today's society.We would like to thank all the contributing authors for their hard and highly valuable work. Their work has helped to contribute to the success of this special issue. Finally, the Editors wish to thank Scientific Committee of Advances in Distributed Computing and Artificial Intelligence Journal for the collaboration of this special issue, that notably contributes to improve the quality of the journal. We hope the reader will share our joy and find this special issue very useful.

  17. Index

    Directory of Open Access Journals (Sweden)

    Antonio Juan Sánchez

    2013-11-01

    Full Text Available The Advances in Distributed Computing and Artificial Intelligence Journal (ADCAIJ is an open access journal that publishes articles which contribute new results associated with distributed computing and artificial intelligence,and their application in different areas.The artificial intelligence is changing our society. Its application in distributed environments, such as the Internet, electronic commerce, mobile communications, wireless devices, distributed computing and so on, is increasing and becoming and element of high added value and economic potential in industry and research. These technologies are changing constantly as a result of the large research and technical effort being undertaken in both universities and businesses. The exchange of ideas between scientists and technicians from both academic and business areas is essential to facilitate the development of systems that meet the demands of today's society.We would like to thank all the contributing authors for their hard and highly valuable work. Their work has helped to contribute to the success of this special issue. Finally, the Editors wish to thank Scientific Committee of Advances in Distributed Computing and Artificial Intelligence Journal for the collaboration of this special issue, that notably contributes to improve the quality of the journal. We hope the reader will share our joy and find this special issue very useful.

  18. Index

    Directory of Open Access Journals (Sweden)

    Antonio Juan SÁNCHEZ

    2013-07-01

    Full Text Available The Advances in Distributed Computing and Artificial Intelligence Journal (ADCAIJ is an open access journal that publishes articles which contribute new results associated with distributed computing and artificial intelligence,and their application in different areas.The artificial intelligence is changing our society. Its application in distributed environments, such as the Internet, electronic commerce, mobile communications, wireless devices, distributed computing and so on, is increasing and becoming and element of high added value and economic potential in industry and research. These technologies are changing constantly as a result of the large research and technical effort being undertaken in both universities and businesses. The exchange of ideas between scientists and technicians from both academic and business areas is essential to facilitate the development of systems that meet the demands of today's society.We would like to thank all the contributing authors for their hard and highly valuable work. Their work has helped to contribute to the success of this special issue. Finally, the Editors wish to thank Scientific Committee of Advances in Distributed Computing and Artificial Intelligence Journal for the collaboration of this special issue, that notably contributes to improve the quality of the journal. We hope the reader will share our joy and find this special issue very useful.

  19. Evaluation of the data of vegetable covering using fraction images and multitemporal vegetation index, derived of orbital data of moderate resolution of the sensor MODIS

    International Nuclear Information System (INIS)

    The objective was to evaluate the data obtained by sensor MODIS onboard the EOS terra satellite land cover units. The study area is the republic of Colombia in South America. The methodology consisted of analyzing the multitemporal (vegetation, soil and shade-water) fraction images and vegetation indices (NDVI) apply the lineal spectral mixture model to products derived from derived images by sensor MODIS data obtained in years 2001 and 2003. The mosaics of the original and the transformed vegetation (soil and shade-water) bands were generated for the whole study area using SPRING 4. 0 software, developed by INPE then these mosaics were segmented, classified, mapped, and edited to obtain a moderate resolution land cover map. The results derived from MODIS analysis were compared with Landsat ETM+ data acquire for a single test site. The results of the project showed the usefulness of MODIS images for large-scale land cover mapping and monitoring studies

  20. Cultivar discrimination at different site elevations with remotely sensed vegetation indices

    OpenAIRE

    Bruno Basso; Davide Cammarano; Giovanni Cafiero; Stefano Marino; Arturo Alvino

    2011-01-01

    The objectives of this study are (i) to evaluate vegetation indices sensitivity to discriminate between two different cultivars; (ii) to determine the effects of site elevation and developmental stages on cultivar discrimination. The experiment was carried out for the growing season 2007/08 at “Agro di Pesche” (Central Italy, Molise region). Four experimental fields were located at different elevation ranging between 590 m to 922 m above the sea level (asl). For each field...

  1. Soil phosphorus forms as quality indicators of soils under different vegetation covers.

    Science.gov (United States)

    Turrión, María-Belén; López, Olga; Lafuente, Francisco; Mulas, Rafael; Ruipérez, César; Puyo, Alberto

    2007-05-25

    The type of vegetation cover determines the physicochemical and biological properties of the soil over which they are developing. The objective of this study was to determine the effect of different vegetation covers on the forms of soil phosphorus, in order to know which of these forms can be used as a soil quality indicator. The experimental area was located on the acidic plateau at the North of Palencia (North Spain), where an area was selected vegetation covers very close to each other: pine (Pinus sylvestris), oak (Quercus pyrenaica), and three different shrub species (Arctostaphylos uva-ursi, Erica australis and Halimium alyssoides). The Ah horizon was sampled and pH, total organic C (C(org)), total N (N), cationic exchange capacity (CEC), sum of bases (S) and P forms by a sequential fractionation were analysed. Results showed that oak and A. uva-ursi improve the considered soil parameters (pH, C(org)/N ratio, CEC, and S) and provide soils of better quality. Inorganic soil P forms were influenced in greater extent by the vegetation cover than were P organic forms. Labile inorganic P forms could be used as indicators of soil quality. The organic P forms were less sensitive than inorganic ones to the indicated improvements. PMID:17307240

  2. A simple model for yield prediction of rice based on vegetation index derived from satellite and AMeDAS data during ripening period

    International Nuclear Information System (INIS)

    The present study was conducted to show a simple model for rice yield predicting by using a vegetation index (NDVI) derived from satellite and meteorological data. In a field experiment, the relationship between the vegetation index and radiation absorbed by the rice canopy was investigated from transplanting to maturity. Their correlation held. This result revealed that the vegetation index could be used as a measure of absorptance of solar radiation by rice canopy. NDVI multiplied by solar radiation (SR) every day was accumulated (?(SR·NDVI)) from the field experiment. ?(SR·NDVI) was plotted against above ground dry matter. It was obvious that they had a strong relationship. Rice yield largely depends on solar radiation and air temperature during the ripening period. Air temperature affects dry matter production. Relationships between Y SR-1 (Y: rice yield, SR: solar radiation) and mean air temperature were investigated from meteorological data and statistical data on rice yield. There was an optimum air temperature, 21.3°C, for ripening. When it was near 21.3°C in the ripening period, the rice yield was higher. We proposed a simple model for yield prediction of rice based on these results. The model is composed with SR·NDVI and the optimum air temperature. Vegetation index was derived from 3 years, LANDSAT TM data in Toyama, Ishikawa, Fukui and Nagano prefectures at heading. The meteorological data was used from AMeDAS data. The model was described as follows: Y = 0.728 SR·NDVI?2.04(T?21.3)2 + 282 (r2 = 0.65, n = 43) where Y is rice yield (kg 10a-1), SR is solar radiation (MJ m-2) during the ripening period (from 10 days before heading to 30 days after heading), T is mean air temperature (°C) during the ripening period. RMSE was 33.7kg 10a-1. The model revealed good precision. (author)

  3. Environmental quality evaluation. Indexing tools to evaluate environmental quality from biological data, floristic and vegetational data in Ponte Galeria (Rome, Italy)

    International Nuclear Information System (INIS)

    In the present work the study of indexing tools to evaluate environmental quality from biological data has been performed using a certain number of floristic and vegetational indices near Macchia Grande of Ponte Galeria (Rome, Italy). The indices have been applied on the basis of the data coming from a phyto sociological study of the area. Multivariate statistics methodologies have been utilized to obtain a synthetic evaluation of the indices

  4. Analysing and Quantifying Vegetation Responses to Rainfall with High Resolution Spatio-Temporal Time Series Data for Different Ecosystems and Ecotones in Queensland

    Science.gov (United States)

    Schmidt, M.; Udelhoven, T.

    2012-07-01

    Vegetation responses and ecosystem function are spatially variable and influenced by climate variability. The Spatial and Temporal Adaptive Reflectance Fusion Model (STARFM) was used to combine MODIS (Moderate Resolution Imaging Spectrometer) and Landsat TM/ETM+ (Thematic Mapper/ Enhanced Thematic Mapper plus) imagery for an 8 year dataset (2000-2007) at 30m spatial resolution with 8 day intervals. This dataset allows for a functional analysis of ecosystem responses, suitable for heterogeneous landscapes. Derived vegetation index information in form of the NDVI (Normalised Difference Vegetation Index) was used to investigate the relationship between vegetation responses and gridded rainfall data for regional ecosystems. A hierarchical decomposition of the time series has been carried out in which relationships among the time-series were individually assessed for deterministic time-series components (trend component and seasonality) as well as for the stochastic seasonal anomalies. While no common long-term trends in NDVI and rainfall data in the time period considered exist, there is however, a strong concurrence in the seasonally of NDVI and rainfall data. This component accounts for the majority of variability in the time-series. On the level of seasonal anomalies, these relationships are more subtle. The statistical analysis required, among others, the removal of temporal autocorrelation for an unbiased assessment of significance. Significant lagged correlations between rainfall and NDVI were found in complex Queensland savannah vegetation communities. For grasslands and open woodlands, significant relationships with lag times between 8 and 16 days were found. For denser, evergreen vegetation communities greater lag times of up to 2.5 months were found. The derived distributed lag models may be used for short-term NDVI and biomass predictions on the spatial resolution scale of Landsat (30m).

  5. Fully-automated estimation of actual to potential evapotranspiration in the Everglades using Landsat and air temperature data as inputs to the Vegetation Index-Temperature Trapezoid method

    Science.gov (United States)

    Yagci, A. L.; Jones, J. W.

    2014-12-01

    While the greater Everglades contains a vast wetland, evapotranspiration (ET) is a major source of water "loss" from the system. Like other ecosystems, the Everglades is vulnerable to drought. Everglades restoration science and resource management requires information on the spatial and temporal distribution of ET. We developed a fully-automated ET model using the Vegetation Index-Temperature Trapezoid concept. The model was tested and evaluated against in-situ ET observations collected at the Shark River Slough Mangrove Forest eddy-covariance tower in Everglades National Park (Sitename / FLUXNET ID: Florida Everglades Shark River Slough Mangrove Forest / US-Skr). It uses Landsat Surface Reflectance Climate Data from Landsat 5, and Landsat 5 thermal and air temperature data from the Daily Gridded Surface Dataset to output the ratio of actual evapotranspiration (AET) and potential evapotranspiration (PET). When multiplied with a PET estimate, this output can be used to estimate ET at high spatial resolution. Furthermore, it can be used to downscale coarse resolution ET and PET products. Two example outputs covering the agricultural lands north of the major Everglades wetlands extracted from two different dates are shown below along with a National Land Cover Database image from 2011. The irrigated and non-irrigated farms are easily distinguishable from the background (i.e., natural land covers). Open water retained the highest AET/PET ratio. Wetlands had a higher AET/PET ratio than farmlands. The main challenge in this study area is prolonged cloudiness during the growing season.

  6. High-Resolution Precipitation Datasets in South America and West Africa based on Satellite-Derived Rainfall, Enhanced Vegetation Index and Digital Elevation Model

    Directory of Open Access Journals (Sweden)

    Guido Ceccherini

    2015-05-01

    Full Text Available Mean Annual Precipitation is one of the most important variables used in water resource management. However, quantifying Mean Annual Precipitation at high spatial resolution, needed for advanced hydrological analysis, is challenging in developing countries which often present a sparse gauge network and a highly variable climate. In this work, we present a methodology to quantify Mean Annual Precipitation at 1 km spatial resolution using different precipitation products from satellite estimates and gauge observations at coarse spatial resolution (i.e., ranging from 4 km to 25 km. Examples of this methodology are given for South America and West Africa. We develop a downscaling method that exploits the relationship among satellite-derived rainfall, Digital Elevation Model and Enhanced Vegetation Index. Finally, we validate its performance using rain gauge measurements: comparable annual precipitation estimates for both South America and West Africa are retrieved. Validation indicates that high resolution Mean Annual Precipitation downscaled from CHIRP (Climate Hazards Group Infrared Precipitation and GPCC (Global Precipitation Climatology Centre datasets present the best ensemble of performance statistics for both South America and West Africa. Results also highlight the potential of the presented technique to downscale satellite-derived rainfall worldwide.

  7. National Oceanic and Atmospheric Administration Climate Data Record Normalized Difference Vegetation Index

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — National Oceanic and Atmospheric Administration (NOAA) Climate Data Records (CDR) provide historical climate information using data from weather satellites. This...

  8. National Oceanic and Atmospheric Administration Climate Data Record Normalized Difference Vegetation Index

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — National Oceanic and Atmospheric Administration (NOAA) Climate Data Records (CDR) provide historical climate information using data from weather satellites. This...

  9. Recovery of a soil under different vegetation one year after a high intensity wildfire

    Directory of Open Access Journals (Sweden)

    A. Martín

    2013-05-01

    Full Text Available Studies on soil recovery in fragile ecosystems following high intensity wildfires are scarce. The aim of the present investigation is to evaluate the impact of a high intensity wildfire in an ecosystem under different vegetation (shrubland and pinewood located at Vilardevós (Galicia, NW Spain and highly susceptible to suffer soil erosion due to the steep relief and high erositivity of the rainfall. Soil samples were collected from the A horizon (0-5 cm 1 year after the fire and soil quality was evaluated by analysis of several physical, chemical and biochemical properties measured in the fraction chemical properties > physical properties. The data also showed that the fire impact was different depending on the soil vegetation considered (shrubland and pinewood. Moreover, the data confirmed the slow soil recovery in this fragile ecosystem and, therefore, the need of adopting post-fire stabilisation and rehabilitation treatments in order to minimize the post-fire erosion and soil degradation.

  10. The effects of different salt, biostimulant and temperature levels on seed germination of some vegetable species

    Directory of Open Access Journals (Sweden)

    Ertan Yildirim

    2013-12-01

    Full Text Available This research was conducted to determine the effects of two biostimulants (humic acid and biozyme or three different salt (NaCl concentrations at the temperature 10, 15, 20 and 25°C on parsley, leek, celery, tomato, onion, lettuce, basil, radish and garden cress seed germination. Two applications of both biostimulants increased seed germination of parsley, celery and leek at all temperature treatments. Germination rate decreased depending on high salt concentrations. At different salt and temperature levels garden cress was characterised by the highest germination percentage compared to other vegetable species.Interactions between NaCl concentrations and temperatures, as welI as biostimulants and temperatures were significant at p=0.001 in for all vegetable species except onion in NaCl concentrations and temperatures compared to that of the control.

  11. Constructed wetland systems vegetated with different plants applied to the treatment of tannery wastewater

    OpenAIRE

    Calheiros, Cristina S. C.; Rangel, António O.S.S.; Castro, Paula M. L.

    2007-01-01

    Wastewaters from leather processing are very complex and lead to water pollution if discharged untreated, especially due to its high organic loading. In this study the survival of different plant species in subsurface horizontal flow constructed wetlands receiving tannery wastewater was investigated. Five pilot units were vegetated with Canna indica, Typha latifolia, Phragmites australis, Stenotaphrum secundatum and Iris pseudacorus, and a sixth unit was left as an unvegetated control. The...

  12. Woody and Grassy Vegetation Development in Different Landscape Elements of the Curonian Spit

    OpenAIRE

    Algimantas Me?islovas Olšausaks

    2009-01-01

    The species of woody and grassy establish on seashore sands and wastes. These plants are adapted for less favorable existence conditions some of them growing in littoral habitats of excessive moisture and salinity. Other tolerates infertile and dry sand. The purpose of the study have been analyzed the dispersion vegetation in different relief elements of the coastal protective dune look for a relation between woody and grassy plant species to foresee the tendencies of further seashore landsca...

  13. Inter-Comparison of ASTER and MODIS Surface Reflectance and Vegetation Index Products for Synergistic Applications to Natural Resource Monitoring

    OpenAIRE

    Hirokazu Yamamoto; Kayo Fujiwara; Hiroki Yoshioka; Tomoaki Miura

    2008-01-01

    Synergistic applications of multi-resolution satellite data have been of a great interest among user communities for the development of an improved and more effective operational monitoring system of natural resources, including vegetation and soil. In this study, we conducted an inter-comparison of two remote sensing products, namely, visible/near-infrared surface reflectances and spectral vegetation indices (VIs), from the high resolution Advanced Thermal Emission and Reflection Radiometer ...

  14. Scintillation index for two Gaussian laser beams with different wavelengths in weak atmospheric turbulence

    OpenAIRE

    Peleg, Avner; Moloney, Jerome V.

    2006-01-01

    We study propagation of two lowest order Gaussian laser beams with different wavelengths in weak atmospheric turbulence. Using the Rytov approximation and assuming a slow detector we calculate the longitudinal and radial components of the scintillation index for a typical free space laser communication setup. We find the optimal configuration of the two laser beams with respect to the longitudinal scintillation index. We show that the value of the longitudinal scintillation ...

  15. Comparison of different ground techniques to map leaf area index of Norway spruce forest canopy

    OpenAIRE

    L. Homolova; Malenovsky, Z.; Hanus, J.; Tomaskova, I.; Dvoráková, M.; Pokorny, R.

    2007-01-01

    The leaf area index (LAI) of three monocultures of Norway spruce (Picea abies (L.) Karst), different in age and structure, was measured by means of two indirect optical techniques of LAI field mapping: 1/ plant canopy analyser LAI-2000, and 2/ digital hemispherical photographs (DHP). The supportive measurements with the TRAC instrument were conducted to produce mainly the element clumping index. The aim of the study was to compare the performances of LAI-2000 and DHP and to evaluate effect of...

  16. Use of biochemical indices in the mediterranean environment: comparison among soils under different forest vegetation.

    Science.gov (United States)

    Pinzari, F; Trinchera, A; Benedetti, A; Sequi, P

    1999-05-01

    In the present study, soil biomass activity, organic carbon storage, and turnover times were compared in adjacent mediterranean biotopes with different forest vegetation, to analyze the effects of litter diversity and soil management protocols on microbial decomposition rates. Samples of forest soil from four vegetation types were collected at depths of 0-20 and 20-40 cm in the 'Tenuta Presidenziale di Castelporziano' Reserve on the Tyrrhenian coast, near Rome (Italy). The samples were incubated under standard laboratory conditions (-33 kPa water tension, and 30 degrees C), in order to compare the microbial activity independently of temperature and humidity. The CO2-C accumulation curves over a 28-d incubation period showed substantially different kinetics between the samples; in particular, soils with above-ground diversity were characterised by high mineralization activity when compared with those sampled under monospecific vegetation. For all the sites, statistically significant linear correlation was observed between nitrogen concentration and potentially mineralizable carbon (r = 0.97), and microbial biomass carbon (Cmic) to total organic carbon (Corg) ratio and the microbial metabolic quotient q(CO2) (r = -0.96). The q(CO2), indicator of the stability of ecosystems, was enhanced by plant diversity, while the Cmic:Corg ratio was reduced. PMID:10353796

  17. Different effects of economic and structural performance indexes on model construction of structural topology optimization

    Science.gov (United States)

    Yi, G. L.; Sui, Y. K.

    2015-09-01

    The objective and constraint functions related to structural optimization designs are classified into economic and performance indexes in this paper. The influences of their different roles in model construction of structural topology optimization are also discussed. Furthermore, two structural topology optimization models, optimizing a performance index under the limitation of an economic index, represented by the minimum compliance with a volume constraint (MCVC) model, and optimizing an economic index under the limitation of a performance index, represented by the minimum weight with a displacement constraint (MWDC) model, are presented. Based on a comparison of numerical example results, the conclusions can be summarized as follows: (1) under the same external loading and displacement performance conditions, the results of the MWDC model are almost equal to those of the MCVC model; (2) the MWDC model overcomes the difficulties and shortcomings of the MCVC model; this makes the MWDC model more feasible in model construction; (3) constructing a model of minimizing an economic index under the limitations of performance indexes is better at meeting the needs of practical engineering problems and completely satisfies safety and economic requirements in mechanical engineering, which have remained unchanged since the early days of mechanical engineering.

  18. Different effects of economic and structural performance indexes on model construction of structural topology optimization

    Science.gov (United States)

    Yi, G. L.; Sui, Y. K.

    2015-10-01

    The objective and constraint functions related to structural optimization designs are classified into economic and performance indexes in this paper. The influences of their different roles in model construction of structural topology optimization are also discussed. Furthermore, two structural topology optimization models, optimizing a performance index under the limitation of an economic index, represented by the minimum compliance with a volume constraint (MCVC) model, and optimizing an economic index under the limitation of a performance index, represented by the minimum weight with a displacement constraint (MWDC) model, are presented. Based on a comparison of numerical example results, the conclusions can be summarized as follows: (1) under the same external loading and displacement performance conditions, the results of the MWDC model are almost equal to those of the MCVC model; (2) the MWDC model overcomes the difficulties and shortcomings of the MCVC model; this makes the MWDC model more feasible in model construction; (3) constructing a model of minimizing an economic index under the limitations of performance indexes is better at meeting the needs of practical engineering problems and completely satisfies safety and economic requirements in mechanical engineering, which have remained unchanged since the early days of mechanical engineering.

  19. Low perfusion index affects the difference in glucose level between capillary and venous blood

    Directory of Open Access Journals (Sweden)

    Acar N

    2014-11-01

    Full Text Available Nurdan Acar,1 Hamit Ozcelik,1 Arif Alper Cevik,1 Engin Ozakin,1 Goknur Yorulmaz,2 Nur Kebapci,2 Ugur Bilge,3 Muzaffer Bilgin4 1Emergency Department, 2Endocrinology Department, 3Family Medicine Department, 4Biostatistics Department, Medical School, Eskisehir Osmangazi University, Eskisehir, Turkey Aim: In emergency cases, finger stick testing is primarily used to check the blood glucose value of patients since it takes longer to obtain the venous value. In critical patients, under conditions that cause an increase in metabolic state and level of stress, there occurs considerable difference in glucose levels between capillary and venous measurements. This study aimed to investigate the comparability of capillary and venous glucose values, according to the perfusion index level obtained with the Masimo Radical-7® device, in critical patients aged 18 years and over.Method: We conducted this prospective and observational study in the emergency department of the Eskisehir Osmangazi University hospital between November 3, 2008 and February 2, 2009.Results: The blood glucose of 300 critical patients was checked by finger stick in the emergency unit. The participants with normal vital signs had perfusion index between 0 and 5; the results obtained by the two methods were more consistent for perfusion index values of 6 and over. The results were most consistent in aged participants with normal vital sign findings and low perfusion index and in young patients with high perfusion index. In the cases where at least one of the vital signs was abnormal, the glucose values obtained by the two methods were more consistent when the perfusion index was 6 or over. In this group, independently from the perfusion index value, the consistency was higher in younger patients compared with aged patients.Conclusion: In the emergency department, perfusion index value measured by Masimo Radical-7 and capillary blood glucose levels can serve in blood sugar management in critically ill patients. Keyword: glucose, capillary, venous, perfusion index, Masimo Radical-7®

  20. Interpersonal Reactivity Index: Analysis of Invariance and Gender Differences in Spanish Youths

    Science.gov (United States)

    Holgado Tello, Francisco Pablo; Delgado Egido, Begona; Carrasco Ortiz, Miguel A.; Del Barrio Gandara, M. V.

    2013-01-01

    Empathy is understood as a multidimensional construct involving both cognitive and emotional factors for which, traditionally, gender differences have been reported. The Interpersonal Reactivity Index (Davis in Catalog Sel Documents Psychol 10:1-19, 1980) is an instrument made up of four subscales, each measuring a different dimension of the…

  1. Zygosity Differences in Height and Body Mass Index of Twins From Infancy to Old Age

    DEFF Research Database (Denmark)

    Jelenkovic, Aline; Yokoyama, Yoshie; Sund, Reijo; Honda, Chika; Bogl, Leonie H; Aaltonen, Sari; Ji, Fuling; Ning, Feng; Pang, Zengchang; Ordoñana, Juan R; Sánchez-Romera, Juan F; Colodro-Conde, Lucia; Burt, S Alexandra; Klump, Kelly L; Medland, Sarah E; Montgomery, Grant W; Kandler, Christian; McAdams, Tom A; Eley, Thalia C; Gregory, Alice M; Saudino, Kimberly J; Dubois, Lise; Boivin, Michel; Tarnoki, Adam D; Tarnoki, David L; Haworth, Claire M A; Plomin, Robert; Öncel, Sevgi Y; Aliev, Fazil; Stazi, Maria A; Fagnani, Corrado; D'Ippolito, Cristina; Craig, Jeffrey M; Saffery, Richard; Siribaddana, Sisira H; Hotopf, Matthew; Sumathipala, Athula; Rijsdijk, Fruhling; Spector, Timothy; Mangino, Massimo; Lachance, Genevieve; Gatz, Margaret; Butler, David A; Bayasgalan, Gombojav; Narandalai, Danshiitsoodol; Freitas, Duarte L; Maia, José Antonio; Harden, K Paige; Tucker-Drob, Elliot M; Kim, Bia; Chong, Youngsook; Hong, Changhee; Shin, Hyun Jung; Christensen, Kaare; Skytthe, Axel; Kyvik, Kirsten O; Derom, Catherine A; Vlietinck, Robert F; Loos, Ruth J F; Cozen, Wendy; Hwang, Amie E; Mack, Thomas M; He, Mingguang; Ding, Xiaohu; Chang, Billy; Silberg, Judy L; Eaves, Lindon J; Maes, Hermine H; Cutler, Tessa L; Hopper, John L; Aujard, Kelly; Magnusson, Patrik K E; Pedersen, Nancy L; Aslan, Anna K Dahl; Song, Yun-Mi; Yang, Sarah; Lee, Kayoung; Baker, Laura A; Tuvblad, Catherine; Bjerregaard-Andersen, Morten; Beck-Nielsen, Henning; Sodemann, Morten; Heikkilä, Kauko; Tan, Qihua; Zhang, Dongfeng; Swan, Gary E; Krasnow, Ruth; Jang, Kerry L; Knafo-Noam, Ariel; Mankuta, David; Abramson, Lior; Lichtenstein, Paul; Krueger, Robert F; McGue, Matt; Pahlen, Shandell; Tynelius, Per; Duncan, Glen E; Buchwald, Dedra; Corley, Robin P; Huibregtse, Brooke M; Nelson, Tracy L; Whitfield, Keith E; Franz, Carol E; Kremen, William S; Lyons, Michael J; Ooki, Syuichi; Brandt, Ingunn; Nilsen, Thomas Sevenius; Inui, Fujio; Watanabe, Mikio; Bartels, Meike; van Beijsterveldt, Toos C E M; Wardle, Jane; Llewellyn, Clare H; Fisher, Abigail; Rebato, Esther; Martin, Nicholas G; Iwatani, Yoshinori; Hayakawa, Kazuo; Sung, Joohon; Harris, Jennifer R; Willemsen, Gonneke; Busjahn, Andreas; Goldberg, Jack H; Rasmussen, Finn; Hur, Yoon-Mi; Boomsma, Dorret I; Sørensen, Thorkild I A; Kaprio, Jaakko; Silventoinen, Karri

    2015-01-01

    A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins...

  2. Comparative uptake and distribution of trace and toxic elements by different vegetables cultivated on soil amended with sewage sludge

    International Nuclear Information System (INIS)

    Sewage sludge is a source of organic matter and of micro nutrients. However, it may contain heavy metals which, if they accumulate excessively high levels in soil , can have an adverse effect on plants, especially food crops and consumers health. In this study it is observed that uptake of different trace and toxic metal ions varies in different vegetables and some metals shows high accumulation than others. Different type of vegetables (leafy, root and beans) were grown in sludge amended soil on laboratory scale, and investigated to ascertain which type of vegetables are suitable for grown in agricultural land amended with sewage sludge. It is concluded that leafy vegetables accumulate higher concentration of heavy metals and root vegetables are more sensitive to zinc, nickel, lead and chromium. (author)

  3. Radium and uranium levels in vegetables grown using different farming management systems

    International Nuclear Information System (INIS)

    Vegetables grown with phosphate fertilizer (conventional management), with bovine manure fertilization (organic management) and in a mineral nutrient solution (hydroponic) were analyzed and the concentrations of 238U, 226Ra and 228Ra in lettuce, carrots, and beans were compared. Lettuce from hydroponic farming system showed the lowest concentration of radionuclides 0.51 for 226Ra, 0.55 for 228Ra and 0.24 for 238U (Bq kg-1 dry). Vegetables from organically and conventionally grown farming systems showed no differences in the concentration of radium and uranium. Relationships between uranium content in plants and exchangeable Ca and Mg in soil were found, whereas Ra in vegetables was inversely correlated to the cation exchange capacity of soil, leading to the assumption that by supplying carbonate and cations to soil, liming may cause an increase of U and a decrease of radium uptake by plants. The soil to plant transfer varied from 10-4 to 10-2 for 238U and from 10-2 to 10-1 for 228Ra

  4. Radium and uranium levels in vegetables grown using different farming management systems

    Energy Technology Data Exchange (ETDEWEB)

    Lauria, D.C. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN), Av. Salvador Allende s/n, Recreio dos Bandeirantes, Rio de Janeiro, RJ, CEP 22780-160 (Brazil)], E-mail: dejanira@ird.gov.br; Ribeiro, F.C.A. [Centro Regional de Ciencias Nucleares (CRCN/CNEN), Av. Prof. Luiz Freire 200, Cidade Universitaria Recife, PE, CEP 50740-540 (Brazil); Conti, C.C. [Instituto de Radioprotecao e Dosimetria (IRD/CNEN), Av. Salvador Allende s/n, Recreio dos Bandeirantes, Rio de Janeiro, RJ, CEP 22780-160 (Brazil); Loureiro, F.A. [Estacao Experimental de Nova Friburgo, Empresa de Pesquisa Agropecuaria do Estado do Rio de Janeiro, Pesagro (Brazil)

    2009-02-15

    Vegetables grown with phosphate fertilizer (conventional management), with bovine manure fertilization (organic management) and in a mineral nutrient solution (hydroponic) were analyzed and the concentrations of {sup 238}U, {sup 226}Ra and {sup 228}Ra in lettuce, carrots, and beans were compared. Lettuce from hydroponic farming system showed the lowest concentration of radionuclides 0.51 for {sup 226}Ra, 0.55 for {sup 228}Ra and 0.24 for {sup 238}U (Bq kg{sup -1} dry). Vegetables from organically and conventionally grown farming systems showed no differences in the concentration of radium and uranium. Relationships between uranium content in plants and exchangeable Ca and Mg in soil were found, whereas Ra in vegetables was inversely correlated to the cation exchange capacity of soil, leading to the assumption that by supplying carbonate and cations to soil, liming may cause an increase of U and a decrease of radium uptake by plants. The soil to plant transfer varied from 10{sup -4} to 10{sup -2} for {sup 238}U and from 10{sup -2} to 10{sup -1} for {sup 228}Ra.

  5. Comparison of carbon balance in Mediterranean pilot constructed wetlands vegetated with different C4 plant species.

    Science.gov (United States)

    Barbera, Antonio C; Borin, Maurizio; Cirelli, Giuseppe L; Toscano, Attilio; Maucieri, Carmelo

    2015-02-01

    This study investigates carbon dioxide (CO2) and methane (CH4) emissions and carbon (C) budgets in a horizontal subsurface flow pilot-plant constructed wetland (CW) with beds vegetated with Cyperus papyrus L., Chrysopogon zizanioides (L.) Roberty, and Mischantus × giganteus Greef et Deu in the Mediterranean basin (Sicily) during the 1st year of plant growing season. At the end of the vegetative season, M. giganteus showed the higher biomass accumulation (7.4 kg m(-2)) followed by C. zizanioides (5.3 kg m(-2)) and C. papyrus (1.8 kg m(-2)). Significantly higher emissions of CO2 were detected in the summer, while CH4 emissions were maximum during spring. Cumulative CO2 emissions by C. papyrus and C. zizanioides during the monitoring period showed similar trends with final values of about 775 and 1,074 g m(-2), respectively, whereas M. giganteus emitted 3,395 g m(-2). Cumulative CH4 bed emission showed different trends for the three C4 plant species in which total gas release during the study period was for C. papyrus 12.0 g m(-2) and ten times higher for M. giganteus, while C. zizanioides bed showed the greatest CH4 cumulative emission with 240.3 g m(-2). The wastewater organic carbon abatement determined different C flux in the atmosphere. Gas fluxes were influenced both by plant species and monitored months with an average C-emitted-to-C-removed ratio for C. zizanioides, C. papyrus, and M. giganteus of 0.3, 0.5, and 0.9, respectively. The growing season C balances were positive for all vegetated beds with the highest C sequestered in the bed with M. giganteus (4.26 kg m(-2)) followed by C. zizanioides (3.78 kg m(-2)) and C. papyrus (1.89 kg m(-2)). To our knowledge, this is the first paper that presents preliminary results on CO2 and CH4 emissions from CWs vegetated with C4 plant species in Mediterranean basin during vegetative growth. PMID:24743957

  6. Fiber Bragg Grating Modeling, Characterization and Optimization with different index profiles

    Directory of Open Access Journals (Sweden)

    SUNITA UGALE

    2010-09-01

    Full Text Available This paper presents the modeling and characterization of an optical fiber grating for maximum reflectivity, minimum side lobe power wastage. Grating length and refractive index profile are the critical parameters in contributing to performance of fiber Bragg grating. The reflection spectra and side lobes strength were analyzed with different lengths and different refractive index profiles. podization techniques are used to get optimized reflection spectra. The simulations are based on solving coupled mode equations by transfer matrix method that describes the interaction of guided modes.

  7. The environmental vegetation index: A tool potentially useful for arid land management. [Texas and Mexico, plant growth stress due to water deficits

    Science.gov (United States)

    Gray, T. I., Jr.; Mccrary, D. G. (principal investigators)

    1981-01-01

    The NOAA-6 AVHRR data sets acquired over South Texas and Mexico during the spring of 1980 and after Hurricane Allen passed inland are analyzed. These data were processed to produce the Gray-McCrary Index (GMI's) for each pixel location over the selected area, which area contained rangeland and cropland, both irrigated and nonirrigated. The variations in the GMI's appear to reflect well the availability of water for vegetation. The GMI area maps are shown to delineate and to aid in defining the duration of drought; suggesting the possibility that time changes over a selected area could be useful for irrigation management.

  8. Global vegetation-fire pattern under different land use and climate conditions

    Science.gov (United States)

    Thonicke, K.; Poulter, B.; Heyder, U.; Gumpenberger, M.; Cramer, W.

    2008-12-01

    Fire is a process of global significance in the Earth System influencing vegetation dynamics, biogeochemical cycling and biophysical feedbacks. Naturally ignited wildfires have long history in the Earth System. Humans have been using fire to shape the landscape for their purposes for many millenia, sometimes influencing the status of the vegetation remarkably as for example in Mediterranean-type ecosystems. Processes and drivers describing fire danger, ignitions, fire spread and effects are relatively well-known for many fire-prone ecosystems. Modeling these has a long tradition in fire-affected regions to predict fire risk and behavior for fire-fighting purposes. On the other hand, the global vegetation community realized the importance of disturbances to be recognized in their global vegetation models with fire being globally most important and so-far best studied. First attempts to simulate fire globally considered a minimal set of drivers, whereas recent developments attempt to consider each fire process separately. The process-based fire model SPITFIRE (SPread and InTensity of FIRE) simulates these processes embedded in the LPJ DGVM. Uncertainties still arise from missing measurements for some parameters in less-studied fire regimes, or from broad PFT classifications which subsume different fire-ecological adaptations and tolerances. Some earth observation data sets as well as fire emission models help to evaluate seasonality and spatial distribution of simulated fire ignitions, area burnt and fire emissions within SPITFIRE. Deforestation fires are a major source of carbon released to the atmosphere in the tropics; in the Amazon basin it is the second-largest contributor to Brazils GHG emissions. How ongoing deforestation affects fire regimes, forest stability and biogeochemical cycling in the Amazon basin under present climate conditions will be presented. Relative importance of fire vs. climate and land use change is analyzed. Emissions resulting from wildfires, agricultural and woodfuel burning will be quantified and drivers identified. Future projections of climate and land use change are applied to the model to investigate joint effects on future changes in fire, deforestation and vegetation dynamics in the Amazon basin.

  9. Estimating vegetation dryness to optimize fire risk assessment with spot vegetation satellite data in savanna ecosystems

    Science.gov (United States)

    Verbesselt, J.; Somers, B.; Lhermitte, S.; van Aardt, J.; Jonckheere, I.; Coppin, P.

    2005-10-01

    The lack of information on vegetation dryness prior to the use of fire as a management tool often leads to a significant deterioration of the savanna ecosystem. This paper therefore evaluated the capacity of SPOT VEGETATION time-series to monitor the vegetation dryness (i.e., vegetation moisture content per vegetation amount) in order to optimize fire risk assessment in the savanna ecosystem of Kruger National Park in South Africa. The integrated Relative Vegetation Index approach (iRVI) to quantify the amount of herbaceous biomass at the end of the rain season and the Accumulated Relative Normalized Difference vegetation index decrement (ARND) related to vegetation moisture content were selected. The iRVI and ARND related to vegetation amount and moisture content, respectively, were combined in order to monitor vegetation dryness and optimize fire risk assessment in the savanna ecosystems. In situ fire activity data was used to evaluate the significance of the iRVI and ARND to monitor vegetation dryness for fire risk assessment. Results from the binary logistic regression analysis confirmed that the assessment of fire risk was optimized by integration of both the vegetation quantity (iRVI) and vegetation moisture content (ARND) as statistically significant explanatory variables. Consequently, the integrated use of both iRVI and ARND to monitor vegetation dryness provides a more suitable tool for fire management and suppression compared to other traditional satellite-based fire risk assessment methods, only related to vegetation moisture content.

  10. Age and gender differences in disabling foot pain using different definitions of the manchester foot pain and disability index

    OpenAIRE

    Taylor Anne W; Gill Tiffany K; Menz Hylton B; Hill Catherine L

    2011-01-01

    Abstract Background The Manchester Foot Pain and Disability Index (MFPDI) has been used to determine the prevalence of disabling foot pain in several studies, however there is some debate as to which case definition is most appropriate. The objective of this study was to explore age and gender differences in the proportion of people with disabling foot pain using three different case definitions of the MFPDI and for each individual MFPDI item. Methods A random sample of 223 participants aged ...

  11. The dissipation kinetics of malathion in aqueous extracts of different fruits and vegetables.

    Science.gov (United States)

    Rahimi, Shahrzad; Talebi, Khalil; Torabi, Ehssan; Naveh, Vahid Hoseini

    2015-11-01

    The dissipation of malathion in 5% aqueous extracts of some fruits and vegetables including bell pepper, tomato, cucumber, cantaloupe, carrot, and also buffer (control) was investigated at 37 °C for 4 h. The dissipation trend of malathion in the fruit/vegetable samples and buffer followed first-order double-exponential decay (FODED) and simple first-order kinetic (SFOK) models, respectively. The initial dissipation rate of malathion in tomato (DT10=0.05 h), bell pepper (DT10=0.06 h), and carrot (DT10=0.07 h) was faster compared to the other samples. The slowest rate of pesticide decline belonged to cantaloupe (DT50=1.92 h) with a significant difference from the other samples (p?0.01), whereas tomato (DT50=0.43 h) and carrot (DT50=0.53 h) showed the fastest dissipation rate. DT90 values derived from the models revealed no significant difference between the samples except for cantaloupe which had the slowest rate of dissipation (DT90=8.27 h) with a significant difference compared to others (p?0.01). A direct correlation was observed between protein content of the samples and the rate of malathion decline which indicates the role of plant enzymes in degrading malathion residues. PMID:26483084

  12. Satellite monitoring of different vegetation types by differential optical absorption spectroscopy (DOAS in the red spectral range

    Directory of Open Access Journals (Sweden)

    T. Wagner

    2007-01-01

    Full Text Available A new method for the satellite remote sensing of different types of vegetation and ocean colour is presented. In contrast to existing algorithms relying on the strong change of the reflectivity in the red and near infrared spectral region, our method analyses weak narrow-band (few nm reflectance structures (i.e. "fingerprint" structures of vegetation in the red spectral range. It is based on differential optical absorption spectroscopy (DOAS, which is usually applied for the analysis of atmospheric trace gas absorptions. Since the spectra of atmospheric absorption and vegetation reflectance are simultaneously included in the analysis, the effects of atmospheric absorptions are automatically corrected (in contrast to other algorithms. The inclusion of the vegetation spectra also significantly improves the results of the trace gas retrieval. The global maps of the results illustrate the seasonal cycles of different vegetation types. In addition to the vegetation distribution on land, they also show patterns of biological activity in the oceans. Our results indicate that improved sets of vegetation spectra might lead to more accurate and more specific identification of vegetation type in the future.

  13. Phenolic profile evolution of different ready-to-eat baby-leaf vegetables during storage.

    Science.gov (United States)

    Santos, J; Oliveira, M B P P; Ibáñez, E; Herrero, M

    2014-01-31

    Ready-to-eat baby-leaf vegetables market has been growing and offering to consumers convenient, healthy and appealing products, which may contain interesting bioactive compounds. In this work, the composition and the evolution of the phenolic compounds from different baby-leaf vegetables during refrigerated storage was studied. The phenolic compounds were extracted using pressurized liquid extraction (PLE) and the phenolic profile of each sample was analyzed and quantified by using LC-MS and LC-DAD methods, respectively, at the beginning and at the end of a 10-day storage period. The baby-leaf vegetables studied included green lettuce, ruby red lettuce, swiss chard, spinach, pea shoots, watercress, garden cress, mizuna, red mustard, wild rocket and spearmint samples and a total of 203 phenolic compounds were tentatively identified and quantified. The main naturally phenolic compounds identified correspond to glycosylated flavonoids, with exception of green lettuce and spearmint leaves which had a higher content of hydroxycinnamic acids. Quantification of the main compounds showed a 10-fold higher content of total phenolic content of ruby red lettuce (483mgg(-1)) in relation to the other samples, being the lowest values found in the garden cress (12.8mgg(-1)) and wild rocket leaves (8.1mgg(-1)). The total phenolic content only showed a significant change (p<0.05) after storage in the green lettuce (+17.5%), mizuna (+7.8%), red mustard (-23.7%) and spearmint (-13.8%) leaves. Within the different classes of phenolic compounds monitored, the flavonols showed more stable contents than the hydroxycinnamic and hydroxybenzoic acids, although the behavior of each compound varied strongly among samples. PMID:24438834

  14. Emulator based identification of model differences in describing the residence time of vegetation carbon.

    Science.gov (United States)

    Garcia Cantu Ros, Anselmo; Frieler, Katja

    2015-04-01

    The past three decades have witnessed the development of so-called global vegetation models (GVMs), encompassing accurate representations of a wide range of cross-scale biophysical processes, at the core of the carbon dynamics of terrestrial ecosystems. When forced with climate projections derived from Global Circulation Models (GCMs), GVMs enable one to quantify global-scale, multi-decadal impacts in terms of changes in plant type composition and ecosystem-atmosphere fluxes, at different levels of global warming and CO2 atmospheric concentrations. However, impacts estimated along individual emission pathways appear to be specific of the combination GCM--GVM that is used in the quantification of impacts. In order to gain insights into the sources of multi-model uncertainties of impacts in biomes, it is convenient to resort to simplified representations -so called emulators, of dominant processes explaining the response of biomes, in terms of aggregate variables. This work presents novel results, that illustrate the use of emulators in the analysis of inter-model differences. In particular, we build on ISI-MIP model output data to identify sources of uncertainty in the residence time of carbon in natural vegetation, resulting from 4 representative GVMs under the forcing of 4 RCP scenarios. Our results provide a reliable basis for future model improvement, as well as the possibility to efficiently reproduce the response of vegetation along arbitrary trajectories of CO2 and global warming. This is of special interest in the context of integrated impact assessment, where the application of GVMs becomes computationally unaffordable.

  15. Gender differences in Body Mass Index and physical activity of students of the University of Tuzla

    Directory of Open Access Journals (Sweden)

    Atikovic Almir

    2014-10-01

    Full Text Available Background: This study was carried out among undergraduate students at the University of Tuzla (Bosna and Herzegovina with the objective of examining gender differences in the body mass index (BMI and the level of Physical Activity (PA among respondents.

  16. Caseinomacropeptide index in UHT whole milk stored under different conditions of temperature and time

    OpenAIRE

    C.N.B.C. Villanoeva; E.H.P. Andrade; J.C. Baffa Junior; M.R. Souza; M.M.O.P. Cerqueira; Fonseca, L. M.; C.F.A.M. Penna; M.O. Leite

    2014-01-01

    Caseinomacropeptide (CMP) index is a method used to detect adulteration of milk by addition of cheese whey, since CMP is a glycopeptide characteristic produced during cheesemaking, and soluble in the whey phase. The objective of this work was to evaluate the caseinomacropeptide index of UHT milk stored under different temperatures. Six batches of recently processed UHT milk were collected and stored under three temperatures (21ºC, 6ºC, and -12ºC) and analyzed by HPLC in the day of the milk co...

  17. Performance Test of CI Engine with Different Vegetable Oil as a Fuel

    Directory of Open Access Journals (Sweden)

    Mr.Paresh K. Kasundra ¹ *, Prof. Ashish V. Gohil²

    2011-12-01

    Full Text Available Today, the diesel engine is still capable of running on “biodiesel” fuel, which can be produced from a variety of renewable sources, including soyabean oil, canola oil, sunflower oil, cottonseed oil, and animal fats. These sources can be obtained from agricultural feedstocks or by recycling used oil such as cooking grease. Biodiesel is usable in it’s pure form known as “neat biodiesel” or B100. In addition, it is available in various blends with petrodiesel, the most common of which is known as B20(20 percent biodiesel and 80 percent petrodiesel.it is also used in smaller percentage as a lubricating fuel additives.Copious resource of vegetable oil in India and its ease of translation to biodiesel help to save large expenses done on import of petroleum products and monetary growth of country. Biodiesel also generates enormous rural employment and degraded lands can be restored due to plantation of oil plants which help in reducing greenhouse gasses. in this paper we discuss & compare different performance parameters of C.I. engine with different vegetable oil as a fuel

  18. Woody and grassy vegetation development in different landscape elements of the Curonian spit

    Directory of Open Access Journals (Sweden)

    Algimantas Me?islovas Olšausaks

    2009-12-01

    Full Text Available The species of woody and grassy establish on seashore sands and wastes. These plants are adapted for less favorable existence conditions some of them growing in littoral habitats of excessive moisture and salinity. Other tolerates infertile and dry sand. The purpose of the study have been analyzed the dispersion vegetation in different relief elements of the coastal protective dune look for a relation between woody and grassy plant species to foresee the tendencies of further seashore landscape development. It has been established that in locations with intensive flow of visitors a net of trodden paths is formed where the plants cover is disappearing very fast as there are suitable conditions for the springtime and autumn winds to erode the coastal protective dune of the seashore of the Curonian spit. The trodden path in a couple of years turn into 2 – 3 m. vides sand drifting corridors, but the lies of the holiday makers become there 4 – 5 m. wide pit and hollow. After these formations have interconnected they shape deflations of different size. The drifting sand carried by the prevailing western direction winds swamp the beyond coastal dune plains and the outskirts of the forest and sandy meadows. The statistical analysis of projection cover of plant shows that during the last 27 years (from 1982 the conditions for vegetation survival on the Curonian spit seashore sand dunes are gradually deteriorating.

  19. Sexual differences in microhabitat selection of breeding little bustards Tetrax tetrax: Ecological segregation based on vegetation structure

    Science.gov (United States)

    Morales, M. B.; Traba, J.; Carriles, E.; Delgado, M. P.; de la Morena, E. L. García

    2008-11-01

    We examined sexual differences in patterns of vegetation structure selection in the sexually dimorphic little bustard. Differences in vegetation structure between male, female and non-used locations during reproduction were examined and used to build a presence/absence model for each sex. Ten variables were measured in each location, extracting two PCA factors (PC1: a visibility-shelter gradient; PC2: a gradient in food availability) used as response variables in GLM explanatory models. Both factors significantly differed between female, male and control locations. Neither study site nor phenology was significant. Logistic regression was used to model male and female presence/absence. Female presence was positively associated to cover of ground by vegetation litter, as well as overall vegetation cover, and negatively to vegetation density over 30 cm above ground. Male presence was positively related to litter cover and short vegetation and negatively to vegetation density over 30 cm above ground. Models showed good global performance and robustness. Female microhabitat selection and distribution seems to be related to the balance between shelter and visibility for surveillance. Male microhabitat selection would be related mainly to the need of conspicuousness for courtship. Accessibility to food resources seems to be equally important for both sexes. Differences suggest ecological sexual segregation resulting from different ecological constraints. These are the first detailed results on vegetation structure selection in both male and female little bustards, and are useful in designing management measures addressing vegetation structure irrespective of landscape composition. Similar microhabitat approaches can be applied to manage the habitat of many declining farmland birds.

  20. Camera derived vegetation greenness index as proxy for gross primary production in a low Arctic wetland area

    DEFF Research Database (Denmark)

    Westergaard-Nielsen, Andreas; Lund, Magnus; Hansen, Birger Ulf; Tamstorf, Mikkel Peter

    2013-01-01

    The Arctic is experiencing disproportionate warming relative to the global average, and the Arctic ecosystems are as a result undergoing considerable changes. Continued monitoring of ecosystem productivity and phenology across temporal and spatial scales is a central part of assessing the magnitude of these changes. This study investigates the ability to use automatic digital camera images (DCIs) as proxy data for gross primary production (GPP) in a complex low Arctic wetland site. Vegetation gr...

  1. Accuracy of the Temperature-Vegetation Dryness Index using MODIS under water-limited vs. energy-limited evapotranspiration conditions

    DEFF Research Database (Denmark)

    Garcia, Monica; Ferna?ndez, N.; Villagarci?a, L.; Domingo, F.; Puigdefa?bregas, J.; Sandholt, Inge

    2014-01-01

    Water deficit indices based on the spatial relationship between surface temperature (Ts) and NDVI, known as triangle approaches, are widely used for drought monitoring. However, their application has been recently questioned when the main factor limiting evapotranspiration is energy. Even though water is the main control in dryland ecosystems, these can also undergo periods of energy and temperature limitation. In this paper we aimed to: (i) evaluate the TVDI (Temperature-Vegetation Dryness Inde...

  2. Accuracy of the Temperature–Vegetation Dryness Index using MODIS under water-limited vs. energy-limited evapotranspiration conditions

    OpenAIRE

    García, M. (Martín); Fernández, Néstor; Villagarcía, L.; F. Domingo; Puigdefábregas, Juan; Sandhold, I.

    2014-01-01

    Water deficit indices based on the spatial relationship between surface temperature (Ts) and NDVI, known as triangle approaches, are widely used for drought monitoring. However, their application has been recently questioned when the main factor limiting evapotranspiration is energy. Even though water is the main control in dryland ecosystems, these can also undergo periods of energy and temperature limitation. In this paper we aimed to: (i) evaluate the TVDI (Temperature–Vegetation Dryness I...

  3. Scintillation index for two Gaussian laser beams with different wavelengths in weak atmospheric turbulence

    CERN Document Server

    Peleg, A; Peleg, Avner; Moloney, Jerome V.

    2006-01-01

    We study propagation of two lowest order Gaussian laser beams with different wavelengths in weak atmospheric turbulence. Using the Rytov approximation and assuming a slow detector we calculate the longitudinal and radial components of the scintillation index for a typical free space laser communication setup. We find the optimal configuration of the two laser beams with respect to the longitudinal scintillation index. We show that the value of the longitudinal scintillation for the optimal two-beam configuration is smaller by more than 50% compared with the value for a single lowest order Gaussian beam with the same total power. Furthermore, the radial scintillation for the optimal two-beam system is smaller by 35%-40% compared with the radial scintillation in the single beam case. Further insight into the reduction of intensity fluctuations is gained by analyzing the self- and cross-intensity contributions to the scintillation index.

  4. Camera derived vegetation greenness index as proxy for gross primary production in a low Arctic wetland area

    Science.gov (United States)

    Westergaard-Nielsen, Andreas; Lund, Magnus; Hansen, Birger Ulf; Tamstorf, Mikkel Peter

    2013-12-01

    The Arctic is experiencing disproportionate warming relative to the global average, and the Arctic ecosystems are as a result undergoing considerable changes. Continued monitoring of ecosystem productivity and phenology across temporal and spatial scales is a central part of assessing the magnitude of these changes. This study investigates the ability to use automatic digital camera images (DCIs) as proxy data for gross primary production (GPP) in a complex low Arctic wetland site. Vegetation greenness computed from DCIs was found to correlate significantly (R2 = 0.62, p bi-temporal image composite was used to classify the study area into heath, copse, fen, and bedrock. Temporal evolution of vegetation greenness was evaluated and modeled with double sigmoid functions for each plant community. GPP at light saturation modeled from eddy covariance (EC) flux measurements were found to correlate significantly with vegetation greenness for all plant communities in the studied year (i.e., 2010), and the highest correlation was found between modeled fen greenness and GPP (R2 = 0.85, p < 0.001). Finally, greenness computed within modeled EC footprints were used to evaluate the influence of individual plant communities on the flux measurements. The study concludes that digital cameras may be used as a cost-effective proxy for potential GPP in remote Arctic regions.

  5. Caseinomacropeptide index in UHT whole milk stored under different conditions of temperature and time

    Directory of Open Access Journals (Sweden)

    C.N.B.C. Villanoeva

    2014-02-01

    Full Text Available Caseinomacropeptide (CMP index is a method used to detect adulteration of milk by addition of cheese whey, since CMP is a glycopeptide characteristic produced during cheesemaking, and soluble in the whey phase. The objective of this work was to evaluate the caseinomacropeptide index of UHT milk stored under different temperatures. Six batches of recently processed UHT milk were collected and stored under three temperatures (21ºC, 6ºC, and -12ºC and analyzed by HPLC in the day of the milk collection (day 0 and at 30, 60, 90, and 120 days of storage. The experiment was run as a randomized block design with a 3x5 factorial arrangement, and the Student-Newman-Keuls (SNK method was used as the post-hoc test (p = 0.05. There was a progressive increase of the CMP index during the storage period of 120 days, and this indicates the possibility of false positive results if the CMP index is used as an adulteration test for long term stored UHT milk. The validity of the CMP index as an adulteration indicator is only possible soon after packaging, and sample freezing is the only alternative when immediate analysis is not possible. The method was found to be precise, with robust CV of 1.9% even with high CMP levels.

  6. Vegetation succession and soil infiltration characteristics under different aged refuse dumps at the Heidaigou opencast coal mine

    OpenAIRE

    Huang Lei; Zhang Peng; Hu Yigang; Zhao Yang

    2015-01-01

    Vegetation succession and soil infiltration characteristics under five different restoration models of refuse dumps including different-aged revegetated sites (1995, 1998, 2003 and 2005) in the northern, eastern and western open-pit coal mine dump and a reference site with native vegetation, which had never been damaged by coal mining activities on the Heidaigou Open Cut Coal Mine were studied. Changes in the plant species, soil properties and infiltration rates were evaluated at the differen...

  7. STUDY OF SACRAL INDEX: COMPARISON BETWEEN DIFFERENT REGIONAL POPULATIONS OF INDIA AND ABROAD

    Directory of Open Access Journals (Sweden)

    Poornima Janipati

    2014-10-01

    Full Text Available Identification of sex by human skeletal remains is a critical problem and is very important in anthropological and medico legal works. Bones often survive the process of decay and therefore provide the major evidence of human age and sex after death. Over the years different authors had carried various types of measurements on human sacra of different races and regions. The present study carried out 81 sacra of unknown sex contains 45 male and 36 female sacra identified by physical characteristics. They were collected from Telangana and Andhra Pradesh region. India may be divided into four regions like North part, South part, West part, and East part for different study purpose on local population. In the present study mean sacral index in males is 104.08 and females are 115.72. The male mean sacral index value of present study is more than the values of Eastern part, north part, other worker of Southern part of India and western part except in Western part in Western Rajasthan population. The female mean sacral index value of present study is higher than the observation of Eastern part, other workers of Southern part of India, Varanasi and Jammu of north part of India and Saurashtra region of western region of India. Observations of the workers from remaining areas of Western part of India and Agra region of North India is higher than the present study. The studies on Indian population suggest that mean sacral index in females is higher than that of males.

  8. An Empirical Algorithm for Estimating Agricultural and Riparian Evapotranspiration Using MODIS Enhanced Vegetation Index and Ground Measurements of ET. I. Description of Method

    Directory of Open Access Journals (Sweden)

    Edward P. Glenn

    2009-12-01

    Full Text Available We used the Enhanced Vegetation Index (EVI from MODIS to scale evapotranspiration (ETactual over agricultural and riparian areas along the Lower Colorado River in the southwestern US. Ground measurements of ETactual by alfalfa, saltcedar, cottonwood and arrowweed were expressed as fraction of potential (reference crop ETo (EToF then regressed against EVI scaled between bare soil (0 and full vegetation cover (1.0 (EVI*. EVI* values were calculated based on maximum and minimum EVI values from a large set of riparian values in a previous study. A satisfactory relationship was found between crop and riparian plant EToF and EVI*, with an error or uncertainty of about 20% in the mean estimate (mean ETactual = 6.2 mm d?1, RMSE = 1.2 mm d?1. The equation for ETactual was: ETactual = 1.22 × ETo-BC × EVI*, where ETo-BC is the Blaney Criddle formula for ETo. This single algorithm applies to all the vegetation types in the study, and offers an alternative to ETactual estimates that use crop coefficients set by expert opinion, by using an algorithm based on the actual state of the canopy as determined by time-series satellite images.

  9. Zygosity Differences in Height and Body Mass Index of Twins From Infancy to Old Age

    DEFF Research Database (Denmark)

    Jelenkovic, Aline; Yokoyama, Yoshie; Sund, Reijo; Honda, Chika; Bogl, Leonie H; Aaltonen, Sari; Ji, Fuling; Ning, Feng; Pang, Zengchang; Ordoñana, Juan R; Sánchez-Romera, Juan F; Colodro-Conde, Lucia; Burt, S Alexandra; Klump, Kelly L; Medland, Sarah E; Montgomery, Grant W; Kandler, Christian; McAdams, Tom A; Eley, Thalia C; Gregory, Alice M; Saudino, Kimberly J; Dubois, Lise; Boivin, Michel; Tarnoki, Adam D; Tarnoki, David L; Haworth, Claire M A; Plomin, Robert; Öncel, Sevgi Y; Aliev, Fazil; Stazi, Maria A; Fagnani, Corrado; D'Ippolito, Cristina; Craig, Jeffrey M; Saffery, Richard; Siribaddana, Sisira H; Hotopf, Matthew; Sumathipala, Athula; Rijsdijk, Fruhling; Spector, Timothy; Mangino, Massimo; Lachance, Genevieve; Gatz, Margaret; Butler, David A; Bayasgalan, Gombojav; Narandalai, Danshiitsoodol; Freitas, Duarte L; Maia, José Antonio; Harden, K Paige; Tucker-Drob, Elliot M; Kim, Bia; Chong, Youngsook; Hong, Changhee; Shin, Hyun Jung; Christensen, Kaare; Skytthe, Axel; Kyvik, Kirsten O; Derom, Catherine A; Vlietinck, Robert F; Loos, Ruth J F; Cozen, Wendy; Hwang, Amie E; Mack, Thomas M; He, Mingguang; Ding, Xiaohu; Chang, Billy; Silberg, Judy L; Eaves, Lindon J; Maes, Hermine H; Cutler, Tessa L; Hopper, John L; Aujard, Kelly; Magnusson, Patrik K E; Pedersen, Nancy L; Aslan, Anna K Dahl; Song, Yun-Mi; Yang, Sarah; Lee, Kayoung; Baker, Laura A; Tuvblad, Catherine; Bjerregaard-Andersen, Morten; Beck-Nielsen, Henning; Sodemann, Morten; Heikkilä, Kauko; Tan, Qihua; Zhang, Dongfeng; Swan, Gary E; Krasnow, Ruth; Jang, Kerry L; Knafo-Noam, Ariel; Mankuta, David; Abramson, Lior; Lichtenstein, Paul; Krueger, Robert F; McGue, Matt; Pahlen, Shandell; Tynelius, Per; Duncan, Glen E; Buchwald, Dedra; Corley, Robin P; Huibregtse, Brooke M; Nelson, Tracy L; Whitfield, Keith E; Franz, Carol E; Kremen, William S; Lyons, Michael J; Ooki, Syuichi; Brandt, Ingunn; Nilsen, Thomas Sevenius; Inui, Fujio; Watanabe, Mikio; Bartels, Meike; van Beijsterveldt, Toos C E M; Wardle, Jane; Llewellyn, Clare H; Fisher, Abigail; Rebato, Esther; Martin, Nicholas G; Iwatani, Yoshinori; Hayakawa, Kazuo; Sung, Joohon; Harris, Jennifer R; Willemsen, Gonneke; Busjahn, Andreas; Goldberg, Jack H; Rasmussen, Finn; Hur, Yoon-Mi; Boomsma, Dorret I; Sørensen, Thorkild I A; Kaprio, Jaakko; Silventoinen, Karri

    2015-01-01

    A trend toward greater body size in dizygotic (DZ) than in monozygotic (MZ) twins has been suggested by some but not all studies, and this difference may also vary by age. We analyzed zygosity differences in mean values and variances of height and body mass index (BMI) among male and female twins from infancy to old age. Data were derived from an international database of 54 twin cohorts participating in the COllaborative project of Development of Anthropometrical measures in Twins (CODATwins), ...

  10. [Estimation of vegetation water content from Landsat 8 OLI data].

    Science.gov (United States)

    Zheng, Xing-ming; Ding, Yan-ling; Zhao, Kai; Jiang, Tao; Li, Xiao-feng; Zhang, Shi-yi; Li, Yang-yang; Wu, Li-li; Sun, Jian; Ren, Jian-hua; Zhang, Xuan-xuan

    2014-12-01

    The present paper aims to analyze the capabilities and limitations for retrieving vegetation water content from Landsat8 OLI (Operational Land Imager) sensor-new generation of earth observation program. First, the effect of soil background on canopy reflectance and the sensitive band to vegetation water content were analyzed based on simulated dataset from ProSail model. Then, based on vegetation water indices from Landsat8 OLI and field vegetation water content during June 1 2013 to August 14 2013, the best vegetation water index for estimating vegetation water content was found through comparing 12 different indices. The results show that: (1) red, near infrared and two shortwave infrared bands of OLI sensor are sensitive to the change in vegetation water content, and near infrared band is the most sensitive one; (2) At low vegetation coverage, solar radiation reflected by soil background will reach to spectral sensor and influence the relationship between vegetation water index and vegetation water content, and simulation results from ProSail model also show that soil background reflectance has a significant impact on vegetation canopy reflectance in both wet and dry soil conditions, so the optimized soil adjusted vegetation index (OSAVI) was used in this paper to remove the effect of soil background on vegetation water index and improve its relationship with vegetation water content; (3) for the 12 vegetation water indices, the relationship between MSI2 and vegetation water content is the best with the R-square of 0.948 and the average error of vegetation water content is 0.52 kg · m(-2); (4) it is difficult to estimate vegetation water content from vegetation water indices when vegetation water content is larger than 2 kg · m(-2) due to spectral saturation of these indices. PMID:25881444

  11. Sensitivity study of land biosphere CO2 exchange through an atmospheric tracer transport model using satellite-derived vegetation index data

    International Nuclear Information System (INIS)

    We develop a simple, globally uniform model of CO2 exchange between the atmosphere and the terrestrial biosphere by coupling the model with a three-dimensional atmospheric tracer transport model using observed winds, and checking results against observed concentrations of CO2 at various monitoring sites. CO2 fluxes are derived from observed greenness using satellite-derived Global Vegetation Index data, combined with observations of temperature, radiation, and precipitation. We explore a range of CO2 flux formulations together with some modifications of the modelled atmospheric transport. We find that while some formulations can be excluded, it cannot be decided whether or not to make CO2 uptake and release dependent on water stress. It appears that the seasonality of net CO2 fluxes in the tropics, which would be expected to be driven by water availability, is small and is therefore not visible in the seasonal cycle of atmospheric CO2. The latter is dominated largely by northern temperate and boreal vegetation, where seasonality is mostly temperature determined. We find some evidence that there is still considerable CO2 release from soils during northern-hemisphere winter. An exponential air temperature dependence of soil release with a Q10 of 1.5 is found to be most appropriate, with no cutoff at low freezing temperatures. This result is independent of the year from which observed winds were taken. This is remarkable insofar as year-to-year changes in modelled CO2 concentrations caused by changes in the wind data clearly outweigh those caused by year-to-year variability in the climate and vegetation index data. (orig.)

  12. MODIS Vegetation Indices

    Science.gov (United States)

    Huete, Alfredo; Didan, Kamel; van Leeuwen, Willem; Miura, Tomoaki; Glenn, Ed

    Assessments of vegetation condition, cover, change, and processes are major ­components of global change research programs, and are topics of considerable societal relevance. Spectral vegetation indices are among the most widely used satellite data products, which provide key measurements for climate, hydrologic, and biogeochemical studies; phenology, land cover, and land cover change detection; natural resource management and sustainable development. Vegetation indices (VI) are robust and seamless data products computed similarly across all pixels in time and space, regardless of biome type, land cover condition, and soil type, and thus represent true surface measurements. The simplicity of VIs enables their amalgamation across ­sensor systems, which facilitates an ensured continuity of critical datasets for long-term land surface modeling and climate change studies. Currently, a more than two decades long NOAA Advanced Very High Resolution Radiometer (AVHRR)-derived consistent global normalized difference vegetation index (NDVI) land record exists, which has contributed significantly to global biome, ecosystem, and agricultural studies.

  13. Profitability and morphological characters of inter-cropping of different vegetables in tea

    International Nuclear Information System (INIS)

    A field experiment was conducted at National Tea Research Institute, Shinkiari, Mansehra, during 2006-07 to find out the most productive and profitable tea-based intercropping system with different vegetable crops. The vegetables included were brinjal solanum melongena , chilies Capsicum annum, okra Ahle moselous, potato Solanum tuberosum, spinach Spinacia oleracea, garlic Allium sativum, onion Allium cepa, peas Pisum sativum and tomato Lycopersicon esculentum, as intercrop combination in newly planted tea. Intercropping of peas showed up poorest among all other treatments, in net income of Rs. 4,800.0, whereas intercrops significantly affected no. of branches, leaves, fresh and dry weight/plant of tea crop respectively. Considering the net return and total expenditure incurred on raising of intercrops, the highest net profit of Rs. 6,669.0/acre was obtained from potato, followed by garlic at Rs. 6,200.0. All treatments combination is more or less similar in net return, except T/sub 5/. Yield and yield-attributes in all treatments were significantly affected. Whereas branches and fresh weight remained significant among each other except sole tea crop. Agronomic data showed that the cropping days were also varies from 45 to 150 days in all treatments. Therefore it might be more economically viable than sole tea crop, upto complete bush formation. (author)

  14. The Influence of Different Vegetable Oils on Some ?-3 Polyunsaturated Fatty Acids in Broiler Chickens Breast

    Directory of Open Access Journals (Sweden)

    Drago?-Sorin Fota

    2011-05-01

    Full Text Available Taking into consideration that the vegetable oils added to the combined fodder can significantly modify the fatty acids profile in broiler food, through its redirection even the fatty acids profile of carcasses can be modified through enrichment in certain fatty acids and obtaining functional foods. Therefore an experiment was conduced on broilers, made up of three experimental groups, fed with a combined base fodder in which 2% of different fat sources have been incorporated (sunflower oil, soybean oil, linseed oil. After the 42 days growth period, the fatty acids profile, % of fatty acids in 100 g product (EPA, DPA, DHA, ? SFA, ? MUFA, ? PUFA of the chicken from the experimental groups, were determined. Fatty acids were determined using gascromatography. The data obtained after statistic processing and interpretation have highlighted the fact that, concerning the fatty acids profile in the chickens breast, we can observe variations of the determined fatty acids content, what shows us that they can be influenced through dietary factors, but there quantity being determined by the participation % of the energy sources (vegetable oils, but also by the fatty acids content of the participating raw materials.

  15. THE EFFECT OF DIFFERENT TYPES OF STRAW MULCHES ON WEED-CONTROL IN VEGETABLES CULTIVATION

    Directory of Open Access Journals (Sweden)

    Edyta Kosterna

    2014-10-01

    Full Text Available The experiment was carried out in 2010–2012. The effect of different kinds of straw and its dose applied to soil mulching on the amount and fresh mass of weeds and yield level of broccoli and tomato was investigated. The type of straw mulch applied to the soil mulching influenced number and fresh mass of weeds. This effect could be the result of the properties of the mulch (colour, structure, etc. or the allelopathic effect on the germination and growth of individual weed species. The most efficient for limiting infestation was mulch from buckwheat and rye straw. Soil mulching, regardless of its kind, causes a decrease in the number and mass of weeds at the beginning of growing period of vegetables. The application of straw at a dose of 20 t?ha-1 had higher weed-suppressing effect than at a dose of 10 t?ha-1. When assessing the infestation before harvest the influence of straw mulch was lower but still significant. The application in higher dose of rye and buckwheat straw in broccoli, corn and rape in tomato cultivation reduced a number of weeds compared to dose of 10 t?ha-1. The better yielding effect in both vegetable species had soil mulching with straw at a dose of 10 t?ha-1.

  16. Assessing Broadband Vegetation Indices And QuickBird Data In Estimating Leaf Area Index Of Corn And Potato Canopies

    Science.gov (United States)

    Leaf area index (LAI) is a key biophysical variable that can be used to derive agronomic information for field management and yield prediction. In the context of applying broadband and high spatial resolution satellite sensor data to agricultural applications at the field scale, an improved method ...

  17. Association between different measurements of blood pressure variability by ABP monitoring and ankle-brachial index

    Directory of Open Access Journals (Sweden)

    Moreira Leila B

    2010-11-01

    Full Text Available Abstract Background Blood pressure (BP variability has been associated with cardiovascular outcomes, but there is no consensus about the more effective method to measure it by ambulatory blood pressure monitoring (ABPM. We evaluated the association between three different methods to estimate BP variability by ABPM and the ankle brachial index (ABI. Methods and Results In a cross-sectional study of patients with hypertension, BP variability was estimated by the time rate index (the first derivative of SBP over time, standard deviation (SD of 24-hour SBP; and coefficient of variability of 24-hour SBP. ABI was measured with a doppler probe. The sample included 425 patients with a mean age of 57 ± 12 years, being 69.2% women, 26.1% current smokers and 22.1% diabetics. Abnormal ABI (? 0.90 or ? 1.40 was present in 58 patients. The time rate index was 0.516 ± 0.146 mmHg/min in patients with abnormal ABI versus 0.476 ± 0.124 mmHg/min in patients with normal ABI (P = 0.007. In a logistic regression model the time rate index was associated with ABI, regardless of age (OR = 6.9, 95% CI = 1.1- 42.1; P = 0.04. In a multiple linear regression model, adjusting for age, SBP and diabetes, the time rate index was strongly associated with ABI (P Conclusion Time rate index is a sensible method to measure BP variability by ABPM. Its performance for risk stratification of patients with hypertension should be explored in longitudinal studies.

  18. Camera derived vegetation greenness index as proxy for gross primary production in a low Arctic wetland area

    DEFF Research Database (Denmark)

    Westergaard-Nielsen, Andreas; Lund, Magnus; Hansen, Birger Ulf; Tamstorf, Mikkel Peter

    2013-01-01

    of these changes. This study investigates the ability to use automatic digital camera images (DCIs) as proxy data for gross primary production (GPP) in a complex low Arctic wetland site. Vegetation greenness computed from DCIs was found to correlate significantly (R-2 = 0.62, p <0.001) with a...... modeled fen greenness and GPP (R-2 = 0.85, p <0.001). Finally, greenness computed within modeled EC footprints were used to evaluate the influence of individual plant communities on the flux measurements. The study concludes that digital cameras may be used as a cost-effective proxy for potential GPP in...

  19. The variation of components in the radiation balance over different fynbos vegetation types

    International Nuclear Information System (INIS)

    The primary aim of this research is to test whether fynbos vegetation has a high reflection coefficient, and the secondary aim is to consider the vegetation at the sites where the radiation measurements were carried out in order to determine whether similar vegetation structural types have similar radiation regimes. In order to do this six sites were selected in the Cape of Good Hope Nature Reserve. At each site the radiation fluxes were measured for three days during the late summer, giving a total of eighteen days of observation. In addition to the radiation measurements structural data was collected for the vegetation at each site so that comparisons between the radiation fluxes and vegetation could be made. Floristic data was also collected, to typify the vegetation at each site. It has been found that fynbos vegetation, as represented by this study, has an unusually low reflection coefficient which varies from 0,08 -0,13. These values are below those recorded in the literature for other heathland vegetation. On the basis of a numerical classification of the vegetation structural data, it has been found that there is no clear relationship between the vegetation and the various components of the radiation balance

  20. The role of vegetated areas on fish assemblage of the Paraná River floodplain: effects of different hydrological conditions

    Directory of Open Access Journals (Sweden)

    Juan José Neiff

    2009-03-01

    Full Text Available In this paper, we analyze the changes in composition and abundance of fish assemblages in seven vegetated floodplain wetlands with different connectivity across different hydrologic conditions: after a prolonged connection of the floodplain with the main channel, during receding water, and after a prolonged isolation. We also investigated the size and abundance of large-sized migratory species found in these wetlands and the food resources exploited by the dominant fish. Fishes were captured by diurnal seining (8.0 m x 1.50 m, 5 mm mesh along macrophyte banks. Despite the high total number of species registered (100, sample species richness varied between 7 and 31, depending on the sampling site and the sampling date. Cluster analysis indicated low similarity between sites during both the isolation and the prolonged connection. Species turnover decreased from high water (? = 40.33 to low water (? = 33.83, with the minimum value of beta diversity index obtained during the isolation of the floodplain wetlands (? = 26.83. Our results indicated that different dominant populations of fish occur in different hydrological conditions, even though high water and isolation phases occur in the same season of different years. The ordination (NMDS indicated the importance of hydrologic conditions in structuring fish assemblages in the studied floodplain. Small-sized characids, typically associated with macrophytes, dominated the fish assemblages, whereas the younger stages of large sized migratory species were found in low abundance. The maximum standard length of the fish captured was 28 cm and for large migratory fish, standard length varied between 1.6 and 25.0 cm. The dominant fish used several food resources, but littoral macrophytes-associated organisms had a high frequency of occurrence in the three hydrologic conditions. The high species richness of fish in the small, vegetated lakes was related to the high spatial heterogeneity during different hydrological conditions. Disturbances in the hydrological pulses could reduce the biodiversity by modifying the connectivity of the floodplain with the river channel. Conservation of these vegetated wetlands requires maintenance of actual width range of connectivity that provide diverse habitat along the time.Neste artigo analisamos as mudanças na composição e abundância das assembléias de peixes de sete áreas úmidas de planície de inundação com vegetação e com diferentes conectividades e em diferentes condições hidrológicas: depois de uma conexão prolongada da planície de inundação com o canal principal, durante o recuo das águas e após um isolamento prolongado. Nós também investigamos o tamanho e abundância das espécies migratórias de grande tamanho encontradas nestas áreas úmidas e os recursos alimentares explorados pelas espécies dominantes. Os peixes foram capturados com rede durante o dia (8.0 m x 1.50 m, malha de 5 mm nos bancos de macrófitas. Apesar do alto número de espécies registradas (100, a riqueza de espécies nas amostras variou entre 7 e 31, de acordo com o local e data de coleta. A análise de cluster indicou uma baixa similaridade entre os locais tanto durante o período de isolamento como no de conexão prolongada. A substituição de espécies decresceu do período de cheia (? = 40.33 a vazante (? = 33.83, com o valor mínimo de índice de diversidade beta obtido durante o isolamento das áreas úmidas da planície de inundação (? = 26.83. Os resultados indicaram que diferentes populações dominantes de peixes ocorrem em condições hidrológicas diferentes, mesmo quando fases de cheia e de isolamento ocorreram na mesma estação em anos diferentes. A ordenação (NMDS indicou a importância das condições hidrológicas na estruturação das assembléias de peixes na planície de inundação estudada. Caracídeos de pequeno tamanho, tipicamente associados à macrófitas, dominaram a assembléia de peixes, enquanto que indivíduos jovens de espécies de maior porte e migratórias f

  1. High resolution mapping of Normalized Difference Vegetation Indices (NDVI) of biological soil crusts

    Science.gov (United States)

    Fischer, T.; Veste, M.; Eisele, A.; Bens, O.; Spyra, W.; Hüttl, R. F.

    2012-04-01

    Normalized Difference Vegetation Indices (NDVI) are typically determined using satellite or airborne remote sensing, or field portable spectrometers, which give an averaged signal on centimetre to meter scale plots. Biological soil crust (BSC) patches may have smaller sizes, and ecophysiological, hydrological as well as pedological processes may be heterogeneously distributed within this level of resolution. A ground-based NDVI imaging procedure using low-cost equipment (Olympus Camedia 5000z digital camera equipped with a Hoya R72 infrared filter) was developed in this study to fill this gap at the level of field research, where carrying costly and bulky equipment to remote locations is often the limiting factor for data collection. A commercially available colour rendition chart (GretagMacbeth ColorChecker®) with known red (600-700 nm) and NIR (800-900 nm) reflectances was placed into each scene and used for calibration purposes on a per-image basis. Generation of NDVI images involved (i) determination of red and NIR reflectances from the pixel values of the red and NIR channels, respectively, and (ii) calculation and imaging of the NDVI, where NDVI values of -1 to +1 were mapped to grey values of 0 to 255. The correlation between NDVI values retrieved from these images and NDVI values determined using conventional field spectrometry (ASD FieldSpec 3 portable spectroradiometer) was close (r2 =0.91), the 95% confidence interval amounted to 0.10 NDVI units. The pixel resolution was 0.8 mm in the field and 0.2 mm in the laboratory, but can still be improved significantly with closer distance to the crust or with higher camera resolution. Geostatistical analysis revealed that both spatial variability as well as size of individual objects characterized by the NDVI increased with crust development. The latter never exceeded 4 mm in the investigated crusts, which points to the necessity of high resolution imaging for linking remote sensing with ecophysiology. Perspectively, the new method could be used for field monitoring of both biological soil crusts and vascular vegetation. Literature: Fischer, T., Veste, M., Eisele, A., Bens, O., Spyra, W., Hüttl, R.F. (2012) Small Scale Spatial Heterogeneity of Normalized Difference Vegetation Indices (NDVI) and Hot Spots of Photosynthesis in Biological Soil Crusts. Flora (accepted) DOI: 10.1016/j.flora.2012.01.001 Spröte, R., Fischer, T., Veste, M., Raab, T., Wiehe, W., Lange, P., Bens, O., Hüttl, R.F. (2010): Biological topsoil crusts at early successional stages on Quaternary substrates dumped by mining in Brandenburg, NE Germany. Géomorphologie: relief, processus, environnement 4/2010: 359-370

  2. Evaluation of MODIS vegetation indices for detecting deforestation in Amazonia

    OpenAIRE

    Yosio Edemir Shimabukuro; Antonio Roberto Formaggio; Antonio Henrique Correia; Valdete Duarte

    2007-01-01

    Vegetation indices (NDVI and EVI) obtained from MODIS products (250 m and 500m, surface reflectance) were evaluated in relation to the possibility of detecting and monitoring deforestation areas in Amazonia. A new vegetation index, the DNRG (Normalized Difference between Red and Green spectral bands), was proposed with the same objective. The radiometric quality of the multi-date MODIS products was evaluated to verify the possibility of using vegetation index to generate deforestation maps. T...

  3. Towards a tool to design vegetated strips for mitigation of pesticides transfers in surface runoff. Assessment of different scenarios

    OpenAIRE

    Carluer, N.; Giannone, G; Gouy, V.; Gril, J.J.

    2009-01-01

    Vegetated strips can be useful in order to limit pesticides fluxes transferred from agricultural fields towards surface waters. However, these structures must be relevantly situated and well proportioned to be efficient enough. In this study, we assess the efficiencyof vegetative strips to limit surface runoff in contrasted situations, representative of different parts of France. The modelling tool is a version of HYDRUS 2D coupled with a kinematic wave equation, which allows to represent joi...

  4. Fourier Transform Infrared Spectroscopy (FTIR) and Multivariate Analysis for Identification of Different Vegetable Oils Used in Biodiesel Production

    OpenAIRE

    Rosana de Cássia de Souza Schneider; Adilson Ben da Costa; Luciano Marder; Marco Flôres Ferrão; Daniela Mueller

    2013-01-01

    The main objective of this study was to use infrared spectroscopy to identify vegetable oils used as raw material for biodiesel production and apply multivariate analysis to the data. Six different vegetable oil sources—canola, cotton, corn, palm, sunflower and soybeans—were used to produce biodiesel batches. The spectra were acquired by Fourier transform infrared spectroscopy using a universal attenuated total reflectance sensor (FTIR-UATR). For the multivariate analysis principal component ...

  5. Vegetation structure and composition across different land use in a semi-arid savanna of southern Zimbabwe

    OpenAIRE

    Zisadza-Gandiwa, P.; Mango, L.; Gandiwa, E.; Goza, D.; Parakasingwa, C.; Chinoitezvi, E.; Shimbani, J.; Muvengwi, J.

    2013-01-01

    We compared the structure and composition of vegetation communities across different land uses in the northern Gonarezhou National Park and adjacent areas, southeast Zimbabwe. Vegetation data were collected from 60 sample plots using a stratified random sampling technique from April to May 2012. Stratification was by land use, and sample plots in all three strata occurred on predominantly siallitic soils. Our results show that the communal area had higher woody plant species diversity (H' = 2...

  6. PSYCHOLOGICAL AND VEGETATIVE CHARACTERISTICS OF STUDENTS--YAKUTS WITH DIFFERENT EDUCATIONAL SUCCESS.

    Science.gov (United States)

    Stepanova, G K; Ustinova, M V

    2015-01-01

    Consideration of ethnic features of adaptation of students to educational activity in high school is needed as to optimize the learning process and to preserve the functional reserves of the organism. We investigated the characteristics of the psychological status and correlated them with the heart rhythm variability in students Yakuts with varying different effectiveness of educational success. Regression analysis of the relationship of personality psychological characteristics of students with indicators of the spectral power of heart rate showed that more adaptive resource autonomic regulation of the heart have people with an average level of introversion and of personal anxiety indicators corresponding to the transition from moderate to high degree and also in individuals with an average levels of neuroticism. Revealed higher effectiveness of examinations students introverted compared to extroverts and students with high personal anxiety relatively to persons with moderate personal anxiety. High efficiency of intellectual activity of students is achieved through high tension mechanisms vegetative regulation of the heart. PMID:26887113

  7. Simulation Models of Leaf Area Index and Yield for Cotton Grown with Different Soil Conditioners

    Science.gov (United States)

    Su, Lijun; Wang, Quanjiu; Wang, Chunxia; Shan, Yuyang

    2015-01-01

    Simulation models of leaf area index (LAI) and yield for cotton can provide a theoretical foundation for predicting future variations in yield. This paper analyses the increase in LAI and the relationships between LAI, dry matter, and yield for cotton under three soil conditioners near Korla, Xinjiang, China. Dynamic changes in cotton LAI were evaluated using modified logistic, Gaussian, modified Gaussian, log normal, and cubic polynomial models. Universal models for simulating the relative leaf area index (RLAI) were established in which the application rate of soil conditioner was used to estimate the maximum LAI (LAIm). In addition, the relationships between LAIm and dry matter mass, yield, and the harvest index were investigated, and a simulation model for yield is proposed. A feasibility analysis of the models indicated that the cubic polynomial and Gaussian models were less accurate than the other three models for simulating increases in RLAI. Despite significant differences in LAIs under the type and amount of soil conditioner applied, LAIm could be described by aboveground dry matter using Michaelis-Menten kinetics. Moreover, the simulation model for cotton yield based on LAIm and the harvest index presented in this work provided important theoretical insights for improving water use efficiency in cotton cultivation and for identifying optimal application rates of soil conditioners. PMID:26536468

  8. Socio-economic factors, lifestyle and gender differences in body mass index in rural India

    OpenAIRE

    Barker, Mary; Chorghade, Ginny; Crozier, Sarah; Leary, Sam; Fall, Caroline

    2006-01-01

    A survey of the nutritional status of women in six villages in the Pune district of Maharashtra, India found young women to have significantly lower body mass index (BMI) than their male peers. The purpose of this study was to identify social and economic factors associated with this difference in thinness, and to explore the behaviour in men and women that might underlie these associations. We compared men and women in 90 families in this part of Maharashtra, recording social and economic de...

  9. Cholesterol levels and nutritional composition of commercial layers eggs fed diets with different vegetable oils

    Scientific Electronic Library Online (English)

    ABG, Faitarone; EA, Garcia; R de O, Roça; H de A, Ricardo; E N de, Andrade; K, Pelícia; F, Vercese.

    2013-03-01

    Full Text Available This experiment aimed at evaluating the effects of the supplementation of different vegetable oils at different levels to the diet of commercial layers on egg cholesterol levels and nutritional composition (proteins, total solids, lipids, and ashes) for 112 days. Birds were distributed according to [...] a completely randomized experimental design with 10 treatments (T1 - control; T2 - inclusion of 2.5% rapeseed oil; T3 - inclusion of 2.5% canola oil; T4 - inclusion of 2.5% soybean oil; T5 - inclusion of 5% rapeseed oil; T6 - inclusion of 5% canola oil; T7 - inclusion of 5% soybean oil; T8 - inclusion of 2.5% rapeseed oil + 2.5% soybean oil; T9 - inclusion 2.5% canola oil + 2.5% soybean oil; T10 - inclusion of 2.5% rapeseed oil + 2.5% canola oil) of six replicates of eight birds each, totaling 480 birds. Yolk cholesterol levels and nutritional composition were determined on days 20, 60 and 112 days of the experimental period. Data obtained during the experimental period were submitted to analysis of variance. Egg yolks produced by layer fed oils presented lower cholesterol levels after 20 days of inclusion in the experimental diets. On days 60 and 112, cholesterol levels were higher. It was concluded that supplementing layer diets with vegetable oils rich in polyunsaturated fatty acids does not change the nutritional composition of egg yolks. The supply of diets containing oils rich in polyunsaturated fatty acids does not reduce yolk cholesterol content.

  10. Recovery of different waste vegetable oils for biodiesel production: a pilot experience in Bahia State, Brazil.

    Science.gov (United States)

    Torres, Ednildo Andrade; Cerqueira, Gilberto S; Tiago, M Ferrer; Quintella, Cristina M; Raboni, Massimo; Torretta, Vincenzo; Urbini, Giordano

    2013-12-01

    In Brazil, and mainly in the State of Bahia, crude vegetable oils are widely used in the preparation of food. Street stalls, restaurants and canteens make a great use of palm oil and soybean oil. There is also some use of castor oil, which is widely cultivated in the Sertão Region (within the State of Bahia), and widely applied in industry. This massive use in food preparation leads to a huge amount of waste oil of different types, which needs either to be properly disposed of, or recovered. At the Laboratorio Energia e Gas-LEN (Energy & Gas lab.) of the Universidade Federal da Bahia, a cycle of experiments were carried out to evaluate the recovery of waste oils for biodiesel production. The experiences were carried out on a laboratory scale and, in a semi-industrial pilot plant using waste oils of different qualities. In the transesterification process, applied waste vegetable oils were reacted with methanol with the support of a basic catalyst, such as NaOH or KOH. The conversion rate settled at between 81% and 85% (in weight). The most suitable molar ratio of waste oils to alcohol was 1:6, and the amount of catalyst required was 0.5% (of the weight of the incoming oil), in the case of NaOH, and 1%, in case of KOH. The quality of the biodiesel produced was tested to determine the final product quality. The parameters analyzed were the acid value, kinematic viscosity, monoglycerides, diglycerides, triglycerides, free glycerine, total glycerine, clearness; the conversion yield of the process was also evaluated. PMID:23993759

  11. Cholesterol levels and nutritional composition of commercial layers eggs fed diets with different vegetable oils

    Directory of Open Access Journals (Sweden)

    ABG Faitarone

    2013-03-01

    Full Text Available This experiment aimed at evaluating the effects of the supplementation of different vegetable oils at different levels to the diet of commercial layers on egg cholesterol levels and nutritional composition (proteins, total solids, lipids, and ashes for 112 days. Birds were distributed according to a completely randomized experimental design with 10 treatments (T1 - control; T2 - inclusion of 2.5% rapeseed oil; T3 - inclusion of 2.5% canola oil; T4 - inclusion of 2.5% soybean oil; T5 - inclusion of 5% rapeseed oil; T6 - inclusion of 5% canola oil; T7 - inclusion of 5% soybean oil; T8 - inclusion of 2.5% rapeseed oil + 2.5% soybean oil; T9 - inclusion 2.5% canola oil + 2.5% soybean oil; T10 - inclusion of 2.5% rapeseed oil + 2.5% canola oil of six replicates of eight birds each, totaling 480 birds. Yolk cholesterol levels and nutritional composition were determined on days 20, 60 and 112 days of the experimental period. Data obtained during the experimental period were submitted to analysis of variance. Egg yolks produced by layer fed oils presented lower cholesterol levels after 20 days of inclusion in the experimental diets. On days 60 and 112, cholesterol levels were higher. It was concluded that supplementing layer diets with vegetable oils rich in polyunsaturated fatty acids does not change the nutritional composition of egg yolks. The supply of diets containing oils rich in polyunsaturated fatty acids does not reduce yolk cholesterol content.

  12. Analyzing the vegetation response under different treatments after wildfires in NE Spain

    Science.gov (United States)

    León, Javier; Cerdà, Artemi; Badía, David; Echeverría, Maite; Martí, Clara

    2014-05-01

    Fire is a natural factor of landscape evolution in Mediterranean ecosystems. The socio-economic changes that occurred in the last decades have contributed to an increase in forest fires (Shakesby, 2011). There was found a change in the fire regimes in terms of frequency, size, seasonality, recurrence as well as fire intensity and severity (Keeley, 2009), which resulted in severe effects on soils, water and vegetation (Guénon et al., 2013). Fire affects soil properties directly by the heat impact (Aznar et al., 2013), and the ash cover (Cerdà and Doerr, 2008) and the reduction of the plant cover (Neary et al., 1999). The lack of vegetation and the heating promotes changes in the soil organic matter content (González-Pérez et al., 2004), on the structural stability (Mataix-Solera et al., 2011), on the hydrophobic response (Bodí et al., 2012), and on the infiltration capacity (Cerdà, 1998a). This is why the vegetation cover and the litter are key factors on soil erosion after forest fires (Prats et al., 2013). Besides, the ash plays an important paper in the soil protection after the forest fire and after the first storms and winds (León et al., 2013; Pereira et al., 2013). The objective of this experiment is to asses the vegetation response after a forest fire and the impact of vegetation recovery on soil erosion. The experiment consisted in a sampling of a linear transect of 10 m with samples each 2 m, under different slope position and aspect. To measure the soil erosion rates we used rainfall simulation experiments (León et al., 2013). The experiments were carried in Castejón (UTM 30T, X671106, Y4644584) in a forest burned in 2008, in the Zuera Mountains, both located in the north of Zaragoza province (NE Spain). The soils on limestone parent material are Rendzic Phaeozem (IUSS, 2007) and the texture of Ah horizons of soils developed on limestone is sandy-loam (Badía et al., 2013). The result shows fast and successful vegetation regeneration in the north-facing slopes, and a delayed recovery on the south-facing slopes. The soil erosion control treatments shown a very efficient response when Chipped branches covered the soil. References Aznar, J.M., González-Pérez, J.A., Badía, D., Martí, C. 2013. At what depth are the properties of a Gypseous forest topsoil affected by burning?. Land Degradation and Development, DOI: 10.1002/ldr.2258 Badía, D., Martí, C., Aznar, J.M., León, J. 2013. Influence of slope and parent rock on soil genesis and classification in semiarid mountainous environments. Geoderma 193-194: 13-21, doi: http://dx.doi.org/10.1016/j.geoderma.2012.10.020. Bodí, M.B., Doerr, S.H., Cerdà, A., and Mataix-Solera, J. 2012. Hydrological effects of a layer of vegetation ash on underlying wettable and water repellent soil. Geoderma, 191: 14-23. Cerdà, A. 1998a. Postfire dynamics of erosional processes under mediterranean climatic conditions. Zeitschrift für Geomorphologie, 42 (3) 373-398. Cerdà, A. 1998b. The influence of aspect and vegetation on seasonal changes in erosion under rainfall simulation on a clay soil in Spain. Canadian Journal of Soil Science 78, 321-330. Cerdà, A., Doerr, S.H., 2008. The effect of ash and needle cover on surface runoff and ersion in the inmediate post-fire period. Catena 74, 256-263. González-Pérez, J.A., González-Vila, F.J., Almendros, G., Knicker, H. 2004. The effect of fire on soil organic matter - a review. Enviroment International, 30: 855-870. Guénon, R., Vennetier, M., Dupuy, N., Roussos, S., Pailler, A., Gros, R. 2013. Trends in recovery of Mediterranean soil chemical properties and microbial activities after infrequent and frequent wildfires. Land Degradation & Development, 24: 115-128, DOI: 10.1002/ldr.1109. Keeley, J.E. 2009. Fire intensity, fire severity and burn severity: a brief review and suggests usage. International Journal of Wildland Fire, 18: 116-126. León, J., Bodí, M.B., Cerdà, A., Badía, D., 2013. The contrasted response of ash to wetting: The effects of ash type, thickness and rainfall events. Geoderma 209-210, 143-152. Mataix-Solera, J., Cerdà, A., Arcenegui, V., Jordán, A., Zavala, L.M., 2011. Fire effects on soil aggregation: a review. Earth-Science Reviews, 109: 44-60. Neary, D.G., Klopatek, C.C., DeBano, L.F., Ffolliot, P. 1999. Fire effects on belowground sustainability: a review and synthesis. Forest Ccol. Manag., 122: 51-71. Pereira, P., Cerdà, A., Úbeda, X., Mataix-Solera, J., Martin, D., Jordán, A., Burguet, M. 2013. Spatial models for monitoring the spatio-temporal evolution of ashes after fire - a case study of a burnt grassland in Lithuania. Solid Earth, 4: 153-165. Prats, S.A., Malvar, M.C., Simões-Vieira, D.C., MacDonald, L., and Keizer, J.J. 2013. Effectiveness of hydromulching to reduce runoff and erosion in a recently burnt pine plantation in central Portugal. Land Degradation & Development, DOI: 10.1002/ldr.2236. Shakesby, R.A. 2011. Post-wildfire soil erosion in the Mediterranean: Review and future research directions. Earth Science Reviews, 105, 71-100.

  13. Soil contamination by phthalate esters in Chinese intensive vegetable production systems with different modes of use of plastic film

    International Nuclear Information System (INIS)

    The concentrations of six priority phthalic acid esters (PAEs) in intensively managed suburban vegetable soils in Nanjing, east China, were analyzed using gas chromatography–mass spectrometry (GC–MS). The total PAE concentrations in the soils ranged widely from 0.15 to 9.68 mg kg?1 with a median value of 1.70 mg kg?1, and di-n-butyl phthalate (DnBP), bis-(2-ethylhexyl) phthalate (DEHP) and di-n-octyl phthalate (DnOP) were the most abundant phthalate esters. Soil PAE concentrations depended on the mode of use of plastic film in which PAEs were incorporated as plasticizing agents and both the plastic film and poultry manure appeared to be important sources of soil PAEs. Vegetables in rotation with flooded rice led to lower concentrations of PAEs in soil. The results indicate that agricultural plastic film can be an important source of soil PAE contamination and further research is required to fully elucidate the mechanisms of PAE contamination of intensive agricultural soils with different use modes of use of plastic film. -- Highlights: •Phthalate esters in soils from suburban intensive vegetable production systems were investigated. •Phthalate levels and risks of the vegetable soils with different plastic film use modes were examined. •Sources of phthalate esters in vegetable production soils were analyzed. -- PAE contamination of intensively managed vegetable soils varied widely depending on the mode of use of plastic film in different production systems

  14. Measurement of air refractive index fluctuation based on interferometry with two different reference cavity lengths.

    Science.gov (United States)

    Chen, Qianghua; Luo, Huifu; Wang, Sumei; Wang, Feng; Chen, Xinhua

    2012-09-01

    A measurement method based on interferometry with two different reference cavity lengths is presented and applied in air refractive index measurement in which the two cavity lengths and a laser wavelength are combined to generate two wavelength equivalents of cavity. Corresponding calculation equations are derived, and the optical path configuration is designed, which is inspired by the traditional synthetic wavelength method. Theoretical analyses indicate that the measurement uncertainty of the determined index of refraction is about 2.3×10(-8), which is mainly affected by the length precision of the long vacuum cavity and the ellipticity of polarization components of the dual-frequency laser, and the range of nonambiguity is 3.0×10(-5), which is decided by the length difference of the two cavities. Experiment results show that the accuracy of air refractive index measurement is better than 5.0×10(-8) when the laboratory conditions changes slowly. The merit of the presented method is that the classical refractometry can be also used without evacuation of the gas cavity during the experiment. Furthermore, the application of the traditional synthetic wavelength method may be extended by using the wavelength equivalents of cavity, any value of which can be easily acquired by changing cavity length rather than using actual wavelengths whose number is limited. PMID:22945157

  15. Spatial Solitons in 2D Graded-Index Waveguides with Different Distributed Transverse Diffractions

    International Nuclear Information System (INIS)

    We discuss the nonlinear Schrödinger equation with variable coefficients in 2D graded-index waveguides with different distributed transverse diffractions and obtain exact bright and dark soliton solutions. Based on these solutions, we mainly investigate the dynamical behaviors of solitons in three different diffraction decreasing waveguides with the hyperbolic, Gaussian and Logarithmic profiles. Results indicate that for the same parameters, the amplitude of bright solitons in the Logarithmic profile and the amplitude of dark solitons in the Gaussian profile are biggest respectively, and the amplitude in the hyperbolic profile is smallest, while the width of solitons has the opposite case. (general)

  16. Lens-free inline holographic microscopy with numerical correction of layers with different refractive index.

    Science.gov (United States)

    Kanka, Mario; Riesenberg, Rainer

    2015-03-01

    Digital inline holographic microscopy is applied for lens-free imaging with high lateral resolution. Microfluidic chambers for the imaging of cells in water-like or native solutions, e.g., thick layers of glass and other materials with different refractive index, cause aberrations that limit the spatial resolution and change the magnification scale. In this Letter, a fast reconstruction technique considering parallel layer systems of different refractive indices is presented. In the experiments, properly scaled images of microbeads and red human blood cells with an optical resolution corresponding to a numerical aperture of about 0.62 were reconstructed. PMID:25723424

  17. Animal performance and meat characteristics in steers reared in intensive conditions fed with different vegetable oils.

    Science.gov (United States)

    Castro, T; Cabezas, A; De la Fuente, J; Isabel, B; Manso, T; Jimeno, V

    2016-03-01

    Enhancing the quality of beef meat is an important goal in terms of improving both the nutritional value for the consumer and the commercial value for producers. The aim of this work was to study the effects of different vegetable oil supplements on growth performance, carcass quality and meat quality in beef steers reared under intensive conditions. A total of 240 Blonde D' Aquitaine steers (average BW=293.7±38.88 kg) were grouped into 24 batches (10 steers/batch) and were randomly assigned to one of the three dietary treatments (eight batches per treatment), each supplemented with either 4% hydrogenated palm oil (PALM) or fatty acids (FAs) from olive oil (OLI) or soybean oil (SOY). No differences in growth performance or carcass quality were observed. For the meat quality analysis, a steer was randomly selected from each batch and the 6th rib on the left half of the carcass was dissected. PALM meat had the highest percentage of 16:0 (PPALM. No significant differences in the sensory characteristics of the meat were noted. However, the results of the principal component analysis of meat characteristics enabled meat from those steers that consumed fatty acids from olive oil to be differentiated from that of steers that consumed soybean oil. PMID:26585286

  18. Different Disinfectants Efficiency of Fruits and Vegetables Available in Market of

    Directory of Open Access Journals (Sweden)

    Abdollah Dargahi

    2013-11-01

    Full Text Available The fruits and vegetables are carrier microbial flora and in every stage of production, transportation, packaging, storage and sale to consumers are exposed to microbial contamination. Raw fruits and vegetables are suitable place for growing a variety of parasites and bacteria such as Shigella, Pseudomonas aeruginosa and Campylobacter that many of theirs can cause epidemic if the conditions have provide.

  19. Gravimetric Vegetation Water Content Estimation for Corn Using L-Band Bi-Angular, Dual-Polarized Brightness Temperatures and Leaf Area Index

    Directory of Open Access Journals (Sweden)

    Qi Wang

    2015-08-01

    Full Text Available In this study, an algorithm to retrieve the gravimetric vegetation water content (GVWC, % of corn was developed. First, the method for obtaining the optical depth from L-band (1.4 GHz bi-angular, dual-polarized brightness temperatures (TB for short vegetation was investigated. Then, the quantitative relationship between the corn optical depth, corn GVWC and corn leaf area index (LAI was constructed. Finally, using the Polarimetric L-band Microwave Radiometer (PLMR airborne data in the 2012 Heihe Watershed Allied Telemetry Experimental Research (HiWATER project, the Global Land Surface Satellite (GLASS LAI product, the height and areal density of the corn stalks, the corn GVWC was estimated (corn GLASS-GVWC. Both the in situ measured corn GVWC and the corn GVWC retrieved based on the in situ measured corn LAI (corn LAINET-GVWC were used to validate the accuracy of the corn GLASS-GVWC. The results show that the GVWC retrieval method proposed in this study is feasible for monitoring the corn GVWC. However, the accuracy of the retrieval results is highly sensitive to the accuracy of the LAI input parameters.

  20. Limitaciones en la estimación de variables biofísicas en cultivos usando índices de vegetación espectrales: efecto de la densidad del follaje / Limitations in the estimation of biophysical variables in crops using spectral vegetation indexes: foliage density effect

    Scientific Electronic Library Online (English)

    Magali, Odi-Lara; Fernando, Paz-Pellat; Ramón, López-Urrea; José, González-Piqueras.

    2010-11-01

    Full Text Available En cultivos con una densidad alta del follaje, se produce la saturación rápida de la banda del rojo y la reducción de las variaciones en las pendientes de las curvas de igual vegetación (iso-IAF), en las que están basados muchos índices de vegetación (IV). Por ello, es importante el desarrollo de ín [...] dices alternativos que no presenten problemas de saturación y sean fácilmente parametrizados con información de campo. Con este fin se evalúan los patrones temporales (modelo expo-lineal como referencia) de índices espectrales basados en las pendientes de las líneas iso-IAF, así como los de variables biofísicas: biomasa aérea (Bm), cobertura aérea (fv) y altura (h) de dos cultivos con diferente densidad del follaje, alta (sorgo) y media (algodón). Al aplicar un modelo expo-lineal se espera que presenten un patrón bilineal siempre que exista coincidencia de las variables en las fases de inicio y final. En general, las fases exponencial y lineal de la Bm no coinciden con las de fv y h, mostrando diferencias entre las características estructurales y de distribución espacial de la vegetación (fv y h) y la función fotosintética (follaje y biomasa). El cultivo de densidad media presenta patrones bilineales bien caracterizados; en cambio, el de alta densidad muestra una rápida saturación en la fase exponencial de la Bm. Para reducir el problema de saturación, se exploró el uso de la constante aditiva a0 como alternativa de los índices basados en la pendiente. La relación entre la constante aditiva y Bm presentó patrones de tipo expo-lineal doble con problemas en la definición de sus transiciones; las relaciones con la variable fv fueron bilineales, tanto para el cultivo de densidad media como para el de densidad alta, permitiendo una parametrización fácil en campo de los índices de vegetación (uso de fv); con la altura la relación fue lineal-exponencial. Abstract in english High density foliage crops produce the rapid saturation of the red band and reduction of variations in curve slopes of the same vegetation (iso-LAI), on which many vegetation indexes (VI) are based. For this reason, it is important to develop alternative indexes that do not become saturated and that [...] are easily parameterized with information from the field. To this end, temporal patterns of spectral indexes (expo-linear model as reference) were evaluated based on the slopes of the iso-LAI lines, as well as the biophysical variables aerial biomass (Bm), aerial cover (fv) and height (h) of two crops with different foliage density: high (sorghum) and medium (cotton). When an expo-linear model is applied, it is expected that it would have a bi-linear pattern, as long as the variables coincide in their initial and end phases. In general, the Bm exponential and linear phases do not coincide with those of fv and h; this shows that there are differences among the structural characteristics, those of spatial vegetation distribution (fv and h), and photosynthetic function (foliage and biomass). The medium density crop exhibited well-characterized bilinear patterns. In contrast, the high density crop saturated rapidly in the exponential phase of Bm. To reduce the problem of saturation, the use of the additive constant a0 was explored as an alternative to the indexes based on slope. The relationship between the additive constant and Bm exhibited patterns of the double expo-linear type with problems in the definition of its transitions; the relationship with the variable fv were bi-linear, both for the medium density crop and for the high density crop, thus facilitating parameterization the vegetation indexes (use of fv) in the field; with height, the relationship was linear-exponential.

  1. Incorporating different vegetable oils into an aqueous dispersion of hybrid organic nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Samyn, Pieter, E-mail: Pieter.Samyn@fobawi.uni-freiburg.de [Albert-Luedwigs-University Freiburg, Institute for Forest Utilization (Germany); Schoukens, Gustaaf [Ghent University, Department of Textiles (Belgium); Stanssens, Dirk; Vonck, Leo; Van den Abbeele, Henk [Topchim N.V. (Belgium)

    2012-08-15

    Different vegetable oils including soy oil, high-oleic sunflower oil, corn oil, castor oil (CO), rapeseed oil, and hydrogenated CO were added to the imidization reaction of poly(styrene-maleic anhydride) or SMA, with ammonium hydroxide in aqueous medium. The oils favorably reduce viscosity during ammonolysis of the anhydride moieties and increase the maximum solid content of the dispersed imidized SMA to at least 50 wt%, compared to a maximum of 35 wt% for pure imidized SMA. The viscosity of imidized SMA with polyunsaturated oils was generally larger than for monosaturated oils, but it was highest for COs due to high contents of hydroxyl groups. Depending on the oil reactivity, homogeneous or core-shell nanoparticles with 20-60 nm diameters formed. The interactions of oil and organic phase were studied by Fourier-transform infrared spectroscopy, indicating qualitative variances between different oils, the fraction imidized SMA and remaining fraction of ammonolyzed SMA without leakage of oil upon diluting the dispersion and precipitation at low pH. A quantitative analysis with calculation of imide contents, amounts of reacted oil and chemical interactions was made by Fourier-transform-Raman spectroscopy suggesting that most interactions take place around the unsaturated oil moieties and ammonolyzed anhydride.

  2. Incorporating different vegetable oils into an aqueous dispersion of hybrid organic nanoparticles

    International Nuclear Information System (INIS)

    Different vegetable oils including soy oil, high-oleic sunflower oil, corn oil, castor oil (CO), rapeseed oil, and hydrogenated CO were added to the imidization reaction of poly(styrene–maleic anhydride) or SMA, with ammonium hydroxide in aqueous medium. The oils favorably reduce viscosity during ammonolysis of the anhydride moieties and increase the maximum solid content of the dispersed imidized SMA to at least 50 wt%, compared to a maximum of 35 wt% for pure imidized SMA. The viscosity of imidized SMA with polyunsaturated oils was generally larger than for monosaturated oils, but it was highest for COs due to high contents of hydroxyl groups. Depending on the oil reactivity, homogeneous or core–shell nanoparticles with 20–60 nm diameters formed. The interactions of oil and organic phase were studied by Fourier-transform infrared spectroscopy, indicating qualitative variances between different oils, the fraction imidized SMA and remaining fraction of ammonolyzed SMA without leakage of oil upon diluting the dispersion and precipitation at low pH. A quantitative analysis with calculation of imide contents, amounts of reacted oil and chemical interactions was made by Fourier-transform-Raman spectroscopy suggesting that most interactions take place around the unsaturated oil moieties and ammonolyzed anhydride.

  3. Mercury concentration in vegetables of Pakistan irrigated by different water sources

    International Nuclear Information System (INIS)

    Mercury levels were determined in twenty samples of each vegetable i.e., Spinach (Spinacia oleracea), Lettuce (Lactuca sativa), Carrot (Daucus cariota), Capsicum (Capsicum fistulosus), Sweet pea (Lathyrus Odoratus), Potato (Solanum tuberosum) and Cabbage (Brassica oleracea), with a special reference of source of water of irrigation, i.e., tube well water, canal water and municipal sewage water. All the samples of vegetables were collected during the year 2006, 2007 and 2008 from the five districts of Pakistan viz Lahore, Kasur, Multan, Bahawalpur and R.Y. Khan. Statistical analysis such as Test of significance and multiple comparison were applied on the data obtained. The results showed that the concentration of Mercury in vegetables irrigated by canal water, sewage water and tube well water was in the range of 3.1-88.9 ppb and 9.0-130.6 ppb. It can be concluded from this study that the uptake of mercury by vegetables collected from above five districts of Pakistan was in the following order. Leafy vegetables > Root vegetables > seedy vegetables. (author)

  4. Bacterial diversity in the saliva of patients with different oral hygiene indexes

    Scientific Electronic Library Online (English)

    Juliana Vianna, Pereira; Luciana, Leomil; Fabíola, Rodrigues-Albuquerque; José Odair, Pereira; Spartaco, Astolfi-Filho.

    Full Text Available O objetivo do presente estudo foi avaliar a diversidade bacteriana da saliva de pacientes com diferentes índices de higiene bucal através da construção de duas bibliotecas do gene 16S rRNA. Cada biblioteca foi composta por amostras de saliva de pacientes com índice de biofilme dental de Silness-Löe [...] diferenciado, sendo a primeira (A) com índice de 1,0 a 3,0 (denominada de alto índice) e a segunda (B), entre 0 a 0,5 (denominada de baixo índice). O DNA da saliva foi extraído e o gene 16S rRNA foi amplificado, clonado e sequenciado. As sequências obtidas foram comparadas com aquelas armazenadas no GenBank do NCBI e RDP. A saliva de pacientes com alto índice de biofilme dental apresentou cinco gêneros conhecidos: Streptococcus, Granulicatella, Gemella, Veillonella e Peptostreptococcus e 33,3% de bactérias não-cultivadas, agrupados em 23 unidades taxonômicas operacionais (UTOs). A saliva de pacientes com baixo índice de biofilme dental, foi diferente significativamente da primeira (p=0,000) e foi composta de 42 UTOs, distribuídas em 11 gêneros conhecidos: Streptococcus, Granulicatella, Gemella, Veillonella, Oribacterium, Haemophilus, Escherichia, Neisseria, Prevotella, Capnocytophaga, Actinomyces, além de 24,87% de bactérias não-cultivadas. Pode-se concluir que existe maior diversidade bacteriana na saliva de pacientes com baixo índice de biofilme dental em relação a pacientes com alto índice de biofilme dental Abstract in english The objective of the present study was to evaluate the bacterial diversity in the saliva of patients with different oral hygiene indexes using of two 16S rRNA gene libraries. Each library was composed of samples from patients with different averages of the differentiated Silness-Löe biofilm index: t [...] he first library (A) with an index between 1.0 and 3.0 (considered a high index) and the second library (B) between 0 and 0.5 (considered a low index). Saliva DNA was extracted and the 16S rRNA gene was amplified and cloned. The obtained sequences were compared with those stored at NCBI and RDP GenBank. The saliva of patients with high index presented five known genera - Streptococcus, Granulicatella, Gemella, Veillonella and Peptostreptococcus - and 33.3% of nonculturable bacteria grouped into 23 operational taxonomic units (OTUs). The saliva of patients with low index differed significantly from the first library (p=0.000) and was composed of 42 OTUs distributed into 11 known genera - Streptococcus, Granulicatella, Gemella, Veillonella, Oribacterium, Haemophilus, Escherichia, Neisseria, Prevotella, Capnocytophaga, Actinomyces - including 24.87% of nonculturable bacteria. It was possible to conclude that there is greater bacterial diversity in the saliva of patients with low dental plaque in relation to patients with high dental plaque.

  5. Research note: The effect of different indexation scenarios on child poverty in the UK

    OpenAIRE

    De Agostini, Paola; Tasseva, Iva

    2015-01-01

    Using the tax-benefit microsimulation model EUROMOD and Family Resources Survey, we investigate what would have happened to child poverty in the UK in the periods 2010/11-2015/16 and 2015/16-2020/21 under a range of different indexation scenarios of children's benefits. We find that between 2010/11 and 2015/16 both the relative and absolute child poverty rates would have been lower if children's benefits were uprated by RPI or if the government had introduced the Child Tax Credit uprating pac...

  6. ASSESSMENT OF ACCURACY OF PRECIPITATION INDEX (SPI DETERMI-NED BY DIFFERENT PROBABILITY DISTRIBUTIONS

    Directory of Open Access Journals (Sweden)

    Edward G?siorek

    2014-11-01

    Full Text Available The use of different calculating methods to compute the standardized precipitation index (SPI results in various approximations. Methods based on normal distribution and its transformations, as well as on gamma distribution, give similar results and may be used equally, whereas the lognormal distribution fitting method is significantly discrepant, especially for extreme values of SPI. Therefore, it is problematic which method gives the distribution optimally fitted to empirical data. The aim of this study is to categorize the above mentioned methods according to the degree of approximation to empirical data from the Observatory of Agro- and Hydrometeorology in Wroc?aw-Swojec from 1964–2009 years.

  7. How does feed with different levels of vegetable origin affect the sensory quality of ice storage Rainbow trout (Oncorhynchus mykiss)?

    DEFF Research Database (Denmark)

    Hyldig, Grethe; Nielsen, Henrik Hauch

    Background Fish from the aquaculture sector make up a steep raising share of the total fish consumed and play in that respect an essential role. The most important farmed fish in Denmark is rainbow trout (Oncorhynchus mykiss). However the aquaculture sector, raising fish species which are primarily carnivores, is facing major challenges as a consequence of the limited access in future sustainable resources of wild fish or other sea living organisms from a lower trophic level for feed production. Consequently, alternative feeding regimes are now considered e.g. use of components of vegetable origin such as soy oil or rapeseed oil combined with vegetable proteins. Such a change in feeding regime will result in a “green fish” and may affect flesh quality and eating quality. The objective was to study the effect of vegetable based feed on sensory of ice storage farmed rainbow trout. Experimental design and methods Feed trials Rainbow trout were farmed in tanks at Biomar A/S, Hirtshals and fed on six different diets covering only marine, only vegetables and mixture of marine and vegetable feeds. Trout for the quality study were slaughtered, vacuum-packed and stored at -80°C until analysis. Sensory Quality Changes in sensory quality were determined by objective descriptive sensory methods using profiling carried out by a trained panel. The fish samples were thawed and ice storage for 3, 5, 7 and 12 days. Results The sensory characterization of the trout feed with 100% marine and 100% vegetable feed showed after 3 days of ice storage that the trout feed with marine fed were more firm, juicy and the texture was more flacky that trout feed with vegetable feed. This sensory difference increased with increasing ice storage.

  8. Factors affecting the wettability of different surface materials with vegetable oil at high temperatures and its relation to cleanability

    DEFF Research Database (Denmark)

    Ashokkumar, Saranya; Adler-Nissen, Jens; Møller, Per

    2012-01-01

    The main aim of the work was to investigate the wettability of different surface materials with vegetable oil (olive oil) over the temperature range of 25–200°C to understand the differences in cleanability of different surfaces exposed to high temperatures in food processes. The different surface materials investigated include stainless steel (reference), PTFE (polytetrafluoroethylene), silicone, quasicrystalline (Al, Fe, Cr) and ceramic coatings: zirconium oxide (ZrO2), zirconium nitride (ZrN)...

  9. Effects of vegetation structure on biomass accumulation in a Balanced Optimality Structure Vegetation Model (BOSVM v1.0

    Directory of Open Access Journals (Sweden)

    Z. Yin

    2014-05-01

    Full Text Available A myriad of interactions exist between vegetation and local climate for arid and semi-arid regions. Vegetation function, structure and individual behavior have large impacts on carbon–water–energy balances, which consequently influence local climate variability that, in turn, feeds back to the vegetation. In this study, a conceptual vegetation structure scheme is formulated and tested in the new Balanced Optimality Structure Vegetation Model (BOSVM to explore the importance of vegetation structure and vegetation adaptation to water stress on equilibrium biomass states. Surface energy, water and carbon fluxes are simulated for a range of vegetation structures across a precipitation gradient in West Africa and optimal vegetation structures that maximize biomass for each precipitation regime are determined. Two different strategies of vegetation adaptation to water stress are included. Under dry conditions vegetation tries to maximize the water use efficiency and leaf area index as it tries to maximize carbon gain. However, a negative feedback mechanism in the vegetation–soil water system is found as the vegetation also tries to minimize its cover to optimize the surrounding bare ground area from which water can be extracted, thereby forming patches of vertical vegetation. Under larger precipitation, a positive feedback mechanism is found in which vegetation tries to maximize its cover as it then can reduce water loss from bare soil while having maximum carbon gain due to a large leaf area index. The competition between vegetation and bare soil determines a transition between a "survival" state to a "growing" state.

  10. Predicting vegetation water content in wheat using normalized difference water indices derived from ground measurements.

    Science.gov (United States)

    Wu, Chaoyang; Niu, Zheng; Tang, Quan; Huang, Wenjiang

    2009-05-01

    Vegetation water content (VWC) is an important variable for both agriculture and forest fire management. Remote sensing technology offers an instantaneous and non-destructive method for VWC assessment provided we can relate in situ measurements of VWC to spectral reflectance in a reliable way. In this paper, based on radiative transfer models, three new normalized difference water indices (NDWI) are proposed for VWC [fuel moisture content (FMC), and equivalent water thickness (EWT)] estimation, taking both leaf internal structure and dry matter content into account. Reflectance at 1,200, 1,450 and 1,940 nm were selected and normalized with reflectance at 860 nm to establish three water indices, NDWI(1200), NDWI(1450) and NDWI(1940). Good correlations were observed between FMC (R (2) = 0.65-0.80) and EWT (both at the leaf scale, R (2) = 0.75-0.81 for EWT(L) and at the canopy scale, R (2) = 0.80-0.83 for EWT(C)) at various stages of wheat crop development. PMID:19242776

  11. Integration of fermentative biohydrogen with methanogenesis from fruit–vegetable waste using different pre-treatments

    International Nuclear Information System (INIS)

    Highlights: • An optimal pre-treatment for FVW used in two-stage fermentation is presented. • The spectroscopic characteristics of soluble metabolites were analysed. • The effluents were characterised by EEM with a parallel factor analysis. - Abstract: Fruit–vegetable waste was subjected to three different pre-treatments to enrich the two-stage biofuel production potential. The fluorescence excitation–emission matrix (EEM) spectra coupled with parallel factor (PARAFAC) analysis and fluorescence regional integration analysis were utilised to investigate dissolved organic matter degradation during two-stage fermentation process. The results showed that compared with that of alkali and enzyme pre-treatments, the acid pre-treatment resulted in the maximum biogas production rates and proportion in the hydrogenogenic stage (10.11 mL/h, 41.2% hydrogen) when combined with the methanogenic process (4.67 mL/h, 76.1% methane). In addition, the analysis of soluble metabolites composition indicated that both ethanol- and butyric acid-type fermentation processes had taken place as a result of acid pre-treatment, whereas only butyric acid-type fermentation resulted from alkali and enzyme pre-treatments. The PARAFAC analysis modelling of the EEM spectra revealed three fluorescent components in the effluents of three fermentation stages and assumed that the projected characteristic value may be used as a rapidly obtained indicator for substrate degradation and system stability of a two-stage biofuel production process

  12. COMPARISON OF BIODIESEL PRODUCTIVITIES OF DIFFERENT VEGETABLE OILS BY ACIDIC CATALYSIS

    Directory of Open Access Journals (Sweden)

    AYTEN SAGIROGLU

    2011-03-01

    Full Text Available Biodiesel has become a subject which increasingly attracts worldwide attention because of its environmental benefits, biodegradability and renewability. Biodiesel production typically involves the transesterification of a triglyceride feedstock with methanol or other short-chain alcohols. This paper presents a study of transesterification of various vegetable oils, sunflower, safflower, canola, soybean, olive, corn, hazelnut and waste sunflower oils, with the acidic catalyst. Under laboratory conditions, fatty acid methyl esters (FAME were prepared by using methanol in the presence of 1.85% hydrochloric acid at 100 °C for 1 h and 25 °C for 3 h. The analyses of biodiesel were carried out by gas chroma¬tography and thin layer chromatography. Also, biodiesel productivities (% were determined on basis of the ratio of ester to oil content (w/w. The biodiesel productivities for all oils were found to be about 80% and about 90% at 25 and 100 °C, respectively. Also, the results showed that the yield of biodiesel depended on temperature for some oils, including canola, sunflower, safflower oils, but it was not found significant differences among all of the oil types on biodiesel productivities.

  13. Summary of the especies of Spanish vegetation sensitive to different pollutants

    International Nuclear Information System (INIS)

    A detail literature review of the sensitivity of the species of Spanish vegetation to various pollutants was made. An impact scale was created to describe the qualitative degree of sensitivity to which each specie is affected by major atmospheric pollutants: very sensitive, sensitive, intermediate sensitive and resistent. This type of study, combined with studies of emission, concentration and dispersion of air pollution, is of great interest to evaluate the environmental impact to the vegetation community. (author) 45 refs

  14. Effect of novel ultrasound based processing on the nutrition quality of different fruit and vegetable juices.

    Science.gov (United States)

    Khandpur, Paramjeet; Gogate, Parag R

    2015-11-01

    Increasing consumer awareness regarding the health benefits of different nutrients in food have led to the requirement of assessing the effect of food processing approaches on the quality attributes. The present work focuses on understanding the effects of novel approaches based on the use of ultrasound and ultraviolet irradiations on the nutritional quality of different fruit and vegetable juices (orange, sweet lime, carrot and spinach juices) and its comparison with the conventional thermal pasteurization operated at 80°C for 10 min. The ultrasound sterilization parameters were maintained at ultrasound frequency of 20 kHz and power of 100 W with treatment time as 15 min. For the case of ultraviolet irradiations, 2 UVC lamps (254 nm) of 8 W were placed in parallel on either sides of the reactor. The treated juices were analyzed for total phenol content, antioxidant activity, vitamin C, carbohydrates etc. It has been established that ultrasound processed juice retained most of the nutrient components to higher extent in comparison to all the other techniques used in the work. Combination of ultrasound and ultraviolet irradiations used to achieve an effective decontamination of juices (recommended 5 log reduction of microorganisms) also retained nutrients to a higher level in comparison to the thermal method; however some losses were observed as compared to the use of only ultrasound which could be attributed to inefficient heat exchange in the combined approach. A scale up attempt was also made for treatment of spinach juice using ultrasonic reactors and analysis for quality attributes confirmed that the juice satisfied the criteria of required nutrient contents for 18 days shelf life trial in refrigerated storage conditions. The present work has clearly established the usefulness of ultrasound based treatment in maintaining the nutritional quality of beverages while giving enhanced shelf life as compared to the conventional approaches. PMID:26186829

  15. Growth and photosynthetic capacity in two woody species of cerrado vegetation under different radiation availability

    Scientific Electronic Library Online (English)

    Carlos Cesar, Ronquim; Carlos Henrique B. de A., Prado; Nádia Figueiredo de, Paula.

    2003-03-01

    Full Text Available Duas espécies de cerrado (Copaifera langsdorffii e Eriotheca gracilipes) foram cultivadas sob três diferentes condições de radiação (100, 80 e 30% de transmitância). A radiação solar plena proporcionou as condições mais favoráveis para o desenvolvimento das espécies: maior acúmulo de biomassa total, [...] maior área foliar total, maior fotossíntese potencial por copa expressa em área ou em massa e maior capacidade fotossintética expressa em área foliar. Somente os valores de capacidade fotossintética expressa em massa foram maiores sob baixa radiação (80 e 30% de transmitância) para ambas as espécies. As diferenças de biomassa acumulada apareceram mais claramente após os 4 meses de plantio, mas a relação massa seca raiz/parte aérea e a altura foram mantidas independentes da radiação disponível para ambas as espécies. Sob 100% de transmitância estas espécies apresentaram um balanço de carbono mais positivo e condições mais favoráveis para suprir as duas principais demandas neste estágio do ciclo de vida da planta: o crescimento e a defesa. Abstract in english Seedlings of two woody species of cerrado vegetation, Copaifera langsdorffii and Eriotheca gracilipes, were studied under three different radiation availability (100, 80 and 30% transmittance). Full solar radiation brought about more biomass, higher total leaf area, higher maximal photosynthesis per [...] crown on area or on mass bases and higher photosynthetic capacity on area bases. Only the photosynthetic capacity values on leaf mass bases were higher in both species under low radiation availability (80 and 30% transmittance). The differences of accumulated biomass appeared more clearly after 4 months of sowing but the root/shoot dry biomass ratio and height were maintained constant for both species independently of the available radiation. Cultivated under full solar radiation both species will be able to cover more suitable the two processes during seedling's phase: growth and defense.

  16. The computation of dynamic fractional difference parameter for S&P500 index

    Science.gov (United States)

    Pei, Tan Pei; Cheong, Chin Wen; Galagedera, Don U. A.

    2015-10-01

    This study evaluates the time-varying long memory behaviors of the S&P500 volatility index using dynamic fractional difference parameters. Time-varying fractional difference parameter shows the dynamic of long memory in volatility series for the pre and post subprime mortgage crisis triggered by U.S. The results find an increasing trend in the S&P500 long memory volatility for the pre-crisis period. However, the onset of Lehman Brothers event reduces the predictability of volatility series following by a slight fluctuation of the factional differencing parameters. After that, the U.S. financial market becomes more informationally efficient and follows a non-stationary random process.

  17. Monitoring of vegetation dynamics and assessing vegetation response to drought in the Iberian Peninsula

    International Nuclear Information System (INIS)

    Monitoring the vegetation activity over long time-scales is necessary to discern ecosystem response to climate variability. Spatial and temporally consistent estimates of the biophysical variables such as fractional vegetation cover (FVC) and leaf area index (LAI) have been obtained in the context of DULCINEA Project. We used long-term monthly climate statistics to build simple climatic indices (SPI, moisture index) at different time scales. From these indices, we estimated that the climatic disturbances affected both the growing season and the total amount of vegetation. This implies that the anomaly of vegetation cover is a good indicator of moisture condition and can be an important data source when used for detecting an monitoring drought in the Iberian Peninsula. The impact of climate variability on the vegetation dynamics has shown not to be the same for every region. We concluded that the relationships between vegetation anomaly and moisture availability are significant for the arid and semiarid areas. (Author) 6 refs.

  18. Monitoring of vegetation dynamics and assessing vegetation response to drought in the Iberian Peninsula

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Haro, F. J.; Moreno, A.; Perez-Hoyos, A.; Gilabert, M. A.; Melia, J.; Belda, F.; Poquet, D.; Martinez, B.; Verger, A.

    2009-07-01

    Monitoring the vegetation activity over long time-scales is necessary to discern ecosystem response to climate variability. Spatial and temporally consistent estimates of the biophysical variables such as fractional vegetation cover (FVC) and leaf area index (LAI) have been obtained in the context of DULCINEA Project. We used long-term monthly climate statistics to build simple climatic indices (SPI, moisture index) at different time scales. From these indices, we estimated that the climatic disturbances affected both the growing season and the total amount of vegetation. This implies that the anomaly of vegetation cover is a good indicator of moisture condition and can be an important data source when used for detecting an monitoring drought in the Iberian Peninsula. The impact of climate variability on the vegetation dynamics has shown not to be the same for every region. We concluded that the relationships between vegetation anomaly and moisture availability are significant for the arid and semiarid areas. (Author) 6 refs.

  19. Adapting Extension Food Safety Programming for Vegetable Growers to Accommodate Differences in Ethnicity, Farming Scale, and Other Individual Factors

    Science.gov (United States)

    Kline, Terence R.; Kneen, Harold; Barrett, Eric; Kleinschmidt, Andy; Doohan, Doug

    2012-01-01

    Differences in vegetable production methods utilized by American growers create distinct challenges for Extension personnel providing food safety training to producer groups. A program employing computers and projectors will not be accepted by an Amish group that does not accept modern technology. We have developed an outreach program that covers…

  20. Adapting Extension Food Safety Programming for Vegetable Growers to Accommodate Differences in Ethnicity, Farming Scale, and Other Individual Factors

    Science.gov (United States)

    Kline, Terence R.; Kneen, Harold; Barrett, Eric; Kleinschmidt, Andy; Doohan, Doug

    2012-01-01

    Differences in vegetable production methods utilized by American growers create distinct challenges for Extension personnel providing food safety training to producer groups. A program employing computers and projectors will not be accepted by an Amish group that does not accept modern technology. We have developed an outreach program that covers…

  1. Effects of adding bentonite to different substrates on vegetative growth and yield of snap beans (Phaseulus vulgaris L.

    Directory of Open Access Journals (Sweden)

    P. Aghdak

    2010-12-01

    Full Text Available To study the effects of adding a superabsorbent (bentonite to different substrates on the vegetative growth and yield of snap beans, two randomized complete block design experiments with 4 replications were conducted at Greenhouse of Isfahan University of Technology. In the first experiment, 9 treatments including rice hull, saw dust, sand and their combinations, with 10 and 20% superabsorbent (v/v were used. The results showed that the highest stem length, number of nodes and leaves, shoot fresh weight and pod number were observed using rice hull (90%+superabsorbent (10%. The lowest vegetative growth was related to treatments containing sand and superabsorbent. Increasing superabsorbent from 10 to 20% reduced vegetative growth parameters in most cases. Based on the results of the first experiment, sand treatment was deleted and in the second experiment rice hull, saw dust, perlite and their combinations with 5 and 10% superabsorbent were used. The results showed that the highest plant height, number of nodes and leaves, plant dry weight, branch number and yield were obtained in perlite (95%+superabsorbent (5% and pure perlite. Adding 5 and 10% superabsorbent to rice hull and saw dust caused a significant increase in the vegetative growth. This increase was higher for 10% superabsorbent compared to 5% superabsorbent. Finally, the results showed that adding 10% superabsorbent to rice hull and saw dust increased vegetative growth and yield, while it decreased the loss of nutrient solution.

  2. Development and testing of an index of biotic integrity based on submersed and floating vegetation and its application to assess reclamation wetlands in Alberta's oil sands area, Canada.

    Science.gov (United States)

    Rooney, Rebecca C; Bayley, Suzanne E

    2012-01-01

    We developed and tested a plant-based index of biological integrity (IBI) and used it to evaluate the existing reclamation wetlands in Alberta's oil sands mining region. Reclamation plans call for >15,000 ha of wetlands to be constructed, but currently, only about 25 wetlands are of suitable age for evaluation. Reclamation wetlands are typically of the shallow open water type and range from fresh to sub-saline. Tailings-contaminated wetlands in particular may have problems with hydrocarbon- and salt-related toxicity. From 60 initial candidate metrics in the submersed aquatic and floating vegetation communities, we selected five to quantify biological integrity. The IBI included two diversity-based metrics: the species richness of floating vegetation and the percent of total richness contributed by Potamogeton spp. It also included three relative abundance-based metrics: that of Ceratophyllum demersum, of floating leafed species and of alkali-tolerant species. We evaluated the contribution of nonlinear metrics to IBI performance but concluded that the correlation between IBI scores and wetland condition was not improved. The method used to score metrics had an influence on the IBI sensitivity. We conclude that continuous scoring relative to the distribution of values found in reference sites was superior. This scoring approach provided good sensitivity and resolution and was grounded in reference condition theory. Based on these IBI scores, both tailings-contaminated and tailings-free reclamation wetlands have significantly lower average biological integrity than reference wetlands (ANOVA: F(2,59) = 34.7, p = 0.000000000107). PMID:21484300

  3. Adherence to a vegetable-fruit-soy dietary pattern or the Alternative Healthy Eating Index is associated with lower hip fracture risk among Singapore Chinese.

    Science.gov (United States)

    Dai, Zhaoli; Butler, Lesley M; van Dam, Rob M; Ang, Li-Wei; Yuan, Jian-Min; Koh, Woon-Puay

    2014-04-01

    Data on overall dietary pattern and osteoporotic fracture risk from population-based cohorts are limited, especially from Asian populations. This study examined the relation between overall diet and hip fracture risk by using principal components analysis (PCA) to identify dietary pattern specific to the study population and by using the Alternative Healthy Eating Index (AHEI) 2010 to assess dietary quality. The Singapore Chinese Health Study is a prospective population-based cohort that enrolled 63,257 Chinese men and women (including both pre- and postmenopausal women) aged 45-74 y between 1993 and 1998 in Singapore. Habitual diet was assessed by using a validated food-frequency questionnaire. Two dietary patterns, the vegetable-fruit-soy (VFS) pattern and the meat-dim-sum (MDS) pattern, were derived by PCA. Overall dietary quality was assessed according to the AHEI 2010, which was defined a priori for chronic disease prevention. A Cox regression model was applied with adjustment for potential confounders. In both genders, higher scores for the VFS pattern and the AHEI 2010 were associated with lower risk of hip fracture in a dose-dependent manner (all P-trend ? 0.008). Compared with the lowest quintile, participants in the highest quintile had a 34% reduction in risk (HR: 0.66; 95% CI: 0.55, 0.78) for the VFS pattern and a 32% reduction in risk (HR: 0.68; 95% CI: 0.58, 0.79) for the AHEI 2010. The MDS pattern score was not associated with hip fracture risk. An Asian diet rich in plant-based foods, namely vegetables, fruit, and legumes such as soy, may reduce the risk of hip fracture. PMID:24572035

  4. Accuracy of the Temperature-Vegetation Dryness Index using MODIS under water-limited vs. energy-limited evapotranspiration conditions

    DEFF Research Database (Denmark)

    Garcia, Monica; Ferna?ndez, N.; Villagarci?a, L.; Domingo, F.; Puigdefa?bregas, J.; Sandholt, Inge

    2014-01-01

    types and climatic variables in the region, or the algorithm to extract hydrological boundaries from the images. The TVDI was compared with eddy covariance (EC) data from two shrublands with different climatic controls for ?E in South Spain. Evaluations showed that it could be used to estimate the water...

  5. A tobacco cDNA reveals two different transcription patterns in vegetative and reproductive organs

    Directory of Open Access Journals (Sweden)

    I. da Silva

    2002-08-01

    Full Text Available In order to identify genes expressed in the pistil that may have a role in the reproduction process, we have established an expressed sequence tags project to randomly sequence clones from a Nicotiana tabacum stigma/style cDNA library. A cDNA clone (MTL-8 showing high sequence similarity to genes encoding glycine-rich RNA-binding proteins was chosen for further characterization. Based on the extensive identity of MTL-8 to the RGP-1a sequence of N. sylvestris, a primer was defined to extend the 5' sequence of MTL-8 by RT-PCR from stigma/style RNAs. The amplification product was sequenced and it was confirmed that MTL-8 corresponds to an mRNA encoding a glycine-rich RNA-binding protein. Two transcripts of different sizes and expression patterns were identified when the MTL-8 cDNA insert was used as a probe in RNA blots. The largest is 1,100 nucleotides (nt long and markedly predominant in ovaries. The smaller transcript, with 600 nt, is ubiquitous to the vegetative and reproductive organs analyzed (roots, stems, leaves, sepals, petals, stamens, stigmas/styles and ovaries. Plants submitted to stress (wounding, virus infection and ethylene treatment presented an increased level of the 600-nt transcript in leaves, especially after tobacco necrosis virus infection. In contrast, the level of the 1,100-nt transcript seems to be unaffected by the stress conditions tested. Results of Southern blot experiments have suggested that MTL-8 is present in one or two copies in the tobacco genome. Our results suggest that the shorter transcript is related to stress while the larger one is a flower predominant and nonstress-inducible messenger.

  6. A tobacco cDNA reveals two different transcription patterns in vegetative and reproductive organs

    Scientific Electronic Library Online (English)

    I. da, Silva; P.C.S., Angelo; J.B., Molfetta; M.T., Ferraz; L.L.P. da, Silva; G.H., Goldman; M.H.S., Goldman.

    2002-08-01

    Full Text Available In order to identify genes expressed in the pistil that may have a role in the reproduction process, we have established an expressed sequence tags project to randomly sequence clones from a Nicotiana tabacum stigma/style cDNA library. A cDNA clone (MTL-8) showing high sequence similarity to genes e [...] ncoding glycine-rich RNA-binding proteins was chosen for further characterization. Based on the extensive identity of MTL-8 to the RGP-1a sequence of N. sylvestris, a primer was defined to extend the 5' sequence of MTL-8 by RT-PCR from stigma/style RNAs. The amplification product was sequenced and it was confirmed that MTL-8 corresponds to an mRNA encoding a glycine-rich RNA-binding protein. Two transcripts of different sizes and expression patterns were identified when the MTL-8 cDNA insert was used as a probe in RNA blots. The largest is 1,100 nucleotides (nt) long and markedly predominant in ovaries. The smaller transcript, with 600 nt, is ubiquitous to the vegetative and reproductive organs analyzed (roots, stems, leaves, sepals, petals, stamens, stigmas/styles and ovaries). Plants submitted to stress (wounding, virus infection and ethylene treatment) presented an increased level of the 600-nt transcript in leaves, especially after tobacco necrosis virus infection. In contrast, the level of the 1,100-nt transcript seems to be unaffected by the stress conditions tested. Results of Southern blot experiments have suggested that MTL-8 is present in one or two copies in the tobacco genome. Our results suggest that the shorter transcript is related to stress while the larger one is a flower predominant and nonstress-inducible messenger.

  7. The effect of cutting regime on yield of sorghum in different climatic (vegetation seasons

    Directory of Open Access Journals (Sweden)

    Darko Uher

    2005-01-01

    Full Text Available Forage could be produced on natural grasslands, leys or arable land, but in lowland and in dry areas short season forage crops should be interpolated due to instability of yields from grasslands. Using that pattern, it is possible to better utilize the potential of arable land and the energy of the sun instead of leaving the fields empty (3-8 months, and to produce high yield of quality forage. Sorghum hybrids fit well in that system of forage production on family farms. It could be sown after harvesting of winter and early sown spring crops, and utilized in few cuts during a second part of summer, until the beginning of autumn and appearance of the first frost. Furthermore, it could ensure good yields of quality green forage and the rest quantity could be ensilaged. In that way higher yields of quality forage per hectare could be provided during vegetation season. The experiment was conducted at Maksimir experimental field, Faculty of Agriculture University of Zagreb. The aim of this research was to determine green mass yield (GMY and dry matter yield (DMY of sorghum (cv. Grazer N, at different cutting regime in two various seasons (dry and wet summer. The highest GMY and DMY were obtained when sorghum was cut 2 times at 200 cm height in 2002 and 2003 experimental years. Climatic conditions were better in the year 2002, so in that year GMY varied from 85.2 to 100.7 t/ha, while DMY varied from 18.7 to 31.0 t/ha. In the experimental year 2003 GMY varied from 58.6 to 86.6 t/ha, while DMY varied from 14.6 to 26.6 t/ha. Even in such unfavorable year, as 2003 was, sorghum (cv. Grazer N expressed its great potential for continuing utilization in summer and early autumn.

  8. Soil Organic Carbon in Mangrove Ecosystems with Different Vegetation and Sedimentological Conditions

    Directory of Open Access Journals (Sweden)

    Naohiro Matsui

    2015-11-01

    Full Text Available A large number of studies have been conducted on organic carbon (OC variation in mangrove ecosystems. However, few have examined its relationship with soil quality and stratigraphic condition. Mangrove OC characteristics would be explicitly understood if those two parameters were taken into account. The aim of this study was to examine mangrove OC characteristics qualitatively and quantitatively after distinguishing mangrove OC from other OC. Geological survey revealed that the underground of a mangrove ecosystem was composed of three layers: a top layer of mangrove origin and two underlying sublayers of geologic origin. The underlying sublayers were formed from different materials, as shown by X-ray fluorescence analysis. Despite a large thickness exceeding 700 cm in contrast to the 100 cm thickness of the mangrove mud layer, the sublayers had much lower OC stock. Mangrove mud layer formation started from the time of mangrove colonization, which dated back to between 1330 and 1820 14C years BP, and OC stock in the mangrove mud layer was more than half of the total OC stock in the underground layers, which had been accumulating since 7200 14C years BP. pH and redox potential (Eh of the surface soils varied depending on vegetation type. In the surface soils, pH correlated to C% (r = ?0.66, p < 0.01. C/N ratios varied widely from 3.9 to 34.3, indicating that mangrove OC had various sources. The pH and Eh gradients were important factors affecting the OC stock and the mobility/uptake of chemical elements in the mangrove mud layer. Humic acids extracted from the mangrove mud layer had relatively high aliphatic contents, in contrast with the carboxylic acid rich sublayers, indicating that humification has not yet progressed in mangrove soil.

  9. LEAF AREA INDEX IN WINTER WHEAT: RESPONSE ON SEED RATE AND NITROGEN APPLICATION BY DIFFERENT VARIETIES

    Directory of Open Access Journals (Sweden)

    M BAVEC

    2007-12-01

    Full Text Available The most important photosynthesis acceptor – leaf area vary among cultivation measures and it is limited factor for creating exact growth models in common winter wheat. The objective of this study was to investigate changes of leaf area index (LAI affected by agricultural treatments – 4 sowing rates and 9 nitrogen treatments based on fertilising rates, target values based on soil mineral nitrogen and plant sap tests target values including different varieties. Increasing sowing rates from 350 to 800 viable seeds m-2 increased LAI at EC 75 stage from 2.9 to 5.5, where LAI 4.1 at 500 seeds m-2 did not vary between lower and higher rates; also at EC 85 stage LAIs did not differ significantly. At EC 75 stage LAI differed among control and nitrogen treatments from 1.0 to 6.5 and at EC 85 stage from 0.1 to 2.4, with differences in interaction among varieties. Higher nitrogen rates for first and second top dressing increased LAI in both stages compared without dressing treatments. Due to significant differences among LAI as consequence of production system, we suggest to take this into account in every prediction and modelling of growth in winter wheat.

  10. SMAPVEX12 Vegetation Water Content Map V001

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains the vegetation water content map derived by calculating Normalized Difference Water Index (NDWI) from SPOT and RapidEye satellite imagery as...

  11. SMAPVEX12 Vegetation Water Content Map V001

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set contains the vegetation water content map derived by calculating Normalized Difference Water Index (NDWI) from SPOT and RapidEye satellite imagery as...

  12. Effects of vegetation structure on biomass accumulation in a Balanced Optimality Structure Vegetation Model (BOSVM v1.0

    Directory of Open Access Journals (Sweden)

    Z. Yin

    2013-09-01

    Full Text Available A myriad of interactions exist between vegetation and local climate for arid and semi-arid regions. Vegetation function, structure and individual behavior have large impacts on carbon-water-energy balances, which consequently influence local climate variability that, in turn, feeds back to the vegetation. In this study, a conceptual vegetation structure scheme is formulated and tested in a new carbon-water-energy coupled model to explore the importance of vegetation structure and vegetation adaptation to water stress on equilibrium biomass states. Surface energy, water and carbon fluxes are simulated for a range of vegetation structures across a precipitation gradient in West Africa and optimal vegetation structures that maximizes biomass for each precipitation regime are determined. Two different strategies of vegetation adaptation to water stress are included. Under dry conditions vegetation tries to maximize the Water Use Efficiency and Leaf Area Index as it tries to maximize carbon gain. However, an important negative feedback mechanism is found as the vegetation also tries to minimize its cover to optimize the surrounding bare ground area from which water can be extracted, thereby forming patches of vertical vegetation. Under larger precipitation, a positive feedback mechanism is found in which vegetation tries to maximize its cover as it then can reduce water loss from bare soil while having maximum carbon gain due to a large Leaf Area Index. The competition between vegetation and bare soil determines a transition between a "survival" state to a "growing" state.

  13. [K fertility and K deficit index of aquic brown soil under different fertilization systems].

    Science.gov (United States)

    Yu, Wan-Tai; Jiang, Zi-Shao; Shen, Shan-Min; Zhang, Lu

    2007-10-01

    A 15-year fertilization experiment was conducted on an aquic brown soil to study the variations of its K fertility and the index of K deficit under different fertilization systems. The results indicated that no K application accelerated the depletion of soil K, representing a certain decrease of soil available and slow-release K. Applying K alone could not keep soil K in balance, still having a decrease of soil available and slow-release K. The application of recycled compost combined with appropriate amount of fertilizer K could compensate soil K expenditure to a certain degree, and keep the concentrations of soil available and slow-release K somewhat constant. The statistic analysis on the past years test results showed that the critical values of soil available K in corn- and soybean fields obtained by crossing method were all 73 mg x kg(-1). PMID:18163304

  14. Estimación de la capacidad de carga animal en agostaderos usando un índice de vegetación de pendientes normalizadas / Animal carrying capacity estimation in rangelands using a normalized slopes vegetation index

    Scientific Electronic Library Online (English)

    Adán, Villa-Herrera; Fernando, Paz-Pellat; María J., Pérez-Hernández; Camerino, Rojas-Montes; Misael, Rodríguez Arvizu; Sandra, Ortiz-Acosta; Marcos, Casiano-Domínguez; Heriberto, Díaz-Solís.

    2014-09-01

    Full Text Available La estimación de la capacidad de carga animal es un requisito para el manejo ganadero sustentable, por lo que es necesario el desarrollo de marcos teóricos y experimentales innovadores que permitan realizar esta tarea en términos operacionales y a bajo costo. El uso de sensores remotos ofrece una al [...] ternativa que debe explorarse a profundidad para conocer sus limitaciones. Bajo esta perspectiva, en este trabajo se analiza la situación de la utilización de información de campo de reflectancias en una o dos visitas al mismo sitio, por lo que se expandió el marco teórico asociado a los patrones espectrales de las líneas de igual vegetación en el espacio espectral de las bandas del rojo e infrarrojo cercano; esto permitió desarrollar un índice de vegetación de pendientes normalizadas con una relación lineal con el índice de área foliar y la biomasa aérea verde de la vegetación. Esta relación fue validada usando datos de diferentes experimentos, obteniéndose resultados adecuados. La metodología desarrollada bajo una perspectiva de la estimación de la capacidad de carga animal en los pastizales y matorrales del estado de Coahuila fue evaluada usando la información generada en la campaña de muestreo del 2009-2010, que se realizó en 24 sitios de 1.5 km x 1.5 km. Los resultados mostraron, a pesar de algunos problemas experimentales, que es posible realizar estimaciones confiables de la capacidad de carga usando sensores remotos. Abstract in english Animal carrying capacity estimation is a prerequisite for sustainable livestock management, so that the development of theoretical and innovator experimental frameworks to perform this task in operational terms and at low cost is needed. The use of remote sensing offers an alternative which must be [...] deeply explored to know its limitations. Under this perspective, in this study the use of field information of reflectances is analyzed in one or two visits to the same site by which the theoretical framework associated with the spectral patterns of vegetation isolines in spectral space of the bands of red and near infrared was expanded; this allowed developing a normalized slopes vegetation index with a linear relationship with the leaf area index and green aboveground biomass of vegetation. This relationship was validated using data from different experiments, obtaining suitable results. The methodology developed under a perspective of animal carrying capacity estimation in grasslands and scrublands of the state of Coahuila was evaluated using information generated in the sampling campaign of 2009-2010, which was conducted at 24 sites of 1.5 x 1.5 km. The results showed that, despite some experimental problems, it is possible to make reliable estimations of carrying capacity using remote sensing.

  15. Correlação espacial do índice de vegetação (NDVI) de imagem Landsat/ETM+ com atributos do solo / Spatial correlation of the vegetation index (NDVI) of a Landsat/ETM+ images with soil attributes

    Scientific Electronic Library Online (English)

    Fabricio V., Zanzarini; Teresa C. T., Pissarra; Flavia J. C., Brandão; Daniel D. B., Teixeira.

    2013-06-01

    Full Text Available As tecnologias de agricultura de precisão, como o uso da variabilidade espacial dos atributos do solo, vêm sendo muito estudadas para a cultura de cana-de-açúcar. Dentre essas tecnologias se destaca o uso de índices de vegetação derivados de produtos de sensoriamento remoto, como poderosas ferrament [...] as indicadoras do desenvolvimento da vegetação. Objetivou-se, neste estudo, analisar a variabilidade espacial dos teores de argila, fósforo e o pH de um Latossolo Vermelho-amarelo em área com produção de cana-de-açúcar e correlacioná-los com o índice espectral de vegetação (NDVI). Foram estudados, a partir de uma malha georreferenciada, os atributos do solo (argila, fósforo e pH) e gerados mapas de variabilidade espacial. Para esses mesmos locais calculou-se o NDVI possibilitando, além do mapeamento deste índice, a avaliação da correlação espacial entre este e as demais propriedades em estudo. A argila e o teor de fósforo apresentaram correlação espacial positiva com o NDVI enquanto nenhuma correlação espacial foi observada com o pH. A imagem do sensor ETM+ do satélite Landsat 5 utilizada neste estudo em relação ao NDVI, apresentou boa aplicação para observar a variabilidade espacial dos atributos estudados. Abstract in english The precision agriculture technologies such as the spatial variability of soil attributes have been widely studied mostly with sugarcane. Among these technologies have been recently highlighted the use of the vegetation index derived from remote sensing products, such as powerful tools indicating th [...] e development of vegetation. This study aimed to analyze the spatial variability of clay content, pH and phosphorus in an Oxisol in an area with sugarcane production, and correlate with the Normalized Difference Vegetation Index (NDVI). The georeferenced grid was created for the soil properties (clay, phosphorus and pH) and generated the maps of spatial variability. For these same sites were calculated the NDVI, in addition to mapping of this ratio, the evaluation of the spatial correlation between this and other studied properties. The clay and phosphorus content showed positive spatial correlation with the NDVI, while no spatial correlation was observed between NDVI and pH. The satellite images from the sensor ETM + Landsat were used to correlate to NDVI to observe the spatial variability of the studied attributes.

  16. Spatial and temporal distribution of litter arthropods in different vegetation covers of Porto Santo Island (Madeira Archipelago, Portugal)

    OpenAIRE

    Antunes, S. C.; Pereira, R.; Sousa, J.P.; Santos, M.C.; Gonçalves, F

    2008-01-01

    The main objective of this study is to assess the soil diversity and temporal and spatial distribution of litter macro-arthropods, captured with pitfall traps, on different vegetation covers from Porto Santo Island (Portugal) with different soil physical and chemical characteristics. The PCA clearly separated sampling areas geographically more exposed to winds and solar radiation, from the others that were not. In this analysis, seasons seemed to have no influence on this distribution. Non-ex...

  17. Oxidative changes during ice storage of rainbow trout (Oncorhynchus mykiss) fed different ratios of marine and vegetable feed ingredients

    DEFF Research Database (Denmark)

    Timm Heinrich, Maike; Eymard, Sylvie; Baron, Caroline P.; Nielsen, Henrik Hauch; Jacobsen, Charlotte

    2013-01-01

    Recently fish meal and oil have increasingly been replaced with proteins and oils from vegetable sources in the diets of farmed salmonids, but the consequences for the oxidative stability of the resulting fish products have not been investigated. The aim of the present study was to evaluate the influence of feeding regime on composition of rainbow trout fillets, as well as on lipid and protein oxidation during storage on ice. Rainbow trout were fed six different diets, which differed in their le...

  18. Feed intake and activity level of two broiler genotypes foraging different types of vegetation in the finishing period

    DEFF Research Database (Denmark)

    Almeida, Gustavo Fonseca; Hinrichsen, Lena Karina; Horsted, Klaus; Thamsborg, Stig Milan; Hermansen, John Erik

    2012-01-01

    A study was performed with 2 broiler genotypes (slow and medium growth) restricted in supplementary feed and foraging 2 different mixed vegetations (grass/clover or chicory) to identify possible benefits of herbage on nutrition during the finishing period (80 to 113 d of age). Three hundred birds were included in a 2 × 2 factorial design with groups of 25 birds replicated 3 times. The use of outdoor areas, performance, and forage intake were investigated. To identify possible differences in fora...

  19. Vegetative compatibility and heterokaryon formation between different isolates of Colletotrichum lindemuthianum by using the nit mutant system

    Scientific Electronic Library Online (English)

    Camila Rodrigues de, Carvalho; Maria Cristina, Mendes-Costa.

    2011-03-01

    Full Text Available Colletotrichum lindemuthianum, the causative agent of bean anthracnose, is one of the most common pathogens leading to expressive damage to plants beyond presenting noticeable variability. The knowledge on vegetative compatibility groups (VCGs) is of particular interest in asexual fungi as they subd [...] ivide the population in groups that can exchange genetic information via heterokaryosis and the parasexual cycle. Among the techniques used in studies about vegetative compatibility groups, the obtainment of nit mutants is apparent. This paper is aimed at obtaining heterokaryons between different isolates of C. lindemuthianum, grouping them in VCGs and evaluating their genetic variability by using the nit mutants system. Nit mutants were obtained from 20 single spore isolates. The mutants were phenotypically classified and paired for complementation and formation of heterokaryons so as to group them in VCGs. Seventeen mutants from the different phenotypic-rates were recovered: nit1, nit2, nit3 and nitM. At the same time, 10 mutants were selected for pairing and division of the anastomosis groups. Nine heterokaryons were obtained and the isolates were divided into 9 vegetative compatibility groups. In the combinations for the formation of anastomosis, 31 compatible combinations and 24 incompatible combinations were observed. It was concluded that the methodology used to select nit mutants in C. lindemuthianum made it possible to determine the vegetative compatibility groups and that such a technique was adequate to prove genetic variability.

  20. Field measurement of soil water repellency and its impact on water flow under different vegetation.

    Czech Academy of Sciences Publication Activity Database

    Lichner, ?.; Hallett, P. D.; Feeney, D. S.; ?ugová, O.; Šír, Miloslav; Tesa?, Miroslav

    2007-01-01

    Ro?. 62, ?. 5 (2007), s. 537-541. ISSN 0006-3088 R&D Projects: GA ?R GA205/05/2312 Institutional research plan: CEZ:AV0Z20600510 Keywords : vegetation * sandy soil * water repellency * hydraulic conductivity Subject RIV: DA - Hydrology ; Limnology Impact factor: 0.207, year: 2007

  1. Spontaneous vegetation succession at different central European mining sites: a comparison across seres.

    Science.gov (United States)

    Prach, Karel; Lencová, Kamila; Rehounková, Klára; Dvo?áková, Helena; Jírová, Alena; Konvalinková, Petra; Mudrák, Ond?ej; Novák, Jan; Trnková, Romana

    2013-11-01

    We performed detrended correspondence analysis (DCA) ordination to compare seven successional seres running in stone quarries, coal mining spoil heaps, sand and gravel pits, and extracted peatlands in the Czech Republic in central Europe. In total, we obtained 1,187 vegetation samples containing 705 species. These represent various successional stages aged from 1 to 100 years. The successional seres studied were more similar in their species composition in the initial stages, in which synathropic species prevailed, than in later successional stages. This vegetation differentiation was determined especially by local moisture conditions. In most cases, succession led to a woodland, which usually established after approximately 20 years. In very dry or wet places, by contrast, where woody species were limited, often highly valuable, open vegetation developed. Except in the peatlands, the total number of species and the number of target species increased during succession. Participation of invasive aliens was mostly unimportant. Spontaneous vegetation succession generally appears to be an ecologically suitable and cheap way of ecosystem restoration of heavily disturbed sites. It should, therefore, be preferred over technical reclamation. PMID:23436061

  2. Different methods for control and comparison of the antioxidant properties of vegetables.

    Czech Academy of Sciences Publication Activity Database

    ?íž, Milan; ?ížová, Hana; Denev, P.; Kratchanova, M.; Slavov, A.; Lojek, Antonín

    2010-01-01

    Ro?. 21, ?. 4 (2010), s. 518-523. ISSN 0956-7135 R&D Projects: GA AV ?R(CZ) 1QS500040507 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702 Keywords : antioxidant activity * polyphenols * vegetables Subject RIV: BO - Biophysics Impact factor: 2.812, year: 2010

  3. Spontaneous vegetation succession at different central European mining sites: a comparison across seres.

    Czech Academy of Sciences Publication Activity Database

    Prach, Karel; Lencová, K.; ?ehounková, Klára; Dvo?áková, K.; Jírová, Alena; Konvalinková, P.; Mudrák, Ond?ej; Novák, J.; Trnková, R.

    2013-01-01

    Ro?. 20, ?. 11 (2013), 7680-7685. ISSN 0944-1344 R&D Projects: GA ?R(CZ) GAP505/11/0256 Institutional support: RVO:67985939 Keywords : succession * vegetation * mining Subject RIV: EH - Ecology, Behaviour Impact factor: 2.757, year: 2013

  4. COMPARISON OF BIODIESEL PRODUCTIVITIES OF DIFFERENT VEGETABLE OILS BY ACIDIC CATALYSIS

    OpenAIRE

    AYTEN SAGIROGLU; ?EBNEM SELEN ISBILIR; HAKKI MEVLUT OZCAN; HATICE PALUZAR; NESLIHAN M. TOPRAKKIRAN

    2011-01-01

    Biodiesel has become a subject which increasingly attracts worldwide attention because of its environmental benefits, biodegradability and renewability. Biodiesel production typically involves the transesterification of a triglyceride feedstock with methanol or other short-chain alcohols. This paper presents a study of transesterification of various vegetable oils, sunflower, safflower, canola, soybean, olive, corn, hazelnut and waste sunflower oils, with the acidic catalyst. Under laboratory...

  5. Knowledge Discovery from Remotely Sensed Vegetation Indices

    Science.gov (United States)

    White, A. B.; Kumar, P.

    2002-12-01

    The objective of this research is to develop KDD (knowledge discovery in databases) techniques for spatio-temporal geo-data, and use these techniques to examine seasonal and inter-annual vegetation health signals. The underlying hypothesis of the research is that the signatures of inter-annual variability of climate on vegetation dynamics as represented by the statistical descriptors of vegetation index variations depend upon a variety of attributes related to the climate, physiography, topography, and hydrology. Several scientific questions related to the identification and characterization of the inter-annual variability ensue as a consequence of this hypothesis. Various vegetation indices will be enlisted to represent vegetation health, such as NDVI (normalized difference vegetation index), EVI (enhanced vegetation index), LAI (leaf area index), FPAR (fraction of photosynthetically active radiation), PSN (photosynthesis), and NPP (net primary product). Relationships between these indices and topography and its derivatives (slope, aspect, etc.), nearness to water bodies, precipitation, temperature, etc. will be analyzed. Preliminary investigations were performed using 13 years of 1 km resolution NDVI data from the AVHRR instrument on NOAA's POES (polar-orbiting operational environmental satellite). Deviations from the 13-year average were utilized in order to identify anomalous behavior. The pilot KDD technique includes distance-based clustering algorithms and Apriori association rule algorithms adapted for spatial-temporal data. Future work will incorporate more complex algorithms such as density-based clustering and constraint-based association mining algorithms.

  6. Evaluation of changes in different climates of Iran, using De Martonne index and Mann–Kendall trend test

    OpenAIRE

    Zareiee, A.R

    2014-01-01

    In this paper, according to the data of 40 stations in Iran during 1967–2005, changes in different climates of Iran evaluated. The De Martonne index and Mann–Kendall trend test are indexes that by uses the precipitation and temperature provide the evaluate possibility of the climate condition and pattern of climate changes. The objective of this study is to evaluation of changes in different climates in Iran. The results of this research showed that, The surface perce...

  7. Soil quality index as affected by different cropping systems in northwestern Himalayas.

    Science.gov (United States)

    Sofi, J A; Bhat, A G; Kirmai, N A; Wani, J A; Lone, Aabid H; Ganie, Mumtaz A; Dar, G I H

    2016-03-01

    Soil quality assessment provides a tool for evaluating the sustainability of soils under different crop cafeterias. Our objective was to develop the soil quality index for evaluating the soil quality indicators under different cropping systems in northwest Himalaya-India. Composite soil samples were taken from the study area from different cropping systems which include T1 (forest soil control), T2 (rice-oilseed, lower belts), T3 (rice-oilseed, higher belts), T4 (rice-oats), T5 (rice-fallow), T6 (maize-oats), T7 (maize-peas), T8 (apple), T9 (apple-beans), and T10 (apple-maize). Physical, chemical, and biological soil indicators were determined, and it was found that soil enzyme activities involved in nutrient cycling were significantly higher in forest soils, which were reflected in higher levels of available pool of nutrients. Carbon stocks were found significantly higher in forest soil which was translated in improved soil physical condition. Principal component analysis (PCA) was performed to reduce multidimensionality of data followed by scoring by homothetic transformation of the selected indicators. Pearson's interclass correlation was performed to avoid redundancy, and highly correlated variables were not retained. Inclusion of legumes in the apple orchard floor recorded highest soil quality rating across the treatments. Cereal-based cropping systems were found in lower soil quality rating; however, the incorporation of peas in the system improved soil health. PMID:26875075

  8. “The Potential Pozzolanic Activity of Different Ceramic Waste Powder as Cement Mortar Component (Strength Activity Index

    Directory of Open Access Journals (Sweden)

    Jay Patel

    2014-03-01

    Full Text Available Under the strong contemporary demand for modern and environmental friendly materials, natural pozzolan can be proved to be such material and several researchers have focused their research efforts in using it as a partial substitute in the manufacture of concrete and mortar. Pozzolans are divided into two categories, namely the natural and the artificial, as metakaoline and silica fume (SF. In recent years, the industry has shifted to using natural pozzolans because of their lower cost and accessibility. A pozzolan is a siliceous material that can be used as an inexpensive Substitute for cement in mortar mixtures. The objective of this experimental study was to examine the possibility of reusing ceramic materials waste from ceramic industry as partial cement replacement in mortar and concrete. The different types of ceramic waste were finely ground to specific sizes (0–45 lm, 45–75 lm and 75–150 lm from different industries and its pozzolanic activity was determined. The compressive strength activity index at 7, 28 days and accelerated curing was determined in mortars produced with each finely grounded waste ceramics and different percentages of partial cement replacement. As per Indian standard mortar bar tests on 70.6*70.6*70.6 mm3 size mortar specimens were performed and results concluded with comparison to nominal mix specimen. own text.

  9. Dietary Intake in Body Mass Index Differences in Community-Based Japanese Patients with Schizophrenia.

    Directory of Open Access Journals (Sweden)

    Haruyuki Ito

    2015-05-01

    Full Text Available Patients with schizophrenia reportedly have a high prevalence of obesity. One of the reasons is a poor choice of diet. The goal of this study was to clarify characteristics of the dietary intake across the strata of the body mass index (BMI and to compare the general population and patients with schizophrenia in Japan.This is a cross-sectional study of 51 patients with schizophrenia residing in rural areas in 2011. Anthropometric indices (of height, weight, body mass index were measured at the commencement of the survey. Intakes of energy, protein, fat, carbohydrate, calcium, phosphorus, vitamins, total fiber, and salt were noted through a 3-day dietary recording. The nutrient intake was estimated using Excel add-in software (Excel Eiyou-kun Ver. 6.0, Kenpakusha Co., Ltd.. Patients were divided into two groups: those with a BMI ?25 kg/m(2 and with a BMI <25 kg/m(2, and the differences in their nutrition intake were analyzed. To compare these patients with the general population, the results of the National Health and Nutrition Survey, 2010 (NHNS were used (the NHNS group. For statistical analysis, an unpaired t-test was performed with P < 0.05.Patients with a BMI ?25 kg/m(2 had the higher intakes than those with a BMI <25 kg/m(2 of energy, fat and phosphorus and salt. Patients with schizophrenia showed higher intakes of energy, carbohydrate, fat, calcium, phosphorus and salt than the NHNS group.The characteristics of the dietary intake in patients with schizophrenia were suggested the food constitution that is likely to increase the body weight.

  10. TERRESTRIAL VEGETATION GREENNESS OF THE LOWER GALVESTON BAY WATERSHED FROM SATELLITE REMOTE SENSING AND ITS RELATION TO WATER AND THE SALINITY REGIME OF THE GALVESTON BAY ESTUARY

    Science.gov (United States)

    Spatial and temporal variability of vegetation greenness have been determined for coastal Texas using biweekly Normalized Difference Vegetation Index (NDVI) data derived from the Advanced Very High Resolution Radiometer (AVHRR). Results are presented on relationships between grou...

  11. A COMPARISON OF THE SALINITY REGIME ALONG THE TEXAS COAST WITH TERRESTRIAL VEGETATION GREENNESS AND WATER USE IN THE GALVESTON BAY WATERSHED USING REMOTING SENSING

    Science.gov (United States)

    Variability in vegetation greenness was determined for the Galveston Bay watershed using biweekly Normalized Difference Vegetation Index (NDVI) data derived from the Advanced Very High Resolution Radiometer (A VHRR) flown on NOAA satellites. NDVI variability was compared with reg...

  12. Organochlorine pesticide residues in different Indian cereals, pulses, spices, vegetables, fruits, milk, butter, Deshi ghee, and edible oils.

    Science.gov (United States)

    Kaphalia, B S; Takroo, R; Mehrotra, S; Nigam, U; Seth, T D

    1990-01-01

    A total of 244 samples of cereals (wheat flour, rice, and maize), pulses (arhar, moong, gram, lentil, and black gram), spices (turmeric, chili, coriander, and black pepper), vegetables (potato, onion, spinach, cabbage, brinjal, and tomato), fruits (mango, guava, apple, and grape), milk, butter, Deshi ghee, and edible oils (vegetable, mustard, groundnut, and sesame) collected from different cities of Northern Province (Utter Pradesh) were analyzed by gas liquid chromatography for the presence of organochlorine pesticide residues. Residues of hexachlorocyclohexane (HCH) and 2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane (DDT) were detected in about 85% of the total samples of cereals, spices, milk, butter, Deshi ghee, and edible oils analyzed in the present study. However, the residue levels were either very small (less than 0.06 ppm) or not detected at all in pulses, vegetables, and fruits as compared with very high concentrations in wheat flour (4.42 and 0.12 ppm), butter (1.19 and 4.85 ppm), mustard oil (1.26 and 2.42 ppm), Deshi ghee (1.10 and 3.84 ppm), vegetable oil (1.02 and 0.59 ppm), groundnut oil (0.51 and 1.49 ppm), and chili (0.48 and 1.92 ppm). The levels of HCH and DDT residues detected in rice, maize, turmeric, corlander, black pepper, and all the vegetables and fruits were also lower than those found in wheat flour, oil, and fat samples analyzed in the present study. These findings suggest that a restricted and controlled use of such persistent pesticides may be useful for decreasing their contamination levels in different food items. PMID:1698760

  13. Vegetational Succession on Different Age Series Sponge Iron Solid Waste Dumps with Respect to Top Soil Application

    Directory of Open Access Journals (Sweden)

    B. Kullu

    2011-01-01

    Full Text Available Vegetation composition of different age series sponge iron solid w aste dumps was analyzed with respect to the impact of top soil application on vegetation succession. Study revealed that freshly laid dump, without top soil cover was devoid of any vegetation. However, 1, 3 and 5 year old dumps were colonized by grasses, sedges, forbs and shrubs. Tree species could be recorded in 3 and 5 year old dumps, but were absent in 1 year old dump. In all the dumps, species belonging to forbs showed the highest percentage contribution to species composition which was followed by grasses. Common occurrence of certain plant species in all the dumps indicated their greater adaptability to the adverse condition of waste material. IVI of herbaceous plants gradually decreased with dump age which was replaced by occupation of shrub and tree species in older dump. Among the families, Poaceae dominated in all the dumps. Species richness and diversity showed increasing trend, where as dominance showed decreasing trend with increasing dump age. Patch with top soil cover always showed highest species richness, follow ed by mixed patch and lowest by the patch only with waste material. The study revealed that top soil acted as seed bank and its application on sponge iron solid waste dump positively contributed towards species richness and vegetation growth.

  14. How do sink and source activities influence the reproduction and vegetative growth of spring ephemeral herbs under different light conditions?

    Science.gov (United States)

    Sunmonu, Ninuola; Kudo, Gaku

    2014-07-01

    Spring ephemeral herbs inhabiting deciduous forests commonly complete reproduction and vegetative growth before canopy closure in early summer. Effects of shading by early canopy closure on reproductive output and vegetative growth, however, may vary depending on the seasonal allocation patterns of photosynthetic products between current reproduction and storage for future growth in each species. To clarify the effects of sink-source balance on seed production and bulb growth in a spring ephemeral herb, Gagea lutea, we performed a bract removal treatment (source reduction) and a floral-bud removal treatment (sink reduction) under canopy and open conditions. Leaf carbon fixations did not differ between the forest and open sites and among treatments. Bract carbon fixations were also similar between sites but tended to decrease when floral buds were removed. Seed production was higher under open condition but decreased by the bract-removal treatment under both light conditions. In contrast, bulb growth was independent of light conditions and the bract-removal treatment but increased greatly by the bud-removal treatment. Therefore, leaves and bracts acted as specialized source organs for vegetative and reproductive functions, respectively, but photosynthetic products by bracts were flexibly used for bulb growth when plants failed to set fruits. Extension of bright period was advantageous for seed production (i.e., source limited) but not for vegetative growth (i.e., sink limited) in this species. PMID:24879401

  15. The effects of different irrigation levels on vegetative growth of young dwarf cherry trees in a sub-humid climate

    International Nuclear Information System (INIS)

    In this study, the effects of different irrigation treatments on evapotranspiration and vegetative growth parameters such as plant height, trunk cross-sectional area, volume of trees and branch cross-sectional area of 'Z-900'/Gisela-5 young dwarf cherry trees were investigated in a sub-humid climate during 2001-2002. Four irrigation treatments (T1, T2, T3 and T4) were applied based on different percentages of Class A Pan evaporation (50%, 75%, 100% and 125%). Seasonal crop evapotranspiration (ETc) values at applied irrigation water levels varied from 327 to 656 mm and from 354 to 733 mm for 2001 and 2002, respectively. While the difference between water levels was 25%, the difference in evapotranspiration for water levels was found to be 21-30%. Maximum average values of vegetative growth parameters area were obtained in T4 treatment in each experimental year. Although the amount of irrigation water for treatments increased, values of vegetative growth parameters didn't indicate a proportional change. (author)

  16. Light sharing among different forest strata for sustainable management of vegetation and regeneration

    OpenAIRE

    Balandier, P.; Marquier, A.; Dumas, Y.; Gaudio, N.; Philippe, G.; Da Silva, D; Adam, B.; Ginisty, C.; Sinoquet, H.

    2009-01-01

    There is a current trend towards managing forests with multiple objectives, in particular to preserve or increase biodiversity and sustainability. There is renewed interest in understorey vegetation as a way both to increase the number of species and, indirectly, to favour fauna, including game, or improve soil quality. However, this stratum of herbaceous or shrubby species can also compete with young tree seedling and jeopardise tree regeneration. Hence a compromise has to be found among the...

  17. Economic Study on Winter Vegetables Produced by Different Categories of Farms

    OpenAIRE

    M.S. Sultana; F. Kabir; Islam, M S; M.M. Rashid; A.I. Akon

    2005-01-01

    The study was designed to assess the comparative profitability of selected winter vegetables like potato, cauliflower and tomato. To achieve this objective, total of 75 farmers, 25 producing potato, 25 producing cauliflower and 25 producing tomato were selected. For this purpose, Cobb-douglas production function model was used. Per hectare total cost of production of potato, cauliflower and tomato were 51396.79, 64406.06 and 61663.87 TK., respectively and the corresponding gross incomes were ...

  18. Age and gender differences in disabling foot pain using different definitions of the manchester foot pain and disability index

    Directory of Open Access Journals (Sweden)

    Taylor Anne W

    2011-10-01

    Full Text Available Abstract Background The Manchester Foot Pain and Disability Index (MFPDI has been used to determine the prevalence of disabling foot pain in several studies, however there is some debate as to which case definition is most appropriate. The objective of this study was to explore age and gender differences in the proportion of people with disabling foot pain using three different case definitions of the MFPDI and for each individual MFPDI item. Methods A random sample of 223 participants aged 27 to 90 years (88 males and 135 females from the North West Adelaide Health Study, who reported having pain, aching or stiffness in either of their feet on most days in the last month, completed the MFPDI by telephone interview. The proportion of people with disabling foot pain was determined using three definitions: (i Definition A-at least one of the 17 items documented on at least some days in the last month; (ii Definition B-at least one of the 17 items documented on most/every day(s in the last month, and; (iii Definition C-at least one of the ten functional limitation items documented on most/every day(s in the last month. Cross-tabulations and chi-squared statistics were used to explore differences in responses to the MFPDI items according to age and gender. Results The proportion of people with disabling foot pain according to each definition was as follows: Definition A (100%, Definition B (95.1% and Definition C (77.6%. Definition C was most sensitive to age and gender differences. Exploration of individual MFPDI items indicated that age significantly affected both the pain intensity and functional limitation items, with younger people more likely to report their foot pain being worse in the morning, and older people more likely to report functional limitations. Although gender did not influence responses to the personal appearance items, women were more likely report functional limitations than men. Conclusions Definition C of the MFPDI is more sensitive to age and gender differences in the proportion of people with disabling foot pain, and would therefore seem to be the most appropriate case definition to use in epidemiological studies involving a broad age range of participants.

  19. Kinetics of soil enzyme activities under different ecosystems: An index of soil quality

    Scientific Electronic Library Online (English)

    Monty, Kujur; Amiya, Kumar Patel.

    2014-03-01

    Full Text Available Soil microbial activity plays an important role in regulating biotransformation, nutrient cycling and hence the microbiological processes are at the center of many ecological functions. The kinetic parameters (Vmax and KmMichaelis constant) of different enzymes (amylase, invertase, protease, urease, [...] and dehydrogenase) were determined in order to assess the metabolic response of soil. The maximum reaction velocity (Vmax) represents a maximum rate of activity when all enzymes are saturated, which markedly increased in forest soil as compared to fresh mine spoil due to the gradual accumulation of soil organic matter. Smaller Km value was estimated in forest soil (FS) as compared to fresh mine spoil (FMS), suggesting the greater affinity of soil enzymes for substrate in FS. The catalytic efficiency (Vmax /Km) reflects an impression on microbial community composition with a change in soil enzymes. These enzyme characters (activities and kinetic parameters) have greater significance as early and sensitive indicators of the changes in soil properties induced by different management systems. These parameters (Vmax and Km) can be useful markers to assess changes in microbial activity of soil, since they represent quantity and affinity of enzymes respectively. The metabolic index (dehydrogenase activity/organic carbon (OC)) was found to be correlated with Vmax of dehydrogenase (r = 0.953; p

  20. The effect of food with different glycaemic index on the blood glucose level

    Directory of Open Access Journals (Sweden)

    Lenka Kou?imská

    2015-08-01

    Full Text Available Blood glucose levels are affected by many factors including the type of foods consumed, processing technology and cooking method. Hormone insulin lowers blood glucose to its constant level, while glucagon, growth hormone, adrenalin and glucocorticoids have the opposite effect. High steepness of the blood glucose level rise after meals may be unfavourable for the organism. Sugars are transferred into the blood at different speeds according to the type of food. Therefore the aim of this study was to confirm experimentally the effect of food on blood glucose levels in men and women of different ages. Two types of low, medium and high-glycaemic index (GI foods were given to 4 men and 4 women of different age (from 35 to 65 years. All volunteers were healthy, slightly overweight, and without any regular sporting activity. None of them had any idea about their daily carbohydrates consumption and what the term glycaemic index meant. The volunteers came to the GI determination fasted in the morning. Their rise in blood glucose level was monitored by glucometer before the meal and after 1 and 2 hours of the consumption of baked potatoes (GI 85, white bread bun (GI 70, boiled potatoes (GI 64, rye bread (GI 62, potato dumplings (GI 52 and white cooked spaghetti (GI 41. Fasting blood sugar levels of volunteers highly depended on their age (p <0.0001 and gender (p <0.0001. The blood glucose values increased with age and were higher in men than in women. Significant influence of food GI on blood glucose levels in both men and women in all the age categories was observed (p <0.0001. An interaction between age and gender was also statistically highly significant (p <0.0001. One hour after consuming food the blood glucose values were significantly different from the values of fasting (p = 0.0035. The differences of these values did not depend on the age (p = 0.0574 and sex (p = 0.8256 of volunteers, but there was a significant difference on the GI value of food (p <0.0001. Significant interactions were also found in case of sex*age (p = 0.0002, age*GI (p <0.0001 and age*sex*GI (p <0.0001. Medium correlation was found between the GI values of food and the rise of blood glucose levels after 1 h (r = 0.6468. After the consumption of high-GI foods the values of glycaemia did not returned to their fasting levels even after 2 hours. There was still significant difference (p = 0.0032, but the values after 2 h were also statistically different from those after 1 hour (p <0.0001. The response to a particular type of consumed food depended on age (p = 0.0018 and especially the GI of foods. Normal 0 21 false false false SK X-NONE X-NONE

  1. Effects of different vegetation zones on CH4 and N2O emissions in coastal wetlands: a model case study.

    Science.gov (United States)

    Liu, Yuhong; Wang, Lixin; Bao, Shumei; Liu, Huamin; Yu, Junbao; Wang, Yu; Shao, Hongbo; Ouyang, Yan; An, Shuqing

    2014-01-01

    The coastal wetland ecosystems are important in the global carbon and nitrogen cycle and global climate change. For higher fragility of coastal wetlands induced by human activities, the roles of coastal wetland ecosystems in CH4 and N2O emissions are becoming more important. This study used a DNDC model to simulate current and future CH4 and N2O emissions of coastal wetlands in four sites along the latitude in China. The simulation results showed that different vegetation zones, including bare beach, Spartina beach, and Phragmites beach, produced different emissions of CH4 and N2O in the same latitude region. Correlation analysis indicated that vegetation types, water level, temperature, and soil organic carbon content are the main factors affecting emissions of CH4 and N2O in coastal wetlands. PMID:24892044

  2. Climate change, growing season water deficit and vegetation activity along the north-south transect of Eastern China from 1982 through 2006

    OpenAIRE

    Sun, P.; Yu, Z.; S. Liu; Wei, X.(Thomas Jefferson National Accelerator Facility, Newport News, VA, 23606, USA); J. Wang(Institute of High Energy Physics, Chinese Academy of Sciences, Beijing); Zegre, N.

    2012-01-01

    Considerable work has been done to examine the relationship between environmental constraints and vegetation activities represented by the remote sensing-based Normalized Difference Vegetation Index (NDVI). However, the relationships along either environmental or vegetation type gradients are rarely examined. The aim of this paper was to identify the vegetation types that are potentially susceptible to climate change through exami...

  3. Factors affecting the wettability of different surface materials with vegetable oil at high temperatures and its relation to cleanability

    DEFF Research Database (Denmark)

    Ashokkumar, Saranya; Adler-Nissen, Jens; Møller, Per

    2012-01-01

    The main aim of the work was to investigate the wettability of different surface materials with vegetable oil (olive oil) over the temperature range of 25–200°C to understand the differences in cleanability of different surfaces exposed to high temperatures in food processes. The different surfac...... contact angle and cleanability. In addition to surface wettability with oil many other factors such as roughness and surface defects play an essential role in determining their cleanability.......The main aim of the work was to investigate the wettability of different surface materials with vegetable oil (olive oil) over the temperature range of 25–200°C to understand the differences in cleanability of different surfaces exposed to high temperatures in food processes. The different surface...... different levels of roughness. The cosine of the contact angle of olive oil on different surface materials rises linearly with increasing temperature. Among the materials analyzed, polymers (PTFE, silicone) gave the lowest cosθ values. Studies of the effect of roughness and surface flaws on wettability...

  4. Description of the difference in plaque index between normal and autistic children age 6-12 years

    Directory of Open Access Journals (Sweden)

    Arinda M Nadya

    2013-07-01

    Full Text Available Background: Oral hygiene status can be seen from the plaque index contained in the mouth. Children aged 6-12 years are school age, they can be taught about oral health care independently. The research objective was to obtain data about description of the differences in plaque index between normal and autistic children aged 6-12 years in Yayasan Autisme Ourdream, Lembaga Pendidikan Autisme Prananda, and SDN Banjarsari in the Bandung city. Materials and Methods: This study was a descriptive analytic. The population was all the students at SDN Banjarsari and autistic children aged 6-12 years in both the foundation. Samplings were collected by simple random sampling, the number of samples obtained normal and autistic children each were 21 persons. Clinical examinations for plaque index using Patient Hygiene Performance (PHP index of Podshadley and Halley. The data were analyzed with independent t-test. Results: The results showed an average of plaque index normal and autistic children aged 6-12 years was 2.06 with a standard deviation of 0.573 and 3.23 with a standard deviation of 0.473. C onclusion: The conclusions showed that there were significant differences in plaque index between normal and autistic children, these values are equally moderate category by Patient Hygiene Performance (PHP index of Podshadley and Halley.

  5. New hyperspectral difference water index for the extraction of urban water bodies by the use of airborne hyperspectral images

    Science.gov (United States)

    Xie, Huan; Luo, Xin; Xu, Xiong; Tong, Xiaohua; Jin, Yanmin; Pan, Haiyan; Zhou, Bingzhong

    2014-01-01

    Extracting surface land-cover types and analyzing changes are among the most common applications of remote sensing. One of the most basic tasks is to identify and map surface water boundaries. Spectral water indexes have been successfully used in the extraction of water bodies in multispectral images. However, directly applying a water index method to hyperspectral images disregards the abundant spectral information and involves difficulty in selecting appropriate spectral bands. It is also a challenge for a spectral water index to distinguish water from shadowed regions. The purpose of this study is therefore to develop an index that is suitable for water extraction by the use of hyperspectral images, and with the capability to mitigate the effects of shadow and low-albedo surfaces, especially in urban areas. Thus, we introduce a new hyperspectral difference water index (HDWI) to improve the water classification accuracy in areas that include shadow over water, shadow over other ground surfaces, and low-albedo ground surfaces. We tested the new method using PHI-2, HyMAP, and ROSIS hyperspectral images of Shanghai, Munich, and Pavia. The performance of the water index was compared with the normalized difference water index (NDWI) and the Mahalanobis distance classifier (MDC). With all three test images, the accuracy of HDWI was significantly higher than that of NDWI and MDC. Therefore, HDWI can be used for extracting water with a high degree of accuracy, especially in urban areas, where shadow caused by high buildings is an important source of classification error.

  6. The role of vegetated areas on fish assemblage of the Paraná River floodplain: effects of different hydrological conditions

    Scientific Electronic Library Online (English)

    Juan José, Neiff; Alicia Poi de, Neiff; Marta B. Canón, Verón.

    2009-03-01

    Full Text Available Neste artigo analisamos as mudanças na composição e abundância das assembléias de peixes de sete áreas úmidas de planície de inundação com vegetação e com diferentes conectividades e em diferentes condições hidrológicas: depois de uma conexão prolongada da planície de inundação com o canal principal [...] , durante o recuo das águas e após um isolamento prolongado. Nós também investigamos o tamanho e abundância das espécies migratórias de grande tamanho encontradas nestas áreas úmidas e os recursos alimentares explorados pelas espécies dominantes. Os peixes foram capturados com rede durante o dia (8.0 m x 1.50 m, malha de 5 mm) nos bancos de macrófitas. Apesar do alto número de espécies registradas (100), a riqueza de espécies nas amostras variou entre 7 e 31, de acordo com o local e data de coleta. A análise de cluster indicou uma baixa similaridade entre os locais tanto durante o período de isolamento como no de conexão prolongada. A substituição de espécies decresceu do período de cheia (? = 40.33) a vazante (? = 33.83), com o valor mínimo de índice de diversidade beta obtido durante o isolamento das áreas úmidas da planície de inundação (? = 26.83). Os resultados indicaram que diferentes populações dominantes de peixes ocorrem em condições hidrológicas diferentes, mesmo quando fases de cheia e de isolamento ocorreram na mesma estação em anos diferentes. A ordenação (NMDS) indicou a importância das condições hidrológicas na estruturação das assembléias de peixes na planície de inundação estudada. Caracídeos de pequeno tamanho, tipicamente associados à macrófitas, dominaram a assembléia de peixes, enquanto que indivíduos jovens de espécies de maior porte e migratórias foram encontradas em baixa abundância. O comprimento padrão máximo dos peixes capturados foi de 28 cm; para espécies migratórias de maior porte o comprimento padrão variou de 1,6 a 25 cm. Os peixes dominantes utilizaram vários recursos alimentares, mas organismos associados às macrófitas litorâneas apresentaram uma alta frequência de ocorrência nas três condições hidrológicas. A alta riqueza de espécies de peixes nos pequenos lagos com vegetação foi relacionado à alta heterogeneidade espacial durante as diferentes condições hidrológicas. Distúrbios nos pulsos hidrológicos podem reduzir a biodiversidade pela modificação da conectividade da área de inundação com o canal principal do rio. A conservação das áreas úmidas com vegetação requer a manutenção da variação de conectividade a fim de proporcionar a diversidade de habitats ao longo do tempo. Abstract in english In this paper, we analyze the changes in composition and abundance of fish assemblages in seven vegetated floodplain wetlands with different connectivity across different hydrologic conditions: after a prolonged connection of the floodplain with the main channel, during receding water, and after a p [...] rolonged isolation. We also investigated the size and abundance of large-sized migratory species found in these wetlands and the food resources exploited by the dominant fish. Fishes were captured by diurnal seining (8.0 m x 1.50 m, 5 mm mesh) along macrophyte banks. Despite the high total number of species registered (100), sample species richness varied between 7 and 31, depending on the sampling site and the sampling date. Cluster analysis indicated low similarity between sites during both the isolation and the prolonged connection. Species turnover decreased from high water (? = 40.33) to low water (? = 33.83), with the minimum value of beta diversity index obtained during the isolation of the floodplain wetlands (? = 26.83). Our results indicated that different dominant populations of fish occur in different hydrological conditions, even though high water and isolation phases occur in the same season of different years. The ordination (NMDS) indicated the importance of hydrologic conditions in structuring fish assemblages in the studied floodplain. Small

  7. Transfer of radiocesium to four cruciferous vegetables as influenced by organic amendment under different field conditions in Fukushima Prefecture

    International Nuclear Information System (INIS)

    Soil-to-plant transfer of radiocesium (137Cs) in four cruciferous vegetables as influenced by cattle manure-based compost amendment was investigated. Komatsuna, mustard, radish and turnip were cultivated in three different 137Cs-contaminated fields at Nihonmatsu City in Fukushima Prefecture from June to August 2012. Results revealed that organic compost amendments stimulated plant biomass production and tended to induce higher 137Cs concentration in the cruciferous vegetables in most cases. Among the studied sites, Takanishi soil possessing low exchangeable potassium (0.10 cmolc kg?1) was associated with an increased concentration of 137Cs in plants. Radiocesium transfer factor (TF) values of the vegetables ranged from 0.025 to 0.119. The increase in 137Cs TFs was dependent on larger plant biomass production, high organic matter content, and high sand content in the studied soils. Average 137Cs TF values for all study sites and compost treatments were higher in Komatsuna (0.072) and radish (0.059), which exhibited a higher biomass production compared to mustard and turnip. The transferability of 137Cs to vegetables from soils was in the order Komatsuna > radish > mustard > turnip. The highest 137Cs TF value (0.071) of all vegetables was recorded for a field where the soil had high organic matter content and a high clay proportion of 470 g kg?1 consisting of Al-vermiculite clay mineral. - Highlights: • Komatsuna and radish possessing higher biomass resulted in higher 137Cs TF than mustard and turnip. • Soil with low exchangeable K (0.10 cmolc kg?1) increased 137Cs concentration in plants. • Compost amendments tended to induce higher 137Cs transfer from soil to plants than the control. • Soil with Al-vermiculite mineral and high organic matter resulted in higher 137Cs transfer

  8. [Ecological stoichiometric characteristics in leaf and litter under different vegetation types of Zhifanggou watershed on the Loess Plateau, China].

    Science.gov (United States)

    Li, Xin; Zeng, Ouan-chao; An, Shao-Shan; Dong, Yang-Hong; Li, Ya-Yun

    2015-03-01

    The purpose was to characterize the effects of vegetation types on plant leaf and litter carbon (C), nitrogen (N), phosphorus (P), potassium (K) and C: N: P: K ecological stoichiometric characteristics in seven dominant plant species, including Robinia pseudoacacia, Syringa, Sophora viciifolia, Hippophae rhamnoides, Rosa xanthina, Artemisia sacrorum, Artemisia giraldii, of Zhifanggou Watershed on the Loess Plateau, China. This paper indicated the differences between the contents of C, N, P and K and the characteristics of ecological stoichiometric in the different vegetation types, including forest type, shrub type and grass type. Concentrations of C, N, P and K were measured, and C: N: P: K was estimated for different vegetation types. There were no significant differences in leaf C, N and P concentrations among the three vegetation types. But significant differences in leaf K concentration existed, and the K concentration in leaf was the highest in grass type, and the lowest in shrub type. The contents of C, N, P and K in leaf were much higher than those in litter, especially in shrub and grass types. The resorption efficiencies of C, N, P and K were different, and their ranges varied 6.16%-22.84%, 24.38%-65.18%, 22.38%-77.16% and 60.99%- 89.35%, respectively. Grass type had the highest C, P and K resorption efficiencies, and the lowest N resorption efficiency. Values of the N: P ratio in leaf varied in the range of 12.14-19.17, and varied in the range of 12.84-30.67 in litter. Values of the N: P ratio in leaf were the highest in shrub type (19. 17), and the lowest in grass (12. 14), indicating that the growth of shrub plants was limited by P, while the growth of grass plants was limited by N. The K concentration in leaf was significantly negatively correlated with values of the N: P ratio in leaf, and the K concentration in litter was significantly negatively correlated with values of the C: P ratio in leaf. Findings in this study highlighted the characteristics of accumulation and and return of leaf and litters nutrients during the different vegetation succession on the Loess Plateau. PMID:25929080

  9. Vegetation succession and soil infiltration characteristics under different aged refuse dumps at the Heidaigou opencast coal mine

    Directory of Open Access Journals (Sweden)

    Huang Lei

    2015-07-01

    Full Text Available Vegetation succession and soil infiltration characteristics under five different restoration models of refuse dumps including different-aged revegetated sites (1995, 1998, 2003 and 2005 in the northern, eastern and western open-pit coal mine dump and a reference site with native vegetation, which had never been damaged by coal mining activities on the Heidaigou Open Cut Coal Mine were studied. Changes in the plant species, soil properties and infiltration rates were evaluated at the different refuse dumps. The results indicated that the number of herbaceous species, plant cover, biomass, fine particles, and total N, P and SOM increased significantly with increasing site age. However, the number of shrub species decreased since revegetation, its cover increased from 17% to 41% initially and subsequently decreased to the present level of 4%. The natural vegetation community and the northern refuse dump had the highest cumulative infiltration rates of 3.96 and 2.89 cm s−1 in contrast to the eastern and western refuse dumps and the abandoned land, where the highest cumulative infiltration rates were 1.26, 1.04 and 0.88 cm s−1, respectively. A multiple linear regression analysis indicated that the infiltration rate was primarily determined by the silt percentage, SOM, plant coverage and the variation in soil bulk density. Our results provide new ideas regarding future soil erosion controls and sustainable development at open-pit coal mine refuse dumps.

  10. Estimation of Heavy Metal in Vegetables from Different Market Sites of Tribal Based Ranchi City through Icp-Oes and to Assess Health Risk

    Directory of Open Access Journals (Sweden)

    Ratna Ghosh

    2013-12-01

    Full Text Available Inductively Coupled Plasma - Optical Emission Spectrometry (ICP-OES was used to estimate and evaluate the levels of heavy metals in vegetables collected from various sites of Ranchi city (tribal dominated population followed by health risk assessment by determining Metal Pollution Index (MPI, Daily intake of metal (DIM and Health Risk Index (HRI. The concentration levels of Pb, Cd and Ni in vegetables were found to contain beyond than the permissible PFA limit. All sites showed quite a few higher concentrations of Lead (Pb, than the permissible PFA limit. Among thirteen vegetables, Beet, Cucumber, Pea, Beans, Lady’s finger, Corriender leaves and Tomato showed high levels of Pb in vegetables collected from all sites. Health Risk Index was also found > 1 for Cd, Co and Pb. Health Risk Index for Cadmium was 1.64 and 2.38 in Cucumber from Site-6 and Site-8 respectively. In Spinach it was 2.19 and 2.15 respectively for Site-6 and Site-8. Health Risk Index for Pb was > 1 in Cucumber (All sites; 3.54 in Site-8, Pea (All sites except Site-10; 2.45 in Site-7, Beans (All sites; 1.38 in Site-9, Lady’s finger (All sites; 2.03 in Site-7, and Tomato (All sites except Site-10; 2.79 in Site-8. Lead and cadmium were among the most abundant heavy metals in the selected vegetables. The excessive content of these heavy metals in food may causes number of diseases. HRI more than 1 is considered to be not safe for human health. In present study, HRI indicates considerable risk and negative impact on human health.

  11. Optimising view angles for the estimation of leaf area index via entropy-difference analysis

    Indian Academy of Sciences (India)

    Yanjuan Yao; Qiang Liu; Qinhuo Liu; Yanhua Gao

    2012-06-01

    It is important to evaluate the information content of remote sensing data in order to synthetically use multi-source remote sensing data to improve the accuracy and consistency of land surface parameter retrieval. This paper presents a technique for information content evaluation of multi-spectral/angular remote sensing data for the leaf area index (LAI) inversion, the method of entropy-difference analysis.The proposed method is based on a numerical evaluation of the entropy of the observed dataset to learn how much variation in observation is caused by the variation in LAI. The relationship between remote sensing information and the LAI inversion accuracy is validated based on the model-simulated canopy reflectance data and the experiment data. We make the following observation: the larger the entropydifference for canopy reflectance data, the higher the LAI inversion accuracy. That is, choosing a good combination of observation angles is sometimes more important than simply increasing the number of observations. The presented technique may be useful in designing and evaluating quantitative remote sensing algorithms and products.

  12. Effects of different dietary cation-anion balance and cellulase on blood biochemical indexes in sheep

    International Nuclear Information System (INIS)

    Five sheep with average live weight of 38 kg were selected and fitted with permanent ruminal fistulae for the study of the influence of DCAB and cellulase on blood biochemical indexes in sheep. With the design of 5 x 5 Latin square, the goats were undergone four groups of treatments. As sheep in control group were only fed with basic feed, other treatments were fed with basic feed and additives. Those additives were: treatment 1 with cellulase (0.2% of dietary), treatment 2 with DCAB1 (20 mEq/100g DM), treatment 3 with cellulase (0.2% of dietary) and DCAB1 (20 mEq/100g DM) and treatment 4 with cellulase (0.2% of dietary) and DCAB2 (40 mEq/100 g DM). The results show that different DCAB and cellulase had no apparent influence on the concentrations of T3 and T4 (P>0.05), but they had significant influence on the concentration of insulin (P0.05). The study indicated that addition of 0.2% cellulase to dietary while adjusting DCAB to 0.2-40 mEq/100 g DM respectively did not destroy tissues and organs of sheep. (authors)

  13. Improving spatial representation of soil moisture by integration of microwave observations and the temperature-vegetation-drought index derived from MODIS products

    Science.gov (United States)

    Wang, Jun; Ling, Ziwei; Wang, Yang; Zeng, Hui

    2016-03-01

    The microwave observations of land surface soil moisture have been widely used for studying environmental change at large spatial scales. However, the coarse spatial resolution of the products limits their local-scale applications. In this paper, we developed a new method, which integrates the coarse spatial resolution soil moisture derived from microwave sensors and the temperature-vegetation-drought-index (TVDI) derived from the Moderate-resolution Imaging Spectroradiometer (MODIS) products, to spatially downscale soil moisture data from 25-km resolution to 1-km resolution. First, we assessed the quality of the remotely sensed soil moisture by comparing their values with field measured soil moisture at three temporal scales and two spatial scales. Second, we analyzed the robustness of the developed approach namely the PKU method by comparing its performance with the results of three published methods (i.e., the triangle-based method, the Merlin method, and the UCLA method) at the Magqu soil moisture monitoring network located in the northeastern Tibetan grasslands. The modeling results showed that by integrating the contextual information from the relatively fine spatial resolution MODIS products, spatial soil moisture representations were significantly improved. The PKU method produced the most accurate spatially disaggregated soil moisture among the four methods. In conclusion, the PKU method developed in this study is a practical and efficient approach for improving spatial representations of the coarse spatial resolution soil moisture data derived from microwave remote sensors. Within the PKU method, our refined method for estimating the parameters of the dry-edge outperforms the traditional method.

  14. Global changes in dryland vegetation dynamics (1988–2008) assessed by satellite remote sensing: combining a new passive microwave vegetation density record with reflective greenness data

    OpenAIRE

    Andela, N.; Liu, Y.Y.; van Dijk, A.I.J.M.; de Jeu, R. A. M.; McVicar, T.R.

    2013-01-01

    Drylands, covering nearly 30% of the global land surface, are characterized by high climate variability and sensitivity to land management. Here, two satellite observed vegetation products were used to study the long-term (1988–2008) vegetation changes of global drylands: the widely used reflective-based Normalized Difference Vegetation Index (NDVI) and the recently developed passive-microwave-based Vegetation Optical Depth (VOD). The NDVI is sensitive to the chlorophyll concentrations in the...

  15. Analysis of Vegetative on Six Different Landfill Cover Profiles in an Arid Environment.

    Energy Technology Data Exchange (ETDEWEB)

    Dwyer, Stephen F.; McClellan, Yvonne; Reavis, Bruce A.; Dwyer, Brian P.; Newman, Gretchen; Wolters, Gale

    2005-05-01

    A large-scale field demonstration comparing final landfill cover designs was constructed and monitored at Sandia National Laboratories in Albuquerque, New Mexico. Two conventional designs (a RCRA Subtitle 'D' Soil Cover and a RCRA Subtitle 'C' Compacted Clay Cover) were constructed side-by-side with four alternative cover test plots designed for arid environments. The demonstration was intended to evaluate the various cover designs based on their respective water balance performance, ease and reliability of construction, and cost. A portion of this project involves the characterization of vegetation establishment and growth on the landfill covers. The various prototype landfill covers were expected to have varying flux rates (Dwyer et al 2000). The landfill covers were further expected to influence vegetation establishment and growth, which may impact site erosion potential and long-term site integrity. Objectives of this phase were to quantify the types of plants occupying each site, the percentage of ground covered by these plants, the density (number of plants per unit area) of plants, and the plant biomass production. The results of this vegetation analysis are presented in this report.3 DRAFT07/06/14AcknowledgementsWe would like to thank all technical and support staff from Sandia and the USDA Forest Service's Rocky Mountain Station not included in the authors' list of this document for their valuable contributions to this research. We would also like to acknowledge the Department of Energy's Subsurface Contaminants Focus Area for funding this work.4

  16. Differences in sedge fen vegetation upstream and downstream from a managed impoundment

    Science.gov (United States)

    Kowalski, Kurt P.; Wilcox, Douglas A.

    2003-01-01

    The U.S. Fish and Wildlife Service proposed the restoration of wetlands impacted by a series of drainage ditches and pools located in an extensive undeveloped peatland in the Seney National Wildlife Refuge, Michigan. This study examined the nature and extent of degradation to the Marsh Creek wetlands caused by alteration of natural hydrology by a water-storage pool (C-3 Pool) that intersects the Marsh Creek channel. We tested the hypothesis that a reduction in moderate-intensity disturbance associated with natural water-level fluctuations below the C-3 dike contributed to lower species richness, reduced floristic quality and a larger tree and shrub component than vegetation upstream from the pool. Wetland plant communities were sampled quantitatively and analyzed for species richness, floristic quality and physiognomy. Aerial photographs, GIS databases and GPS data contributed to the characterization and analysis of the Marsh Creek wetlands. Results showed that there was lower species richness in vegetated areas downstream from the pool, but not the anticipated growth in shrubs. Wetland vegetation upstream and downstream from the pool had similar floristic quality, except for a greater number of weedy taxa above the pool. Seepage through the pool dike and localized ground-water discharge created conditions very similar to those observed around beaver dams in Marsh Creek. In essence, the dike containing the C-3 Pool affected hydrology and wetland plant communities in a manner similar to an enormous beaver dam, except that it did not allow seasonal flooding episodes to occur. Management actions to release water from the pool into the original Marsh Creek channel at certain times and in certain amounts that mimic the natural flow regime would be expected to promote greater plant species richness and minimize the negative impacts of the dike.

  17. Evaluation of Eucalyptus clones in different places seeking to the production of vegetal charcoal Avaliação de clones de Eucalyptus em diferentes locais visando à produção de carvão vegetal

    Directory of Open Access Journals (Sweden)

    Thiago Andrade Neves

    2011-12-01

    Full Text Available

    This research aim to evaluate the wood and charcoal quality of three Eucalyptus clones planted at different places and to verify the existent functional relations between the basic density and the depth of penetration of the Pilodyn pin. Three Eucalyptus clones were evaluated and four trees were sample for each clone and place. It was determined the depth of penetration of a Pilodyn pin at 1.30 m of height of the soil (DBH, average basic density (DBm, the basic density at DBH, the calorific value, lignin, total extractive, ashes and holocellulose contents and elemental chemical analysis (C, H, N and O. The wood was carbonized and the charcoal produced was evaluated quantitatively and qualitatively. In the evaluation of the wood characteristics a completely randomized design disposed in a factorial scheme 3 x 2 was used. A linear model was adjusted between DBm and the depth of penetration of the Pilodyn pin. It was possible to conclude that the clones present potential to be used for energy. The charcoal produced may be used in siderurgy. The linear model adjusted between DBm and the penetration of the Pilodyn pin was satisfactory.

    doi: 10.4336/2011.pfb.31.68.319

    Os objetivos desse trabalho foram avaliar a qualidade da madeira e do carvão vegetal de três clones de Eucalyptus plantados em diferentes locais e verificar a relação funcional existente entre a densidade básica e a profundidade de penetração do pino do Pilodyn. Foram avaliados três clones de Eucalyptus e amostradas quatro árvores por clone em cada local. Determinou-se a profundidade de penetração de um pino de aço do Pilodyn a 1,30 m de altura do solo (DAP, a densidade básica média (DBm, a densidade básica no DAP, o poder calorífico superior e os teores de lignina, extrativos totais, cinzas, holocelulose e a análise química elementar (C, H, N e O. A madeira foi carbonizada e o carvão produzido foi avaliado quantitativamente e qualitativamente. Na avaliação das características da madeira, utilizou-se um DIC em um esquema fatorial 3 x 2. Foi ajustado um modelo linear entre a DBm e a profundidade de penetração do pino do Pilodyn. Foi possível concluir que os clones apresentaram potencial para o uso energético. O carvão vegetal produzido pode ser utilizado na siderurgia. O modelo linear ajustado entre a DBm e a penetração do pino do Pilodyn mostrou-se satisfatório.

    doi: 10.4336/2011.pfb.31.68.319

  18. Análise espacial de atributos do solo e cobertura vegetal em diferentes condições de pastagem / Spatial analysis of soil attributes and cover vegetation under different grazing conditions

    Scientific Electronic Library Online (English)

    Durval N., Neves Neto; Antonio C. dos, Santos; Perlon M., Santos; Jonahtan C., Melo; Josemara S., Santos.

    2013-09-01

    Full Text Available As áreas destinadas à pecuária têm-se expandido sobre áreas de vegetação nativa promovendo transformações na qualidade do solo. O objetivo foi avaliar os atributos de um Neossolo Quartzarênico sob diferentes coberturas vegetais para saber se a degradação do pasto representa a degradação do solo. As [...] áreas avaliadas foram: floresta nativa; capoeira; pastagem sem controle de lotação animal; pastagem em pousio; pastagem com invasoras; pastagem degradada com solo descoberto e invasoras, pastagem degradada com invasoras e espécies arbóreas e pastagem com baixa produção de forragem. Todas as pastagens eram formadas pela gramínea Brachiaria brizantha cv. Marandu. Realizaram-se 128 amostras de solo nas profundidades de 0-5 e 5-10 cm, dentro de cada área de manejo considerada como parcela experimental e a cobertura do solo foi quantificada. Foram mensuradas propriedades químicas e físicas do solo. Os dados foram submetidos a estudo geoestatístico. Foram constatados aumento na resistência mecânica à penetração e diminuição nos teores de matéria orgânica nas áreas mais degradadas. Pasto degradado não representa necessariamente solo degradado enquanto solo degradado está relacionado a pastagem degrada. Abstract in english The areas for livestock raising have expanded into areas of native vegetation, promoting changes in soil quality. The objective of this study was to evaluate the attributes of a Entisol under different vegetation covers to whether the pasture degradation represents soil degradation. The areas evalua [...] ted were: native forest, shrub, uncontrolled grazing animal stocking, grazing in fallow pasture with weeds; degraded pasture with bare soil and weeds, degraded pasture with weeds and tree species and grassland with low forage production. All pastures were formed by Brachiaria brizantha cv. Marandu. Hundred and twenty eight soil samples were collected in 0-5 and 5-10 cm, within each management area, considered as an experimental plot and soil cover was quantified. The chemical and physical properties of the soil were measured. Data were subjected to geoestatistical study. Increase in penetration resistance and decrease in the levels of organic matter were observed in the most degraded areas. Degraded pasture is not necessarily degraded land while degraded soil is related to grazing degrades.

  19. Refinement of microwave vegetation indices

    Science.gov (United States)

    Previous investigations have established the basis for a new type of vegetation index based on passive microwave satellite observations. These microwave vegetation indices (MVIs) have been qualitatively evaluated by examining global spatial and seasonal temporal features. Limited quantitative studie...

  20. Carbon mineralization of flooded boreal soil and vegetation under different temperature and oxygen conditions

    Science.gov (United States)

    Kim, Y.; Ullah, S.; Roulet, N.; Moore, T.

    2009-05-01

    Flooding of terrestrial ecosystems significantly alters carbon (C) mineralization rates, which results in increasing emissions of carbon dioxide (CO2) and methane (CH4). To better understand the changes after water impoundment, C mineralization under flooded conditions needs to be investigated. This study investigates CO2 and CH4 fluxes from flooded boreal soil and vegetation, compares them to the fluxes of non- flooded treatment, and examines how environmental factors affect the fluxes. We conducted short-term in vitro experiments using boreal forest soil (FH layer), peat soil (0 to 5 and 5 to 15 cm) layer, and black spruce needles and small twigs, and shrub, sedge, lichen, and moss tissues. Flooded samples were incubated in 1- L Mason jars without light, under three temperatures (5, 12, and 24degC) and 0 and 50 percent of ambient oxygen (O2) concentration, and non-flooded ones were incubated in 1-L plastic containers under same light and temperature conditions to those of flooded samples and ambient oxygen concentration. We collected gas samples after flushing with nitrogen gas and air, and the fluxes of CO2 and CH4 were determined by gas chromatography. The average CO2 and CH4 fluxes in all materials were 200 and 0.8 microgram C/g organic matter/day, with smaller CO2 fluxes and larger CH4 fluxes than the fluxes of non-flooding (CO2 and CH4: 370 and 0.2 microgram C/g organic matter/day). Among the flooded samples, forest and peatland ground vegetation showed much high CO2 fluxes, and peat soils released more CH4 than other materials. Higher temperatures increased emissions of both CO2 and CH4, and the lower O2 concentration increased CH4 emissions. These results suggest the flooded vegetation and peat soil largely contribute to the total C emission in the flooded ecosystem and that spatial and temporal variability in CO2 and CH4 emissions can be related to substrate type, temperature and O2 concentration.

  1. Comparing Different Approaches for Mapping Urban Vegetation Cover from Landsat ETM+ Data: A Case Study on Brussels

    Directory of Open Access Journals (Sweden)

    Frank Canters

    2008-06-01

    Full Text Available Urban growth and its related environmental problems call for sustainable urban management policies to safeguard the quality of urban environments. Vegetation plays an important part in this as it provides ecological, social, health and economic benefits to a city’s inhabitants. Remotely sensed data are of great value to monitor urban green and despite the clear advantages of contemporary high resolution images, the benefits of medium resolution data should not be discarded. The objective of this research was to estimate fractional vegetation cover from a Landsat ETM+ image with sub-pixel classification, and to compare accuracies obtained with multiple stepwise regression analysis, linear spectral unmixing and multi-layer perceptrons (MLP at the level of meaningful urban spatial entities. Despite the small, but nevertheless statistically significant differences at pixel level between the alternative approaches, the spatial pattern of vegetation cover and estimation errors is clearly distinctive at neighbourhood level. At this spatially aggregated level, a simple regression model appears to attain sufficient accuracy. For mapping at a spatially more detailed level, the MLP seems to be the most appropriate choice. Brightness normalisation only appeared to affect the linear models, especially the linear spectral unmixing.

  2. The Abundance of Pioneer Vegetation and Their Interaction with Endomycorrhiza at Different Land Qualities after Merapi Eruption

    Directory of Open Access Journals (Sweden)

    Cahyono Agus

    2012-12-01

    Full Text Available Eruption of Merapi volcano caused accumulation of lahar materials that led to extensive land degradation.  This research was to study the population of pioneer plants and their correlation with endomycorrhiza population at  different land qualities after Merapi eruption.  Samples of soil, pioneer plants, and endomycorrhiza were collected from Merapi volcano, 1 year after eruption, using stratified sampling method based on plant densities, with the following categories: dense vegetation, moderately dense vegetation, sparse vegetation, and control (bare land, with 3 replications for each category.  Pioneer plants and endomycorrhiza were identified. Plant biomass, soil pH, total-C,-N, and exchangeable-K, -Ca, -Mg, -Fe were analyzed. The abundance of pioneer plants and their interaction with mycorrhiza was strongly correlated with depth of eruption material, quantity of sandy texture, soil pH, total-C and total-N, exchangeable-K, exchangeable-Ca, exchangeable-Mg, and exchangeable-Fe.  Among the 12 identified pioneer plants, only Acacia villosa, Fiurena ciliaris, and Bidens pilosa were recommended as plant-remediator to improve soil chemical, physical and biological properties. Among the 3 genera of endomycorrhiza (Acaulospora, Gigaspora, Glomus, only Acaulospora was recommended to be a biological agent to rehabilitate sandy soil area.  This research indicated that adaptive pioneer plants and endomycorrhiza  were likely to be suitable for biological agents to stimulate recovery of degraded land through improvement of physical, chemical, and biological properties, that will stimulate plant growth and biodiversity.Keywords: eruption of Merapi, endomycorrhiza, land quality, pioneer plant

  3. Fourier Transform Infrared Spectroscopy (FTIR and Multivariate Analysis for Identification of Different Vegetable Oils Used in Biodiesel Production

    Directory of Open Access Journals (Sweden)

    Rosana de Cássia de Souza Schneider

    2013-03-01

    Full Text Available The main objective of this study was to use infrared spectroscopy to identify vegetable oils used as raw material for biodiesel production and apply multivariate analysis to the data. Six different vegetable oil sources—canola, cotton, corn, palm, sunflower and soybeans—were used to produce biodiesel batches. The spectra were acquired by Fourier transform infrared spectroscopy using a universal attenuated total reflectance sensor (FTIR-UATR. For the multivariate analysis principal component analysis (PCA, hierarchical cluster analysis (HCA, interval principal component analysis (iPCA and soft independent modeling of class analogy (SIMCA were used. The results indicate that is possible to develop a methodology to identify vegetable oils used as raw material in the production of biodiesel by FTIR-UATR applying multivariate analysis. It was also observed that the iPCA found the best spectral range for separation of biodiesel batches using FTIR-UATR data, and with this result, the SIMCA method classified 100% of the soybean biodiesel samples.

  4. Vegetative and reproductive development of different avocado selections Co60 irradiated

    International Nuclear Information System (INIS)

    Data of vegetative and reproductive behavior were registered of 2 cultivars and 5 selections avocado trees which survived 2.0 krad irradiation dosage these trees are in their third year of development. Decreases in graft height were found this decrease were more evident in selections C 137 PLS and C 39 PMe (10 and 15%, respectively), and in cultivar Colin V-33 (40%) irradiated trees of the same selections presented and increase of 100% in flower density and fruit set. Selection Colin V-101 and cv. Fuerte did not present flowering so neither fruit set. We also detected a modification in fructification normal habit of selections Colinmex and C 175 PLS since fruit arises from main stem. (Author)

  5. Promoting Fruit and Vegetable Intake through Messages Tailored to Individual Differences in Regulatory Focus

    Science.gov (United States)

    Latimer, Amy E.; Williams-Piehota, Pamela; Katulak, Nicole A.; Cox, Ashley; Mowad, Linda; Higgins, E. Tory; Salovey, Peter

    2009-01-01

    Background Researchers must identify strategies to optimize the persuasiveness of messages used in public education campaigns encouraging fruit and vegetable (FV) intake. Purpose This study examined whether tailoring messages to individuals' regulatory focus (RF), the tendency to be motivated by promotion versus prevention goals, increased the persuasiveness of messages encouraging greater FV intake. Method Participants (n=518) completed an assessment of their RF and were randomly assigned to receive either prevention- or promotion-oriented messages. Messages were mailed 1 week, 2 months, and 3 months after the baseline interview. Follow-up assessments were conducted 1 and 4 months after the baseline assessment. Results Regression analyses revealed that at Month 4, the messages were somewhat more efficacious when congruent with participants' RF. Conclusion RF may be a promising target for developing tailored messages promoting increased FV intake, and particularly for encouraging individuals to meet FV guidelines. PMID:18670833

  6. Organic Matter Fractions and Quality of the Surface Layer of a Constructed and Vegetated Soil After Coal Mining. II - Physical Compartments and Carbon Management Index

    Directory of Open Access Journals (Sweden)

    Otávio dos Anjos Leal

    2015-06-01

    Full Text Available Soils constructed after mining often have low carbon (C stocks and low quality of organic matter (OM. Cover crops are decisive for the recovery process of these stocks, improving the quality of constructed soils. Therefore, the goal of this study was to evaluate the effect of cover crops on total organic C (TOC stocks, C distribution in physical fractions of OM and the C management index (CMI of a soil constructed after coal mining. The experiment was initiated in 2003 with six treatments: Hemarthria altissima (T1, Paspalum notatum (T2, Cynodon dactylon (T3, Urochloa brizantha (T4, bare constructed soil (T5, and natural soil (T6. Soil samples were collected in 2009 from the 0.00-0.03 m layer, and the TOC and C stocks in the physical particle size fractions (carbon in the coarse fraction - CCF, and mineral-associated carbon - MAC and density fractions (free light fraction - FLF; occluded light fraction - OLF, and heavy fraction - HF of OM were determined. The CMI components: carbon pool index (CPI, lability (L and lability index (LI were estimated by both fractionation methods. No differences were observed between TOC, CCF and MAC stocks. The lowest C stocks in FLF and OLF fractions were presented by T2, 0.86 and 0.61 Mg ha-1, respectively. The values of TOC stock, C stock in physical fractions and CMI were intermediate, greater than T5 and lower than T6 in all treatments, indicating the partial recovery of soil quality. As a result of the better adaptation of the species Hemarthria and Brizantha, resulting in greater accumulation of labile organic material, the CPI, L, LI and CMI values were higher in these treatments, suggesting a greater potential of these species for recovery of constructed soils.

  7. Egg Weight, Shape Index and Hatching Weight and Interrelationships among These Traits in Native Turkish Geese with Different Coloured Feathers

    OpenAIRE

    SAATC?, Mustafa; KIRMIZIBAYRAK, Turgut; AKSOY, Ali R?za; T?LK?, Muammer

    2005-01-01

    Egg weight, shape index and hatching weight and interrelationship among these three traits have been studied in native Turkish geese with different coloured feathers (black, white, piebald and yellow). Means of the four feather colours for egg weights were 147, 150.49, 142.95, 150.88 g, for shape index 67.01, 66.19, 66.68, 67.12% and for hatching weight 94.99, 98.41, 92.95, 97.40 g, respectively. Egg weight and hatching weight showed significant differences according to feather colour (P <...

  8. Desempenho reprodutivo de coelhas alimentadas com ração contendo diferentes fontes de óleo vegetal = Reproductive performance of rabbit does fed with rations containing different sources of vegetable oil

    Directory of Open Access Journals (Sweden)

    Márcia Aparecida Andreazzi

    2006-07-01

    Full Text Available Foram avaliadas 120 matrizes de coelhas durante dois ciclos reprodutivos. Os animais foram distribuídos em um delineamento experimental inteiramente casualizado, com 4 tratamentos (ração sem óleo e ração com 3% de óleo de canola, de óleo de milho ou de óleo de soja e 30 repetições. Foram coletados os dados de peso vivo das coelhas em cada cobrição, no parto, aos 21 e aos 35 dias de lactação e de consumo durante a gestação, os primeiros 21 dias de lactação e durante o período total de lactação (35 dias. Também foram obtidos os dados referentes ao peso vivo e ao número de láparos ao nascimento, aos 21 e aos 35 dias. Não foram observadas diferenças (P>0,05 entre os tratamentos quanto aos parâmetros de desempenho das coelhas no primeiro ciclo reprodutivo. No entanto os dados referentes ao segundo ciclo demonstraram maior peso vivo (P0,05 pela utilização das rações.One hundred and twenty rabbit does, were evaluated during two productive cycles. The animals were distributed in a completely randomized experimental design, with four treatments (oil-free rations and 3% canola oil, corn oil or soybean oil rations and 30 replications. While data of live weight of rabbit does were collected in each breeding, on birth, on the 21st and the 35th days of lactation, those on feed intake were recorded during gestation, onthe first 21 days of lactation and during the total period of lactation (35 days. Data on the litters live weight and number on birth, on the 21st and the 35th days, were also obtained. There were no differences (p>0.05 among treatments with regard to performance parameters of rabbit does on the first reproductive cycle. However, data concerning the second cycle demonstrated a better live weight (p0.05 by rations containing different sources of vegetable oil fed during the two reproductive cycles.

  9. Sensitivity of fire weather index to different reanalysis products in the Iberian Peninsula

    Directory of Open Access Journals (Sweden)

    J. Bedia

    2012-03-01

    Full Text Available Wildfires are a major concern on the Iberian Peninsula, and the establishment of effective prevention and early warning systems are crucial to reduce impacts and losses. Fire weather indices are daily indicators of fire danger based upon meteorological information. However, their application in many studies is conditioned to the availability of sufficiently large climatological time series over extensive geographical areas and of sufficient quality. Furthermore, wind and relative humidity, important for the calculation of fire spread and fuel flammability parameters, are relatively scarce data. For these reasons, different reanalysis products are often used for the calculation of surrogate fire danger indices, although the agreement with those derived from observations remains as an open question to be addressed.

    In this study, we analyze this problem focusing on the Canadian Fire Weather Index (FWI – and the associated Seasonal Severity Rating (SSR – and considering three different reanalysis products of varying resolutions on the Iberian Peninsula: NCEP, ERA-40 and ERA-Interim. Besides the inter-comparison of the resulting FWI/SSR values, we also study their correspondence with observational data from 7 weather stations in Spain and their sensitivity to the input parameters (precipitation, temperature, relative humidity and wind velocity.

    As a general result, ERA-Interim reproduces the observed FWI magnitudes with better accuracy than NCEP, with lower/higher correlations in the coast/inland locations. For instance, ERA-Interim summer correlations are above 0.5 in inland locations – where higher FWI magnitudes are attained – whereas the corresponding values for NCEP are below this threshold. Nevertheless, departures from the observed distributions are generally found in all reanalysis, with a general tendency to underestimation, more pronounced in the case of NCEP. In spite of these limitations, ERA-Interim may still be useful for the identification of extreme fire danger events. (e.g. those above the 90th percentile value and for the definition of danger levels/classes (with level thresholds adapted to the observed/reanalysis distributions.

  10. Using vegetation indices for soil-moisture retrievals from passive microwave radiometry

    OpenAIRE

    Burke, E J; Shuttleworth, W.J.; French, A.N.

    2001-01-01

    Surface soil moisture and the nature of the overlying vegetation both influence microwave emission from land surfaces significantly. One widely discussed but underused method for allowing for the effect of vegetation on soil-moisture retrievals from microwave observations is to use remotely sensed vegetation indices. This paper explores the potential for using the Normalised Difference Vegetation Index (NDVI) in soil-moisture retrievals from L-band (1.4 GHz) aircraft data gathered during the ...

  11. Impersonality of the Connectivity Index and Recomposition of Topological Indices According to Different Properties

    Directory of Open Access Journals (Sweden)

    Yi-Zeng Liang

    2004-12-01

    Full Text Available The connectivity index χ can be regarded as the sum of bond contributions. Inthis article, boiling point (bp-oriented contributions for each kind of bond are obtainedby decomposing the connectivity indices into ten connectivity character bases and thendoing a linear regression between bps and the bases. From the comparison of bp-orientedcontributions with the contributions assigned by χ, it can be found that they are verysimilar in percentage, i.e. the relative importance of each particular kind of bond is nearlythe same in the two forms of combinations (one is obtained from the regression withboiling point, and the other is decided by the constructor of the χ index. This coincidenceshows an impersonality of χ on bond weighting and may provide us another interpretationof the efficiency of the connectivity index on many quantitative structure–activity/property relationship (QSAR or QSPR results. However, we also found that χ’sweighting formula may not be appropriate for some other properties. In fact, there is nouniversal weighting formula appropriate for all properties/activities. Recomposition ofsome topological indices by adjusting the weights upon character bases according todifferent properties/activities is suggested. This idea of recomposition is applied to thefirst Zagreb group index M1 and a large improvement has been achieved.

  12. The Effect of Pre-Exercise Carbohydrate Feeding with Different Glycemic Index on Endurance Exercise Capacity

    Directory of Open Access Journals (Sweden)

    N. Salarkia

    2004-04-01

    Full Text Available Although, it is known that feeding with carbohydrate (CHO during exercise improves endurance performance, the effects of glycemic index (GI of carbohydrate intake are less clear. This study was carried out to assess the effect of glycemic index of pre-exercise carbohydrate feeding on endurance exercise capacity. In a randomized clinical trial 52 endurance – trained men with mean age 21.7 ± 3 years, weight 69.3 ± 9 kg, height 178.4 ± 2 cm and BMI 22.6 ± 2 were studied. Subjects performed exercise treadmill at 70% VO2max after ingestion: Lentil, a low glycemic index; potato, a high glycemic index; glucose and water (as a control one hour before exercise. Blood samples were collected before and one hour after test meal and 30 minutes after exercise. To assess aerobic capacity VO2max (maximum oxygen uptake was measured at the end of the exercise trial. Endurance time was found to be longer after lentil than after the potato, glucose and control respectively (P < 0.05. At the end of exercise, the glucose group and control both gave lower plasma glucose concentrations. Changes of VO2max in lentil. Potato, glucose and control group which were not statistically significant. This study showed that a low GI meal eaten before an event increases endurance capacity during exercise. Furthermore, the low GI meal was found to maintain glucose at higher concentrations during the later stages of exercise.

  13. Nitrogen fixation in seedlings of sabia and leucena grown in the caatinga soils under different vegetation covers

    International Nuclear Information System (INIS)

    The aim of this study was to evaluate the efficiency differences of populations forming bacteria in legume nodules (BNL) in areas under different vegetation cover in semi-arid Pernambuco state, Brazil, using the methodology of the natural abundance of 15N to estimate the amount of N fixed symbiotically. The highest levels of nitrogen was found in plants of leucena, and the sabia had levels that did not differ from reference species. The analysis by the technique of 15N showed that in all areas the leucena and the sabia showed signs of 15N different of the average signal of the control plants. The largest nitrogen accumulation was observed for leucena in the Caatinga and Capoeira. The sabia got greater accumulation of N from the Caatinga. The areas of Capoeira and Caatinga has showed the native populations of rhizobia with greater ability to fix nitrogen for the leucena

  14. Evaluation of the Cervical Vertebrae Maturation Index in Lateral Cephalograms Taken in Different Head Positions

    Scientific Electronic Library Online (English)

    Fernando Cesar, Torres; Marcos Shinao, Yamazaki; Renata Pilli, Joias; Luiz Renato, Paranhos; Sigmar de Mello, Rode; Danilo Furquim, Siqueira; Acacio, Fuziy.

    2013-09-01

    Full Text Available O objetivo deste estudo foi avaliar se a inclinação da cabeça para cima ou para baixo interfere na determinação do estágio de crescimento por meio do Índice de maturação das vértebras cervicais (IMVC), verificando a acurácia deste método de diagnóstico, quando as radiografias são tomadas com erros. [...] Quarenta e nove pacientes, 26 do gênero feminino e 23 do masculino, entre 9 e 15 anos de idade, foram submetidos a 3 telerradiografias em norma lateral: posição natural de cabeça (PNC), cabeça inclinada 15° para cima (PNC-alta), e 15° para baixo (PNC-baixa). Três examinadores avaliaram o IMVC nas 147 telerradiografias. A concordância entre os examinadores foi alta na avaliação das telerradiografias obtidas em PNC. O teste Kappa revelou concordância moderada a substancial entre PNC e PNC-alta e entre PNC e PNC-baixa. Houve concordância significante entre PNC-alta e PNC-baixa. Pode-se concluir que a avaliação do IMVC em telerradiografias obtidas em PNC difere em comparação com as radiografias tomadas com inclinações. Tanto PNC-alta quanto PNC-baixa demonstraram maior discordância na interpretação entre os examinadores, uma vez que o método de avaliação não foi preconizado para telerradiografias com erros de posicionamento. Abstract in english The aim of this study was to evaluate if upward or downward head inclination might interfere with determination of the growth stage, using cervical vertebrae maturation index (CVMI), in order to verify the accuracy of such diagnosis when radiographs are taken with errors. Forty-nine patients, 26 fem [...] ales and 23 males, aged 9 to 15 years, were submitted to 3 lateral cephalograms: normal (NHP), with 15° upward head inclination (NHP-Up), and with 15° downward head inclination (NHP-Down). Three examiners evaluated the CVMI on the 147 cephalograms. The agreement among examiners was higher in the evaluation of cephalograms taken in NHP. The weighted Kappa test revealed moderate to substantial agreement between NHP and NHP-Up and between NHP and NHP-Down. There was greater agreement between NHP-Up and NHP-Down. It may be concluded that the evaluation of the CVMI on cephalograms in NHP is different as compared with radiographs taken with inclinations. Both NHP-Up and NHP-Down exhibited greater disagreement in the interpretation among examiners, since the evaluation method was not designed for cephalograms with positioning errors.

  15. Comparison of broad-band and narrow-band red and near-infrared vegetation indices

    International Nuclear Information System (INIS)

    An experiment has been conducted in which narrow-band field reflectance spectra were acquired of a rooted pinyon pine canopy with five different gravel backgrounds. Leaf area was successively removed as the measurements were repeated. From these reflectance spectra, narrow-band and broad-band (AVHRR, TM, MSS) red and near-infrared (NIR) vegetation index values were calculated. The performance of the vegetation indices was evaluated based on their capability to accurately estimate leaf area index (LAI) and percent green cover. Background effects were found for each of the tested vegetation indices. However, the background effects are most pronounced in the normalized difference vegetation index (NDVI) and ratio vegetation index (RVI). Background effects can be reduced using either the perpendicular vegetation index (PVI) or soil adjusted vegetation index (SAVI) formulations. The narrow-band versions of these vegetation indices had only slightly better accuracy than their broad-band counterparts. The background effects were minimized using derivative based vegetation indices, which measure the amplitude of the chlorophyll red-edge using continuous narrow-band spectra from 626 nm to 795 nm. (author)

  16. [Fatty acid composition of lipids of vegetative organs of Nigella at different levels of environment salinization].

    Science.gov (United States)

    Gogue, D O; Sidorov, R A; Tsydendambaev, V D; Kholodova, V P; Kuznetsov, V V

    2014-01-01

    A comparative study of the tolerance of two species of medicinal plants of the genus Nigella (N. damascene L. and N. sativa L.) to salt stress was performed. It is shown that growing of plants in the presence of 70 or 110 mM NaCl suppressed the growth and accumulation of dry weight of leaves and roots in both species studied and that this suppression was more pronounced at the higher NaCl concentration. It is established that the salt stress leads to the accumulation of proline in leaves and to a change in the fatty acids composition of lipids in the vegetative parts of plants. It is noted that N. sativa has a higher salt tolerance (70-100 mM NaCl) than N. damascena. It is found that the removal of NaCI from the culture medium and subsequent cultivation of plants exposed to salt stress in a salt-free medium led to a gradual recovery of both Nigella species studied. N. sativa plants showed a high ability for recovery (regeneration) after a strong salt stress. PMID:25731037

  17. Influence of animal fat substitution by vegetal fat on Mortadella-type products formulated with different hydrocolloids

    Directory of Open Access Journals (Sweden)

    Erick Saldaña

    2015-12-01

    Full Text Available Meat has played a crucial role in human evolution and is an important component of a healthy and well-balanced diet on account of its nutritional properties, its high biological value as a source of protein, and the vitamins and minerals it supplies. We studied the effects of animal fat reduction and substitution by hydrogenated vegetal fat, sodium alginate and guar gum. Fatty acid composition, lipid oxidation, color and instrumental texture as well as the sensorial difference between low, substituted-fat and the traditional formulations for mortadella-type products were analyzed. Both substitution and reduction of animal fat decreased the saturated fatty acids percentage from 40% down to 31%. A texture profile analysis showed differences between the formulations. Furthermore, lipid oxidation values were not significant for treatments as regards the type and quantity of fat used while the use of sodium alginate and guar gum reduced the amounts of liquid released after cooking. Animal fat substitution does cause, however, a difference in overall sensorial perception compared with non-substituted products. The results confirm the viability of substituting vegetal fat for animal fat.

  18. New spectral vegetation indices based on the near-infrared shoulder wavelengths for remote detection of grassland phytomass.

    Science.gov (United States)

    Vescovo, Loris; Wohlfahrt, Georg; Balzarolo, Manuela; Pilloni, Sebastian; Sottocornola, Matteo; Rodeghiero, Mirco; Gianelle, Damiano

    2012-04-10

    This article examines the possibility of exploiting ground reflectance in the near-infrared (NIR) for monitoring grassland phytomass on a temporal basis. Three new spectral vegetation indices (infrared slope index, ISI; normalized infrared difference index, NIDI; and normalized difference structural index, NDSI), which are based on the reflectance values in the H25 (863-881 nm) and the H18 (745-751 nm) Chris Proba (mode 5) bands, are proposed. Ground measurements of hyperspectral reflectance and phytomass were made at six grassland sites in the Italian and Austrian mountains using a hand-held spectroradiometer. At full canopy cover, strong saturation was observed for many traditional vegetation indices (normalized difference vegetation index (NDVI), modified simple ratio (MSR), enhanced vegetation index (EVI), enhanced vegetation index 2 (EVI 2), renormalized difference vegetation index (RDVI), wide dynamic range vegetation index (WDRVI)). Conversely, ISI and NDSI were linearly related to grassland phytomass with negligible inter-annual variability. The relationships between both ISI and NDSI and phytomass were however site specific. The WinSail model indicated that this was mostly due to grassland species composition and background reflectance. Further studies are needed to confirm the usefulness of these indices (e.g. using multispectral specific sensors) for monitoring vegetation structural biophysical variables in other ecosystem types and to test these relationships with aircraft and satellite sensors data. For grassland ecosystems, we conclude that ISI and NDSI hold great promise for non-destructively monitoring the temporal variability of grassland phytomass. PMID:24347746

  19. Assessment of soil biological quality index (QBS-ar) in different crop rotation systems in paddy soils

    Science.gov (United States)

    Nadimi-Goki, Mandana; Bini, Claudio; haefele, Stephan

    2013-04-01

    New methods, based on soil microarthropods for soil quality evaluation have been proposed by some Authors. Soil microarthropods demonstrated to respond sensitively to land management practices and to be correlated with beneficial soil functions. QBS Index (QBS-ar) is calculated on the basis of microarthropod groups present in a soil sample. Each biological form found in the sample receives a score from 1 to 20 (eco-morphological index, EMI), according to its adaptation to soil environment. The objective of this study was to evaluate the effect of various rotation systems and sampling periods on soil biological quality index, in paddy soils. For the purpose of this study surface soil samples (0-15 cm depth) were collected from different rotation systems (rice-rice-rice, soya-rice-rice, fallow-rice and pea-soya-rice) with three replications, and four sampling times in April (after field preparation), June (after seedling), August (after tillering stage) and October (after rice harvesting). The study area is located in paddy soils of Verona area, Northern Italy. Soil microarthropods from a total of 48 samples were extracted and classified according to the Biological Quality of Soil Index (QBS-ar) method. In addition soil moisture, Cumulative Soil Respiration and pH were measured in each site. More diversity of microarthropod groups was found in June and August sampling times. T-test results between different rotations did not show significant differences while the mean difference between rotation and different sampling times is statistically different. The highest QBS-ar value was found in the fallow-rice rotation in the forth soil sampling time. Similar value was found in soya-rice-rice rotation. Result of linear regression analysis indicated that there is significant correlation between QBS-ar values and Cumulative Soil Respiration. Keywords: soil biological quality index (QBS-ar), Crop Rotation System, paddy soils, Italy

  20. Determination of surface tension, optical rotativity and refractive index of polymer polyvinyl alcohol PVA, in various solvents at different concentrations

    Directory of Open Access Journals (Sweden)

    Sarojini Panda

    2011-12-01

    Full Text Available Surface tension, Optical Rotativity and Refractive Index of Polymer PVA ( w=1,25,000 in various solvents like distilled water, NaOH, KOH and Urea at different concentrations are measured, which enable us to know the interaction of the polymer molecules in these solvents.

  1. Dissecting the function of the different chitin synthases in vegetative growth and sexual development in Neurospora crassa.

    Science.gov (United States)

    Fajardo-Somera, Rosa A; Jöhnk, Bastian; Bayram, Özgür; Valerius, Oliver; Braus, Gerhard H; Riquelme, Meritxell

    2015-02-01

    Chitin, one of the most important carbohydrates of the fungal cell wall, is synthesized by chitin synthases (CHS). Seven sequences encoding CHSs have been identified in the genome of Neurospora crassa. Previously, CHS-1, -3 and -6 were found at the Spitzenkörper(Spk) core and developing septa. We investigated the functional importance of each CHS in growth and development of N. crassa. The cellular distribution of each CHS tagged with fluorescent proteins and the impact of corresponding gene deletions on vegetative growth and sexual development were compared. CHS-2, -4, -5 and -7 were also found at the core of the Spk and in forming septa in vegetative hyphae. As the septum ring developed, CHS-2-GFP remained at the growing edge of the septum until it localized around the septal pore. In addition, all CHSs were located in cross-walls of conidiophores. A partial co-localization of CHS-1-m and CHS-5-GFP or CHS-2-GFP occurred in the Spk and septa. Analyses of deletion mutants suggested that CHS-6 has a role primarily in hyphal extension and ascospore formation, CHS-5 in aerial hyphae, conidia and ascospore formation, CHS-3 in perithecia development and CHS-7 in all of the aforementioned. We show that chs-7/csmB fulfills a sexual function and chs-6/chsG fulfills a vegetative growth function in N. crassa but not in Aspergillus nidulans, whereas vice versa chs-2/chsA fulfills a sexual function in A. nidulans but not in N. crassa. This suggests that different classes of CHSs can fulfill distinct developmental functions in various fungi. Immunoprecipitation followed by mass spectrometry of CHS-1-GFP, CHS-4-GFP and CHS-5-GFP identified distinct putative interacting proteins for each CHS. Collectively, our results suggest that there are distinct populations of chitosomes, each carrying specific CHSs, with particular roles during different developmental stages. PMID:25596036

  2. Application of AVHRR vegetation index to study atmosphere-biosphere exchange of CO2: Results from a 3-D tracer transport model

    Science.gov (United States)

    Fung, Inez Y.; Tucker, C. J.; Prentice, Katharine C.

    1985-01-01

    The 'normalized difference vegetation indices' (NVI) derived from AVHRR radiances are combined with field data of soil respiration and a global map of net primary productivity to prescribe, for the globe, the seasonal exchange of CO2 between the atmosphere and the terrestrial biosphere. The monthly fluxes of CO2 thus obtained are used as inputs to a 3-D tracer transport model which uses winds generated by a 3-D atmospheric general circulation model to advect CO2 as an inert constituent. Analysis of the 3-D model results shows reasonable agreement between the simulated and observed annual cycles of atmospheric CO2 at the locations of the remote monitoring stations. The application is shown of atmospheric CO2 distributions to calibrate the NVI in terms of carbon fluxes. The approach suggests that the NVI may be used to provide quantitative information about long term and global scale variations of photosynthetic activity and of atmospheric CO2 concentrations provided that variations in the atmospheric circulation and in atmospheric composition are known.

  3. Cooling parameters for fruits and vegetables of different sizes in a hydrocooling system / Parâmetros de resfriamento de frutas e hortaliças de diferentes dimensões em um sitema com água fria

    Scientific Electronic Library Online (English)

    Bárbara, Teruel; Theo, Kieckbusch; Luis, Cortez.

    2004-12-01

    Full Text Available O resfriamento com água gelada pode ser uma técnica adequada para frutas e hortaliças frescas. Este trabalho teve como objetivo obter o tempo de resfriamento de frutas e hortaliças de dimensões diferentes, e apresentar índices práticos que possam ser usados para estimar o tempo de resfriamento de pr [...] odutos com características semelhantes. Frutas (melão-Cucumis melo, manga-Mangifera indica, goiaba-Psidium guajava, laranja-Citrus sinensis Osbeck, ameixa-Prunus domestica, limão-Citrus limon e acerola-Malpighia glabra) e hortaliças (pepino-Cucumis sativus, cenoura-Daucus carota e vagem-Phaseolus vulgaris), foram resfriadas num sistema por imersão em água à 1°C. O volume das frutas oscilou de 1150,35 cm³ a 8,18 cm³ e das hortaliças entre 438,4 cm³ a 13,06 cm³. O tempo de resfriamento variou proporcionalmente com o volume dos frutos, de 8,5 min até 124 min (frutas) e de 1,5 min até 55 min (hortaliças). Foi calculado o índice relacionando volume e tempo de resfriamento das frutas (1,03 min cm-3 a 0,107 min cm-3) e hortaliças (0,06 min cm-3 a 0,12 min cm-3), que pode ser usado para a estimativa do tempo de resfriamento de frutas e hortaliças com dimensões semelhantes. Abstract in english The cooling of fruits and vegetables in hydrocooling system can be a suitable technique. This work aimed to define cooling time for fruits and vegetables of different sizes, presenting practical indexes that could be used to estimate cooling time for produce with similar characteristics. Fruits (ora [...] nge melon-Cucumis melo, mango-Mangifera indica, guava-Psidium guajava, orange-Citrus sinensis Osbeck, plum-Prunus domestica, lime-Citrus limon, and acerola-Prunus cerasus) and vegetables (cucumber-Cucumis sativus, carrot-Daucus carota, and green bean-Phaseolus vulgaris), were cooled in a hydrocooling system at 1°C. The volume of fruits and vegetables ranged between 8.18 cm³ and 1,150.35 cm³, and between 13.06 cm³ and 438.4 cm³, respectively. Cooling time varied proportionally to produce volume (from 8.5 to 124 min for fruits, and from 1.5 to 55 min, for vegetables). The relationship between volume and time needed to cool fruits (from 1.03 min cm-3 to 0.107 min cm-3) and vegetables (from 0.06 min cm-3 to 0.12 min cm-3) is an index that could be used to estimate cooling time for fruits and vegetables with similar dimensions as those presented in this work.

  4. Grazing effects on species composition in different vegetation types (La Palma, Canary Islands)

    Science.gov (United States)

    Arévalo, J. R.; de Nascimento, L.; Fernández-Lugo, S.; Mata, J.; Bermejo, L.

    2011-05-01

    Grazing management is probably one of the most extensive land uses, but its effects on plant communities have in many cases been revealed to be contradictory. Some authors have related these contradictions to the stochastic character of grazing systems. Because of that, it is necessary to implement specific analyses of grazing effects on each community, especially in natural protected areas, in order to provide the best information to managers. We studied the effects of grazing on the species composition of the main vegetation types where it takes place (grasslands, shrublands and pine forests) on the island of La Palma, Canary Islands. We used the point-quadrat intersect method to study the species composition of grazed and ungrazed areas, which also were characterized by their altitude, distance to farms, distance to settlements, year of sampling, herbaceous aboveground biomass and soil organic matter. The variables organic matter, productivity and species richness were not significantly affected by grazing. The species composition of the analyzed plant communities was affected more by variables such as altitude or distance to farms than by extensive grazing that has been traditionally carried out on the island of La Palma involving certain practices such as continuous monitoring of animals by goat keepers, medium stocking rates adjusted to the availability of natural pastures, supplementation during the dry season using local forage shrubs or mown pastures and rotating animals within grazing areas Although some studies have shown a negative effect of grazing on endangered plant species, these results cannot be freely extrapolated to the traditional grazing systems that exert a low pressure on plant communities (as has been found in this study). We consider extensive grazing as a viable way of ensuring sustainable management of the studied ecosystems.

  5. Composition, abundance and richness of sarcophagidae (Diptera: oestroidea) in forests and forest gaps with different vegetation cover.

    Science.gov (United States)

    Sousa, J R P de; Esposito, M C; Carvalho Filho, F S

    2011-01-01

    This study was carried out in the Base Operacional Geólogo Pedro de Moura (BOGPM) in the Urucu River Basin, Coari, state of Amazonas, Brazil, during April, June, and October 2007, in 16 areas, 4 in primary forests (environment MT) and 12 in gaps (environments C1, C2, and C3) at different stages of vegetation recovery, with different plant cover height. We collected 3,547 specimens of flesh flies. The 3,525 individuals identified to species level included 10 genera, 6 subgenera, and 23 species. Sarcodexia lambens (Wiedemann) (47.1%) and Peckia (Peckia) chrysostoma (Wiedemann) (19.1%) were the most abundant species. The abundance patterns and estimated richness differed between the environments, and were separated in two groups, one of the gaps (C1, C2, and C3) and another of forests (MT). Both abundance and estimated richness were higher in the gaps (C1, C2, and C3) than in the forest (MT). PMID:21437478

  6. Feed intake and activity level of two broiler genotypes foraging different types of vegetation in the finishing period

    DEFF Research Database (Denmark)

    de Almeida, Gustavo Fonseca; Hinrichsen, Lena Karina; Horsted, Klaus; Thamsborg, Stig Milan; Hermansen, John Erik

    2012-01-01

    were included in a 2 × 2 factorial design with groups of 25 birds replicated 3 times. The use of outdoor areas, performance, and forage intake were investigated. To identify possible differences in foraging activity, the use of the range was monitored one day per week at 4 different times of the day...... day with increased foraging activity during evenings, in contrast to the slow-growing broilers that showed a more uniform activity during the day. Based on the measurement of crop content it was estimated that the slow-growing genotype had a daily intake of 5 to 8 g of forage per day, whereas the....... Feed intake from foraging was estimated by killing 4 birds per plot (2 males and 2 females) in the morning and in the evening on 3 d during the experiment and measuring crop content. Vegetation type did not influence broiler use of the free-range area, feed intake, or performance. Differences in the...

  7. Comparison of different ground techniques to map leaf area index of Norway spruce forest canopy.

    Czech Academy of Sciences Publication Activity Database

    Homolová, Lucie; Malenovský, Zbyn?k; Hanuš, Jan; Tomášková, Ivana; Dvo?áková, Marcela; Pokorný, Radek

    2007 - (Schaepman, M.; Liang, S.; Groot, N.; Kneubühler, M.) ISSN 1682-1777. - (Intl. Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences. 36). [10th Intl. Symposium on Physical Measurements and Spectral Signatures in Remote Sensing. Davos (CH), 12.03.2007-14.03.2007] Institutional research plan: CEZ:AV0Z60870520 Keywords : leaf area index * sampling strategy * PCA LAI-2000 * TRAC * hemispherical photograph * Norway spruce Subject RIV: GK - Forestry

  8. Vegetation against dune mobility

    OpenAIRE

    Duran, Orencio; Herrmann, Hans J.

    2006-01-01

    Vegetation is the most common and most reliable stabilizer of loose soil or sand. This ancient technique is for the first time cast into a set of equations of motion describing the competition between aeolian sand transport and vegetation growth. Our set of equations is then applied to study quantitatively the transition between barchans and parabolic dunes driven by the dimensionless fixation index $\\theta$ which is the ratio between dune characteristic erosion rate and vegetation growth vel...

  9. Timing of Peak Blood Glucose after Breakfast Meals of Different Glycemic Index in Women with Gestational Diabetes

    OpenAIRE

    Deborah Foote; Jennie C. Brand-Miller; Glynis P. Ross; Markovic, Tania P; Jimmy Chun Yu Louie

    2012-01-01

    This study aims to determine the peak timing of postprandial blood glucose level (PBGL) of two breakfasts with different glycemic index (GI) in gestational diabetes mellitus (GDM). Ten women with diet-controlled GDM who were between 30 and 32 weeks of gestation were enrolled in the study. They consumed two carbohydrate controlled, macronutrient matched bread-based breakfasts with different GI (low vs. high) on two separate occasions in a random order after an overnight fast. PBGLs were assess...

  10. Evaluation of MODIS NDVI and NDWI for vegetation drought monitoring using Oklahoma Mesonet soil moisture data

    Science.gov (United States)

    Gu, Yingxin; Hunt, Eric; Wardlow, Brian; Basara, Jeffrey B.; Brown, Jesslyn F.; Verdin, James P.

    2008-11-01

    The evaluation of the relationship between satellite-derived vegetation indices (normalized difference vegetation index and normalized difference water index) and soil moisture improves our understanding of how these indices respond to soil moisture fluctuations. Soil moisture deficits are ultimately tied to drought stress on plants. The diverse terrain and climate of Oklahoma, the extensive soil moisture network of the Oklahoma Mesonet, and satellite-derived indices from the Moderate Resolution Imaging Spectroradiometer (MODIS) provided an opportunity to study correlations between soil moisture and vegetation indices over the 2002-2006 growing seasons. Results showed that the correlation between both indices and the fractional water index (FWI) was highly dependent on land cover heterogeneity and soil type. Sites surrounded by relatively homogeneous vegetation cover with silt loam soils had the highest correlation between the FWI and both vegetation-related indices (r~0.73), while sites with heterogeneous vegetation cover and loam soils had the lowest correlation (r~0.22).

  11. Reflection statistics of weakly disordered optical medium when its mean refractive index is different from an outside medium

    CERN Document Server

    Pradhan, Prabhakar; Capoglu, Ilker; Subramanian, Hariharan; Damania, Dhwanil; Cherkezyan, Lusik; Taflove, Allen; Backman, Vadim

    2015-01-01

    Based on the difference between mean background of an optical sample refractive index n_0 and an outside medium, n_out, different than n_0, we study the reflection statistics of a one-dimensional weakly disordered optical medium with refractive index n(x)=n_0+dn(x). Considering dn(x) as color noise with the exponential spatial correlation decay length l_c and k as the incident wave vector, our results show that for the small correlation length limit, i.e. k*l_c proportional to l_c. However, the standard deviation of r is proven to be std(r(dn,l_c)) proportional to sqrt(l_c), which is different from the matched case. Applications to light scattering from layered media and biological cells are discussed

  12. Climate change, growing season water deficit and vegetation activity along the north-south transect of Eastern China from 1982 through 2006

    OpenAIRE

    Sun, P; Yu, Z; Liu, S.; Wei, X; Wang, J.; N. Zegre

    2012-01-01

    Considerable work has been done to examine the relationship between environmental constraints and vegetation activities represented by the remote sensing-based Normalized Difference Vegetation Index (NDVI). However, the relationships along either environmental or vegetation type gradients are rarely examined. The aim of this paper was to identify the vegetation types that are potentially susceptible to climate change through examining the interaction between vegetation activity and wa...

  13. The influence of slope and peatland vegetation type on riverine dissolved organic carbon and water colour at different scales.

    Science.gov (United States)

    Parry, L E; Chapman, P J; Palmer, S M; Wallage, Z E; Wynne, H; Holden, J

    2015-09-15

    Peatlands are important sources of fluvial carbon. Previous research has shown that riverine dissolved organic carbon (DOC) concentrations are largely controlled by soil type. However, there has been little work to establish the controls of riverine DOC within blanket peatlands that have not undergone major disturbance from drainage or burning. A total of 119 peatland catchments were sampled for riverine DOC and water colour across three drainage basins during six repeated sampling campaigns. The topographic characteristics of each catchment were determined from digital elevation models. The dominant vegetation cover was mapped using 0.5m resolution colour infrared aerial images, with ground-truthed validation revealing 82% accuracy. Forward and backward stepwise regression modelling showed that mean slope was a strong (and negative) determinant of DOC and water colour in blanket peatland river waters. There was a weak role for plant functional type in determining DOC and water colour. At the basin scale, there were major differences between the models depending on the basin. The dominance of topographic predictors of DOC found in our study, combined with a weaker role of vegetation type, paves the way for developing improved planning tools for water companies operating in peatland catchments. Using topographic data and aerial imagery it will be possible to predict which tributaries will typically yield lower DOC concentrations and which are therefore more suitable and cost-effective as raw water intakes. PMID:26003614

  14. The Influence of Different Vegetable Oils on Some ?-3 Polyunsaturated Fatty Acids from Thigh and Abdominal Fat of Broilers

    Directory of Open Access Journals (Sweden)

    Drago? Sorin Fota

    2011-05-01

    Full Text Available Energy sources, especialy vegetable oils, added to the combined fodder can segnificantly modefy the fatty acids profile of the chicken feed, thus through its control the fatty acids profile of the carcases can be modefied, through enrichment in some fatty acids. In this respect an experiment was coduced on broilers, made up of three experimental groups, fed with a combined base fodder (corn and soybean meal in which 2% of different energy sources were added (sunflower oil, soybean oil, linseed oil. At the end of the 42 days growing period, using gaz cromatography, the fatty acids profile, % of fatty acids in 100 g product (EPA,DPA, DHA, ? SFA, ? MUFA, ? PUFA from the studied cut pieces, were determined. The results obtained after statistc processing and interpretation of the data, showed the fact that regarding the fatty acids profile in chicken thigh and abdominal fat we can observe variations, what denotes that the fatty acids profile can be influenced by dietary factors, the quantity being yet determined by the participation % of the energy sources (vegetable oils, but also by the fatty acids content of the participating raw materials.

  15. Fractal Characteristics of Soil Retention Curve and Particle Size Distribution with Different Vegetation Types in Mountain Areas of Northern China.

    Science.gov (United States)

    Niu, Xiang; Gao, Peng; Wang, Bing; Liu, Yu

    2015-01-01

    Based on fractal theory, the fractal characteristics of soil particle size distribution (PSD) and soil water retention curve (WRC) under the five vegetation types were studied in the mountainous land of Northern China. Results showed that: (1) the fractal parameters of soil PSD and soil WRC varied greatly under each different vegetation type, with Quercus acutissima Carr. and Robina pseudoacacia Linn. mixed plantation (QRM) > Pinus thunbergii Parl. and Pistacia chinensis Bunge mixed plantation (PPM) > Pinus thunbergii Parl. (PTP) > Juglans rigia Linn. (JRL) > abandoned grassland (ABG); (2) the soil fractal dimensions of woodlands (QRM, PPM, PTP and JRL) were significantly higher than that in ABG, and mixed forests (QRM and PPM) were higher than that in pure forests (PTP and JRL); (3) the fractal dimension of soil was positively correlated with the silt and clay content but negatively correlated with the sand content; and (4) the fractal dimension of soil PSD was positively correlated with the soil WRC. These indicated that the fractal parameters of soil PSD and soil WRC could act as quantitative indices to reflect the physical properties of the soil, and could be used to describe the influences of the Return Farmland to Forests Projects on soil structure. PMID:26633458

  16. Fractal Characteristics of Soil Retention Curve and Particle Size Distribution with Different Vegetation Types in Mountain Areas of Northern China

    Directory of Open Access Journals (Sweden)

    Xiang Niu

    2015-12-01

    Full Text Available Based on fractal theory, the fractal characteristics of soil particle size distribution (PSD and soil water retention curve (WRC under the five vegetation types were studied in the mountainous land of Northern China. Results showed that: (1 the fractal parameters of soil PSD and soil WRC varied greatly under each different vegetation type, with Quercus acutissima Carr. and Robina pseudoacacia Linn. mixed plantation (QRM > Pinus thunbergii Parl. and Pistacia chinensis Bunge mixed plantation (PPM > Pinus thunbergii Parl. (PTP > Juglans rigia Linn. (JRL > abandoned grassland (ABG; (2 the soil fractal dimensions of woodlands (QRM, PPM, PTP and JRL were significantly higher than that in ABG, and mixed forests (QRM and PPM were higher than that in pure forests (PTP and JRL; (3 the fractal dimension of soil was positively correlated with the silt and clay content but negatively correlated with the sand content; and (4 the fractal dimension of soil PSD was positively correlated with the soil WRC. These indicated that the fractal parameters of soil PSD and soil WRC could act as quantitative indices to reflect the physical properties of the soil, and could be used to describe the influences of the Return Farmland to Forests Projects on soil structure.

  17. Animal and vegetal pole cells of early Xenopus embryos respond differently to maternal dorsal determinants: implications for the patterning of the organiser

    International Nuclear Information System (INIS)

    The maternal dorsal determinants required for the specification of the dorsal territories of Xenopus early gastrulae are located at the vegetal pole of unfertilised eggs and are moved towards the prospective dorsal region of the fertilised egg during cortical rotation. While the molecular identity of the determinants is unknown, there are dorsal factors in the vegetal cortical cytoplasm (VCC). Here, we show that the VCC factors, when injected into animal cells activate the zygotic genes Siamois and Xnr3, suggesting that they act along the Wnt/?-catenin pathways. In addition, Siamois and Xnr3 are activated and at the vegetal pole of UV-irradiated embryos, indicating that these two genes are targets of the VCC factors in all embyronic cells. However, the consequences of their activation in cells that occupy different positions along the animal-vegetal axis differ. Dorsal vegetal cells of normal embryos or VCC-treated injected animal cells are able to dorsalise ventral mesoderm in conjugate experiments but UV-treated vegetal caps do not have this property. We propose that the regionalisation of the organiser during gastrulation proceeds from the differential interpretation along the animal-vegetal axis of the activation of the VCC/?-catenin/Siamois pathway. (author)

  18. Glycemic index differences of high-fat diets modulate primarily lipid metabolism in murine adipose tissue.

    Science.gov (United States)

    van Schothorst, Evert M; Bunschoten, Annelies; Verlinde, Eline; Schrauwen, Patrick; Keijer, Jaap

    2011-08-16

    A low vs. high glycemic index of a high-fat (HF) diet (LGI and HGI, respectively) significantly retarded adverse health effects in adult male C57BL/6J mice, as shown recently (Van Schothorst EM, Bunschoten A, Schrauwen P, Mensink RP, Keijer J. FASEB J 23: 1092-1101, 2009). The LGI diet enhanced whole body insulin sensitivity and repressed HF diet-induced body and white adipose tissue (WAT) weight gain, resulting in significantly reduced serum leptin and resistin levels and increased adiponectin levels. We questioned how WAT is modulated and characterized the molecular mechanisms underlying the glycemic index-mediated effects using whole genome microarrays. This showed that the LGI diet mainly exerts its beneficial effects via substrate metabolism, especially fatty acid metabolism. In addition, cell adhesion and cytoskeleton remodeling showed reduced expression, in line with lower WAT mass. An important transcription factor showing enhanced expression is PPAR-?. Furthermore, serum levels of triglycerides, total cholesterol, and HDL- and LDL-cholesterol were all significantly reduced by LGI diet, and simultaneously muscle insulin sensitivity was significantly increased as analyzed by protein kinase B/Akt phosphorylation. Cumulatively, even though these mice were fed an HF diet, the LGI diet induced significantly favorable changes in metabolism in WAT. These effects suggest a partial overlap with pharmacological approaches by thiazolidinediones to treat insulin resistance and statins for hypercholesterolemia. It is therefore tempting to speculate that such a dietary approach might beneficially support pharmacological treatment of insulin resistance or hypercholesterolemia in humans. PMID:21673076

  19. Exposition index calculation from different points in a gamma sterilization plant radiation room

    International Nuclear Information System (INIS)

    Radiation fields produced by a JS-6500 rectangular irradiator source were evaluated. Knowledge of the values of these fields is necessary in irradiation and health physics processes. Techniques for evaluating the dose rates from puntual, linear and plane sources were applied and computer programs for the three sources designed. Fricke, cupric-ferrous and red acrilic dosimetric systems were used, to verify the eight points located along the interior walls of the irradiation room, around the source with 936, 987 Ci of Co-60 (1st-March 1980). When considering the distance between the source and each point of interest the calculated exposition indexes obtained were practically the same for the three source types and were up to 35% greater than the experimental values; in contrast when absorption and buildup of the source were taken in to account, the experimental values were higher than the calculated ones by up to 16%, this in estimating the produced exposition index for a rectangular source at least there two parameters should be included. (author)

  20. Intercommunications of indexes of general physical training of fencer on swords different qualifying groups.

    Directory of Open Access Journals (Sweden)

    Hohla A.I.

    2012-10-01

    Full Text Available Purpose of work - to find out the presence of cross-correlation intercommunications between the indexes of general physical preparedness and dependence of their structure from the level of sporting qualification of sportsmen. 66 sportsmen took part in research. From them 35 are sportsmen of I-II of digits, 31 are highly skilled sportsmen. Sportsmen executed 14 tests which characterize the level of general physical preparedness. For the sportsmen of spark-gaps found out 15 reliable cross-correlation intercommunications of direct (10 and reverse (5 character. For skilled sportsmen - 18: (9 direct and (9 reverse character. For the sportsmen of spark-gaps the most of reliable intercommunications is set between spray force (6 and explosive force of feet (5. At skilled - between figure (7 and spray (6 force and other indexes. The presence of direct cross-correlation intercommunications between physical qualities testifies about expedience of their complex development in one training employment. Reverse - about the necessity of the differentiated development of such physical qualities.

  1. Agronomic characteristics associated with vegetation index measured by active sensors of the canopy in soybeanCaracterísticas agronômicas associadas com índices de vegetação medidos por sensores ativos de dossel na cultura da soja

    Directory of Open Access Journals (Sweden)

    Edson Cristiano Groff

    2013-05-01

    Full Text Available Soybean has always stood out for its economic importance in the national agricultural scenario with an increase in its cultivation throughout the Brazilian territory. With the increasing use of precision agriculture (PA is of paramount importance to understand the variability of agronomic variables. Currently, spectral sensors in the ground-level have been used to establish relationships between spectral response and crop growth parameters. This is possible through the reading of vegetation indices such as Normalized Difference Vegetation Index using the green band (GNDVI. This study was conducted between October to 2008 and April to 2009, in Ponta Grossa – PR, with the objective of evaluating the spectral response of soybean through GNDVI and its correlation with some agronomic variables, such as: productivity of grain, productivity of dry mass, plant density and plant height. GNDVI readings were taken on six phenological stages using Crop Circle active optical sensor. Regression analyzes were used to determine which agronomic variables established relationship with the GNDVI. The GNDVI in soybean established significant correlations only with grain and MS productivity in EF V9. Thus, to establish the correlation of GNDVI with these variables it is recommended that the readings are carried out in this EF.A soja sempre se destacou pela sua importância econômica no cenário agrícola nacional tendo sido observado aumento do seu cultivo em todo o território brasileiro. Com o uso crescente da agricultura de precisão (AP é de suma importância entender a variabilidade das variáveis agronômicas. Atualmente, sensores espectrais em nível terrestre vêm sendo utilizados para estabelecer relações entre as respostas espectrais e parâmetros de crescimento da cultura. Isso é possível por meio da leitura dos índices de vegetação, como o Índice de Vegetação da Diferença Normalizada utilizando a banda verde (GNDVI. Este estudo foi conduzido entre outubro de 2008 e abril de 2009, em Ponta Grossa – PR, com o objetivo de avaliar a resposta espectral da cultura da soja por meio do GNDVI e sua correlação com algumas variáveis agronômicas, como: produtividade de grãos, produtividade de massa seca, densidade de plantas e altura de plantas. Leituras do GNDVI foram realizadas em seis estádios fenológicos (EF utilizando o sensor óptico ativo Crop Circle. Análises de regressão foram utilizadas para determinar quais variáveis agronômicas estabeleciam relação com o GNDVI. O GNDVI na cultura da soja estabeleceu correlações significativas apenas com a produtividade de grãos e a produtividade de MS no EF V9. Assim, para se estabelecer a correlação do GNDVI com essas variáveis recomenda-se que as leituras sejam realizadas nesse EF.

  2. Mercury methylation in sediments of a Brazilian mangrove under different vegetation covers and salinities.

    Science.gov (United States)

    de Oliveira, Diana Ciannella Martins; Correia, Raquel Rose Silva; Marinho, Claudio Cardoso; Guimarães, Jean Remy Davée

    2015-05-01

    The presence and formation of methylmercury (MMHg), a highly toxic form of Hg, in mangrove ecosystems is poorly studied. Therefore the aim of this study was to evaluate mercury methylation potentials in sediment, litter and root samples (Avicennia shaueriana and Spartina alterniflora) from different regions of a mangrove ecosystem, as well as the influence of salinity on methylation. Sediment was sampled under different depths and in mangrove regions with different plant covers and salinities. All samples were incubated with (203)Hg and MM(203)Hg was extracted and measured by liquid scintillation. MMHg was formed in all samples and sites tested including plant roots and litter. Higher Hg methylation was found in the superficial fraction of sediments (0.47-7.82%). Infralittoral sandy sediment had low MMHg formation (0.44-1.61%). Sediment under Rhizophora mangle had lower MMHg formation (0.018-2.23%) than under A. shaueriana (0.2-4.63%) and Laguncularia racemosa (0.08-7.82). MMHg formation in sediment tended to increase with salinity but the differences were not significant. Therefore, MMHg formation occurs in different sites of mangrove ecosystems and may be an important threat that requires further study. PMID:25732633

  3. Vegetation against dune mobility

    CERN Document Server

    Duran, O; Duran, Orencio; Herrmann, Hans J.

    2006-01-01

    Vegetation is the most common and most reliable stabilizer of loose soil or sand. This ancient technique is for the first time cast into a set of equations of motion describing the competition between aeolian sand transport and vegetation growth. Our set of equations is then applied to study quantitatively the transition between barchans and parabolic dunes driven by the dimensionless fixation index $\\theta$ which is the ratio between dune characteristic erosion rate and vegetation growth velocity. We find a fixation index $\\theta_c$ below which the dunes are stabilized characterized by scaling laws.

  4. Factors affecting the wettability of different surface materials with vegetable oil at high temperatures and its relation to cleanability

    DEFF Research Database (Denmark)

    Ashokkumar, Saranya; Adler-Nissen, Jens

    2012-01-01

    The main aim of the work was to investigate the wettability of different surface materials with vegetable oil (olive oil) over the temperature range of 25–200°C to understand the differences in cleanability of different surfaces exposed to high temperatures in food processes. The different surface materials investigated include stainless steel (reference), PTFE (polytetrafluoroethylene), silicone, quasicrystalline (Al, Fe, Cr) and ceramic coatings: zirconium oxide (ZrO2), zirconium nitride (ZrN) and titanium aluminum nitride (TiAlN). The ceramic coatings were deposited on stainless steel with two different levels of roughness. The cosine of the contact angle of olive oil on different surface materials rises linearly with increasing temperature. Among the materials analyzed, polymers (PTFE, silicone) gave the lowest cos? values. Studies of the effect of roughness and surface flaws on wettability revealed that the cos? values increases with increasing roughness and surface flaws. Correlation analysis indicates that the measured contact angle values gave useful information for grouping easy-clean polymer materials from the other materials; for the latter group, there is no direct relation between contact angle and cleanability. In addition to surface wettability with oil many other factors such as roughness and surface defects play an essential role in determining their cleanability.

  5. Simulation of the interaction between the atmosphere, vegetation and the Earth's surface in different parameterisation concepts; Simulation der Wechselwirkung zwischen Atmosphaere, Vegetation und Erdoberflaeche bei Verwendung unterschiedlicher Parametrisierungsansaetze

    Energy Technology Data Exchange (ETDEWEB)

    Grabe, F.

    2002-01-01

    The purpose of the present study was to compare two soil vegetation models based on entirely different concepts, namely the ''VEG3D'' model of the Institute of Meteorology and Climate Research of Karlsruhe University and the TERRA model of the German weather service. VEG3D comprises a multilayer soil model which calculates prognostic equations for soil heat and water flows and a vegetation layer in which the vegetation is represented by a single large leaf, in accordance with Deardorff's reference leaf concept (1976). TERRA is a two-layer soil model which calculates soil temperatures by means of the ''Extended Force Restore Method''. TERRA takes account of the vegetation by allowing the properties of the soil surface to change like a vegetation-bearing surface does. [German] Es war das Ziel dieser Arbeit, zwei Bodenvegetationsmodelle mit voellig unterschiedlichen Konzeptionen miteinander zu vergleichen. Bei diesen Modellen handelt es sich um das 'VEG3D' des Instituts fuer Meteorologie und Klimaforschung der Universitaet Karlsruhe und um das 'TERRA' des Deutschen Wetterdienstes. Das VEG3D beinhaltet ein mehrschichtiges Bodenmodell, in dem die prognostischen Gleichungen fuer Bodenwaerme- und Bodenwasserstroeme berechnet werden, sowie eine Bestandsschicht, in der die Vegetation nach dem Referenzblatt-Konzept von Deardorff (1976) durch ein einzelnes, grosses Blatt dargestellt wird. Das TERRA ist ein zweischichtiges Bodenmodell, welches die Bodentemperaturen ueber die 'Extended-Force-Restore Methode' berechnet. Vegetation wird in TERRA beruecksichtigt, in dem die Eigenschaften der Bodenoberflaeche so veraendert werden, dass sie sich verhaelt wie eine bewachsene Oberflaeche. (orig.)

  6. Thermodynamic study of three pharmacologically significant drugs: Density, viscosity, and refractive index measurements at different temperatures

    International Nuclear Information System (INIS)

    Measurements of density, viscosity, and refractive index of three pharmacologically significant drugs, i.e. diclofenac sodium, cetrizine, and doxycycline have been carried in aqueous medium at T = (293.15 to 313.15) K. An automated vibrating-tube densimeter, viscometer, and refractometer are used in a concentration range from (7.5) . 10-3 to 25 . 10-3) mol . kg-1. The precise density results are used to evaluate the apparent molar volume, partial molar volume, thermal expansion coefficient, partial molar expansivity, and the Hepler's constant. Viscosity results are used to calculate the Jones-Dole viscosity B-coefficient, free energy of activation of the solute and solvent, activation enthalpy, and activation entropy. The molar refractive indices of the drug solutions can be employed to calculate molar refraction. It is inferred from these results that the above mentioned drugs act as structure-making compounds due to hydrophobic hydration of the molecules in the drugs

  7. Transmission of Light in Crystals with different homogeneity: Using Shannon Index in Photonic Media

    CERN Document Server

    Bellingeri, Michele; Scotognella, Francesco

    2010-01-01

    Light transmission in inhomogeneous photonic media is strongly influenced by the distribution of the diffractive elements in the medium. Here it is shown theoretically that, in a pillar photonic crystal structure, light transmission and homogeneity of the pillar distribution are correlated by a simple linear law once the grade of homogeneity of the photonic structure is measured by the Shannon index, widely employed in statistics, ecology and information entropy. The statistical analysis shows that the transmission of light in such media depends linearly from their homogeneity: the more is homogeneous the structure, the more is the light transmitted. With the found linear relationship it is possible to predict the transmission of light in random photonic structures. The result can be useful for the study of electron transport in solids, since the similarity with light in photonic media, but also for the engineering of scattering layers for the entrapping of light to be coupled with photovoltaic devices.

  8. A Comparison of Land Surface Water Mapping Using the Normalized Difference Water Index from TM, ETM+ and ALI

    OpenAIRE

    Bingyu Sun; Yuanmiao Gui; Hailei Wang; Dongbo Zhou; Feng Ling; Zhiqiang Du; Wenbo Li; Xiaoming Zhang

    2013-01-01

    Remote sensing has more advantages than the traditional methods of land surface water (LSW) mapping because it is a low-cost, reliable information source that is capable of making high-frequency and repeatable observations. The normalized difference water indexes (NDWIs), calculated from various band combinations (green, near-infrared (NIR), or shortwave-infrared (SWIR)), have been successfully applied to LSW mapping. In fact, new NDWIs will become available when Advanced Land Imager (ALI) da...

  9. Neighborhood context and ethnicity differences in body mass index: A multilevel analysis using the NHANES III survey (1988–1994)

    OpenAIRE

    Do, D. Phuong; Dubowitz, Tamara; Bird, Chloe E.; Lurie, Nicole; Escarce, José J.; Finch, Brian K.

    2007-01-01

    A growing body of literature has documented a link between neighborhood context and health outcomes. However, little is known about the relationship between neighborhood context and body mass index (BMI) or whether the association between neighborhood context and BMI differs by ethnicity. This paper investigates several neighborhood characteristics as potential explanatory factors for the variation of BMI across the United States; further, this paper explores to what extent segregation and th...

  10. Advanced Spaceborne Thermal Emission and Reflection Radometer (ASTER Enhanced Vegetation Index (EVI Products from Global Earth Observation (GEO Grid: An Assessment Using Moderate Resolution Imaging Spectroradiometer (MODIS for Synergistic Applications

    Directory of Open Access Journals (Sweden)

    Satoshi Tsuchida

    2012-08-01

    Full Text Available We assessed the compatibility of three Advanced Spaceborne Thermal Emission and Reflection Radometer (ASTER based Enhanced Vegetation Index (EVI products generated in the GEO Grid system to Moderate Resolution Imaging Spectroradiometer (MODIS EVI. The three products were two forms of the two-band EVI with ASTER red and NIR bands but without a blue band and the original, three-band EVI computed with ASTER red and NIR, and MODIS blue reflectances. Our assessment results showed good compatibilities of all the three ASTER EVI products with MODIS EVI, suggesting potential for synergistic applications of multi-resolution EVI.

  11. Vegetation Cover Change in Yosemite National Park (California) Detected using Landsat Satellite Image Analysis

    Science.gov (United States)

    Potter, Christopher

    2015-01-01

    Landsat image analysis over the past 20+ years showed that consistent increases in the satellite normalized difference vegetation index (NDVI) during relatively dry years were confined to large wildfire areas that burned in the late 1980s and 1990s.

  12. Lactic acid fermentation in vegetable juices supplemented with different content of brewer’s yeast autolysate

    OpenAIRE

    Rakin Marica B.; Baras Josip K.; Vukašinovi? Maja S.

    2005-01-01

    The work is concerned with the conditions for lactic acid fermentation in a mixture of beetroot (Beta vulgaris L) juice and carrot (Daucus carota L) juice and different content of brewer’s yeast autolysate with Lactobacillus plantarum A112 and with Lactobacillus acidophilus NCDO 1748.Both cultures showed good biochemical activity in these mixtures. The production of lactic acid has been stimulated using the higher content of brewer’s yeast autolysate. In these mixtures, L. plantarum A112 has ...

  13. Eddy covariance and scintillation measurements of atmospheric exchange processes over different types of vegetation

    OpenAIRE

    Nieveen, J.P.

    1999-01-01

    Introduction and objectivesGood comprehension of the energy and mass cycles and their effect on climate dynamics is crucial to understanding, predicting and anticipating ecological changes due to possible future climate perturbations. Here direct and long-term flux density measurements of greenhouse gases from various ecosystems provide means to supply such fundamental knowledge. For the global water vapour and carbon cycles, however, the interactions between different spatial scales become i...

  14. Attraction of Sphenophorus levis Vaurie adults (Coleoptera: Curculionidae) to vegetal tissues at different conservation levels

    International Nuclear Information System (INIS)

    The occurrence of the sugarcane weevil Sphenophorus levis Vaurie is important in sugarcane in some regions in Brazil. Damage is caused by the larvae as they bore into the nodes and can reach 30 ton/ha/year. Many control alternatives have been attempted, but none were satisfactory, except for the use of toxic baits. Therefore, it is necessary to optimize their efficiency or to propose new techniques. The objective of the current study was to evaluate the attractiveness of adults of S. levis to sugarcane nodes and pineapple peelings in an 'Y' tube olfactometer. The sugarcane internodes were treated with 10% molasses, and tested after different periods of fermentation (24, 48 e 72h), at different times of the day (diurnal and nocturnal) and with both sexes. These tests were carried out in order to correlate the response of S. levis to ethyl acetate and ethanol release as a result of the fermentation process. The release of both compounds was monitored by gas chromatography-mass spectrometry (GC-MS). Our data indicated that sugarcane internodes mixed with 10% molasses fermented for 24h and 48h were the most attractive to S. levis (up to 90%). Pineapple peelings attracted 62.5% of the tested insects. The olfactory response was higher during the day, and no differences were found between the sexes. The production of ethanol in all plant substrates was higher than ethyl acetate, but we could not establish a clear correlation with the insect response to baits. (author)

  15. WATER FROM DIFFERENT SOURCES USED FOR THE IRRIGATION OF VEGETABLES TO BE MARKETED: RESEARCH ON Cryptosporidiumspp., Giardiaspp., AND COLIFORMS IN PARANA, BRAZIL

    OpenAIRE

    Rogerio TIYO; Carla Zangari de SOUZA; NISHI, Letícia; Camila Fernanda BRUSTOLIN; RATTI, Bianca Altrão; Ana Lucia FALAVIGNA GUILHERME

    2015-01-01

    SUMMARY The aim of this work was to compare, from a parasitological ( Cryptosporidiumspp. and Giardia duodenalis), bacteriological (total and thermotolerants coliforms) and physicochemical perspective, water sources used for drinking and irrigation of vegetables intended to be sold for human consumption. From January 2010 to May 2011, samples of different water sources from vegetable producing properties were collected; 100 liters for parasitological analysis, 200 mL for bacteriological analy...

  16. Vegetative development of orchid hybrid in different substratesDesenvolvimento vegetativo de híbrido de orquídea em diferentes substratos

    Directory of Open Access Journals (Sweden)

    Alessandro Garrett Dronk

    2012-12-01

    Full Text Available For commercial production of orchids, it is essential to use a good substrate, and the selection of this material is very important to evaluate aspects of the economic, physical, chemical, biological, and ecological points of view. The aim of this study was to evaluate the development of clones of BLC Nan Chang Silk ‘Olimpic Torch’ on different substrates. The substrates were: T1: tree fern fiber “xaxim” (control, T2: coconut fiber, T3: composted pine bark, T4: plant coal, T5: composted pine bark + coconut fiber (1:1 v/v T6: coconut fiber + plant coal (1:1 v/v, T7: plant coal + composted pine bark (1:1 v/v, T8: plant coal + composted pine bark + coconut fiber ( 1:1:1 v/v/v. The seedlings were grown in pots of polypropylene, kept in a nursery with 80% of brightness. We evaluated 24 months after the start of the experiment: number of pseudobulbs, the lenght of pseudobulbs, height of the plant area, height of the aerial part / lenght of the pseudobulbs and pH and electrical conductivity of the substrate. Based on the parameters of vegetative development it was concluded that all the evaluated substrates can be efficiently used for the cultivation of BLC Nan Chang Silk ‘Olimpic Torch’. A produção de orquídeas é uma atividade em crescente expansão nos mercados nacional e internacional, tornando-se evidente a necessidade de informações que permitam a otimização do seu cultivo. Para a produção comercial de orquídeas, é imprescindível a utilização de um substrato que permita maior crescimento das mudas e, na seleção deste material, é muito importante avaliar aspectos do ponto de vista econômico, físico, químico, biológico e ecológico. O objetivo deste trabalho foi avaliar o desenvolvimento de clones de BLC Nan Chang Silk ‘Olimpic Torch’, obtida do cruzamento entre BLC. Bryce Canyon x BLC. Pamela Hetherington, em diferentes substratos. Os substratos avaliados foram: T1: fibra de xaxim (controle; T2: fibra de coco; T3: casca de pinus compostado; T4: carvão vegetal; T5: casca de pinus compostado + fibra de coco (1:1 v/v; T6: fibra de coco + carvão vegetal (1:1 v/v; T7: carvão vegetal + casca de pinus compostado (1:1 v/v; T8: carvão vegetal + casca de pinus compostado + fibra de coco (1:1:1 v/v/v. As mudas foram cultivadas em vasos de polipropileno, permanecendo em viveiro com 80% de luminosidade. Os parâmetros avaliados 24 meses após o início do experimento foram: número de pseudobulbos, diâmetro médios dos pseudobulbos, altura da parte área da planta, relação altura da parte aérea /comprimento dos pseudobulbos e o pH e a condutividade elétrica dos substratos. Com base nos parâmetros de desenvolvimento vegetativos concluiu-se que todos os substratos avaliados podem ser utilizados eficientemente para o cultivo de BLC Nan Chang Silk ‘Olimpic Torch’.

  17. Junk Food and Body Mass Index

    Medline Plus

    Full Text Available ... mass index. There was no significant difference in consumption of fast food, soft drinks or desserts between overweight and healthy weight individuals. On the other hand, fruit and vegetable consumption did vary significantly between BMI categories. The study ...

  18. Junk Food and Body Mass Index

    Medline Plus

    Full Text Available ... no association between intake of junk food and body mass index. There was no significant difference in consumption of fast food, soft drinks or desserts between overweight and healthy weight individuals. On the other hand, fruit and vegetable ...

  19. THE EFFECT OF DIFFERENT TYPES OF STRAW MULCHES ON WEED-CONTROL IN VEGETABLES CULTIVATION

    OpenAIRE

    Edyta Kosterna

    2014-01-01

    The experiment was carried out in 2010–2012. The effect of different kinds of straw and its dose applied to soil mulching on the amount and fresh mass of weeds and yield level of broccoli and tomato was investigated. The type of straw mulch applied to the soil mulching influenced number and fresh mass of weeds. This effect could be the result of the properties of the mulch (colour, structure, etc.) or the allelopathic effect on the germination and growth of individual weed species. The most e...

  20. Comparison of the vegetation and seed bank on hedge banks of different ages in Brittany, France

    DEFF Research Database (Denmark)

    Gallet, S; Roze, F; Pellissier, Vincent

    2004-01-01

    The composition of the herbaceous cover and the seed bank of old and recent hedge banks in Brittany were studied and compared. Concentration method was used for seed bank samples. Grime's plant strategies were used to explain observed patterns. The analysis of the seed bank of these hedge banks showed that the species richness and diversity differed in relation to the date of construction of the hedge banks. The seed banks of recent hedge banks were richer and more diversified than those of old ...

  1. Evaluation of Effluent Quality Used for Irrigation of Vegetable Production in Different Districts of Potowar, Pakistan

    OpenAIRE

    Tahir Hussain Chattha; Mateen ul Hassan Khan; Muhammad Imran Latif

    2005-01-01

    A study was conducted in different districts of Potowar region to evaluate the quality of sewage for irrigation purposes and heavy metal contents in sewage water. Sewage samples were collected from 25 sewage irrigated farms around Rawalpindi, Attock and Abotabad districts. Electrical conductivity of the samples ranged from 0.55-2.36 dS m-1. Sixty percent of the samples did not pose salinity hazard while forty percent were marginally fit for irrigation. Sodium adsorption ratio ranged from 0.24...

  2. Cognitive Strategy Use as an Index of Developmental Differences in Neural Responses to Feedback

    DEFF Research Database (Denmark)

    Andersen, Lau M.; Visser, Ingmar; Crone, Eveline A.; Koolschijn, P. Cédric; Raijmakers, Maartje E. J.

    2014-01-01

    Developmental differences in dorsolateral prefrontal cortex (DLPFC), anterior cingulate cortex (ACC) and superior parietal cortex (SPC) activation are associated with differences in how children, adolescents, and adults learn from performance feedback in rule-learning tasks (Crone, Zanolie, Leije...

  3. Effects of different vegetation on temperature in an urban building environment. Micro-scale numerical experiments

    Energy Technology Data Exchange (ETDEWEB)

    Gross, Guenter [Hannover Univ. (Germany). Inst. fuer Meteorologie und Klimatologie

    2012-08-15

    A three-dimensional micro-scale model is used to study the effects of various greenery on temperature in a built-up environment. Green design elements like roofs and facades, lawns in courtyards and single trees are studied individually as well as in various combinations. Measures for comparison are temperatures at 2 m height and mean temperatures for the urban atmosphere up to the building height. Different types of greenery can reduce local temperatures up to 15 K during specific daytime hours. However, this extraordinary effect is restricted to a short time and especially to the direct surroundings, while an impact over larger distances is small. Roof and facade greenery have hardly any influence on temperature at the 2 m level but reduce daytime heating of the urban atmosphere to a minor degree, while the relevance of trees is more or less limited to the shadow effect. A significant decrease in urban temperatures can be achieved only with a large number of very different individual green elements. The largest effect on the urban atmosphere was simulated for a change in albedo resulting in a temperature decrease of some degrees around noon. (orig.)

  4. Temporal variation of aqueous-extractable Ca, Mg and K in acidified forest mountainous soils under different vegetation cover

    Science.gov (United States)

    Tejnecky, V.; Bradová, M.; Boruvka, L.; Vasat, R.; Nemecek, K.; Ash, C.; Sebek, O.; Rejzek, J.; Drabek, O.

    2012-12-01

    Acidification of forest soils is a natural degradation process which can be significantly enhanced by anthropogenic activities. Inputs of basic cations (BC - Ca, Mg and K) via precipitation, litter and soil organic matter decomposition and also via inter-soil weathering may partially mitigate the consequences of this degradation process. The aim of this study is to assess the temporal variation of aqueous-extractable Ca, Mg and K in acidified forest mountainous soils under different vegetation cover. The Jizera Mountains region (Czech Republic, northern Bohemia) was chosen as a representative soil mountainous ecosystem strongly affected by acidification. Soil and precipitation samples were collected at monthly basis from April till October/ November during the years 2009-2011. Study spots were delimited under two contrasting vegetation covers - beech and spruce monoculture. Prevailing soil types were classified as Alumic Cambisols under beech and Entic Podzols under spruce stands (according to FAO classification). Soil samples were collected from surface fermentation (F) and humified (H) organic horizons and subsurface B horizons (cambic or spodic). The collected soil samples were analyzed immediately under laboratory condition in a "fresh" state. Unsieved fresh samples were extracted by deionised water. The content of main elements (Ca, Mg, K, Al and Fe) was determined by ICP-OES. The content of major anions (SO42-, NO3-, Cl- and F-) was determined by ion-exchange chromatography (IC). Content of major anions and main elements were determined in the precipitation samples (throughfall, stemflow and bulk) as well. Besides computing the basic statistical parameters (mean, median, variance, maximum, minimum, etc.) we also employed other statistical methods such as T-test and ANOVA to assess the differences between beech and spruce vegetation spots. To carry out the temporal variability in the data we used the time series analysis and short-term forecasting by Holt-Winters exponential smoothing and ARIMA models. Our results clearly exhibit differences in the horizontal and spatial distribution of BC. The influences of the study spot, i.e. the influence of stand factors e.g. vegetation covers on BC distribution are well pronounced. The highest amounts of aqueous extractable BC were identified in the F and H organic horizons. The contents of Ca and Mg were significantly higher under beech cover than under spruce cover. The influence of seasonality on BC content and distribution was the strongest in the upper organic horizons. The annual changes are less pronounced in inner mineral B horizons. We have observed a significant influence of the snow melting period - after this event the content of BC was the lowest. In contrast, the BC content rises during the summer period - the time of high biological activity and accelerated organic matter decomposition. This period is again followed by a BC content decrease during the fall period - the time of gradually decreasing biological activity and high precipitation. Generally, we can conclude that the seasonal variations are higher than annual and spatial for both sites.

  5. Avaliação do ruído através do SPBI (Statistical Pass-By Index) em diferentes pavimentos / Noise evaluation using the SPBI (Statistical Pass-By Index) for different pavements

    Scientific Electronic Library Online (English)

    Luciano Pivoto, Specht; Sérgio C., Callai; Oleg A., Khatchatourian; Raquel, Kohler.

    2009-12-01

    Full Text Available O transporte rodoviário causa grande impacto no meio ambiente, tanto pelo grande consumo de energia quanto pela infra-estrutura física necessária a sua operação. A emissão de gases e os ruídos causados pelo tráfego causam danos irreversíveis ao meio ambiente e têm sido alvo de inúmeros estudos e pes [...] quisas. Sabe-se que o atrito pneu/pavimento e as propriedades acústicas dos revestimentos influenciam de sobremaneira a geração e a propagação do ruído. Essa pesquisa tem como objetivo avaliar o ruído causado pelo tráfego de veículos em quatro diferentes pavimentos implantados em diferentes rodovias através do SPBI (Statistical Pass-By Index). A metodologia adotada seguiu as prescrições da norma ISO 11819-1, a qual determina que um decibelímetro seja instalado na lateral da via para medir o ruído máximo causado pela passagem de um veículo. O revestimento em CBUQ foi o pavimento cujas maiores medidas foram observadas (86,84dBA) seguido do CCP (83,28dBA), do TSD (83,26dBA) do MICRO (81,14dBA) e da CPA (81,03dBA). Os resultados indicam que a escolha adequada do revestimento pode atenuar de maneira expressiva o ruído causado pelo tráfego rodoviário. Abstract in english Highway transportation causes immense environmental impacts, as much by the enormous use of energy as for the physical infrastructure necessary for its operation. The gas emission and traffic noise cause irreversible damages to the environment and this has been the objective of a lot of studies and [...] researches. It is known that the contact between tire and pavement surface and the acoustic properties of the coverings influence the noise’s generation and propagation. This research aims to evaluate the noise caused by the traffic of vehicles in four different pavements through SPBI (Statistical Pass-By Index). The methodology followed the prescriptions of the norm ISO 11819-1; the decibelimeter is installed in the road side and it records the maximum noise caused by each vehicle. HMA presents higher noise measurement (86,84dBA) followed by PCC (83,28dBA), ST (83,26dBA) MICRO (81,14dBA) and PC (81,03dBA). The results indicate that correct pavement selection can reduce, in an expressive way, the noise caused by road traffic.

  6. Avaliação do ruído através do SPBI (Statistical Pass-By Index em diferentes pavimentos Noise evaluation using the SPBI (Statistical Pass-By Index for different pavements

    Directory of Open Access Journals (Sweden)

    Luciano Pivoto Specht

    2009-12-01

    Full Text Available O transporte rodoviário causa grande impacto no meio ambiente, tanto pelo grande consumo de energia quanto pela infra-estrutura física necessária a sua operação. A emissão de gases e os ruídos causados pelo tráfego causam danos irreversíveis ao meio ambiente e têm sido alvo de inúmeros estudos e pesquisas. Sabe-se que o atrito pneu/pavimento e as propriedades acústicas dos revestimentos influenciam de sobremaneira a geração e a propagação do ruído. Essa pesquisa tem como objetivo avaliar o ruído causado pelo tráfego de veículos em quatro diferentes pavimentos implantados em diferentes rodovias através do SPBI (Statistical Pass-By Index. A metodologia adotada seguiu as prescrições da norma ISO 11819-1, a qual determina que um decibelímetro seja instalado na lateral da via para medir o ruído máximo causado pela passagem de um veículo. O revestimento em CBUQ foi o pavimento cujas maiores medidas foram observadas (86,84dBA seguido do CCP (83,28dBA, do TSD (83,26dBA do MICRO (81,14dBA e da CPA (81,03dBA. Os resultados indicam que a escolha adequada do revestimento pode atenuar de maneira expressiva o ruído causado pelo tráfego rodoviário.Highway transportation causes immense environmental impacts, as much by the enormous use of energy as for the physical infrastructure necessary for its operation. The gas emission and traffic noise cause irreversible damages to the environment and this has been the objective of a lot of studies and researches. It is known that the contact between tire and pavement surface and the acoustic properties of the coverings influence the noise’s generation and propagation. This research aims to evaluate the noise caused by the traffic of vehicles in four different pavements through SPBI (Statistical Pass-By Index. The methodology followed the prescriptions of the norm ISO 11819-1; the decibelimeter is installed in the road side and it rec