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Investigation of Vegetation Dynamics using Long-Term NormalizedDifference Vegetation Index Time-Series  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Abstract: Problem statement: The Normalized Difference Vegetation Index (NDVI) is the most extensively used satellite-derived index of vegetation health and density. Since climate is one of the most important factors affecting vegetation condition, satellite-derived vegetation indexes have been often used to evaluate climatic and environmental changes at regional and global scale. The proposed study attempted to investigate the temporal vegetation dynamics in the whole Africa using historical...

Perez, Francesca; Boccardo, Piero; Bellone, Tamara

2009-01-01

2

Investigation of Vegetation Dynamics using Long-Term Normalized Difference Vegetation Index Time-Series  

Directory of Open Access Journals (Sweden)

Full Text Available Problem statement: The Normalized Difference Vegetation Index (NDVI is the most extensively used satellite-derived index of vegetation health and density. Since climate is one of the most important factors affecting vegetation condition, satellite-derived vegetation indexes have been often used to evaluate climatic and environmental changes at regional and global scale. The proposed study attempted to investigate the temporal vegetation dynamics in the whole Africa using historical NDVI time-series. Approach: For this aim, 15 day maximum value NDVI composites at 8 km spatial resolution produced from the NASA Global Inventory Mapping and Monitoring System (GIMMS had been used. They were derived from data collected daily by NOAA AVHRR satellites. The AVHRR NDVI GIMMS dataset was freely available and gives global coverage over an extensive time period. First of all, the selected NDVI base data had been geometrically pre-processed and organized into a historical database implemented in order to grant their spatial integration. Starting from this archive, monthly and yearly NDVI historical time-series, extended from 1982-2006, had been then developed and analysed on a pixel basis. Several routines hade been developed in IDL (Interactive Data Language programming tool with the purpose of applying suitable statistical analysis techniques to the historical information in the database in order to identify the long-term trend components of generated NDVI time-series and extract vegetation dynamics. Specific tests had been then considered in order to define the validity of results. Results: The existence of clear regional trends of NDVI, both decreasing and increasing had been showed, which helped to highlight areas subject, respectively to reduction or increase in vegetation greenness. Conclusion: As the relationship between the NDVI and vegetation productivity was well established, these estimated long-term trend components may be also, with much more caution, related to historical and ongoing land degradation or improvement processes.

Tamara Bellone

2009-01-01

3

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

Directory of Open Access Journals (Sweden)

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.

Gabriela Camargos Lima

2013-08-01

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Sensitivity of the Enhanced Vegetation Index (EVI) and Normalized Difference Vegetation Index (NDVI) to Topographic Effects: A Case Study in High-density Cypress Forest  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Vegetation indices play an important role in monitoring variations in vegetation.The Enhanced Vegetation Index (EVI) proposed by the MODIS Land Discipline Groupand the Normalized Difference Vegetation Index (NDVI) are both global-based vegetationindices aimed at providing consistent spatial and temporal information regarding globalvegetation. However, many environmental factors such as atmospheric conditions and soilbackground may produce errors in these indices. The topographic effect is ano...

Bunkei Matsushita; Wei Yang; Jin Chen; Yuyichi Onda; Guoyu Qiu

2007-01-01

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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.

2010-01-01

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Elk Distributions Relative to Spring Normalized Difference Vegetation Index Values  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 activ...

Smallidge, Samuel T.; Baker, Terrell T.; Dawn VanLeeuwen; Gould, William R.; Thompson, Bruce C.

2010-01-01

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Le Maire, G.; Franc?ois, C.; Soudani, Kamel; Davi, H.; Le Dantec, V.; Saugier, Bernard; Dufrene, E.

2006-01-01

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A normalized difference vegetation index (NDVI) time-series of idle agriculture lands: A preliminary study  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, the NDVI time-series collected from the study area between year 2003 and 2005 of all land cover types are plotted and compared. The study area is the agricultural zones in Banphai District, Khonkean, Thailand. The LANDSAT satellite images of different dates were first transformed into a time series of Normalized Difference Vegetation Index (NDVI) images before the investigation. It can be visually observed that the NDVI time series of the Idle Agriculture Land (IAL) has the NDV...

Vaiphasa, C.; Piamduaytham, S.; Vaiphasa, T.; Skidmore, A. K.

2011-01-01

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A Normalized Difference Vegetation Index (NDVI) Time-Series of Idle Agriculture Lands: A Preliminary Study  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, the NDVI time-series collected from the study area between year 2003 and 2005 of all land cover types are plotted and compared. The study area is the agricultural zones in Banphai District, Khonkean, Thailand. The LANDSAT satellite images of different dates were first transformed into a time series of Normalized Difference Vegetation Index (NDVI) images before the investigation. It can be visually observed that the NDVI time series of the Idle Agriculture Land (IAL) has the NDV...

Chaichoke Vaiphasa; Supawee Piamduaytham; Tanasak Vaiphasa; Skidmore, Andrew K.

2011-01-01

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Integrated NDVI images for Niger 1986-1987. [Normalized Difference Vegetation Index  

Science.gov (United States)

Two NOAA AVHRR images are presented which provide a comparison of the geographic distribution of an integration of the normalized difference vegetation index (NDVI) for the Sahel zone in Niger for the growing seasons of 1986 and 1987. The production of the images and the application of the images for resource management are discussed. Daily large area coverage with a spatial resolution of 1.1 km at nadir were transformed to the NDVI and geographically registered to produce the images.

Harrington, John A., Jr.; Wylie, Bruce K.; Tucker, Compton J.

1988-01-01

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 a...

Ronald Eastman, J.; Florencia Sangermano; Machado, Elia A.; John Rogan; Assaf Anyamba

2013-01-01

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Atmospheric effects on the NDVI - Strategies for its removal. [Normalized Difference Vegetation Index  

Science.gov (United States)

The compositing technique used to derive global vegetation index (NDVI) from the NOAA AVHRR radiances reduces the residual effect of water vapor and aerosol on the NDVI. The reduction in the atmospheric effect is shown using a comprehensive measured data set for desert conditions, and a simulation for grass with continental aerosol. A statistical analaysis of the probability of occurrence of aerosol optical thickness and precipitable water vapor measured in different climatic regimes is used for this simulation. It is concluded that for a long compositing period (e.g., 27 days), the residual aerosol optical thickness and precipitable water vapor are usually too small to be corrected. For a 9-day compositing, the residual average aerosol effect may be about twice the correction uncertainty. For Landsat TM or Earth Observing System Moderate Resolution Imaging Spectrometer (EOS-MODIS) data, the newly defined atmospherically resistant vegetation index (ARVI) is more promising than possible direct atmospheric correction schemes, except for heavy desert dust conditions.

Kaufman, Y. J.; Tanre, D.; Holben, B. N.; Markham, B.; Gitelson, A.

1992-01-01

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

DEFF Research Database (Denmark)

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 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 LAIâ??normalized difference vegetation index (NDVI) relationships for typical C. tetragona tundras in the subarctic (Sweden) and High Arctic (Greenland and Svalbard). Leaves of C. tetragona are 2â??6 mm long and closely appressed to their stems forming parallelepiped shoots. We determined the LAI of C. tetragona by measuring the area of the leaves while still attached to the stem, then doubling the resulting one-sided area. TFN was determined from 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, the LAI of C. tetragona tundra ranged from 0.4 to 1.1 m2 mâ??2 and TFN from 1.4 to 1.7 g N mâ??2.

Campioli, M; Street, LE

2009-01-01

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Interannual growth dynamics of vegetation in the Kuparuk River watershed, Alaska based on the Normalized Difference Vegetation Index  

Science.gov (United States)

Interannual above-ground production patterns are characterized for three tundra ecosystems in the Kuparuk River watershed of Alaska using NOAA-AVHRR Normalized Difference Vegetation Index (NDVI) data. NDVI values integrated over each growing season (SINDVI) were used to represent seasonal production patterns between 1989 and 1996. Spatial differences in ecosystem production were expected to follow north-south climatic and soil gradients, while interannual differences in production were expected to vary with variations in seasonal precipitation and temperature. It was hypothesized that the increased vegetation growth in high latitudes between 1981 and 1991 previously reported would continue through the period of investigation for the study watershed. Zonal differences in vegetation production were confirmed but interannual variations did not covary with seasonal precipitation or temperature totals. A sharp reduction in the SINDVI in 1992 followed by a consistent increase up to 1996 led to a further hypothesis that the interannual variations in SINDVI were associated with variations in stratospheric optical depth. Using published stratospheric optical depth values derived from the SAGE and SAGE-II satellites, it is demonstrated that variations in these depths are likely the primary cause of SINDVI interannual variability.

Hope, A. S.; Boynton, W. L.; Stow, D. A.; Douglas, D. C.

2003-01-01

15

Fisher-Shannon information plane analysis of SPOT/VEGETATION Normalized Difference Vegetation Index (NDVI) time series to characterize vegetation recovery after fire disturbance  

Science.gov (United States)

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.

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

2014-02-01

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Evaluating the difference between the normalized difference vegetation index and net primary productivity as the indicators of vegetation vigor assessment at landscape scale.  

Science.gov (United States)

Both the net primary productivity (NPP) and the normalized difference vegetation index (NDVI) are commonly used as indicators to characterize vegetation vigor, and NDVI has been used as a surrogate estimator of NPP in some cases. To evaluate the reliability of such surrogation, here we examined the quantitative difference between NPP and NDVI in their outcomes of vegetation vigor assessment at a landscape scale. Using Landsat ETM+ data and a process model, the Boreal Ecosystem Productivity Simulator, NPP distribution was mapped at a resolution of 90 m, and total NDVI during the growing season was calculated in Heihe River Basin, Northwest China in 2002. The results from a comparison between the NPP and NDVI classification maps show that there existed a substantial difference in terms of both area and spatial distribution between the assessment outcomes of these two indicators, despite that they are strongly correlated. The degree of difference can be influenced by assessment schemes, as well as the type of vegetation and ecozone. Overall, NDVI is not a good surrogate of NPP as the indicators of vegetation vigor assessment in the study area. Nonetheless, NDVI could serve as a fairish surrogate indicator under the condition that the target region has low vegetation cover and the assessment has relatively coarse classification schemes (i.e., the class number is small). It is suggested that the use of NPP and NDVI should be carefully selected in landscape assessment. Their differences need to be further evaluated across geographic areas and biomes. PMID:21625921

Xu, Chi; Li, Yutong; Hu, Jian; Yang, Xuejiao; Sheng, Sheng; Liu, Maosong

2012-03-01

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Analysis of regional-scale vegetation dynamics of Mexico using stratified AVHRR NDVI data. [Normalized Difference Vegetaion Index  

Science.gov (United States)

Previous studies have shown that a good relationship exists between AVHRR Normalized Difference Vegetation Index (NDVI) measurements, and both regional-scale patterns of vegetation seasonality and productivity. Most of these studies used known samples of vegetation types. An alternative approach, and the objective was to examine the above relationships by analyzing one year of AVHRR NDVI data that was stratified using a small-scale vegetation map of Mexico. The results show that there is a good relationship between AVHRR NDVI measurements and regional-scale vegetation dynamics of Mexico.

Turcotte, Kevin M.; Kramber, William J.; Venugopal, Gopalan; Lulla, Kamlesh

1989-01-01

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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)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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.

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

19

Experience with Low-Cost LED Spectral Sensors for Normalized Difference Vegetation Index (NDVI)  

Science.gov (United States)

Continuous monitoring of canopy architecture and greenness is an economic challenge to researchers doing plot studies. Important questions could be answered by inexpensive but robust spectral sensors. We show here how light emitting diodes (LEDs) can be used as low-cost, narrow band spectral sensors. The wavelengths they sense are not exactly those for emission, but the two are closely related. We made 22 sensors, each having a red and a near infrared LED mounted behind a Teflon° diffuser. We used a shunt resistor across each LED to limit its output to around 20 mv. This measurement of short circuit current produces an output which is linear with irradiance and minimizes temperature sensitivity of the sensor. The output of the sensors was measured with Campbell Scientific CR1000 loggers. We computed Normalized Difference Vegetation Index (NDVI) using one up-facing and 10 down-facing sensors at each of two locations in the Great Basin Experimental Range on the Wasatch Plateau in Utah. These sensors allowed continuous monitoring of leaf area index and canopy green biomass over the growing season with a spatial resolution which would have been cost-prohibitive with conventional sensors. All sensors worked well during the season in which they were installed, but were destroyed by heavy snows in the 2010-2011 winter. More robust, but still inexpensive versions have been built and installed for the 2011-2012 season to try to monitor during snow melt and early growth periods.

Campbell, C. S.; Gill, R. A.; Campbell, G.; Cobos, D.

2011-12-01

20

A Normalized Difference Vegetation Index (NDVI Time-Series of Idle Agriculture Lands: A Preliminary Study  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper, the NDVI time-series collected from the study area between year 2003 and 2005 of all land cover types are plotted and compared. The study area is the agricultural zones in Banphai District, Khonkean, Thailand. The LANDSAT satellite images of different dates were first transformed into a time series of Normalized Difference Vegetation Index (NDVI images before the investigation. It can be visually observed that the NDVI time series of the Idle Agriculture Land (IAL has the NDVI values closed to zero. In other words, the trend of the NDVI values remains, approximately, unchanged about the zero level for the whole period of the study time. In contrast, the non-idle areas hold a higher level of the NDVI variation. The NDVI values above 0.5 can be found in these non-idle areas during the growing seasons. Thus, it can be hypothesized that the NDVI time-series of the different land cover types can be used for IAL classification. This outcome is a prerequisite to the follow-up study of the NDVI pattern classification that will be done in the near future.

Andrew K Skidmore

2011-01-01

 
 
 
 
21

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

Science.gov (United States)

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.

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

22

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

Directory of Open Access Journals (Sweden)

Full Text Available 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.

A. McNally

2013-06-01

23

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

Directory of Open Access Journals (Sweden)

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.

Howard Viator

2012-06-01

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Estimating sugarcane yield potential using an in-season determination of normalized difference vegetative index.  

Science.gov (United States)

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 (r(2) 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 (r(2) 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. PMID:22969359

Lofton, Josh; Tubana, Brenda S; Kanke, Yumiko; Teboh, Jasper; Viator, Howard; Dalen, Marilyn

2012-01-01

25

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

Directory of Open Access Journals (Sweden)

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.

Assaf Anyamba

2013-09-01

26

Use of Normalized Difference Vegetation Index (NDVI) habitat models to predict breeding birds on the San Pedro River, Arizona  

Science.gov (United States)

Successful management practices of avian populations depend on understanding relationships between birds and their habitat, especially in rare habitats, such as riparian areas of the desert Southwest. Remote-sensing technology has become popular in habitat modeling, but most of these models focus on single species, leaving their applicability to understanding broader community structure and function largely untested. We investigated the usefulness of two Normalized Difference Vegetation Index (NDVI) habitat models to model avian abundance and species richness on the upper San Pedro River in southeastern Arizona. Although NDVI was positively correlated with our bird metrics, the amount of explained variation was low. We then investigated the addition of vegetation metrics and other remote-sensing metrics to improve our models. Although both vegetation metrics and remotely sensed metrics increased the power of our models, the overall explained variation was still low, suggesting that general avian community structure may be too complex for NDVI models.

McFarland, Tiffany Marie; van Riper, Charles, III

2013-01-01

27

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)

2011-06-10

28

Method for Tealeaves Quality Estimation Through Measurements of Degree of Polazation, Leaf Area Index, Photosynthesis Available Radiance and Normalized Difference Vegetation Index for Characterization of Tealeaves  

Directory of Open Access Journals (Sweden)

Full Text Available Method for tealeaves quality estimation through measurements of Degree of Polarization: DP, Leaf Area Index: LAI, Photosynthesis Available Radiance: PAR and Normalized Difference Vegetation Index: NDVI for characterization of tealeaves is proposed. The method allows estimations of PAR, NDVI, Grow Index: GI by using measured Degree of Polarization: DP of tealeaves. Through experiments at the tea farm areas, it is found that the proposed method is validated. Also, the method is validated through Monte Carlo Ray Tracing: MCRT simulations for discrimination between prolate and oblate shapes of tealeaves. In accordance with growing tealeaves, prolate shape of tealeaves changes their shape to oblate shape. Therefore, growing stage can be estimated with DP measurements.

Kohei Arai

2013-11-01

29

Response of normalized difference vegetation index in main vegetation types to climate change and their variations in different time scales along a North-South Transect of Eastern China  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Aims Climate change characterized by global warming has posed a great threat to terrestrial ecosystems and sustainable development of human society. Our objective was to examine the response of major vegetation types to climate change.Methods We used the biweekly dataset of the National Oceanographic and Atmospheric Administration/Advanced Very High Resolution Radiometer (NOAA/AVHRR) normalized difference vegetation index (NDVI) and climatic data from 752 standard stations in China for 1982?...

2011-01-01

30

The Asian Dust Aerosol Model 2 (ADAM2) with the use of Normalized Difference Vegetation Index (NDVI) obtained from the Spot4/vegetation data  

Science.gov (United States)

The operational Asian Dust Aerosol Model (ADAM)1 in Korea Meteorological Administration has been modified to the ADAM2 model to be used as an operational forecasting model all year round not only in Korea but also in the whole Asian domain (70-160°E and 5-60°N) using the routinely available World Meteorological Organization (WMO) surface reporting data and the Spot/vegetation Normalized Difference Vegetation Index (NDVI) data for the period of 9 years from 1998 to 2006. The 3-hourly reporting WMO surface data in the Asian domain have been used to re-delineate the Asian dust source region and to determine the temporal variation of the threshold wind speed for the dust rise. The dust emission reduction factor due to vegetation in different surface soil-type regions (Gobi, sand, loess, and mixed soil) has been determined with the use of NDVI data. It is found that the threshold wind speed for the dust rise varies significantly with time (minimum in summer and maximum in winter) and surface soil types with the highest threshold wind speed of 8.0 m s-1 in the Gobi region and the lowest value of 6.0 m s-1 in the loess region. The statistical analysis of the spot/vegetation NDVI data enables to determine the emission reduction factor due to vegetation with the free NDVI value that is the NDVI value without the effect of vegetation and the upper limit value of NDVI for the dust rise in different soil-type regions. The modified ADAM2 model has been implemented to simulate two Asian dust events observed in Korea for the periods from 31 March to 2 April 2007 (a spring dust event) and from 29 to 31 December 2007 (a winter dust event) when the observed PM10 concentration at some monitoring sites in the source region exceeds 9,000 ?g m-3. It is found that ADAM2 model successfully simulates the observed high dust concentrations of more than 8,000 ?g m-3 in the dust source region and 600 ?g m-3 in the downstream region of Korea. This suggests that ADAM2 has a great potential for the use of an operational Asian dust forecast model in the Asian domain.

Park, Soon-Ung; Choe, Anna; Lee, Eun-Hee; Park, Moon-Soo; Song, Xingzhuo

2010-07-01

31

Classifying cropping area of middle Heihe River Basin in China using multitemporal Normalized Difference Vegetation Index data  

Science.gov (United States)

Accurate information regarding the structure of crops is critical for the improvement and optimization of land surface models. Multitemporal remote sensing imagery is more effective to determine the crop structure than the single-temporal images because they contain phenological information. Crop structure was extracted based on time series of moderate-resolution imaging spectroradiometer (MODIS) data in the middle Heihe River Basin. A time series of Normalized Difference Vegetation Index (NDVI) data with a 3-day temporal resolution was composed based on daily MODIS reflectance products (MOD 09) from January to December 2011. A total of 120 scenes of composited imagery were integrated into an image data cube of NDVI time series, which was used to extract crop structure for the study area. The spectral curves of corn, wheat, rape, vegetables, and other crops are based on both in situ measurements and visual interpretation. The major crop types were classified by using the adaptive boosting (Adaboost) and support vector machine (SVM) algorithms. The results show that the classification accuracy of Adaboost and SVM was 86.01% and 70.28%, respectively, with Kappa coefficients of 0.8351 and 0.6438, respectively. Summarizing the classification methods used in this study effectively characterize the spatial distribution of the main crops.

Han, Huibang; Ma, Mingguo; Wang, Xufeng; Ma, Shoucun

2014-01-01

32

Rainfall Variability and Its Impact on Normalized Difference Vegetation Index in Arid and Semi-Arid Lands of Kenya  

Directory of Open Access Journals (Sweden)

Full Text Available Agriculture in arid and semi-arid lands of Kenya is depends on seasonal characteristics of rainfall. This study seeks to distinguish components of regional climate variability, especially El Niño Southern Oscillation events and their impact on the growing season normalized difference vegetation index (NDVI. Datasets used were: 1 rainfall (1961-2003 and 2 NDVI (1981-2003. Results indicate that climate variability is persistent in the arid and semi-arid lands of Kenya and continues to affect vegetation condition and consequently crop production. Correlation calculations between seasonal NDVI and rainfall shows that the October-December (OND growing season is more reliable than March-May (MAM season. Results show that observed biomass trends are not solely explained by rainfall variability but also changes in land cover and land use. Results show that El Niño and La Niña events in southeast Kenya vary in magnitude, both in time and space as is their impact on vegetation; and that variation in El Niño intensity is higher than during La Niña events. It is suggested that farmers should be encouraged to increase use of farm input in their agricultural enterprises during the OND season; particularly when above normal rains are forecast. The close relationship between rainfall and NDVI yield ground for improvement in the prediction of local level rainfall. Effective dissemination of this information to stakeholders will go along way to ameliorate the suffering of many households and enable government to plan ahead of a worse season. This would greatly reduce the vulnerability of livelihoods to climate related disasters by improving their management.

C. A. Shisanya

2011-02-01

33

Spatial and Temporal Variation of Normalized Difference Vegetation Index (NDVI and Rainfall in the North East Arid Zone of Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available This study examines the spatial and temporal variation of onset and cessation of rainfall and greenness in the North East Arid Zone of Nigeria. Onset and cessation of greenness dates were determined from mean monthly time series of Normalized Difference Vegetation Index (NDVI using Advance Very High Resolution Radiometer (AVHRR data for five meteorological stations in the zone for a period of nineteen years (1981-1999. Lowest growing days of six weeks were observed in Nguru (12.53°N, 10.28°E, alt.343 m, Potiskum (11.42°N, 11.02°E, alt.415 m and Maiduguri (11.51°N, 13.05°E, alt. 354 m, while Yola (12.28°N, 9.14°E, alt.174 m and Bauchi (10.17°N, 9.49°E, alt.609 m have growing days of 15 and 16 weeks respectively. Highest rate of greenness of 0.18/month was observed inMaiduguriwhile the lowest rate of green-up of 0.07/month was observed in Bauchi. Similarly, highest rate of senescence (0.08/month was observed in Bauchi while lowest rate of senescence (0.04/month was observed in Nguru.

Christiana F. Olusegun

2013-08-01

34

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.

2013-06-10

35

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

Science.gov (United States)

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.

Ahmed, A.; Akhtar, A.; Khalid, B.; Shamim, A.

2013-06-01

36

The vegetative index number and crop identification  

Science.gov (United States)

A vegetative index number of numerical value was calculated from the digital values of the LANDSAT system to provide some measure of green growing vegetation. The usefulness of the green numbers for schemes in crop identification and acreage estimation is investigated and the Ashburn vegetation index (AVI) is compared with the Kauth-Thomas vegetation index (KVI) for crop identification schemes. Results of wheat acreage estimation using LACIE Procedure 1 and the AVI for eight sample segments are given. Tables show comparisons between the AVI and the KVI as well as visual results of the AVI.

Ashburn, P. (principal investigator)

1979-01-01

37

Test of Multi-spectral Vegetation Index for Floating and Canopy-forming Submerged Vegetation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Remote sensing of terrestrial vegetation has been successful thanks to the unique spectral characteristics of green vegetation, low reflectance in red and high reflectance in Near-InfraRed (NIR). These spectral characteristics were used to develop vegetation indices, including Normalized Difference Vegetation Index (NDVI). However, the NIR absorption by water and light scattering from suspended particles reduces the practical application of such indices in aquatic vegetation studies, especial...

Hyun Jung Cho; Philemon Kirui; Harene Natarajan

2008-01-01

38

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

Directory of Open Access Journals (Sweden)

Full Text Available 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 normalized difference vegetation index (GIMMS NDVI3g. Pearson’s correlation and multiple linear stepwise regression analyses were applied to quantify the NDVI interannual variability driven by climate anomalies, and to evaluate the effects of potential interference (snow, aerosols and clouds on the NDVI signal. We found ecologically plausible strong controls on NDVI variability by antecedent precipitation and current monthly temperature with distinct spatial patterns. Precipitation correlations were strongest for temperate to tropical water limited herbaceous systems where in some regions and seasons > 40% of the NDVI variance could be explained by precipitation anomalies. Temperature correlations were strongest in northern mid- to high-latitudes in the spring and early summer where up to 70% of the NDVI variance was explained by temperature anomalies. We find that, in western and central North America, winter-spring precipitation determines early summer growth while more recent precipitation controls NDVI variability in late summer. In contrast, current or prior wet season precipitation anomalies were correlated with all months of NDVI in sub-tropical herbaceous vegetation. Snow, aerosols and clouds as well as unexplained phenomena still account for part of the NDVI variance despite corrections. Nevertheless, this study demonstrates that GIMMS NDVI3g represents real responses of vegetation to climate variability that are useful for global models.

Alvaro Ivanoff

2013-08-01

39

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

Science.gov (United States)

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

Fang, Shi-bo; Zhang, Xin-shi

2011-03-01

40

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2013-01-01

 
 
 
 
41

A Wetness Index Using Terrain-Corrected Surface Temperature and Normalized Difference Vegetation Index Derived from Standard MODIS Products: An Evaluation of Its Use in a Humid Forest-Dominated Region of Eastern Canada  

Directory of Open Access Journals (Sweden)

Full Text Available In this paper we develop a method to estimate land-surface water content in amostly forest-dominated (humid and topographically-varied region of eastern Canada. Theapproach is centered on a temperature-vegetation wetness index (TVWI that uses standard 8-day MODIS-based image composites of land surface temperature (TS and surface reflectanceas primary input. In an attempt to improve estimates of TVWI in high elevation areas, terrain-induced variations in TS are removed by applying grid, digital elevation model-basedcalculations of vertical atmospheric pressure to calculations of surface potential temperature(θS. Here, θS corrects TS to the temperature value to what it would be at mean sea level (i.e.,~101.3 kPa in a neutral atmosphere. The vegetation component of the TVWI uses 8-daycomposites of surface reflectance in the calculation of normalized difference vegetation index(NDVI values. TVWI and corresponding wet and dry edges are based on an interpretation ofscatterplots generated by plotting θS as a function of NDVI. A comparison of spatially-averaged field measurements of volumetric soil water content (VSWC and TVWI for the 2003-2005 period revealed that variation with time to both was similar in magnitudes. Growing season, point mean measurements of VSWC and TVWI were 31.0% and 28.8% for 2003, 28.6% and 29.4% for 2004, and 40.0% and 38.4% for 2005, respectively. An evaluation of the long-term spatial distribution of land-surface wetness generated with the new θS-NDVI function and a process-based model of soil water content showed a strong relationship (i.e., r2 = 95.7%.

Roger M. Cox

2007-10-01

42

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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-temp...

Ainong Li; Wei Deng; Shunlin Liang; Chengquan Huang

2010-01-01

43

Série temporal de índice de vegetação sobre diferentes tipologias vegetais no Rio Grande do Sul / Time series of vegetation index for different vegetation types in Rio Grande do Sul  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Com este trabalho objetivou-se identificar a dinâmica fenológica das principais tipologias vegetais do Rio Grande do Sul, para o período de 2000 a 2010, utilizando-se dados de Enhanced Vegetation Index, através da transformada de ondaleta. A identificação da fenologia em ciclos ou padrões sazonais e [...] m séries temporais de índices de vegetação, obtidos por sensores orbitais, permite a observação de anomalias e os efeitos de mudanças climáticas ou ambientais. Um perfil temporal do Enhanced Vegetation Index foi construído para o Rio Grande do Sul e retiradas amostras para quatro tipologias vegetais: campo nativo, floresta ombrófila mista, cultivo de soja e de arroz. Essas amostras foram submetidas à transformada de ondaleta, que permitiu a decomposição da série e apresentação dos dados em relação ao tempo e frequência com que os eventos fenológicos ocorreram. Os dados apresentaram regularidade na dinâmica das tipologias vegetais testadas, com ciclos anuais de maior vigor e crescimento vegetal nas estações de primavera e verão e menor no outono e inverno. Abstract in english The objective of this study was the identification of the phenology dynamics of the main types of vegetation of Rio Grande do Sul state, for the period from 2000 to 2010, using Enhanced Vegetation Index data through the wavelet transform. The identification of cycles or seasonal patterns in time ser [...] ies of vegetation indices obtained by orbital sensors allows the observation of anomalies and effects of climate and environmental change. A temporal profile of Enhanced Vegetation Index was built for the Rio Grande do Sul region, where samples of the four main plant typologies were selected: native grassland, mixed ombrophilous forest, soybean and rice crop. These samples were submitted to the wavelet transform, which allowed the decomposition of the series and presentation of data in relation to time and frequency with which the phenological events have occurred. The data showed regularity in the dynamics of vegetation types tested, with annual cycles of plant growth and higher Enhanced Vegetation Index values in spring and summer and lower Enhanced Vegetation Index values in autumn and winter.

Tatiana M., Kuplich; Andreise, Moreira; Denise C., Fontana.

44

How Normalized Difference Vegetation Index (NDVI Trendsfrom Advanced Very High Resolution Radiometer (AVHRR and Système Probatoire d’Observation de la Terre VEGETATION (SPOT VGT Time Series Differ in Agricultural Areas: An Inner Mongolian Case Study  

Directory of Open Access Journals (Sweden)

Full Text Available Detailed information from global remote sensing has greatly advanced ourunderstanding of Earth as a system in general and of agricultural processes in particular.Vegetation monitoring with global remote sensing systems over long time periods iscritical to gain a better understanding of processes related to agricultural change over longtime periods. This specifically relates to sub-humid to semi-arid ecosystems, whereagricultural change in grazing lands can only be detected based on long time series. Byintegrating data from different sensors it is theoretically possible to construct NDVI timeseries back to the early 1980s. However, such integration is hampered by uncertainties inthe comparability between different sensor products. To be able to rely on vegetationtrends derived from integrated time series it is therefore crucial to investigate whether vegetation trends derived from NDVI and phenological parameters are consistent acrossproducts. In this paper we analyzed several indicators of vegetation change for a range ofagricultural systems in Inner Mongolia, China, and compared the results across differentsatellite archives. Specifically, we compared two of the prime NDVI archives—AVHRR Global Inventory Modeling and Mapping Studies (GIMMS and SPOT Vegetation (VGTNDVI. Because a true accuracy assessment of long time series is not possible, we furthercompared SPOT VGT NDVI with NDVI from MODIS Terra as a benchmark. We foundhigh similarities in interannual trends, and also in trends of the seasonal amplitude andintegral between SPOT VGT and MODIS Terra (r > 0.9. However, we observedconsiderable disagreements in NDVI-derived trends between AVHRR GIMMS and SPOTVGT. We detected similar discrepancies for trends based on phenological parameters, suchas amplitude and integral of NDVI curves corresponding to seasonal vegetation cycles.Inconsistencies were partially related to land cover and vegetation density. Differentpre-processing schemes and the coarser spatial resolution of AVHRR GIMMS introducedfurther uncertainties. Our results corroborate findings from other studies that vegetationtrends derived from AVHRR GIMMS data not always reflect true vegetation changes. Amore thorough understanding of the factors introducing uncertainties in AVHRR GIMMStime series is needed, and we caution against using AVHRR GIMMS data in regionalstudies without applying regional sensitivity analyses. 

Patrick Hostert

2012-11-01

45

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)

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.

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

46

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.

2009-10-01

47

Functional analysis of normalized difference vegetation index curves reveals overwinter mule deer survival is driven by both spring and autumn phenology.  

Science.gov (United States)

Large herbivore populations respond strongly to remotely sensed measures of primary productivity. Whereas most studies in seasonal environments have focused on the effects of spring plant phenology on juvenile survival, recent studies demonstrated that autumn nutrition also plays a crucial role. We tested for both direct and indirect (through body mass) effects of spring and autumn phenology on winter survival of 2315 mule deer fawns across a wide range of environmental conditions in Idaho, USA. We first performed a functional analysis that identified spring and autumn as the key periods for structuring the among-population and among-year variation of primary production (approximated from 1 km Advanced Very High Resolution Radiometer Normalized Difference Vegetation Index (NDVI)) along the growing season. A path analysis showed that early winter precipitation and direct and indirect effects of spring and autumn NDVI functional components accounted for 45% of observed variation in overwinter survival. The effect size of autumn phenology on body mass was about twice that of spring phenology, while direct effects of phenology on survival were similar between spring and autumn. We demonstrate that the effects of plant phenology vary across ecosystems, and that in semi-arid systems, autumn may be more important than spring for overwinter survival. PMID:24733951

Hurley, Mark A; Hebblewhite, Mark; Gaillard, Jean-Michel; Dray, Stéphane; Taylor, Kyle A; Smith, W K; Zager, Pete; Bonenfant, Christophe

2014-01-01

48

Functional analysis of Normalized Difference Vegetation Index curves reveals overwinter mule deer survival is driven by both spring and autumn phenology  

Science.gov (United States)

Large herbivore populations respond strongly to remotely sensed measures of primary productivity. Whereas most studies in seasonal environments have focused on the effects of spring plant phenology on juvenile survival, recent studies demonstrated that autumn nutrition also plays a crucial role. We tested for both direct and indirect (through body mass) effects of spring and autumn phenology on winter survival of 2315 mule deer fawns across a wide range of environmental conditions in Idaho, USA. We first performed a functional analysis that identified spring and autumn as the key periods for structuring the among-population and among-year variation of primary production (approximated from 1 km Advanced Very High Resolution Radiometer Normalized Difference Vegetation Index (NDVI)) along the growing season. A path analysis showed that early winter precipitation and direct and indirect effects of spring and autumn NDVI functional components accounted for 45% of observed variation in overwinter survival. The effect size of autumn phenology on body mass was about twice that of spring phenology, while direct effects of phenology on survival were similar between spring and autumn. We demonstrate that the effects of plant phenology vary across ecosystems, and that in semi-arid systems, autumn may be more important than spring for overwinter survival.

Hurley, Mark A.; Hebblewhite, Mark; Gaillard, Jean-Michel; Dray, Stephane; Taylor, Kyle A.; Smith, W. K.; Zager, Pete; Bonenfant, Christophe

2014-01-01

49

[Extraction of structured vegetation cover index for Loess Area in North Shaanxi based on TM images].  

Science.gov (United States)

Based on the concept of structured vegetation cover index (Cs) and by using TM images as the information source, the extraction way of Cs for Loess Area in North Shaanxi by using remote sensing techniques was explored. In study area, Cs was better than the traditional projected vegetation coverage index in expressing the relationships between vegetation structure and soil erosion. The Cs was closely related to the remote sensing vegetation indices, such as green indices NDVI (Normalized Difference Vegetation Index) and MSAVI (Modified Soil Adjusted Vegetation Index), and yellow indices NDSVI (Difference Senescent Vegetation Index) and NDTI (Normalized Difference Tillage Index). The combination of the green and yellow indices could better express the effects of vegetation on soil erosion, compared with the single index. Among these remote sensing vegetation indices, the MSAVI and NDTI could be the ideal green and yellow vegetation indices for the extraction of Cs from TM images. It was possible to extract the Cs from remote sensing data through the regression analysis of Cs and remote sensing vegetation indices. However, this method was just validated and applied to the study area. Whether it could be applied to other regions was needed to be further validated due to the phonological differences from one region to another. PMID:20136009

Lei, Wan-Ning; Wen, Zhong-Ming

2009-11-01

50

A high-resolution index for vegetation extraction in IKONOS images  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In monitoring vegetation change and urban planning, the measure and the mapping of the green vegetation over the Earth play an important role. The normalized difference vegetation index (NDVI) is the most popular approach to generate vegetation maps for remote sensing imagery. Unfortunately, the NDVI generates low resolution vegetation maps. Highresolution imagery, such as IKONOS imagery, can be used to overcome this weakness leading to better classification accuracy. Hence, it is important t...

Chikr El-mezouar, Miloud; Taleb, Nasreddine; Kpalma, Kidiyo; Ronsin, Joseph

2010-01-01

51

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)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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.

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

52

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

Directory of Open Access Journals (Sweden)

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.

Ainong Li

2010-06-01

53

[Using Kerdo index to evaluate vegetative homeostasis].  

Science.gov (United States)

The authors analyse efficiency of various approaches to evaluation of vegetative balance in submariners and fishing sailors. The article covers suggestions of approaches to regulate parameters of vegetative balance, considerations of some features forming averages of studied values in sailors. The authors recommend evaluation of vegetative tone through description of regulatory mechanisms strain. PMID:15581090

Myznikov, I L; Shcherbina, F A

2004-01-01

54

Global Data Sets of Vegetation Leaf Area Index (LAI)3g and Fraction of Photosynthetically Active Radiation (FPAR)3g Derived from Global Inventory Modeling and Mapping Studies (GIMMS) Normalized Difference Vegetation Index (NDVI3g) for the Period 1981 to 2011  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Long-term global data sets of vegetation Leaf Area Index (LAI) and Fraction of Photosynthetically Active Radiation absorbed by vegetation (FPAR) are critical to monitoring global vegetation dynamics and for modeling exchanges of energy, mass and momentum between the land surface and planetary boundary layer. LAI and FPAR are also state variables in hydrological, ecological, biogeochemical and crop-yield models. The generation, evaluation and an example case study documenting the utility of 30...

2013-01-01

55

STUDY ON THE VARIABILITY OF "NORMALIZED DIFFERENCE VEGETATION INDEX/NDVI" BY INDICATIVE KRIGING = ESTUDO DA VARIABILIDADE DO "ÍNDICE DE VEGETAÇÃO POR DIFERENÇA NORMALIZADA/NDVI" UTILIZANDO KRIGAGEM INDICATIVA  

Directory of Open Access Journals (Sweden)

Full Text Available The main purpose of this paper was to evaluate the “Normalized Difference Vegetation Index” (NDVI in an area at Baixada Santista, coastland of São Paulo State, Brazil, using the geostatistic technique of indicative kriging. The analyses were made using sensor TM images (Landsat satellite, dated from February/1989 and January/1997. The obtained NDVI maps showed vegetation loss during the analyzed period, and the probabilities map, resulting from the difference between the two periods of time, indicated a distinct contrast between loss and gains of vegetation index. Vegetation mapping and application of indicative kriging were shown as beingquite useful for monitoring and environmental management, being able to provide good results when jointly used. = Este trabalho teve por objetivo principal analisar o “índice de vegetação por diferença normalizada” (NDVI em uma área da Baixada Santista, litoral paulista,utilizando a técnica geoestatística da krigagem indicativa. As análises foram feitas em imagens do sensor TM do satélite Landsat datadas de fevereiro de 1989 e janeiro de 1997. Os mapas obtidos do NDVI mostraram perda de vegetação de um modo geral, durante o período analisado, e o mapa de probabilidades resultante da diferença entreos dois períodos indicou forte contraste entre perdas e ganhos do índice de vegetação. O mapeamento da vegetação e a aplicação da krigagem indicativa mostraram-se ferramentas de grande aplicabilidade para o monitoramento e gerenciamento ambiental e podem proporcionar bons resultados quando utilizadas de forma integrada.

Roberto Wagner Lourenço

2004-01-01

56

How Normalized Difference Vegetation Index (NDVI) Trendsfrom Advanced Very High Resolution Radiometer (AVHRR) and Système Probatoire d’Observation de la Terre VEGETATION (SPOT VGT) Time Series Differ in Agricultural Areas: An Inner Mongolian Case Study  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Detailed information from global remote sensing has greatly advanced ourunderstanding of Earth as a system in general and of agricultural processes in particular.Vegetation monitoring with global remote sensing systems over long time periods iscritical to gain a better understanding of processes related to agricultural change over longtime periods. This specifically relates to sub-humid to semi-arid ecosystems, whereagricultural change in grazing lands can only be detected based on long time ...

He Yin; Thomas Udelhoven; Rasmus Fensholt; Dirk Pflugmacher; Patrick Hostert

2012-01-01

57

Routine Mapping of Vegetation Index with the AVHRR of NOAA11.  

Science.gov (United States)

Daytime and nightime AVHRR (Advanced Very High Resolution Radiometer) data from NOAA 11 are routinely processed for different meteorological purposes, such as the cloud cover description. The use of this automatic scheme to achieve vegetation index mappin...

P. Brunel M. Derrien H. Legleau A. Marsouin

1991-01-01

58

An initial assessment of Suomi NPP VIIRS vegetation index EDR  

Science.gov (United States)

The Suomi National Polar-orbiting Partnership (S-NPP) satellite with Visible/Infrared Imager/Radiometer Suite (VIIRS) onboard was launched in October 2011. VIIRS is the primary instrument for a suite of Environmental Data Records (EDR), including Vegetation Index (VI) EDR, for weather forecasting and climate research. The VIIRS VI EDR operational product consists of the Top of the Atmosphere (TOA) Normalized Difference Vegetation Index (NDVI), the Top of the Canopy (TOC) Enhanced Vegetation Index (EVI), and per-pixel product quality information. In this paper, we report results of our assessment of the early VIIRS VI EDR (beta quality) using Aqua MODIS and NOAA-18 AVHRR/3 as a reference for May 2012 to March 2013. We conducted two types of analyses focused on an assessment of physical (global scale) and radiometric (regional scale) performances of VIIRS VI EDR. Both TOA NDVI and TOC EVI of VIIRS showed spatial and temporal trends consistent with the MODIS counterparts, whereas VIIRS TOA NDVI was systematically higher than that of AVHRR. Performance of the early VIIRS VI EDR was limited by a lack of adequate per-pixel quality information, commission/omission errors of the cloud mask, and uncertainties associated with the surface reflectance retrievals. A number of enhancements to the VI EDR are planned, including: (1) implementation of a TOC EVI back-up algorithm, (2) addition of more detailed quality flags on aerosols, clouds, and snow cover, and (3) implementation of gridding and temporal compositing. A web-based, product quality monitoring tool has been developed and automated product validation protocols are being prototyped.

Vargas, M.; Miura, T.; Shabanov, N.; Kato, A.

2013-11-01

59

Global Data Sets of Vegetation Leaf Area Index (LAI3g and Fraction of Photosynthetically Active Radiation (FPAR3g Derived from Global Inventory Modeling and Mapping Studies (GIMMS Normalized Difference Vegetation Index (NDVI3g for the Period 1981 to 2011  

Directory of Open Access Journals (Sweden)

Full Text Available Long-term global data sets of vegetation Leaf Area Index (LAI and Fraction of Photosynthetically Active Radiation absorbed by vegetation (FPAR are critical to monitoring global vegetation dynamics and for modeling exchanges of energy, mass and momentum between the land surface and planetary boundary layer. LAI and FPAR are also state variables in hydrological, ecological, biogeochemical and crop-yield models. The generation, evaluation and an example case study documenting the utility of 30-year long data sets of LAI and FPAR are described in this article. A neural network algorithm was first developed between the new improved third generation Global Inventory Modeling and Mapping Studies (GIMMS Normalized Difference Vegetation Index (NDVI3g and best-quality Terra Moderate Resolution Imaging Spectroradiometer (MODIS LAI and FPAR products for the overlapping period 2000–2009. The trained neural network algorithm was then used to generate corresponding LAI3g and FPAR3g data sets with the following attributes: 15-day temporal frequency, 1/12 degree spatial resolution and temporal span of July 1981 to December 2011. The quality of these data sets for scientific research in other disciplines was assessed through (a comparisons with field measurements scaled to the spatial resolution of the data products, (b comparisons with broadly-used existing alternate satellite data-based products, (c comparisons to plant growth limiting climatic variables in the northern latitudes and tropical regions, and (d correlations of dominant modes of interannual variability with large-scale circulation anomalies such as the EI Niño-Southern Oscillation and Arctic Oscillation. These assessment efforts yielded results that attested to the suitability of these data sets for research use in other disciplines. The utility of these data sets is documented by comparing the seasonal profiles of LAI3g with profiles from 18 state-of-the-art Earth System Models: the models consistently overestimated the satellite-based estimates of leaf area and simulated delayed peak seasonal values in the northern latitudes, a result that is consistent with previous evaluations of similar models with ground-based data. The LAI3g and FPAR3g data sets can be obtained freely from the NASA Earth Exchange (NEX website.

Ranga B. Myneni

2013-02-01

60

An Assessment of Mining Activities Impact on Vegetation in Bukuru Jos Plateau State Nigeria Using Normalized Differential Vegetation Index (NDVI  

Directory of Open Access Journals (Sweden)

Full Text Available The study area has a pathetic and deplorable condition of landuse/ landcover. The vegetal cover in the area has to be removed from the activities of tin mining which consequently resulted into adverse environmental effect such as erosion. Different forms of human induced stress such as tin mining and heavy rainfall have severely degraded soils on the Jos Plateau. Such degradation problems are also caused by deforestation, inappropriate farming system, bush burning and over-grazing which are hostile to the environment. The impact of tin mining has greatly affected the natural ecology of the study area Bukuru. Micro and macro organisms and plants have been stripped off their natural habitat due to tin mining activities. This paper therefore, assesses the mining activities impact on the vegetation in Bukuru area of Jos plateau in Nigeria. Normalized Differential Vegetation Index (NDVI techniques was adopted to Maps effect of tin mining on the vegetation for the period between 1975 and 2007 using LandSat satellite data. The result of the differential vegetation index analysis reveals a decline in vegetated surfaces in 1986 ranging from 0.04 to 0.58 indicating 0.05 and continuous loss in vegetation over the study area in 2007 (vegetated surface decrease by 0.08 between 1986 and 2007. The decrease in vegetated surface is due to intensive mining and cultivation.

Musa Haruna D.

2011-11-01

 
 
 
 
61

Test of Multi-spectral Vegetation Index for Floating and Canopy-forming Submerged Vegetation  

Directory of Open Access Journals (Sweden)

Full Text Available Remote sensing of terrestrial vegetation has been successful thanks to the unique spectral characteristics of green vegetation, low reflectance in red and high reflectance in Near-InfraRed (NIR. These spectral characteristics were used to develop vegetation indices, including Normalized Difference Vegetation Index (NDVI. However, the NIR absorption by water and light scattering from suspended particles reduces the practical application of such indices in aquatic vegetation studies, especially for the Submerged Aquatic Vegetation (SAV that grows below water surface. We experimentally tested if NDVI can be used to depict canopies of aquatic plants in shallow waters. A 100-gallonoutdoor tank was lined with black pond liners, a black panel or SAV shoots were mounted on the bottom, and filled with water up to 0.5 m. We used a GER 1500 spectroradiometer to collect spectral data over floating waterhyacinth (Eichhornia crassipes and also over the tanks that contain SAV and black panel at varying water depths. The measured upwelling radiance was converted to % reflectance; and we integrated the hyperspectral reflectance to match the Red and NIR bands of three satellite sensors: Landsat 7 ETM, SPOT 5 HRG, and ASTER. NDVI values ranged 0.6-0.65 when the SAV canopy was at the water level, then they decreased linearly (slope of 0.013 NDVI/meter with water depth increases in clear water. When corrected for water attenuation using the data obtained from the black panel, the NDVI values significantly increased at all depths that we tested (0.1 – 0.5 m. Our results suggest the conventional NDVI: (1 can be used to depict SAV canopies at water surface; (2 is not a good indicator for SAV that is adapted to live underwater or other aquatic plants that are submerged during flooding even at shallow waters (0.3 m; and (3 the index values can significantly improve if information on spectral reflectance attenuation caused by water volume increases is collected simultaneously through ground-truthing and integrated.

Philemon Kirui

2008-12-01

62

Analysis of Vegetation Index Variations and the Asian Monsoon Climate  

Science.gov (United States)

Vegetation growth depends on local climate. Significant anthropogenic land cover and land use change activities over Asia have changed vegetation distribution as well. On the other hand, vegetation is one of the important land surface variables that influence the Asian Monsoon variability through controlling atmospheric energy and water vapor conditions. In this presentation, the mean and variations of vegetation index of last decade at regional scale resolution (5km and higher) from MODIS have been analyzed. Results indicate that the vegetation index has been reduced significantly during last decade over fast urbanization areas in east China, such as Yangtze River Delta, where local surface temperatures were increased significantly in term of urban heat Island. The relationship between vegetation Index and climate (surface temperature, precipitation) over a grassland in northern Asia and over a woody savannas in southeast Asia are studied. In supporting Monsoon Asian Integrated Regional Study (MAIRS) program, the data in this study have been integrated into Giovanni, the online visualization and analysis system at NASA GES DISC. Most images in this presentation are generated from Giovanni system.

Shen, Sunhung; Leptoukh, Gregory G.; Gerasimov, Irina

2012-01-01

63

Comparisons among a new soil index and other two- and four-dimensional vegetation indices  

Science.gov (United States)

The 2-D difference vegetation index (DVI) and perpendicular vegetation index (PVI), and the 4-D green vegetation index (GVI) are compared in LANDSAT MSS data from grain sorghum (Sorghum bicolor, L. Moench) fields for the years 1973 to 1977. PVI and DVI were more closely related to LAI than was GVI. A new 2-D soil line index (SLI), the vector distance from the soil line origin to the point of intersection of PVI with the soil line, is defined and compared with the 4-D soil brightness index, SBI. SLI (based on MSS and MSS7) and SL16 (based on MSS 5 and MSS 6) were smaller in magnitude than SBI but contained similar information about the soil background. These findings indicate that vegetation and soil indices calculated from the single visible and reflective infrared band sensor systems, such as the AVHRR of the TIROS-N polar orbiting series of satellites, will be meaningful for synoptic monitoring of renewable vegetation.

Wiegand, C. L.; Richardson, A. J. (principal investigators)

1982-01-01

64

Vegetation  

DEFF Research Database (Denmark)

â?¢ 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%. â?¢ 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. â?¢ 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.

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

2012-01-01

65

Distinguishing land use types using surface albedo and normalized difference vegetation index derived from the SEBAL model for the Atankwidi and Afram sub-catchments in Ghana  

Directory of Open Access Journals (Sweden)

Full Text Available Distinguishing land use types is mostly done through field surveys which does not easily capture the spatial changes in the land use/cover types. In this study, the Surface Energy Balance Algorithm for Land (SEBAL model was used to estimate surface albedo and NDVI, for different land use/cover types for two sub-catchments (i.e., Atankwidi and Afram in the Volta Basin of Ghana. The mean coefficient of variation (CV for individual land use/cover types compared to the mean CV for a given site was then used to distinguish among the land use/cover types. It was found that these parameters derived from the SEBAL model can be used to distinguish among different land use/cover types in the two sub-catchments. SEBAL estimates for surface albedo and NDVI across the different land use/cover types varied from 0.05 to 0.22 and -0.41 to 0.38, respectively. The range of CVs for surface albedo and NDVI, were 5-22% and 7-175%, respectively across the different land use/cover types for the two catchments. The results of this study demonstrate that SEBAL’s derived surface albedo and NDVI can be used to distinguish land use/cover types in catchments similar to those of the study areas with few ground measurements.

Tayari Salifu

2012-01-01

66

Validating a Dynamic Global Vegetation Model with Remotely Sensed Vegetation Index  

Directory of Open Access Journals (Sweden)

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.

Jiaxin Jin

2013-02-01

67

[Construction of vegetation shadow index (SVI) and application effects in four remote sensing images].  

Science.gov (United States)

Taking the images of Landsat TM, ALOS AVNIR-2, CBERS-02B CCD and HJ-1 CCD as the experimental data, for increasing the differences among shaded area, bright area and water further, the present paper construed a novel vegetation index-Shaded Vegetation Index(SVI), which can not only keep the absolute differences among bright area, shaded area and water area in the near-infrared band, but also can enlarge NDVI, eliminate the possible mixes, and change the histogram "skewed" phenomenon of NDVI, so the vegetation index value is closer to normal distribution, and more in line with the filed condition; this new index was applied to the surface features of large difference of the near-infrared radiation characteristics. Verified by accuracy assessment for the bright area, shaded area and water area recognition effects with SVI, it was showed that the overall classification accuracies of these images were up to 98. 89%, 100%, 97.78% and 97.78% respectively, with the overall Kappa statistics of 0.9833, 1, 0.9667, and 0.966 7, indicating that SVI has excellent detection effects for bright area, shaded area and water area; the statistical comparison of sub-images between SVI and NDVI also illustrated the reliability and effectiveness of SVI, which can be applied in the shadow removal for remote sensing images. PMID:24611403

Xu, Zhang-Hua; Liu, Jian; Yu, Kun-Yong; Liu, Tao; Gong, Cong-Hong; Tang, Meng-Ya; Xie, Wan-Jun; Li, Zeng-Lu

2013-12-01

68

Multisensor reflectance and vegetation index comparisons of Amazon tropical forest phenology with hyperspectral Hyperion data  

Science.gov (United States)

Current earth observing satellite sensors have different temporal, spectral and spatial characteristics that present problems in the establishment of long term, time series data records. Vegetation indices (VI's) are commonly used in deriving long term measures of vegetation biophysical properties, which have been shown useful in interannual climate studies and phenology studies. While significant improvements have been made with new sensors, and algorithms, and processing methods, backward compatibility of VI's is desired so that the long term record can extend back and utilize the AVHRR record to 1981. Conversely, any reprocessing of the AVHRR record should consider steps to allow forward compatibility with newer sensors and products. In this study we evaluated the use of sensor-specific enhanced vegetation index (EVI) and normalized difference vegetation index (NDVI) data sets, using a time sequence of Hyperion images over Tapajos National Forest in Brazil over the 2001 and 2002 dry seasons. We computed NDVI, EVI, and a 2-band version of EVI (EVI2) for different sensor systems (AVHRR, MODIS, VIIRS, SPOT-VGT, and SeaWiFS) and evaluated their differences and continuity in the characterization of tropical forest phenology. We also analyzed the influence of different atmosphere correction scenarios to assess noise in the phenology signal. Our analyses show that EVI2 maintains the desirable properties of increased sensitivity in high biomass forests across all sensor systems evaluated in this study. We further conclude that EVI2 can be extended to the AVHRR time series record and compliment that current NDVI time series record.

Kim, Youngwook; Huete, Alfredo R.; Jiang, Zhangyan; Miura, Tomoaki

2007-10-01

69

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

Science.gov (United States)

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

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

2012-12-01

70

Estimation of Air Temperature Using Temperature-Vegetation Index (TVX Method  

Directory of Open Access Journals (Sweden)

Full Text Available The determination of air temperature is important in the energy balance calculation, hydrology and meteorological studies. In this regard, the limited number of meteorological stations is one of the serious problems for air temperature determination on a large spatial scale. The remote sensing technique by covering large areas and using updated satellite images might be appropriate for estimation of this parameter. In this research, the negative correlation between land surface temperature and vegetation index (NDVI has been used for air temperature estimation through TVX method in which the inference of air temperature is based on the hypothesis that the temperature of the dense vegetation canopy is close to air temperature. For investigation the performance of TVX method, images of MODIS sensor have been applied for the Sefidrod River basin in the years 1381- 1382-1384. The spilt window technique which was developed by Price has been used for land surface temperature calculation. The mean difference between observed and estimated land surface temperature using Price algorithm was about 6.2Co. This error can affect the air temperature values. Because of using NDVI index in TVX method, this method has the sensitivity to the vegetation density, though in the parts with sparse vegetation, the value of error increases. 4 percent variation of air temperature against the 0.05 increasing of maximum NDVI indicates the high performance of TVX method for air temperature estimation in large areas.

L. Parviz

2011-07-01

71

Influência da direção de semeadura do milho nas variáveis reflectância e índice de vegetação verde normalizado / Influence of the row direction of corn on the reflectance and green normalized difference vegetation index  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Com este trabalho, objetivou-se estudar a influência da direção de semeadura do milho (Zea Mays L.) na sua reflectância na banda 550 nm (r550) e no Índice de Vegetação Verde da Diferença Normalizado - IVVDN, visando fornecer informações necessárias à viabilização de um sistema de aplicação localizad [...] a de nitrogênio (N) em tempo real. O sistema de semeadura utilizado foi o direto, administrando-se os nutrientes de acordo com análise do solo e com uma taxa de N de 160 kg ha-1. As linhas de semeadura foram localizadas na direção Norte-Sul e Leste-Oeste. Conclui-se que o milho semeado na direção Leste-Oeste apresentou valores para reflectância r550 e índice de vegetação IVVDN menores e menos dependente da hora do dia que o milho semeado na direção Norte-Sul. O IVVDN mostrou-se mais apropriado para uso em sistemas de aplicação de fertilizantes a taxas variáveis em tempo real utilizando-se técnicas de sensoriamento remoto, por se mostrar menos sensível á direção de semeadura. Abstract in english The objective of this work was to study the influence of the row direction of corn (Zea mays) on its spectral properties measured in the field, including the green normalized difference vegetation index (Green NDVI). Spectral properties of corn are known to be related to the nitrogen (N) status of t [...] he corn and may form the basis for real-time site-specific rates of N application. Row direction effects on spectral properties may be substantial before canopy closure. If so, it will be necessary to account for these effects in order to accurately predict the N need of corn from spectral measurements. Corn was planted directly, with no tillage, in North-South (NS) and East-West (EW) oriented rows. Nitrogen was applied as ammonium nitrate at a rate of 160 kg N ha-1. Reflectance was measured with spectral radiometers placed 30 cm above individual plants. Reflectance and green NDVI were bly dependent on time of day for corn in NS rows, and much less so for corn in EW rows. Reflectance and green NDVI were lower for corn in EW rows than corn in NS rows, but lack of replication makes it difficult to be certain that this was due to row direction. Green NDVI was less sensitive than reflectance to row direction and therefore may be more appropriate for use in a real-time variable-rate nitrogen application system.

Souza, Eduardo G. de; Orlando, Gracielle A.; Uribe-Opazo, Miguel A.; Silva, Edson A. da; Scharf, Peter.

72

Vegetative Growth Performance of Different Plum Rootstocks  

Directory of Open Access Journals (Sweden)

Full Text Available The study was conducted to investigate the vegetative growth performance of Damascos, Myrobalan and Desi plum (Prunus domistica L. rootstocks propagated by hardwood cuttings at Peshawar, during 1999. Desi (Local plum gained maximum number (176.75 of roots, root length (58.75 cm, shoot length (375.95 cm, shoot diameter (1.82 cm and survival (73.33 percentage, while there was no differences in the sprouting percentage among all rootstocks.

Noor Rahman

2000-01-01

73

Vegetative Growth Performance of Different Plum Rootstocks  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The study was conducted to investigate the vegetative growth performance of Damascos, Myrobalan and Desi plum (Prunus domistica L.) rootstocks propagated by hardwood cuttings at Peshawar, during 1999. Desi (Local) plum gained maximum number (176.75) of roots, root length (58.75 cm), shoot length (375.95 cm), shoot diameter (1.82 cm) and survival (73.33 ) percentage, while there was no differences in the sprouting percentage among all rootstocks.

Noor Rahman; Ghulam Nabi; Jamsher Khan; Shafqatullah

2000-01-01

74

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

2009-01-01

75

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

Science.gov (United States)

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.

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

2012-03-01

76

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

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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.

Timothy J. Fullman

2014-01-01

77

Recent droughts and the impact of North Atlantic Oscillation in Iberia; a spatiotemporal analysis based on vegetation temperature condition Index (VTCI)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Drought is a complex phenomenon that afflicts huge areas worldwide with high spatial and temporal variability. Being under influence of the Mediterranean climate the Iberian Peninsula is per se prone to droughts. In this study, we applied the Vegetation Condition Temperature Index for a spatiotemporal drought analysis in Iberia. As a compound remote sensing drought index VTCI incorporates information on Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature ...

Mu?hlbauer, Stefan Ludwig

2013-01-01

78

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 algorith...

Nagler, Pamela L.; Glenn, Edward P.; Uyen Nguyen; Scott, Russell L.; Tanya Doody

2013-01-01

79

Estimate soil moisture using trapezoidal relationship between remotely sensed land surface temperature and vegetation index  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The trapezoidal relationship between surface temperature (Ts) and vegetation index (VI) was used to estimate soil moisture in the present study. An iterative algorithm is proposed to estimate the vertices of the Ts~VI trapezoid theoretically for each grid, and then WDI is calculated for each grid using MODIS remotely sensed measurements of surface temperature and enhanced vegetation index (EVI). The capability...

Wang, W.; Huang, D.; -g Wang, X.; -r Liu, Y.; Zhou, F.

2010-01-01

80

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

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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.

John H. Prueger

2010-02-01

 
 
 
 
81

Vegetation Index Methods for Estimating Evapotranspiration by Remote Sensing  

Science.gov (United States)

Evapotranspiration (ET) is the largest term after precipitation in terrestrial water budgets. Accurate estimates of ET are needed for numerous agricultural and natural resource management tasks and to project changes in hydrological cycles due to potential climate change. We explore recent methods that combine vegetation indices (VI) from satellites with ground measurements of actual ET (ETa) and meteorological data to project ETa over a wide range of biome types and scales of measurement, from local to global estimates. The majority of these use time-series imagery from the Moderate Resolution Imaging Spectrometer on the Terra satellite to project ET over seasons and years. The review explores the theoretical basis for the methods, the types of ancillary data needed, and their accuracy and limitations. Coefficients of determination between modeled ETa and measured ETa are in the range of 0.45-0.95, and root mean square errors are in the range of 10-30% of mean ETa values across biomes, similar to methods that use thermal infrared bands to estimate ETa and within the range of accuracy of the ground measurements by which they are calibrated or validated. The advent of frequent-return satellites such as Terra and planed replacement platforms, and the increasing number of moisture and carbon flux tower sites over the globe, have made these methods feasible. Examples of operational algorithms for ET in agricultural and natural ecosystems are presented. The goal of the review is to enable potential end-users from different disciplines to adapt these methods to new applications that require spatially-distributed ET estimates.

Glenn, Edward P.; Nagler, Pamela L.; Huete, Alfredo R.

2010-12-01

82

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

Directory of Open Access Journals (Sweden)

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.

Russell L. Scott

2013-08-01

83

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

Science.gov (United States)

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.

Wan, Zhengming

2002-01-01

84

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  

Directory of Open Access Journals (Sweden)

Full Text Available The objective of this study was to analyze the pattern spatial-temporal values of the Normalized DifferenceVegetation Index (NDVI in Itapeva-RS lake, using Landsat TM5 and ETM + 7 images, from1985 through 2010. For the analysis of space-temporal behavior classes was used Normalized DifferenceVegetation Index (NDVI classes and Temporal Series Analysis (TSA. To validate the observed patternswere collected water samples from six points in the Itapeva Lake for clorofila_a, Total suspendedsolids and Secchi disk transparency. These results were correlated with NDVI values. The NDVI classesmaps generated after analysis of TSA, showed dynamic patterns of seasonal and spatial associated withenvironmental variables that were actuating, allowing the establishment of three distinctive surfaces inItapeva Lake: north, center and south. The Temporal Series Analysis of images shows that the increaseand decrease of NDVI values are associated with periods of phytoplankton bloom. One concluded thatthe Temporal Series Analysis of Landsat images was satisfactory with regard to the behavior of spatialand temporal variation of NDVI classes.

2013-10-01

85

Evaluation of Digital Hemispherical Photography and Plant Canopy Analyzer for Measuring Vegetation Area Index of Orange Orchards  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study presents the results of an evaluation of two indirect methods (Plant Canopy Analyzer (PCA) and hemispherical photographs) for measuring Vegetation Area Index (VAI) of two orange orchards, differing by their ground fraction cover (fc). The evaluation is based on reference data obtained by destructive measurements on limited samples, which allow to calibrate and validate an exponential relationship between the diameter of branches and associated areas of leaves (R2

Khabba, S.; Duchemin, B.; Hadria, R.; Er-raki, S.; Ezzahar, J.; Chehbouni, A.; Lahrouni, A.; Hanich, L.

2009-01-01

86

Monitoring responses of Mason Pine to acid rain in China based on remote sensing vegetation index  

Science.gov (United States)

Since the 1970s, acid rain has remained in the public spotlight in both Europe and the United States and recently has emerged as an important problem in other regions such as Southeast Asia. To reveal responses of Masson Pine to acid rain during a long time series in central China, we used the interpolation dataset of acid rain and the Global Inventory Modeling and Mapping Studies (GIMMS) normalized difference vegetation index (NDVI) data to derive the monthly pH and NDVI trajectories based on acidity gradients from 1992 to 2006. Then we analyzed inter-annual and seasonal variation of vegetation growth by improved sinusoidal fitting and regression analysis. In the environment of strong acidity and moderate acidity, the growth of Masson Pine was inhibited during the study period, while the slight acidity promoted growth of Masson Pine to some extent. For the multi-year monthly changing trend of NDVI, late spring to mid autumn, the NDVI showed a decreasing trend, especially in June, while from late autumn to the following spring, the NDVI showed a rising tendency, specifically in December and March.

Jin, Jiaxin; Jiang, Hong; Hou, Chunliang; Zhang, Xiuying; Wang, Ying

2014-03-01

87

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

Directory of Open Access Journals (Sweden)

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.

Teruel Bárbara

2004-01-01

88

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

Directory of Open Access Journals (Sweden)

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.

Ishimura A

2011-11-01

89

Spatiotemporal analysis of vegetation index after typhoons in the mountainous watershed  

Science.gov (United States)

An extensive land cover change was triggered by a series of typhoons, especially Typhoon Morakot in 2009 in Taiwan. The normalized difference vegetation index (NDVI) series from multiple satellite images were applied to monitor the change processes of land cover. This study applied spatiotemporal analysis tools, including empirical orthogonal functions (EOF), and multiple variograms in analyzing space-time NDVI data, and detected the effects of large chronological disturbances in the characteristics of land cover changes. Spatiotemporal analysis delineated the temporal patterns and spatial variability of NDVI caused by these large typhoons. Results showed that mean of NDVI decreased but spatial variablity of NDVI increased after typhoons in the study area. The EOF can clarify the major component of NDVI variations and identify the core area of the NDVI changes. Various approaches showed consistent results that Typhoon Morakot significantly lowered the NDVI in land cover change process. Furthermore, the spatiotemporal analysis is an effective monitoring tool, which advocates the use of the index for the quantification of land cover change and resilience.

Chu, Hone-Jay

2014-05-01

90

Estimating Crop Coefficients Using Remote Sensing-Based Vegetation Index  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 sate...

Baburao Kamble; Ayse Irmak; Kenneth Hubbard

2013-01-01

91

Savanna vegetation-fire-climate relationships differ among continents.  

Science.gov (United States)

Ecologists have long sought to understand the factors controlling the structure of savanna vegetation. Using data from 2154 sites in savannas across Africa, Australia, and South America, we found that increasing moisture availability drives increases in fire and tree basal area, whereas fire reduces tree basal area. However, among continents, the magnitude of these effects varied substantially, so that a single model cannot adequately represent savanna woody biomass across these regions. Historical and environmental differences drive the regional variation in the functional relationships between woody vegetation, fire, and climate. These same differences will determine the regional responses of vegetation to future climates, with implications for global carbon stocks. PMID:24482480

Lehmann, Caroline E R; Anderson, T Michael; Sankaran, Mahesh; Higgins, Steven I; Archibald, Sally; Hoffmann, William A; Hanan, Niall P; Williams, Richard J; Fensham, Roderick J; Felfili, Jeanine; Hutley, Lindsay B; Ratnam, Jayashree; San Jose, Jose; Montes, Ruben; Franklin, Don; Russell-Smith, Jeremy; Ryan, Casey M; Durigan, Giselda; Hiernaux, Pierre; Haidar, Ricardo; Bowman, David M J S; Bond, William J

2014-01-31

92

Estimating soil moisture and the relationship with crop yield using surface temperature and vegetation index  

Science.gov (United States)

Soil moisture availability affects rainfed crop yield. Therefore, the development of methods for pre-harvest yield prediction is essential for the food security. A study was carried out to estimate regional crop yield using the Temperature Vegetation Dryness Index (TVDI). Triangular scatters from land surface temperature (LST) and enhanced vegetation index (EVI) space from MODIS (Moderate Resolution Imaging Spectroradiometer) were utilized to obtain TVDI and to estimate soil moisture availability. Then soybean and wheat crops yield was estimated on four agro-climatic zones of Argentine Pampas. TVDI showed a strong correlation with soil moisture measurements, with R2 values ranged from 0.61 to 0.83 and also it was in agreement with spatial pattern of soil moisture. Moreover, results showed that TVDI data can be used effectively to predict crop yield on the Argentine Pampas. Depending on the agro-climatic zone, R2 values ranged from 0.68 to 0.79 for soybean crop and 0.76 to 0.81 for wheat. The RMSE values were 366 and 380 kg ha-1 for soybean and they varied between 300 and 550 kg ha-1 in the case of wheat crop. When expressed as percentages of actual yield, the RMSE values ranged from 12% to 13% for soybean and 14% to 22% for wheat. The bias values indicated that the obtained models underestimated soybean and wheat yield. Accurate crop grain yield forecast using the developed regression models was achieved one to three months before harvest. In many cases the results were better than others obtained using only a vegetation index, showing the aptitude of surface temperature and vegetation index combination to reflect the crop water condition. Finally, the analysis of a wide range of soil moisture availability allowed us to develop a generalized model of crop yield and dryness index relationship which could be applicable in other regions and crops at regional scale.

Holzman, M. E.; Rivas, R.; Piccolo, M. C.

2014-05-01

93

Estimate soil moisture using trapezoidal relationship between remotely sensed land surface temperature and vegetation index  

Directory of Open Access Journals (Sweden)

Full Text Available The trapezoidal relationship between surface temperature (Ts and vegetation index (VI was used to estimate soil moisture in the present study. An iterative algorithm is proposed to estimate the vertices of the Ts~VI trapezoid theoretically for each grid, and then WDI is calculated for each grid using MODIS remotely sensed measurements of surface temperature and enhanced vegetation index (EVI. The capability of using WDI based on Ts~VI trapezoid to estimate soil moisture is evaluated using soil moisture observations and antecedent precipitation in the Walnut Gulch Experimental Watershed (WGEW in Arizona, USA. The result shows that, Ts~VI trapezoid based WDI can well capture temporal variation in surface soil moisture, but the capability of detecting spatial variation is poor for such a semi-arid region as WGEW.

W. Wang

2010-11-01

94

An analytical algorithm for the determination of vegetation leaf area index from TRMM/TMI data  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper, an analytical algorithm for the determination of land surface vegetation Leaf Area Index (LAI) with the passive microwave remote sensing data is developed. With the developed algorithm and the Tropical Rainfall Measuring Mission/Microwave Imager (TRMM/TMI) remote sensing data collected during the Global Energy and Water Experiment (GEWEX) Asian Monsoon Experiment in Tibet (GAME/Tibet) Intensive Observation Period (IOP'98), the regional and temporal distributions of the land sur...

Wen, J.; Su, Z.

2004-01-01

95

An Assessment of Mining Activities Impact on Vegetation in Bukuru Jos Plateau State Nigeria Using Normalized Differential Vegetation Index (NDVI)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The study area has a pathetic and deplorable condition of landuse/ landcover. The vegetal cover in the area has to be removed from the activities of tin mining which consequently resulted into adverse environmental effect such as erosion. Different forms of human induced stress such as tin mining and heavy rainfall have severely degraded soils on the Jos Plateau. Such degradation problems are also caused by deforestation, inappropriate farming system, bush burning and over-grazing which are h...

Musa Haruna D.; Jiya Solomon N.

2011-01-01

96

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

DEFF Research Database (Denmark)

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.

Westergaard-Nielsen, Andreas; Lund, Magnus

2013-01-01

97

Non-Lambertian Corrected Albedo and Vegetation Index for Estimating Land Evapotranspiration in a Heterogeneous Semi-Arid Landscape  

Directory of Open Access Journals (Sweden)

Full Text Available The application of energy balance algorithms to remotely sensed imagery often fails to account for surface roughness variation with diverse land cover, resulting in poor resolution of evapotranspiration (ET variations. Furthermore, the assumption of a horizontally homogeneous Lambertian surface reflecting energy equally in all directions affects the calculations of albedo and vegetation index. The primary objective of this study is to improve the accuracy of the estimation and discrimination of ET among different land cover types in Southern New Mexico from ASTER datasets, by formulating the spatial variation of non-Lambertian reflectance using a wavelength-dependent Minnaert function.

Isabella Mariotto

2010-03-01

98

Net Radiation and Vegetation NDVI  

Science.gov (United States)

This site allows you to combine the NDVI vegetation index with Net Solar Radiation values. The Normalized Difference Vegetation Index, or NDVI, is an index of green leaf density. The higher the value, the more luxuriant the vegetation. This is but one of many animated datasets that can be combined to introduce correlations and interactions between radiant energy and the biosphere.

Observatory, Nasa E.; Nasa

99

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

2007-04-01

100

Uncertainties in estimating Normalized Difference Temperature Index from TOA radiances  

Science.gov (United States)

The widely used surface temperature/vegetation index (Ts/NDVI) triangle method provides an effective way to estimate surface turbulent energy fluxes and soil moisture. This type of method mainly relies on the Normalized Difference Temperature Index (NDTI), which is usually calculated from land surface temperature (LST). However, retrieval of LST from remote sensing data requires atmospheric correction procedures, which are often difficult and troublesome. Our study investigates the feasibility of determining NDTI using top of the atmosphere (TOA) radiances, instead of satellite-derived LST. A thorough assessment of the uncertainties in NDTI estimates for different atmospheric and surface conditions is performed. It is shown that NDTI can be estimated from TOA radiances with an accuracy of 90% if the spatial variabilities of atmospheric parameters (water vapor, effective atmospheric temperature) and surface emissivity are below 10%, 4 K and 0.05, respectively. A test study is performed using Moderate Resolution Imaging Spectroradiometer (MODIS) data over a heterogeneous area of the Poyang Lake basin of China for six consecutive image acquisitions. When the spatial variations of the surface emissivity, effective atmospheric temperature and water vapor are respectively less than 0.01, 1 K and 0.2 g cm-2, the TOA radiance-calculated NDTI value and LST-determined NDTI value are quite close with root mean square deviation (RMSD) values and biases varying from 0.033 to 0.051 and from -0.004 to 0.014. The high coefficient of determination (R2) values, ranging from 0.904 to 0.939, indicated that the use of TOA radiances appears to be adequate for calculating NDTI in these studies. Overall, the proposed algorithm requires less a prior information on the atmospheric state while providing NDTI estimates at a similar level of accuracy than obtained using atmospherically corrected LST data products. It therefore provides a useful alternative for determining NDTI from satellite data.

peng, jian; liu, yuanbo; loew, alexander

2013-04-01

 
 
 
 
101

Estimation of soil moisture using trapezoidal relationship between remotely sensed land surface temperature and vegetation index  

Directory of Open Access Journals (Sweden)

Full Text Available The trapezoidal relationship between land surface temperature (Ts and Vegetation Index (VI was used to estimate soil moisture in the present study. An iterative algorithm is proposed to estimate the vertices of the Ts ~ VI trapezoid theoretically for each pixel, and then Water Deficit Index (WDI is calculated based on the Ts ~ VI trapezoid using MODIS remotely sensed measurements of surface temperature and enhanced vegetation index (EVI. The capability of using WDI based on Ts ~ VI trapezoid to estimate soil moisture is evaluated using soil moisture observations and antecedent precipitation in the Walnut Gulch Experimental Watershed (WGEW in Arizona, USA. The result shows that, the Ts ~ VI trapezoid based WDI can capture temporal variation in surface soil moisture well, but the capability of detecting spatial variation is poor for such a semi-arid region as WGEW.

W. Wang

2011-05-01

102

Estimating the Maximal Light Use Efficiency for Different Vegetation through the CASA Model Combined with Time-Series Remote Sensing Data and Ground Measurements  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Maximal light use efficiency (LUE) is an important ecological index of a vegetation essential attribute, and a key parameter of the LUE-based model for estimating large-scale vegetation productivity by remote sensing technology. However, although currently used in different models there still exists extensive controversy. This paper takes the Zoige Plateau in China as a case area to develop a new approach for estimating the maximal LUEs for different vegetation. Based on an existing land cove...

Ainong Li; Jinhu Bian; Guangbin Lei; Chengquan Huang

2012-01-01

103

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)

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.

Hirokazu Yamamoto

2008-04-01

104

Exposure to vegetable variety in infants weaned at different ages.  

Science.gov (United States)

The aim of the current study was to examine the effectiveness of different vegetable exposure methods (variety versus single taste) over a 9 day period in two groups of infants; those introduced to solids prior to the age of 5.5 months, and those introduced after 5.5 months. Sixty parent-infant dyads were recruited in South Birmingham, UK. Infants' acceptance of a novel vegetable (pea puree) was measured after a 9 day exposure period in the infants a week after they were first introduced to solid foods. During the exposure period half of each age group was given carrot every day, and the other half was given a variety pack of courgette, parsnip and sweet potato. A baseline measurement of the infants' acceptance of a vegetable (carrot) was taken prior to the exposure period. There was no difference between the groups in consumption of the baseline vegetable (carrot). There were no main effects of exposure group or age group on consumption of pea after the exposure period. There was, however, an interaction between the age of introduction and exposure group on consumption of the new vegetable (pea). In particular, infants weaned at 6 months in the single taste group ate significantly less pea puree than those in the variety group. These findings suggest that infants, who are weaned at 6 months or later, may benefit from being weaned onto a variety of tastes rapidly to ensure adequate exposure to taste. This study constitutes some of the first evidence to suggest that there may be a sensitive period for the acceptance of tastes between the ages of 4 and 6 months. PMID:24685457

Coulthard, Helen; Harris, Gillian; Fogel, Anna

2014-07-01

105

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

Science.gov (United States)

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.

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

2013-12-01

106

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

Science.gov (United States)

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

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

2014-02-01

107

Determination index of compatible vegetable species with the lines of electric power transmission  

International Nuclear Information System (INIS)

With the purpose of designing methods to clearly identify which plant species generate electrical ground discharges in energy transmission line service corridors and thus avoid the frequent pruning of all Vegetation present in the corridors this study proposes and evaluates compatibility index of plant species with transmission lines, based on six variables: maximum height, growth form, ecological group, life zone, and abundance and frequency of each species. This index was tested in 20 plots of information was collected on all vascular plans present yielding 2147 individuals belonging to 485 species and 105 families, the most discriminating variables in the model were life zone and ecological group, based upon an analysis of principal components. This index applied to the 147 fully identified species with DBH = 2,5 cm showed that Cecropia peltata and Jacaranda copaia were the most problematic species for service lines. Furthermore, a catalogue was developed containing general information and a photographic record of some of the species considered as compatible as a reference for use during maintenance work

2004-01-01

108

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)

2013-01-01

109

Integración del Índice de Vegetación de la Diferencia Normalizada (NDVI y del Ciclo Fenológico de Maíz para Estimar el Rendimiento a Escala Departamental en Córdoba, Argentina Normalized Difference Vegetation Index (NDVI and Phenological Data Integration to Estimate County Yield of Corn in Córdoba, Argentina  

Directory of Open Access Journals (Sweden)

Full Text Available La integración de datos radiométricos con información agroclimática puede resultar en mejores procedimientos para evaluar el estado y evolución de los cultivos. En este trabajo, datos del calendario fenológico del cultivo de maíz (Zea mays L., estimados a partir de procedimientos de sumas térmicas, fueron integrados con registros del Indice de Vegetación de la Diferencia Normalizada (NDVI de cobertura global del sistema Radiómetro Avanzado de Muy Alta Resolución de la Administración Nacional del Océano y la Atmósfera de los Estados Unidos (NOAA-AVHRR, con los siguientes objetivos: i evaluar la relación entre el NDVI y el rendimiento de maíz en distintas etapas del ciclo del cultivo; ii analizar la influencia de la fecha de siembra, y iii desarrollar un modelo de pronóstico del rendimiento de maíz a escala departamental. Los valores acumulados de NDVI presentaron una asociación positiva con el rendimiento de maíz, variable de acuerdo a la etapa de desarrollo y la fecha de siembra consideradas. Durante la etapa reproductiva, el NDVI expresó una elevada asociación con el rendimiento en cualquier fecha de siembra eventual, alcanzando valores de correlación significativos (P Integration of satellite data with agroclimatic information can result in better procedures to evaluate the state and evolution of grain crops. In this work, phenologic calendar of corn (Zea mays L. crop based on growing-degree days procedures was integrated with Normalized Difference Vegetation Index (NDVI estimations from global coverage of National Oceanic and Atmospheric Administration-Advanced Very High Resolution Radiometer (NOAA-AVHRR system. The main objectives were: i to evaluate the relationship between NDVI and corn yield in different stages of crop cycle; ii to analyze the influence of sowing date, and iii to develop a predictive model of county (departmental corn yield using satellite and ground data. The NDVI values accumulated in different corn phenologic stages showed a positive association with yield, and this relationship was modified in function of sowing date. The NDVI value during the reproductive stage, for any sowing date, always expressed a high association with corn yield, reaching significant correlation values (P < 0.05 in all cases, and even higher (P < 0.01 for some evaluated dates. The higher sensitivity showed by the reproductive stage confirms that it is a critical period. Starting from this information, a prediction model was obtained that explains around 80% of corn yield variability of Marcos Juárez Department in Córdoba Province, Argentina.

Antonio de la Casa

2007-12-01

110

Estimation of canopy parameters for inhomogeneous vegetation canopies from reflectance data. II - Estimation of leaf area index and percentage of ground cover for row canopies  

Science.gov (United States)

The canopy reflectance (CR) model for row-planted vegetation proposed earlier has been tested for soybean canopies in three different stages of growth and for corn canopies at early and full growth stages. The model fits the field-measured bidirectional CR data quite well. It is shown that, by inverting this model, one could estimate the leaf area index as well as the percentage of ground cover quite accurately from measured canopy reflectances.

Goel, N. S.; Grier, T.

1986-01-01

111

The Infrared Difference Dust Index: Past, Present and Future  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The Infrared Difference Dust Index (IDDI) [Legrand et al, 2001] is a Meteosat-derived thermal-infrared (TIR) index dedicated to remote sensing of desert aerosol over land (based on the former Meteosat First Generation (MFG) series). The IDDI product proves to be effective in studies of dust source location and seasonal activity [Brooks and Legrand, 2000; Léon and Legrand, 2003; Deepshikha et al, 2003a; b], in the physics of dust emission with respect to the surface properties [Chomette et al...

Legrand, Michel; Chiapello, Isabelle; Franc?ois, Philippe; Nakes, Mohamed T.

2010-01-01

112

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)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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.

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

113

Empirical Regression Models for Estimating Multiyear Leaf Area Index of Rice from Several Vegetation Indices at the Field Scale  

Directory of Open Access Journals (Sweden)

Full Text Available Leaf area index (LAI is among the most important variables for monitoring crop growth and estimating grain yield. Previous reports have shown that LAI derived from remote sensing data can be effectively applied in crop growth simulation models for improving the accuracy of grain yield estimation. Therefore, precise estimation of LAI from remote sensing data is expected to be useful for global monitoring of crop growth. In this study, as a preliminary step toward application at the regional and global scale, the suitability of several vegetation indices for estimating multi-year LAI were validated against field survey data. In particular, the performance of a vegetation index known as time-series index of plant structure (TIPS, which was developed by the authors, was evaluated by comparison with other well-known vegetation indices. The estimated equation derived from the relationship between TIPS and LAI was more accurate at estimating LAI than were equations derived from other vegetation indices. Although further research is required to demonstrate the effectiveness of TIPS, this study indicates that TIPS has the potential to provide accurate estimates for multi-year LAI at the field scale.

Masayasu Maki

2014-05-01

114

Scaling the h-index for different scientific ISI fields  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We propose a simple way to put in a common scale the h values of researchers working in different scientific ISI fields, so that the previsible misuse of this index for inter-areas comparison might be prevented, or at least, alleviated.

Iglesias, Juan E.; Pecharroman, Carlos

2006-01-01

115

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.

2011-10-01

116

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

117

Comparing forest measurements from tree rings and a space-based index of vegetation activity in Siberia  

International Nuclear Information System (INIS)

Different methods have been developed for measuring carbon stocks and fluxes in the northern high latitudes, ranging from intensively measured small plots to space-based methods that use reflectance data to drive production efficiency models. The field of dendroecology has used samples of tree growth from radial increments to quantify long-term variability in ecosystem productivity, but these have very limited spatial domains. Since the cambium material in tree cores is itself a product of photosynthesis in the canopy, it would be ideal to link these two approaches. We examine the associations between the normalized differenced vegetation index (NDVI) and tree growth using 19 pairs of tree-ring widths (TRW) and maximum latewood density (MXD) across much of Siberia. We find consistent correlations between NDVI and both measures of tree growth and no systematic difference between MXD and TRW. At the regional level we note strong correspondence between the first principal component of tree growth and NDVI for MXD and TRW in a temperature-limited bioregion, indicating that canopy reflectance and cambial production are broadly linked. Using a network of 21 TRW chronologies from south of Lake Baikal, we find a similarly strong regional correspondence with NDVI in a markedly drier region. We show that tree growth is dominated by variation at decadal and multidecadal time periods, which the satellite record is incapable of recording given its relatively short record. (letter)

2013-01-01

118

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)

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 content (TCab), and total vegetation water content (VWC). A numerical optimization method was employed for the inversion of a canopy reflectance model using Terra and Aqua MODIS multi-spectral, multi-temporal, and multi-angle reflectance observations to aid the determination of vegetation-specific physiological and structural canopy parameters. Land cover and site-specific inversion modeling was applied to a restricted number of pixels to build multiple species- and environmentally dependent formulations relating the three biophysical properties of interest to a number of selected simpler spectral vegetation indices (VI). While inversions generally are computationally slow, the coupling with the simple and computationally efficient VI approach makes the combined retrieval scheme for LAI, TCab, and VWC suitable for large-scale mapping operations. In order to facilitate application of the canopy reflectance model to heterogeneous forested areas, a simple correction scheme was elaborated, which was found to improve forest LAI predictions significantly and also provided more realistic values of leaf chlorophyll contents. The inversion scheme was designed to enable biophysical parameter retrievals for land cover classes characterized by contrasting canopy architectures, leaf inclination angles, and leaf biochemical constituents without utilizing calibration measurements. Preliminary LAI validation results for the Island of Zealand, Denmark (57°N, 12°E) provided confidence in the approach with root mean square (RMS) deviations between estimates and in-situ measurements of 0.62, 0.46, and 0.63 for barley, wheat, and deciduous forest sites, respectively. Despite the independence on site-specific in-situ measurements, the RMS deviations of the automated approach are in the same range as those established in other studies employing field-based empirical calibration. Being completely automated and image-based and independent on extensive and impractical surface measurements, the retrieval scheme has potential for operational use and can quite easily be implemented for other regions. More validation studies are needed to evaluate the usefulness and limitations of the approach for other environments and species compositions.

Houborg, Rasmus Møller; Søgaard, Henrik

2007-01-01

119

Estimation of Cholesterol Level in Different Brands of Vegetable Oils  

Digital Repository Infrastructure Vision for European Research (DRIVER)

An analysis of twenty one assorted brands of vegetable oils in Lagos Metropolis Nigeria, reveals varying levels of cholesterol content. Cholesterol was found to be present in most of the oil brands sampled using three standard methods. Cholesterol was detected in seventeen of the vegetable oil brands with concentration of less than 1 mg/ml while seven of the oil brands had cholesterol concentrations ranging between 1-4 mg/ml. Low iodine values were obtained in four of the vegetable oil ...

Okpuzor, J.; Okochi, V. I.; Ogbunugafor, H. A.; Ogbonnia, S.; Fagbayi, T.; Obidiegwu, C.

2009-01-01

120

Effect of riparian vegetation on diatom assemblages in headwater streams under different land uses.  

Science.gov (United States)

Differences in the structure of diatom assemblages in headwaters with contrasting shading conditions and different land use in the buffer zone and upper catchment were studied in order to evaluate the influence of the lack of riparian vegetation on the biofilm. The objective was to ascertain whether a riparian buffer can mitigate the negative influence of human induced disturbance and pollution on diatom assemblages in headwaters. Four streams were selected in order to maximize the differences in the land cover and minimize other environmental gradients. Multivariate statistics, different comparative and permutation tests and correlations were applied to compare the diatom assemblages, the Specific Polluosensitivity Index (IPS) and the diatom ecological guilds (low profile, high profile and motile) among the sites studied and to evaluate their responses to disturbances. The analysis showed that low profile diatoms typically dominated in forested headwaters with limited resources, whilst assemblages at impacted sites showed a wider range of growth forms. In unimpacted streams, the diatom assemblages were influenced by temperature, pH, conductivity and calcium, as usually reported for oligotrophic streams with high natural disturbance due to fast current and shading. In both shaded and unshaded impacted streams, the importance of nutrients and land use disturbance, especially urbanization, prevailed. This trend was also reflected by the IPS index that showed consistently lower values at impacted sites, correlating most significantly with nutrients. The diatom species composition as well as diatom guilds at impacted sites were similar, regardless of the presence or absence of riparian vegetation, and were significantly influenced by seasonal changes. Our results indicate that diatoms react sensitively to alterations of the water environment in headwaters, induced by anthropogenic activities, and these impacts are not buffered by an intact riparian zone. Diatoms closely reflected land use practices in the upper catchment regardless of the buffer zone status. PMID:23820576

Hlúbiková, Daša; Novais, Maria Helena; Dohet, Alain; Hoffmann, Lucien; Ector, Luc

2014-03-15

 
 
 
 
121

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)

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.

Kellogg, Christopher H.; Zhou, Xiaobing

2014-10-01

122

Effect of three different nitrogen fertilizers on several vegetable crops  

Directory of Open Access Journals (Sweden)

Full Text Available Applications of three different sources of N fertilizers (urea, compost from slaughter house and chicken manure compost on vegetable crops (tomato, okra and spinach were conducted in the green house of Research Institute for Food Crop Biotechnology, Bogor from August of 1999 to April of 2000. Treatments consisted of: (i without fertilizer, (ii 5 g N/pot of urea, (iii 10 g N/pot of slaughter house compost, (iv 10 g N/pot of chicken manure compost, (v 5 g N/pot of urea + 10 g N/pot of slaughter house compost, and (vi 5 g N/pot of urea + 10 g N/pot of chicken manure compost. Completely Randomized Design with 3 replicates was used in the experiments. In the first experiment, tomatoes were planted in the first season, following by okra in the second season. In the second experiment, spinach was planted for 6 times. Urea and compost were applied only once at the beginning of the experiment. Results of the experiments showed that for the first experiment

WIDIATI HADI ADIL

2006-01-01

123

Vitamin E and Beta Carotene Composition in Four Different Vegetable Oils  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ?-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:<...

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

2011-01-01

124

Evaluation of Digital Hemispherical Photography and Plant Canopy Analyzer for Measuring Vegetation Area Index of Orange Orchards  

Directory of Open Access Journals (Sweden)

Full Text Available This study presents the results of an evaluation of two indirect methods (Plant Canopy Analyzer (PCA and hemispherical photographs for measuring Vegetation Area Index (VAI of two orange orchards, differing by their ground fraction cover (fc. The evaluation is based on reference data obtained by destructive measurements on limited samples, which allow to calibrate and validate an exponential relationship between the diameter of branches and associated areas of leaves (R2 = 0.99. The obtained results show that the two indirect methods underestimate the reference values of VAI. For the PCA device, the best estimates of VAI are obtained using the five rings for high fc (fc = 0.7 and using only four rings for low fc (fc = 0.3. For both case, the hemispherical photographs give accurate estimates of VAI: the relative errors are about 11 and 14% for high and low fc, respectively. Alternatively, a simple method consisting of calculating VAI as the weighted average of the maximum (VAImax, below the tree and minimum (VAImin, at the center of four trees values using fc as a weighting factor, was successfully tested (R2 = 0.90. For both indirect methods, the tree volumes are well estimated with comparison to the values calculated assuming an ellipsoidal form.

S. Khabba

2009-01-01

125

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

DEFF Research Database (Denmark)

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, λE, (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 λE 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

Garcia, Monica; Sandholt, Inge

2014-01-01

126

Vegetative growth and yield of strawberry under irrigation and soil mulches for different cultivation environments  

Directory of Open Access Journals (Sweden)

Full Text Available The vegetative growth and yield of strawberry in relation to irrigation levels and soil mulches are still not well known, mainly for different environmental conditions. Two experiments were carried out in Atibaia, SP, Brazil, during 1995, one in a protected environment and the other in an open field, to evaluate the cultivar Campinas IAC-2712, under different irrigation levels and soil mulches (black and clear polyethylene. Three water potential levels in the soil were used in order to define irrigation time, corresponding to -0.010 (N1, -0.035 (N2, and -0.070 (N3 MPa, measured through tensiometers installed at the 10 cm depth. A 2 x 3 factorial arrangement was adopted, as randomized complete block, with 5 replicates. In the protected cultivation, the irrigation levels of -0.010 and -0.035 MPa and the clear plastic mulch favored the vegetative growth, evaluated through plant height, maximum horizontal dimension of the plant, leaf area index, as well as by total marketable fruit yield and its components (mean number and weight of fruits per plant. In the open field cultivation, no effect of treatments due to rainfall were observed.

Pires Regina Célia de Matos

2006-01-01

127

Vitamin E and Beta Carotene Composition in Four Different Vegetable Oils  

Directory of Open Access Journals (Sweden)

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 ?-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 ?-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 ?-carotene.

Ab. G.M. Top

2011-01-01

128

Estimation of Cholesterol Level in Different Brands of Vegetable Oils  

Directory of Open Access Journals (Sweden)

Full Text Available An analysis of twenty one assorted brands of vegetable oils in Lagos Metropolis Nigeria, reveals varying levels of cholesterol content. Cholesterol was found to be present in most of the oil brands sampled using three standard methods. Cholesterol was detected in seventeen of the vegetable oil brands with concentration of less than 1 mg/ml while seven of the oil brands had cholesterol concentrations ranging between 1-4 mg/ml. Low iodine values were obtained in four of the vegetable oil brands and three of them had high acid values. High performance liquid chromatography (HPLC confirmed the presence of cholesterol at varying concentrations in all the oil brands and gave the lowest detectable cholesterol values in all the oil brands. The Laser brand made from rapeseed had the highest cholesterol concentration of 3.2 mg/ml while Grand brand made from groundnuts had the least concentration (0.12 mg/ml of cholesterol using HPLC analysis. Leibermann-Burchard method showed that Gino brand from palm kernel had the least concentration of cholesterol (3.86 mg/ml ±0.032 and the highest concentration of 3.996 mg/ml ±0.0404 was obtained in Sesame seed oil brand. This report is important in view of health implications of cholesterol in our diets. Consequently, we have been able to show that there is no cholesterol free oil in the market as shown on the vegetable oil brand labels. Therefore, companies producing and marketing vegetable oils are enjoined to desist from misleading the public by labeling their products as “cholesterol free”. They should indicate the amount of cholesterol present in the vegetable oil, no matter how small the quantity may be.

J. Okpuzor

2009-01-01

129

Study of a Vegetation Index Based on HJ CCD Data's top-of-atmosphere reflectance and FPAR Inversion  

Science.gov (United States)

The Fraction of Photosynthetically Active Radiation (FPAR)absorbed by plant canopies is a key parameter for monitoring crop condition and estimating crop yield. In general, it is necessary to obtain Top of Canopy (TOC) reflectance from optical remote sensing data in digital number through atmospheric correction procedures before retrieving FPAR. However, there are a few of uncertainties that existe in the process of atmosphere correction and reduced the quality of TOC. This paper presents a vegetation index based on Top-of-Atmosphere (TOA) reflectance derived from HJ-1 CCD satellite for estimating direct crop FPAR. The vegetation index (HJVI) was designed based on the simulated results of a canopy-atmosphere radiative transfer model, including TOA reflectance and corresponded FPAR. The HJVI had taken the advantages of information in the green, the red and the near-infrared spectral domainswith with a aim of reducing the atmospheric effect and enhancing the sensitive to green vegetation. The HJVI was used to estimate soybean FPAR directly and validated using field measurements. The result indicated that the inversion algorithm produced a good relationship between the prediction and measurement (R2 = 0.546, RMSE = 0.083) and the HJVI showed high potential for estimating FPAR based on the HJ-1 TOA reflectance directly.

Dong, Taifeng; Wu, Bingfang; Meng, Jihua

2014-03-01

130

Indexed  

CERN Document Server

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.

Hagy, Jessica

2008-01-01

131

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

Science.gov (United States)

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.

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

2013-05-01

132

RICH with multiple aerogel layers of different refractive index  

International Nuclear Information System (INIS)

A proximity focusing ring imaging Cherenkov detector with multiple aerogel radiator layers is studied. In situations where limited space is available and a compact RICH detector is required, the use of a nonhomogeneous, multiple refractive index radiator offers a possibility for improving the resolution. Experimental investigations of the relevant parameters, i.e. single photon Cherenkov angle uncertainty and number of detected photons per ring, are presented for different aerogel radiator configurations. The results are promising and appear to satisfy the requirements for the forthcoming upgrade of the particle identification system of the Belle detector

2005-11-11

133

RICH with multiple aerogel layers of different refractive index  

Science.gov (United States)

A proximity focusing ring imaging Cherenkov detector with multiple aerogel radiator layers is studied. In situations where limited space is available and a compact RICH detector is required, the use of a nonhomogeneous, multiple refractive index radiator offers a possibility for improving the resolution. Experimental investigations of the relevant parameters, i.e. single photon Cherenkov angle uncertainty and number of detected photons per ring, are presented for different aerogel radiator configurations. The results are promising and appear to satisfy the requirements for the forthcoming upgrade of the particle identification system of the Belle detector.

Korpar, S.; Adachi, I.; Fratina, S.; Fukushima, T.; Gorišek, A.; Iijima, T.; Kawai, H.; Konishi, H.; Kozakai, Y.; Križan, P.; Matsumoto, T.; Mazuka, Y.; Nishida, S.; Ogawa, S.; Ohtake, S.; Pestotnik, R.; Saitoh, S.; Seki, T.; Stanovnik, A.; Sumiyoshi, T.; Uchida, Y.; Unno, Y.; Yamamoto, S.

2005-11-01

134

Diseño de índices espectrales de la vegetación usando curvas iso-suelo / Design of spectral vegetation indexes using iso-soil curves  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: Spanish Abstract in spanish El diseño de índices espectrales de la vegetación (IV) basados en las líneas iso-índice de área foliar (misma cantidad de vegetación y propiedades ópticas diferentes de los suelos debajo de la vegetación) en el ancho de banda del rojo (R) e infrarrojo cercano (IRC) del espectro electromagnético, res [...] ulta complejo por el patrón expo-lineal con cambio de pendiente, entre los parámetros que definen estas líneas. Una alternativa de diseño es considerar los patrones de las curvas iso-suelo (mismo suelo y cantidad variable de vegetación), usando el IRC como banda de saturación más lenta posible. El índice IVIS (IV basado en las curvas iso-suelo) introducido permite este tipo de aproximación, al usar una transformación del espacio de R para hacerlo coincidir con la línea del suelo y una estructura matemática similar a índices uni-banda espectral. La validación de IVIS usando simulaciones radiativas y de experimentos con cultivos generó resultados aceptables, particularmente con una óptica de minimización del efecto del suelo en escala píxel por píxel. La transformación de IVIS permite la parametrización de la curva de crecimiento en formato lineal, simple de implementar en términos algorítmicos. Abstract in english The design of spectral vegetation indexes (VI) based on the lines iso-leaf area index (same amount of vegetation and different optical properties of the soils under the vegetation) in two bands of the electromagnetic spectrum, the red (R) and near-infrared (NIR), is complicated because of the expoli [...] near pattern with change of slope, among the parameters that define these lines. An alternative design is to consider the patterns of iso-soil curves (same soil, and varying amounts of vegetation), using the NIR as a saturation band as slow as possible. The introduced index ISVI (VI based on the iso-soil curves) allows this type of approach, by using a transformation of the space of R to make it coincide with the soil line and a mathematical structure similar to uni-band spectral indexes. ISVI validation using radiative simulations and crop experiments produced acceptable results, particularly with a perspective of minimizing the soil effect at píxel by píxel scale. The transformation of the ISVI allows parameterization of the growth curve in a linear format, simple to implement in algorithmic terms.

Fernando, Paz-Pellat; Marisol, Reyes; Edgardo, Mediano.

135

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

Science.gov (United States)

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.

Meulebroeck, Wendy; Thienpont, Hugo

2012-05-01

136

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

Energy Technology Data Exchange (ETDEWEB)

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)

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

137

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

International Nuclear Information System (INIS)

The height of the dry deposition of gaseous elemental 131I 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 131I 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 131I 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 131I. (author)

2004-09-06

138

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  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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-...

Bárbara Teruel; Theo Kieckbusch; Luis Cortez

2004-01-01

139

Experiments of hydraulics mechanics through different arrangement of submerged bending vegetation  

Science.gov (United States)

Laboratory experiments are used to explore the effect of different arrangement of submerged bending vegetation in the fixed bed on flow field around vegetation and area downstream. The two simulated bending vegetation were composed of pipe curved to 90 degree for stems and P.P.C films for blades. The two bending vegetation were arranged in alignment and paralleled with flow direction. The test arrangement was distinguished by different overlap rate of vegetation. Overlap rate of vegetation were defined that percentage of blades of bending vegetation overlap the other one. Overlap rate is greater than zero and it means that vegetation overlap the other one. On the other hand, overlap rate is smaller than zero and it means that two plants were separated in percentage of total length of vegetation The experiments were carried out 10 test in forms of overlap rate of vegetation (50%, 25%, 0%,-25%,-50%) by blades of 20cm and 25cm.Velocity and turbulence intensity around the vegetation (u, v, w and urms, vrms, wrms) were acquired by Ultrasound Velocity Profiler (UVP). Furthermore, to elaborate variation of the flow field, the swinging motion of vegetation was recorded by digital camera. Three arrangement types (overlapped, continuous and isolated) were concluded from the 10 tests. In case of isolated vegetation, it could be observed that there was a better effect on slowing flow velocity in x direction in case of the tests with -25% overlap rate due to a discontinuous shear layer between two plants which induced wake interference. It also showed that turbulence intensity was significant between two plants. Two plants disturbed rarely each other in the tests of isolated vegetation with -50% overlap rate .Flow was disturbed by swinging of blades only and returned to stable quickly. In 25% and 50% tests, two plants were overlapped and their behavior was similar to a longer blades plant. Its blades swinging were not obvious result as low effect on slowing velocity in x direction. It means that the characteristic of overlapped vegetation is good for stabilizing the flow field. The research helped to realize influence between two plants on flow field in order to apply river system management strategies.

Chen, Ye-Hong; Chen, Su Chun

2014-05-01

140

Composite spectra of quasars with different UV spectral index  

Science.gov (United States)

The composite spectra of quasars are widely used as templates for redshift determination, as well as for measurements of the mean transmission (the mean ratio of observed and emitted flux within the Ly? forest part of quasar spectra) in Ly?-forest studies, and for investigation of general spectral properties of quasars. Possibility of composite spectra utilization in these fields is related to remarkable similarity of quasar spectra in UV-optical range. But despite of general similarity in spectral shapes, they differ in several parameters, one of which is the spectral index. In this paper, we study the possible effects related to neglect of this difference. We compiled 16 composite spectra from subsamples of individual Sloan Digital Sky Survey (SDSS) DR7 quasar spectra with different spectral indices ?? within the wavelength range 1270-1480 Å. Using them we show that (i) the uncertainties of redshifts measured for a test sample of high signal-to-noise ratio quasar spectra using these composites as templates appear to be 1.5 times smaller than of those calculated with a traditional template, compiled from spectra with different ??; (ii) the difference in ?? in individual spectra used for compilation of composites can yield the mean transmission uncertainty up to 20 per cent; (iii) a number of emission lines indistinguishable in ordinary composites, but seen in individual high-resolution spectra, can be detected in such composites. It is also shown that there is no dependence of ?? on quasar luminosity in SDSS u, g, r and i bands, and monochromatic luminosity at 1450 Å.

Ivashchenko, G.; Sergijenko, O.; Torbaniuk, O.

2014-02-01

 
 
 
 
141

Differences in resistance of three subtropical vegetation types to experimental trampling.  

Science.gov (United States)

Experimental trampling trials using a standardized methodology were undertaken in 10 replicate blocks in three vegetation types in an urban reserve in the subtropics of Australia. In each block different intensities of trampling (controls, 10, 25, 50, 100, 150, 200, 250, 300, 400 and 500 passes) were applied, and vegetation parameters were measured pre-trampling, immediately after trampling and 2 weeks later. A Fern understorey had low resistance to trampling intensity, with reductions in relative vegetation height and cover with as few as 10 passes. A Tussock grass understorey showed moderate resistance with reduction in height at 25 passes and cover at 50 passes. A Disturbed grassland dominated by lawn grasses had the highest resistance, with reductions in vegetation height at 100 passes, but cover was affected by as few as 10 passes. The resistance indices (number of passes required to reduce vegetation cover by 50%) of three vegetation types were 210, 360 and 860 passes, respectively. When these values were compared with those for 52 other vegetation types considerable variation was found within life forms, climatic zones and vegetation types indicating that the response of a specific community may not always be predictable. PMID:18799252

Hill, Rachel; Pickering, Catherine

2009-02-01

142

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

Directory of Open Access Journals (Sweden)

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.

Mingliang Che

2014-06-01

143

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Breunig, Fa?bio M.; Galva?o, Le?nio S.; Formaggio, Anto?nio R.; Epiphanio, Jose? C. N.

2012-01-01

144

Wildfire, vegetation change, and carbon: the effect of different projected climate futures on vegetation in the western United States  

Science.gov (United States)

The dynamic vegetation model MC2 simulates vegetation distribution, biogeochemical cycling, and wildfire in a highly interactive manner. It has been widely used at multiple scales (30arc sec to .5 deg) to simulate potential vegetation shifts, C fluxes and dynamic wildfires in national parks, individual states, across the nation and the continent as well as globally for a handful of climate change scenarios. In this new project, the model is using a suite of climate futures from the Coupled Model Intercomparison Project (CMIP5) downscaled using a fairly new statistical downscaling approach, Multivariate Adaptive Constructed Analogs, over the western US. The model is run on the NASA Earth Exchange (NEX) platform at 4km resolution since it requires the large-scale computing power to produce results for > 30 climate futures in a reasonable time frame. Early results show large shifts in vegetation towards warmer types (e.g. temperate to subtropical forest types, warm subtropical grasslands replacing cool temperate grasslands) and an expansion of forest types enhanced by a moderate CO2 effect on water use efficiency and production when water availability declines. While all climate models project warmer conditions, they differ in their projections of the seasonality and magnitude of rainfall. The model is sensitive to the water available for plant production and soil organic matter decomposition, fuel-build up and wildfire occurrence. Complex interactions of climate and disturbance drive the large changes the model is simulating with much geographic patchiness due to soil types as well as temporal variability due to changes in rainfall seasonality.

Sheehan, T.; Bachelet, D. M.; Ferschweiler, K.; Abatzoglou, J. T.; Hegewisch, K.

2013-12-01

145

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Nagler, Pamela L.; Kiyomi Morino; Scott Murray, R.; John Osterberg; Glenn, Edward P.

2009-01-01

146

Vegetative Growth of Four Strains of Hericium erinaceus Collected from Different Habitats.  

Science.gov (United States)

Vegetative growth of four different strains of Hericium erinaceus was observed. The temperature suitable for optimal mycelial growth was determined to be 25?, with growth observed in the extend temperature range of 20~30?. The different strains of this mushroom showed distinct pH requirements for their optimum vegetative growth, with the most favorable growth observed at pH 6. Considering vegetative mycelial growth, PDA, YM, Hennerberg, Hamada, and Glucose peptone were the most favorable media, and Czapek Dox, Hoppkins, Glucose tryptone, and Lilly were the most unfavorable media for these mushroom strains. With the exception of lactose, most of the carbon sources assayed demonstrated favorable vegetative growth of H. erinaceus. For mycelial growth, the most suitable nitrogen source was alanine and the most unsuitable was histidine. Oak sawdust medium supplemented with 10~20% rice bran was the best for mycelial growth of the mushroom. PMID:23990739

Imtiaj, Ahmed; Jayasinghe, Chandana; Lee, Geon Woo; Shim, Mi Ja; Rho, Hyun-Su; Lee, Hyun Sook; Hur, Hyun; Lee, Min Woong; Lee, U-Youn; Lee, Tae-Soo

2008-06-01

147

Response of different crop and vegetable cultivars to UV-B-irradiance: preliminary results  

International Nuclear Information System (INIS)

The experiments which are reported here were performed in continuation of the work of ESSER (1979, 1980) who conducted field experiments aimed at investigating the influence of increased UV-B-radiation on crop and vegetable plants of various species. In contrast to these investigations the work of this third phase concentrates on cultivar-specific differences between selected crop and vegetable cultivars. (orig./AJ)

1982-06-01

148

Plant biodiversity and vegetation structure in traditional cocoa forest gardens in southern Cameroon under different management  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Floristic surveys were performed in 17 traditional cocoa forest gardens under different management regimes in the humid forest area of southern Cameroon, to assess the impact of intensification on plant biodiversity. This impact was evaluated by analyzing species richness, vegetation structure, carbon sequestration and above ground biomass. We hypothesize that: (a) plant (tree and herbs) species richness is negatively correlated to management intensity and (b) vegetational density predictably...

Bisseleua, D. Herve? B.; Vidal, Stefan

2007-01-01

149

Territorial Differences of Human Development Index in Romania  

Directory of Open Access Journals (Sweden)

Full Text Available The measuring of human capital, human development from both a quantitative and a qualitative point of view is difficult, the problem being further complicated if we consider regional and territorial approaches as well. At an international level, the Human Development Index is usually used for measuring and comparing these issues. This index addresses the most complex level of development of a region through the aggregation of the three indices from demographic (life expectancy at birth, social (education level and the economic sphere (GDP per capita with which we can have a much more complex picture about living standards of the population as well as the development level of a country. Because the applicability of this index has caused serious debates since its introduction, this study also focuses on selecting the right indicators for measuring human development.

IBOLYA KURKÓ

2011-01-01

150

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)

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.

Isabel Cristina Fialho Harder

2006-04-01

151

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  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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 pei [...] to) 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. Abstract in english 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 ca [...] lculated 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.

Harder, Isabel Cristina Fialho; Ribeiro, Roberval de Cássia Salvador; Tavares, Armando Reis.

152

Evaluating and predicting the oxidative stability of vegetable oils with different fatty acid compositions.  

Science.gov (United States)

The aim of this research was to evaluate the oxidative stabilities and qualities of different vegetable oils (almond, blend 1-8, camellia, corn, palm, peanut, rapeseed, sesame, soybean, sunflower, and zanthoxylum oil) based on peroxide value (PV), vitamin E content, free fatty acid, and fatty acid composition. The vegetable oils with different initial fatty acid compositions were studied under accelerated oxidation condition. It showed that PV and n-3 polyunsaturated fatty acid (PUFA) changed significantly during 21 d accelerated oxidation storage. Based on the changes of PV and fatty acid composition during the oxidation process, mathematical models were hypothesized and the models were simulated by Matlab to generate the proposed equations. These equations were established on the basis of the different PUFA contents as 10% to 28%, 28% to 46%, and 46% to 64%, respectively. The simulated models were proven to be validated and valuable for assessing the degree of oxidation and predicting the shelf life of vegetable oils. PMID:23527564

Li, Hongyan; Fan, Ya-wei; Li, Jing; Tang, Liang; Hu, Jiang-ning; Deng, Ze-yuan

2013-04-01

153

Antioxidant Contents (Vitamin C of Raw and Blanched Different Fresh Vegetable Samples  

Directory of Open Access Journals (Sweden)

Full Text Available The study was aimed to determine the antioxidant contents and the effect of different blanching times (5 min, 10 min, 15 min and 20 min on antioxidant contents of three different selected fresh vegetables. Three different types of vegeta- ble were used namely Amaranthus specie locally known as spinach, namely “tete”, (Celosia argentea, soko, (Solonum nodifiorum and odu, (Telfeira occidentalis were analyzed for their antioxidant contents. The analysis revealed that raw vegetables have the highest amount of antioxidant contents. Telferia occidentalis had the highest antioxidant content followed by Solonum nodifiorum. It was observed that blanching time had an adverse effect on the antioxidant contents of the blanched vegetables. The antioxidant contents of tete, soko and odu were significantly decreased (p < 0.05 after blanching.

Isaac B. Ariyo

2012-01-01

154

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

Science.gov (United States)

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 %.

Zhang, Xiaoyang; Tan, Bin; Yu, Yunyue

2014-05-01

155

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

Science.gov (United States)

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

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

2013-11-01

156

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)

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.

Michelle Cristina Araujo Picoli

2009-09-01

157

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2010-01-01

158

Integrating vegetation index time series and meteorological data to understand the effect of the land use/land cover (LULC) in the climatic seasonality of the Brazilian Cerrado  

Science.gov (United States)

The Cerrado (savanna ecosystem) of São Paulo state (Brazil) represent a complex mosaic of different typologies of uses, actors and biophysical and social restrictions. Originally, 14% of the state of São Paulo area was covered by the diversity of Cerrado phytophysiognomies. Currently, only 1% of this original composition remains fragmented into numerous relicts of biodiversity, mainly concentrated in the central-eastern of the state. A relevant part of the fragments are found in areas of intense coverage change by human activities, whereas the greatest pressure comes from sugar cane cultivation, either by direct replacement of Cerrado vegetation or occupying pasture areas in the fragments edges. As a result, new local level dynamics has been introduced, directly or indirectly, affecting the established of processes in climate systems. In this study, the main goal is analyzing the relationship between the Cerrado landscape changing and the climate dynamics in regional and local areas. The multi-temporal MODIS 250 m Vegetation Index (VI) datasets (period of 2000 to 2012) are integrated with precipitation data of the correspondent period (http://www.agritempo.gov.br/),one of the most important variable of the spatial phytophysiognomies distribution. The integration of meteorological data enable the development of an integrated approach to understand the relationship between climatic seasonality and the changes in the spatial patterns. A procedure to congregated diverse dynamics information is the Self Organizing Map (SOM, Kohonen, 2001), a technique that relies on unsupervised competitive learning (Kohonen and Somervuo 2002) to recognize patterns. In this approach, high-dimensional data are represented on two dimensions, making possible to obtain patterns that takes into account information from different natures. Observed advances will contribute to bring machine-learning techniques as a valid tool to provide improve in land use/land cover (LULC) analyzes at different hierarchical scales to support numerous science and policy applications.

Lins, D. B.; Zullo, J.; Friedel, M. J.

2013-12-01

159

Morphological changes and vegetation index variation along the western coastal zone of Bangladesh  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Being a low laying deltaic country, morphological changes along the Bangladesh coastal zones are of major socio-economic and environmental concern. In this study, images of LANDSAT captured during 1989-2010 are analyzed to detect the variation of shoreline positions. Western coast has been divided into different segments and the rates of change of shoreline positions have been analyzed over three time periods 1989-2000, 2000-2006 and 2006-2010. AVHRR GIMMS and MODIS NDVI (Normalized Differenc...

Shibly, A. Md; Takekawa, S.

2013-01-01

160

Influência de retardante vegetal e densidades de plantas sobre o crescimento, acamamento e produtividade da soja = Influence of vegetal retardant and densities of sowing on the growth, fallen plant index and yield of soybean  

Directory of Open Access Journals (Sweden)

Full Text Available A soja é o principal produto agrícola mundial, justificando investimentos em tecnologias que visem ao aumento da produção e à redução dos fatores adversos à cultura. Desta forma, este trabalho tem como objetivo avaliar o efeito de retardante vegetal, emdiferentes densidades de semeadura sobre o crescimento, componentes de produção, produtividade e acamamento na cultura da soja. O experimento foi desenvolvido no Centro Tecnológico Coopavel - Cascavel, Estado do Paraná. O delineamento experimentalconstitui-se de blocos inteiramente casualizados, com quatro repetições, em esquema fatorial (6x2, sendo os tratamentos obtidos pela combinação das seis doses do retardante e duas densidades de semeadura. Realizaram-se avaliações a cada 14 dias, a partir de 21 dias após a emergência (DAE até o florescimento da cultura, obtendo-se diâmetro de caule e altura de planta, também se realizaram três coletas (35, 70 e 100 DAE para obter massa seca nos diferentes órgãos da planta e área foliar. Na colheita, avaliaram-se os componentes da produção e acamamento. O retardante vegetal e a densidade de plantas influenciaram na altura e diâmetro de caule das plantas, entretanto, para massa seca, área foliar, componentesda produção, produtividade e acamamento, não houve influência do retardante; contudo, a densidade de semeadura afetou a massa seca.Soybean is the main agricultural product worldwide, meriting investments in technology with aims of increasing production as wellas reducing adverse crop factors. Thus, this work had as objective to evaluate the effect of growth retardant - in different sowing densities - on growth, production components, yield and lodging in soybean crops. The experiment was developed at the CoopavelTechnological Center, Cascavel – Parana State, Brazil. The experimental design was arranged in completely randomized blocks with four replications, in a factorial experiment (6x2, with treatments obtained through the combination of six levels of retardant and twosowing densities. Evaluations were undertaken every 14 days, starting 21 days after emergence (DAE until bloom. At this time, stem diameter and plant height were measured. Three collections were made (35, 70 and 100 DAE, in order to calculate dry mass in the different plant parts and leaf area. At harvest, the production components andlodging index were evaluated. The growth retardant and plant density influenced the height and stem diameter of the plants. However, the retardant did not affect dry mass, leaf area, production components, yield and lodging index, but density did affect dry mass.

Rodolfo Linzmeyer Junior

2008-07-01

 
 
 
 
161

Influência de retardante vegetal e densidades de plantas sobre o crescimento, acamamento e produtividade da soja / Influence of vegetal retardant and densities of sowing on the growth, fallen plant index and yield of soybean  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese A soja é o principal produto agrícola mundial, justificando investimentos em tecnologias que visem ao aumento da produção e à redução dos fatores adversos à cultura. Desta forma, este trabalho tem como objetivo avaliar o efeito de retardante vegetal, em diferentes densidades de semeadura sobre o cre [...] scimento, componentes de produção, produtividade e acamamento na cultura da soja. O experimento foi desenvolvido no Centro Tecnológico Coopavel - Cascavel, Estado do Paraná. O delineamento experimental constitui-se de blocos inteiramente casualizados, com quatro repetições, em esquema fatorial (6x2), sendo os tratamentos obtidos pela combinação das seis doses do retardante e duas densidades de semeadura. Realizaram-se avaliações a cada 14 dias, a partir de 21 dias após a emergência (DAE) até o florescimento da cultura, obtendo-se diâmetro de caule e altura de planta, também se realizaram três coletas (35, 70 e 100 DAE) para obter massa seca nos diferentes órgãos da planta e área foliar. Na colheita, avaliaram-se os componentes da produção e acamamento. O retardante vegetal e a densidade de plantas influenciaram na altura e diâmetro de caule das plantas, entretanto, para massa seca, área foliar, componentes da produção, produtividade e acamamento, não houve influência do retardante; contudo, a densidade de semeadura afetou a massa seca. Abstract in english Soybean is the main agricultural product worldwide, meriting investments in technology with aims of increasing production as well as reducing adverse crop factors. Thus, this work had as objective to evaluate the effect of growth retardant - in different sowing densities - on growth, production comp [...] onents, yield and lodging in soybean crops. The experiment was developed at the Coopavel Technological Center, Cascavel - Parana State, Brazil. The experimental design was arranged in completely randomized blocks with four replications, in a factorial experiment (6x2), with treatments obtained through the combination of six levels of retardant and two sowing densities. Evaluations were undertaken every 14 days, starting 21 days after emergence (DAE) until bloom. At this time, stem diameter and plant height were measured. Three collections were made (35, 70 and 100 DAE), in order to calculate dry mass in the different plant parts and leaf area. At harvest, the production components and lodging index were evaluated. The growth retardant and plant density influenced the height and stem diameter of the plants. However, the retardant did not affect dry mass, leaf area, production components, yield and lodging index, but density did affect dry mass.

Rodolfo, Linzmeyer Junior; Vandeir Francisco, Guimarães; Diego dos, Santos; Michel Henrique, Bencke.

162

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)

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.

Jonathan Quaye

2010-01-01

163

Individual differences in fornix microstructure and body mass index.  

Science.gov (United States)

The prevalence of obesity and associated health conditions is increasing in the developed world. Obesity is related to atrophy and dysfunction of the hippocampus and hippocampal lesions may lead to increased appetite and weight gain. The hippocampus is connected via the fornix tract to the hypothalamus, orbitofrontal cortex, and the nucleus accumbens, all key structures for homeostatic and reward related control of food intake. The present study employed diffusion MRI tractography to investigate the relationship between microstructural properties of the fornix and variation in Body Mass Index (BMI), within normal and overweight ranges, in a group of community-dwelling older adults (53-93 years old). Larger BMI was associated with larger axial and mean diffusivity in the fornix (r = 0.64 and r = 0.55 respectively), relationships that were most pronounced in overweight individuals. Moreover, controlling for age, education, cognitive performance, blood pressure and global brain volume increased these correlations. Similar associations were not found in the parahippocampal cingulum, a comparison temporal association pathway. Thus, microstructural changes in fornix white matter were observed in older adults with increasing BMI levels from within normal to overweight ranges, so are not exclusively related to obesity. We propose that hippocampal-hypothalamic-prefrontal interactions, mediated by the fornix, contribute to the healthy functioning of networks involved in food intake control. The fornix, in turn, may display alterations in microstructure that reflect weight gain. PMID:23555805

Metzler-Baddeley, Claudia; Baddeley, Roland J; Jones, Derek K; Aggleton, John P; O'Sullivan, Michael J

2013-01-01

164

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)

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).

Schmidt, M.; Udelhoven, T.

2012-07-01

165

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

Science.gov (United States)

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.

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

166

Intra-annual Dynamical Persistent Mechanisms in Mediterranean Ecosystems Revealed SPOT-VEGETATION Time Series Ecosystems Revealed SPOT-VEGETATION Time Series  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Multitemporal series of satellite SPOT-VEGETATION Normalized Difference of Vegetation Index (NDVI) and Normalized Difference Infrared Index (NDII) data from 1998 to 2003 were exploited for studying persistence in Mediterranean ecosystems of the Sardinia Region (southern Italy). Three different vegetation covers (shrub-land, transitional and forest) were analysed. The NDVI and NDII provide information on the vegetation status and water content respectively. The Detrended Fluctuation Analysis ...

Telesca, L.; Lasaponara, R.; Lanorte, A.

2008-01-01

167

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

168

Analysis of Vegetation Behavior in a North African Semi-Arid Region, Using SPOT-VEGETATION NDVI Data  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The analysis of vegetation dynamics is essential in semi-arid regions, in particular because of the frequent occurrence of long periods of drought. In this paper, multi-temporal series of the Normalized Difference of Vegetation Index (NDVI), derived from SPOT-VEGETATION satellite data between September 1998 and June 2010, were used to analyze the vegetation dynamics over the semi-arid central region of Tunisia. A study of the persistence of three types of vegetation (pastures, annual agricult...

Rim Amri; Mehrez Zribi; Zohra Lili-Chabaane; Benoit Duchemin; Claire Gruhier; Abdelghani Chehbouni

2011-01-01

169

Sacrum Index in Children Suffering from Different Grades of Vesicoureteral Reflux  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study aimed at evaluating the sacrum index in children suffering from different grades of vesicoureteral reflux. In this case-control study, according to VCUG results, children with grade III, IV and V refluxes entered the study. There were 76 children with history of urinary canal infection and normal VCUG. Sacrum index was measured in both groups and compared. There was a meaningful relationship between these two groups considering abnormality rate of the index (p = 0.001). The factor ...

Parsa Yousefi; Ali Siroos; Fatemeh Darreh; Masoumeh Ahmadi Mohtasham; Farnaz Hafez Qoran; Mohamad Goldust

2013-01-01

170

Description of psychophysiological indexes of students of different sporting specializations  

Directory of Open Access Journals (Sweden)

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.

Barybina L.N.

2010-08-01

171

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

Directory of Open Access Journals (Sweden)

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.

Ertan Yildirim

2002-12-01

172

Index  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 o...

Antonio Juan Sánchez

2013-01-01

173

Application of an innovative technique for histological and histochemical study of different vegetal tissues  

Digital Repository Infrastructure Vision for European Research (DRIVER)

A new original "cryostabilization" technique was applied to different animal tissues and organs. In this study, we apply this technique also to vegetal tissues (ripening and ripe fleshy fruits, buds and embryos). The proposed method preserves good tissue morphology and intracellular substances, and avoids loss of epicuticular waxes; moreover it maintains in situ some enzymatic activities. Being some samples very difficult to handle the original protocol had to be modified process. The correct...

Dore, Bruno Emilio

2009-01-01

174

Fatty acid composition of lambs suckling ewes fed with different vegetable oils  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Forty eight Churra ewes were used to study the effects of supplementing diets with 3% of different vegetable oils (linseed oil, L; soya oil, S; olive oil, O) or hydrogenated palm oil (Control, C) on fatty acid composition of suckling lambs covered by the protected geographical indication (PGI) “Lechazo de Castilla y León”. The lambs were suckled by their dams and slaughtered when they reached 11 kg body weight. Samples from intramuscular and subcutaneous fat were taken. Regardless the de...

2009-01-01

175

The vegetative development of Sinningia leucotricha Hoehne (Moore) under different levels of shading  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This work aimed at the assessment of the influence of different levels of shading in the development of (Sinningia leucotricha Hoehne (Moore). Tuberous roots of 2.3 ± 0.3 cm in diameter were used as vegetative material. The cultivation was performed in plastic vases and gross sand as substrate, and conditioned in sheltered nurseries protected by black polypropylene nets in the followings percentages: 0% (under full sunlight), 50, 60, and 70%. Sheltered nurseries with 60 or 70% of shading pre...

Lilian Keiko Unemoto; Ricardo Tadeu de Faria; Adriane Marinho Assis; Deonisio Destro

2010-01-01

176

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 o...

Drago?-Sorin Fota; Lavinia ?tef; Dan Drinceanu; Izabella Fota; Rodica C?pri??; Eliza Simiz

2011-01-01

177

Effect of Different Cooking Methods on the Content of Vitamin C in Some Vegetables  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Background and objective: Vitamin C is considered as the indicator of process severity, because of its high sensitivity to heat. There is an inverse relationship between vitamin C retention and the process severity. The aim of this study was to determine the effect of different common cooking methods on process severity and decrease amount of vitamin C in some vegetables.Materials and methods: In this study, potatoes were tested as boiled (with peel, without peel, sliced), shallow and deep fr...

2011-01-01

178

Diversity of Halophyte Desert Vegetation of the Different Saline Habitats in the Valley of Oued Righ, Low Sahara Basin, Algeria  

Directory of Open Access Journals (Sweden)

Full Text Available The aim of the present study was to investigate the floristic composition and diversity of the different habitat types in the saline areas of the valley of Oued Righ, locating in the low Sahara basin of Algeria. Three distinct saline habitats were examined: saline soil habitats, subsaline soil habitats, and waterlogged habitats. A total of 67 stands along the study area were investigated using the quadrat method, and different vegetation parameters, such as cover, frequency, density, and Importance Value Index (IVI, were recorded. Differences of species diversity and richness between saline habitats were also compared. A total of 38 plant species belonging to 29 genera and 13 families were identified from the three studied habitats. Chenopodiaceae was the predominant family. The majority of the species were of Saharo-Arabian distribution. Chemaephytes had the highest contribution to the life forms spectra. Species composition in the different habitat types showed differences in species richness. Subsaline soil habitats were the most diverse, followed by saline soil habitats. Waterlogged habitats had the lowest diversity. The floristic composition and the dominant species of each habitat were presented. The potential role of the halophyte species was discussed. These findings may lead to a better understanding of the functions, requirements, and sensitivities of these ecosystems.

Belhamra Mohamed

2012-03-01

179

Comparative study of trace element levels in some local vegetable varieties and irrigation waters from different locations in Ilorin, Nigeria  

Directory of Open Access Journals (Sweden)

Full Text Available The level of heavy metals in two varieties of vegetables harvested during the dry and wet seasons from seven different locations in Ilorin, Nigeria, were determined. The correlation between the level of metals in the vegetables and the irrigation water was also studied. Vegetables harvested during the dry season were found to contain higher level of toxic metals. Low water quality, accumulation of particulate after rainless period and nearness of some vegetable gardens to major and well travelled roads appeared to be the major contributory factors. Amaranthus hybridus seemed to have higher metal accumulation capacity compared to Corchorus olitorius mannii.

O.O. Dosumu

2003-06-01

180

Water regime of soils under the different vegetative cover, the Giant Mountains, Czech Republic.  

Science.gov (United States)

Several monitored plots, located in the Giant Mountains in different positions (valley, slope), are covered by different vegetation (dwarf pine forest, spruce forest, meadow). Soil moisture properties in relation to vegetative cover (dwarf pine versus grassland stands) were studied from the year 2000 to 2006. The main goal was to analyse chosen rainfall-runoff periods with respect to diferent vegetative cover. Every plot was arranged by automatic station for continual soil moisture measurements by VIRRIB sensors (Phase Transmition) in depth of 15 and 45 cm, tensiometer suction presure in depth of 15, 30, 45 and 60 cm and temperature of soil and air. Three plots were also arranged by rain gauges for precipitation measurements in the vegetation season. To complete the characteristics of the unsaturated zone the particle-size analysis and retention curves for depths of 15, 30, 45 and 60 cm were done. Four groups of three rod probes (0.3, 0.6 and 0.9 m) for TDR (Time Domain Reflectometry) soil moisture measurements for seven plots were installed. The irregular measurements were done during 2000, 2001, 2002 and 2003 vegetation seasons. The values of soil moisture for depth intervals of 0-30 cm, 30-60 cm and 60-90 cm were computed for each plot. The TDR values of soil moisture are generally lower than the results obtained from VIRRIB sensors. The explanation of this fact should be that the used TDR measurements involve bigger interval of soil profile than VIRRIB sensors which measure smaller area of soil. The other reason could be the diferent way of probe instalation for each method. The results were compared with the data obtained from VIRRIB sensors, and where possible, the TDR data was used for giving precision to the VIRRIB data. Significant influence of diferent vegetative cover on water regime in soils of tundra area of the Giant Mountains was determined but not sufficiently explained yet. Surprisingly the water regime under the grassland showed similar behavior as a forest area against the dwarf pine stands during the most rainfall-runoff periods studied. The research is supported by the Czech Science Foundation (Projects No. 205/08/1174 and 526/08/1016).

Dvorak, I. J.; Tesar, M.; M., Sir; Dohnal, J.

2009-04-01

 
 
 
 
181

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)

2001-01-01

182

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

Miura, Tomoaki; Yoshioka, Hiroki; Fujiwara, Kayo; Yamamoto, Hirokazu

2008-01-01

183

Diseño de un índice espectral de la vegetación desde una perspectiva conjunta de los patrones exponenciales y lineales del crecimiento / Design of a spectral vegetation index under the joint perspective of exponential and linear growth patterns  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: Spanish Abstract in spanish En este trabajo se analizan diferentes experimentos con mediciones de reflectancia para revisar los patrones de las primeras dos constantes de los modelos de interacciones radiativas en el espacio del rojo (R) e infrarrojo cercano (IRC), concluyéndose de la evidencia experimental que el modelo de in [...] teracciones de orden uno es suficiente para este fin. En segundo lugar se desarrolla el algoritmo del índice espectral IV_CIMAS y se aplica a experimentos de cultivos, concluyéndose que este índice sólo tiene una relativa mejoría en relación con el índice NDVIcp, y que ambos describen bien la fase expo-lineal de la etapa vegetativa de la vegetación. La fase reproductiva no es modelada en forma adecuada por ninguno de los índices espectrales. Finalmente, se revisan los modelos de la geometría sol-sensor propuestos, y se concluye que éstos tienen buenos ajustes experimentales, permitiendo estandarizar esta geometría. La modelación de los patrones asociados a las constantes de las curvas espectrales de igual vegetación es muy difícil de realizar por las propiedades de los espacios usados. El problema del diseño de índices de vegetación es todavía un problema abierto. Abstract in english This study analyzes different experiments with reflectance measurements to review the patterns of the first two constants of the models of radiative interaction in the red (R) and near infrared (NIR) space. From experimental evidence, it is concluded that the first order model of interactions is suf [...] ficient for this aim. Secondly, the algorithm of the spectral index IV_CIMAS is developed and applied to crop experiments, concluding that this index is only a relative improvement over the NDVIcp index and that the expo-linear phase of the vegetative growth stage of the vegetation are well-described by both. The reproductive phase is not adequately modeled by either of the spectral indexes. Finally, the models of sun-sensor geometry proposed are reviewed, and it is concluded that these have good experimental fit, allowing this geometry to be standardized. Modeling of the associated patterns to the spectral curve constants of equal vegetation is very difficult to do because of properties of the spaces used. The problem of designing vegetation indexes is still open.

Romero-Sánchez, Enrique; Paz-Pellat, Fernando; Palacios-Vélez, Enrique; Bolaños-González, Martín; Valdez-Lazalde, René; Aldrete, Arnulfo.

184

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 - inclus...

Abg, Faitarone; Ea, Garcia; Roc?a, R. O.; Ricardo, H. A.; Andrade, E. N.; Peli?cia, K.; Vercese, F.

2013-01-01

185

IDENTIFYING RECENT SURFACE MINING ACTIVITIES USING A NORMALIZED DIFFERENCE VEGETATION INDEX (NDVI) CHANGE DETECTION METHOD  

Science.gov (United States)

Coal mining is a major resource extraction activity on the Appalachian Mountains. The increased size and frequency of a specific type of surface mining, known as mountain top removal-valley fill, has in recent years raised various environmental concerns. During mountainto...

186

An Empirical Algorithm for Estimating Agricultural and Riparian Evapotranspiration Using MODIS Enhanced Vegetation Index and Ground Measurements of ET. II. Application to the Lower Colorado River, U.S.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Large quantities of water are consumed by irrigated crops and riparian vegetation in western U.S. irrigation districts. Remote sensing methods for estimating evaporative water losses by soil and vegetation (evapotranspiration, ET) over wide river stretches are needed to allocate water for agricultural and environmental needs. We used the Enhanced Vegetation Index (EVI) from MODIS sensors on the Terra satellite to scale ET over agricultural and riparian areas along the Lower Colorado River in ...

Scott Murray, R.; Nagler, Pamela L.; Kiyomi Morino; Glenn, Edward P.

2009-01-01

187

Vegetation differences and diagenetic changes between two Bulgarian lignite deposits - Insights from coal petrology and biomarker composition  

Energy Technology Data Exchange (ETDEWEB)

In this study, we review the petrographic composition and biomarker assemblage of two adjacent basins in western Bulgaria, i.e. Beli Breg and Staniantsi basins. Both contain lignite formed during late Miocene (c. 6 Ma). Despite similar tectonic settings and depositional environments, the lignite seams possess different petrographic and organic geochemical characteristics, reflecting differences in the peat forming palaeo-communities and fades variations. The peat-forming vegetation in Bell Breg Basin was dominated by decay resistant coniferous plants, as indicated by abundant fossil wood remains, very good tissue preservation and a biomarker assemblage dominated by diterpenoids. In contrast, Staniantsi lignite is poor in fossil wood and contains a significant amount of triterpenoid biomarkers, suggesting the predominance of angiosperm plants in the swamp. The results of the biomarker analyses are consistent with palaeobotanical and palynological data from the literature. The lignite seams in both basins formed under frequently changing Eh conditions, as indicated by the severe degradation of the non-gymnosperm tissues, the low gelification index values and the variations in pristane/phytane ratio, probably as a result of seasonal drying of the swamps and changes of the ground water table. Hopanoid contents in Bell Breg lignite are very low and are consistent with the abundance of decay-resistant vegetation. In contrast, bacterial activity was obviously higher in the Staniantsi swamp, however, resulting only in slightly enhanced gelification of plant tissues. The geochemical data suggest that the diagenetic changes of the organic matter were mainly governed by thermal degradation, rather than bacterial activity.

Zdravkov, A.; Bechtel, A.; Sachsenhofer, R.F.; Kortenski, J.; Gratzer, R. [University of Mining & Geology St Ivan Rilski, Sofia (Bulgaria)

2011-03-15

188

[Effects of different vegetation restoration of degraded red soil on earthworm population dynamics].  

Science.gov (United States)

This study was conducted at the long-term experimental plots in Ecological Experimental Station of Red Soil in Yujiang County (28 degrees 15'30''N, 116 degrees 55'30''E ), Jiangxi Province, subtropical China. Earthworm population was investigated seasonally from May 1999 to February 2000, under different vegetations including four artificial woodlands [deciduous broadleaf woodland (Quercus chenii, Qc), evergreen broadleaf woodland (Schima superba, Ss), coniferous woodland (Pinus massonina, Pm) and mixed woodland (Schima superba-Pinus massonina, Sm)], two grasslands [gently-disturbed grassland (G1), undisturbed grassland (G2)] and control wasteland (CK). The results indicated that the population structure was very simple. Only Drawinda gisti characterized by pioneer was found. The seasonal averages of density and biomass were in the order of G2 > G1 > Qc > Ss > Pm > Sm > CK, and those of G2, G1 and Qc were significantly higher than those of the latters (P stability, followed by Sm and Ss, and G1, G2, and Pm had the lowest stability. The overall differentiation of earthworm population could be drawn through canonical discriminant analysis. There were significant correlations between earthworms and some soil properties (P < 0.01). Overall, the differentiation of earthworm population was driven by the quantity and quality of soil organic matter returned by the vegetations. Additionally, based on earthworm population, the importance of selecting appropriate vegetation types during the restoration of degraded red soil was emphasized. PMID:15707332

Liu, Manqiang; Hu, Feng; Chen, Xiaoyun; He, Yuanqiu; Li, Huixin

2004-11-01

189

A Single Amino Acid Difference Is Sufficient to Elicit Vegetative Incompatibility in the Fungus Podospora Anserina  

Science.gov (United States)

Vegetative incompatibility is known to limit heterokaryosis in filamentous fungi. It results from genetic differences between incompatible strains at specific loci. The proteins encoded by the two incompatible alleles het-s and het-S of the fungus Podospora anserina differ from each other by 14 amino acids. Two approaches have been used to identify how many and which of these differences are necessary to elicit incompatibility. Twelve alleles of the het-s locus of wild-type isolates of P. anserina and of the related species Podospora comata have been sequenced to determine the extent of the variability of genes controlling s and S specificities. Expression of hybrid het-s/het-S genes and site-specific mutagenesis revealed that the specificities of het-s and het-S are under the control of a limited number of amino acid differences. The results show that vegetative incompatibility between s and S strains can be attributed to a single amino acid difference in the proteins encoded by the het-s locus.

Deleu, C.; Clave, C.; Begueret, J.

1993-01-01

190

Resting-state EEG study of comatose patients: a connectivity and frequency analysis to find differences between vegetative and minimally conscious states.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The aim of this study was to look for differences in the power spectra and in EEG connectivity measures between patients in the vegetative state (VS/UWS) and patients in the minimally conscious state (MCS). The EEG of 31 patients was recorded and analyzed. Power spectra were obtained using modern multitaper methods. Three connectivity measures (coherence, the imaginary part of coherency and the phase lag index) were computed. Of the 31 patients, 21 were diagnosed as MCS and 10 as VS/UWS using...

Lehembre, Remy; Bruno, Marie-aure?lie; Vanhaudenhuyse, Audrey; Chatelle, Camille; Cologan, Victor; Leclercq, Yves; Soddu, Andrea; Macq, Benoit; Laureys, Steven; Noirhomme, Quentin

2012-01-01

191

Sacrum index in children suffering from different grades of vesicoureteral reflux.  

Science.gov (United States)

This study aimed at evaluating the sacrum index in children suffering from different grades of vesicoureteral reflux. In this case-control study, according to VCUG results, children with grade III, IV and V refluxes entered the study. There were 76 children with history of urinary canal infection and normal VCUG. Sacrum index was measured in both groups and compared. There was a meaningful relationship between these two groups considering abnormality rate of the index (p = 0.001). The factor can be used as a predictive factor in determining prognosis of medical treatment and selecting those children candidate to surgery. PMID:24498825

Yousefi, Parsa; Siroos, Ali; Darreh, Fatemeh; Mohtasham, Masoumeh Ahmadi; Qoran, Farnaz Hafez; Goldust, Mohamad

2013-06-01

192

Sacrum Index in Children Suffering from Different Grades of Vesicoureteral Reflux  

Directory of Open Access Journals (Sweden)

Full Text Available This study aimed at evaluating the sacrum index in children suffering from different grades of vesicoureteral reflux. In this case-control study, according to VCUG results, children with grade III, IV and V refluxes entered the study. There were 76 children with history of urinary canal infection and normal VCUG. Sacrum index was measured in both groups and compared. There was a meaningful relationship between these two groups considering abnormality rate of the index (p = 0.001. The factor can be used as a predictive factor in determining prognosis of medical treatment and selecting those children candidate to surgery.

Farnaz Hafez Qoran

2013-01-01

193

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

Science.gov (United States)

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

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

2014-01-31

194

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

Science.gov (United States)

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.

Yin, Z.; Dekker, S. C.; van den Hurk, B. J. J. M.; Dijkstra, H. A.

2014-05-01

195

Derivation of Relationships between Spectral Vegetation Indices from Multiple Sensors Based on Vegetation Isolines  

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An analytical form of relationship between spectral vegetation indices (VI) is derived in the context of cross calibration and translation of vegetation index products from different sensors. The derivation has been carried out based on vegetation isoline equations that relate two reflectance values observed at different wavelength ranges often represented by spectral band passes. The derivation was first introduced and explained conceptually by assuming a general functional form for VI model...

Hiroki Yoshioka; Tomoaki Miura; Kenta Obata

2012-01-01

196

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

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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.

Algimantas Me?islovas Olšausaks

2009-12-01

197

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

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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

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

2011-12-01

198

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

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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…

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

2013-01-01

199

Multifractal analysis of SSEC in Chinese stock market: A different empirical result from Heng Seng index  

Science.gov (United States)

In this paper, high frequency (per 5 min) data of Shanghai Stock Exchange Composite index (SSEC) from January 1999 to July 2001 is analyzed by multifractal. We find that the correlation of the parameters of the multifractal spectra with the variation of daily return Z in SSEC is noticeably different from that in previous studies of Heng Seng index in Hong Kong stock market [Sun et al., Phys. A 291 (2001) 553-562; Sun et al., Phys. A 301 (2001) 473-482]. So, we suppose that there may not be a universal rule for the dependence of the parameters of the multifractal spectra with daily return of a stock index. Then, we construct a new measurement of market risk based on multifractal spectra, and test its ability of predicting index fluctuations with a more thorough method than that in Sun et al. [Phys. A 301 (2001) 473-482].

Wei, Yu; Huang, Dengshi

2005-09-01

200

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

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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.

Edward P. Glenn

2009-12-01

 
 
 
 
201

Exploiting the MODIS albedos with the Two-stream Inversion Package (JRC-TIP): 1. Effective leaf area index, vegetation, and soil properties  

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This contribution illustrates results from a large-scale application of the Joint Research Centre Two-stream Inversion Package (JRC-TIP), using MODIS broadband visible and near-infrared white sky surface albedos as inputs. The discussion focuses on products (based on the mean and one-sigma values of the probability distribution functions (PDFs)) obtained during the summer and winter. This paper discusses the retrieved model parameters including the effective leaf area index (LAI), the background brightness, and the scattering efficiency of the vegetation elements. The similarity between the derived LAI seasonal maps and earlier distributions of this variable comforts us in the quality of the albedo products as well as in the ability of the JRC-TIP to interpret the latter meaningfully. The opportunity to generate global maps of new products, such as the background albedo, underscores the advantages of using state of the art algorithmic approaches capable of fully exploiting accurate satellite remote sensing data sets. The detailed analyses of the retrieval uncertainties highlight the central role and contribution of the LAI, the main process parameter to interpret radiation transfer observations over vegetated surfaces. The estimation of the radiation fluxes that are absorbed, transmitted, and scattered by the vegetation layer and its background is achieved on the basis of the retrieved PDFs of the model parameters. Results from this latter step are discussed in a companion paper.

Pinty, B.; Andredakis, I.; Clerici, M.; Kaminski, T.; Taberner, M.; Verstraete, M. M.; Gobron, N.; Plummer, S.; Widlowski, J.-L.

2011-05-01

202

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

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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 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 GPP in remote Arctic regions.

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

2013-12-01

203

Characteristics of Photosynthetic Behaviors and Chlorophyll Fluorescence in Different Vegetable Species  

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Full Text Available This study investigated the variability in the various physiological characteristics of seven popular commercial vegetable seedlings such as cabbage, spinach, Chinese cabbage, eggplant cucumber, tomato and Chinese radish. The photosynthetic rate (Pn was higher in cabbage seedlings followed by eggplant seedlings. Chinese cabbage and cabbage seedlings showed higher stomatal conductance (CS than other vegetables studied. Cucumber seedlings had higher respiration rate followed by tomato, egg plant and Chinese radish. In the case of internal CO2 concentration, all the species studied differ significantly. Chinese cabbage seedlings exhibited the highest transpiration rate (Tr and Chinese radish had the lowest. There was little decrease in photochemical efficiency of PS II i.e., Fv/Fm value of chlorophyll fluorescence in all species, however cabbage and spinach seedling had the highest Fv/Fm value followed by cucumber, tomato and eggplant seedlings. Among all the physiological parameters, Pn was highly correlated with Fv/Fm value. The results may be useful in formulating efficient selection and breeding programs in improving desired quality characteristics of plant species.

Sharmin Khan

2006-01-01

204

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

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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.

Drago?-Sorin Fota

2011-05-01

205

The vegetative development of Sinningia leucotricha Hoehne (Moore under different levels of shading  

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Full Text Available This work aimed at the assessment of the influence of different levels of shading in the development of (Sinningia leucotricha Hoehne (Moore. Tuberous roots of 2.3 ± 0.3 cm in diameter were used as vegetative material. The cultivation was performed in plastic vases and gross sand as substrate, and conditioned in sheltered nurseries protected by black polypropylene nets in the followings percentages: 0% (under full sunlight, 50, 60, and 70%. Sheltered nurseries with 60 or 70% of shading presented the highest vegetative development for Brazilian edelweiss. The cultivation of this species under full sunlight is not recommended.A rainha-do-abismo (Sinningia leucotricha Hoehne (Moore é uma planta nativa do Estado do Paraná, se destaca pela beleza de suas folhas de aspecto prateado. Este trabalho teve como objetivo avaliar a influência de diferentes níveis de sombreamento no desenvolvimento de plantas de rainha-do-abismo. Para o experimento foram utilizadas como material vegetativo raízes tuberosas com 2,3 ± 0,3 cm de diâmetro. O cultivo foi realizado em vasos plásticos e areia grossa como substrato, que foram acondicionados em viveiros protegidos com tela de polipropileno de coloração preta, nas seguintes porcentagens: 0% (a pleno sol 50%, 60% e 70%. Viveiros protegidos com 60% ou 70% de sombreamento foram os que proporcionaram maior desenvolvimento vegetativo de rainha-do-abismo. O cultivo desta espécie a pleno sol não é recomendado.

Lilian Keiko Unemoto

2010-02-01

206

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

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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 compon...

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

2013-01-01

207

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

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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...

2009-01-01

208

Diagnostic Utility of WISC-IV General Abilities Index and Cognitive Proficiency Index Difference Scores among Children with ADHD  

Science.gov (United States)

The Wechsler Intelligence Scale for Children-Fourth Edition General Abilities Index and Cognitive Proficiency Index have been advanced as possible diagnostic markers of attention deficit hyperactivity disorder. This hypothesis was tested with a hospital sample with attention deficit hyperactivity disorder (n = 78), a referred but nondiagnosed…

Devena, Sarah E.; Watkins, Marley W.

2012-01-01

209

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

2013-09-01

210

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

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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

Juan José Neiff

2009-03-01

211

Checking various vegetation indices for estimating vegetation in arid regions and Presented a model (Case Study:Sadough- Yazd)  

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Vegetation is one of the natural recourses components and achieve Quantitative information of them have a major role in the management of land. Using satellite images is one of the new techniques in the field of qualitative and quantitative studies of the vegetation .Studies show that the use of spectral vegetation indices and ratios may serve as a useful approach in this area, especially in the desert zoon. In this study, using Landsat TM imagery sensors, to calculate different vegetation indices and their ability checking vegetation in arid regions. After multivariate regression analysis between the actual values and parameters, and validation of models optimal model was selected. The results showed that the index of ARVI with the corresponding coefficients is better results in estimating the amount of vegetation in arid regions. Keywords: vegetation, satellite images, vegetation index, arid region, Saduq

Kalantari, Saeideh; Zehtabian, Gholamreza; Azarnivand, Hossein; Ahmadi, Hassan

2013-04-01

212

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

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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

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

2014-05-01

213

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

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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.

ABG Faitarone

2013-03-01

214

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

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

215

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

Science.gov (United States)

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

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

2013-12-01

216

Variations in chemical composition of grass clover mixtures over the vegetation season in different agroecological conditions  

Directory of Open Access Journals (Sweden)

Full Text Available The aim of the current investigation carried out on 6 family farms in 6 counties was to determine seasonal variations in chemical composition of domestic and Canadian grass-clover mixture (GCM. The study was arranged as complete randomly design on 1 ha area at each of the family farm involved (0.5 ha domestic, 0.5 ha Canadian GCM. The sward at each family farm was cut five times over the vegetation season. GCM samples were analyzed by NIR spectroscopy (NIR instrument, Foss, Model 6500 to determine: dry matter (DM, organic matter (OM, crude protein (CP, neutral detergent fiber (NDF, metabolic energy (ME, digestibility of OM in DM (D-value and water-soluble carbohydrates (WSC. No differences in chemical composition between the two GCM were observed, but among locations for DM, OM and WSC. The interaction of mixture x location was significant (P0.05. This means that no significant differences were noticed between mixtures at the same term of cutting, but for all of the investigated parameters among cuttings. There quality of GCM was increasing over the season as seen from its relative increase in CP from the first (112.9 g kg-1 to the fifth cut (185.9 g kg-1. NDF was higher over the whole vegetation season. The last cut showed significantly lower NDF (628.6 g kg-1, higher ME (10,73 MJ kg-1, D-value (71.6 and WSC (56.3 g kg-1.

Goran Per?ulija

2005-10-01

217

Production characteristics of Papaver somniferum L. cultivars of different origin and vegetation cycles.  

Science.gov (United States)

Poppy cultivars of different origin were investigated in long-term experiments during the period 1976-1980. The production ability of plants was established with both spring and autumn sowing, using different plant spacing (20 cm X 20 cm and 50 cm X 20 cm). All important poppy-growing areas within northern and southern Europe were represented by the cultivars brought under investigation ("P-360", "Ankara", "Botosani", "Kompolti-M", "Kék Duna", "Modran", "KM-Ihar" and "Reading"). The extension of the vegetation cycle by autumn sowing and wintering had a generally favourable effect on dry matter and alkaloid production, resulting in a fivefold increase in production. In spite of high production ability, the wintering of the cold-sensitive cultivars, known as spring types, was uncertain. The shortening of the vegetation cycle (spring sowing) seemed to be unfavourable for the production of both spring and autumn cultivars. However, that disadvantage was compensated to some extent by spring cultivars having relatively lower sensitivity and higher alkaloid production levels. The weight of individual plants was much higher when cultivated in large areas. However, a higher yield could be obtained with 20cm X 20cm spacing because more plants could be harvested per square metre. On the basis of production analyses, a negative correlation was established between the total capsule mass (i.e. capsule plus seed) and the ratio of the drug-forming part. In the case of alkaloid production, a positive correlation was established between the accumulation of codeine and the intensification of over-all alkaloid formation. PMID:6926513

Bernáth, J; Tétényi, P

1982-01-01

218

Differences in fruit and vegetable intake and their determinants among 11-year-old schoolchildren between 2003 and 2009  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Fruit and vegetable (FV intake in children in the Netherlands is much lower than recommended. Recurrent appraisal of intake levels is important for detecting changes in intake over time and to inform future interventions and policies. The aim of the present study was to investigate differences in fruit and vegetable intake, and whether these could be explained by differences in potential determinants of FV intake in 11-year-old Dutch schoolchildren, by comparing two school samples assessed in 2003 and 2009. Methods For 1105 children of the Pro Children study in 2003 and 577 children of the Pro Greens study in 2009 complete data on intake and behavioural determinants were available. The self-administered questionnaire included questions on children's ethnicity, usual fruit and vegetable intake, mother's educational level, and important potential determinants of fruit and vegetable intake. Multiple regression analysis was applied to test for differences in intake and determinants between study samples. Mediation analyses were used to investigate whether the potential mediators explained the differences in intake between the two samples. Results In 2009, more children complied with the World Health Organization recommendation of 400 g fruit and vegetables per day (17.0% than in 2003 (11.8%, p = 0.004. Fruit consumption was significantly higher in the sample of 2009 than in the sample of 2003 (difference = 23.8 (95%CI: 8.1; 39.5 grams/day. This difference was mainly explained by a difference in the parental demand regarding their child's intake (23.6%, followed by the child's knowledge of the fruit recommendation (14.2% and parental facilitation of consumption (18.5%. Vegetable intake was lower in the 2009 sample than in the 2003 sample (12.3 (95%CI -21.0; -3.6. This difference could not be explained by the assessed mediators. Conclusions The findings indicate that fruit intake among 11-year-olds improved somewhat between 2003 and 2009. Vegetable intake, however, appears to have declined somewhat between 2003 and 2009. Since a better knowledge of the recommendation, parental demand and facilitation explained most of the observed fruit consumption difference, future interventions may specifically address these potential mediators. Further, the provision of vegetables in the school setting should be considered in order to increase children's vegetable intake.

Fischer Claudia

2011-12-01

219

Refractive index sensing in aqueous environment using three different polymeric waveguide interferometers  

Science.gov (United States)

In this work, the performances of three developed polymer integrated optical sensors based on different waveguide configurations were evaluated for homogeneous refractive index (RI) sensing in aqueous environment. Young interferometer configuration with reference and sensing waveguide arms was utilized in sensor chips. Light from a laser source was end-fire coupled into the chips and interference pattern produced by the out coupled light was investigated. External fluidic pump was used to produce the analyte flow. The homogeneous bulk refractive index change was characterized by applying DI-water with varying glucose concentrations. With an interaction length of 1 cm a detection limit in the order of 10-5 ~ sub-10-6 refractive index unit (RIU) was determined. The sensing performances are compared among the sensors in terms of sensitivity, stability, multiparameter sensing ability, and fabrication and operation simplicity. The polymeric-inorganic composited rib waveguide configuration showed the highest performance and relatively simple fabrication process amongst the evaluated sensors.

Wang, Meng; Hiltunen, Jussi; Myllylä, Risto

2013-05-01

220

The regularities of mutagenic action of ?-radiation on vegetative Bacillus subtilis cells with different repair genotype  

International Nuclear Information System (INIS)

The regularities of induction of his"-?his"+ mutations in vegetative Bacillus subtilis cells with different repair capacity after ?-irradiation have been studied. The wild type cells, polAl, recE4, recA, recP, add5, recH were used in experiments. It was shown that radiation-induced mutagenesis is determined by a repair genotype of cells. The blocking of different reparation genes is reflected on mutagenesis ratio by various ways. A frequency of induction mutations in polA strain is higher than in wild type cells and it is characterized by the linearly-quadratic dose curve. The different rec"- strains that belong to various epistatic groups reveal an unequal mutation induction. The add5 and recP strains are characterized by the high-level induction mutations in contrast with the wild type cells. The mutagenesis in recE and recH strains, on the contrary, sharply reduces. The different influence of rec genes inhering to various epistatic groups on mutagenesis in Bacillus subtilis cells probably reflects the complex organization of their SOS repair system. (author)

2000-01-01

 
 
 
 
221

Composition, peat-forming vegetation and kerogen paraffinicity of Cenozoic coals: Relationship to variations in the petroleum generation potential (Hydrogen Index)  

Energy Technology Data Exchange (ETDEWEB)

Coals with similar thermal maturity and from the same deposit normally show a considerable range in petroleum generation potential as measured by the Hydrogen Index (HI). This variation may partly be related to variations in plant input to the precursor mires and organic matter preservation. It is widely accepted that some Cenozoic coals and coaly sediments have the potential to generate oil, which is related to the coal's paraffinicity. Coal paraffinicity is not readily reflected in the bulk HI. In this paper, the relationships between measured HI and coal composition, coal kerogen paraffinicity and floral input have been investigated in detail for three sets of coals from Colombia/Venezuela, Indonesia, and Vietnam. The samples in each coal set are largely of iso-rank. The petroleum generation potential was determined by Rock-Eval pyrolysis. Reflected light microscopy was used to analyse the organic matter (maceral) composition and the thermal maturity was determined by vitrinite reflectance (VR) measurements. The botanical affinity of pollen and spores was analysed by palynology. Coal kerogen paraffinicity was determined by ruthenium tetroxide-catalysed oxidation (RTCO) followed by chain length analysis and quantification (mg/g TOC) of the liberated aliphatic chains. The coals are dominated by huminite, in particular detrohuminite. Only the Vietnamese coals are rich in microscopically visible liptinite. The pollen and spores suggest that the coals were derived principally from complex angiosperm mire vegetations, with subordinate proportions of ferns that generally grew in a subtropical to tropical climate. Measured HI values vary considerably, but for the majority of the coals the values lie between approximately 200 mg HC/g TOC and 300 mg HC/g TOC. Aliphatics yielding monocarboxylic acids dominate in the coal kerogen, whereas aliphatics yielding dicarboxylic acids are secondary. However, the dicarboxylic acids show that cross-linking long-chain aliphatics are present in the kerogen structure. All studied coals are paraffinic with C{sub 19-35} aliphatic chains in the kerogen, and the aliphatics in the range C{sub 25-35} show that the coals may have the potential to generate waxy crude oil. The Indonesian coals are richest in long-chain aliphatics and are thus potentially most oil-prone. Multivariate statistical analysis shows that for the present three sample sets variations in HI are positively correlated to different combinations of the C{sub 10+} aliphatic chains in the kerogen and the amount of detrohuminite + liptodetrinite and liptinite. Furthermore, part of the HI can be attributed to hydrogen in compounds with less than 10 carbon atoms, which is the lowest alkyl detected by RTCO analysis, thus representing a potential for generation of gas and light liquid hydrocarbons. The measured HI is therefore not always a good indicator for humic coal's potential to source waxy oil. Vegetational influence (palynology) on the variation of HI cannot be shown within the investigated span of variance and for the present coals. However, it is likely that some of the range in measured HI values is caused by floral vairiations not revealed by the palynological analysis and to variations in the preservation of the organic matter. (author)

Petersen, H.I.; Lindstroem, S.; Nytoft, H.P.; Rosenberg, P. [Geological Survey of Denmark and Greenland (GEUS), Oester Voldgade 10, DK-1350 Copenhagen (Denmark)

2009-04-01

222

Comparison Between Fractional Vegetation Cover Retrievals from Vegetation Indices and Spectral Mixture Analysis: Case Study of PROBA/CHRIS Data Over an Agricultural Area  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper we compare two different methodologies for Fractional Vegetation Cover (FVC) retrieval from Compact High Resolution Imaging Spectrometer (CHRIS) data onboard the European Space Agency (ESA) Project for On-Board Autonomy (PROBA) platform. The first methodology is based on empirical approaches using Vegetation Indices (VIs), in particular the Normalized Difference Vegetation Index (NDVI) and the Variable Atmospherically Resistant Index (VARI). The second methodology is based on th...

Jime?nez-mun?oz, Juan C.; Sobrino, Jose? A.; Antonio Plaza; Luis Guanter; José Moreno; Pablo Martinez

2009-01-01

223

Different Disinfectants Efficiency of Fruits and Vegetables Available in Market of Kermanshah  

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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.

Ali Almasi

2013-12-01

224

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

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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.

Moreira Leila B

2010-11-01

225

The trend of indexed papers in PubMed covering different aspects of self-immolation.  

Science.gov (United States)

Self-immolation is a fatal and devastating method of committing suicide used around the world. The chief aim of the present article is to look at the trend of indexed papers in PubMed covering different aspects of self-immolation. PubMed search engine (http://www.ncbi.nlm.nih.gov) was searched by using six keywords i.e. "self-immolation", "self-inflicted burn", "self-burning", "self-incineration", "suicidal burns" and "suicide by burning". These keywords should appear either in the title or the abstract of the articles. The time frame was set as to retrieve papers expanding from early indexing time up to end of the year 2011. Based on the search strategy 132 papers were retrieved from these total numbers; 12 (9%) were categorized as review papers; 24 (18%) as case reports and the rest 96 (73%) were original studies. It seems that the number of papers increased during the years of investigations and the highest indexed papers i.e. 14 (10.6%) belonged to the year 2011. While most journals, published only one article the highest indexed papers i.e. 35 (26.5%) belonged to Burns. There was an increasing trend in the number of self-immolation articles indexed in PubMed since 1965. Three journals i.e. Burns, Journal of Burn Care and Rehabilitation and Journal of Forensic Sciences hosted for more than 37% of all those indexed articles. However, given the increasing trend of self-immolation still more studies are needed to shed light on the diverse aspects of this appalling human behavior. PMID:24659075

Rezaeian, Mohsen

2014-01-01

226

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

DEFF Research Database (Denmark)

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 â??green fishâ? 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.

Hyldig, Grethe; Nielsen, Henrik Hauch

227

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.

2012-08-01

228

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

229

Caracterización del efecto de estrés usando índices espectrales de la vegetación para la estimación de variables relacionadas con la biomasa del área / Characterization of stress effect using spectral vegetation indexes for the estimate of variables related to aerial biomass  

Scientific Electronic Library Online (English)

Full Text Available SciELO Mexico | Language: Spanish Abstract in spanish El uso de índices espectrales o IV de la vegetación, basados en las líneas iso-IAF en el espacio espectral del rojo (R) e infrarrojo cercano (IRC), plantea relaciones diferentes en las etapas vegetativas y de senescencia con variables biofísicas como la biomasa aérea o Bm, el índice de área foliar o [...] IAF o la cobertura aérea de la vegetación o fv. Con el índice FVIS basado en las líneas iso-suelo del espacio R-IRC, los patrones temporales pueden identificarse mediante un modelo expo-lineal y exponencial. Así, las pendientes para la etapa vegetativa y de senescencia pueden usarse para cuantificar el nivel de estrés utilizando el concepto de equivalencia ambiental. Este esquema de caracterización fue analizado con mediciones radiométricas y de fv en cultivos de fríjol (Phaseolus vulgaris L.), garbanzo (Cicer arietinum L.), cártamo (Carthamus tinctorius, L.), sorgo (Sorghum bicolor, L. Moench) y trigo (Triticum spec. L.), del Valle del Yaqui, estado de Sonora, México. Los resultados obtenidos soportan la aproximación de caracterización planteada para el nivel de estrés. Abstract in english The use of spectral indexes or vegetation VI, based on iso-LAI lines in the spectral space of red (R) and near infrared (NIR), presents different relations in vegetative and senescence periods with biophysical variables such as aerial biomass or Bm, the index of foliar area or LAI, or aerial vegetat [...] ion cover or fv. With the ISVI index based on iso-soil lines of the R-NIR space, the temporal patterns may be identified by an expo-linear and exponential model. Thus, the slopes for the vegetative phase and for senescence can be used to quantify the stress level utilizing the concept of environmental equivalence. This scheme of characterization was analyzed with radiometric and fv measurements in crops of bean (Phaseolus vulgaris L.), chickpea (Cicer arietinum. L.), safflower (Carthamus tinctorius L.), sorghum (Sorghum bicolor, L. Moench), and wheat (Triticum spec. L.) of the Valle del Yaqui, State of Sonora, México. The obtained results support the approximation of the characterization proposed for the stress level.

Marisol, Reyes; Fernando, Paz; Marcos, Casiano; Fermín, Pascual; M. Isabel, Marín; Enrique, Rubiños.

230

A STUDY ON VARIATION IN BIOCHEMICAL ASPECTS OF DIFFERENT TREE SPECIES WITH TOLERANCE AND PERFORMANCE INDEX  

Directory of Open Access Journals (Sweden)

Full Text Available The present study was undertaken to evaluate the variation between biochemical characteristics and air pollution tolerance index (APTI of 6 different plant species. The results of the present study indicate that APTI was significantly correlated with total chlorophyll, ascorbic acid, leaf pH for all species and are the most significant and determining factors on which the tolerance depends. The order of tolerance index of plant species is as follows Saraca indica (13.71, Azadirachta indica (12.98, Shorea robusta (12.64, Eucalyptus sp. (12.61, Ficus religiosa (12.61 and Tectona grandis (13.33. According to anticipated performance index (API all species were tolerant i.e. Azadirachta indica, Ficus religiosa, Saraca indica, Tectona grandis (75%, Shorea robusta and Tectona grandis (68%. The present study suggests that evaluation of plant tolerance and performance index might be very useful in the selection of appropriate species which can be expected to perform well for the development of green environment.

MEHA BORA

2014-03-01

231

Determination of the level of certain trace elements in vegetables in differently contaminated regions  

Energy Technology Data Exchange (ETDEWEB)

The aim of the investigations was the determination of the lead, cadmium, copper, iron, zinc and magnesium content in some vegetables in an industrial region (Cracow) and in an agricultural region far from industrial centres (control). It was found that all the vegetables analysed contained lead and cadmium contaminations. The average lead concentration in parsley-haulm and parsley-root and cadmium concentration in beets, onion, parsley-haulm, leek, lettuce and potatoes coming from the Cracow region exceeded the permissible norm. In the vegetables from the Cracow region the levels of the determined trace elements were higher (P < 0.01) than that of the controls. (orig.)

Krelowska-Kulas, M. (Dept. of Food Commodity Science, Academy of Economics, Cracow (Poland))

1993-01-01

232

LEAF AREA INDEX IN WINTER WHEAT: RESPONSE ON SEED RATE AND NITROGEN APPLICATION BY DIFFERENT VARIETIES  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 fro...

Bavec, M.; Vukovic?, K.; Grobelnik, S.; ? ROZMAN; Bavec, F.

2007-01-01

233

Refractive index gradient diagnostics: analysis of different optical systems and application to COBRA ion diode  

International Nuclear Information System (INIS)

Different optical system variations for refractive index gradient diagnostics with a laser beam probe have been analyzed. A 'three-telescope' optical system which permits simultaneous measurement of both the laser beam centroid deflection by a bi-cell photodiode and the spatial Fourier spectrum of the deflected beam by a streak camera has been implemented on the COBRA ion diode. The dynamics of the anode plasma layer was studied with these techniques. (author). 3 figs., 8 refs

1996-06-10

234

[Relationship of evaluation indexes of sludge dewatering performance under different conditioning programs].  

Science.gov (United States)

Performances of different sludge conditioners are difficult to evaluate due to the use of various evaluation indexes. Taking several traditional sludge conditioners, e.g. PAM, FeCl3 and inorganic composite conditioners as examples and five evaluation indexes include specific resistance to filtration (SRF), capillary suction time (CST), sludge settling performance, water content of sludge cake and dewatering efficiency, were investigated respectively in order to study the correlation among those indexes. The results indicate a significant positive linear correlation between SRF and CST (R2 values are 0.96 and 0.93, respectively) after adding different types of conditioners or different amount of conditioners. While they can precisely reflect plate and frame filter press efficiency, but they fail to predict the effects of centrifugal dewatering. Sludge settling performance presents the similar tendencies with SRF and CST. Since there is only limited correlation rather than strict correspondence between water content of sludge cake and dewatering efficiency. Thus, both factors should be considered synthetically in optimizing dosage performances. PMID:22295640

Liu, Huan; Yang, Jia-Kuan; Shi, Ya-Fei; Li, Ye; He, Shu

2011-11-01

235

A Multivariate Index for the Atlantic Intertropical Convergence Zone: sensitivity tests to different set of variables  

Science.gov (United States)

A multivariate index based on the first combined EOF (EOFc) of anomalies of precipitation (P), zonal (u) and meridional (v) wind's components, specific humidity (q), and air temperature (T) at 850 mb is proposed in order to characterize the convection's intensity, position, and variability of the Atlantic Intertropical Convergence Zone (ITCZ) on intraseasonal to interannual timescales. The EOFc's spatial domain encompassed tropical South America, tropical Atlantic Ocean and part of western Africa. Similar index was described in Silva and Carvalho (2007) to characterize the South American monsoon. Sensitivity tests were performed in order to investigate the importance of excluding variables in the index's calculation. One or more variables were excluded of the analysis at each computation (Table 1). The first EOFc using all the variables explains 22% of the total variance. The variance increases to 24% when the variables u, v, q, and T are considered in the computation. The variance is 22% when the EOFc is calculated using four variables (P, u, v, T). Since P and q are correlated, using both variables is redundant. Since the first EOFc explains 24% of the variance using the variables u, v, q, and T, it is concluded that precipitation is not necessary in the index's calculation. Using fewer variables does not have a significant impact in the explained variance, even when the second EOFc is considered. An index based only on precipitation is not efficient in characterizing the activity and variability of the ITCZ.Table 1 - Explained variance (%) for EOFc-1 and EOFc-2 performed with different set of variables.t;

Nóbile Tomaziello, A.; Gandu, A. W.; Carvalho, L. V.

2012-12-01

236

Site index based on site characteristics for black spruce and paper birch in Quebec - possible improvement by collecting vegetation indicators  

Energy Technology Data Exchange (ETDEWEB)

Data sampled in Quebec consisting partly of data from an ecological inventory and partly of stand data of Black spruce (Picea mariana) and Paper birch (Betula papyrifera) were analyzed in order to establish site index functions with site characteristics. Swedish material was analyzed to investigate the possibilities of improving the accuracy by data on indicator species from the understorey. For Quebec the largest multiple correlation coefficient was obtained within the ecological regions up to 800 meters of altitude. At the best, the standard deviation about the function was 1.58 meters for Black spruce and 1.51 meters for Paper birch. Overall, the correlation is low, but the literature review shows similar results in other studies. Relationships can be established with data from the ecological inventory and an improvement can be achieved with information about indicator species Examination paper 1997-8. 38 refs, 3 figs, 10 tabs

Kallin, Anna

1997-12-31

237

Characteristics of Photosynthetic Behaviors and Chlorophyll Fluorescence in Different Vegetable Species  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This study investigated the variability in the various physiological characteristics of seven popular commercial vegetable seedlings such as cabbage, spinach, Chinese cabbage, eggplant cucumber, tomato and Chinese radish. The photosynthetic rate (Pn) was higher in cabbage seedlings followed by eggplant seedlings. Chinese cabbage and cabbage seedlings showed higher stomatal conductance (CS) than other vegetables studied. Cucumber seedlings had higher respiration rate followed by tomato, egg pl...

Sharmin Khan; Yuichi Yoshida; Shahidul Islam

2006-01-01

238

Índice de seleção e estimativa de parâmetros genéticos e fenotípicos para características relacionadas com a produção de milho-verde / Index of selection and estimation of genetic and phenotypical parameters for traits related with the production of vegetable corn  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese O Brasil é um dos maiores produtores de milho do mundo e possui grande potencial para a produção de milho verde. Além de agregar valor ao produto, a comercialização de milho verde cresceu muito nos últimos anos. Há escassez de informações sobre a avaliação e a obtenção de cultivares destinadas à pro [...] dução de milho-verde e também sobre estudos genéticos das características envolvidas nessa produção. Objetivou-se, neste trabalho, estimar parâmetros genéticos e fenotípicos, a correlação genética, classificar e identificar híbridos de milho verde promissores ao mercado consumidor e avaliar a eficiência dos pesos econômicos atribuídos. Os resultados determinaram que a seleção terá sucesso, para as diferentes características de milho-verde, pois, a herdabilidade foi de alta magnitude para as características avaliadas. A avaliação da produtividade de espigas empalhadas (PEE) é suficiente para definir quais os híbridos apresentam o melhor desempenho para a produtividade de espigas comerciais (PEC), diâmetro (DIAM) e comprimento de espigas (COMP). Isso indica que as características PEC, DIAM e COMP podem ser descartadas da avaliação em programas de melhoramento de milho-verde. Os híbridos HS48, HS27, HS24, HS25, HS12 e HS45 acumularam um maior número de características desejadas em um único genótipo, com base no índice de seleção baseado na soma de postos, sendo os mais promissores para a produção de milho-verde. Os pesos econômicos utilizados foram capazes de distinguir e identificar os híbridos mais promissores para a produção de milho- verde e podem ser utilizados como critério de seleção em programas de melhoramento de milho-verde. Abstract in english Brazil is one of the largest producers of corn of the world and it possesses great potential for vegetable corn production. Besides adding value to the product, the commercialization of vegetable corn increased in the last years. There is shortage of information about the evaluation and the acquisit [...] ion of genotypes destined to the production of vegetable corn and also on genetic studies of the traits involved in this production. The objective of this work was to estimate the genetic and phenotypic parameters, and the genetic correlation, and to classify and identify hybrids of promising vegetable corn to the consumer market and to evaluate the efficiency of the attributed economical weights. The results determined that the selection will succeed, for the different traits of vegetable corn, because the heritability was of high magnitude to the appraised traits. Evaluation of husked ears yield (PEE) was enough to define which hybrid presents better commercial ear productivity, diameter and corn ear length. This indicates that those traits could be discarded in the selection process of genotypes of breeding programs for vegetable corn production. The hybrids HS48, HS27, HS24, HS25 and HS12 accumulated the largest number of desirable traits in a single genotype based on the sum of rank index. The used economical weights were efficient to distinguish and identify the most promising hybrid for vegetable corn production and they can be used as a selection criterion in programs of breeding of vegetable corn.

Fabricio, Rodrigues; Renzo Garcia, Von Pinho; Carlos Juliano Brant, Albuquerque; Édila Vilela Resende, Von Pinho.

239

Índice de seleção e estimativa de parâmetros genéticos e fenotípicos para características relacionadas com a produção de milho-verde Index of selection and estimation of genetic and phenotypical parameters for traits related with the production of vegetable corn  

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Full Text Available O Brasil é um dos maiores produtores de milho do mundo e possui grande potencial para a produção de milho verde. Além de agregar valor ao produto, a comercialização de milho verde cresceu muito nos últimos anos. Há escassez de informações sobre a avaliação e a obtenção de cultivares destinadas à produção de milho-verde e também sobre estudos genéticos das características envolvidas nessa produção. Objetivou-se, neste trabalho, estimar parâmetros genéticos e fenotípicos, a correlação genética, classificar e identificar híbridos de milho verde promissores ao mercado consumidor e avaliar a eficiência dos pesos econômicos atribuídos. Os resultados determinaram que a seleção terá sucesso, para as diferentes características de milho-verde, pois, a herdabilidade foi de alta magnitude para as características avaliadas. A avaliação da produtividade de espigas empalhadas (PEE é suficiente para definir quais os híbridos apresentam o melhor desempenho para a produtividade de espigas comerciais (PEC, diâmetro (DIAM e comprimento de espigas (COMP. Isso indica que as características PEC, DIAM e COMP podem ser descartadas da avaliação em programas de melhoramento de milho-verde. Os híbridos HS48, HS27, HS24, HS25, HS12 e HS45 acumularam um maior número de características desejadas em um único genótipo, com base no índice de seleção baseado na soma de postos, sendo os mais promissores para a produção de milho-verde. Os pesos econômicos utilizados foram capazes de distinguir e identificar os híbridos mais promissores para a produção de milho- verde e podem ser utilizados como critério de seleção em programas de melhoramento de milho-verde.Brazil is one of the largest producers of corn of the world and it possesses great potential for vegetable corn production. Besides adding value to the product, the commercialization of vegetable corn increased in the last years. There is shortage of information about the evaluation and the acquisition of genotypes destined to the production of vegetable corn and also on genetic studies of the traits involved in this production. The objective of this work was to estimate the genetic and phenotypic parameters, and the genetic correlation, and to classify and identify hybrids of promising vegetable corn to the consumer market and to evaluate the efficiency of the attributed economical weights. The results determined that the selection will succeed, for the different traits of vegetable corn, because the heritability was of high magnitude to the appraised traits. Evaluation of husked ears yield (PEE was enough to define which hybrid presents better commercial ear productivity, diameter and corn ear length. This indicates that those traits could be discarded in the selection process of genotypes of breeding programs for vegetable corn production. The hybrids HS48, HS27, HS24, HS25 and HS12 accumulated the largest number of desirable traits in a single genotype based on the sum of rank index. The used economical weights were efficient to distinguish and identify the most promising hybrid for vegetable corn production and they can be used as a selection criterion in programs of breeding of vegetable corn.

Fabricio Rodrigues

2011-04-01

240

Influence of different planting seasons of six leaf vegetables on residues of five pesticides.  

Science.gov (United States)

To investigate the influence of different planting seasons on the dissipation of pesticides, field experiments of thiophanate-methyl, metalaxyl, fluazifop-P-butyl, chlorpyrifos, and ?-cyhalothrin on six crops including pakchoi, rape, crown daisy, amaranth, spinach, and lettuce were designed and conducted. In this study, a high-performance liquid chromatography and electrospray ionization-tandem mass spectrometer with multiple reaction monitoring was used to simultaneously determine thiophanate-methyl and its metabolite carbendazim, metalaxyl, and fluazifop-P-butyl in various samples; gas chromatography with an electron capture detector was used to detect chlorpyrifos and ?-cyhalothrin. The limits of quantitation (LOQs) of these six pesticides were in the range of 0.001-0.01 mg kg(-1) for all samples, and the average recoveries of all pesticides ranged from 60.1 to 119.1% at 0.01 and 0.1 mg kg(-1) spiked levels. The relative standard deviation (RSD) ranged from 1.1 to 13.9%. All maximal concentrations of the six pesticides in six leaf vegetables in autumn were higher than in summer in Beijing. For most pesticides half-lives in autumn were longer than in summer. The results showed that the initial concentration, maximal concentration, and half-lives of pesticides were influenced not only by environmental factors such as light, heat, moisture, and rainy climate but also by plant matrices. PMID:23978278

Fan, Sufang; Deng, Kailin; Yu, Chuanshan; Zhao, Pengyue; Bai, Aijuan; Li, Yanjie; Pan, Canping; Li, Xuesheng

2013-09-25

 
 
 
 
241

Influence of Paclobutrazol and Ethephon on Vegetative Growth of Guava (Psidium guajava L.) Plants at Different Spacing  

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To ascertain the growth retarding potential of Paclobutrazol (PBZ) and Ethephon on guava plants at different spacing viz 6×2 m, 6×3 m, 6×4 m and 6×5 m; both were applied at 500 ppm, 1000 ppm as a foliar spray. Investigation revealed that all treatments influence the vegetative growth of plants compared to untreated plants at all spacing levels. However, paclobutrazol considerably restrict the overall vegetative growth of trees. Stock and scion girth was found to be increased with ethephon...

2010-01-01

242

Effects of adding bentonite to different substrates on vegetative growth and yield of snap beans (Phaseulus vulgaris L.  

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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.

P. Aghdak

2010-12-01

243

Evaluation of Effluent Quality Used for Irrigation of Vegetable Production in Different Districts of Potowar, Pakistan  

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Full Text Available 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 to 4.36 showing that all the samples were low in Na contents. RSC varied from 0.0-8.1 mmol L-1 in the sewage samples under study; 59% of the samples had < 2.0 mmol L-1 of RSC showing that sewage represented by these samples had no risk of NaHCO3 hazard when applied to soils. Chloride contents in the samples were in the range of 0.5 to 4.7 mmol L-1 and were within safe limits. Zn and Pb contents in the sewage of various locations were found within safe limits (< 2.0 and 5.0 mg L-1, respectively while Cu, Cd, Ni and Cr concentrations were found to exceed the maximum permissible limits. The effluent of areas under investigation are mixture of both domestic and industrial wastewater, high levels of HCO3- from washing soaps and detergents and excess of heavy metals from different industrial sources were present in the effluent. Therefore, sewage irrigation may cause deterioration of soil quality by causing salinity and introducing excessive contents of HCO3- in soils and poses health hazards by increasing heavy metal contents in vegetables and crops.

Tahir Hussain Chattha

2005-01-01

244

The relationship between phytomass, NDVI and vegetation communities on Svalbard  

Science.gov (United States)

Several studies have shown a close relationship between vegetation fertility and different vegetation indices extracted from satellite data. The vegetation fertility in Arctic is at overall scales highly related to temperature. At lower scales surface material, snow cover, hydrology and anthropogenic effects (geese, reindeer) are determinant in constituting the different vegetation communities. The extent and occurrence of different vegetation communities are expressed in vegetation maps. On Svalbard a vegetation map covering the entire archipelago has recently been developed. The map is differentiated into 18 map units showing large areas of non- and sparsely vegetated ground. The most favorable vegetation is seen as productive marshes and moss tundra communities in the lowland. Various mathematical combinations of spectral channels in satellite images have been applied as sensitive indicators of the presence and condition of green vegetation. Today the normalized difference vegetation index (NDVI) is mostly used to display this information. NDVI is an indicator of the density of chlorophyll in leaf tissue calculated from the red and near infrared bands: NDVI = (NIR - RED)/(NIR + RED). NDVI gives values between -1 and +1 where vegetated areas in general yield high positive values, while non-vegetated ground is found on the negative side.

Johansen, Bernt; Tømmervik, Hans

2014-04-01

245

THE INFLUENCE OF NAPHTHALENE ACETIC ACID (NAA IN ROOTING OF THE DIFFERENT VEGETATIVE CUTTINGS OF THUYA OCCIDENTALIS “EMERAUD”  

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Full Text Available Thuya occidentalis “Emeraud” (Thuya ssp, is one of the most used evergreen ornamental plants for decoration of parks and gardens with very slow growth. They form few seeds with relatively low germination. This is the cause of the continuous efforts to find efficient ways of vegetative propagation, which influence the increase of the coefficient of thuya’s propagation. The paper presents the influence of the naphthalene acetic acid (NAA 4000 ppm in the rooting of one year vegetative cuttings of Thuya occidentalis “Emeraud”, with and without biennial wood. The experiment was carried out during three consecutive years, 2008-2010, in the flower’s greenhouse of the Experimental Centre of the Department of Horticulture at Agricultural University of Tirana. The one year vegetative cuttings were prepared as simple cuttings (cuttings without bark or biennial wood and cuttings with the scion (cuttings with bark or biennial wood. Vegetative cuttings of thuya were sown in the perlite band. Control for the final rooted seedlings and/or rooting percentage was carried out 60 days after sowing of the vegetative cuttings in the perlite band. There was calculated the rooting percentage of the vegetative cuttings treated and untreated with NAA 4000 ppm. The results show that the average rooting percentage of the simple untreated cuttings was 20%, while the average rooting percentage of the untreated cuttings with a scion was 45%. Total rooting percentage of the untreated cuttings was 32.5%. So, cuttings with a scion (the cuttings with bark and biennial wood, have a higher rooting percentage even when they are not treated with NAA. There were observed significant differences of the results in the case of treating cuttings with the rooting hormone NAA, 4000 ppm. These differences consisted in increasing the rooting ability and the rooting percentage of the cuttings. The average rooting percentage of the simple untreated cuttings with NAA was 51%, while the mean percentage of the cuttings with a scion treated with NAA was 80%. The total rooting percentage of the untreated cuttings was 65.5%. The use of the rooting hormone NAA, 4000 ppm, for the treatment of the one year vegetative cuttings of thuya was followed by the significant increases the rooting percentage in total from 32.5% to 65.5%. The three-year-results showed that the use of the rooting hormone NAA, 4000 ppm, does affect significantly in the increase of the rooting percentage of the vegetative cuttings, up to 30%, as well as in doubling the quantity of the seedling produced for each planting season, which was confirmed by ANOVA.

Esmeralda Sherko

2011-12-01

246

Analysis of Vegetation Behavior in a North African Semi-Arid Region, Using SPOT-VEGETATION NDVI Data  

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Full Text Available The analysis of vegetation dynamics is essential in semi-arid regions, in particular because of the frequent occurrence of long periods of drought. In this paper, multi-temporal series of the Normalized Difference of Vegetation Index (NDVI, derived from SPOT-VEGETATION satellite data between September 1998 and June 2010, were used to analyze the vegetation dynamics over the semi-arid central region of Tunisia. A study of the persistence of three types of vegetation (pastures, annual agriculture and olive trees is proposed using fractal analysis, in order to gain insight into the stability/instability of vegetation dynamics. In order to estimate the state of vegetation cover stress, we propose evaluating the properties of an index referred to as the Vegetation Anomaly Index (VAI. A positive VAI indicates high vegetation dynamics, whereas a negative VAI indicates the presence of vegetation stress. The VAI is tested for the above three types of vegetation, during the study period from 1998 to 2010, and is compared with other drought indices. The VAI is found to be strongly correlated with precipitation.

Abdelghani Chehbouni

2011-11-01

247

A tobacco cDNA reveals two different transcription patterns in vegetative and reproductive organs  

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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.

Silva I. da

2002-01-01

248

A tobacco cDNA reveals two different transcription patterns in vegetative and reproductive organs  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in english 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.

Silva, I. da; Angelo, P.C.S.; Molfetta, J.B.; Ferraz, M.T.; Silva, L.L.P. da; Goldman, G.H.; Goldman, M.H.S..

249

Yield Characteristics of Moringa oleifera Across Different Ecologies in Nigeria as an Index of Its Adaptation to Climate Change  

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Full Text Available The pod and yield characteristics of Moringa oleifera plants grown in Ibadan (Rainforest vegetation, Nsukka (Forest-derived savannah vegetation and Jos (arid derived savannah vegetation were evaluated from 2007- 2009 to assess adaptability of the plant to climate change threats. The rainfall and temperature distribution in the three locations varied over the years. The Moringa oleifera plants grown at Ibadan had the greatest pod and seed yield followed by those at Nsukka and Jos in that order. The annual pod and seed production capacities of the plants differed significantly (p < 0.05 in the different locations. The overall annual pod and seed production per location, including yield characteristics, did not differ significantly throughout the years of study. Moringa oleifera was therefore found to be a suitable crop adaptable to various environmental and climatic changes in Nigeria.

Ndubuaku U. M.

2013-11-01

250

Vegetative Compatibility and Heterokaryon Formation between Different Isolates of Colletotrichum Lindemuthianum by using the nit Mutant System  

Science.gov (United States)

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 subdivide 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.

Rodrigues de Carvalho, Camila; Cristina Mendes-Costa, Maria

2011-01-01

251

Vegetative compatibility and heterokaryon formation between different isolates of Colletotrichum lindemuthianum by using the nit mutant system  

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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 subdivide 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.

Camila Rodrigues de Carvalho

2011-03-01

252

Diversity of Halophyte Desert Vegetation of the Different Saline Habitats in the Valley of Oued Righ, Low Sahara Basin, Algeria  

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The aim of the present study was to investigate the floristic composition and diversity of the different habitat types in the saline areas of the valley of Oued Righ, locating in the low Sahara basin of Algeria. Three distinct saline habitats were examined: saline soil habitats, subsaline soil habitats, and waterlogged habitats. A total of 67 stands along the study area were investigated using the quadrat method, and different vegetation parameters, such as cover, frequency, density, and Impo...

2012-01-01

253

The values of ED50 and therapeutic indexes of different radioprotector groups  

International Nuclear Information System (INIS)

Radioprotective agents were shown to be divided in 3 groups: (1) cystamine, AET, cystaphos, gammaphos, and thiogammaphos with ED50 (the dose that gave a half of the maximal protective effect) of 103-101,6 ?mol/kg and therapeutic index K LD50/ED50 = 100-101,6; (2) 5-methoxythyptamine, phenylephrine, serotonine, and norepinephrine with ED50 101-100 ?mol/kg and K = 101,8-102,6; (3) clonidine and isoprenaline with ED50 = 10-0,5-10-0,8 ?mol/kg and K = 103-104. Possible causes of these differences and advantages of low ED50 and high K were discussed

1992-01-01

254

The Millon Index of Personality Styles Revised (MIPS-R) in Portugal: Gender Differences  

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This study aims to determine whether males and females differ in the personality styles mesured with the Portuguese version of the Millon Index of Personality Styles Revised, MIPS-R (Millon, 2004). The MIPS-R is a 180-item, True/False inventory designed to measure personality styles of normally functioning adults between the ages of 18 and 65+. It is a theory-based inventory, grounded in biosocial and evolutionary theory, and comprises 12 pairs of scales organized into three main areas: Motiv...

2007-01-01

255

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)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese 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.

Fabricio V., Zanzarini; Teresa C. T., Pissarra; Flavia J. C., Brandão; Daniel D. B., Teixeira.

256

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  

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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 ferramentas 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.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 the 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.

Fabricio V. Zanzarini

2013-06-01

257

Evaluation and Refinement of the Environmental Stress Index (ESI) for Different Climatic Conditions and Distances Below and Above Sea Level.  

Science.gov (United States)

This report summarizes the evaluation and refinement of an environmental stress index (ESI) for heat stress assessment. Two independent studies containing two different databases were analyzed in order to evaluate ESI for different climatic conditions and...

D. S. Moran K. B. Pandolf R. R. Gonzalez

2001-01-01

258

Tailoring Messages to Individual Differences in Monitoring-Blunting Styles to Increase Fruit and Vegetable Intake  

Science.gov (United States)

Objective: To examine whether messages matched to individuals' monitoring-blunting coping styles (MBCS) are more effective in increasing fruit and vegetable intake than mismatched messages. MBCS refers to the tendency to either attend to and amplify, or distract oneself from and minimize threatening information. Design/Setting: Randomly assigned…

Williams-Piehota, Pamela; Latimer, Amy E.; Katulak, Nicole A.; Cox, Ashley; Silvera, Stephanie A. N.; Mowad, Linda; Salovey, Peter

2009-01-01

259

Energy partitioning and environmental influence factors in different vegetation types in the GEWEX Asian Monsoon Experiment  

Science.gov (United States)

Environmental influences upon energy balance in areas of different vegetation types (i.e., forest at Kog-Ma in Thailand and at Yakutsk in Russia, grassland at Amdo in Chinese Tibet and at Arvaikheer in Mongolia, and mixed farmland at Tak in Thailand) in the GEWEX Asian Monsoon Experiment were investigated. The sites we investigated are geographically and climatologically different; and consequently had quite large variations in temperature (T), water vapor pressure deficit (VPD), soil moisture (SM), and precipitation (PPT). During May-October, the net radiation flux (R n) (in W·m-2) was 406.21 at Tak, 365.57 at Kog-Ma, 390.97 at Amdo, 316.65 at Arvaikheer, and 287.10 at Yakutsk. During the growing period, the R n partitioned into latent heat flux (?E/R n) was greater than that partitioned into sensible heat flux (H/R n) at Tak and at Kog-Ma. In contrast, ?E/R n was lower than H/R n at Arvaikheer, H/R n was less than ?E/R n between DOY 149 and DOY 270 at Amdo, and between DOY 165 and DOY 235 at Yakutsk. The R n partitioned into ground heat flux was generally less than 0.15. The short-wave albedo was 0.12, 0.18, and 0.20 at the forest, mixed land, and grass sites, respectively. At an hourly scale, energy partitions had no correlation with environmental factors, based on average summer halfhourly values. At a seasonal scale energy partitions were linearly correlated (usually p<0.05) with T, VPD, and SM. The ?E/R n increased with increases in SM, T, and VPD at forest areas. At mixed farmlands, ?E/R n generally had positive correlations with SM, T, and VPD, but was restrained at extremely high values of VPD and T. At grasslands, ?E/R n was enhanced with increases of SM and T, but was decreased with VPD.

Liu, Fengshan; Tao, Fulu; Li, Shenggong; Zhang, Shuai; Xiao, Dengpan; Wang, Meng

2014-04-01

260

Oxidative changes during ice storage of rainbow trout (Oncorhynchus mykiss) fed different ratios of marine and vegetable feed ingredients  

DEFF Research Database (Denmark)

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 levels of marine oil and proteins vs. vegetable oil and protein. Fish fillets were characterised by measurement of fatty acid and amino acid composition, primary and secondary lipid oxidation products, astaxanthin and tocopherol content. Protein oxidation was assessed by measuring protein carbonyl content, oxidised amino acids, sulfhydryl groups and immuno-blotting against carbonyl groups. Feeding regimes significantly influenced fatty acid composition. Replacement of fish oil with vegetable oil reduced formation of primary oxidation products, but the effect on secondary oxidation products differed between different types of volatiles. The differences in protein and amino acid composition were not significant, and there were no clear effects of diets on protein oxidation, but data indicated that compounds present in the marine ingredients might have had an effect on protein oxidation.

Timm Heinrich, Maike; Baron, Caroline P.

2013-01-01

 
 
 
 
261

Oxidative changes during ice storage of rainbow trout (Oncorhynchus mykiss) fed different ratios of marine and vegetable feed ingredients.  

Science.gov (United States)

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 levels of marine oil and proteins vs. vegetable oil and protein. Fish fillets were characterised by measurement of fatty acid and amino acid composition, primary and secondary lipid oxidation products, astaxanthin and tocopherol content. Protein oxidation was assessed by measuring protein carbonyl content, oxidised amino acids, sulfhydryl groups and immuno-blotting against carbonyl groups. Feeding regimes significantly influenced fatty acid composition. Replacement of fish oil with vegetable oil reduced formation of primary oxidation products, but the effect on secondary oxidation products differed between different types of volatiles. The differences in protein and amino acid composition were not significant, and there were no clear effects of diets on protein oxidation, but data indicated that compounds present in the marine ingredients might have had an effect on protein oxidation. PMID:23194517

Timm-Heinrich, Maike; Eymard, Sylvie; Baron, Caroline P; Nielsen, Henrik Hauch; Jacobsen, Charlotte

2013-02-15

262

Vegetation spatial variability and its effect on vegetation indices  

Science.gov (United States)

Landsat MSS data were used to simulate low resolution satellite data, such as NOAA AVHRR, to quantify the fractional vegetation cover within a pixel and relate the fractional cover to the normalized difference vegetation index (NDVI) and the simple ratio (SR). The MSS data were converted to radiances from which the NDVI and SR values for the simulated pixels were determined. Each simulated pixel was divided into clusters using an unsupervised classification program. Spatial and spectral analysis provided a means of combining clusters representing similar surface characteristics into vegetated and non-vegetated areas. Analysis showed an average error of 12.7 per cent in determining these areas. NDVI values less than 0.3 represented fractional vegetated areas of 5 per cent or less, while a value of 0.7 or higher represented fractional vegetated areas greater than 80 per cent. Regression analysis showed a strong linear relation between fractional vegetation area and the NDVI and SR values; correlation values were 0.89 and 0.95 respectively. The range of NDVI values calculated from the MSS data agrees well with field studies.

Ormsby, J. P.; Choudhury, B. J.; Owe, M.

1987-01-01

263

Heavy Metals Levels in Soil and Vegetables in Different Growing Systems  

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Full Text Available The current project deals with an issue of actuality and scientific/technical necessity and aims to assess the factors contributing to the vulnerability of ecological systems and therefore endangering/compromising food safety. The goals of this ongoing study are to address the main risk factors on ecological system with particular regards to fresh growing vegetables and to establish technical monitoring system(s with a view to increase food safety. Herein, the authors present the research results obtained in 2011 in SIECOLEG Project regarding the assessment of some heavy metals (mainly lead, cadmium, cooper, and manganese of 80 samples soils and 25 samples vegetables from some ecological system. The concentrations of heavy metals were measured by Atomic absorption spectrometer (AAS Schimadzu 6300 - with graphite furnace atomizer and autosampler. In soil: lead and cadmium concentrations ranged from 4.51 to 6.58 mg/kg and from 0.14 to 0.4 mg/kg, respectively. Cooper and manganese concentrations ranged from 20.73 to 6.58 mg/kg and from 218.1 to 298.3 mg/kg, respectively. In vegetables (tomatoes, cucumber, peppers, eggplant, cabbage: lead concentrations ranged from 0.0 (tomatoes to 4.35 mg/kg (cabbage; cooper concentrations ranged from 0.2 mg/kg (cucumber to 0.80 mg/kg (eggplant; manganese concentrations ranged from 0.0 mg/kg (tomatoes to 0.60 mg/kg (eggplant. Cadmium was not detected in any of analysed vegetable samples. Under these circumstances, the project intends to demonstrate the extent of this vulnerability and to elaborate measures for controlling and diminishing the effects of the involved factors in order to increase food safety and security for ecological fresh vegetables

Hura C.

2013-04-01

264

Vegetation productivity patterns at high northern latitudes: do different satellite data sets agree?  

Science.gov (United States)

Satellite records of NDVI form the primary data source to study changes in global vegetation productivity in the last three decades. Creating coherent long-term NDVI records from legacy satellite data sets is challenging because of a.o. the influences of orbital drift, sensor degradation, aerosol spikes from volcanic eruptions, and changing instrument design on reflectance measurements. These issues require corrections to reduce uncertainties in long-term NDVI records. We compared depictions of long-term changes in vegetation productivity over high northern latitudes (>50°N), estimated as trends in growing season NDVI of the most widely used global NDVI data sets. These included the AVHRR based GIMMS-NDVI version G data, and its recent successor version 3g, as well as the shorter NDVI records generated from more modern sensors: SeaWiFS, SPOT-VGT, and MODIS, with the data sets from the latter two sensors adjusted to reduce Bidirectional Reflectance Distribution (BRDF) effects. Our analysis reveals both large geographic areas, totaling 40% of the region, where all data sets indicate similar changes in vegetation productivity over their common temporal record (2002-2008), as well as areas where data sets show conflicting patterns. The newer GIMMS data set (version 3g) shows statistically significant (? = 0.05%) increases in vegetation productivity not seen in its predecessor (version g) in >15% of the study area whereas the reverse is very rare (NDVI data sets regarding primary productivity changes, and encourage users to combine the analysis of NDVI time series data with complementary data sources where possible, such as field measurements of growth, mortality, vegetation cover and composition, tree and shrub rings, and carbon dioxide exchange.

Beck, Pieter; Guay, Kevin; Buermann, Wolfgang; Baccini, Alessandro; Goetz, Scott

2014-05-01

265

Arboreal Ant Assemblages Respond Differently to Food Source and Vegetation Physiognomies: a Study in the Brazilian Atlantic Rain Forest  

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Full Text Available This study aimed to analyze assemblages of arboreal ants in different vegetation physiognomies within the Tropical Moist Forest (Atlantic Rain Forest domain. The study was carried out at the Michelin Ecological Reserve, State of Bahia, Northeast of Brazil. We used sardine (protein resource and honey (carbohydrate resource baits to collect ants foraging in three vegetation types: (1 preserved native forest, (2 forest in regeneration (capoeira with many invasive plants and (3 a mixed agroystem of rubber and cocoa tree plantation. We recorded 69 ant species attracted to the baits, 21 of them exclusive to honey bait and 25 exclusive to the sardine baits. The vegetation physiognomies preserved forest and rubber/cacao agrosystem showed higher species richness in relation to the forest in regeneration (capoeira, suggesting that rubber tree plantations can be a good matrix for the maintenance of some ant species typical of the forest matrix. The type of resource used is important for the structuring of the arboreal ant assemblages. The ants that were attracted to protein resources showed a guild composition that is more differentiated between vegetation types that of ants attracted to glucose resources.

Jacques Hubert Charles Delabie

2013-07-01

266

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)

2010-10-01

267

EMG parameters and EEG ? Index change at fatigue period during different types of muscle contraction  

Science.gov (United States)

The purpose of this study is to measure and analyze the characteristics in change of EMG and EEG parameters at muscle fatigue period in participants with different exercise capacity. Twenty participants took part in the tests. They were divided into two groups, Group A (constant exerciser) and Group B (seldom-exerciser). MVC dynamic and 1/3 isometric exercises were performed; EMG and EEG signals were recorded synchronously during different type of muscle contraction. Results indicated that values of MVC, RMS and IEMG in Group A were greater than Group B, but isometric exercise time was shorter than the time of dynamic exercise although its intensity was light. Turning point of IEMG and ? Index occurred synchronously during constant muscle contraction of isometric or dynamic exercise. It is concluded that IEMG turning point may be an indication to justify muscle fatigue. Synchronization of EEG and EMG reflects its common characteristics on its bio-electric change.

Zhang, Li; Zhou, Bin; Song, Gaoqing

2010-10-01

268

Effect of Different Sowing Dates on Seed Index, Lint and Ginning Out-turn of Various Cotton Varieties  

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Full Text Available The field experiment was conducted to study the effects of sowing dates on seed index, lint index and ginning out-turn of three cotton varieties. The study revealed that the sowing dates produced significant difference in above parameters. The sowing on 10th May produced heavier seed index (8.21g, maximum lint index (4.04 g and high ginning Out-turn percent (33.98. Among the genotypes, Rehmani performed better in seed index (8.48g, lint index (4.04g and G.O.T. percent (33.71. It is recommended that for lower part of Sindh, Pakistan, the cotton crop may be planted in early to mid of May month. Very early and delayed sowings reduces cotton crop yield due to change in environmental factors of the region, which in turn affects plant`s life cycle and vigorous growth.

F. C. Oad

2002-01-01

269

Characterization of nonstarch polysaccharides content from different edible organs of some vegetables, determined by GC and HPLC: comparative study.  

Science.gov (United States)

Content and composition of dietary fiber as nonstarch polysaccharides (NSP) was determined in vegetables belonging to different types of edible organs, using GC and HPLC. Samples analyzed were subterranean organs (radish and leek), leaves (celery, swiss chard, and lettuce), stalks (celery, swiss chard, and asparagus), inflorescence (broccoli), and fruits (tomato, green pepper, and marrow). The results indicate that though the monomeric profile is similar in all these samples quantitative differences were found for neutral sugars and uronic acids among samples of the same type of vegetal organ. The NSP values determined using CG method were in good agreement with HPLC method (R(2) = 0.9005). However, arabinose, mannose, and galactose plus rhamnose are more influenced by the analytical method used than the rest of the monomers in nearly all the samples analyzed. Final values of NSP depend on the method used in celery stalks, broccoli, and green pepper. PMID:13129300

Villanueva-Suárez, M J; Redondo-Cuenca, A; Rodríguez-Sevilla, M D; de las Heras Martínez, M

2003-09-24

270

Subtle proteome differences identified between post-dormant vegetative and floral peach buds.  

Science.gov (United States)

Proper development of deciduous tree species, including peach, is accomplished through an annual growth cycle. Freezing avoidance during winter is necessary for tree survival and is achieved by the enclosure of meristems in floral and vegetative buds. To elucidate the role of developmentally regulated protein networks in bud break, proteins of the two bud-types were extracted and analyzed by two-dimensional gel electrophoresis (2-DE). Of the 1107 protein spots that were picked, 475 were identified and annotated assembling the peach bud proteome reference map. The majority of these proteins are involved in stress-response, detoxification, defense, carbohydrate metabolism and energy production. The protein profiles of both bud-types bear high similarity, whereas only 11 proteins were differentially expressed. These proteins were mainly involved in carbon-nitrogen homeostasis/metabolism and certain developmental processes to sustain rapid growth of the newly emerging organs. Among these are enzymes that differentially regulate the levels of H(2)O(2) between floral and vegetative buds, potentially promoting sequential bud-break. Distinct Nucleoside Diphosphate Kinase (NDPK) variants in floral and vegetative buds were detected suggesting the potential role of NDPKs in H(2)O(2)-mediated signaling for post-dormant bud break. This study provides data towards a better understanding of dormancy release and bud break. PMID:21315198

Prassinos, Constantinos; Rigas, Stamatis; Kizis, Dimosthenis; Vlahou, Antonia; Hatzopoulos, Polydefkis

2011-05-01

271

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

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: English Abstract in portuguese 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 stru

Juan José, Neiff; Alicia Poi de, Neiff; Marta B. Canón, Verón.

272

Raman validity for crystallite size La determination on reticulated vitreous carbon with different graphitization index  

International Nuclear Information System (INIS)

The graphitization index provided by X-ray diffraction (XRD) and Raman spectrometry for reticulated vitreous carbon (RVC) substrates, carbonized at different heat treatment temperatures (HTT), is investigated. A systematic study of the dependence between the disorder-induced D and G Raman bands is presented. The crystallite size La was obtained for both X-ray diffraction and Raman spectrometry techniques. Particularly, the validity for La determination, from Raman spectra, is pointed out comparing the commonly used formula based on peaks amplitude ratio (ID/IG) and the recent proposed equation that uses the integrated intensities of D and G bands. The results discrepancy is discussed taken into account the strong contribution of the line broadening presented in carbon materials heat treated below 2000 deg. C

2007-11-15

273

Raman validity for crystallite size La determination on reticulated vitreous carbon with different graphitization index  

Science.gov (United States)

The graphitization index provided by X-ray diffraction (XRD) and Raman spectrometry for reticulated vitreous carbon (RVC) substrates, carbonized at different heat treatment temperatures (HTT), is investigated. A systematic study of the dependence between the disorder-induced D and G Raman bands is presented. The crystallite size La was obtained for both X-ray diffraction and Raman spectrometry techniques. Particularly, the validity for La determination, from Raman spectra, is pointed out comparing the commonly used formula based on peaks amplitude ratio ( ID/ IG) and the recent proposed equation that uses the integrated intensities of D and G bands. The results discrepancy is discussed taken into account the strong contribution of the line broadening presented in carbon materials heat treated below 2000 °C.

Baldan, M. R.; Almeida, E. C.; Azevedo, A. F.; Gonçalves, E. S.; Rezende, M. C.; Ferreira, N. G.

2007-11-01

274

The minimum clinically important difference for EQ-5D index: a critical review.  

Science.gov (United States)

The European Quality of Life-5 Dimensions Questionnaire (EQ-5D) is the most common instrument to value health outcomes under the patient's perspective. Several studies have investigated whether observed changes are meaningful to patients, using a variety of approaches to estimate the minimum clinically important difference (MCID). This study provides an overview of the state of art of the estimation of the MCID for the three-level EQ-5D index based on the UK scoring algorithm, critically assessing the available evidence. The interest in estimation of MCID for the EQ-5D has been increasing in recent years. However, some additional standardization in the estimation procedures may be of value, in order to enhance the ability to make comparisons across measures and disease areas. Further methodological research might also contribute to reducing gaps between theory and practice. PMID:24625040

Coretti, Silvia; Ruggeri, Matteo; McNamee, Paul

2014-04-01

275

Chemical Composition, Fatty Acids Content and Glycemic Index of Two Different Types of Omani Halwa  

Directory of Open Access Journals (Sweden)

Full Text Available The study evaluated the chemical composition, fatty acids contents and Glycemic Index (GI of two different types (white and black of Omani halwa. Representative samples of Omani halwa were collected from the local market. The proximate composition and energy contents of white and black halwa did not vary significantly (p<0.05. The percentage moisture, crude protein, total fat, ash, crude fiber and Nitrogen Free Extract (NFE in white and black halwa were 11.8 and 12.1; 0.28 and 0.44; 13.8 and 12.4; 0.01 and 0.02; 0.15 and 0.05 and 74.0 and 75.0, respectively. The energy values in white and black halwa were 421.3 and 413.4 kcal/100 g, respectively. No significant (p<0.05 differences were observed in the total fatty acids, Saturated Fatty Acids (SFA, Monounsaturated Fatty Acids (MUFA and Polyunsaturated Fatty Acids (PUFA content in both types of Omani halwa. The SFA were present in highest concentration. The proportionate percentages of SFA, MUFA and PUFA in white and black halwa were 64.57, 65.47, 31.28, 30.79, 4.11 and 3.74%, respectively. The average GI and GL values for white and black halwa also did not vary (p<0.05 and were 54.8 and 52.0 and 14 and 13.4, respectively. Although the glycemic index values of Omani halwa fall in low GI category (<55, it should be consumed with caution because of its high fat, in particular of SFA and high sugar contents.

Amanat Ali

2013-01-01

276

Influence of Paclobutrazol and Ethephon on Vegetative Growth of Guava (Psidium guajava L. Plants at Different Spacing  

Directory of Open Access Journals (Sweden)

Full Text Available To ascertain the growth retarding potential of Paclobutrazol (PBZ and Ethephon on guava plants at different spacing viz 6?2 m, 6?3 m, 6?4 m and 6?5 m; both were applied at 500 ppm, 1000 ppm as a foliar spray. Investigation revealed that all treatments influence the vegetative growth of plants compared to untreated plants at all spacing levels. However, paclobutrazol considerably restrict the overall vegetative growth of trees. Stock and scion girth was found to be increased with ethephon treatments. The tree height and E-W tree spread was found to increased with increasing plant density. Similarly, trunk girth in terms of stock and scion girth was also increased with increase in plant spacing. Although, the PBZ 500 ppm markedly restrict the plant growth but it may be further investigated for managing the guava tree canopies under high density planting systems, taking the fruit quality and economic aspects into consideration.

Jaswinder Singh BRAR

2010-09-01

277

Evaluation of the Uptake and Accumulation of Metals by Some Commonly Irrigated Vegetables in Soils Treated with Different Concentrations of these Metals  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The uptake of some trace elements namely, chromium, nickel, cadmium and lead by some vegetables commonly irrigated were studied under glasshouse conditions. Experiments were conducted in plastic pots using some selected vegetables, lettuce (Lactuca sativa), okra (Abelmoschus esculentus) and pepper (Capsicum annum) grown on sandy loam soils treated with different concentrations of these metals. The treatments investigated include zero application (control), 10, 50 a...

Haliru, M.; Ajibola, V. O.; Agbaji, E. B.

2009-01-01

278

Animal performance and fatty acid composition of lambs fed with different vegetable oils  

Digital Repository Infrastructure Vision for European Research (DRIVER)

[EN] Twenty seven lambs were used to investigate the effects of the inclusion of 4% hydrogenated palm oil (HPO) or sunflower oil (SFO) in the concentrate on feed intake, animal performance and fatty acid composition. Animals (16.2±0.27 kg initial weight) were fed concentrate (Control, HPO or SFO) and barley straw ad libitum and slaughtered at 25 kg. Vegetable oils did not affect (P>0.05) feed intake and animal performance. SFO caused an increase (P<0.001) in trans-C18:1 and tended to increa...

2008-01-01

279

Occupational Class Differences in Body Mass Index and Weight Gain in Japan and Finland  

Science.gov (United States)

Background Occupational class differences in body mass index (BMI) have been systematically reported in developed countries, but the studies have mainly focused on white populations consuming a Westernized diet. We compared occupational class differences in BMI and BMI change in Japan and Finland. Methods The baseline surveys were conducted during 1998–1999 among Japanese (n = 4080) and during 2000–2002 among Finnish (n = 8685) public-sector employees. Follow-up surveys were conducted among those still employed, in 2003 (n = 3213) and 2007 (n = 7086), respectively. Occupational class and various explanatory factors were surveyed in the baseline questionnaires. Linear regression models were used for data analysis. Results BMI was higher at baseline and BMI gain was more rapid in Finland than in Japan. In Finland, baseline BMI was lowest among men and women in the highest occupational class and progressively increased to the lowest occupational class; no gradient was found in Japan (country interaction effect, P = 0.020 for men and P < 0.0001 for women). Adjustment for confounding factors reflecting work conditions and health behavior increased the occupational class gradient among Finnish men and women, whereas factors related to social life had no effect. No statistically significant difference in BMI gain was found between occupational classes. Conclusions The occupational class gradient in BMI was strong among Finnish employees but absent among Japanese employees. This suggests that occupational class inequalities in obesity are not inevitable, even in high-income societies.

Silventoinen, Karri; Tatsuse, Takashi; Martikainen, Pekka; Rahkonen, Ossi; Lahelma, Eero; Sekine, Michikazu; Lallukka, Tea

2013-01-01

280

Vegetative and reproductive evaluation of hot peppers under different plastic mulches in poly/plastic tunnel  

International Nuclear Information System (INIS)

Since the beginning of civilization, the man has developed technologies to increase the efficiency of food production. The use of plastic mulch in commercial vegetable production is one of these traditional techniques that have been used for centuries. Studies were conducted to assess the efficacy of plastic mulch on growth and yield of two hot pepper hybrids, viz. Sky Red and Maha in poly/plastic tunnel. The treatments were black plastic mulch, clear plastic mulch and bare soil as control. Both hot pepper hybrids mulched with black plastic showed significantly better vegetative growth (plant height, leaf area etc) and fruit yield. Clear plastic mulch significantly increased soil temperature and reduced the number of days to first flower than black plastic mulch and bare soil. However, fruit yield was higher by 39.56 and 36.49% respectively in both hybrids when they were grown on black and clear plastic mulch as compared to bare soil. Overall results indicated that the use of plastic mulch is an ideal option to maximize hot pepper productivity as well as to extend their production season in poly/plastic tunnels. (author)

2009-01-01

 
 
 
 
281

Fourier transform infrared spectroscopy (FTIR) and multivariate analysis for identification of different vegetable oils used in biodiesel production.  

Science.gov (United States)

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. PMID:23539030

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

2013-01-01

282

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

Directory of Open Access Journals (Sweden)

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.

Rosana de Cássia de Souza Schneider

2013-03-01

283

Mapping small-scale vegetation changes in Mexico  

Science.gov (United States)

This research attempts to map small-scale vegetation changes in Mexico. Forty-eight weeks of coarse resolution Advanced Very High Resolution Radiometer Normalized Difference Vegetation Index (NDVI), a digitized climax vegetation map, land cover samples from space shuttle photographs and actual vegetation samples were used as inputs. Principal components analyses and a clustering algorithm were applied to the NDVI data to generate a single layer that was stratified by the climax vegetation zones map. The purpose is to create a new layer that differentiates climax vegetation (hypothesized potential vegetation) from non-climax vegetation land covers. One of the keys to developing a present-day vegetation map was differentiating intrazone land covers based on the stratification; as great as 75% of the sampled land cover types differed from the climax vegetation. The present-day vegetation map achieved 80% classification accuracy when calculated from available ground reference data. About 55% of the temperate zones and 37% of the tropical zones were found to contain original climax vegetation. Most changes coincide with areas of major agricultural activity.

Turcotte, Kevin M.; Lulla, Kemlesh; Venugopal, Gopalan

1993-01-01

284

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  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 compatibi...

Hirokazu Yamamoto; Tomoaki Miura; Satoshi Tsuchida

2012-01-01

285

Monitoring Vegetation Phenological Cycles in Two Different Semi-Arid Environmental Settings Using a Ground-Based NDVI System: A Potential Approach to Improve Satellite Data Interpretation  

Directory of Open Access Journals (Sweden)

Full Text Available In semi-arid environmental settings with sparse canopy covers, obtaining remotely sensed information on soil and vegetative growth characteristics at finer spatial and temporal scales than most satellite platforms is crucial for validating and interpreting satellite data sets. In this study, we used a ground-based NDVI system to provide continuous time series analysis of individual shrub species and soil surface characteristics in two different semi-arid environmental settings located in the Great Basin (NV, USA. The NDVI system was a dual channel SKR-1800 radiometer that simultaneously measured incident solar radiation and upward reflectance in two broadband red and near-infrared channels comparable to Landsat-5 TM band 3 and band 4, respectively. The two study sites identified as Spring Valley 1 site (SV1 and Snake Valley 1 site (SNK1 were chosen for having different species composition, soil texture and percent canopy cover. NDVI time-series of greasewood (Sarcobatus vermiculatus from the SV1 site allowed for clear distinction between the main phenological stages of the entire growing season during the period from January to November, 2007. NDVI time series values were significantly different between sagebrush (Artemisia tridentata and rabbitbrush (Chrysothamnus viscidiflorus at SV1 as well as between the two bare soil types at the two sites. Greasewood NDVI from the SNK1 site produced significant correlations with chlorophyll index (r = 0.97, leaf area index (r = 0.98 and leaf xylem water potential (r = 0.93. Whereas greasewood NDVI from the SV1 site produced lower correlations (r = 0.89, r = 0.73, or non significant correlations (r = 0.32 with the same parameters, respectively. Total percent cover was estimated at 17.5% for SV1 and at 63% for SNK1. Results from this study indicated the potential capabilities of using this ground-based NDVI system to extract spatial and temporal details of soil and vegetation optical properties not possible with satellite derived NDVI.

Malika Baghzouz

2010-04-01

286

Kinetics of soil enzyme activities under different ecosystems: An index of soil quality  

Scientific Electronic Library Online (English)

Full Text Available SciELO Chile | Language: English Abstract in english 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

Monty, Kujur; Amiya, Kumar Patel.

287

Feed intake and activity level of two broiler genotypes foraging different types of vegetation in the finishing period  

DEFF Research Database (Denmark)

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 Ã? 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. 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 use of the range area, activity level, and feed content in the crops were observed in relation to genotype, sex, age of broilers, and also the time of day. Foraging activity was positively correlated with age. Medium-growth broilers spent more time inside and closer to the broiler houses during the 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 medium-growing genotype had an intake of 9 g for females and 20 g for males. In conclusion, limitation of supplemented protein feed in the finishing period may be acceptable for broilers that have access to highly nutritious vegetation.

Almeida, Gustavo Fonseca; Hinrichsen, Lena Karina

2012-01-01

288

Carbon mineralization of flooded boreal soil and vegetation under different temperature and oxygen conditions  

Science.gov (United States)

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.

Kim, Y.; Ullah, S.; Roulet, N.; Moore, T.

2009-05-01

289

Effect of Different Levels of NaCl and KCl on Growth and Some Biological Indexes of Wheat Plant  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this study, it was aimed to determine the effects of different levels (0, 15, 30 and 60 mM) of NaCl and KCl salt on seedling growth and some biological indexes of wheat. Shoot height, stem diameter, leaves number of plant, fresh weight of shoot and dry matter weight index were investigated. The results showed that biological index of wheat decreased with increasing salt in comparison to control. The adverse affect of NaCl on wheat plant was obtained higher than that of KCl. This should car...

2007-01-01

290

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)

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.

Márcia Aparecida Andreazzi

2006-07-01

291

Effect of Different Vegetable Oils (Red Palm Olein, Palm Olein, Corn Oil and Coconut Oil on Lipid Profile in Rat  

Directory of Open Access Journals (Sweden)

Full Text Available The objective of the study was to evaluate the effects of different vegetable oils [red palm olein (RPO, palm olein (PO, corn oil (CO and coconut oil (COC] on lipid profile in rat. Sixty six Sprague Dawley male rats were randomly divided into eleven groups of 6 rats per group and were treated with 15% concentrations of RPO, PO, CO and COC for 4 and 8 weeks. Rats in control group were given normal rat pellet only while in treated groups 15% of additional vegetable oils were given. The results at 4 weeks showed a decline in Low Density Lipoprotein Cholesterol (LDL-C values at RPO and PO groups whereas in CO and COC groups the LDL-C were increased compared to the control group. The High Density Lipoprotein Cholesterol (HDL-C values increased in RPO and PO groups whereas it was declined in CO and COC groups compared to the control group. At 8 weeks, there was no significant difference (P ? 0.05 in HDL-C of rats treated with vegetable oils compared to the control group. However, the LDL-C in RPO and PO was significantly decreased (P ? 0.05 in the LDL-C and there was no significant difference (P?0.05 for CO and COC groups compared to the control groups. The mean value of the LDL-C after 8 weeks in the control group, RPO, PO, CO, and COC groups were 66.1 mg/dl, 31.9 mg/dl, 41.1 mg/dl, 50.41 mg/dl and 54.31 mg/dl respectively. There was significant decreased (P ? 0.05 in the total cholesterol (TC in RPO group for 4 weeks compared to the control group while the TC in PO, CO and COC were within the normal range. The results of TC in all treated rats for 8 weeks were within the normal range. There was no significant difference in TC of rats treated with vegetable oils compared to the control group. Triglycerides (TG in all treated rats for 4 weeks were within the normal range whereas the TG in RPO, PO and CO groups for 8 weeks were significant increase (P ? 0.05 compared to the control group but there was no significant difference between the control group and COC group.

Aminah Abdullah

2011-06-01

292

Vegetative Growth of the Green Alga Haematococcus pluvialis Cultivated in Different Light-Path Lengths  

Directory of Open Access Journals (Sweden)

Full Text Available The growth of the green alga Haematococcus pluvialis in vegetative stage is one of the most important parts in the whole cultivation process. The aim of the study was to show the growth characteristics of the alga under 100 and 170 ?mol photon m-2 s-1 light intensities in the longer Light Path (LP lengths (17.5, 23.0 and 27.5 cm than the ones usually used. Maximum cell numbers increased from 15.7, 11.5 and 10.1 x 104 cells mL-1 in 100 ?mol light to 17.9, 12.9 and 11.1 x 104 cells mL-1 under 170 ?mol light for 17.5, 23.0 and 27.5 cm LP lengths, respectively. The cell concentration per liter volume increased as in the pattern of cell count. The Chl/Car ratio in the whole groups, a very useful indicator to evaluate the stress on the cells, increased by the shift of light from 100 to 170 ?mol. The close correlation between cell number and absorbance value at 680 nm (p<0.04 showed the biomass concentration to depend on the cell count rather than DW and cell diameter. In addition, cell diameter did not change during the experiments. As a result of the findings, the use of longer LP lengths may be an alternative method in the vegetative cultivation of the light sensitive alga Haematococcus pluvialis by the higher light intensities than 200 ?mol photon m-2 s-1 using mutual shading effect.

Tolga Goksan

2006-01-01

293

Method for characterising vegetation  

Digital Repository Infrastructure Vision for European Research (DRIVER)

[EN] The invention relates to a method that can be used to determine situations of water stress in vegetation. The method is based on radiative transfer models formed from thermal and multi-spectrum images, which are subsequently inverted to obtain a theoretical photochemical reflectance index (PRI) which can be used to determine the situation of the vegetation by means of a PRI comparison.

Jime?nez Berni, Jose? A.; Fereres Castiel, Eli?as; Sua?rez Barranco, Mari?a Dolores; Zarco-tejada, Pablo J.

2010-01-01

294

Stability of potato chip fried in vegetable oils with different degree of unsaturation. Effect of ascorbyl palmitate during storage  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Four vegetable oils with different polyunsaturated/saturated fatty acid ratio (P/S): 5.2 for sunflower oil, 3.,4 for canola rapeseed oil, 0.4 for a blend of palm oleic and canola rapeseed oil (80:20), and 0.3 for palm olein were assayed for stability of crisps fried in these oils during storage at 60º C. The action of ascorbyl palmitate with special attention to its synergistic effect on the natural antioxidants was also tested. by addition to the fried potatoes. The evolution of ...

Masson, L.; Robert, P.; Dobarganes, M. C.; Urra, C.; Romero, N.; Ortiz, J.; Goicoechea, E.; P Rez, P.; Salam, M.; Torres, R.

2002-01-01

295

Biogenic NO emission from a spruce forest soil in the Fichtelgebirge (Germany) under the influence of different understorey vegetation cover  

Science.gov (United States)

Within the framework of the EGER project (ExchanGE processes in mountainous Regions) soil samples have been taken from the spruce forest site "Weidenbrunnen" (Fichtelgebirge, Germany) in September 2008 to determine the NO exchange in the laboratory and for a series of soil analyses. The soil was sampled below different understorey vegetation covers: young Norway spruce, moss/litter, blueberries and grass. We investigated the net NO release rate from corresponding organic layers as well as from the A horizon of respective soils. Additionally we measured pH, C/N ratio, contents of ammonium, nitrate, and organic C, bulk density, the thickness of the organic layer and the quality of the organic matter. Net NO release rates (as well as the NO production and NO consumption rates) from the soil samples were determined by a fully automated laboratory incubation & fumigation system. Purified dry air passed five dynamic incubation chambers, four containing water saturated soil samples and one reference chamber. By this procedure, the soil samples dried out slowly (within 2-6 days), covering the full range of soil moisture (0-300% gravimetric soil moisture). To quantify NO production and NO consumption rates separately, soil samples were fumigated with zero-air (approx. 0 ppb NO) and air of 133 ppb NO. The chambers were placed in a thermostatted cabinet for incubation at 10 an 20Ë? C. NO and H2O concentrations at the outlet of the five dynamic chambers were measured sequentially by chemiluminescence and IR-absorption based analyzers, switching corresponding valves every two minutes. Net NO release rates were determined from the NO concentration difference between soil containing and reference chambers. Corresponding measurements of H2O mixing ratio yielded the evaporation loss of the soil samples, which (referenced to the gravimetric soil water content before and after the incubation experiment) provided the individual soil moisture contents of each soil samples during the incubation experiment. Our contribution focus net NO release rates, NO production and NO consumption rates of spruce forest soils sampled under different understorey vegetation covers. Generally, organic layers show significant higher NO production and NO consumption rates than the soils from the corresponding A horizons. Soils under the understorey vegetation cover "moos/litter" revealed the lowest NO production and NO consumption rates. Net NO release rates, NO production and NO consumption rates of soil samples obtained below the four different under- storey vegetation covers will be discussed in terms of pH, C/N ratio, contents of ammonium, nitrate, and organic C, bulk density, thickness of organic layer, as well as quality of the organic matter.

Bargsten, A.; Andreae, M. O.; Meixner, F. X.

2009-04-01

296

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)

2007-10-01

297

Estimates of leaf area index from spectral reflectance of wheat under different cultural practices and solar angle  

Science.gov (United States)

The influence of management practices and solar illumination angle on the leaf area index (LAI) was estimated from measurements of wheat canopy reflectance evaluated by two methods, a regression formula and an indirect technique. The date of planting and the time of irrigation in relation to the stage of plant growth were found to have significant effects on the development of leaves in spring wheat. A reduction in soil moisture adversely affected both the duration and magnitude of the maximum LAI for late planting dates. In general, water stress during vegetative stages resulted in a reduction in maximum LAI, while water stress during the reproductive period shortened the duration of green LAI in spring wheat. Canopy geometry and solar angle also affected the spectral properties of the canopies, and hence the estimated LAI. Increase in solar zenith angles resulted in a general increase in estimated LAI obtained from both methods.

Asrar, G.; Kanemasu, E. T.; Yoshida, M.

1985-01-01

298

Land Surface Temperature Retrieval by Using ATCOR3_T and Normalized Difference Vegetation Index Methods in Penang Island  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Problem statement: Many studies have been devoted to establish the methodology for retrieval of LST from single channel algorithm by utilizing Landsat satellite images. However, this method required many atmospheric parameters to retrieve LST. Thus, it is very difficult to acquire the complete information for atmospheric parameters. Approach: While for ATCOR3_T, this method can be used to retrieve LST without any historical atmospheric parameters like transmittance and mean-atmo...

Tan, K. C.; Lim, H. S.; Matjafri, M. Z.; Abdullah, K.

2010-01-01

299

Land Surface Temperature Retrieval by Using ATCOR3_T and Normalized Difference Vegetation Index Methods in Penang Island  

Directory of Open Access Journals (Sweden)

Full Text Available Problem statement: Many studies have been devoted to establish the methodology for retrieval of LST from single channel algorithm by utilizing Landsat satellite images. However, this method required many atmospheric parameters to retrieve LST. Thus, it is very difficult to acquire the complete information for atmospheric parameters. Approach: While for ATCOR3_T, this method can be used to retrieve LST without any historical atmospheric parameters like transmittance and mean-atmospheric temperature. In this study, the retrieval of LST value from ATCOR3_T method was compared with the NDVI method, in order to calculate the average percentage of error. Results: The obtained result showed that the LST value retrieved from ATCOR3_T can be used to generate the LST map in equatorial region, such as Penang Island. The average percentage of error for 40 points of LST gives the percentage of 5.13%. Conclusion/Recommendations: Both of these methods can be used to estimate LST value in the study area. In addition, the retrieval of LST value from multi-temporal satellite images is useful to study urban heat island effects in Penang Island for future study.

K. C. Tan

2010-01-01

300

Use of Normalized Difference Vegetation Index (NDVI) Habitat Models to Predict Breeding Birds on the San Pedro River, Arizona.  

Science.gov (United States)

Successful management practices of avian populations depend on understanding relationships between birds and their habitat, especially in rare habitats, such as riparian areas of the desert Southwest. Remote-sensing technology has become popular in habita...

C. Ripper T. M. McFarland

2013-01-01

 
 
 
 
301

Toxicity of Trace Elements in Different Vegetables Grown on Potentially Contaminated Sites of the Korangi Industrial Area, Karachi Pakistan  

Directory of Open Access Journals (Sweden)

Full Text Available This study presents toxicity of trace elements (Zn, Cu, Fe, Mn, Cd, Cr, Ni, Pb in different vegetables grown on potentially contaminated sites of the Korangi Industrial Area, Karachi (Sindh Pakistan. A total of 40 effluent irrigated and 4 tubewell irrigated considered as background samples were collected and analyzed for trace elements concentration. The maximum concentrations of trace elements absorbed by different vegetables grown on effluent irrigated soils were 78.8, 103.25, 638.8, 973.3, 7.4, 22.5, 88.0 and 64.0 mg kg-1 for Zn, Cu, Fe, Mn, Cd, Cr, Ni and Pb, respectively. However, the background plant samples showed the maximum concentrations of 32.4, 19.5, 172.5, 111.8, 1.8, 4.2, 14.8 and 12.4 mg kg-1 for the above respective elements. The values observed in this study were also compared with the toxic and excessive levels. The comparison showed that 100, 13, 18, 50, 93 and 50% of samples contained toxic or excessive levels of Cu, Mn, Cd, Cr, Ni and Pb, respectively. The concentration of trace elements in effluents irrigated plants were higher than those in tubewell irrigated plants and also higher than those generally reported in the literature.

Midrar-ul-Haq

2005-01-01

302

The hydrological responses of different land cover types in a re-vegetation catchment area of the Loess Plateau, China  

Directory of Open Access Journals (Sweden)

Full Text Available The impact of re-vegetation on soil moisture dynamics was investigated by comparing five land cover types. Soil moisture and temperature variations under grass (Andropogon, subshrub (Artemisia scoparia, shrub (Spiraea pubescens, tree (Robinia pseudoacacia, and crop (Zea mays vegetation were monitored in an experiment performed during the growing season of 2011. There were more than 10 soil moisture pulses during the period of data collection, and the surface soil moisture of all of the land cover types showed an increasing trend. Corn cover was associated with consistently higher soil moisture readings than the other surfaces. Grass and subshrubs showed an intermediate moisture level, with that of grass being slightly higher than that of subshrub most of the time. Shrubs and trees were characterized by lower soil moisture readings, with the shrub levels consistently being slightly higher than those of the trees. With the exception of the corn land cover type, the average soil temperature showed the same regime as the average moisture content, but exhibiting a downward trend throughout the observation period. Three typical decreasing periods were chosen to compare the differences in water losses. In periods of both relatively lower and higher water soil moisture contents, subshrubs lost the largest amount of water. The daily water loss associated with corn was most variable. The tree and shrub sites presented an intermediate level, with that of tree being slightly higher compared to shrub; the daily water loss trends of these two land cover types were similar and were more stable than those of the other types. The amount of water loss related to the grass land cover type is determined by the initial moisture content. Soil under subshrubs acquired and retained soil moisture resources more efficiently than the other cover types, representing an adaptive vegetation type in this area.

S. Wang

2012-05-01

303

The hydrological responses of different land cover types in a re-vegetation catchment area of the Loess Plateau, China  

Science.gov (United States)

The impact of re-vegetation on soil moisture dynamics was investigated by comparing five land cover types. Soil moisture and temperature variations under grass (Andropogon), subshrub (Artemisia scoparia), shrub (Spiraea pubescens), tree (Robinia pseudoacacia), and crop (Zea mays) vegetation were monitored in an experiment performed during the growing season of 2011. There were more than 10 soil moisture pulses during the period of data collection, and the surface soil moisture of all of the land cover types showed an increasing trend. Corn cover was associated with consistently higher soil moisture readings than the other surfaces. Grass and subshrubs showed an intermediate moisture level, with that of grass being slightly higher than that of subshrub most of the time. Shrubs and trees were characterized by lower soil moisture readings, with the shrub levels consistently being slightly higher than those of the trees. With the exception of the corn land cover type, the average soil temperature showed the same regime as the average moisture content, but exhibiting a downward trend throughout the observation period. Three typical decreasing periods were chosen to compare the differences in water losses. In periods of both relatively lower and higher water soil moisture contents, subshrubs lost the largest amount of water. The daily water loss associated with corn was most variable. The tree and shrub sites presented an intermediate level, with that of tree being slightly higher compared to shrub; the daily water loss trends of these two land cover types were similar and were more stable than those of the other types. The amount of water loss related to the grass land cover type is determined by the initial moisture content. Soil under subshrubs acquired and retained soil moisture resources more efficiently than the other cover types, representing an adaptive vegetation type in this area.

Wang, S.; Fu, B. J.; Gao, G. Y.; Zhou, J.

2012-05-01

304

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)

1997-01-01

305

Animal and vegetal pole cells of early Xenopus embryos respond differently to maternal dorsal determinants: implications for the patterning of the organiser  

Energy Technology Data Exchange (ETDEWEB)

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/{beta}-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/{beta}-catenin/Siamois pathway. (author).

Darras, Sebastien; Lemaire, Patrick [CNRS-Universite de la Mediterranee, Lab. de Genetique et Physiologie du Developpement, Marseille, 13 (France); Marikawa, Yusuke; Elinson, R.P. [Toronto Univ., Zoology Dept., Toronto, ON (Canada)

1997-12-31

306

Effects of vegetation structure on biomass accumulation in a coupled water-carbon-energy balance model in West Africa  

Science.gov (United States)

A myriad of interactions exist between vegetation and local climate for arid and semi-arid regions. Vegetation function, structure and individual behavior have enormous 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 on equilibrium biomass states. Two different strategies of vegetation adaptation to water stress are included. 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. Under dry conditions vegetation tries to maximize the Water Use Efficiency and Leaf Area Index as it tries to maximize carbon gain. However, as the vegetation can also engineer its environment by extracting water from the surrounding bare soil (thereby forming patches of vertical vegetation) it can also minimize its vegetation cover. With increasing precipitation, the 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' regime to a 'growing' regime. The new modeling framework is useful to represent the effects of dynamic vegetation structure in coupled land-atmosphere feedback models.

Yin, Zun; Dekker, Stefan; van den Hurk, Bart; Dijkstra, Henk

2013-04-01

307

Phytomass mapping of the "seridó caatinga" vegetation by the plant area and the normalized difference vegetation indeces Mapeamento da fitomassa da caatinga do seridó pelos índices de área de planta e de vegetação da diferença normalizada  

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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.A fitomassa, principalmente arbórea, é informação necessária em atividades econômicas e ambientais, como políticas de uso do recurso madeireiro, manejo florestal, estudos de ciclagem de nutrientes, absorção de CO2, entre outros. A finalidade deste estudo foi a verificação de um método empírico para o mapeamento da fitomassa da Caatinga do Seridó, integrando-se um inventário de fitomassa, o índice de área de planta (IAP e o índice de vegetação da diferença normalizada (NDVI, por meio de imagens Landsat TM. Na primeira etapa foram desenvolvidos e testados modelos lineares, logarítmicos e não lineares. A abordagem de tamanho foi arbustiva e arbórea, incluindo-se a maior parte dos indivíduos que contribuem na resposta espectral mensurada por imagens de satélite. Em uma segunda etapa utilizamos o parâmetro orbital, NDVI, para o mapeamento do IAP, que por sua vez, foi utilizado para mapear a fitomassa. Os desvios entre mensurações de IAP e estimativas a partir do NDVI, variaram de 0 a 84%, enquanto que os desvios entre Peso Seco Total de Fitomassa por ha obtidos pelo mapeamento e por equações dendrométricas, variaram de 5 a 104%, com grandes tendências de 166 e 448% para áreas de caatinga aberta, provocada pela contribuição do estrato herbáceo no NDVI.

Thomaz Corrêa e Castro da Costa

2002-12-01

308

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)

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.)

Grabe, F.

2002-01-01

309

Experimenting with 3 different input-output mapping structures of ANN models for predicting CSI 300 index  

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Full Text Available Forecasting the stock market price index is a challenging task. Many scholars have tried on many kinds of models to predict the stock index, mainly autoregressive integrated moving average model (ARIMA, artificial neural networks (ANN with genetic algorithms (GA. This paper documents a set of thorough empirical tests of ANN's with different choices of inputs and different numbers of hidden neurons for forecasting the CSI 300 - the benchmark stock index of China. The prediction accuracy is measured in terms of hit rate and mean square error. The trend of the hit rate is observed by adjusting the window length and the number of hidden neurons. The results show that the hit rate is highest when the window length is between 14 days to 20 days.

Chengzhao ZHANG

2014-03-01

310

The Effect of Pre-Exercise Carbohydrate Feeding with Different Glycemic Index on Endurance Exercise Capacity  

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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 w...

2004-01-01

311

The Influence of Different Vegetable Oils on Some ?-3 Polyunsaturated Fatty Acids from Thigh and Abdominal Fat of Broilers  

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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.

Drago? Sorin Fota

2011-05-01

312

CROP YIELD OF CONILON COFFEE PLANTS OF DIFFERENT LEVELS OF VEGETATIVE VIGOR AND RUST SEVERITY  

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Full Text Available Os programas de melhoramento genético têm buscado disponibilizar cultivares resistentes à ferrugem, visto que o controle genético constitui o método mais econômico e eficiente no manejo dessa doença. Este trabalho objetivou estudar a relação entre a severidade da ferrugem, o vigor vegetativo e a capacidade produtiva de plantas de café conilon. O experimento foi realizado na Fazenda Experimental de Bananal do Norte (INCAPER, localizada em Cachoeiro de Itapemirim, no sul do Estado do Espírito Santo. Foram avaliadas as produtividades de 20 combinações entre 4 níveis de vigor vegetativo e 5 níveis de severidade da ferrugem. O delineamento experimental utilizado foi em blocos casualizados com 4 repetições e 5 plantas por parcela experimental. Verificou-se a formação de cinco grupos de médias homogêneas para as combinações e ajustou-se as médias a um modelo de superfície de resposta. As combinações entre os níveis de vigor vegetativo e severidade da ferrugem influenciaram a produtividade do cafeeiro conilon nas condições avaliadas. O fator vigor vegetativo foi mais limitante que o fator severidade da ferrugem na determinação da produtividade de plantas de café conilon.The breeding programs have sought to provide rust-resistant cultivars, since the genetic control is the most economical and efficient method of management of this plant disease. This study investigated the relationship between the rust severity, vigor and crop yield capacity of conilon coffee plants. The experiment was conducted in the Experimental Farm of Bananal do Norte (INCAPER, located in Cachoeito de Itapemirim, in the southern state of Espírito Santo. The crop yield was evaluated in 20 combinations of 4 levels of vigor and 5 levels of rust severity. The experimental design used was in randomized blocks, with four replications and 5 plants per plot. There was the formation of five groups of homogeneous means for the combinations and the means was adjusted to a response surface model. The combinations between the levels of vigor and rust severity influenced the crop yield of conilon coffee in the evaluated conditions. The vegetative vigor factor was the more limiting than the rust severity in determining the coffee plants yield.

Wagner Nunes Rodrigues

2012-12-01

313

Mapping agroecological zones and time lag in vegetation growth by means of Fourier analysis of time series of NDVI images  

Science.gov (United States)

Examples are presented of applications of a fast Fourier transform algorithm to analyze time series of images of Normalized Difference Vegetation Index values. The results obtained for a case study on Zambia indicated that differences in vegetation development among map units of an existing agroclimatic map were not significant, while reliable differences were observed among the map units obtained using the Fourier analysis.

Menenti, M.; Azzali, S.; Verhoef, W.; Van Swol, R.

1993-01-01

314

Regional Differences as Barriers to Body Mass Index Screening Described by Ohio School Nurses  

Science.gov (United States)

Background: Body mass index (BMI) screening is advocated by the National Association of School Nurses (NASN). Research identifying barriers to BMI screening in public elementary school settings has been sparse. The purpose of the study was to identify barriers and facilitating factors of BMI screening practices among Ohio school nurses working in…

Stalter, Ann M.; Chaudry, Rosemary V.; Polivka, Barbara J.

2011-01-01

315

Response of vegetation to the 2003 European drought was mitigated by height  

Science.gov (United States)

The effects on climate of land-cover change, predominantly from the conversion of forests to crops or grassland, are reasonably well understood for low and high latitudes but are largely unknown for temperate latitudes. The main reason for this gap in our knowledge is that there are compensating effects on the energy and water balance that are related to changes in land-surface albedo, soil evaporation and plant transpiration. We analyse how vegetation height affected the response of vegetation during the 2003 European drought using precipitation data, temperature data, normalized difference vegetation index data and a new vegetation height data set obtained from the Geoscience Laser Altimeter System (GLAS) on the Ice, Cloud and land Elevation Satellite (ICESat). At the height of the 2003 drought we find for tall vegetation a significantly smaller decrease in vegetation index and a smaller diurnal temperature (DTR) range, indicating less water stress and drought impacts on tall vegetation. Over Germany for example, 98% of significant correlations showed a smaller anomaly in vegetation index anomaly with greater height, and 95% of significant correlations showed a smaller DTR with greater vegetation height. Over France the equivalent percentages were 94 and 88%, respectively. Vegetation height is likely associated with greater rooting depth, canopy heat capacity or both. Our results suggest that land-surface models can be improved by better estimates of vegetation height and associated with this a more realistic response to drought.

Bevan, S. L.; Los, S. O.; North, P. R. J.

2014-06-01

316

Glycaemic index of different coconut (Cocos nucifera)-flour products in normal and diabetic subjects.  

Science.gov (United States)

The glycaemic index (GI) of commonly consumed bakery products supplemented with increasing levels of coconut (Cocos nucifera) flour was determined in ten normal and ten diabetic subjects. Using a randomized crossover design, the control and test foods were fed in random order on separate occasions after an overnight fast. Blood samples were collected through finger prick before and after feeding and were analysed for glucose levels using a clinical chemistry analyser. The significantly low-GI (<60) foods investigated were: macaroons (GI 45.7 (sem 3.0)) and carrot cake (GI 51.8 (sem 3.3)), with 200-250 g coconut flour/kg (P<0.05). The test foods with 150 g coconut flour/kg had GI ranging from 61.3 to 71.4. Among the test foods, pan de sal (GI 87.2 (sem 5.5)) and multigrain loaf (GI 85.2 (sem 6.8)) gave significantly higher GI with 50 and 100 g coconut flour/kg respectively (P<0.05). On the other hand, granola bar and cinnamon bread with 50 and 100 g coconut flour/kg respectively gave a GI ranging from 62.7 to 71.6 and did not differ significantly from the test foods with 150 g coconut flour/kg (P<0.05). A very strong negative correlation (r -0.85, n 11, P<0.005) was observed between the GI and dietary fibre content of the test foods supplemented with coconut flour. In conclusion, the GI of coconut flour-supplemented foods decreased with increasing levels of coconut flour and this may be due to its high dietary fibre content. The results of the present study may form a scientific basis for the development of coconut flour as a functional food. However, the fat content of coconut flour-supplemented food should always be considered to optimize the functionality of coconut fibre in the proper control and management of diabetes mellitus. PMID:13129460

Trinidad, Trinidad P; Valdez, Divinagracia H; Loyola, Anacleta S; Mallillin, Aida C; Askali, Faridah C; Castillo, Joan C; Masa, Dina B

2003-09-01

317

Assessment of soil biological quality index (QBS-ar) in different crop rotation systems in paddy soils  

Science.gov (United States)

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

Nadimi-Goki, Mandana; Bini, Claudio; haefele, Stephan

2013-04-01

318

Determination of surface tension, optical rotativity and refractive index of polymer polyvinyl alcohol PVA, in various solvents at different concentrations  

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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.

Sarojini Panda

2011-12-01

319

Climate Change Implications to Vegetation Production in Alaska  

Science.gov (United States)

Investigation of long-term meteorological satellite data revealed statistically significant vegetation response to climate drivers of temperature, precipitation and solar radiation with exclusion of fire disturbance in Alaska. Abiotic trends were correlated to satellite remote sensing observations of normalized difference vegetation index to understand biophysical processes that could impact ecosystem carbon storage. Warming resulted in disparate trajectories for vegetation growth due to precipitation and photosynthetically active radiation variation. Interior spruce forest low lands in late summer through winter had precipitation deficit which resulted in extensive fire disturbance and browning of undisturbed vegetation with reduced post-fire recovery while Northern slope moist alpine tundra had increased production due to warmer-wetter conditions during the late 1990s and early 2000s. Coupled investigation of Alaska s vegetation response to warming climate found spatially dynamic abiotic processes with vegetation browning not a result from increased fire disturbance.

Neigh, Christopher S.R.

2008-01-01

320

Flow characteristics in different densities of submerged flexible vegetation from an open-channel flume study of artificial plants  

Science.gov (United States)

The effect of submerged flexible vegetation on flow structure (e.g. flow velocity, Reynolds shear stress, turbulence intensity and Manning coefficient) was experimentally studied with a 3D Acoustic Doppler Velocimeter (ADV) in an open-channel flume. The results from flow observations over artificial plants (designed to simulate natural vegetation) showed that flow structure was affected markedly by the presence of submerged flexible vegetation. The study provides understanding of flow patterns, variation in velocity profile and turbulence structures that are affected by plant stem density. The study also reveals how the flow patterns return to stability at the downstream end of the vegetated area which is critical in determining the length of the vegetated areas for restoration cases. Also, new mathematical expressions (equations) have been formulated to clearly express variations in velocity profile, Manning coefficient and flow discharge ratio with vegetation density. Vertically, the velocity profile could be roughly divided into three layers, including the upper non-vegetated layer, the middle canopy layer, and the lower sheath layer. In the upper non-vegetated layer, velocity profiles followed the logarithmic law, and a corresponding empirical equation was developed based on the observed data. The flow is from left to right in this study, and the velocity profile followed a left round bracket "(" with the minimum point located at the canopy area (0.7Hv, where Hv denotes vegetation height) within the middle canopy layer. However, the velocity profile followed a right round bracket ")" in the lower sheath section layer with the maximum point located at the sheath section (0.2Hv). With increasing vegetation density, the velocity and corresponding flow rate increased in the upper non-vegetated layer and decreased within the middle canopy layer and the lower sheath layer. The ratio of average flow discharge in the non-vegetated and vegetated layers followed the exponential function law with increasing vegetation density. This analysis revealed the effect of vegetation on flood potential and flow bottom scour. Reynolds stresses peaked above the canopy top (z/Hv = 1.0-1.2, here z denotes vertical coordinate), and the turbulence intensities reached their maximum peak at two locations including the sheath section (z/Hv = 0.1-0.4) and the canopy top (z/Hv = 1.0-1.6) for all vegetation densities. Manning coefficient was highly correlated to vegetation density and inflow rate with new empirical equations being proposed.

Li, Yiping; Wang, Ying; Anim, Desmond Ofosu; Tang, Chunyan; Du, Wei; Ni, Lixiao; Yu, Zhongbo; Acharya, Kumud

2014-01-01

 
 
 
 
321

Vegetative development of orchid hybrid in different substratesDesenvolvimento vegetativo de híbrido de orquídea em diferentes substratos  

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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’.

Alessandro Garrett Dronk

2012-12-01

322

Chemistry of soil solutions under different kinds of vegetation in the vicinity of a thermal power station  

Energy Technology Data Exchange (ETDEWEB)

The paper discusses the influence of atmospheric deposition on the chemical characteristics of soil solutions in a small catchment area in NW Spain. The soils, were sampled from seven sites supporting different forms of vegetation (deciduous and pine forest and heath). Soil solutions were extracted, by the column displacement method, from soil samples collected monthly from March 1992 until November 1993. The most common ions in all horizons were Cl{sup -} and Na{sup +} due to marine influence. In the surface horizons (0-10 cm), relatively high concentrations of SO{sub 4}{sup 2-} (150-380 {mu}mol) and Zn (similar to 2 {mu} mol) were obtained, with good correlation between the two ions. These results, along with the prevalence of inorganic forms of Al(50-90% of total Al), were related to the effects of acidic deposition in the catchment area.

Fernandez Sanjurjo, M.J.; Alvarez, E.; Vega, V.F.; Garcia Rodeja, E. [Universidad de Santiago de Compostela, Santiago de Compostela (Spain). Dept. de Edafologia y Quimica Agricola

1998-12-01

323

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  

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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.

Satoshi Tsuchida

2012-08-01

324

Automatic Assessment of Global Craniofacial Differences between Crouzon mice and Wild-type mice in terms of the Cephalic Index  

DEFF Research Database (Denmark)

This paper presents the automatic assessment of differences between Wild-Type mice and Crouzon mice based on high-resolution 3D Micro CT data. One factor used for the diagnosis of Crouzon syndrome in humans is the cephalic index, which is the skull width/length ratio. This index has traditionally been computed by time-consuming manual measurements that prevent large-scale populational studies. In this study, an automatic method to estimate cephalic index for this mouse model of Crouzon syndrome is presented. The method is based on constructing a craniofacial atlas of Wild-type mice and then registering each mouse to the atlas using affine transformations. The skull length and width are then measured on the atlas and propagated to all subjects to obtain automatic measurements of the cephalic index. The registration accuracy was estimated by RMS landmark errors. Even though the accuracy of landmark matching is limited using only affine transformations, the errors were considered acceptable. The automatic estimation of the cephalic index was in full agreement with the gold standard measurements. Discriminant analysis of the three scaling parameters resulted in a good classification of the mouse groups.

�lafsdóttir, Hildur; Darvann, Tron Andre

2006-01-01

325

GPS phase difference variation statistics: A comparison between phase scintillation index and proxy indices  

Science.gov (United States)

Scintillated GPS phase observations are traditionally characterized by the phase scintillation index, derived from specialized GPS receivers usually tracking at 50 Hz. Geodetic quality GPS receivers, on the other hand, are normally tracking at frequencies up to 1 Hz. However, availability of continuously operating geodetic receivers both in time and geographical location are superior to scintillation receiver's coverage in many parts of the world. This motivates scintillation studies using regional and global geodetic GPS networks. Previous studies have shown the usefulness of GPS estimated total electron content variations for detecting ionospheric irregularities. In this paper, collocated geodetic and scintillation receivers are employed to compare proxy indices derived from geodetic receivers with the phase scintillation index during quiet and moderately disturbed ionospheric conditions. Sensitivity of the phase scintillation indices at high latitude stations to geomagnetic activity is discussed. Global mapping of ionospheric disturbances using proxy indices from real-time 1 Hz GPS stations are also presented.

Ghoddousi-Fard, Reza; Prikryl, Paul; Lahaye, François

2013-10-01

326

Transmission of Light in Crystals with different homogeneity: Using Shannon Index in Photonic Media  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 statist...

Bellingeri, Michele; Longhi, Stefano; Scotognella, Francesco

2010-01-01

327

Differences in Dietary Patterns among College Students According to Body Mass Index  

Science.gov (United States)

Objective and Participants: The authors surveyed 557 undergraduate students aged 18-56 years to assess weight status, health behaviors, and dietary variety. Methods: They used body mass index (BMI) to divide students into 4 weight categories: underweight (BMI less than 19 kg/m2), healthy weight (19 kg/m2 to 24.99 kg/m2), overweight (25 kg/m2 to…

Brunt, Ardith; Rhee, Yeong; Zhong, Li

2008-01-01

328

Temporal variation of aqueous-extractable Ca, Mg and K in acidified forest mountainous soils under different vegetation cover  

Science.gov (United States)

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.

Tejnecky, V.; Bradová, M.; Boruvka, L.; Vasat, R.; Nemecek, K.; Ash, C.; Sebek, O.; Rejzek, J.; Drabek, O.

2012-12-01

329

The Regularities of Mutagenic Action of gamma-Radiation on Vegetative Bacillus subtilis Cells with Different Repair Genotype  

CERN Document Server

The regularities of induction of his^-\\to his^+ mutations in vegetative Bacillus subtilis cells with different repair capacity after gamma-irradiation have been studied. The wild type cells, polA1, recE4, recA, recP, add5, recH were used in experiments. It was shown that radiation-induced mutagenesis is determined by a repair genotype of cells. The blocking of different reparation genes is reflected on mutagenesis ratio by the various ways. A frequency of induction mutations in polA strain is higher than in wild type cells and it is characterized by the linearly-quadratic dose curve. The different rec^- strains that belong to various epistatic groups reveal an unequal mutation induction. The add5 and recP strains are characterized by the high-level induction mutations in contrast with the wild type cells. The mutagenesis in recE and recH strains, on the contrary, sharply reduces. The different influence of rec genes inhering to various epistatic groups on mutagenesis in Bacillus subtilis cells probably reflec...

Boreyko, A V; Krasavin, E A

2000-01-01

330

Lactic acid fermentation in vegetable juices supplemented with different content of brewer’s yeast autolysate  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

Rakin Marica B.; Baras Josip K.; Vukašinovi? Maja S.

2005-01-01

331

[Attraction of Sphenophorus levis Vaurie adults (Coleoptera: Curculionidae) to vegetal tissues at different conservation levels].  

Science.gov (United States)

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. PMID:20098932

Girón-Pérez, Katherine; Nakano, Octávio; Silva, Amanda C; Oda-Souza, Melissa

2009-01-01

332

Estimation of Herbaceous Fuel Moisture Content Using Vegetation Indices and Land Surface Temperature from MODIS Data  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The monitoring of herbaceous fuel moisture content is a crucial activity in order to assess savanna fire risks. Faced with the difficulty of managing wide areas of vegetated surfaces, remote sensing appears an attractive alternative for terrestrial measurements because of its advantages related to temporal resolution and spatial coverage. Earth observation (EO)-based vegetation indices (VIs) and the ratio between Normalized Difference Vegetation Index (NDVI) and surface temperature (ST) were ...

Momadou Sow; Cheikh Mbow; Christelle Hély; Rasmus Fensholt; Bienvenu Sambou

2013-01-01

333

Vegetation NDVI Linked to Temperature and Precipitation in the Upper Catchments of Yellow River  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Vegetation in the upper catchment of Yellow River is critical for the ecological stability of the whole watershed. The dominant vegetation cover types in this region are grassland and forest, which can strongly influence the eco-environmental status of the whole watershed. The normalized difference vegetation index (NDVI) for grassland and forest has been calculated and its daily correlation models were deduced by Moderate Resolution Imaging Spectroradiometer products on 12 dates in 2000, 200...

Hao, F.; Zhang, X.; Ouyang, W.; Skidmore, A. K.; Toxopeus, A. G.

2012-01-01

334

Recent Declines in Warming and Vegetation Greening Trends over Pan-Arctic Tundra  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Vegetation productivity trends for the Arctic tundra are updated for the 1982–2011 period and examined in the context of land surface temperatures and coastal sea ice. Understanding mechanistic links between vegetation and climate parameters contributes to model advancements that are necessary for improving climate projections. This study employs remote sensing data: Global Inventory Modeling and Mapping Studies (GIMMS) Maximum Normalized Difference Vegetation Index (MaxNDVI), Special Senso...

2013-01-01

335

Lactic acid fermentation in vegetable juices supplemented with different content of brewer’s yeast autolysate  

Directory of Open Access Journals (Sweden)

Full Text Available 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 shown better growth and lactic acid production than L. acidophilus NCDO 1748.

Rakin Marica B.

2005-01-01

336

Effects of different vegetation on temperature in an urban building environment. Micro-scale numerical experiments  

Energy Technology Data Exchange (ETDEWEB)

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.)

Gross, Guenter [Hannover Univ. (Germany). Inst. fuer Meteorologie und Klimatologie

2012-08-15

337

Glycemic index differences of high-fat diets modulate primarily lipid metabolism in murine adipose tissue  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 adipone...

Schothorst, E. M.; Bunschoten, J. E.; Verlinde, E.; Schrauwen, P.; Keijer, J.

2011-01-01

338

The North Atlantic oscillation and European vegetation dynamics  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The relationship between vegetation greenness and the North Atlantic Oscillation (NAO) is assessed over Europe. The study covers the 21-year period from 1982 to 2002 and is based on monthly composites of the Normalised Difference Vegetation Index (NDVI) and Brightness Temperature from the Global Inventory Monitoring and Modelling System (GIMMS) as well as on monthly precipitation from the Global Precipitation Climatology Centre (GPCC). A systematic analysis is first performed of p...

Gouveia, Ce?lia; Trigo, Ricardo M.; Camara, Carlos C.; Libonati, Renata; Pereira, J. M. C.

2008-01-01

339

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

International Nuclear Information System (INIS)

Graphical abstract: Plot of cos ? versus temperature for metal and ceramic surfaces where cos ? rises linearly with increase in temperature. Highlights: ? cos ? of olive oil on different surface materials rises linearly with increase in temperature. ? Slopes are much higher for quasicrystalline and polymers than for ceramics. ? Increase in surface roughness and surface flaws increases surface wettability. ? Contact angle values gave information for grouping easy-clean polymers from other materials. ? Contact angle measurements cannot directly estimate the cleanability of a surface. - Abstract: 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.

2012-12-15

340

Evaluation of the Uptake and Accumulation of Metals by Some Commonly Irrigated Vegetables in Soils Treated with Different Concentrations of these Metals  

Directory of Open Access Journals (Sweden)

Full Text Available The uptake of some trace elements namely, chromium, nickel, cadmium and lead by some vegetables commonly irrigated were studied under glasshouse conditions. Experiments were conducted in plastic pots using some selected vegetables, lettuce (Lactuca sativa, okra (Abelmoschus esculentus and pepper (Capsicum annum grown on sandy loam soils treated with different concentrations of these metals. The treatments investigated include zero application (control, 10, 50 and 100 ?g dm-3 metal applications. In general, each plant showed similar growth responses and tolerance but different metal uptake patterns in the same metal contaminated media for eight weeks. The enrichment factor of each metal in the different parts of the vegetables was highly varied. However, the fruits of pepper were more enriched with these metals than the okra fruits. Despite the concentration of metals used, the plants were still capable of controlling the metal uptake, no matter the concentration of metal solution applied to the soil.

M. Haliru

2009-01-01

 
 
 
 
341

Using the Normalized Difference Water Index (NDWI within a Geographic Information System to Detect Swimming Pools for Mosquito Abatement: A Practical Approach  

Directory of Open Access Journals (Sweden)

Full Text Available Mosquito-borne diseases affect millions of people worldwide. In the United States, since 1999, West Nile Virus (WNV has infected 36,801 people and has caused the deaths of 1,580. In California, since 2002, nearly 3,600 people have been infected with WNV with an additional 124 fatalities. Analyses of remotely- and spatially-based data have proven to facilitate the study of mosquito-borne diseases, including WNV. This study proposes an efficient procedure to identify swimming pools that may serve as potential mosquito habitat. The procedure derives the Normalized Difference Water Index (NDWI from high resolution, multi-spectral imagery to detect the presence of surface water, and then incorporates vector-based data layers within a GIS to identify residential land parcels with detectable water. This study compared the parcels identified as having water (535 with parcels known to have swimming pools (682 resulting in an accuracy of 78.4%. Nineteen of the 147 land parcels with swimming pools had backyards with enough vegetation to obscure the presence of a swimming pool from the satellite. The remaining 128 parcels lacked enough surface water for the NDWI to indicate them as actually having surface water. It is likely then that swimming pools, associated with such parcels, may have enough water in them to provide adequate habitat for mosquitoes, and so field inspection by mosquito abatement personnel would be justified.

Stuart K. McFeeters

2013-07-01

342

Growth, fructification and plastochron index of different branches in the crown of the husk tomato (Physalis ixocarpa Brot.  

Directory of Open Access Journals (Sweden)

Full Text Available The husk tomato (Physalis ixocarpa Brot. is commonly cultivated in Central Mexico for its fruits. The plants of cv. 'Rendidora' show sympodial growth after forming 3-5 internodes in the main axis. From there on, each internode is terminated with a node having one flower bud, one leaf and 2 branches (dichasium type of branching. With the exclusion of the first 3 bifurcations which initiate 4 equal apparent main branches of the plant, each subsequent bifurcation has unequal ramifications: a stronger one which prolongs the apparent main branch, and a weaker one which serves as the origin of an apparent lateral branch. The apparent lateral branches form smaller internodes but these internodes require more time for their growth which is the reason that the plastochron lasts longer in the apparent lateral branches. By forming a smaller number of internodes in the same period of time, the apparent lateral branches reach a lower value of the plastochron index. All apparent lateral branches of a plant produce a greater total number of fruits, but a large proportion of them abscise. Due to this, the harvested fruits come principally from the apparent main branches. The phenology of the husk tomato plant is described. Its short period of development makes possible its cultivation in regions with a limited vegetative period.

Juan M. Brito

1985-09-01

343

The Structural Difference of Shanghai Stock Index before and after 2008: A Copula Based Analysis  

Directory of Open Access Journals (Sweden)

Full Text Available The year 2008 witnessed the greatest joint stock reform and financial crisis in Chinese history. After these two cases, significant changes have taken place in investors’ behaviors worldwide, along with which is the occurrence of structure change in stock market. In this paper, we employ copula model to simulate the joint distribution between Shanghai Stock Index (SSE and Chinese Shanghai Index 300 (CSI 300, to find out structure change in Chinese stock market before and after 2008. From results of empirical studies, we get conclusions that the main nature of Chinese stocks market is symmetric, in both marginal and joint distributions. Via the changes of Copula types, upper and lower tail coefficients and Kendall coefficients, we can measure the structure change in Chinese stock market, and get further conclusion about investors’ behaviors change. Before 2008, there is an equal power in quitting market and longing, while diversified investors adjusted their expectation uniformly after this year. Testing results show that the general dependence structure of CSI 300 and SSE is highly dependent and symmetric in most cases. From the distribution of upper and lower tail coefficients, we can draw the conclusion that stratified investors are mainly focused on two tasks, after this year, to close the position on stocks with high correlated stocks market and to maintain market value of stocks.

Chuan Wu

2012-11-01

344

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)

1983-01-01

345

Variation of combined heat-irradiation effects on cell inactivation in different types of vegetative bacteria  

International Nuclear Information System (INIS)

Combined effects of irradiation and heating on cell inactivation were studied with E. coli K-12 derivatives of different DNA repair capacities and some thermophilic bacteria. With E. coli K-12 mutants log-phase cells of all four strains tested were sensitized to radiation by simultaneous heating. This means that the synergistic interaction between irradiation and heating is independent of pol, uvr and rec mutation. Simultaneous heating was more effective for radiosensitization than heating before or after irradiation. This combination effect was not or only weakly observed with stationary-phase cells. From recovery experiments and sedimentation analysis of DNA from E. coli cells the process of the synergistic interaction may involve the inhibition of the recovery from heat damage and the DNA repair, especially Type II repair. In respect of thermophilic bacteria, it was found that Streptococcus thermophilus becomes more sensitive to radiation under the combined treatment with heating, while other thermophilic strains do not, according to a comparison of the radiosensitivities in terms of the D10 value of the exponential slopes of the survival curves. The latter observation with thermophilic bacteria is in contrast to E. coli. The results of sedimentation analysis of DNA of thermophiles gave unique features. (author)

1977-11-25

346

Heavy-ion effects on yeast: survival and recovery in vegetative cells of different sensitivity  

International Nuclear Information System (INIS)

Wild-type haploid and diploid and radiosensitive haploid yeast strains were exposed to beams of Ar, Kr, Xe, Pb, and U ions of different energies (0.3 MeV/u less than or equal to E/m less than or equal to 8.5 MeV/u) obtained from the UNILAC, Gesellschaft fur Schwerionenforschung (GSI), Darmstadt, Federal Republic of Germany. The LET/sub infinity/ ranged from 2000 to 14,000 keV/?m. The colony-forming ability after immediate plating and after recovery from potentially lethal damage was investigated. The effective inactivation cross sections, calculated from the terminal slopes of the survival curves, were found to increase with Z2/sub eff//#betta#2 at constant #betta# and to increase with #betta# at constant Z2/sub eff//#betta#2. Effects of the central and peripheral regions of the particle tracks could be considered separately. For very heavy particles delayed plating recovery was found to increase with increasing particle speed

1982-01-01

347

Regional Climate Simulations with COSMO-CLM for West Africa using different soil-vegetation-atmosphere-transfer module's (SVAT's)  

Science.gov (United States)

Climate predictions on decadal timescales constitute a new field of research, closing the gap between short-term and seasonal weather predictions and long-term climate projections. Therefore, the Federal Ministry of Education and Research in Germany (BMBF) has recently funded the research program MiKlip (Mittelfristige Klimaprognosen), which aims to create a model system that can provide reliable decadal climate forecasts. Recent studies have suggested that one region with high potential decadal predictability is West Africa. Therefore, the DEPARTURE project (DEcadal Prediction of African Rainfall and ATlantic HURricanE Activity) was established within the MiKlip program to assess the feasibility and the potential added value of regional decadal climate predictions for West Africa. To quantify the potential decadal climate predictability, a multi-model approach with the three different regional climate models REMO, WRF and COSMO-CLM (CCLM) will be realized. The presented research will contribute to DEPARTURE by performing hindcast ensemble simulations with CCLM, based on SST-driven global MPI-ESM-LR simulations. Thereby, one focus is on the dynamic soil-vegetation-climate interaction on decadal timescales. Recent studies indicate that there are significant feedbacks between the land-surface and the atmosphere, which might influence the decadal climate variability substantially. To investigate this connection, three different SVAT's (TERRA_ML, Community Land Model (CLM), and VEG3D) will be coupled with the CCLM. Thus, sensitive model parameters shall be identified, whereby the understanding of important processes might be improved. As a first step, the influence of the model domain on the CCLM results was examined. For this purpose, recent CCLM results from simulations for the official CORDEX domain were compared with CCLM results achieved by using an extended DEPARTURE model domain to about 60°W. This sensitivity analysis was performed with a horizontal resolution of 0.44°. Thereby, the analysis showed that the domain size doesn't affect the quality of the simulation results significantly. The impact of different SVAT's on the model performance is supposed to be higher. To investigate this assumption, TERRA_ML, the standard SVAT implemented in CCLM, is replaced by VEG3D using the OASIS3-MCT coupling software. Compared to TERRA_ML, VEG3D includes an explicit vegetation layer, inducing higher correlations with observations as it has been shown in previous studies. The results of both model configurations are analysed and presented for the DEPARTURE model domain.

Breil, Marcus; Panitz, Hans-Jürgen

2013-04-01

348

Differences in the deposition of radionuclides to leafy vegetables; Unterschiede bei der Ablagerung von Radionukleiden auf verschiedene Blattgemuesearten  

Energy Technology Data Exchange (ETDEWEB)

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 ({sup 131} vertical stroke {sub 2}-portion, particle median, stomata opening, air humidity and temperature). Significant differences were observed for the {sup 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 {sup 134}Cs, 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 {sup 131} vertical stroke than for {sup 134}Cs. 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 {sup 131} vertical stroke and 45% for {sup 134}Cs. (orig.) [German] Um die Variabilitaet zwischen einzelnen Arten zu quantifizieren, wurde in vergleichenden Experimenten in einer Depositionskammer die trockene Ablagerung von elementarem, gasfoermigem Radiojod und partikelgebundenem Radiocaesium auf erntereife Blattgemuesearten untersucht. Die gleichzeitige Exposition von Endivie, Kopfsalat, Pfluecksalat, Gruenkohl, Weisskohl und Spinat fand unter homogenen Bedingungen mit Kontrolle der relevanten Parameter ({sup 131} vertical stroke {sub 2}-Anteil, Partikelmedian, Stomataoeffnung, Luftfeuchte und -temperatur) statt. Bei der (gewichtsbezogenen) Jodablagerung wurden fuer alle Fruehlingsarten signifikante Unterschiede festgestellt: Auf Blattspinat wurde grob 3mal mehr {sup 131} vertical stroke abgelagert als auf Pfluecksalat, 4mal mehr als auf Endievie und 9mal mehr als auf Kopfsalat. Bei Caesium konnte nicht zwischen der Disposition auf Spinat und Pfluecksalat unterschieden werden, auf beide Arten wurde signifikant grob doppelt so viel {sup 134}Cs wie auf Endivie und 3mal so viel wie auf Kopfsalat abgelagert. Bei den Sommerarten wurden fuer alle Spezies signifikante Unterschiede gemessen. In beiden Experimenten ergab sich, dass {sup 131} vertical stroke auf Spinat am meisten deponiert wurde, grob 3mal bzw. 6mal mehr als auf Gruenkohl und 35mal bzw. 100mal mehr als auf Weisskohl. Caesium wurde jedoch am meisten auf Gruenkohl deponiert, gut doppelt so viel wie auf Spinat und 35mal bzw. 80mal so viel wie auf Weisskohl. Auf die geschlossenen Koepfe von Weisskohl und Kopfsalat wurde also immer am wenigsten abgelagert, bei der Gasdeposition erwiesen sich die vielen geoeffneten Stomata bei Spinat als effizienzerhoehend, bei der Partikeldeposition zusaetzlich die gekraeuselten, rauhen Blaetter von Gruenkohl und Endivie. Die Abschaetzung der Depositionsgeschwindigkeiten ergab, dass die Ablagerung von {sup 131} vertical stroke {sub 2} im Mittel etwa eine Groessenordnung effektiver als die von partikulaerem {sup 134}Cs war, wobei allerdings die Joddeposition bei Spinat besonders hoch ausfiel. Die Verdopplung des Partikeldurchmessers bei sonst gleichem Experimentdesign bewirkte nur eine geringe Erhoehung der Deposition. Durch Waschen

Tschiersch, J.; Shinonaga, T.; Heuberger, H. [Technische Univ. Muenchen (Germany). Lehrstuhl fuer Gemuesebau; Bunzl, K.; Pliml, A.; Dietl, F.; Keusch, M.

2003-07-01

349

THEORETICAL EVALUATION OF REFRACTIVE INDEX IN BINARY LIQUID MIXTURES AT DIFFERENT TEMPERATURES  

Directory of Open Access Journals (Sweden)

Full Text Available Refractive indices and densities of the binary mixture pyrrolidinone with propane-1,3-diol have been measured at 303.15, 308.15, 313.15 and 318.15 K over the entire mole fraction range. A comparative study of Arago-Biot (A-B, Eykman (E, Eyring and John (E-J, Gladstone-Dale (G-D, Heller (H, Lorentz-Lorentz (L-L, Newton (N, Oster (Os and Weiner (W relations for predicting the refractive index of a liquid has been carried out to test the validity for the binary mixtures over the entire composition range of pyrrolidinone at four temperatures. Comparision of various mixing rules has been expressed in terms of average percentage deviation

T. Srinivasa Krishna

2014-04-01

350

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

2009-02-01

351

No difference in body weight decrease between a low-glycemic-index and a high-glycemic-index diet but reduced LDL cholesterol after 10-wk ad libitum intake of the low-glycemic-index diet  

DEFF Research Database (Denmark)

Background: The role of glycemic index (GI) in appetite and body-weight regulation is still not clear. Objective: The objective of the study was to investigate the longterm effects of a low-fat. high-carbohydrate diet with either low glycemic index (LGI) or high glycemic index (HGI) on ad libitum energy intake, body weight, and composition, as well as on risk factors for type 2 diabetes and ischemic heart disease in overweight healthy subjects. Design: The study was a 10-wk parallel, randomized, intervention trial with 2 matched groups. The LGI or HGI test foods, given as replacements for the subjects' usual carbohydrate-rich foods, were equal in total energy, energy density, dietary fiber, and macronutrient composition. Subjects were 45 (LGI diet: n = 23; HGI diet: n = 22) healthy overweight [body mass index (in kg/m(2)) : 27.6 +/- 0.2] women aged 20-40 y. Results: Energy intake, mean (+/- SEM) body weight (LGI diet: - 1.9 +/- 0.5 ka: HGI diet: - 1.3 +/- 0.3 kg), and fat mass (LGI diet: - 1.0 +/- 0.4 4: HGI diet: - 0.4 +/- 0.3 kg) decreased over time, but the differences between groups were not significant. No significant differences were observed between groups in fasting serum insulin, homeostasis model assessment for relative insulin resistance, homeostasis model assessment for 0 cell function, triacylglycerol, nonesterified fatty acids, or HDL cholesterol. However, a 10% decrease in LDL cholesterol (P <0.05) and a tendency to a larger decrease in total cholesterol (P = 0.06) were observed with consumption of the LGI diet as compared with the HGI diet. Conclusions: This study does not support the contention that low-fat LGI diets are more beneficial than HGI diets with regard to appetite or body-weight regulation as evaluated over 10 wk. However, it confirms previous findings of a beneficial effect of LGI diets on risk factors for ischemic heart disease.

Sloth, B.; Krog-Mikkelsen, I.

2004-01-01