WorldWideScience

Sample records for subcatchment growing season

  1. Assessment of the Growing Season over the Unimodal Rainfall ...

    African Journals Online (AJOL)

    Most part of Tanzania experiences unimodal rainfall. The characteristics of rainfall such as its onset and cessation dates, dry and wet spell lengths, frequency and number of rainy days can be, used to determine the nature of growing season length of growing season end of season and its geographical variation both ...

  2. Effects of Temperature and Growing Seasons on Crop Water ...

    African Journals Online (AJOL)

    PROF HORSFALL

    ABSTRACT: Water savings can be improved through reducing agricultural water consumption. The crop water requirement (CWR) depends on several factors including temperature and growing seasons. This study investigated the effects of temperature and growing seasons on CWR in Saudi Arabia. Increase in ...

  3. Assessment of the Growing Season Regime Region of Tanzania ...

    African Journals Online (AJOL)

    cessation dates, dry and wet spell lengths, frequency and number of rainy days can be, used to determine the nature of growing season; length of ... Key words: Agrometeorology, dry spells: growing season, Tanzania, unimodal rainfall. Introduction ..... most statistical' text books and in Okoola and. Salano (2002). Positive ...

  4. Effects of temperature and growing seasons on crop water ...

    African Journals Online (AJOL)

    The crop water requirement (CWR) depends on several factors including temperature and growing seasons. This study investigated the effects of temperature and growing seasons on CWR in Saudi Arabia. Increase in temperature by 1°C increased the CWR by 1.9 - 2.9%, 1.9 – 3.0% and 2.2 – 3.8% for dates, alfalfa and ...

  5. Freezing tolerance of wheat cultivars at the early growing season ...

    African Journals Online (AJOL)

    2012-02-28

    Feb 28, 2012 ... Cold stress is a worldwide abiotic stress in temperate regions that affects plant development and yield of winter wheat (Triticum aestivum L.) cultivars and other winter crops. This study was conducted to evaluate the effect of freezing stress at the early growing season on survival and also the relationship.

  6. Freezing tolerance of wheat cultivars at the early growing season ...

    African Journals Online (AJOL)

    Cold stress is a worldwide abiotic stress in temperate regions that affects plant development and yield of winter wheat (Triticum aestivum L.) cultivars and other winter crops. This study was conducted to evaluate the effect of freezing stress at the early growing season on survival and also the relationship between resistances ...

  7. Growing season methane budget of an Inner Mongolian steppe

    Science.gov (United States)

    Liu, Chunyan; Holst, Jirko; Yao, Zhisheng; Brüggemann, Nicolas; Butterbach-Bahl, Klaus; Han, Shenghui; Han, Xingguo; Tas, Bart; Susenbeth, Andreas; Zheng, Xunhua

    We present a methane (CH 4) budget for the area of the Baiyinxile Livestock Farm, which comprises approximately 1/3 of the Xilin river catchment in central Inner Mongolia, P.R. China. The budget calculations comprise the contributions of natural sources and sinks as well as sources related to the main land-use in this region (non-nomadic pastoralism) during the growing season (May-September). We identified as important CH 4 sources floodplains (mean 1.55 ± 0.97 mg CH 4-C m -2 h -1) and domestic ruminants, which are mainly sheep in this area. Within the floodplain significant differences between investigated positions were detected, whereby only positions close-by the river or bayous emitted large amounts of CH 4 (mean up to 6.21 ± 1.83 mg CH 4-C m -2 h -1). Further CH 4 sources were sheepfolds (0.08-0.91 mg CH 4-C m -2 h -1) and pasture faeces (1.34 ± 0.22 mg CH 4-C g -1 faeces dry weight), but they did not play a significant role for the CH 4 budget. In contrast, dung heaps were not a net source of CH 4 (0.0 ± 0.2 for an old and 0.0 ± 0.3 μg CH 4-C kg -1 h -1 for a new dung heap). Trace gas measurements along two landscape transects (volcano, hill slope) revealed expectedly a mean CH 4 uptake (volcano: 76.5 ± 4.3; hill: 28.3 ± 5.3 μg CH 4-C m -2 h -1), which is typical for the aerobic soils in this and other steppe ecosystems. The observed fluxes were rarely influenced by topography. The CH 4 emissions from the floodplain and the sheep were not compensated by the CH 4 oxidation of aerobic steppe soils and thus, this managed semi-arid grassland did not serve as a terrestrial sink, but as a source for this globally important greenhouse gas. The source strength amounted to 1.5-3.6 kg CH 4-C ha -1 during the growing season, corresponding to 3.5-8.7 kg C ha -1 yr -1.

  8. Seasonal and cumulative loblolly pine development under two stand density and fertility levels through four growing seasons

    Science.gov (United States)

    James D. Haywood

    1994-01-01

    A loblolly pine stand was subjected to two cultural treatments to determine treatment effects in the 9th through 12th growing seasons. Thining resulted in less spring height growth in the 9th and 10th growing seasons than no thinning, but thinning resulted in more diameter growth each year. Fertilization increased height and diameter growth beginning in the 10th...

  9. 317/319 phytoremediation site monitoring report - 2005 growing season.

    Energy Technology Data Exchange (ETDEWEB)

    Negri, M. C.; Gopalakrishnan, G.; Energy Systems

    2006-03-31

    In 1999, Argonne National Laboratory (ANL) designed and installed a series of engineered plantings consisting of a vegetative cover system and approximately 800 hybrid poplars and willows rooting at various predetermined depths. The plants were installed using various methods including Applied Natural Science's TreeWell{reg_sign} system. The goal of the installation was to protect downgradient surface and groundwater by hydraulic control of the contaminated plume by intercepting the contaminated groundwater with the tree roots, removing moisture from the upgradient soil area, reducing water infiltration, preventing soil erosion, degrading and/or transpiring the residual volatile organic compounds (VOCs), and removing tritium from the subsoil and groundwater. This report presents the results of the monitoring activities conducted by Argonne's Energy Systems Division (ES) in the growing season of 2005. Monitoring of the planted trees began soon after the trees were installed in 1999 and has been conducted every summer since then. As the trees grew and consolidated their growth into the contaminated soil and groundwater, their exposure to the contaminants was progressively shown through tissue sampling. However, as trees grow larger, some of the findings obtained in the early years when trees were much smaller may not hold true now and need to be verified again. During the 2005 sampling campaign, data from the French Drain area confirmed the results obtained in 2004 and earlier, and the previously found correlation between soil and branch concentrations. During the 2005 summer, studies under controlled conditions (cartridges) have shown a generally linear dose response of PCE uptake, and have also shown that tree concentrations of PCE decrease after flushing with clean water in short times when trees are exposed to low levels of the contaminant. This data proves that tree concentrations are transient, and that with proper time levels can return close to

  10. Performance of machinery in potato production in one growing season

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, K.; Jensen, A.L.; Bochtis, D.D.; Sørensen, C.G.

    2015-07-01

    Statistics on the machinery performance are essential for farm managers to make better decisions. In this paper, the performance of all machineries in five sequential operations, namely bed forming, stone separation, planting, spraying and harvesting in the potato production system, were investigated during one growing season. In order to analyse and decompose the recorded GPS data into various time and distance elements for estimation of the machinery performance, an automatic GPS analysis tool was developed. The field efficiency and field capacity were estimated for each operation. Specifically, the measured average field efficiency was 71.3% for bed forming, 68.5% for stone separation, 40.3% for planting, 69.7% for spraying, and 67.4% for harvesting. The measured average field capacities were 1.46 ha/h, 0.53 ha/h, 0.47 ha/h, 10.21 ha/h, 0.51 ha/h, for the bed forming, stone separation, planting, spraying, and harvesting operations, respectively. These results deviate from the corresponding estimations calculated based on norm data from the American Society of Agricultural and Biological Engineers (ASABE). The deviations indicate that norms provided by ASABE cannot be used directly for the prediction of performance of the machinery used in this work. Moreover, the measured data of bed forming and stone separation could be used as supplementary data for the ASABE which does not provide performance norms for these two operations. The gained results can help farm managers to make better management and operational decisions that result in potential improvement in productivity and profitability as well as in potential environmental benefits. (Author)

  11. Performance of machinery in potato production in one growing season

    Directory of Open Access Journals (Sweden)

    Kun Zhou

    2015-12-01

    Full Text Available Statistics on the machinery performance are essential for farm managers to make better decisions. In this paper, the performance of all machineries in five sequential operations, namely bed forming, stone separation, planting, spraying and harvesting in the potato production system, were investigated during one growing season. In order to analyse and decompose the recorded GPS data into various time and distance elements for estimation of the machinery performance, an automatic GPS analysis tool was developed. The field efficiency and field capacity were estimated for each operation. Specifically, the measured average field efficiency was 71.3% for bed forming, 68.5% for stone separation, 40.3% for planting, 69.7% for spraying, and 67.4% for harvesting. The measured average field capacities were 1.46 ha/h, 0.53 ha/h, 0.47 ha/h, 10.21 ha/h, 0.51 ha/h, for the bed forming, stone separation, planting, spraying, and harvesting operations, respectively. These results deviate from the corresponding estimations calculated based on norm data from the American Society of Agricultural and Biological Engineers (ASABE. The deviations indicate that norms provided by ASABE cannot be used directly for the prediction of performance of the machinery used in this work. Moreover, the measured data of bed forming and stone separation could be used as supplementary data for the ASABE which does not provide performance norms for these two operations. The gained results can help farm managers to make better management and operational decisions that result in potential improvement in productivity and profitability as well as in potential environmental benefits.

  12. Effects of Continuous Flooding in No-rice Growing Season on CH4 and CO2 Emissions of Rice Growing Season with Straw Returning

    Directory of Open Access Journals (Sweden)

    XU Xiang-yu

    2017-03-01

    Full Text Available Straw returning is a straw utilization pattern which is widely promoted in China. It can increase the soil organic carbon and fertility, but straw returning also increase the CH4 and CO2 emissions. The effects of continuous flooding in no rice growing season on CH4 and CO2 emission in rice season with straw returning is not clear. This study was conducted with two different water managements in no rice growing season, one was the middle rice-natural drainage (RD and another was the middle rice-continuous flooding (RW. The aim was to investigate the characteristic of CH4 and CO2 emission flux in rice season under different water management with straw returning, and to provide data support for accurate assessment of paddy greenhouse gas emissions. The results showed that RD significantly reduced the CH4 accumulation emission flux in rice growing season compared with the RW, and 80% total CH4 emission flux in rice growing season was emission before the first drainage whether RD or RW. RW could cutdown the CO2 accumulation emission flux in rice growing season compared with RD, and about 60% total CO2 emission flux in rice growing season was emission after the first drainage whether RD or RW. RW reduced the soil NO3--N, NH4+-N and DOC concentration in rice growing season, and decreased the Eh value at 10 cm soil layer, but increased the acetic acid concentration. This might be the main reason of increasing the CH4 accumulation emission flux from RD.

  13. Remotely Sensed Northern Vegetation Response to Changing Climate: Growing Season and Productivity Perspective

    Science.gov (United States)

    Ganguly, S.; Park, Taejin; Choi, Sungho; Bi, Jian; Knyazikhin, Yuri; Myneni, Ranga

    2016-01-01

    Vegetation growing season and maximum photosynthetic state determine spatiotemporal variability of seasonal total gross primary productivity of vegetation. Recent warming induced impacts accelerate shifts on growing season and physiological status over Northern vegetated land. Thus, understanding and quantifying these changes are very important. Here, we first investigate how vegetation growing season and maximum photosynthesis state are evolved and how such components contribute on inter-annual variation of seasonal total gross primary productivity. Furthermore, seasonally different response of northern vegetation to changing temperature and water availability is also investigated. We utilized both long-term remotely sensed data to extract larger scale growing season metrics (growing season start, end and duration) and productivity (i.e., growing season summed vegetation index, GSSVI) for answering these questions. We find that regionally diverged growing season shift and maximum photosynthetic state contribute differently characterized productivity inter-annual variability and trend. Also seasonally different response of vegetation gives different view of spatially varying interaction between vegetation and climate. These results highlight spatially and temporally varying vegetation dynamics and are reflective of biome-specific responses of northern vegetation to changing climate.

  14. Impact of climate change on mid-twenty-first century growing seasons in Africa

    Energy Technology Data Exchange (ETDEWEB)

    Cook, Kerry H.; Vizy, Edward K. [The University of Texas at Austin, Department of Geological Sciences, Jackson School of Geosciences, Austin, TX (United States)

    2012-12-15

    Changes in growing seasons for 2041-2060 across Africa are projected using a regional climate model at 90-km resolution, and confidence in the predictions is evaluated. The response is highly regional over West Africa, with decreases in growing season days up to 20% in the western Guinean coast and some regions to the east experiencing 5-10% increases. A longer growing season up to 30% in the central and eastern Sahel is predicted, with shorter seasons in parts of the western Sahel. In East Africa, the short rains (boreal fall) growing season is extended as the Indian Ocean warms, but anomalous mid-tropospheric moisture divergence and a northward shift of Sahel rainfall severely curtails the long rains (boreal spring) season. Enhanced rainfall in January and February increases the growing season in the Congo basin by 5-15% in association with enhanced southwesterly moisture transport from the tropical Atlantic. In Angola and the southern Congo basin, 40-80% reductions in austral spring growing season days are associated with reduced precipitation and increased evapotranspiration. Large simulated reductions in growing season over southeastern Africa are judged to be inaccurate because they occur due to a reduction in rainfall in winter which is over-produced in the model. Only small decreases in the actual growing season are simulated when evapotranspiration increases in the warmer climate. The continent-wide changes in growing season are primarily the result of increased evapotranspiration over the warmed land, changes in the intensity and seasonal cycle of the thermal low, and warming of the Indian Ocean. (orig.)

  15. Reduced early growing season freezing resistance in alpine treeline plants under elevated atmospheric CO2.

    NARCIS (Netherlands)

    Martin, M.; Gavazov, K.S.; Körner, S.; Rixen, C.

    2010-01-01

    The frequency of freezing events during the early growing season and the vulnerability to freezing of plants in European high-altitude environments could increase under future atmospheric and climate change. We tested early growing season freezing sensitivity in 10 species, from four plant

  16. Lengthening of the growing season in wheat and maize producing regions

    Directory of Open Access Journals (Sweden)

    Brigitte Mueller

    2015-09-01

    Full Text Available Human-induced increases in atmospheric greenhouse gas concentrations have led to rising global temperatures. Here we investigate changes in an annual temperature-based index, the growing season length, defined as the number of days with temperature above 5 °C. We show that over extratropical regions where wheat and maize are harvested, the increase in growing season length from 1956 to 2005 can be attributed to increasing greenhouse gas concentrations. Our analyses also show that climate change has increased the probability of extremely long growing seasons by a factor of 25, and decreased the probability of extremely short growing seasons. A lengthening of the growing season in regions with these mostly rain-fed crops could improve yields, provided that water availability does not become an issue. An expansion of areas with more than 150 days of growing season into the northern latitudes makes more land potentially available for planting wheat and maize. Furthermore, double-cropping can become an alternative to current practices in areas with very long growing seasons which are also shown to increase with a warming climate. These results suggest that there is a strong impact of anthropogenic climate change on growing season length. However, in some regions and with further exacerbated climate change, high temperatures may already be or may become a limiting factor for plant productivity.

  17. World climate patterns in grassland and savanna and their relation to growing seasons

    Directory of Open Access Journals (Sweden)

    R. Kirk Steinhorst

    1977-12-01

    Full Text Available The climate at eleven IBP savanna or grassland study sites from five continents are described and principal components analysis is used to compare them. A multivariate linear discriminant function based on mean monthly precipitation, mean monthly temperature, latitude and altitude, is used to predict the length of the growing season at each site. At most sites, the actual and predicted start and end of the growing season agreed closely. It is concluded that growing season on a world-wide basis may be predicted fairly reliably from a small number of abiotic variables by means of a multivariate discriminant function.

  18. Change in Length of Growing Season by State, 1895-2015

    Data.gov (United States)

    U.S. Environmental Protection Agency — This map shows the total change in length of the growing season, time of first fall frost and time of last spring frost from 1895 to 2015 for each of the contiguous...

  19. New England observed and predicted growing season maximum stream/river temperature points

    Data.gov (United States)

    U.S. Environmental Protection Agency — The shapefile contains points with associated observed and predicted growing season maximum stream/river temperatures in New England based on a spatial statistical...

  20. New England observed and predicted Julian day of maximum growing season stream/river temperature points

    Data.gov (United States)

    U.S. Environmental Protection Agency — The shapefile contains points with associated observed and predicted Julian day of maximum growing season stream/river temperatures in New England based on a spatial...

  1. Pan-Arctic linkages between snow accumulation and growing season air temperature, soil moisture and vegetation

    Science.gov (United States)

    Luus, K. A.; Gel, Y.; Lin, J. C.; Kelly, R. E. J.; Duguay, C. R.

    2013-01-01

    Arctic field studies have indicated that the air temperature, soil moisture and vegetation at a site influence the quantity of snow accumulated, and that snow accumulation can alter growing season soil moisture and vegetation. Climate change is predicted to bring about warmer air temperatures, greater snow accumulation and northward movements of the shrub and tree lines. Understanding the response of northern environments to changes in snow and growing season land surface characteristics requires: (1) insights into the present-day linkages between snow and growing season land surface characteristics; and (2) the ability to continue to monitor these associations over time across the vast pan-Arctic. The objective of this study was therefore to examine the pan-Arctic (north of 60° N) linkages between two temporally distinct data products created from AMSR-E satellite passive microwave observations: GlobSnow snow water equivalent, and NTSG (growing season air temperature, soil moisture and vegetation transmissivity). Due to the complex and interconnected nature of processes determining snow and growing season land surface characteristics, these associations were analyzed using the modern non-parametric technique of Alternating Conditional Expectations (ACE), as this approach does not impose a predefined analytic form. Findings indicate that regions with lower vegetation transmissivity (more biomass) at the start and end of the growing season tend to accumulate less snow at the start and end of the snow season, possibly due to interception and shading. Warmer air temperatures at the start and end of the growing season were associated with diminished snow accumulation at the start and end of the snow season. High latitude sites with warmer mean annual growing season temperatures tended to accumulate more snow, probably due to the greater availability of water vapor for snow season precipitation at warmer locations. Regions with drier soils preceding snow onset tended

  2. Technological quality of common bean grains obtained in different growing seasons

    Directory of Open Access Journals (Sweden)

    Eliana Francischinelli Perina

    2014-03-01

    Full Text Available The traits that provide technological quality to common bean grains exhibit genetic and environmental variation and variation in the genotype x environment interaction. In this context, the aim of this study was to assess the effect of different periods of the growing season on the technological quality of common bean grains. The experiment was conducted with 25 bean genotypes (carioca [beige with brown stripes] and black commercial group that are part of the Value for Cultivation and Use (Valor de Cultivo e Uso - VCU trials in three growing seasons, namely, the 2009/2010 rainy season, the 2010/2011 dry season and the 2010/2011 winter season, in a randomized block experimental design with three replications in which the following items were assessed: cooking time (CT, water absorption capacity before cooking (Peanc and after cooking (Peapc, percentage of whole grains (PWG, total soluble solids in the broth (TSSb, volume expansion before cooking (EXPVbc and after cooking (EXPVac, and dry grain density (DD, grain density after maceration (SD and grain density after cooking (CD. Assessments showed that the different growing seasons for obtaining grains for the purpose of analysis of technological quality have an effect on the results and on differentiation among genotypes, indicating genotype x environment interaction. They also showed that the genotypes C2-1-6-1, C4-8-1-1, LP04-03, IAC-Imperador, P5-4-4-1 and Pr11-6-4-1-2 had the best results in relation to cooking time in the mean values of the three growing seasons. The use of early selection based on phenotypic correlations that exist among the technological features is not expressive, due to the variation of magnitude among the different growing seasons.

  3. A synthesis of growing-season and annual methane emissions among temperate, boreal, and arctic wetlands

    Science.gov (United States)

    Treat, Claire

    2017-04-01

    Wetlands are the largest natural source of methane to the atmosphere, but predicting methane emissions from wetlands using process-based modeling remains challenging due to the decoupling between production and emission. Furthermore, methane emissions are highly variable among sites, years, and temporal scales due to differences in production, oxidation, and transport pathways. Here, I synthesize growing season, non-growing season, and annual methane emissions from chamber and eddy-covariance measurements for >150 sites in undisturbed temperate, boreal, and arctic wetlands and adjacent uplands. I compare the magnitude of fluxes among regions, wetland classifications, vegetation classifications, environmental variables, and measurement methods. Growing season measurements were most abundant in bogs, fens, and tundra sites, while marshes, swamps, and permafrost thaw features were relatively undersampled. Methane emissions were largest from intermediate and rich fens (> 15 g CH4 m-2 y-1) and lowest from upland mineral soils and polygonal tundra (≤ 3 g CH4 m-2 y-1). Non-growing season emissions accounted for 20% of annual methane emissions. Across all sites, there were no significant differences in growing season methane emissions between autochambers, manual chambers, and eddy covariance. These results provide constraints for methane emissions from temporal, boreal, and arctic wetlands utilizing the numerous flux measurements conducted over the past 25 years.

  4. Trends in the Start of the Growing Season in Fennoscandia 1982–2011

    Directory of Open Access Journals (Sweden)

    Stein Rune Karlsen

    2013-09-01

    Full Text Available Global temperature is increasing, and this is affecting the vegetation phenology in many parts of the world. In Fennoscandia, as well as Northern Europe, the advances of phenological events in spring have been recorded in recent decades. In this study, we analyzed the start of the growing season within five different vegetation regions in Fennoscandia using the 30-year Global Inventory Modeling and Mapping Studies (GIMMS NDVI3g dataset. We applied a previously developed pixel-specific Normalized Difference Vegetation Index (NDVI threshold method, adjusted it to the NDVI3g data and analyzed trends within the different regions. Results show a warming trend with an earlier start of the growing season of 11.8 ± 2.0 days (p < 0.01 for the whole area. However, there are large regional differences, and the warming/trend towards an earlier start of the growing season is most significant in the southern regions (19.3 ± 4.7 days, p < 0.01 in the southern oceanic region, while the start was stable or modest earlier (two to four days; not significant in the northern regions. To look for temporal variations in the trends, we divided the 30-year period into three separate decadal time periods. Results show significantly more change/trend towards an earlier start of the growing season in the first period compared to the two last. In the second and third period, the trend towards an earlier start of the growing season slowed down, and in two of the regions, the trend towards an earlier start of the growing season was even reversed during the last decade.

  5. Population genetics of freeze tolerance among natural populations of Populus balsamifera across the growing season.

    Science.gov (United States)

    Menon, Mitra; Barnes, William J; Olson, Matthew S

    2015-08-01

    Protection against freeze damage during the growing season influences the northern range limits of plants. Freeze tolerance and freeze avoidance are the two major freeze resistance strategies. Winter survival strategies have been extensively studied in perennials, but few have addressed them and their genetic basis during the growing season. We examined intraspecific phenotypic variation in freeze resistance of Populus balsamifera across latitude and the growing season. To investigate the molecular basis of this variation, we surveyed nucleotide diversity and examined patterns of gene expression in the poplar C-repeat binding factor (CBF) gene family. Foliar freeze tolerance exhibited latitudinal and seasonal variation indicative of natural genotypic variation. CBF6 showed signatures of recent selective sweep. Of the 46 SNPs surveyed across the six CBF homologs, only CBF2_619 exhibited latitudinal differences consistent with increased freeze tolerance in the north. All six CBF genes were cold inducible, but showed varying patterns of expression across the growing season. Some Poplar CBF homologs exhibited patterns consistent with historical selection and clinal variation in freeze tolerance documented here. However, the CBF genes accounted for only a small amount of the variation, indicating that other genes in this and other molecular pathways likely play significant roles in nature. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  6. Relationships between storage protein composition, protein content, growing season and flour quaility of bread wheat

    DEFF Research Database (Denmark)

    Faergestad, E.M.; Flaete, N.E.S.; Magnus, E.M.

    2004-01-01

    The storage protein composition from the Glu-1, Glu-3 and Gli-1 loci encoding high and low molecular weight glutenin subunits (HMW-GS and LMW-GS) and gliadins, respectively, was determined on 30 wheat (T aestivum L) genotypes from three growing seasons. The gliadins and the LMW-GS were identified...... of the protein alleles, the protein content and the growing seasons are related to flour quality. The year of growth had a large impact on mixograph peak time. When predicting mixograph peak time from the presence or absence of significant proteins and the year of growth, 70% of the variability in mixograph peak...

  7. Reach-scale river metabolism across contrasting sub-catchment geologies: Effect of light and hydrology.

    Science.gov (United States)

    Rovelli, Lorenzo; Attard, Karl M; Binley, Andrew; Heppell, Catherine M; Stahl, Henrik; Trimmer, Mark; Glud, Ronnie N

    2017-11-01

    We investigated the seasonal dynamics of in-stream metabolism at the reach scale (∼ 150 m) of headwaters across contrasting geological sub-catchments: clay, Greensand, and Chalk of the upper River Avon (UK). Benthic metabolic activity was quantified by aquatic eddy co-variance while water column activity was assessed by bottle incubations. Seasonal dynamics across reaches were specific for the three types of geologies. During the spring, all reaches were net autotrophic, with rates of up to 290 mmol C m-2 d-1 in the clay reach. During the remaining seasons, the clay and Greensand reaches were net heterotrophic, with peak oxygen consumption of 206 mmol m-2 d-1 during the autumn, while the Chalk reach was net heterotrophic only in winter. Overall, the water column alone still contributed to ∼ 25% of the annual respiration and primary production in all reaches. Net ecosystem metabolism (NEM) across seasons and reaches followed a general linear relationship with increasing stream light availability. Sub-catchment specific NEM proved to be linearly related to the local hydrological connectivity, quantified as the ratio between base flow and stream discharge, and expressed on a timescale of 9 d on average. This timescale apparently represents the average period of hydrological imprint for carbon turnover within the reaches. Combining a general light response and sub-catchment specific base flow ratio provided a robust functional relationship for predicting NEM at the reach scale. The novel approach proposed in this study can help facilitate spatial and temporal upscaling of riverine metabolism that may be applicable to a broader spectrum of catchments.

  8. USDA Cranberry Entomology Laboratory (CEL) research priorities in the 2016 growing season

    Science.gov (United States)

    Research priorities during the 2016 growing season will be focused on 1) discovery and screening of native WI nematodes as bio-control agents, and 2) continued refinement of the drone-deployed mating disruption system. Extramural funding will be needed for both, and the degree of funding will dictat...

  9. Fruit characteristics in walnut tree population in relation to growing season onset

    Directory of Open Access Journals (Sweden)

    Miletić Rade

    2010-01-01

    Full Text Available The objective of walnut selection is to obtain promising genotypes characterized by later growing season onset, shorter period of vegetation, resistance to diseases, stable fruit productivity and high fruit quality. Aiming at obtaining genotypes with favorable properties, in five localities of Eastern Serbia, where walnut is widely grown, we studied the correlation among growing season onset on the one hand, and major pomological properties and fruit quality on the other. In the studied population, trees with early growing season onset and fruit mass up to 8.0 g (30.1% were predominant, whereas those with late growing season onset were in minority, fruit mass ranging from 10.1 to 12 g (0.07%. Kernel ratio was highest in the former (20.69%, and the lowest in the latter (0.07%. Similar was observed in oil and raw proteins content in kernel which was highest in fruits of early trees (33.62%, 47,55%, while it was remarkably lower in late ones (0.72%, 0.49%. The obtained results suggest that the studied population was dominated by early trees and unfavorable or less favorable fruit properties. In spite of that, we evidenced some trees with favorable properties which can be used in breeding as donors of useful genes.

  10. The flux of ozone to a maize crop and the underlying soil during a growing season

    NARCIS (Netherlands)

    Pul, van W.A.J.

    1992-01-01

    To observe the flux or deposition of ozone above a maize crop, experiments were carried out during the growing season of maize in 1988. The flux of ozone was determined using meteorological techniques. The measurements used in the present study were carried out under atmospheric conditions

  11. Management of Rice Fields for Birds during the Non-growing Season

    NARCIS (Netherlands)

    Elphick, Chris S.; Taft, Oriane; Lourenco, Pedro M.

    2010-01-01

    Fields planted with rice (Oryza saliva) are used by a wide variety of bird species during the non-growing season and play an important conservation role in many parts of the world. Management of fields affects the variety and number of birds that use them, and a thorough understanding of these

  12. Planting geometry and growing season effects on the growth and yield of dryland cotton

    Science.gov (United States)

    The declining Ogallala Aquifer beneath the Southern High Plains may necessitate dryland crop production and cotton (Gossypium hirsutum L.) is a well-adapted and potentially profitable alternative crop. The limited growing season duration of the Texas Panhandle and southwestern Kansas, however, impos...

  13. Effects of urban green infrastructure (UGI) on local outdoor microclimate during the growing season

    NARCIS (Netherlands)

    Wang, Yafei; Bakker, Frank; Groot, de Rudolf; Wörtche, Heinrich; Leemans, Rik

    2015-01-01

    This study analyzed how the variations of plant area index (PAI) and weather conditions alter the influence of urban green infrastructure (UGI) on microclimate. To observe how diverse UGIs affect the ambient microclimate through the seasons, microclimatic data were measured during the growing

  14. Crop water stress maps for an entire growing season from visible and thermal UAV imagery

    DEFF Research Database (Denmark)

    Hoffmann, Helene; Jensen, Rasmus; Thomsen, Anton

    2016-01-01

    This study investigates whether a water deficit index (WDI) based on imagery from unmanned aerial vehicles (UAVs) can provide accurate crop water stress maps at different growth stages of barley and in differing weather situations. Data from both the early and late growing season are included...... to investigate whether the WDI has the unique potential to be applicable both when the land surface is partly composed of bare soil and when crops on the land surface are senescing. The WDI differs from the more commonly applied crop water stress index (CWSI) in that it uses both a spectral vegetation index (VI...... season because at this stage the remote sensing data represent crop water availability to a greater extent than they do in the early growing season, and because the WDI accounts for areas of ripe crops that no longer have the same need for irrigation. WDI maps can potentially serve as water stress maps...

  15. Nonvascular contribution to ecosystem NPP in a subarctic heath during early and late growing season

    DEFF Research Database (Denmark)

    Campioli, Matteo; Samson, Roeland; Michelsen, Anders

    2009-01-01

    Bryophytes and lichens abound in many arctic ecosystems and can contribute substantially to the ecosystem net primary production (NPP). Because of their growth seasonality and their potential for growth out of the growing season peak, bryophyte and lichen contribution to NPP may be particularly...... significant when vascular plants are less active and ecosystems act as a source of carbon (C). To clarify these dynamics, nonvascular and vascular aboveground NPP was compared for a subarctic heath during two contrasting periods of the growing season, viz. early-mid summer and late summer-early autumn....... Nonvascular NPP was determined by assessing shoot biomass increment of three moss species (Hylocomium splendens, Pleurozium schreberi and Dicranum elongatum) and by scaling to ecosystem level using average standing crop. For D. elongatum, these estimates were compared with production estimates obtained from...

  16. Snowmelt timing, phenology, and growing season length in conifer forests of Crater Lake National Park, USA

    Science.gov (United States)

    O'Leary, Donal S.; Kellermann, Jherime L.; Wayne, Chris

    2017-09-01

    Anthropogenic climate change is having significant impacts on montane and high-elevation areas globally. Warmer winter temperatures are driving reduced snowpack in the western USA with broad potential impacts on ecosystem dynamics of particular concern for protected areas. Vegetation phenology is a sensitive indicator of ecological response to climate change and is associated with snowmelt timing. Human monitoring of climate impacts can be resource prohibitive for land management agencies, whereas remotely sensed phenology observations are freely available at a range of spatiotemporal scales. Little work has been done in regions dominated by evergreen conifer cover, which represents many mountain regions at temperate latitudes. We used moderate resolution imaging spectroradiometer (MODIS) data to assess the influence of snowmelt timing and elevation on five phenology metrics (green up, maximum greenness, senescence, dormancy, and growing season length) within Crater Lake National Park, Oregon, USA from 2001 to 2012. Earlier annual mean snowmelt timing was significantly correlated with earlier onset of green up at the landscape scale. Snowmelt timing and elevation have significant explanatory power for phenology, though with high variability. Elevation has a moderate control on early season indicators such as snowmelt timing and green up and less on late-season variables such as senescence and growing season length. PCA results show that early season indicators and late season indicators vary independently. These results have important implications for ecosystem dynamics, management, and conservation, particularly of species such as whitebark pine (Pinus albicaulis) in alpine and subalpine areas.

  17. Soil microbial biomass alterations during the maize silage growing season relative to tillage method

    Energy Technology Data Exchange (ETDEWEB)

    Staley, T.E.

    1999-12-01

    Tillage method can significantly alter soil microbial populations and activities. Although considerable literature exists on microbial and soil chemical alterations under various tillage methods, little information exists on soil microbial biomass C (SMB) alterations during the growing season, and especially on the relationship of SMB to crop N use. The objective of this study was to determine the effect of notillage (NT) or conventional tillage (CT), and soil location, on SMB during the growing season. A maize (Zea mays L.) silage/{sup 15}N field experiment, under NT or CT for 3 yr before this study, was used during the fourth growing season. Averaged over sampling times and location (within-row or between-row), SMB in the 0- to 3.8-cm and 3.8- to 7.5-cm soil layers under NT was 87 and 33% greater, respectively, than under CT. Linear regression of soil surface layer (0--3.8 cm) SMB on day-of-year revealed a significant (P {le} 0.10) relationship only within-row and under NT, with a 29% SMB decrease during the growing season. Similar regressions for the other layers and treatments were significant (P > 0.10) or had small seasonal differences. SMB was consistently higher in the between-row locations under both tillage methods. Despite substantial tillage method-induced differences in SMB (50% overall, accompanied by small differential seasonal differences) in the more surficial layers, these alterations appear to have been of little practical consequence, since previous work on these plots revealed essentially no differences in silage utilization of either fertilizer N or soil N relative to tillage method. Thus, the importance of SMB in significantly affecting crop N use in this within-row, banded, maize silage system is questioned.

  18. Arbuscular mycorrhizal fungal networks vary throughout the growing season and between successional stages.

    Directory of Open Access Journals (Sweden)

    Alison Elizabeth Bennett

    Full Text Available To date, few analyses of mutualistic networks have investigated successional or seasonal dynamics. Combining interaction data from multiple time points likely creates an inaccurate picture of the structure of networks (because these networks are aggregated across time, which may negatively influence their application in ecosystem assessments and conservation. Using a replicated bipartite mutualistic network of arbuscular mycorrhizal (AM fungal-plant associations, detected using large sample numbers of plants and AM fungi identified through molecular techniques, we test whether the properties of the network are temporally dynamic either between different successional stages or within the growing season. These questions have never been directly tested in the AM fungal-plant mutualism or the vast majority of other mutualisms. We demonstrate the following results: First, our examination of two different successional stages (young and old forest demonstrated that succession increases the proportion of specialists within the community and decreases the number of interactions. Second, AM fungal-plant mutualism structure changed throughout the growing season as the number of links between partners increased. Third, we observed shifts in associations between AM fungal and plant species throughout the growing season, potentially reflecting changes in biotic and abiotic conditions. Thus, this analysis opens up two entirely new areas of research: 1 identifying what influences changes in plant-AM fungal associations in these networks, and 2 what aspects of temporal variation and succession are of general importance in structuring bipartite networks and plant-AM fungal communities.

  19. The Effect of Agricultural Growing Season Change on Market Prices in Africa

    Science.gov (United States)

    deBeurs, K.M.; Brown, M. E.

    2013-01-01

    Local agricultural production is a key element of food security in many agricultural countries in Africa. Climate change and variability is likely to adversely affect these countries, particularly as they affect the ability of smallholder farmers to raise enough food to feed themselves. Seasonality influences farmers' decisions about when to sow and harvest, and ultimately the success or failure of their crops. At a 2009 conference in the United Kingdom hosted by the Institute of Development Studies, Jennings and Magrath (2009) described farmer reports from East Asia, South Asia, Southern Africa, East Africa and Latin America. Farmers indicate significant changes in the timing of rainy seasons and the pattern of rains within seasons, including: More erratic rainfall, coming at unexpected times in and out of season; Extreme storms and unusually intense rainfall are punctuated by longer dry spells within the rainy season; Increasing uncertainty as to the start of rainy seasons in many areas; Short or transitional second rainy seasons are becoming stronger than normal or are disappearing altogether. These farmer perceptions of change are striking in that they are geographically widespread and are remarkably consistent across diverse regions (Jennings and Magrath, 2009). The impact of these changes on farmers with small plots and few resources is large. Farming is becoming riskier because of heat stress, lack of water, pests and diseases that interact with ongoing pressures on natural resources. Lack of predictability in the start and length of the growing season affects the ability of farmers to invest in appropriate fertilizer levels or improved, high yielding varieties. These changes occur at the same time as the demand for food is rising and is projected to continue to rise for the next fifty years (IAASTD, 2008). Long-term data records derived from satellite remote sensing can be used to verify these reports, providing necessary analysis and documentation required

  20. A Comparison of Thermal Growing Season Indices for the Northern China during 1961–2015

    Directory of Open Access Journals (Sweden)

    Linli Cui

    2017-01-01

    Full Text Available Vegetation phenology is one of the most direct and sensitive indicators of terrestrial ecosystem in response to climate change. Based on daily mean air temperature at 877 meteorological stations over northern China from 1961 to 2015, the correlations and differences for different definitions of the growing season parameters (start, end, and length of the growing season were investigated, and results show that higher correlations of 0.81–0.93 are found when indices which do not consider frost are compared with those of the same length which include the frost criteria, and lower correlations of 0.63–0.79 are observed when the length of indices is different and one of the indices includes the frost criteria or EI 3 (10 d < 5°C is included. Lower correlations and larger differences are generally observed in the eastern and northwestern parts while higher correlation and smaller difference appeared in the northeastern and southwestern parts of northern China; thus the applicability comparison and selection of different definitions have important influence on the identifying and counting of the timing and length of the growing season in the eastern and northwestern regions of northern China.

  1. Winter climate change affects growing-season soil microbial biomass and activity in northern hardwood forests.

    Science.gov (United States)

    Durán, Jorge; Morse, Jennifer L; Groffman, Peter M; Campbell, John L; Christenson, Lynn M; Driscoll, Charles T; Fahey, Timothy J; Fisk, Melany C; Mitchell, Myron J; Templer, Pamela H

    2014-11-01

    Understanding the responses of terrestrial ecosystems to global change remains a major challenge of ecological research. We exploited a natural elevation gradient in a northern hardwood forest to determine how reductions in snow accumulation, expected with climate change, directly affect dynamics of soil winter frost, and indirectly soil microbial biomass and activity during the growing season. Soils from lower elevation plots, which accumulated less snow and experienced more soil temperature variability during the winter (and likely more freeze/thaw events), had less extractable inorganic nitrogen (N), lower rates of microbial N production via potential net N mineralization and nitrification, and higher potential microbial respiration during the growing season. Potential nitrate production rates during the growing season were particularly sensitive to changes in winter snow pack accumulation and winter soil temperature variability, especially in spring. Effects of elevation and winter conditions on N transformation rates differed from those on potential microbial respiration, suggesting that N-related processes might respond differently to winter climate change in northern hardwood forests than C-related processes. © 2014 John Wiley & Sons Ltd.

  2. Growing season carries stronger contributions to albedo dynamics on the Tibetan plateau.

    Science.gov (United States)

    Tian, Li; Chen, Jiquan; Zhang, Yangjian

    2017-01-01

    The Tibetan Plateau has experienced higher-than-global-average climate warming in recent decades, resulting in many significant changes in ecosystem structure and function. Among them is albedo, which bridges the causes and consequences of land surface processes and climate. The plateau is covered by snow/ice and vegetation in the non-growing season (nGS) and growing season (GS), respectively. Based on the MODIS products, we investigated snow/ice cover and vegetation greenness in relation to the spatiotemporal changes of albedo on the Tibetan Plateau from 2000 through 2013. A synchronous relationship was found between the change in GSNDVI and GSalbedo over time and across the Tibetan landscapes. We found that the annual average albedo had a decreasing trend, but that the albedo had slightly increased during the nGS and decreased during the GS. Across the landscapes, the nGSalbedo fluctuated in a synchronous pattern with snow/ice cover. Temporally, monthly snow/ice coverage also had a high correspondence with albedo, except in April and October. We detected clear dependencies of albedo on elevation. With the rise in altitude, the nGSalbedo decreased below 4000 m, but increased for elevations of 4500-5500 m. Above 5500 m, the nGSalbedo decreased, which was in accordance with the decreased amount of snow/ice coverage and the increased soil moisture on the plateau. More importantly, the decreasing albedo in the most recent decade appeared to be caused primarily by lowered growing season albedo.

  3. Seasonal sap flow of four Salix varieties growing on the Solvay wastebeds in Syracuse, NY, USA.

    Science.gov (United States)

    Mirck, Jaconette; Volk, Timothy A

    2010-01-01

    Sap flow of four shrub willow varieties was measured to study their potential use as an evapotranspiration (ET) cover on the Solvay wastebeds to reduce deep percolation and leaching of chloride. Stem and stand-level sap flow and crop coefficients (K(c)) were different among four willow varieties measured between early June and mid November 2006. Diameter and cross sectional area had a significant impact on stand level sap flow. Peak stand-level sap flow of 7 mm d(-1) occurred in June, due to coupling of the willow with the atmosphere, and not in July or August when peak LAI was measured. The coupling also resulted in high K(c) values of 3 in June and above 2 in October with an average of 1.1-1.3 for the entire season. Our measurements confirmed the potentials of shrub willow in ET cover applications in the northeastern USA. Total transpiration for the growing season ranged between 494 mm and 533 mm, which was about 45% of the precipitation in 2006. Our calculations showed a significant difference between peak season sap flow in June, July and August and sap flow over the course of the whole growing season, which showed the need for long-term measurements.

  4. Changing water availability during the African maize-growing season, 1979-2010

    Science.gov (United States)

    Estes, Lyndon D.; Chaney, Nathaniel W.; Herrera-Estrada, Julio; Sheffield, Justin; Caylor, Kelly K.; Wood, Eric F.

    2014-07-01

    Understanding how global change is impacting African agriculture requires a full physical accounting of water supply and demand, but accurate, gridded data on key drivers (e.g., humidity) are generally unavailable. We used a new bias-corrected meteorological dataset to analyze changes in precipitation (supply), potential evapotranspiration ({{E}_{p}}, demand), and water availability (expressed as the ratio P/{{E}_{p}}) in 20 countries (focusing on their maize-growing regions and seasons), between 1979 and 2010, and the factors driving changes in {{E}_{p}}. Maize-growing areas in Southern Africa, particularly South Africa, benefitted from increased water availability due in large part to demand declines driven primarily by declining net radiation, increasing vapor pressure, and falling temperatures (with no effect from changing windspeed), with smaller increases in supply. Sahelian zone countries in West Africa, as well as Ethiopia in East Africa, had strong increases in availability driven primarily by rainfall rebounding from the long-term Sahelian droughts, with little change or small reductions in demand. However, intra-seasonal supply variability generally increased in West and East Africa. Across all three regions, declining net radiation contributed downwards pressure on demand, generally over-riding upwards pressure caused by increasing temperatures, the regional effects of which were largest in East Africa. A small number of countries, mostly in or near East Africa (Tanzania and Malawi) experienced declines in water availability primarily due to decreased rainfall, but exacerbated by increasing demand. Much of the reduced water availability in East Africa occurred during the more sensitive middle part of the maize-growing season, suggesting negative consequences for maize production.

  5. Changes in Growing Season Vegetation and Their Associated Driving Forces in China during 2001–2012

    Directory of Open Access Journals (Sweden)

    Xianfeng Liu

    2015-11-01

    Full Text Available In recent decades, the monitoring of vegetation dynamics has become crucial because of its important role in terrestrial ecosystems. In this study, a satellite-derived normalized difference vegetation index (NDVI was combined with climate factors to explore the spatiotemporal patterns of vegetation change during the growing season, as well as their driving forces in China from 2001 to 2012. Our results showed that the growing season NDVI increased continuously during 2001–2012, with a linear trend of 1.4%/10 years (p < 0.01. The NDVI in north China mainly exhibited an increasing spatial trend, but this trend was generally decreasing in south China. The vegetation dynamics were mainly at a moderate intensity level in both the increasing and decreasing areas. The significantly increasing trend in the NDVI for arid and semi-arid areas of northwest China was attributed mainly to an increasing trend in the NDVI during the spring, whereas that for the north and northeast of China was due to an increasing trend in the NDVI during the summer and autumn. Different vegetation types exhibited great variation in their trends, where the grass-forb community had the highest linear trend of 2%/10 years (p < 0.05, followed by meadow, and needle-leaf forest with the lowest increasing trend, i.e., a linear trend of 0.3%/10 years. Our results also suggested that the cumulative precipitation during the growing season had a dominant effect on the vegetation dynamics compared with temperature for all six vegetation types. In addition, the response of different vegetation types to climate variability exhibited considerable differences. In terms of anthropological activity, our statistical analyses showed that there was a strong correlation between the cumulative afforestation area and NDVI during the study period, especially in a pilot region for ecological restoration, thereby suggesting the important role of ecological restoration programs in ecological recovery

  6. Growing season carries stronger contributions to albedo dynamics on the Tibetan plateau.

    Directory of Open Access Journals (Sweden)

    Li Tian

    Full Text Available The Tibetan Plateau has experienced higher-than-global-average climate warming in recent decades, resulting in many significant changes in ecosystem structure and function. Among them is albedo, which bridges the causes and consequences of land surface processes and climate. The plateau is covered by snow/ice and vegetation in the non-growing season (nGS and growing season (GS, respectively. Based on the MODIS products, we investigated snow/ice cover and vegetation greenness in relation to the spatiotemporal changes of albedo on the Tibetan Plateau from 2000 through 2013. A synchronous relationship was found between the change in GSNDVI and GSalbedo over time and across the Tibetan landscapes. We found that the annual average albedo had a decreasing trend, but that the albedo had slightly increased during the nGS and decreased during the GS. Across the landscapes, the nGSalbedo fluctuated in a synchronous pattern with snow/ice cover. Temporally, monthly snow/ice coverage also had a high correspondence with albedo, except in April and October. We detected clear dependencies of albedo on elevation. With the rise in altitude, the nGSalbedo decreased below 4000 m, but increased for elevations of 4500-5500 m. Above 5500 m, the nGSalbedo decreased, which was in accordance with the decreased amount of snow/ice coverage and the increased soil moisture on the plateau. More importantly, the decreasing albedo in the most recent decade appeared to be caused primarily by lowered growing season albedo.

  7. Complex interaction between genotypes and growing seasons of carioca common bean in Goiás/Distrito Federal

    Directory of Open Access Journals (Sweden)

    Helton Santos Pereira

    2011-01-01

    Full Text Available The objectives of this study were to assess the importance of the complex interaction between common beangenotypes and growing seasons in the state of Goiás and the Distrito Federal and verify the need for evaluation and indication ofcultivars for each season. Yield data of 16 genotypes in 16 trials conducted in two growing seasons (winter and rainy were used. Thecoefficient of determination was estimated in the analyses of variance with decomposition of the genotype x environment interaction.The complex percentage of the interaction was estimated and the Spearman correlation between seasons. Differences were detectedbetween seasons and presence of genotype - season (GS interaction, with greater significance than the other double interactionswith genotypes. The correlations indicated a predominantly complex GS interaction. This predominantly complex nature of the GSinteraction calls for an assessment of the genotypes in both seasons, which may however identify cultivars with general adaptation.

  8. Impact of Growing-Season Meteorology on Japonica Rice Productivity in Northeastern China

    Science.gov (United States)

    Yu, W.; Zhang, Y. E.; Wang, Y.; Liu, J. J.; Chen, W.; Seng, S. S.; Zhuang, J. Y.; Gao, L. W.; Ahmed, A.-G.; Li, Z. M.; Li, G. Q.; Xu, S. W.

    2017-10-01

    Meteorological factors have major impact on crop productivity in the world. Many researchers have evaluated the possible impact of climate change on crop yields using models. Here we use a 1980–2015panel dataset from China Agricultural Cost and Return Yearbook to investigate the meteorological impact on Chinese Japonica rice yield growth. We find that average temperature has significantly positive effect on rice yields; while maximum temperature and minimum temperature have negative effect on rice yield. Physicalinputs and time trend (technological progress) into the crop yield have an accurate estimation on crop yields. Means including irrigation or drainage could use during growing season.

  9. Efficiency of nitrogen fertilizer applied at corn sowing in contrasting growing seasons in Paraguay

    Directory of Open Access Journals (Sweden)

    Telmo Jorge Carneiro Amado

    2013-12-01

    Full Text Available In order to select soil management practices that increase the nitrogen-use efficiency (NUE in agro-ecosystems, the different indices of agronomic fertilizer efficiency must be evaluated under varied weather conditions. This study assessed the NUE indices in no-till corn in southern Paraguay. Nitrogen fertilizer rates from 0 to 180 kg ha-1 were applied in a single application at corn sowing and the crop response investigated in two growing seasons (2010 and 2011. The experimental design was a randomized block with three replications. Based on the data of grain yield, dry matter, and N uptake, the following fertilizer indices were assessed: agronomic N-use efficiency (ANE, apparent N recovery efficiency (NRE, N physiological efficiency (NPE, partial factor productivity (PFP, and partial nutrient balance (PNB. The weather conditions varied largely during the experimental period; the rainfall distribution was favorable for crop growth in the first season and unfavorable in the second. The PFP and ANE indices, as expected, decreased with increasing N fertilizer rates. A general analysis of the N fertilizer indices in the first season showed that the maximum rate (180 kg ha-1 obtained the highest corn yield and also optimized the efficiency of NPE, NRE and ANE. In the second season, under water stress, the most efficient N fertilizer rate (60 kg ha-1 was three times lower than in the first season, indicating a strong influence of weather conditions on NUE. Considering that weather instability is typical for southern Paraguay, anticipated full N fertilization at corn sowing is not recommended due the temporal variability of the optimum N fertilizer rate needed to achieve high ANE.

  10. Season of testing and its effect on feed intake and efficiency in growing beef cattle.

    Science.gov (United States)

    Mujibi, F D N; Moore, S S; Nkrumah, D J; Wang, Z; Basarab, J A

    2010-12-01

    This study sought to assess whether residual feed intake (RFI) calculated by regressing feed intake (DMI) on growth rate (ADG) and metabolic mid-BW in 3 different ways led to similar estimates of genetic parameters and variance components for young growing cattle tested for feed intake in fall and winter seasons. A total of 378 beef steers in 5 cohorts were fed a typical high energy feedlot diet and had free-choice access to feed and water. Feed intake data were collected in fall or winter seasons. Climate data were obtained from the University of Alberta Kinsella meteorological station and Vikings AGCM station. Individual animal RFI was obtained by either fitting a regression model to each test group separately (RFI(C)), fitting a regression model to pooled data consisting of all cohorts but including test group as a fixed effect (RFI(O)), or fitting a regression to pooled data with test group as a fixed effect but within seasonal (fall-winter or winter-spring) groups (RFI(S)). Two animal models (M1 and M2) that differed by the inclusion of fixed effects of test group or season, respectively, were used to evaluate RFI measurements. Feed intake was correlated with air temperature, relative humidity, solar radiation, and wind speed (-0.26, 0.23, 0.30, -0.14 for fall-winter and 0.31, -0.04, 0.14, 0.16 for winter-spring, respectively), but the nature and magnitude of the correlations were different for the 2 seasons. Single trait direct heritability, model likelihood, direct genetic variance, and EBV accuracy estimates were greatest for RFI(C) and least for RFI(O) for both M1 and M2 models. A significant genetic correlation was also observed between RFI(O) and ADG, but not for RFI(C) and RFI(S). Including a season effect (M2) in the genetic evaluation of RFI(O) resulted in the smallest heritability, model LogL, EBV accuracy, and largest residual variance estimates. These results, though not conclusive, suggest a possible effect of seasonality on feed intake and thus

  11. Growing season net ecosystem CO2 exchange of two desert ecosystems with alkaline soils in Kazakhstan

    Science.gov (United States)

    Li, Longhui; Chen, Xi; van der Tol, Christiaan; Luo, Geping; Su, Zhongbo

    2014-01-01

    Central Asia is covered by vast desert ecosystems, and the majority of these ecosystems have alkaline soils. Their contribution to global net ecosystem CO2 exchange (NEE) is of significance simply because of their immense spatial extent. Some of the latest research reported considerable abiotic CO2 absorption by alkaline soil, but the rate of CO2 absorption has been questioned by peer communities. To investigate the issue of carbon cycle in Central Asian desert ecosystems with alkaline soils, we have measured the NEE using eddy covariance (EC) method at two alkaline sites during growing season in Kazakhstan. The diurnal course of mean monthly NEE followed a clear sinusoidal pattern during growing season at both sites. Both sites showed significant net carbon uptake during daytime on sunny days with high photosynthetically active radiation (PAR) but net carbon loss at nighttime and on cloudy and rainy days. NEE has strong dependency on PAR and the response of NEE to precipitation resulted in an initial and significant carbon release to the atmosphere, similar to other ecosystems. These findings indicate that biotic processes dominated the carbon processes, and the contribution of abiotic carbon process to net ecosystem CO2 exchange may be trivial in alkaline soil desert ecosystems over Central Asia. PMID:24455157

  12. Growing season carbon dioxide exchange in flooded non-mulching and non-flooded mulching cotton.

    Directory of Open Access Journals (Sweden)

    Zhi-guo Li

    Full Text Available There is much interest in the role that agricultural practices might play in sequestering carbon to help offset rising atmospheric CO₂ concentrations. However, limited information exists regarding the potential for increased carbon sequestration of different management strategies. The objective of this study was to quantify and contrast carbon dioxide exchange in traditional non-mulching with flooding irrigation (TF and plastic film mulching with drip irrigation (PM cotton (Gossypium hirsutum L. fields in northwest China. Net primary productivity (NPP, soil heterotrophic respiration (R(h and net ecosystem productivity (NEP were measured during the growing seasons in 2009 and 2010. As compared with TF, PM significantly increased the aboveground and belowground biomass and the NPP (340 g C m⁻² season⁻¹ of cotton, and decreased the R(h (89 g C m⁻² season⁻¹ (p<0.05. In a growing season, PM had a higher carbon sequestration in terms of NEP of ∼ 429 g C m⁻² season⁻¹ than the TF. These results demonstrate that conversion of this type of land use to mulching practices is an effective way to increase carbon sequestration in the short term in cotton systems of arid areas.

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

    Science.gov (United States)

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

    2001-11-01

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

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

    Science.gov (United States)

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

    2001-01-01

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

  15. Long-term variations in phenological phases and growing season indexes in the Czech Republic

    Science.gov (United States)

    Mozny, M.; Potop, V.; Hajkova, L.; Bares, D.; Stalmacher, M.; Trnka, M.; Bartosova, L.; Zalud, Z.

    2012-04-01

    Phenological phases reflect weather conditions immediately prior to their onset and are therefore very important documentary record of the impact of climate on plants in a particular region. We analyze the results of phenological observations in the Czech Republic in the years 1931-2010. Air temperature increases were associated with an earlier onset of phenological phases; not just the beginning of the growing season but also the interval between successive phenological phases was shorter. Spatial variability of average phenophase onset were executed by GIS methods, the maps use horizontal resolutions of 500 meters. To quantify the rate and timing of changes in canopy development was utilized Growing Season Index (GSI), which was calculated from conventional meteorological measurements. Finally, we used the GSI index for producing global maps that distinguish regional differences in the current phenological development in the Czech Republic. GSI index can be used in modeling of CO2 exchange at the interface of biosphere and atmosphere. We gratefully acknowledge the support of the Ministry of education, youth and sports project OC10010, LD11401 and National Agency for Agriculture Research project Q191C054.

  16. Topoclimate effects on growing season length and montane conifer growth in complex terrain

    Science.gov (United States)

    Barnard, D. M.; Barnard, H. R.; Molotch, N. P.

    2017-05-01

    Spatial variability in the topoclimate-driven linkage between forest phenology and tree growth in complex terrain is poorly understood, limiting our understanding of how ecosystems function as a whole. To characterize the influence of topoclimate on phenology and growth, we determined the start, end, and length of the growing season (GSstart, GSend, and GSL, respectively) using the correlation between transpiration and evaporative demand, measured with sapflow. We then compared these metrics with stem relative basal area increment (relative BAI) at seven sites among elevation and aspects in a Colorado montane forest. As elevation increased, we found shorter GSL (-50 d km-1) due to later GSstart (40 d km-1) and earlier GSend (-10 d km-1). North-facing sites had a 21 d shorter GSL than south-facing sites at similar elevations (i.e. equal to 200 m elevation difference on a given aspect). Growing season length was positively correlated with relative BAI, explaining 83% of the variance. This study shows that topography exerts strong environmental controls on GSL and thus forest growth. Given the climate-related dependencies of these controls, the results presented here have important implications for ecosystem responses to changes in climate and highlight the need for improved phenology representation in complex terrain.

  17. Growing season length as a key factor of cumulative net ecosystem exchange over the pine forest ecosystems in Europe

    Czech Academy of Sciences Publication Activity Database

    Danielewska, A.; Urbaniak, M.; Olejnik, Janusz

    2015-01-01

    Roč. 29, č. 2 (2015), s. 129-135 ISSN 0236-8722 Institutional support: RVO:67179843 Keywords : forest * carbon dioxide * eddy covariance * growing season length Subject RIV: EH - Ecology, Behaviour Impact factor: 1.067, year: 2015

  18. Freezing resistance varies within the growing season and with elevation in high-Andean species of central Chile.

    Science.gov (United States)

    Sierra-Almeida, Angela; Cavieres, Lohengrin A; Bravo, León A

    2009-01-01

    Predicted increases in the length of the growing season as a result of climate change may more frequently expose high-elevation plants to severe frosts. Understanding the ability of these species to resist frosts during the growing season is essential for predicting how species may respond to changes in temperature regimes. Here, we assessed the freezing resistance of 24 species from the central Chilean Andes by determining their low temperature damage (LT(50)), ice nucleation temperature (NT), freezing point (FP) and freezing resistance mechanism (i.e. avoidance or tolerance). The Andean species were found to resist frosts from -8.2 to -19.5 degrees C during the growing season, and freezing tolerance was the most common resistance mechanism. Freezing resistance (LT(50)) varied within the growing season, decreasing towards the end of this period in most of the studied species. However, the FP showed the opposite trend. LT(50) increased with elevation, whilst FP was lower in plants from lower elevations, especially late in the growing season. Andean species have the potential to withstand severe freezing conditions during the growing season, and the aridity of this high-elevation environment seems to play an important role in determining this high freezing resistance.

  19. The impact of changing climate conditions on the hydrological behavior of several Mediterranean sub-catchments in Crete

    Science.gov (United States)

    Eirini Vozinaki, Anthi; Tapoglou, Evdokia; Tsanis, Ioannis

    2017-04-01

    Climate change, although is already happening, consists of a big threat capable of causing lots of inconveniences in future societies and their economies. In this work, the climate change impact on the hydrological behavior of several Mediterranean sub-catchments, in Crete, is presented. The sensitivity of these hydrological systems to several climate change scenarios is also provided. The HBV hydrological model has been used, calibrated and validated for the study sub-catchments against measured weather and streamflow data and inputs. The impact of climate change on several hydro-meteorological parameters (i.e. precipitation, streamflow etc.) and hydrological signatures (i.e. spring flood peak, length and volume, base flow, flow duration curves, seasonality etc.) have been statistically elaborated and analyzed, defining areas of increased probability risk associated additionally to flooding or drought. The potential impacts of climate change on current and future water resources have been quantified by driving HBV model with current and future scenarios, respectively, for specific climate periods. This work aims to present an integrated methodology for the definition of future climate and hydrological risks and the prediction of future water resources behavior. Future water resources management could be rationally effectuated, in Mediterranean sub-catchments prone to drought or flooding, using the proposed methodology. The research reported in this paper was fully supported by the Project "Innovative solutions to climate change adaptation and governance in the water management of the Region of Crete - AQUAMAN" funded within the framework of the EEA Financial Mechanism 2009-2014.

  20. Forest phenology and a warmer climate - Growing season extension in relation to climatic provenance

    Energy Technology Data Exchange (ETDEWEB)

    Gunderson, Carla A [ORNL; Edwards, Nelson T [ORNL; Walker, Ashley V [ORNL; O' Hara, Keiran H [ORNL; Campion, Christina M [ORNL; Hanson, Paul J [ORNL

    2012-01-01

    Predicting forest responses to warming climates relies on assumptions about niche and temperature sensitivity that remain largely untested. Observational studies have related current and historical temperatures to phenological shifts, but experimental evidence is sparse, particularly for autumn responses. A five-year field experiment exposed four deciduous forest species from contrasting climates (Liquidambar styraciflua, Quercus rubra, Populus grandidentata, and Betula alleghaniensis) to air temperatures 2 and 4 C above ambient controls. Impacts of year-round warming on bud burst (BB), senescence and abscission were evaluated in relation to thermal provenance. Leaves emerged earlier in all species, by an average of 6-9 days at +2 and +4 C. Magnitude of advance varied with species and year, but was larger for the first 2 C increment than the second. The effect of warming increased with early BB, favoring Liquidambar, from the warmest climate, but even BB in northern species advanced, despite temperatures well beyond those of the realized niche. Treatment differences in BB were poorly explained by temperature sums, which increased with treatment. In autumn, chlorophyll was retained an average of 4 and 7 days longer in +2 and +4 C treatments, and abscission delayed by 8 and 13 days. Species differences in autumn responses were marginally significant. Growing seasons in the warmer atmospheres were 6 - 28 days longer, with the least impact in Quercus. Results are compared with a 16-year record of canopy onset and offset in a nearby upland deciduous forest, where BB showed similar responsiveness to spring temperatures (2 - 4 days C-1). Offset dates in the stand tracked August-September temperatures, except when late summer drought caused premature senescence. The common garden-like experimental approach provides evidence that warming alone extends the growing season, at both ends, even if stand-level impacts are complicated by other environmental factors.

  1. Effects of urban green infrastructure (UGI) on local outdoor microclimate during the growing season.

    Science.gov (United States)

    Wang, Yafei; Bakker, Frank; de Groot, Rudolf; Wörtche, Heinrich; Leemans, Rik

    2015-12-01

    This study analyzed how the variations of plant area index (PAI) and weather conditions alter the influence of urban green infrastructure (UGI) on microclimate. To observe how diverse UGIs affect the ambient microclimate through the seasons, microclimatic data were measured during the growing season at five sites in a local urban area in The Netherlands. Site A was located in an open space; sites B, C, and D were covered by different types and configurations of green infrastructure (grove, a single deciduous tree, and street trees, respectively); and site E was adjacent to buildings to study the effects of their façades on microclimate. Hemispherical photography and globe thermometers were used to quantify PAI and thermal comfort at both shaded and unshaded locations. The results showed that groves with high tree density (site B) have the strongest effect on microclimate conditions. Monthly variations in the differences of mean radiant temperature (∆Tmrt) between shaded and unshaded areas followed the same pattern as the PAI. Linear regression showed a significant positive correlation between PAI and ∆Tmrt. The difference of daily average air temperature (∆T a ) between shaded and unshaded areas was also positively correlated to PAI, but with a slope coefficient below the measurement accuracy (±0.5 °C). This study showed that weather conditions can significantly impact the effectiveness of UGI in regulating microclimate. The results of this study can support the development of appropriate UGI measures to enhance thermal comfort in urban areas.

  2. Trends in temperature and growing season length in idaho-usa during the past few decades

    Directory of Open Access Journals (Sweden)

    Carlos Antonio Costa dos Santos

    2015-12-01

    Full Text Available ABSTRACT This study attempts to provide new information on seasonal and annual trends, on a regional scale, using records of daily air temperature over Idaho, USA, through the analysis of the Growing Season Length (GSL, and maximum and minimum air temperature data from multiple stations in the region, as well as, to obtain the temporal correlation between the daily air temperature and Sea Surface Temperature (SST indices. The analyses were conducted using long-term and high quality data sets for 35 meteorological stations for the period between 1970 and 2006. The results suggest that both daily maximum and minimum temperatures had increasing trends, but the minimum air temperature is increasing faster than the maximum air temperature. On average, the GSL has increased by 7.5 days/decade during the period 1970-2006, associated with increasing temperatures. Trends in regional air temperature and their indication of climate change are of interest to Idaho and the rest of the world. The trends obtained herein corroborate with the general idea that during the last century the globe has warmed.

  3. Pan-Arctic linkages between snow accumulation and growing-season air temperature, soil moisture and vegetation

    Science.gov (United States)

    Luus, K. A.; Gel, Y.; Lin, J. C.; Kelly, R. E. J.; Duguay, C. R.

    2013-11-01

    Arctic field studies have indicated that the air temperature, soil moisture and vegetation at a site influence the quantity of snow accumulated, and that snow accumulation can alter growing-season soil moisture and vegetation. Climate change is predicted to bring about warmer air temperatures, greater snow accumulation and northward movements of the shrub and tree lines. Understanding the responses of northern environments to changes in snow and growing-season land surface characteristics requires: (1) insights into the present-day linkages between snow and growing-season land surface characteristics; and (2) the ability to continue to monitor these associations over time across the vast pan-Arctic. The objective of this study was therefore to examine the pan-Arctic (north of 60° N) linkages between two temporally distinct data products created from AMSR-E satellite passive microwave observations: GlobSnow snow water equivalent (SWE), and NTSG growing-season AMSR-E Land Parameters (air temperature, soil moisture and vegetation transmissivity). Due to the complex and interconnected nature of processes determining snow and growing-season land surface characteristics, these associations were analyzed using the modern nonparametric technique of alternating conditional expectations (ACE), as this approach does not impose a predefined analytic form. Findings indicate that regions with lower vegetation transmissivity (more biomass) at the start and end of the growing season tend to accumulate less snow at the start and end of the snow season, possibly due to interception and sublimation. Warmer air temperatures at the start and end of the growing season were associated with diminished snow accumulation at the start and end of the snow season. High latitude sites with warmer mean annual growing-season temperatures tended to accumulate more snow, probably due to the greater availability of water vapor for snow season precipitation at warmer locations. Regions with drier

  4. Pan-Arctic linkages between snow accumulation and growing-season air temperature, soil moisture and vegetation

    Directory of Open Access Journals (Sweden)

    K. A. Luus

    2013-11-01

    Full Text Available Arctic field studies have indicated that the air temperature, soil moisture and vegetation at a site influence the quantity of snow accumulated, and that snow accumulation can alter growing-season soil moisture and vegetation. Climate change is predicted to bring about warmer air temperatures, greater snow accumulation and northward movements of the shrub and tree lines. Understanding the responses of northern environments to changes in snow and growing-season land surface characteristics requires: (1 insights into the present-day linkages between snow and growing-season land surface characteristics; and (2 the ability to continue to monitor these associations over time across the vast pan-Arctic. The objective of this study was therefore to examine the pan-Arctic (north of 60° N linkages between two temporally distinct data products created from AMSR-E satellite passive microwave observations: GlobSnow snow water equivalent (SWE, and NTSG growing-season AMSR-E Land Parameters (air temperature, soil moisture and vegetation transmissivity. Due to the complex and interconnected nature of processes determining snow and growing-season land surface characteristics, these associations were analyzed using the modern nonparametric technique of alternating conditional expectations (ACE, as this approach does not impose a predefined analytic form. Findings indicate that regions with lower vegetation transmissivity (more biomass at the start and end of the growing season tend to accumulate less snow at the start and end of the snow season, possibly due to interception and sublimation. Warmer air temperatures at the start and end of the growing season were associated with diminished snow accumulation at the start and end of the snow season. High latitude sites with warmer mean annual growing-season temperatures tended to accumulate more snow, probably due to the greater availability of water vapor for snow season precipitation at warmer locations. Regions

  5. Carbonyl Sulfide Fluxes from a Tall Grass Prairie Ecosystem Through a Growing Season

    Science.gov (United States)

    Alsip, B. M.; Berkelhammer, M. B.; Matamala, R.; Cook, D. R.; Whelan, C.

    2016-12-01

    An ecosystem's carbonyl sulfide (OCS or COS) flux is a powerful proxy for plant-controlled carbon and water exchange. Few studies have applied this approach to grassland ecosystems, which are characterized by complex species distributions that vary temporally. Our results reported here contrast previous work done on OCS fluxes from agricultural and forest ecosystems where climate and phenology shift but species distributions are fixed. A laser absorption spectrometer installed in a temperature-controlled enclosure measured OCS flux data continuously during the entire growing season at the Fermi prairie eddy covariance site in Illinois, USA. Ambient atmospheric concentrations of OCS, carbon monoxide, carbon dioxide (CO2), and water vapor (H2O) were sampled at 1 Hz frequency from four inlets at different heights within and above the vegetation canopy from May to October, 2016. We observed a well-defined seasonal OCS cycle whose trend followed the Northern Hemisphere average. The data also show a strong diel cycle in the above-canopy gradient and absolute concentrations. Nighttime OCS in the canopy periodically dropped below 30 pmol•m-1, which, to our knowledge, are the lowest tropospheric OCS concentrations ever observed. These values were associated with steep OCS gradients above the canopy of -80 pmol•mol-1•m-1. These results highlight significant nighttime plant and soil uptake of OCS. Midday OCS gradients were -8.0 pmol•mol-1•m-1 and variations followed the day-to-day CO2 gradient. This demonstrates the close coupling of OCS and CO2 even as the season and species makeup evolves. Using the flux-gradient approach, we will convert OCS gradients to ecosystem fluxes by deriving the eddy diffusivity from existing eddy covariance data on site. After correcting for OCS and CO2 soil fluxes, we will compare gross primary productivity (GPP) derived from the two approaches, and assess the robustness of OCS to constrain GPP in this ecosystem.

  6. Growing degree-days for the `Niagara Rosada' grapevine pruned in different seasons

    Science.gov (United States)

    Scarpare, Fábio Vale; Scarpare Filho, João Alexio; Rodrigues, Alessandro; Reichardt, Klaus; Angelocci, Luiz Roberto

    2012-09-01

    Plant growth and development are proportional to biological time, or the thermal time of the species, which can be defined as the integral of the temperature over time between the lower and upper temperature developmental thresholds. The objective of this study was to investigate the efficiency of the growing degree-day (GDD) approach for vines of the `Niagara Rosada' cultivar pruned in winter and summer seasons, and physiological phases (mobilisation and reserve accumulation) in a humid subtropical region. The experiment was carried out on 13-year-old plants in Piracicaba, São Paulo State-Brazil, evaluating 24 production cycles, 12 from the winter pruning, and 12 from the summer pruning. The statistical design was comprised of randomised blocks, using the pruning dates as treatment: 20 July, 4 August, 19 August, and 3 September (winter); 1 February, 15 February, 2 March, and 16 March (summer). Comparison of the mean values of GDD among pruning dates was evaluated by the Tukey test, and comparison between pruning seasons was made by the F test for orthogonal contrasts, both at the 5% probability level. The results showed good agreement between the values of GDD required to complete the cycle from the winter pruning until harvest when compared with other studies performed with the same cultivar grown in the Southern and Southeastern regions of Brazil. However, there was a consistent statistical difference between GDD computed for winter and summer pruning, which allowed us to conclude that this bio-meteorological index is not sufficient to distinguish vines pruned in different seasons and physiological phases applied in humid subtropical climates.

  7. Growing degree-days for the 'Niagara Rosada' grapevine pruned in different seasons.

    Science.gov (United States)

    Scarpare, Fábio Vale; Scarpare Filho, João Alexio; Rodrigues, Alessandro; Reichardt, Klaus; Angelocci, Luiz Roberto

    2012-09-01

    Plant growth and development are proportional to biological time, or the thermal time of the species, which can be defined as the integral of the temperature over time between the lower and upper temperature developmental thresholds. The objective of this study was to investigate the efficiency of the growing degree-day (GDD) approach for vines of the 'Niagara Rosada' cultivar pruned in winter and summer seasons, and physiological phases (mobilisation and reserve accumulation) in a humid subtropical region. The experiment was carried out on 13-year-old plants in Piracicaba, São Paulo State-Brazil, evaluating 24 production cycles, 12 from the winter pruning, and 12 from the summer pruning. The statistical design was comprised of randomised blocks, using the pruning dates as treatment: 20 July, 4 August, 19 August, and 3 September (winter); 1 February, 15 February, 2 March, and 16 March (summer). Comparison of the mean values of GDD among pruning dates was evaluated by the Tukey test, and comparison between pruning seasons was made by the F test for orthogonal contrasts, both at the 5% probability level. The results showed good agreement between the values of GDD required to complete the cycle from the winter pruning until harvest when compared with other studies performed with the same cultivar grown in the Southern and Southeastern regions of Brazil. However, there was a consistent statistical difference between GDD computed for winter and summer pruning, which allowed us to conclude that this bio-meteorological index is not sufficient to distinguish vines pruned in different seasons and physiological phases applied in humid subtropical climates.

  8. Growing season methane emissions from a permafrost peatland of northeast China: Observations using open-path eddy covariance method

    Science.gov (United States)

    Yu, Xueyang; Song, Changchun; Sun, Li; Wang, Xianwei; Shi, Fuxi; Cui, Qian; Tan, Wenwen

    2017-03-01

    The mid-high latitude permafrost peatlands in the Northern Hemisphere is a major natural source of methane (CH4) to the atmosphere. Ecosystem scale CH4 emissions from a typical permafrost peatland in the Great Hing'an Mountains were observed during the growing season of 2014 and 2015 using the open-path eddy covariance method. Relevant environmental factors such as temperature and precipitation were also collected. There was a clear diurnal variation in methane emissions in the second half of each growing season, with significantly higher emission rates in the wet sector of study area. The daily CH4 exchange ranged from 1.8 mg CH4 m-2 d-1 to 40.2 mg CH4 m-2 d-1 in 2014 and ranged from -3.9 to 15.0 mg CH4 m-2 d-1 in 2015. There were no peaks of CH4 fluxes during the spring thawing period. However, large peaks of CH4 emission were found in the second half of both growing seasons. The CH4 emission after Jul 25th accounted for 77.9% of total growing season emission in 2014 and 85.9% in 2015. The total CH4 emission during the growing season of 2014 and 2015 was approximately 1.52 g CH4 m-2 and 0.71 g CH4 m-2, respectively. CH4 fluxes during the growing seasons were significantly correlated with thawing depth (R2 = 0.71, P emissions in permafrost peatlands. Our multiyear observations indicate that the time-lagged volume of precipitation during the growing season is a key factor in interpreting locally inter-annual variations in CH4 emissions. Our results suggested that the low temperature in the deep soil layers effectively restricts methane production and emission rates; these conditions may create significant positive feedback under global climate change.

  9. Seasonal variations in the community structure of actively growing bacteria in neritic waters of Hiroshima Bay, western Japan.

    Science.gov (United States)

    Taniguchi, Akito; Tada, Yuya; Hamasaki, Koji

    2011-01-01

    Using bromodeoxyuridine (BrdU) magnetic beads immunocapture and a PCR-denaturing gradient gel electrophoresis (DGGE) technique (BUMP-DGGE), we determined seasonal variations in the community structures of actively growing bacteria in the neritic waters of Hiroshima Bay, western Japan. The community structures of actively growing bacteria were separated into two clusters, corresponding to the timing of phytoplankton blooms in the autumn-winter and spring-summer seasons. The trigger for changes in bacterial community structure was related to organic matter supply from phytoplankton blooms. We identified 23 phylotypes of actively growing bacteria, belonging to Alphaproteobacteria (Roseobacter group, 9 phylotypes), Gammaproteobacteria (2 phylotypes), Bacteroidetes (8 phylotypes), and Actinobacteria (4 phylotypes). The Roseobacter group and Bacteroidetes were dominant in actively growing bacterial communities every month, and together accounted for more than 70% of the total DGGE bands. We revealed that community structures of actively growing bacteria shifted markedly in the wake of phytoplankton blooms in the neritic waters of Hiroshima Bay.

  10. Underestimated effects of low temperature during early growing season on carbon sequestration of a subtropical coniferous plantation

    Science.gov (United States)

    Zhang, W.-J.; Wang, H.-M.; Yang, F.-T.; Yi, Y.-H.; Wen, X.-F.; Sun, X.-M.; Yu, G.-R.; Wang, Y.-D.; Ning, J.-C.

    2011-06-01

    The impact of air temperature in early growing season on the carbon sequestration of a subtropical coniferous plantation was discussed through analyzing the eddy flux observations at Qianyanzhou (QYZ) site in southern China from 2003 to 2008. This site experienced two cold early growing seasons (with temperature anomalies of 2-5 °C) in 2005 and 2008, and a severe summer drought in 2003. Results indicated that the low air temperature from January to March was the major factor controlling the inter-annual variations in net carbon uptake at this site, rather than the previously thought summer drought. The accumulative air temperature from January to February showed high correlation (R2=0.970, pplant phenology developing and the growing season length at this subtropical site. The cold spring greatly shortened the growing season length and therefore reduced the carbon uptake period. The eddy flux observations showed a carbon loss of 4.04 g C m-2 per growing-season day at this coniferous forest site. On the other hand, the summer drought also reduced the net carbon uptake strength because the photosynthesis was more sensitive to water deficit stress than the ecosystem respiration. However, the impact of summer drought occurred within a relatively shorter period and the carbon sequestration went back to the normal level once the drought was relieved.

  11. Changes in the thermal growing season in Nordic countries during the past century and prospects for the future

    Directory of Open Access Journals (Sweden)

    T.R. CARTER

    2008-12-01

    Full Text Available The start, end, duration and intensity of the thermal growing season (the period with mean daily temperatures exceeding 5°C during the past century (1890-1995 was analysed at nine sites in the Nordic region. Statistical comparisons were made between three adjacent 35-year periods. The results indicate that the growing season lengthened considerably at all sites between 1891-1925 and 1926-1960. Lengthening has continued at a slower rate up to the present at the eight Fennoscandian sites but not at the Icelandic site. In contrast, the intensity of the growing season, expressed by effective temperature sum above 5°C, which increased at all sites between the first two periods, has decreased slightly at all locations except Turku in recent decades. Under three scenarios, representing the range of estimated greenhouse gas-induced warming by the 2050s, the growing season is expected to lengthen at all sites. For a "Central" scenario, the greatest lengthening is computed for southern and western Scandinavia (7-8 weeks with smaller changes in Finland (4 weeks and Iceland (3 weeks. With a lengthening growing season during the past century in Fennoscandia, there are likely to have been impacts on natural and managed ecosystems. Some evidence of recent biotic and abiotic effects already exists, but other indicators of long-term change remain to be analysed. ;

  12. Global-scale pattern of peatland Sphagnum growth driven by photosynthetically active radiation and growing season length

    Directory of Open Access Journals (Sweden)

    Z. Yu

    2012-07-01

    Full Text Available High-latitude peatlands contain about one third of the world's soil organic carbon, most of which is derived from partly decomposed Sphagnum (peat moss plants. We conducted a meta-analysis based on a global data set of Sphagnum growth measurements collected from published literature to investigate the effects of bioclimatic variables on Sphagnum growth. Analysis of variance and general linear models were used to relate Sphagnum magellanicum and S. fuscum growth rates to photosynthetically active radiation integrated over the growing season (PAR0 and a moisture index. We found that PAR0 was the main predictor of Sphagnum growth for the global data set, and effective moisture was only correlated with moss growth at continental sites. The strong correlation between Sphagnum growth and PAR0 suggests the existence of a global pattern of growth, with slow rates under cool climate and short growing seasons, highlighting the important role of growing season length in explaining peatland biomass production. Large-scale patterns of cloudiness during the growing season might also limit moss growth. Although considerable uncertainty remains over the carbon balance of peatlands under a changing climate, our results suggest that increasing PAR0 as a result of global warming and lengthening growing seasons, without major change in cloudiness, could promote Sphagnum growth. Assuming that production and decomposition have the same sensitivity to temperature, this enhanced growth could lead to greater peat-carbon sequestration, inducing a negative feedback to climate change.

  13. Global-scale pattern of peatland Sphagnum growth driven by photosynthetically active radiation and growing season length

    Science.gov (United States)

    Loisel, J.; Gallego-Sala, A. V.; Yu, Z.

    2012-07-01

    High-latitude peatlands contain about one third of the world's soil organic carbon, most of which is derived from partly decomposed Sphagnum (peat moss) plants. We conducted a meta-analysis based on a global data set of Sphagnum growth measurements collected from published literature to investigate the effects of bioclimatic variables on Sphagnum growth. Analysis of variance and general linear models were used to relate Sphagnum magellanicum and S. fuscum growth rates to photosynthetically active radiation integrated over the growing season (PAR0) and a moisture index. We found that PAR0 was the main predictor of Sphagnum growth for the global data set, and effective moisture was only correlated with moss growth at continental sites. The strong correlation between Sphagnum growth and PAR0 suggests the existence of a global pattern of growth, with slow rates under cool climate and short growing seasons, highlighting the important role of growing season length in explaining peatland biomass production. Large-scale patterns of cloudiness during the growing season might also limit moss growth. Although considerable uncertainty remains over the carbon balance of peatlands under a changing climate, our results suggest that increasing PAR0 as a result of global warming and lengthening growing seasons, without major change in cloudiness, could promote Sphagnum growth. Assuming that production and decomposition have the same sensitivity to temperature, this enhanced growth could lead to greater peat-carbon sequestration, inducing a negative feedback to climate change.

  14. Impact of mulches and growing season on indicator bacteria survival during lettuce cultivation.

    Science.gov (United States)

    Xu, Aixia; Buchanan, Robert L; Micallef, Shirley A

    2016-05-02

    In fresh produce production, the use of mulches as ground cover to retain moisture and control weeds is a common agricultural practice, but the influence that various mulches have on enteric pathogen survival and dispersal is unknown. The goal of this study was to assess the impact of different mulching methods on the survival of soil and epiphytic fecal indicator bacteria on organically grown lettuce during different growing seasons. Organically managed lettuce, cultivated with various ground covers--polyethylene plastic, corn-based biodegradable plastic, paper and straw mulch--and bare ground as a no-mulch control, was overhead inoculated with manure-contaminated water containing known levels of generic Escherichia coli and Enterococcus spp. Leaves and soil samples were collected at intervals over a two week period on days 0, 1, 3, 5, 7, 10 and 14, and quantitatively assessed for E. coli, fecal coliforms and Enterococcus spp. Data were analyzed using mixed models with repeated measures and an exponential decline with asymptote survival model. Indicator bacterial concentrations in the lettuce phyllosphere decreased over time under all treatments, with more rapid E. coli declines in the fall than in the spring (pplastic mulches in all trials, and higher enterococci levels under straw in fall 2014 (p<0.05). This study demonstrates that mulches used in lettuce production may impact the fate of enteric bacteria in soil or on lettuce, most likely in relation to soil moisture retention, and other weather-related factors, such as temperature and rainfall. The data suggest that the time between exposure to a source of enteric bacteria and harvesting of the crop is season dependent, which has implications for determining best harvest times. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Environmental Influences on the Growing Season Duration and Ripening of Diverse Miscanthus Germplasm Grown in Six Countries

    Directory of Open Access Journals (Sweden)

    Christopher Nunn

    2017-05-01

    Full Text Available The development of models to predict yield potential and quality of a Miscanthus crop must consider climatic limitations and the duration of growing season. As a biomass crop, yield and quality are impacted by the timing of plant developmental transitions such as flowering and senescence. Growth models are available for the commercially grown clone Miscanthus x giganteus (Mxg, but breeding programs have been working to expand the germplasm available, including development of interspecies hybrids. The aim of this study was to assess the performance of diverse germplasm beyond the range of environments considered suitable for a Miscanthus crop to be grown. To achieve this, six field sites were planted as part of the EU OPTIMISC project in 2012 in a longitudinal gradient from West to East: Wales—Aberystwyth, Netherlands—Wageningen, Stuttgart—Germany, Ukraine—Potash, Turkey—Adana, and Russia—Moscow. Each field trial contained three replicated plots of the same 15 Miscanthus germplasm types. Through the 2014 growing season, phenotypic traits were measured to determine the timing of developmental stages key to ripening; the tradeoff between growth (yield and quality (biomass ash and moisture content. The hottest site (Adana showed an accelerated growing season, with emergence, flowering and senescence occurring before the other sites. However, the highest yields were produced at Potash, where emergence was delayed by frost and the growing season was shortest. Flowering triggers varied with species and only in Mxg was strongly linked to accumulated thermal time. Our results show that a prolonged growing season is not essential to achieve high yields if climatic conditions are favorable and in regions where the growing season is bordered by frost, delaying harvest can improve quality of the harvested biomass.

  16. Trends in Agricultural Growing Seasons Due to Climatic Shifts in Africa: Implications for Food Security

    Science.gov (United States)

    Brown, M. E.; de Beurs, K.; Vrieling, A.

    2009-12-01

    Some of the most profound and direct impacts of climate change over the next few decades will be on agricultural production and the broader food system. Africa is one of the regions most vulnerable to these impacts due to their under developed economies and the predominance of small farmer, subsistence agriculture. This paper focuses on understanding variations in agricultural production due to rainfall and temperature fluctuations, which are a primary cause of food insecurity on the continent in Africa. A retrospective analysis on the relationship between climate indices and environmental productivity may provide the tools to better manage agricultural investment on the African continent. This paper will present an analysis of the relationship between phenology metrics derived from the 26 year AVHRR NDVI record and the North Atlantic Oscillation index (NAO), the Indian Ocean Dipole (IOD), and the Multivariate ENSO Index (MEI). We explore spatial relationships between agricultural growing conditions as measured by the NDVI and the three climate indices in Eastern, Western and Southern Africa to determine the regions and periods when they have a significant impact. The results show that the start of season and cumulative NDVI were significantly affected by variations in the climate indices. The talk will conclude with analysis which will put these climate-related factors into perspective, as just one element in the overall food security of the region. Agricultural investment policies, the functioning of markets and trade, and an increasing population are at least as important for the food security on the continent. Sustainability of livelihoods will depend both on the ability of vulnerable populations to adapt to changing growing conditions and to compete on the global market for food.

  17. Quantifying the growing season dynamics and phenology of a boreal black spruce wildfire chronosequence: Coupling field measurements with MODIS

    Science.gov (United States)

    Serbin, S. P.; Ahl, D. E.; Gower, S. T.

    2007-12-01

    The boreal forest is the second largest forested biome and the vast area and large carbon stores in the soil makes these forests important to the global carbon, water and energy cycles. Analysis of global coverage, coarse resolution satellite Vegetation Index (VI) data have provided considerable information on the seasonal cycles of vegetation in the mid-to high-latitudes, including the boreal forest, with evidence of an increase in the magnitude of vegetation greenness and a lengthening of the active growing season, which has been attributed to climate warming. However, boreal forests are prone to extensive wildfire disturbance that influence canopy dynamics (i.e. species composition, LAI, and phenology) and separating the direct affect of warming from the indirect affect of increased wildfire frequency on the patterns of boreal phenology and seasonal greeness requires further analysis coupled to ground measurements. In this research we address the need for detailed information on the growing season dynamics and phenological patterns of boreal vegetation. We evaluate whether MODIS reflectance data can resolve small inter-annual variations in canopy phenology and growing season dynamics of boreal forests. We quantified the seasonality and inter-annual differences of the overstory and understory vegetation by optically measuring the LAI and light harvesting potential (FPAR) during the 2004-2006 growing seasons. An automated continuously operating system is used to monitor growing season PAR transmittance. We focused on a boreal wildfire chronosequence of sites comprising a range of forest ages (1-154 years since fire) to quantify the differences in vegetation dynamics and phenology between the deciduous/mixed and coniferous forests. The spatial and temporal characteristics of LAI / FPAR within the chronosequence were examined by comparing both the in situ measurements and the relevant MODIS products. A statistical curve fitting procedure is used to derive the key

  18. Assessment of cereal stand structure and its changes during the growing season

    Directory of Open Access Journals (Sweden)

    Jan Křen

    2012-01-01

    Full Text Available Historical evolution of approaches used for the assessment of the cereal stand structure development is presented. Weaknesses and strengths of these approaches are discussed that are based on: - dividing of cereal yield into yield components and growth analysis, - modular concept of plant growth, - use of laws of plant population biology in order to explain autoregulation and compensation in stands.The presented methods are assessed with respect to labour intensity and possibilities of utilization of obtained information. Other possibilities of diagnostics of the cereal stand state and structure using a current level of knowledge and new technologies enabling to determine spectral characteristics of the stand by areal sensing are outlined. Based on the character of processes influencing the stand structure, the growing season of cereals was divided into the three parts:1. vegetative, including the period from emergence till the end of tillering (BBCH 10-29,2. generative, including the period of stem elongation and heading (BBCH 30-59,3. reproductive, including anthesis, grain formation and maturation (BBCH 60-99.To optimize the stand structure, data necessary for decision making in cereal crop management practices were proposed for the above listed development stages.

  19. Impacts of temperature extremes on European vegetation during the growing season

    Directory of Open Access Journals (Sweden)

    L. Baumbach

    2017-11-01

    Full Text Available Temperature is a key factor controlling plant growth and vitality in the temperate climates of the mid-latitudes like in vast parts of the European continent. Beyond the effect of average conditions, the timings and magnitudes of temperature extremes play a particularly crucial role, which needs to be better understood in the context of projected future rises in the frequency and/or intensity of such events. In this work, we employ event coincidence analysis (ECA to quantify the likelihood of simultaneous occurrences of extremes in daytime land surface temperature anomalies (LSTAD and the normalized difference vegetation index (NDVI. We perform this analysis for entire Europe based upon remote sensing data, differentiating between three periods corresponding to different stages of plant development during the growing season. In addition, we analyze the typical elevation and land cover type of the regions showing significantly large event coincidences rates to identify the most severely affected vegetation types. Our results reveal distinct spatio-temporal impact patterns in terms of extraordinarily large co-occurrence rates between several combinations of temperature and NDVI extremes. Croplands are among the most frequently affected land cover types, while elevation is found to have only a minor effect on the spatial distribution of corresponding extreme weather impacts. These findings provide important insights into the vulnerability of European terrestrial ecosystems to extreme temperature events and demonstrate how event-based statistics like ECA can provide a valuable perspective on environmental nexuses.

  20. Changes in macroelement content in Nuphar lutea (L. Sibith. and Sm. during the growing season

    Directory of Open Access Journals (Sweden)

    Henryk Tomaszewicz

    2011-01-01

    Full Text Available This study presents the results of monitoring studies carried out to determine the chemical composition of Nuphar lutea in two phytocoenoses of Nupharo-Nymphaeetum albae Tomasz. 1977 occurring in two lakes of different trophic types (eutrophic Lake Łaśmiady and oligo-humotrophic Lake Pływające Wyspy. The leaves (collected starting in May, rhizomes and roots of Nuphar lutea as well as water and sediment samples were collected from March to November in the above phytocoenoses (for 3 years in Lake Pływające Wyspy and for 4 years in Lake Łaśmiady. The samples were analysed for several parameters including: phosphate, nitrate, total nitrogen, potassium, sodium, calcium, total iron, sulphate and silica dissolved. In addition the manganese, cadmium, zinc and lead contents were determined in the leaves, rhizomes and roots of the plants collected in July (at the height of the growing season. It was found that the differences in the chemical composition of water and sediments between the lakes studied were more pronounced than in the case of leaves, rhizomes and roots of Nuphar lutea.

  1. Rainfall-derived growing season characteristics for agricultural impact assessments in South Africa

    Science.gov (United States)

    Ambrosino, Chiara; Chandler, Richard E.; Todd, Martin C.

    2014-02-01

    Precipitation variability imposes significant pressure in areas where agricultural practice is dominated by smallholder farmers who are dependent on subsistence farming. Advances in the understanding of this variability, in both time and space, have an important role to play in increasing the resilience of agricultural systems. The need is particularly pressing in regions of the world such as the African continent, which is already affected by multiple stresses including poverty and economic and political instability. In this paper, we explore the use of generalised linear models (GLMs) for this purpose, via a case study from north-east South Africa. A GLM is used to link the local rainfall variability to large-scale climate drivers identified from previous subcontinental-scale analyses, and the ability of the resulting model to simulate precipitation features that are relevant in agricultural applications is evaluated. We focus in particular on a set of growing season indices, proposed for the investigation of intraseasonal characteristics relevant for maize production in the region. Seven indices were computed from spatially averaged daily rainfall series from nine stations in the study area. As a first attempt to use GLMs for this type of application, the results are encouraging and suggest that the models are able to reproduce a range of agriculture-relevant indices. However, further research into spatial correlation structure is recommended to improve the multisite generation of the rainfall-derived characteristics.

  2. Impacts of temperature extremes on European vegetation during the growing season

    Science.gov (United States)

    Baumbach, Lukas; Siegmund, Jonatan F.; Mittermeier, Magdalena; Donner, Reik V.

    2017-11-01

    Temperature is a key factor controlling plant growth and vitality in the temperate climates of the mid-latitudes like in vast parts of the European continent. Beyond the effect of average conditions, the timings and magnitudes of temperature extremes play a particularly crucial role, which needs to be better understood in the context of projected future rises in the frequency and/or intensity of such events. In this work, we employ event coincidence analysis (ECA) to quantify the likelihood of simultaneous occurrences of extremes in daytime land surface temperature anomalies (LSTAD) and the normalized difference vegetation index (NDVI). We perform this analysis for entire Europe based upon remote sensing data, differentiating between three periods corresponding to different stages of plant development during the growing season. In addition, we analyze the typical elevation and land cover type of the regions showing significantly large event coincidences rates to identify the most severely affected vegetation types. Our results reveal distinct spatio-temporal impact patterns in terms of extraordinarily large co-occurrence rates between several combinations of temperature and NDVI extremes. Croplands are among the most frequently affected land cover types, while elevation is found to have only a minor effect on the spatial distribution of corresponding extreme weather impacts. These findings provide important insights into the vulnerability of European terrestrial ecosystems to extreme temperature events and demonstrate how event-based statistics like ECA can provide a valuable perspective on environmental nexuses.

  3. High methane emissions from restored Norway spruce swamps in southern Finland over one growing season

    Directory of Open Access Journals (Sweden)

    M. Koskinen

    2016-02-01

    Full Text Available Forestry-drained peatlands in the boreal region are currently undergoing restoration in order to bring these ecosystems closer to their natural (undrained state. Drainage affects the methane (CH4 dynamics of a peatland, often changing sites from CH4 sources to sinks. Successful restoration of a peatland would include restoration of not only the surface vegetation and hydrology, but also the microbial populations and thus CH4 dynamics. As a pilot study, CH4 emissions were measured on two pristine, two drained and three restored boreal spruce swamps in southern Finland for one growing season. Restoration was successful in the sense that the water table level in the restored sites was significantly higher than in the drained sites, but it was also slightly higher than in the pristine sites. The restored sites were surprisingly large sources of CH4 (mean emissions of 52.84 mg CH4 m-2 d-1, contrasting with both the pristine (1.51 mg CH4 m-2 d-1 and the drained sites (2.09 mg CH4 m-2 d-1. More research is needed to assess whether the high CH4 emissions observed in this study are representative of restored spruce mires in general.

  4. THE INFLUENCE OF WEATHER CONDITIONS OF EASTERN POLAND ON SWEET CORN YIELDS AND LENGTH OF GROWING SEASON

    Directory of Open Access Journals (Sweden)

    Robert Rosa

    2016-09-01

    Full Text Available The aim of the study was to determine the effect of weather components (air temperature, precipitation on the growth, yield and the length of the growing season of sweet corn cultivated in eastern Poland. The results come from a field experiment conducted in 2006–2011. Weather conditions in the successive years of the study significantly modified the yield of ears, weight and number of formatted ears, high of plants and the length of the growing season of sweet corn. Good yielding of sweet corn favoured years with moderate air temperatures in July and uniform distribution of precipitation during the growing season. The highest yield of ears was found in 2011, the lowest in the very difficult in terms of weather 2006. The shortest growing season was characterized corn grown in the years 2006 and 2010 with the high air temperatures in July and August, the longest in the years 2009 and 2011, in which the temperatures in the period June-August were the lowest of all the years of research. Irrespective of the year of study, cv ‘Sheba F1’ was formatted eras with higher weight than cv ‘Sweet Nugget F1’.

  5. n-Alkane biosynthetic hydrogen isotope fractionation is not constant throughout the growing season in the riparian tree Salix viminalis

    Science.gov (United States)

    Newberry, Sarah L.; Kahmen, Ansgar; Dennis, Paul; Grant, Alastair

    2015-09-01

    Compound-specific δ2H values of leaf wax n-alkanes have emerged as a potentially powerful paleohydrological proxy. Research suggests terrestrial plant n-alkane δ2H values are strongly correlated with meteoric water δ2H values, and may provide information on temperature, relative humidity, evaporation, and precipitation. This is based upon several assumptions, including that biosynthetic fractionation of n-alkanes during synthesis is constant within a single species. Here we present a multi-isotope study of the n-alkanes of riparian Salix viminalis growing in Norwich, UK. We measured n-alkane δ2H, leaf water δ2H, xylem water δ2H, and bulk foliar δ13C and evaluated the variability of n-alkane δ2H values and net biosynthetic fractionation (εlw-wax) over a whole growing season. S. viminalis n-alkane δ2H values decreased by 40‰ between the start of the growing season in April and the time when they stabilized in July. Variation in leaf and xylem water δ2H did not explain this variability. εlw-wax varied from -116‰ during leaf expansion in April to -156‰ during the stable phase. This suggests that differential biosynthetic fractionation was responsible for the strong seasonal trends in S. viminalis n-alkane δ2H values. We suggest that variability in εlw-wax is driven by seasonal differences in the carbohydrate source and thus the NADPH used in n-alkane biosynthesis, with stored carbohydrates utilized during spring and recent occurring growing season assimilates used later in the season. This is further supported by bulk foliar δ13C values, which are 13C-enriched during the period of leaf flush, relative to the end of the growing season. Our results challenge the assumption that biosynthetic fractionation is constant for a given species, and suggest that 2H-enriched stored assimilates are an important source for n-alkane biosynthesis early in the growing season. These findings have implications for the interpretation of sedimentary n-alkanes and call

  6. Effects of application of corn straw on soil microbial community structure during the maize growing season.

    Science.gov (United States)

    Lu, Ping; Lin, Yin-Hua; Yang, Zhong-Qi; Xu, Yan-Peng; Tan, Fei; Jia, Xu-Dong; Wang, Miao; Xu, De-Rong; Wang, Xi-Zhuo

    2015-01-01

    This study investigated the influence of corn straw application on soil microbial communities and the relationship between such communities and soil properties in black soil. The crop used in this study was maize (Zea mays L.). The five treatments consisted of applying a gradient (50, 100, 150, and 200%) of shattered corn straw residue to the soil. Soil samples were taken from May through September during the 2012 maize growing season. The microbial community structure was determined using phospholipid fatty acid (PLFA) analysis. Our results revealed that the application of corn straw influenced the soil properties and increased the soil organic carbon and total nitrogen. Applying corn straw to fields also influenced the variation in soil microbial biomass and community composition, which is consistent with the variations found in soil total nitrogen (TN) and soil respiration (SR). However, the soil carbon-to-nitrogen ratio had no effect on soil microbial communities. The abundance of PLFAs, TN, and SR was higher in C1.5 than those in other treatments, suggesting that the soil properties and soil microbial community composition were affected positively by the application of corn straw to black soil. A Principal Component Analysis indicated that soil microbial communities were different in the straw decomposition processes. Moreover, the soil microbial communities from C1.5 were significantly different from those of CK (p soil and significant variations in the ratio of monounsaturated-to-branched fatty acids with different straw treatments that correlated with SR (p soil properties and soil microbial communities and that these properties affect these communities. The individual PLFA signatures were sensitive indicators that reflected the changes in the soil environment condition. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Pollution Critical Load Exceedance and an Extended Growing Season as Modulators of Red Spruce Radial Growth

    Science.gov (United States)

    Kosiba, A. M.; Schaberg, P. G.; Engel, B. J.; Rayback, S. A.; Hawley, G. J.; Pontius, J.; Miller, E. K.

    2016-12-01

    Acidic sulfur (S) and nitrogen (N) deposition depletes cations such as calcium (Ca) from forest soils and has been linked to increases in foliar winter injury that led to the decline of red spruce (Picea rubens Sarg.) in the northeastern United States. We used results from a 30 m resolution steady-state S and N critical load exceedance model for New England to better understand the spatial connections between Ca depletion and red spruce productivity. To calculate exceedance, atmospheric deposition was estimated for a 5-year period (1984-1988) because tree health and productivity declines were expected to be most responsive to high acid loading. We examined how radial growth (basal area increment) of 441 dominant and co-dominant red spruce trees from 37 sites across Vermont and New Hampshire was related to modeled estimates of S and N critical load exceedance. We assessed growth using statistical models with exceedance as a source of variation, but which also included "year" and "elevation class" (to help account for climatic variability) and interactions among factors. Exceedance was significantly and negatively associated with mean growth for the study period (1951-2010) overall, and particularly for the 1980s and 2000s - periods of numerous and/or severe foliar winter injury events. However, climate-related sources of variation (year and elevation) accounted for most of the differences in growth over the chronology. Interestingly, recent growth for red spruce is now the highest recorded over our dendrochronological record for the species - suggesting that the factors shaping growth may be changing. Because red spruce is a temperate conifer that has the capacity to photosynthesize year-round, it is possible that warmer temperatures may be extending the functional growing season of the species thereby fostering increased growth. Data from elevational transects on Mount Mansfield (Vermont's tallest mountain) indicate that warmer spring, summer, fall and even winter

  8. Terpenoid and carbonyl emissions from Norway spruce in Finland during the growing season

    Science.gov (United States)

    Hakola, Hannele; Tarvainen, Virpi; Praplan, Arnaud P.; Jaars, Kerneels; Hemmilä, Marja; Kulmala, Markku; Bäck, Jaana; Hellén, Heidi

    2017-03-01

    We present spring and summer volatile organic compound (VOC) emission rate measurements from Norway spruce (Picea abies L. Karst) growing in a boreal forest in southern Finland. The measurements were conducted using in situ gas chromatograph with 1 to 2 h time resolution to reveal quantitative and qualitative short-term and seasonal variability of the emissions. The measurements cover altogether 14 weeks in years 2011, 2014 and 2015. Monoterpene (MT) and sesquiterpene (SQT) emission rates were measured all the time, but isoprene only in 2014 and 2015 and acetone and C4-C10 aldehydes only in 2015. The emission rates of all the compounds were low in spring, but MT, acetone, and C4-C10 aldehyde emission rates increased as summer proceeded, reaching maximum emission rates in July. Late summer mean values (late July and August) were 29, 17, and 33 ng g(dw)-1 h-1 for MTs, acetone, and aldehydes respectively. SQT emission rates increased during the summer and highest emissions were measured in late summer (late summer mean value 84 ng g(dw)-1 h-1) concomitant with highest linalool emissions most likely due to stress effects. The between-tree variability of emission pattern was studied by measuring seven different trees during the same afternoon using adsorbent tubes. Especially the contributions of limonene, terpinolene, and camphene were found to vary between trees, whereas proportions of α-pinene (25 ± 5 %) and β-pinene (7 ± 3 %) were more stable. Our results show that it is important to measure emissions at canopy level due to irregular emission pattern, but reliable SQT emission data can be measured only from enclosures. SQT emissions contributed more than 90 % of the ozone reactivity most of the time, and about 70 % of the OH reactivity during late summer. The contribution of aldehydes to OH reactivity was comparable to that of MT during late summer, 10-30 % most of the time.

  9. 317/319 Phytoremediation site monitoring report - 2009 growing season : final report.

    Energy Technology Data Exchange (ETDEWEB)

    Negri, C .N.; Benda, P. L.; Gopalakrishnan, G.; Energy Systems

    2010-02-10

    In 1999, Argonne National Laboratory (Argonne) designed and installed a series of engineered plantings consisting of a vegetative cover system and approximately 800 hybrid poplars and willows rooting at various predetermined depths. The plants were installed using various methods including Applied Natural Science's TreeWell{reg_sign} system. The goal of the installation was to protect downgradient surface and groundwater by intercepting the contaminated groundwater with the tree roots, removing moisture from the upgradient soil area, reducing water infiltration, preventing soil erosion, degrading and/or transpiring the residual volatile organic compounds (VOCs), and removing tritium from the subsoil and groundwater. This report presents the results of the monitoring activities conducted by Argonne's Energy Systems (ES) Division in the growing season of 2009. Monitoring of the planted trees began soon after the trees were installed in 1999 and has been conducted every summer since then. As the trees grew and consolidated their growth into the contaminated soil and groundwater, their exposure to the contaminants was progressively shown through tissue sampling. During the 2009 sampling campaign, VOC concentrations found in the French Drain area were in general consistent with or slightly lower than the 2008 results. Additionally, closely repeated, stand wide analyses showed contaminant fluctuations that may indicate short-term contaminant depletion in the area of interest of roots. This data will be useful to determine short-term removal rate by the trees. As in previous years, levels in the Hydraulic Control Area were close to background levels except for a few exceptions.

  10. Underestimated effects of low temperature during early growing season on carbon sequestration of a subtropical coniferous plantation

    Directory of Open Access Journals (Sweden)

    W.-J. Zhang

    2011-06-01

    Full Text Available The impact of air temperature in early growing season on the carbon sequestration of a subtropical coniferous plantation was discussed through analyzing the eddy flux observations at Qianyanzhou (QYZ site in southern China from 2003 to 2008. This site experienced two cold early growing seasons (with temperature anomalies of 2–5 °C in 2005 and 2008, and a severe summer drought in 2003.
    Results indicated that the low air temperature from January to March was the major factor controlling the inter-annual variations in net carbon uptake at this site, rather than the previously thought summer drought. The accumulative air temperature from January to February showed high correlation (R2=0.970, p<0.001 with the annual net ecosystem production (NEP. This was due to the controls of early-month temperature on the plant phenology developing and the growing season length at this subtropical site. The cold spring greatly shortened the growing season length and therefore reduced the carbon uptake period. The eddy flux observations showed a carbon loss of 4.04 g C m−2 per growing-season day at this coniferous forest site. On the other hand, the summer drought also reduced the net carbon uptake strength because the photosynthesis was more sensitive to water deficit stress than the ecosystem respiration. However, the impact of summer drought occurred within a relatively shorter period and the carbon sequestration went back to the normal level once the drought was relieved.

  11. More CH4 is emitted during the fallow than during the growing season in a Mediterranean rice agrosystems

    Science.gov (United States)

    Martínez-Eixarch, Maite; Ibàñez, Carles; Alcaraz, Carles; Viñas, Marc; Aranda, Xavier; Saldaña, J. Antonio

    2017-04-01

    Paddy rice fields are an important source of greenhouse gas emissions (GHG) as they contribute 5 to 20 % of the global anthropogenic CH4 emissions. The Ebre Delta (Catalonia, NE Spain) is one of the most important wetland complexes in the Western Mediterranean with 65 % of its area covered by rice fields. The results herein presented assess the annual pattern of CH4 emissions from paddy rice in Ebre Delta, including the growing and fallow seasons as well as the major environmental variables modulating such emissions. Fifteen rice fields covering the geo-physical variability of the Ebre Delta were selected for GHG monitoring. Common agronomic management was practiced: water direct-seeding, permanent flooding and moderate mineral fertilization during the growing season and straw incorporation, progressive drainage of the fields after the harvest. Fields are left fallow during the winter. GHG were monthly sampled, from May to December in 2015. In each field, three closed chambers were used; from each of these, four gas samples were taken over a 30-minute period. Simultaneously, hydrological regime, soil physic-chemical parameters and plant cover were measured. GHG were analysed by gas chromatography. A Generalized linear model analysis (GLM) was performed to assess the most important influencing factors on CH4 emissions. An information-theoretic approach was used to find the best approximating models. Overall, the CH4 emissions showed a bi-modal pattern, with peaks in July-August and in October. Emissions rates ranged from 2.1 ± 0.5 to 7.5 ± 1.4 mg C-CH4 m-2 h-1 in the growing season (May to September) and from 25.0 ± 5.7 to 20.1 ± 3.3 mg C-CH4 m-2 h-1 at post-harvest (October to December). In total, 314 kg C-CH4 ha-1 were emitted from Ebre Delta rice fields, of which 70 % during post-harvest. Larger off-season emissions were likely induced by straw incorporation. The results of the GLM-IT analysis revealed that during the growing season, soil Eh and water level

  12. EVALUATION OF RAINFALL-RUNOFF MODELS FOR MEDITERRANEAN SUBCATCHMENTS

    Directory of Open Access Journals (Sweden)

    A. Cilek

    2016-06-01

    Full Text Available The development and the application of rainfall-runoff models have been a corner-stone of hydrological research for many decades. The amount of rainfall and its intensity and variability control the generation of runoff and the erosional processes operating at different scales. These interactions can be greatly variable in Mediterranean catchments with marked hydrological fluctuations. The aim of the study was to evaluate the performance of rainfall-runoff model, for rainfall-runoff simulation in a Mediterranean subcatchment. The Pan-European Soil Erosion Risk Assessment (PESERA, a simplified hydrological process-based approach, was used in this study to combine hydrological surface runoff factors. In total 128 input layers derived from data set includes; climate, topography, land use, crop type, planting date, and soil characteristics, are required to run the model. Initial ground cover was estimated from the Landsat ETM data provided by ESA. This hydrological model was evaluated in terms of their performance in Goksu River Watershed, Turkey. It is located at the Central Eastern Mediterranean Basin of Turkey. The area is approximately 2000 km2. The landscape is dominated by bare ground, agricultural and forests. The average annual rainfall is 636.4mm. This study has a significant importance to evaluate different model performances in a complex Mediterranean basin. The results provided comprehensive insight including advantages and limitations of modelling approaches in the Mediterranean environment.

  13. Calculating High Resolution CWSI Maps for Entire Growing Season of a Cultivated Barley Field with UAV-Collected Surface Temperatures.

    Science.gov (United States)

    Hoffmann, H.; Jensen, R.; Nieto Solana, H.; Friborg, T.; Thomsen, A.

    2015-12-01

    With agriculture as the largest consumer of freshwater and an overall increasing pressure on water resources, developing more efficient irrigation systems is important. Combining the crop water stress index (CWSI) with unmanned aerial vehicles (UAVs) enables detection of which specific areas within a cultivated field that requires irrigation to ensure healthy growing plants. In this study remotely sensed, high resolution surface temperatures are collected with a thermal camera onboard an UAV. Temperatures are used to calculate spatially distributed, high resolution CWSI maps over a barley field during growing seasons 2014 and 2015. In early stages of the barley growing season, surface temperatures are an ensemble of both soil and canopy temperatures. Canopy temperatures are extracted using leaf area index and the two source energy balance modelling scheme. This approach enables CWSI calculations for homogeneous and evenly distributed crops (such as barley) during early as well as late stages of a growing season. CWSI maps are calculated using both an empirical and an analytical approach and are compared and validated against modelled canopy conductance and transpiration rates.

  14. Leaf dynamics of Festulolium and Dactylis glomerata L. at the end of the growing season

    Directory of Open Access Journals (Sweden)

    Jiří Skládanka

    2008-01-01

    Full Text Available The paper is focused on the assessment of leaf extension rate (LER, leaf appearance rate (LAR and leaf senescence rate (LSR in the Festulolium (Festuca arundinacea Schreb. × Lolium multiflorum Lam. and in the Dactylis glomerata L. at the end of the growing season from the end of September to the beginning of December. In summer, the swards were used for a single cut (beginning of June or for a double cut (beginning of June and end of July. Measurements were made in three periods from 14 Sept. to 11 Oct., from 11 Oct. to 29 Oct., and from 29 Oct. to 6 Dec. In the first period, LER was higher in Dactylis glomerata L. (3.770 mm tiller−1 d−1 than in Festulolium (2.376 mm tiller−1 d−1. In the second and third period, LER was higher in Festulolium (0.859 resp. 0.271 mm tiller−1 d−1 than in Dactylis glomerata L. (0.694, resp. 0.199 mm tiller−1 d−1. LAR values measured in Festulolium in the studied pe­riods were 0.277 leaf tiller−1 d−1, 0.079 leaf tiller−1 d−1 and 0.038 leaf tiller−1 d−1 and LAR values of Dactylis glomerata L. were 0.225 leaf tiller−1 d−1, 0.054 leaf tiller−1 d−1 and 0.027 leaf tiller−1 d−1. In the course of the whole pe­riod of study, LSR showed the highest values in Dactylis glomerata L. (7.869 mm til­ler−1 d−1, 5.947 mm til­ler−1 d−1 and 4.757 mm tiller−1 d−1 while the LSR values of Festulolium were lower (2.904 mm tiller−1 d−1, 2.375 mm tiller−1 d−1 and 1.205 mm tiller−1 d−1. The influence of both the species and the period of measurement on the LER, LAR and LSR values was statistically highly significant (P < 0.01 to very highly significant (P < 0.001. The interaction between the species and the period of measurement was very highly significant (P < 0.001 in the LER characteristic. The influence of the intensity of sward use in summer on the LSR values was very highly significant (P < 0.001, too.

  15. Changes to infiltration and soil loss rates during the growing season under conventional and conservation tillage

    Science.gov (United States)

    Jakab, Gergely; Madarász, Balázs; Szabó, Judit; Tóth, Adrienn; Zacháry, Dóra; Szalai, Zoltán; Dyson, Jeremy

    2017-04-01

    Rainfall simulation studies were conducted to determine how infiltration and soil erosion rates vary in field plots under conventional and conservation tillage practices during the growing season: i.) in April while the soil was under green cover; ii.) in May when the soil was a bare seed bed; iii.) in October when the soil was covered in stubble after harvest. At each time, five different rainfall intensities were applied to the plots and the infiltration rate calculated as function of rainfall intensity. The highest infiltration rates were observed on the plot under conservation tillage when it was under the cover crop. Comparing these infiltration rates with those at other times, important differences can be seen. When the soil was prepared as a seedbed, higher infiltration rates occurred when rainfall intensities were less than 80 mm/h. However, when the rainfall intensities were more than 80 mm/h, water infiltration rates were higher when the soil was covered in stubble. This means that natural pore forming processes can be more effective at improving soil drainage potential than temporary improvements created by soil tillage operations. Different methods were used to assess the soil erosion potential. Independently of the method used to calculate soil erodibility, it is obvious that the soil is most vulnerable when prepared as a seedbed. In addition, the highest resistance against soil erosion was observed when the soil was covered with crops. A method of calculating the sediment transporting capacity of runoff found no significant difference between conservation and conventional tillage systems. This contrasts with the Universal Soil Loss Equation method, which indicated differences between the two tillage systems substantial at each time of observation. The lowest difference (less than two times) was when the soil was covered in stubble, which matches with literature data. Overall, conservation tillage resulted in much lower soil erodibility values for the

  16. Estimating subcatchment runoff coefficients using weather radar and a downstream runoff sensor.

    Science.gov (United States)

    Ahm, Malte; Thorndahl, Søren; Rasmussen, Michael R; Bassø, Lene

    2013-01-01

    This paper presents a method for estimating runoff coefficients of urban drainage subcatchments based on a combination of high resolution weather radar data and flow measurements from a downstream runoff sensor. By utilising the spatial variability of the precipitation it is possible to estimate the runoff coefficients of the separate subcatchments. The method is demonstrated through a case study of an urban drainage catchment (678 ha) located in the city of Aarhus, Denmark. The study has proven that it is possible to use corresponding measurements of the relative rainfall distribution over the catchment and downstream runoff measurements to identify the runoff coefficients at subcatchment level.

  17. A bi-proxy reconstruction of Fontainebleau (France growing season temperature from A.D. 1596 to 2000

    Directory of Open Access Journals (Sweden)

    N. Etien

    2008-05-01

    Full Text Available In this paper, we develop a new methodology to estimate past changes of growing season temperature at Fontainebleau (northern France. Northern France temperature fluctuations have been documented by homogenised instrumental temperature records (at most 140 year long and by grape harvest dates (GHD series, incorporated in some of the European-scale temperature reconstructions. We have produced here three new proxy records: δ18O and δ13C of latewood cellulose of living trees and timbers from Fontainebleau Forest and Castle, together with ring widths of the same samples. δ13C data appear to be influenced by tree and age effects; ring widths are not controlled by a single climate parameter. By contrast, δ18O and Burgundy GHD series exhibit strong links with Fontainebleau growing season maximum temperature. Each of these records can also be influenced by other factors such as vine growing practices, local insolation, or moisture availability. In order to reduce the influence of these potential biases, we have used a linear combination of the two records to reconstruct inter-annual fluctuations of Fontainebleau growing season temperature from 1596 to 2000. Over the instrumental period, the reconstruction is well correlated with the temperature data (R2=0.60.

    This reconstruction is associated with an uncertainty of ~1.1°C (1.5 standard deviation, and is expected to provide a reference series for the variability of growing season maximum temperature in Western Europe. Spectral analyses conducted on the reconstruction clearly evidence (i the interest of combining the two proxy records in order to improve the power spectrum of the reconstructed versus observed temperature, (ii changes in the spectral properties over the time, with varying weights of periodicities ranging between ~6 and ~25 years. Available reconstructions of regional growing season temperature fluctuations get

  18. Divergent scaling of respiration rates to nitrogen and phosphorus across four woody seedlings between different growing seasons

    OpenAIRE

    Fan, Ruirui; Sun, Jun; Yang, Fuchun; Li, Man; Zheng, Yuan; Zhong, Quanlin; Cheng, Dongliang

    2017-01-01

    Abstract Empirical studies indicate that the exponents governing the scaling of plant respiration rates (R) with respect to biomass (M) numerically vary between three‐fourth for adult plants and 1.0 for seedlings and saplings and are affected by nitrogen (N) and phosphorus (P) content. However, whether the scaling of R with respect to M (or N and P) varies among different phylogenetic groups (e.g., gymnosperms vs. angiosperms) or during the growing and dormant seasons remains unclear. We meas...

  19. Effects of nitrogen fertilization on the understorey carbon balance over the growing season in a boreal Pine forest

    Science.gov (United States)

    Metcalfe, D. B.; Eisele, B.; Hasselquist, N. J.

    2013-08-01

    Boreal forests play a key role in the global carbon cycle and are facing rapid shifts in nitrogen availability with poorly understood consequences for ecosystem function and global climate. We quantified the effects of nitrogen availability on carbon fluxes from a relatively understudied component of these forests - understorey vegetation - at three intervals over the summer growing period in a northern Swedish Scots Pine stand. Nitrogen addition altered both photosynthetic carbon uptake and respiratory release, but the magnitude and direction of this effect depended on the time during the growing season and the amount of nitrogen added. Specifically, nitrogen addition stimulated net ecosystem carbon uptake only in the late growing season. We find evidence for species-specific control of understorey carbon sink strength, as photosynthesis per unit ground area was positively correlated only with the abundance of the vascular plant Vaccinium myrtillus and no others. Comparison of photosynthetic carbon uptake with data on plant carbon dioxide release from the study site, indicate that understorey vegetation photosynthate was mainly supplying respiratory demands for much of the year. Only in the late season with nitrogen addition did understorey vegetation appear to experience a large surplus of carbon in excess of respiratory requirements. Further work, simultaneously comparing all major biomass and respiratory carbon fluxes in understorey and tree vegetation, is required to resolve the likely impacts of environmental changes on whole-ecosystem carbon sequestration in boreal forests.

  20. Effects of nitrogen fertilization on the forest floor carbon balance over the growing season in a boreal pine forest

    Science.gov (United States)

    Metcalfe, D. B.; Eisele, B.; Hasselquist, N. J.

    2013-12-01

    Boreal forests play a key role in the global carbon cycle and are facing rapid shifts in nitrogen availability with poorly understood consequences for ecosystem function and global climate change. We quantified the effects of increasing nitrogen availability on carbon fluxes from a relatively understudied component of these forests - the forest floor - at three intervals over the summer growing period in a northern Swedish Scots pine stand. Nitrogen addition altered both the uptake and release of carbon dioxide from the forest floor, but the magnitude and direction of this effect depended on the time during the growing season and the amount of nitrogen added. Specifically, nitrogen addition stimulated net forest floor carbon uptake only in the late growing season. We find evidence for species-specific control of forest floor carbon sink strength, as photosynthesis per unit ground area was positively correlated only with the abundance of the vascular plant Vaccinium myrtillus and no others. Comparison of understorey vegetation photosynthesis and respiration from the study site indicates that understorey vegetation photosynthate was mainly supplying respiratory demands for much of the year. Only in the late season with nitrogen addition did understorey vegetation appear to experience a large surplus of carbon in excess of respiratory requirements. Further work, simultaneously comparing all major biomass and respiratory carbon fluxes in forest floor and tree vegetation, is required to resolve the likely impacts of environmental changes on whole-ecosystem carbon sequestration in boreal forests.

  1. Effects of dormant and growing season burning on surface fuels and potential fire behavior in northern Florida longleaf pine (Pinus palustris) flatwoods

    Science.gov (United States)

    James B. Cronan; Clinton S. Wright; Maria Petrova

    2015-01-01

    Prescribed fire is widely used to manage fuels in high-frequency, low-severity fire regimes including pine flatwoods of the southeastern USA where prescribed burning during the growing season (the frost-free period during the calendar year) has become more common in recent decades. Growing season prescribed fires address ecological management objectives that focus on...

  2. Impact of revised and potential future albedo estimates on CCSM3 simulations of growing-season surface temperature fields for North America

    Science.gov (United States)

    Warren E. Heilman; David Y. Hollinger; Xiuping Li; Xindi Bain; Shiyuan. Zhong

    2010-01-01

    Recently published albedo research has resulted in improved growing-season albedo estimates for forest and grassland vegetation. The impact of these improved estimates on the ability of climate models to simulate growing-season surface temperature patterns is unknown. We have developed a set of current-climate surface temperature scenarios for North America using the...

  3. Domination of growing-season evapotranspiration over runoff makes ditch network maintenance in mature peatland forests questionable

    Directory of Open Access Journals (Sweden)

    S. Sarkkola

    2013-04-01

    Full Text Available In Finland, ditch network maintenance (DNM is carried out annually on 60–70,000 ha of drained peatland to promote tree growth for forestry purposes. However, it is important to avoid ditching that contributes little to the stand growth and productivity, both to improve the economical profitability of forestry and to mitigate DNM-induced nutrient release to watercourses. We hypothesised that mature forest stands with substantial evapotranspiration potential do not necessarily need DNM, even if the ditch networks are in poor condition.We estimated evapotranspiration (EVT of forest vegetation during the growing seasons (June–September of 2007–2011 in four forested artificial peatland catchments dominated by Scots pine stands (Pinus sylvestris L. (stand volume 93–151 m3 ha-1 located in southern, western, central and northern Finland. Precipitation (P, runoff (R and water table level (WTL were monitored continuously in the field. The water storage change (ΔS was estimated on the basis of WTL measurements and peat pF curves determined from in situ peat samples. In addition, tree stand transpiration (T was estimated in two of the catchments using the sap flow method. EVT was estimated as the residual term of the water balance equation.During the growing season, EVT (153–295 mm was 49–161 % of the total accumulated P (155–368 mm, and decreased from south to north. Within each growing season, EVT was always largest in July or August. Tree transpiration was about 50 % of the total forest EVT in the two sites where it was measured directly. The mean WTL was at depth 36–63 cm during the growing seasons. Clear-cutting of a 100m3 ha-1 stand on one site resulted in an average rise of WTL by 18 cm.The results suggested that, in the southernmost site in particular, no drainage network management would be necessary to sustain satisfactory drainage conditions for tree growth because growing-season precipitation is transferred back to the

  4. Longer growing seasons and warm summers boost Rhododendron ferrugineum L. growth in the Taillefer massif (French Alps)

    Science.gov (United States)

    Francon, Loïc; Corona, Christophe; Roussel, Erwan; Lopez Saez, Jerome; Stoffel, Markus

    2017-04-01

    Rhododendron ferrugineum L. is an important and widespread dwarf shrub species growing in high-elevation, alpine environments of the Western European Alps. As such, it is likely to offer unique opportunities which would allow pushing current dendrochronological networks into extreme environments and way beyond the upper survival limit of trees. Given that different species of the same genus have been successfully used in tree-ring investigations, notably in the Himalayas where Rhododendron sp. has proven to be a reliable climate proxy, this study aims at (i) evaluating the dendroclimatological potential of the widely distributed R. ferrugineum and at (ii) determining the major limiting climate factor driving species growth and the formation of rings. To this end, 154 cross-sections from 36 R. ferrugineum individuals have been sampled above local treelines and at elevations comprised between 1800 and 2100 m asl on NW-facing slopes of the Taillefer massif (French Alps). We illustrate a 195-year-long standard chronology based on growth-ring records selected from 24 individuals, and document that the series is well-replicated for almost one century (1920-2015) with an Expressed Population Signal (EPS) >0.85. Analysis using partial and seasonal correlation functions further highlight that growth of Rhododendron is governed by temperatures during the growing season (May-July), with increasingly higher air temperatures favoring larger ring widths, a phenomenon which is well known from dwarf shrubs growing in circum-arctic tundra ecosystems. Similarly, the negative effect of January-February precipitation on radial growth of R. ferrugineum, rarely observed in the Arctic, is interpreted as a result of reduced growing seasons following snowy winters. We conclude that the strong and unequivocal signals recorded in the fairly long R. ferrugineum chronologies presented here can indeed be used for climate-growth studies as well as for the reconstruction of climatic fluctuations

  5. Physiological responses of birch (Betula pendula) to ozone: a comparison between open-soil-grown trees exposed for six growing seasons and potted seedlings exposed for one season

    Energy Technology Data Exchange (ETDEWEB)

    Oksanen, E. [Kuopio Univ., Dept. of Ecology and Environmental Science, Kuopio (Finland)

    2003-06-01

    Physiological responses to ozone exposure over one growing season of four year-old potted ozone-tolerant white birch saplings were compared with saplings of six year-old open-soil-grown trees of the same birch variety that has been previously fumigated with ozone for five growing season. Both plant groups were exposed to ambient and elevated ozone concentrations under similar microclimatic conditions in a free air ozone exposure facility. Growth in foliage, net photosynthesis, stomatal conductance, starch and nutrient concentrations and differences in ozone responses between lower, middle and upper sections of the canopy were determined. Potted saplings showed no effect to elevated ozone concentration, while the open-soil-grown trees showed a 3 to 38 per cent reduction in shoot growth, a 22 per cent reduction in the number of overwintering buds, a 26-65 per cent decrease in net annual photosynthesis, 30 per cent reduction in starch, and a 20-23 per cent reduction in nitrogen concentration, as well as disturbances in stomatal conductance. Various explanations are offered for the higher ozone sensitivity of open-soil-grown trees, among them cumulative carry-over effects of multi-year exposure resulting in impaired bud formation, reduced capacity for photosynthetic compensation for ozone damage, and slower leaf senescence. The main conclusion was that in European white birch exposure period and plant size were the most important factors affecting ozone tolerance. 46 refs., 2 tabs., 6 figs.

  6. Partitioning the grapevine growing season in the Douro Valley of Portugal: accumulated heat better than calendar dates.

    Science.gov (United States)

    Real, António C; Borges, José; Cabral, J Sarsfield; Jones, Gregory V

    2015-08-01

    Temperature and water status profiles during the growing season are the most important factors influencing the ripening of wine grapes. To model weather influences on the quality and productivity of the vintages, it is necessary to partition the growing season into smaller growth intervals in which weather variables are evaluated. A significant part of past and ongoing research on the relationships between weather and wine quality uses calendar-defined intervals to partition the growing season. The phenology of grapevines is not determined by calendar dates but by several factors such as accumulated heat. To examine the accuracy of different approaches, this work analyzed the difference in average temperature and accumulated precipitation using growth intervals with boundaries defined by means of estimated historical phenological dates and intervals defined by means of accumulated heat or average calendar dates of the Douro Valley of Portugal. The results show that in situations where there is an absence of historical phenological dates and/or no available data that makes the estimation of those dates possible, it is more accurate to use grapevine heat requirements than calendar dates to define growth interval boundaries. Additionally, we analyzed the ability of the length of growth intervals with boundaries based on grapevine heat requirements to differentiate the best from the worst vintage years with the results showing that vintage quality is strongly related to the phenological events. Finally, we analyzed the variability of growth interval lengths in the Douro Valley during 1980-2009 with the results showing a tendency for earlier grapevine physiology.

  7. Interannual Variations in Growing-Season NDVI and Its Correlation with Climate Variables in the Southwestern Karst Region of China

    Directory of Open Access Journals (Sweden)

    Wenjuan Hou

    2015-08-01

    Full Text Available In this study, the updated Global Inventory Modeling and Mapping Studies (GIMMS Normalized Difference Vegetation Index (NDVI dataset for growing season (April to October, which can better reflect the vegetation vigor, was used to investigate the interannual variations in NDVI and its relationship with climatic factors, in order to preliminarily understand the climate impact on vegetation and provide theoretical basis for the response of ecosystem to climate change. Multivariate linear regression models, including the Ordinary Least Squares (OLS and Geographically Weighted Regression (GWR, were adopted to analyze the correlation between NDVI and climatic factors (temperature and precipitation together. Average growing-season NDVI significantly increased at a rate of 0.0015/year from 1982 to 2013, larger than several regions in China. On the whole, its relationship with temperature is positive and also stronger than precipitation, which indicated that temperature may be a limiting factor for the vegetation growth in the Karst region. Moreover, the correlation coefficients between grassland NDVI and climatic factors are the largest. Under the background of NDVI increasing trend from 1982 to 2013, the period of 2009–2012 was chosen to investigate the influencing factors of a sharp decline in NDVI. It can be found that the reduced temperature and solar radiation, caused by the increase in cloud cover and precipitation, may play important roles in the vegetation cover change. All in all, the systematic research on the interannual variations of growing-season NDVI and its relationship with climate revealed the heterogeneity and variability in the complicated climate change in the Karst ecosystem for the study area. It is the Karst characteristics that hinder obtaining more representative conclusions and tendencies in this region. Hence, more attention should be paid to promoting Karst research in the future.

  8. Landscape controls on the timing of spring, autumn, and growing season length in mid-Atlantic forests

    Science.gov (United States)

    Elmore, A.J.; Guinn, S.M.; Minsley, B.J.; Richardson, A.D.

    2012-01-01

    The timing of spring leaf development, trajectories of summer leaf area, and the timing of autumn senescence have profound impacts to the water, carbon, and energy balance of ecosystems, and are likely influenced by global climate change. Limited field-based and remote-sensing observations have suggested complex spatial patterns related to geographic features that influence climate. However, much of this variability occurs at spatial scales that inhibit a detailed understanding of even the dominant drivers. Recognizing these limitations, we used nonlinear inverse modeling of medium-resolution remote sensing data, organized by day of year, to explore the influence of climate-related landscape factors on the timing of spring and autumn leaf-area trajectories in mid-Atlantic, USA forests. We also examined the extent to which declining summer greenness (greendown) degrades the precision and accuracy of observations of autumn offset of greenness. Of the dominant drivers of landscape phenology, elevation was the strongest, explaining up to 70% of the spatial variation in the onset of greenness. Urban land cover was second in importance, influencing spring onset and autumn offset to a distance of 32 km from large cities. Distance to tidal water also influenced phenological timing, but only within ~5 km of shorelines. Additionally, we observed that (i) growing season length unexpectedly increases with increasing elevation at elevations below 275 m; (ii) along gradients in urban land cover, timing of autumn offset has a stronger effect on growing season length than does timing of spring onset; and (iii) summer greendown introduces bias and uncertainty into observations of the autumn offset of greenness. These results demonstrate the power of medium grain analyses of landscape-scale phenology for understanding environmental controls on growing season length, and predicting how these might be affected by climate change.

  9. Partitioning the grapevine growing season in the Douro Valley of Portugal: accumulated heat better than calendar dates

    Science.gov (United States)

    Real, António C.; Borges, José; Cabral, J. Sarsfield; Jones, Gregory V.

    2015-08-01

    Temperature and water status profiles during the growing season are the most important factors influencing the ripening of wine grapes. To model weather influences on the quality and productivity of the vintages, it is necessary to partition the growing season into smaller growth intervals in which weather variables are evaluated. A significant part of past and ongoing research on the relationships between weather and wine quality uses calendar-defined intervals to partition the growing season. The phenology of grapevines is not determined by calendar dates but by several factors such as accumulated heat. To examine the accuracy of different approaches, this work analyzed the difference in average temperature and accumulated precipitation using growth intervals with boundaries defined by means of estimated historical phenological dates and intervals defined by means of accumulated heat or average calendar dates of the Douro Valley of Portugal. The results show that in situations where there is an absence of historical phenological dates and/or no available data that makes the estimation of those dates possible, it is more accurate to use grapevine heat requirements than calendar dates to define growth interval boundaries. Additionally, we analyzed the ability of the length of growth intervals with boundaries based on grapevine heat requirements to differentiate the best from the worst vintage years with the results showing that vintage quality is strongly related to the phenological events. Finally, we analyzed the variability of growth interval lengths in the Douro Valley during 1980-2009 with the results showing a tendency for earlier grapevine physiology.

  10. Climate change and prolongation of growing season: changes in regional potential for field crop production in Finland

    Directory of Open Access Journals (Sweden)

    P. PELTONEN-SAINIO

    2008-12-01

    Full Text Available Climate change offers new opportunities for Finnish field crop production, which is currently limited by the short growing season. A warmer climate will extend the thermal growing season and the physiologically effective part of it. Winters will also become milder, enabling introduction of winter-sown crops to a greater extent than is possible today. With this study we aim to characterise the likely regional differences in capacity to grow different seed producing crops. Prolongation of the Finnish growing season was estimated using a 0.5º latitude × 0.5º longitude gridded dataset from the Finnish Meteorological Institute. The dataset comprised an average estimate from 19 global climate models of the response of Finnish climate to low (B1 and high (A2 scenarios of greenhouse gas and aerosol emissions for 30-year periods centred on 2025, 2055 and 2085 (Intergovernmental Panel on Climate Change. Growing season temperature sums that suit crop growth and are agronomically feasible in Finland are anticipated to increase by some 140 °Cd by 2025, 300 °Cd by 2055 and 470 °Cd by 2085 in scenario A2, when averaged over regions, and earlier sowing is expected to take place, but not later harvests. Accordingly, the extent of cultivable areas for the commonly grown major and minor crops will increase considerably. Due to the higher base temperature requirement for maize (Zea mays L. growth than for temperate crops, we estimate that silage maize could become a Finnish field crop for the most favourable growing regions only at the end of this century. Winters are getting milder, but it will take almost the whole century until winters such as those that are typical for southern Sweden and Denmark are experienced on a wide scale in Finland. It is possible that introduction of winter-sown crops (cereals and rapeseed will represent major risks due to fluctuating winter conditions, and this could delay their adaptation for many decades. Such risks need to be

  11. Health at the Sub-catchment Scale: Typhoid and Its Environmental Determinants in Central Division, Fiji.

    Science.gov (United States)

    Jenkins, Aaron Peter; Jupiter, Stacy; Mueller, Ute; Jenney, Adam; Vosaki, Gandercillar; Rosa, Varanisese; Naucukidi, Alanieta; Mulholland, Kim; Strugnell, Richard; Kama, Mike; Horwitz, Pierre

    2016-12-01

    The impact of environmental change on transmission patterns of waterborne enteric diseases is a major public health concern. This study concerns the burden and spatial nature of enteric fever, attributable to Salmonella Typhi infection in the Central Division, Republic of Fiji at a sub-catchment scale over 30-months (2013-2015). Quantitative spatial analysis suggested relationships between environmental conditions of sub-catchments and incidence and recurrence of typhoid fever. Average incidence per inhabited sub-catchment for the Central Division was high at 205.9/100,000, with cases recurring in each calendar year in 26% of sub-catchments. Although the numbers of cases were highest within dense, urban coastal sub-catchments, the incidence was highest in low-density mountainous rural areas. Significant environmental determinants at this scale suggest increased risk of exposure where sediment yields increase following runoff. The study suggests that populations living on large systems that broaden into meandering mid-reaches and floodplains with alluvial deposition are at a greater risk compared to small populations living near small, erosional, high-energy headwaters and small streams unconnected to large hydrological networks. This study suggests that anthropogenic alteration of land cover and hydrology (particularly via fragmentation of riparian forest and connectivity between road and river networks) facilitates increased transmission of typhoid fever and that environmental transmission of typhoid fever is important in Fiji.

  12. Impact of Faba Bean-Seed Rhizobial Inoculation on Microbial Activity in the Rhizosphere Soil during Growing Season.

    Science.gov (United States)

    Siczek, Anna; Lipiec, Jerzy

    2016-05-20

    Inoculation of legume seeds with Rhizobium affects soil microbial community and processes, especially in the rhizosphere. This study aimed at assessing the effect of Rhizobium inoculation on microbial activity in the faba bean rhizosphere during the growing season in a field experiment on a Haplic Luvisol derived from loess. Faba bean (Vicia faba L.) seeds were non-inoculated (NI) or inoculated (I) with Rhizobium leguminosarum bv. viciae and sown. The rhizosphere soil was analyzed for the enzymatic activities of dehydrogenases, urease, protease and acid phosphomonoesterase, and functional diversity (catabolic potential) using the Average Well Color Development, Shannon-Weaver, and Richness indices following the community level physiological profiling from Biolog EcoPlate™. The analyses were done on three occasions corresponding to the growth stages of: 5-6 leaf, flowering, and pod formation. The enzymatic activities were higher in I than NI (p < 0.05) throughout the growing season. However, none of the functional diversity indices differed significantly under both treatments, regardless of the growth stage. This work showed that the functional diversity of the microbial communities was a less sensitive tool than enzyme activities in assessment of rhizobial inoculation effects on rhizosphere microbial activity.

  13. Estimating Water Footprints of Vegetable Crops: Influence of Growing Season, Solar Radiation Data and Functional Unit

    Directory of Open Access Journals (Sweden)

    Betsie le Roux

    2016-10-01

    Full Text Available Water footprint (WF accounting as proposed by the Water Footprint Network (WFN can potentially provide important information for water resource management, especially in water scarce countries relying on irrigation to help meet their food requirements. However, calculating accurate WFs of short-season vegetable crops such as carrots, cabbage, beetroot, broccoli and lettuce presented some challenges. Planting dates and inter-annual weather conditions impact WF results. Joining weather datasets of just rainfall, minimum and maximum temperature with ones that include solar radiation and wind-speed affected crop model estimates and WF results. The functional unit selected can also have a major impact on results. For example, WFs according to the WFN approach do not account for crop residues used for other purposes, like composting and animal feed. Using yields in dry matter rather than fresh mass also impacts WF metrics, making comparisons difficult. To overcome this, using the nutritional value of crops as a functional unit can connect water use more directly to potential benefits derived from different crops and allow more straightforward comparisons. Grey WFs based on nitrogen only disregards water pollution caused by phosphates, pesticides and salinization. Poor understanding of the fate of nitrogen complicates estimation of nitrogen loads into the aquifer.

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

    Science.gov (United States)

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

    2014-12-01

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

  15. Climatic warming above the Arctic Circle: are there trends in timing and length of the thermal growing season in Murmansk Region (Russia) between 1951 and 2012?

    Science.gov (United States)

    Blinova, Ilona; Chmielewski, Frank-Michael

    2015-06-01

    Anomalies in the timing of the thermal growing season have become obvious in the NE part of Fennoscandia since 2000. They are in accordance with climatic changes reported for Europe and Fennoscandia. The actual length of the growing season reached 120 days on average, onset on 30 May and ending on 27 September (1981-2010). Shifts in the timing of the growing season and its mean prolongation by 18.5 days/62a are demonstrated for Murmansk Region (1951-2012). In this period, the onset of the growing season advanced by 7.1 days/62a, while the end was extended by 11.4 days/62a. The delay in the end of the growing season is similar to the entire Fennoscandian pattern but it has not been detected in the rest of Europe. The regional pattern of climatic regimes in Murmansk Region remained stable in comparison with earlier climatic maps (1971). However, the actual shifts in the timing of the growing season were more pronounced in colder (oceanic and mountainous) parts. Recent climatic trends could influence the retreat of the tundra zone and changes in the forest line. Losses of tundra biodiversity and enrichment of the northern taiga by southern species could be expected from present climatic trends.

  16. Verification of satellite radar remote sensing based estimates of boreal and subalpine growing seasons using an ecosystem process model and surface biophysical measurement network information

    Science.gov (United States)

    McDonald, K. C.; Kimball, J. S.; Zimmerman, R.

    2002-01-01

    We employ daily surface Radar backscatter data from the SeaWinds Ku-band Scatterometer onboard Quikscat to estimate landscape freeze-thaw state and associated length of the seasonal non-frozen period as a surrogate for determining the annual growing season across boreal and subalpine regions of North America for 2000 and 2001.

  17. Leaf ontogeny dominates the seasonal exchange of volatile organic compounds (VOC) in a SRC-poplar plantation during an entire growing season

    Science.gov (United States)

    Brilli, Federico; Gioli, Beniamino; Fares, Silvano; Zenone, Terenzio; Zona, Donatella; Gielen, Bert; Loreto, Francesco; Janssens, Ivan; Ceulemans, Reinhart

    2015-04-01

    The declining cost of many renewable energy technologies and changes in the prices of fossil fuels have recently encouraged governments policies to subsidize the use of biomass as a sustainable source of energy. Deciduous poplars (Populus spp.) trees are often selected for biomass production in short rotation coppiced (SRC) for their high CO2 photosynthetic assimilation rates and their capacity to develop dense canopies with high values of leaf area index (LAI). So far, observations and projections of seasonal variations of many VOC fluxes has been limited to strong isoprenoids emitting evergreen ecosystems such tropical and Mediterranean forests as well as Citrus and oil palm plantation, all having constant values of LAI. We run a long-term field campaign where the exchange of VOC, together with CO2 and water vapor was monitored during an entire growing season (June - November, 2012) above a SRC-based poplar plantation. Our results confirmed that isoprene and methanol were the most abundant fluxes emitted, accounting for more than 90% of the total carbon released in form of VOC. However, Northern climates characterized by fresh summertime temperatures and recurring precipitations favored poplar growth while inhibiting the development of isoprene emission that resulted in only 0.7% of the net ecosystem carbon exchange (NEE). Besides, measurements of a multitude of VOC fluxes by PTR-TOF-MS showed bi-directional exchange of oxygenated-VOC (OVOC) such as: formaldehyde, acetaldehyde, acetone, isoprene oxidation products (iox, namely MVK, MAC and MEK) as well as ethanol and formic acid. The application of Self Organizing Maps to visualize the relationship between the full time-series of many VOC fluxes and the observed seasonal variations of environmental, physiological and structural parameters proved the most abundant isoprene ad methanol fluxes to occur mainly on the hottest days under mid-high light intensities when also NEE and evapotraspiration reached the highest

  18. Downscaling 250-m MODIS growing season NDVI based on multiple-date landsat images and data mining approaches

    Science.gov (United States)

    Gu, Yingxin; Wylie, Bruce K.

    2015-01-01

    The satellite-derived growing season time-integrated Normalized Difference Vegetation Index (GSN) has been used as a proxy for vegetation biomass productivity. The 250-m GSN data estimated from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensors have been used for terrestrial ecosystem modeling and monitoring. High temporal resolution with a wide range of wavelengths make the MODIS land surface products robust and reliable. The long-term 30-m Landsat data provide spatial detailed information for characterizing human-scale processes and have been used for land cover and land change studies. The main goal of this study is to combine 250-m MODIS GSN and 30-m Landsat observations to generate a quality-improved high spatial resolution (30-m) GSN database. A rule-based piecewise regression GSN model based on MODIS and Landsat data was developed. Results show a strong correlation between predicted GSN and actual GSN (r = 0.97, average error = 0.026). The most important Landsat variables in the GSN model are Normalized Difference Vegetation Indices (NDVIs) in May and August. The derived MODIS-Landsat-based 30-m GSN map provides biophysical information for moderate-scale ecological features. This multiple sensor study retains the detailed seasonal dynamic information captured by MODIS and leverages the high-resolution information from Landsat, which will be useful for regional ecosystem studies.

  19. Evaluation of the infiltration capacity of soil in a winter wheat stand during the growing season 2010

    Directory of Open Access Journals (Sweden)

    Tomáš Mašíček

    2011-01-01

    Full Text Available The aim of the presented paper was to map the course of infiltration during the growing season of 2010 in a winter wheat stand on a selected locality in the Sazomín cadastral area on the basis of selected hydro-physical properties of soil (specific weight, reduced volume weight, actual soil moisture, absorptivity, retention water capacity, porosity, capillary, semi-capillary and non-capillary pores and aeration evaluated from the analyses of undisturbed soil samples. In order to assess the infiltration capacity of soil at the U Jasana locality in the season April–October, four surveys were realized always with three measurements within each of the surveys. The measurement of infiltration took place in the form of basin irrigation. To evaluate field measurements of infiltration empirical relations were used, namely Kostiakov equations. The highest cumulative infiltration and speed of infiltration were noted in June at the high actual soil moisture and closed stand. In case of October measurement, effects of agro-technical operations became evident on the slightly lower infiltration capacity of soil as compared to June measurements at nearly identical moisture conditions. The lowest infiltration capacity of soil reaching the same level, namely in spite of different moisture conditions and the stand character (July – full-grown stand, August – stubble-field was found in July and August.

  20. Estimating Subcatchment Runoff Coefficients using Weather Radar and a Downstream Runoff Sensor

    DEFF Research Database (Denmark)

    Ahm, Malte; Thorndahl, Søren Liedtke; Rasmussen, Michael R.

    2013-01-01

    This paper presents a method for estimating runoff coefficients of urban drainage subcatchments based on a combination of high resolution weather radar data and flow measurements from a downstream runoff sensor. By utilising the spatial variability of the precipitation it is possible to estimate...

  1. Factors Affecting the Content of Ergosterol and Zearalenone in Selected Grass Species at the End of the Growing Season

    Directory of Open Access Journals (Sweden)

    Jiří Skládanka

    2009-01-01

    Full Text Available The objective of the study was to assess the safety of forage prepared from selected grass species by means of the analysis of ergosterol and zearalenone. Graminaceous plants studied at the end of their growing season were Festulolium, Dactylis glomerata and Arrhenatherum elatius. Other indicators assessed were the content of ergosterol and zearalenone during the autumn and the intensity of grassland use in the summer season as related to the studied contents of metabolites. Grasslands were harvested either in October, November or December. The secondary metabolites were analyzed by means of high performance liquid chromatography. At the end of the growing season, the ergosterol content was the lowest in the Festulolium forage (110.04 mg kg-1, the highest contents were observed in the Dactylis glomerata and Arrhenatherum elatius forages (145.73 mg kg-1 and 139.55 mg kg-1, respectively. The safety of Festulolium was also corroborated by the low zearalenone content (0.357 mg kg-1. On the other hand, the high ergosterol content in Arrhenatherum elatius was combined with a high content of zearalenone (1.554 mg kg-1. Although Dactylis glomerata exhibited an ergosterol content comparable with that of Arrhenatherum elatius forage, its zearalenone content was comparable to the Festulolium forage. Among the three species under study we found a significant difference (P P -1. The higher (P -1 was caused by the Arrhenatherum elatius forage. Moreover, the contents of ergosterol and zearalenone were affected (P < 0.01 also by the number of cuts in summer. The higher ergosterol content indicated a higher forage infestation by fungi and the inherent risk of the occurrence of mycotoxins. However, the high ergosterol content not always correlated with the high content of zearalenone. When cattle is grazing in winter, a higher occurrence of mycotoxins in the feed may be expected and the related damage to animal metabolism may increase the number of diseased

  2. Spatial and Temporal Variability in the Onset of the Growing Season on Svalbard, Arctic Norway — Measured by MODIS-NDVI Satellite Data

    Directory of Open Access Journals (Sweden)

    Stein Rune Karlsen

    2014-08-01

    Full Text Available The Arctic is among the regions with the most rapid changes in climate and has the expected highest increase in temperature. Changes in the timing of phenological phases, such as onset of the growing season observed from remote sensing, are among the most sensitive bio-indicators of climate change. The study area here is the High Arctic archipelago of Svalbard, located between 76°30ʹ and 80°50ʹN. The goal of this study was to use MODIS Terra data (the MOD09Q1 and MOD09A1 surface reflectance products, both with 8-day temporal composites to map the onset of the growing season on Svalbard for the 2000–2013 period interpreted from field observations. Due to a short and intense period with greening-up and frequent cloud cover, all the cloud free data is needed, which requires reliable cloud masks. We used a combination of three cloud removing methods (State QA values, own algorithms, and manual removal. This worked well, but is time-consuming as it requires manual interpretation of cloud cover. The onset of the growing season was then mapped by a NDVI threshold method, which showed high correlation (r2 = 0.60, n = 25, p < 0.001 with field observations of flowering of Salix polaris (polar willow. However, large bias was found between NDVI-based mapped onset and field observations in bryophyte-dominated areas, which indicates that the results in these parts must be interpreted with care. On average for the 14-year period, the onset of the growing season occurs after July 1st in 68.4% of the vegetated areas of Svalbard. The mapping revealed large variability between years. The years 2000 and 2008 were extreme in terms of late onset of the growing season, and 2002 and 2013 had early onset. Overall, no clear trend in onset of the growing season for the 2000–2013 period was found.

  3. Silvicultural options in ageing holm oak (Quercus ilex L. coppices in Gargano: results after 14 growing seasons

    Directory of Open Access Journals (Sweden)

    Scopigno D

    2008-12-01

    Full Text Available In the frame of a long-term research program concerning management of ageing holm oak coppices, results available after 14 growing seasons are reported in present paper. Experimental treatments include: A 50 standards per hectare, all of the same age; B 250 standards per hectare, all of the same age; C 140 standards per hectare, with two different ages; D conversion to high forest; E natural evolution (control. A total of 15 permanent plots were established (5 treatments x 3 replicates per treatment and the experimental design used is that of randomised blocks. Based on observations concerning seedlings and shoots development and standards growth and competitive effects, the following preliminary results may be highlighted: i recovering the traditional coppicing system with few standards per hectare represents a valid option from both ecological and shoots growth point of view; the stools, with few standards per hectare, showed a larger number of sprouts, provided with a higher average height and larger diameters; ii uneven-aged standards represent a good alternative form the points of view of both landscape impact immediately after felling operations and stand resistance to climatic damages; iii a good alternative is to apply conversion treatments to high forest, whenever their site quality allows these operations.

  4. Wet and Dry Atmospheric Depositions of Inorganic Nitrogen during Plant Growing Season in the Coastal Zone of Yellow River Delta

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    Junbao Yu

    2014-01-01

    Full Text Available The ecological problems caused by dry and wet deposition of atmospheric nitrogen have been widespread concern in the world. In this study, wet and dry atmospheric depositions were monitored in plant growing season in the coastal zone of the Yellow River Delta (YRD using automatic sampling equipment. The results showed that SO42- and Na+ were the predominant anion and cation, respectively, in both wet and dry atmospheric depositions. The total atmospheric nitrogen deposition was ~2264.24 mg m−2, in which dry atmospheric nitrogen deposition was about 32.02%. The highest values of dry and wet atmospheric nitrogen deposition appeared in May and August, respectively. In the studied area, NO3-–N was the main nitrogen form in dry deposition, while the predominant nitrogen in wet atmospheric deposition was NH4+–N with ~56.51% of total wet atmospheric nitrogen deposition. The average monthly attribution rate of atmospheric deposition of NO3-–N and NH4+–N was ~31.38% and ~20.50% for the contents of NO3-–N and NH4+–N in 0–10 cm soil layer, respectively, suggested that the atmospheric nitrogen was one of main sources for soil nitrogen in coastal zone of the YRD.

  5. OpenLISEM Flash Flood Modelling Application in Logung Sub-Catchment, Central Java

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    Fitrie Atviana Nurritasari

    2016-02-01

    Full Text Available Juwana Catchment and Logung Sub-catchment in particular has been suffering several major past flood events with significant loss. This study conducted an assessment of flood risk by using OpenLISEM as physical soil and hydrological model to generate the single storm flash flood occurrences. The physical input data were collected from remote sensing image interpretation, field observation and measurement and literature review. There are three return periods chosen as scenarios that represent rainfall intensity in Logung Sub-Catchment. Model validation was done by adjusting initial moisture content and saturated hydraulic conductivity values to equate the calculated total discharge with the measured total discharge in several chosen dates. The results show increases in most of modeled hydrological parameter with respect to increasing of rainfall intensity.

  6. Case study to examine the effects of a growing-season burn and annosum root disease on mortality in a longleaf pine stand

    Science.gov (United States)

    Michelle M. Cram; Dan Shea; Ken Forbus

    2010-01-01

    A case study of a growing-season burn in a longleaf pine (Pinus palustris) stand affected by annosum root disease was conducted at Savannah River Site, SC. The project utilized a longleaf pine stand from a 1995 evaluation of a stump applicator system. The Tim-bor® (disodium octaborate tetrahydrate) and no stump treatment blocks (NST) were...

  7. Effects of fire disturbance on soil respiration in the non-growing season in a Larix gmelinii forest in the Daxing'an Mountains, China.

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    Tongxin Hu

    Full Text Available In boreal forests, fire is an important part of the ecosystem that greatly influences soil respiration, which in turn affects the carbon balance. Wildfire can have a significant effect on soil respiration and it depends on the fire severity and environmental factors (soil temperature and snow water equivalent after fire disturbance. In this study, we quantified post-fire soil respiration during the non-growing season (from November to April in a Larix gmelinii forest in Daxing'an Mountains of China. Soil respiration was measured in the snow-covered and snow-free conditions with varying degrees of natural burn severity forests. We found that soil respiration decreases as burn severity increases. The estimated annual C efflux also decreased with increased burn severity. Soil respiration during the non-growing season approximately accounted for 4%-5% of the annual C efflux in all site types. Soil temperature (at 5 cm depth was the predominant determinant of non-growing season soil respiration change in this area. Soil temperature and snow water equivalent could explain 73%-79% of the soil respiration variability in winter snow-covering period (November to March. Mean spring freeze-thaw cycle (FTC period (April soil respiration contributed 63% of the non-growing season C efflux. Our finding is key for understanding and predicting the potential change in the response of boreal forest ecosystems to fire disturbance under future climate change.

  8. Comparison of planted loblolly, longleaf, and slash pine development through 10 growing seasons in central Louisiana--an argument for longleaf pine

    Science.gov (United States)

    James D. Haywood; Mary Anne S. Sayer; Shi-Jean Susana Sung

    2015-01-01

    Two studies were established in central Louisiana to compare development of planted loblolly (Pinus taeda L.), longleaf (P. palustris Mill.), and slash (P. elliottii Engelm.) pine. Study 1 was on a Beauregard silt loam, and Study 2 was on Ruston and McKamie fine sandy loams. After 10 growing seasons,...

  9. Effect of soil frost on growing season nitrogen uptake by fine roots of mature trees in northern hardwood forests of the United States

    Science.gov (United States)

    Socci, A. M.; Templer, P. H.

    2010-12-01

    Forests of the northeastern United States are predicted to experience a decrease in the depth and duration of the winter snowpack over the next 100 years. Even when coupled with warmer winter air temperatures, the absence of snow as insulation can increase soil frost during the winter months. Past research has determined that there are species-level effects of soil frost on dominant forest trees. For example, in stands dominated by sugar maple (Acer saccharum), induced soil frost led to increased fine root mortality and soil nitrate leaching. Soil frost also increased fine root mortality in stands dominated by yellow birch (Betula allegheniensis), but there was no significant change in leaching of soil nitrate. We hypothesized that greater nitrogen (N) losses from stands dominated by sugar maple may be due to reduced N uptake by fine roots of this tree species. To determine the impact of increased soil freezing on fine root uptake of N, we established a snow manipulation experiment in mixed sugar maple/American beech (Fagus grandifolia) forests at the Hubbard Brook Experimental Forest in New Hampshire (n=4 paired snow-removal and reference plots; each 13m X 13m). Snow removal occurred during the first six weeks of winter over two years. During each growing season following snow removal, we used the N depletion technique to measure in situ rates of uptake of ammonium and nitrate by fine roots of sugar maple during the early, peak and late growing season. Among all sampling dates and plots, we observed significantly lower uptake of N as nitrate compared to ammonium. During the first growing season, at moderate ammonium availability (35 μM N) we observed significantly less uptake of ammonium by fine roots of sugar maple in the snow removal plots relative to the reference plots during the early growing season (April-May), with no significant differences in uptake of ammonium during the peak (July) and late (September) growing season. We observed no differences in

  10. Soil nitrogen transformations under elevated atmospheric CO{sub 2} and O{sub 3} during the soybean growing season

    Energy Technology Data Exchange (ETDEWEB)

    Pujol Pereira, Engil Isadora, E-mail: isapereira@ucdavis.ed [Department of Plant Sciences, University of California - Davis, One Shields Avenue, Davis, CA 95616 (United States); Chung, Haegeun [Division of Environmental Science and Ecological Engineering, Korea University, Anam-dong, Seongbuk-gu, Seoul 136-701 (Korea, Republic of); Scow, Kate [Department of Land, Air, and Water Resources, University of California, Davis, One Shields Avenue, Davis, CA 95616 (United States); Sadowsky, Michael J. [Department of Soil, Water, and Climate and BioTechnology Institute, University of Minnesota, St. Paul, MN 55108 (United States); Kessel, Chris van; Six, Johan [Department of Plant Sciences, University of California - Davis, One Shields Avenue, Davis, CA 95616 (United States)

    2011-02-15

    We investigated the influence of elevated CO{sub 2} and O{sub 3} on soil N cycling within the soybean growing season and across soil environments (i.e., rhizosphere and bulk soil) at the Soybean Free Air Concentration Enrichment (SoyFACE) experiment in Illinois, USA. Elevated O{sub 3} decreased soil mineral N likely through a reduction in plant material input and increased denitrification, which was evidenced by the greater abundance of the denitrifier gene nosZ. Elevated CO{sub 2} did not alter the parameters evaluated and both elevated CO{sub 2} and O{sub 3} showed no interactive effects on nitrifier and denitrifier abundance, nor on total and mineral N concentrations. These results indicate that elevated CO{sub 2} may have limited effects on N transformations in soybean agroecosystems. However, elevated O{sub 3} can lead to a decrease in soil N availability in both bulk and rhizosphere soils, and this likely also affects ecosystem productivity by reducing the mineralization rates of plant-derived residues. - Graphical abstract: Research highlights: Elevated O{sub 3} promotes accumulation of total soil N. Ammonium concentrations under elevated O{sub 3} were lower than those under ambient conditions. Elevated O{sub 3} may increase mineral N losses through the increase of denitrification. Elevated CO{sub 2} did not affect soil mineral N and total N concentrations. - Our findings indicate that although elevated CO{sub 2} increases plant biomass, N transformations were minimally affected. In contrast, elevated O{sub 3} decreased soil mineral N likely through a reduction in plant material input and increased denitrification as indicated by the greater abundance of the denitrifier gene nosZ.

  11. Environmental and Physiographic Controls on Inter-Growing Season Variability of Carbon Dioxide and Water Vapour Fluxes in a Minerotrophic Fen

    Science.gov (United States)

    van der Kamp, G.; Sonnentag, O.; Chen, J. M.; Barr, A.; Hedstrom, N.; Granger, R.

    2008-12-01

    The interaction of fens with groundwater is spatially and temporally highly variable in response to meteorological conditions, resulting in frequent changes of groundwater fluxes in both vertical and lateral directions (flow reversals) across the mineral soil-peat boundary. However, despite the importance of the topographic and hydrogeological setting of fens, no study has been reported in the literature that explores a fen's atmospheric CO2 and energy flux densities under contrasting meteorological conditions in response to its physiographic setting. In our contribution we report four years of growing season eddy covariance and supporting measurements from the Canada Fluxnet-BERMS fen (formerly BOREAS southern peatland) in Saskatchewan, Canada. We first analyze hydrological data along two piezometer transects across the mineral soil-peat boundary with the objective of assessing changes in water table configuration and thus hydraulic gradients, indicating flow reversals, in response to dry and wet meteorological conditions. Next we quantify and compare growing season totals and diurnal and daily variations in evapotranspiration (ET) and net ecosystem exchange (NEE) and its component fluxes gross ecosystem productivity (GPP) and terrestrial ecosystem respiration (TER) to identify their controls with a major focus on water table depth. While ET growing season totals were similar (~ 310 mm) under dry and wet meteorological conditions, the CO2 sink- source strength of Sandhill fen varied substantially from carbon neutral (NEE = -2 [+-7] g C m-2 per growing season) under dry meteorological condition (2003) to a moderate CO2- sink with NEE ranging between 157 [+- 10] and 190 [+- 11] g C m-2 per growing season under wet meteorological conditions (2004, 2005, and 2006). Using a process-oriented ecosystem model, BEPS-TerrainLab, we investigate how different canopy components at Sandhill contribute to total ET and GPP, and thus water use efficiency, under dry and wet

  12. Climate change in winter versus the growing-season leads to different effects on soil microbial activity in northern hardwood forests

    Science.gov (United States)

    Sorensen, P. O.; Templer, P. H.; Finzi, A.

    2014-12-01

    Mean winter air temperatures have risen by approximately 2.5˚ C per decade over the last fifty years in the northeastern U.S., reducing the maximum depth of winter snowpack by approximately 26 cm over this period and the duration of winter snow cover by 3.6 to 4.2 days per decade. Forest soils in this region are projected to experience a greater number of freeze-thaw cycles and lower minimum winter soil temperatures as the depth and duration of winter snow cover declines in the next century. Climate change is likely to result not only in lower soil temperatures during winter, but also higher soil temperatures during the growing-season. We conducted two complementary experiments to determine how colder soils in winter and warmer soils in the growing-season affect microbial activity in hardwood forests at Harvard Forest, MA and Hubbard Brook Experimental Forest, NH. A combination of removing snow via shoveling and buried heating cables were used to induce freeze-thaw events during winter and to warm soils 5˚C above ambient temperatures during the growing-season. Increasing the depth and duration of soil frost via snow-removal resulted in short-term reductions in soil nitrogen (N) production via microbial proteolytic enzyme activity and net N mineralization following snowmelt, prior to tree leaf-out. Declining mass specific rates of carbon (C) and N mineralization associated with five years of snow removal at Hubbard Brook Experimental Forest may be an indication of microbial physiological adaptation to winter climate change. Freeze-thaw cycles during winter reduced microbial extracellular enzyme activity and the temperature sensitivity of microbial C and N mineralization during the growing-season, potentially offsetting nutrient and soil C losses due to soil warming in the growing-season. Our multiple experimental approaches show that winter climate change is likely to contribute to reduced microbial activity in northern hardwood forests.

  13. Model-based analysis of the influence of catchment properties on hydrologic partitioning across five mountain headwater subcatchments.

    Science.gov (United States)

    Kelleher, Christa; Wagener, Thorsten; McGlynn, Brian

    2015-06-01

    Ungauged headwater basins are an abundant part of the river network, but dominant influences on headwater hydrologic response remain difficult to predict. To address this gap, we investigated the ability of a physically based watershed model (the Distributed Hydrology-Soil-Vegetation Model) to represent controls on metrics of hydrologic partitioning across five adjacent headwater subcatchments. The five study subcatchments, located in Tenderfoot Creek Experimental Forest in central Montana, have similar climate but variable topography and vegetation distribution. This facilitated a comparative hydrology approach to interpret how parameters that influence partitioning, detected via global sensitivity analysis, differ across catchments. Model parameters were constrained a priori using existing regional information and expert knowledge. Influential parameters were compared to perceptions of catchment functioning and its variability across subcatchments. Despite between-catchment differences in topography and vegetation, hydrologic partitioning across all metrics and all subcatchments was sensitive to a similar subset of snow, vegetation, and soil parameters. Results also highlighted one subcatchment with low certainty in parameter sensitivity, indicating that the model poorly represented some complexities in this subcatchment likely because an important process is missing or poorly characterized in the mechanistic model. For use in other basins, this method can assess parameter sensitivities as a function of the specific ungauged system to which it is applied. Overall, this approach can be employed to identify dominant modeled controls on catchment response and their agreement with system understanding.

  14. Model‐based analysis of the influence of catchment properties on hydrologic partitioning across five mountain headwater subcatchments

    Science.gov (United States)

    Wagener, Thorsten; McGlynn, Brian

    2015-01-01

    Abstract Ungauged headwater basins are an abundant part of the river network, but dominant influences on headwater hydrologic response remain difficult to predict. To address this gap, we investigated the ability of a physically based watershed model (the Distributed Hydrology‐Soil‐Vegetation Model) to represent controls on metrics of hydrologic partitioning across five adjacent headwater subcatchments. The five study subcatchments, located in Tenderfoot Creek Experimental Forest in central Montana, have similar climate but variable topography and vegetation distribution. This facilitated a comparative hydrology approach to interpret how parameters that influence partitioning, detected via global sensitivity analysis, differ across catchments. Model parameters were constrained a priori using existing regional information and expert knowledge. Influential parameters were compared to perceptions of catchment functioning and its variability across subcatchments. Despite between‐catchment differences in topography and vegetation, hydrologic partitioning across all metrics and all subcatchments was sensitive to a similar subset of snow, vegetation, and soil parameters. Results also highlighted one subcatchment with low certainty in parameter sensitivity, indicating that the model poorly represented some complexities in this subcatchment likely because an important process is missing or poorly characterized in the mechanistic model. For use in other basins, this method can assess parameter sensitivities as a function of the specific ungauged system to which it is applied. Overall, this approach can be employed to identify dominant modeled controls on catchment response and their agreement with system understanding. PMID:27642197

  15. Plant phenological responses to a long-term experimental extension of growing season and soil warming in the tussock tundra of Alaska.

    Science.gov (United States)

    Khorsand Rosa, Roxaneh; Oberbauer, Steven F; Starr, Gregory; Parker La Puma, Inga; Pop, Eric; Ahlquist, Lorraine; Baldwin, Tracey

    2015-12-01

    Climate warming is strongly altering the timing of season initiation and season length in the Arctic. Phenological activities are among the most sensitive plant responses to climate change and have important effects at all levels within the ecosystem. We tested the effects of two experimental treatments, extended growing season via snow removal and extended growing season combined with soil warming, on plant phenology in tussock tundra in Alaska from 1995 through 2003. We specifically monitored the responses of eight species, representing four growth forms: (i) graminoids (Carex bigellowii and Eriophorum vaginatum); (ii) evergreen shrubs (Ledum palustre, Cassiope tetragona, and Vaccinium vitis-idaea); (iii) deciduous shrubs (Betula nana and Salix pulchra); and (iv) forbs (Polygonum bistorta). Our study answered three questions: (i) Do experimental treatments affect the timing of leaf bud break, flowering, and leaf senescence? (ii) Are responses to treatments species-specific and growth form-specific? and (iii) Which environmental factors best predict timing of phenophases? Treatment significantly affected the timing of all three phenophases, although the two experimental treatments did not differ from each other. While phenological events began earlier in the experimental plots relative to the controls, duration of phenophases did not increase. The evergreen shrub, Cassiope tetragona, did not respond to either experimental treatment. While the other species did respond to experimental treatments, the total active period for these species did not increase relative to the control. Air temperature was consistently the best predictor of phenology. Our results imply that some evergreen shrubs (i.e., C. tetragona) will not capitalize on earlier favorable growing conditions, putting them at a competitive disadvantage relative to phenotypically plastic deciduous shrubs. Our findings also suggest that an early onset of the growing season as a result of decreased snow cover

  16. Spatial-temporal variations in the thermal growing degree-days and season under climate warming in China during 1960-2011

    Science.gov (United States)

    Yin, Yunhe; Deng, Haoyu; Wu, Shaohong

    2017-10-01

    Vegetation growth and phenology are largely regulated by base temperature (T b) and thermal accumulation. Hence, the growing degree-days (GDD) and growing season (GS) calculated based on T b have primary effects on terrestrial ecosystems, and could be changed by the significant warming during the last century. By choosing 0, 5, and 10 °C, three key T b for vegetation growth, the GDD and GS in China during 1960-2011 were developed based on 536 meteorological stations with homogenized daily mean temperatures. Results show that both the GDD and GS showed positive sensitivity to the annual mean temperature. The start of the growing season (SOS) has advanced by 4.86-6.71 days, and the end of the growing season (EOS) has been delayed by 4.32-6.19 days, lengthening the GS by 10.76-11.02 days in China as a whole during 1960-2011, depending on the T b chosen. Consistently, the GDD has totally increased 218.92-339.40 °C days during the 52 years, with trends more pronounced in those based on a lower T b. The GDD increase was significant (Mann-Kendall test, p biological phenology, agricultural production, and terrestrial carbon cycle in the future.

  17. Are BVOC exchanges in agricultural ecosystems overestimated? Insights from fluxes measured in a maize field over a whole growing season

    Science.gov (United States)

    Bachy, Aurélie; Aubinet, Marc; Schoon, Niels; Amelynck, Crist; Bodson, Bernard; Moureaux, Christine; Heinesch, Bernard

    2016-04-01

    Maize is the most important C4 crop worldwide. It is also the second most important crop worldwide (C3 and C4 mixed), and is a dominant crop in some world regions. Therefore, it can potentially influence local climate and air quality through its exchanges of gases with the atmosphere. Among others, biogenic volatile organic compounds (BVOC) are known to influence the atmospheric composition and thereby modify greenhouse gases lifetime and pollutant formation in the atmosphere. However, so far, only two studies have dealt with BVOC exchanges from maize. Moreover, these studies were conducted on a limited range of meteorological and phenological conditions, so that the knowledge of BVOC exchanges by this crop remains poor. Here, we present the first BVOC measurement campaign performed at ecosystem-scale on a maize field during a whole growing season. It was carried out in the Lonzée Terrestrial Observatory (LTO), an ICOS site. BVOC fluxes were measured by the disjunct by mass-scanning eddy covariance technique with a proton transfer reaction mass spectrometer for BVOC mixing ratios measurements. Outstanding results are (i) BVOC exchanges from soil were as important as BVOC exchanges from maize itself; (ii) BVOC exchanges observed on our site were much lower than exchanges observed by other maize studies, even under normalized temperature and light conditions, (iii) they were also lower than those observed on other crops grown in Europe. Lastly (iv), BVOC exchanges observed on our site under standard environmental conditions, i.e., standard emission factors SEF, were much lower than those currently considered by BVOC exchange up-scaling models. From those observations, we deduced that (i) soil BVOC exchanges should be better understood and should be incorporated in terrestrial BVOC exchanges models, and that (ii) SEF for the C4 crop plant functional type cannot be evaluated at global scale but should be determined for each important agronomic and pedo-climatic region

  18. Spatial-temporal variations in the thermal growing degree-days and season under climate warming in China during 1960-2011.

    Science.gov (United States)

    Yin, Yunhe; Deng, Haoyu; Wu, Shaohong

    2017-10-02

    Vegetation growth and phenology are largely regulated by base temperature (T b) and thermal accumulation. Hence, the growing degree-days (GDD) and growing season (GS) calculated based on T b have primary effects on terrestrial ecosystems, and could be changed by the significant warming during the last century. By choosing 0, 5, and 10 °C, three key T b for vegetation growth, the GDD and GS in China during 1960-2011 were developed based on 536 meteorological stations with homogenized daily mean temperatures. Results show that both the GDD and GS showed positive sensitivity to the annual mean temperature. The start of the growing season (SOS) has advanced by 4.86-6.71 days, and the end of the growing season (EOS) has been delayed by 4.32-6.19 days, lengthening the GS by 10.76-11.02 days in China as a whole during 1960-2011, depending on the T b chosen. Consistently, the GDD has totally increased 218.92-339.40 °C days during the 52 years, with trends more pronounced in those based on a lower T b. The GDD increase was significant (Mann-Kendall test, p variation has a substantial acceleration mostly in 1987 or 1996, and a speed reduction or even a trend reversal in the early 2000s. Changes in the thermal growing degree-days and season are expected to have great implications for biological phenology, agricultural production, and terrestrial carbon cycle in the future.

  19. Forest Gaps Inhibit Foliar Litter Pb and Cd Release in Winter and Inhibit Pb and Cd Accumulation in Growing Season in an Alpine Forest.

    Directory of Open Access Journals (Sweden)

    Jie He

    Full Text Available The release of heavy metals (such as Pb and Cd from foliar litter play an important role in element cycling in alpine forest ecosystems. Although natural forest gaps could play important roles in the release of heavy metals from foliar litter by affecting the snow cover during the winter and solar irradiation during the growing season, few studies have examined these potential roles. The objectives of this study were to document changes in Pb and Cd dynamics during litter decomposition in the center of gaps and under closed canopies and to investigate the factors that controlled these changes during the winter and growing seasons.Senesced foliar litter from six dominant species, including Kangding willow (Salix paraplesia, Masters larch (Larix mastersiana, Mingjiang fir (Abies faxoniana, Alpine azalea (Rhododendron lapponicum, Red birch (Betula albosinensis and Mourning cypress (Sabina saltuaria, was placed in litterbags and incubated between the gap center and closed canopy conditions in an alpine forest in the eastern region of the Tibetan Plateau. The litterbags were sampled at the snow formation stage, snow coverage stage, snow melt stage and during the growing season. The Pb and Cd concentrations in the sampled foliar litter were determined by acid digestion (HNO3/HClO4.Over one year of decomposition, Pb accumulation and Cd release from the foliar litter occurred, regardless of the foliar litter species. However, Pb and Cd were both released from the foliar litter during the winter and accumulated during the growing season. Compared with the gap center and the canopy gap edge, the extended gap edge and the closed canopy showed higher Pb and Cd release rates in winter and higher Pb and Cd accumulation rates during the growing season, respectively. Statistical analyses indicate that the dynamics of Pb were significantly influenced by frequent freeze-thaw cycles in winter and appropriate hydrothermal conditions during the growing season, the

  20. [Seasonal rhythms of parathyroid hormone-related protein (PTHrP) expression in growing rats after functional mandibular protrusion].

    Science.gov (United States)

    Li, Jiang-Ning; Chen, Yang-Xi; Wang, Zheng-Rong

    2006-04-01

    To study parathyroid hormone-related protein (PTHrP) expression during forward mandibular positioning and compare it with the expression during natural growth in different seasons. Sixty-four SD rats were randomly divided into experimental and control groups. Each group were randomly divided into four groups according to seasons. Immunohistochemical (IHC) methods were used to test the protein expression of PTHrP. Macroscopic and microscopic approach were applied to analyze the results. PTHrP expressed in mandibular condylar cartilage (MCC), the expression was accelerated and enhanced when the mandible was positioned forward. Furthermore, there was a seasonal rhythm in the protein expression of PTHrP in both experimental and control groups. The protein expression in spring group rose more than other groups. The functional appliance therapy can enhance the protein expression of PTHrP. The enhancement has a seasonal rhythm, which indicates that for the functional treatment better results can be achieved in spring.

  1. Ten Years of Growing Season Water, Energy and Carbon Exchange From an Oil sands Reclamation Site, Fort McMurray, Alberta

    Science.gov (United States)

    Carey, S. K.; Drewitt, G. B.

    2013-12-01

    The oil sands mining industry in Canada has made a commitment to restore disturbed areas to an equivalent capability to that which existed prior to mining. Certification requires successful reclamation, which can in part be evaluated through long-term ecosystem studies. A reclamation site, informally named South Bison Hill (SBH) has had growing season water, energy and carbon fluxes measured via the eddy covariance method for 10 years since establishment. SBH was capped with a 0.2 m peat-glacial till mixture overlying 0.8 m of reworked glacial till soil. The site was seeded to barley cultivar (Hordeum spp.) in the summer of 2002 and later planted to white spruce (Picea glauca) and aspen (Populus spp.) in the summer/fall of 2004. Since 2007, the major species atop SBH has been aspen, and by 2012 was on average ~ 4 m in height. Climatically, mean growing temperature did not vary greatly, yet there was considerable difference in rainfall among years, with 2012 having the greatest rainfall at 321 mm, whereas 2011 and 2007 were notably dry at 180 and 178 mm, respectively. The partitioning of energy varied among years, but the fraction of latent heat as a portion of net radiation increased with the establishment of aspen, along with concomitant increases in LAI and growing season net ecosystem exchange (NEE). Peat growing season ET was smallest in 2004 at 2.3 mm/d and greatest in 2010 at ~3.9 mm/d. ET rates showed a marked increase in 2008 corresponding with the increase in LAI attributed to the aspen cover. Since the establishment of a surface cover and vegetation in 2003, SBH has been a growing season sink for carbon dioxide. Values of NEE follow similar patterns to those of ET, with values gradually becoming more negative (greater carbon uptake) as the aspen forest established. Comparison with other disturbed and undisturbed boreal aspen stands show that SBH exhibits similar water, energy and carbon flux patterns during the growing season.

  2. Effects of Repeated Growing Season Prescribed Fire on the Structure and Composition of Pine–Hardwood Forests in the Southeastern Piedmont, USA

    Directory of Open Access Journals (Sweden)

    Matthew J. Reilly

    2016-12-01

    Full Text Available We examined the effects of repeated growing season prescribed fire on the structure and composition of mixed pine–hardwood forests in the southeastern Piedmont region, Georgia, USA. Plots were burned two to four times over an eight-year period with low intensity surface fires during one of four six-week long periods from early April to mid-September. Density of saplings (0.25–11.6 cm diameter at breast height was significantly reduced after one or two fires during the first four-year period. Sapling density declined with additional burning over the next four years, but density of mesic hardwoods including sweetgum (Liquidambar styraciflua and red maple (Acer rubrum remained relatively high (~865 stems ha−1. Repeated burning had little effect on density or basal area of trees (≥11.7 cm dbh and changes in overstory structure were limited to small increases in the quadratic mean diameter of all trees and pines. We found little evidence to suggest differential effects on structure or composition due to timing of burn within the growing season. Although repeated growing season burning alters midstory structure and composition, burning alone is unlikely to result in immediate shifts in overstory composition or structure in mixed pine–hardwood forests of the southeastern Piedmont region.

  3. Spatiotemporal variations in growing season exchanges of CO2, H2O,and sensible heat in agricultural fields of the Southern GreatPlains

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Marc L.; Billesbach, David P.; Berry, Joseph A.; Riley,William J.; Torn, Margaret S.

    2007-06-13

    Climate, vegetation cover, and management create fine-scaleheterogeneity in unirrigated agricultural regions, with important but notwell-quantified consequences for spatial and temporal variations insurface CO2, water, and heat fluxes. We measured eddy covariance fluxesin seven agricultural fields--comprising winter wheat, pasture, andsorghum--in the U.S. Southern Great Plains (SGP) during the 2001-2003growing seasons. Land-cover was the dominant source of variation insurface fluxes, with 50-100 percent differences between fields planted inwinter-spring versus fields planted in summer. Interannual variation wasdriven mainly by precipitation, which varied more than two-fold betweenyears. Peak aboveground biomass and growing-season net ecosystem exchange(NEE) of CO2 increased in rough proportion to precipitation. Based on apartitioning of gross fluxes with a regression model, ecosystemrespiration increased linearly with gross primary production, but with anoffset that increased near the time of seed production. Because theregression model was designed for well-watered periods, it successfullyretrieved NEE and ecosystem parameters during the peak growing season,and identified periods of moisture limitation during the summer. Insummary, the effects of crop type, land management, and water limitationon carbon, water, and energy fluxes were large. Capturing the controllingfactors in landscape scale models will be necessary to estimate theecological feedbacks to climate and other environmental impactsassociated with changing human needs for agricultural production of food,fiber, and energy.

  4. Carbon, nitrogen and phosphorus storage across a growing season by the herbaceous layer in urban and preserved temperate hardwood forests

    Science.gov (United States)

    Michaeleen Gerken Golay; Janette Thompson; Randall Kolka; Kris Verheyen

    2016-01-01

    Question: Herbaceous plant communities in hardwood forests are important for maintaining biodiversity and associated ecosystem services, such as nutrient storage. Are there differences in herbaceous layer nutrient storage for urban park and state preserve forests, and is there seasonal variation? Location:...

  5. Seasonal variation of macro and trace mineral contents in 14 browse species that grow in northeastern Mexico.

    Science.gov (United States)

    Ramirez, R G.; Haenlein, G F.W.; Núñez-González, M A.

    2001-02-01

    Leaves and twigs from shrub species consumed by range goats: Acacia berlandieri, Acacia farnesiana, Acacia greggii, Acacia rigidula, Celtis pallida, Cercidium macrum, Condalia obovata, Cordia boissieri, Desmanthus virgathus, Leucaena leucocephala, Leucophyllum texanum, Opuntia lindehimieri, Porlieria angustifolia, Prosopis glandulosa, and Ziziphus obtusifolia were evaluated for comparative seasonal contents of Ca, P, Mg K, Zn, Mn, Cu and Fe. Plants were collected in summer (September 12, 1992), fall (November 20, 1992), winter (February 20, 1993) and spring (May 22, 1993) in Marín, County, Nuevo Leon, Mexico. During spring and summer mineral concentrations were higher in general. Only Ca, Mg, K, and Fe were in substantial amounts in all seasons to meet adult goat requirements. With the exception of spring, shrubs had extremely low P concentrations. Manganese, Cu and Zn in most plants had low marginal levels to meet adult goat requirements. Moreover, potential intake of P, Mn, Cu and Zn in shrub species by goats weighing 50kg BW consuming 2.0kg per day DM was low. However, plants such as D. virgathus, L. texanum, P. glandulosa, L. leucocephala and C. macrum can be considered prominent components in diets of range goats because of their high mineral concentrations. It appears that ration formulations for range goats in northeastern Mexico should include P, Mn, Cu and Zn in all seasons of the year.

  6. A GIS TOOL TO EVALUATE THE SPATIAL EVOLUTION OF HYDRO-THERMIC FEATURES DURING GROWING SEASON OF VEGETABLE CROPS IN ELBE RIVER LOWLAND (POLABI

    Directory of Open Access Journals (Sweden)

    VERA POTOP

    2012-11-01

    Full Text Available A GIS tool to evaluate the spatial evolution of hydro-thermic features during growing season of vegetable crops in Elbe River lowland (Polabi. This article presents the results of the first study on combined mezoclimatological, microclimatological and topographical tools for evaluating precision farming in the growth of vegetable crops in the Elbe River lowland (Polabi region from the Czech Republic. We assess the variability of basically climatological characteristics in relation to topographic characteristics at the regional (Polabi and local (agricultural farm scales. At regional scale, interpolation approach is based on local linear regression and universal kriging interpolation. At local scale, two conventional interpolation methods, spline and local ordinary kriging with a Gaussian model variance across the fields, were applied. The local spline interpolators have been used in developing digital elevation models (DEMs and to determine the slope angle inclination of vegetable fields. The DEMs of the vegetable crops fields was developed at a 10 m x 10 m resolution based on elevation data collected in the field by a hand-held RTK- Global Positioning System receiver. This tool allowed the distinction of microclimatic conditions that produce altitude-slope-related patterns of the spatial-temporal distribution of the basic meteorological elements during growing season of vegetable crops. The effect of slope on diurnal extreme temperatures in the vegetable cropped field conditions was more pronounced than that of elevation. Accordingly to developed maps, the warmest and longest duration of sunshine, and the least precipitation totals during growing season occurred in the middle part of Polabi.

  7. Phenology and species determine growing-season albedo increase at the altitudinal limit of shrub growth in the sub-Arctic.

    Science.gov (United States)

    Williamson, Scott N; Barrio, Isabel C; Hik, David S; Gamon, John A

    2016-11-01

    Arctic warming is resulting in reduced snow cover and increased shrub growth, both of which have been associated with altered land surface-atmospheric feedback processes involving sensible heat flux, ground heat flux and biogeochemical cycling. Using field measurements, we show that two common Arctic shrub species (Betula glandulosa and Salix pulchra), which are largely responsible for shrub encroachment in tundra, differed markedly in albedo and that albedo of both species increased as growing season progressed when measured at their altitudinal limit. A moveable apparatus was used to repeatedly measure albedo at six precise spots during the summer of 2012, and resampled in 2013. Contrary to the generally accepted view of shrub-covered areas having low albedo in tundra, full-canopy prostrate B. glandulosa had almost the highest albedo of all surfaces measured during the peak of the growing season. The higher midsummer albedo is also evident in localized MODIS albedo aggregated from 2000 to 2013, which displays a similar increase in growing-season albedo. Using our field measurements, we show the ensemble summer increase in tundra albedo counteracts the generalized effect of earlier spring snow melt on surface energy balance by approximately 40%. This summer increase in albedo, when viewed in absolute values, is as large as the difference between the forest and tundra transition. These results indicate that near future (albedo related to Arctic vegetation change are unlikely to be particularly large and might constitute a negative feedback to climate warming in certain circumstances. Future efforts to calculate energy budgets and a sensible heating feedback in the Arctic will require more detailed information about the relative abundance of different ground cover types, particularly shrub species and their respective growth forms and phenology. © 2016 John Wiley & Sons Ltd.

  8. Projections for the changes in growing season length of tree-ring formation on the Tibetan Plateau based on CMIP5 model simulations.

    Science.gov (United States)

    He, Minhui; Yang, Bao; Shishov, Vladimir; Rossi, Sergio; Bräuning, Achim; Ljungqvist, Fredrik Charpentier; Grießinger, Jussi

    2017-11-17

    The response of the growing season to the ongoing global warming has gained considerable attention. In particular, how and to which extent the growing season will change during this century is essential information for the Tibetan Plateau, where the observed warming trend has exceeded the global mean. In this study, the 1960-2014 mean length of the tree-ring growing season (LOS) on the Tibetan Plateau was derived from results of the Vaganov-Shashkin oscilloscope tree growth model, based on 20 composite study sites and more than 3000 trees. Bootstrap and partial correlations were used to evaluate the most significant climate factors determining the LOS in the study region. Based on this relationship, we predicted the future variability of the LOS under three emission scenarios (Representative Concentration Pathways (RCP) 2.6, 6.0, and 8.5, representing different concentrations of greenhouse gasses) derived from 17 Earth system models participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5). The averaged LOS on the Tibetan Plateau is 103 days during the period 1960-2014, and April-September minimum temperature is the strongest factor controlling the LOS. We detected a general increase in the LOS over the twenty-first century under all the three selected scenarios. By the middle of this century, LOS will extend by about 3 to 4 weeks under the RCPs 2.6 and 6.0, and by more than 1 month (37 days) under the RCP 8.5, relative to the baseline period 1960-2014. From the middle to the end of the twenty-first century, LOS will further extend by about 3 to 4 weeks under the RCPs 6.0 and 8.5, respectively. Under the RCP 2.6 scenario, however, the extension reaches a plateau at around 2050 and about 2 weeks LOS extension. In total, we found an average rate of 2.1, 3.6, and 5.0 days decade-1 for the LOS extension from 2015 to 2100 under the RCPs 2.6, 6.0, and 8.5, respectively. However, such estimated LOS extensions may be offset by other ecological

  9. Long-term enhanced winter soil frost alters growing season CO2 fluxes through its impact on vegetation development in a boreal peatland.

    Science.gov (United States)

    Zhao, Junbin; Peichl, Matthias; Nilsson, Mats B

    2017-08-01

    At high latitudes, winter climate change alters snow cover and, consequently, may cause a sustained change in soil frost dynamics. Altered winter soil conditions could influence the ecosystem exchange of carbon dioxide (CO2 ) and, in turn, provide feedbacks to ongoing climate change. To investigate the mechanisms that modify the peatland CO2 exchange in response to altered winter soil frost, we conducted a snow exclusion experiment to enhance winter soil frost and to evaluate its short-term (1-3 years) and long-term (11 years) effects on CO2 fluxes during subsequent growing seasons in a boreal peatland. In the first 3 years after initiating the treatment, no significant effects were observed on either gross primary production (GPP) or ecosystem respiration (ER). However, after 11 years, the temperature sensitivity of ER was reduced in the treatment plots relative to the control, resulting in an overall lower ER in the former. Furthermore, early growing season GPP was also lower in the treatment plots than in the controls during periods with photosynthetic photon flux density (PPFD) ≥800 μmol m-2  s-1 , corresponding to lower sedge leaf biomass in the treatment plots during the same period. During the peak growing season, a higher GPP was observed in the treatment plots under the low light condition (i.e. PPFD 400 μmol m-2  s-1 ) compared to the control. As Sphagnum moss maximizes photosynthesis at low light levels, this GPP difference between the plots may have been due to greater moss photosynthesis, as indicated by greater moss biomass production, in the treatment plots relative to the controls. Our study highlights the different responses to enhanced winter soil frost among plant functional types which regulate CO2 fluxes, suggesting that winter climate change could considerably alter the growing season CO2 exchange in boreal peatlands through its effect on vegetation development. © 2017 John Wiley & Sons Ltd.

  10. Projections for the changes in growing season length of tree-ring formation on the Tibetan Plateau based on CMIP5 model simulations

    Science.gov (United States)

    He, Minhui; Yang, Bao; Shishov, Vladimir; Rossi, Sergio; Bräuning, Achim; Ljungqvist, Fredrik Charpentier; Grießinger, Jussi

    2017-11-01

    The response of the growing season to the ongoing global warming has gained considerable attention. In particular, how and to which extent the growing season will change during this century is essential information for the Tibetan Plateau, where the observed warming trend has exceeded the global mean. In this study, the 1960-2014 mean length of the tree-ring growing season (LOS) on the Tibetan Plateau was derived from results of the Vaganov-Shashkin oscilloscope tree growth model, based on 20 composite study sites and more than 3000 trees. Bootstrap and partial correlations were used to evaluate the most significant climate factors determining the LOS in the study region. Based on this relationship, we predicted the future variability of the LOS under three emission scenarios (Representative Concentration Pathways (RCP) 2.6, 6.0, and 8.5, representing different concentrations of greenhouse gasses) derived from 17 Earth system models participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5). The averaged LOS on the Tibetan Plateau is 103 days during the period 1960-2014, and April-September minimum temperature is the strongest factor controlling the LOS. We detected a general increase in the LOS over the twenty-first century under all the three selected scenarios. By the middle of this century, LOS will extend by about 3 to 4 weeks under the RCPs 2.6 and 6.0, and by more than 1 month (37 days) under the RCP 8.5, relative to the baseline period 1960-2014. From the middle to the end of the twenty-first century, LOS will further extend by about 3 to 4 weeks under the RCPs 6.0 and 8.5, respectively. Under the RCP 2.6 scenario, however, the extension reaches a plateau at around 2050 and about 2 weeks LOS extension. In total, we found an average rate of 2.1, 3.6, and 5.0 days decade-1 for the LOS extension from 2015 to 2100 under the RCPs 2.6, 6.0, and 8.5, respectively. However, such estimated LOS extensions may be offset by other ecological factors that

  11. Environmental factors controlling forest evapotranspiration and surface conductance on a multi-temporal scale in growing seasons of a Siberian larch forest

    Science.gov (United States)

    Yoshida, Megumi; Ohta, Takeshi; Kotani, Ayumi; Maximov, Trofim

    2010-12-01

    SummaryThe water and energy fluxes in forests fluctuate on different temporal scales, reflecting the impact of environmental factors. We examined the temporal fluctuation of the turbulent fluxes, surface conductance ( Gs), and four environmental factors (photosynthetic photon flux density [ Q], vapour pressure deficit [ D], air temperature [ T], and volumetric soil water content [ θ]) in a Siberian larch forest, using wavelet power spectra. The responses of the latent heat flux ( λE) and Gs to the environmental factors were analysed using the wavelet scale-wise correlation coefficient (SWCC) on multiple temporal scales. The observation site is characterised by underlying permafrost and a relatively short growing season. Analysis was conducted from May to September in each of 8 years during 1998-2007. The relationships between Gs and the environmental factors were evaluated with restrictive functions of a Jarvis-type surface conductance model because Gs usually has non-linear relationships to ambient factors. According to the power spectra of each factor, the largest variation was seen on a diurnal timescale for λE, the sensible heat flux ( H), Gs, and Q, whereas D and T fluctuated from diurnal to inter-seasonal timescales, and θ varied significantly over periods longer than the inter-seasonal timescales. The SWCC indicated that λE and Gs respond differently to the same ambient factors due to their respective processes; namely, λE is affected by both atmospheric demand and land surface regulation, whereas Gs is affected only by the latter. λE correlated well with Q at all timescales, as well as with D and T on intra-seasonal to interannual scales and with θ on inter-seasonal to interannual timescales. The SWCC of Gs and Q showed two peaks, on diurnal and inter-seasonal to interannual timescales, reflecting the physiological processes of plants, and D affected Gs only on an intra-seasonal timescale, which is related to meteorological changes. T and

  12. Cherry tomatoes metabolic profile determined by ¹H-High Resolution-NMR spectroscopy as influenced by growing season.

    Science.gov (United States)

    Masetti, Olimpia; Ciampa, Alessandra; Nisini, Luigi; Valentini, Massimiliano; Sequi, Paolo; Dell'Abate, Maria Teresa

    2014-11-01

    The content of the most valuable metabolites present in the lipophilic fraction of Protected Geographical Indication cherry tomatoes produced in Pachino (Italy) was observed for 2 cultivated varieties, i.e. cv. Naomi and cv. Shiren, over a period of 3 years in order to observe variations due to relevant climatic parameters, e.g. solar radiation and average temperature, characterising different seasons. (1)H-NMR spectroscopy was applied and spectral data were processed by means of Principal Component Analysis (PCA). We found that the metabolic profile was different for the two considered cultivated varieties and they were differently affected by climatic conditions. Major metabolites influenced by cropping period were α-tocopherol and the unsaturated lipid fraction in Naomi cherry tomatoes, and chlorophylls and phospholipids in Shiren variety, respectively. These results furnished useful information on seasonal dynamics of such important nutritional metabolites contained in tomatoes, confirming also NMR spectroscopy as powerful tool to define a complete metabolic profiling. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Deconvolution of pigment and physiologically related photochemical reflectance index variability at the canopy scale over an entire growing season.

    Science.gov (United States)

    Hmimina, G; Merlier, E; Dufrêne, E; Soudani, K

    2015-08-01

    The sensitivity of the photochemical reflectance index (PRI) to leaf pigmentation and its impacts on its potential as a proxy for light-use efficiency (LUE) have recently been shown to be problematic at the leaf scale. Most leaf-to-leaf and seasonal variability can be explained by such a confounding effect. This study relies on the analysis of PRI light curves that were generated at the canopy scale under natural conditions to derive a precise deconvolution of pigment-related and physiologically related variability in the PRI. These sources of variability were explained by measured or estimated physiologically relevant variables, such as soil water content, that can be used as indicators of water availability and canopy chlorophyll content. The PRI mainly reflected the variability in the pigment content of the canopy. However, the corrected PRI, which was obtained by subtracting the pigment-related seasonal variability from the PRI measurement, was highly correlated with the upscaled LUE measurements. Moreover, the sensitivity of the PRI to the leaf pigment content may mask the PRI versus LUE relationship or result in an artificial relationship that reflects the relationship of chlorophyll versus LUE, depending on the species phenology. © 2015 John Wiley & Sons Ltd.

  14. The Growing Season, but Not the Farming System, Is a Food Safety Risk Determinant for Leafy Greens in the Mid-Atlantic Region of the United States

    Science.gov (United States)

    Marine, Sasha C.; Pagadala, Sivaranjani; Wang, Fei; Pahl, Donna M.; Melendez, Meredith V.; Kline, Wesley L.; Oni, Ruth A.; Walsh, Christopher S.; Everts, Kathryne L.; Buchanan, Robert L.

    2015-01-01

    Small- and medium-size farms in the mid-Atlantic region of the United States use varied agricultural practices to produce leafy greens during spring and fall, but the impact of preharvest practices on food safety risk remains unclear. To assess farm-level risk factors, bacterial indicators, Salmonella enterica, and Shiga toxin-producing Escherichia coli (STEC) from 32 organic and conventional farms were analyzed. A total of 577 leafy greens, irrigation water, compost, field soil, and pond sediment samples were collected. Salmonella was recovered from 2.2% of leafy greens (n = 369) and 7.7% of sediment (n = 13) samples. There was an association between Salmonella recovery and growing season (fall versus spring) (P = 0.006) but not farming system (organic or conventional) (P = 0.920) or region (P = 0.991). No STEC was isolated. In all, 10% of samples were positive for E. coli: 6% of leafy greens, 18% of irrigation water, 10% of soil, 38% of sediment, and 27% of compost samples. Farming system was not a significant factor for levels of E. coli or aerobic mesophiles on leafy greens but was a significant factor for total coliforms (TC) (P bacteria (P < 0.001), and end-of-line groundwater had marginally higher TC counts than source samples (P = 0.059). Overall, the data suggest that seasonal events, weather conditions, and proximity of compost piles might be important factors contributing to microbial contamination on farms growing leafy greens. PMID:25616798

  15. How does climate influence xylem morphogenesis over the growing season? Insights from long-term intra-ring anatomy in Picea abies.

    Science.gov (United States)

    Castagneri, Daniele; Fonti, Patrick; von Arx, Georg; Carrer, Marco

    2017-04-01

    During the growing season, the cambium of conifer trees produces successive rows of xylem cells, the tracheids, that sequentially pass through the phases of enlargement and secondary wall thickening before dying and becoming functional. Climate variability can strongly influence the kinetics of morphogenetic processes, eventually affecting tracheid shape and size. This study investigates xylem anatomical structure in the stem of Picea abies to retrospectively infer how, in the long term, climate affects the processes of cell enlargement and wall thickening. Tracheid anatomical traits related to the phases of enlargement (diameter) and wall thickening (wall thickness) were innovatively inspected at the intra-ring level on 87-year-long tree-ring series in Picea abies trees along a 900 m elevation gradient in the Italian Alps. Anatomical traits in ten successive tree-ring sectors were related to daily temperature and precipitation data using running correlations. Close to the altitudinal tree limit, low early-summer temperature negatively affected cell enlargement. At lower elevation, water availability in early summer was positively related to cell diameter. The timing of these relationships shifted forward by about 20 (high elevation) to 40 (low elevation) d from the first to the last tracheids in the ring. Cell wall thickening was affected by climate in a different period in the season. In particular, wall thickness of late-formed tracheids was strongly positively related to August-September temperature at high elevation. Morphogenesis of tracheids sequentially formed in the growing season is influenced by climate conditions in successive periods. The distinct climate impacts on cell enlargement and wall thickening indicate that different morphogenetic mechanisms are responsible for different tracheid traits. Our approach of long-term and high-resolution analysis of xylem anatomy can support and extend short-term xylogenesis observations, and increase our

  16. [Nitrous oxide emission, nitrification, denitrification and nitrogen mineralization during rice growing season in 2 soils from Uruguay].

    Science.gov (United States)

    Illarze, Gabriela; Del Pino, Amabelia; Riccetto, Sara; Irisarri, Pilar

    2017-09-23

    Microbial processes such as mineralization, nitrification and denitrification regulate nitrogen dynamics in the soil. The last two processes may produce nitrous oxide (N2O). In this work N2O fluxes were quantified at four moments of the rice cycle, sowing, tillering, panicle initiation and maturity, in two sites that differed mainly in their soil organic matter (OM) content, Salto (higher OM) and Treinta y Tres. Potential net N mineralization, ammonium oxidation and denitrification as well as the most probable numbers (MPN) of ammonia oxidizers and denitrifiers were determined. Potential N mineralization did not vary with the soil type and increased at rice maturity. Neither ammonia oxidation potential nor MPN were different among the soils. However, the soil with higher OM exhibited higher activity and MPN of denitrifiers, irrespective of the rice stage. In turn, at the latest phases of the crop, the MPN of denitrifiers increased coinciding with the highest mineralization potential and mineral N content of the soil. Significant differences in N2O flux were observed in Salto, where the highest emissions were detected at rice maturity, after the soil was drained (44.2 vs 20.8g N-N2O/ha d in Treinta y Tres). This work shows the importance of considering the soil type and end-of-season drainage of the rice field to elaborate GHGs (greenhouse gases) inventories. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  17. Effects of Corn Straw Returning and Nitrogen Fertilizer Application Methods on N2O Emission from Wheat Growing Season

    Directory of Open Access Journals (Sweden)

    XU Yu

    2015-12-01

    Full Text Available Based on a wheat field experiment, the effect of four treatments such as no-straw returning (SN, straw returning (SR, control release fertilizer application(SRC and nitrogen drilling(SRR on N2O emission was studied using the static chamber method and the gas chromatographic technique. The results indicated that the wheat field was the sources of N2O emission. The N2O emission peaks followed each time of fertilizer application and irrigation, and usually continued for 1~2 weeks. N2O emissions accounted for more than 40% of total emissions during the N2O emission peak. The amount of N2O emission during three growing stage of wheat from high to low was arranged in turn pre-wintering period, post-wintering period and wintering period. N2O emission could be increased by straw returning. Compared with SN, N2O emission could be enhanced by 48.6% under SR. Both SRC and SRR could decrease the N2O emission, increase wheat yield and economic benefit, especially the latter. Nitrogen drilling is a good method for yield increment and N2O abatement.

  18. Effect of corn dry distiller grains plus solubles supplementation level on performance and digestion characteristics of steers grazing native range during forage growing season.

    Science.gov (United States)

    Martínez-Pérez, M F; Calderón-Mendoza, D; Islas, A; Encinias, A M; Loya-Olguín, F; Soto-Navarro, S A

    2013-03-01

    Two experiments were conducted to evaluate effects of corn dry distiller grains plus condensed solubles (DDGS) supplementation level on performance digestion characteristics of steers grazing native range during the forage growing season. In the performance study, 72 (206 ± 23.6 kg; 2008) and 60 (230 ± 11.3 kg; 2009) English crossbred steer calves were used in a randomized complete block design replicated over 2 yr. The grazing periods lasted 56 and 58 d and started on August 11 and 18 for 2008 and 2009, respectively. Each year, steers were blocked by BW (light, medium, and heavy), stratified by BW within blocks, and randomly assigned to 1 of 4 grazing groups. Each grazing group (6 steers in 2008 and 5 in 2009) was assigned to a DDGS supplementation levels (0, 0.2, 0.4, and 0.6% BW). Grazing group served as the experimental unit with 12 groups per year receiving 1 of 4 treatments for 2 yr (n = 6). In the metabolism study, 16 English crossbred steers (360 ± 28.9 kg) fitted with ruminal cannulas grazing native range during the summer growing season were used in a completely randomized design to evaluate treatment effects on forage intake and digestion. The experiment was conducted during the first and second weeks of October 2008. Steers were randomly assigned to supplement level (0, 0.2, 0.4, and 0.6% BW; n = 4) and grazed a single native range pasture with supplements offered individually once daily at 0700 h. In the performance study, ADG (0.64, 0.75, 0.80, and 0.86 ± 0.03 kg/d for 0, 0.2, 0.4, and 0.6% BW, respectively) increased linearly (P = 0.01) with increasing DDGS supplementation level. In the metabolism study, forage OM, NDF, CP, and ether extract (EE) intake decreased (P ≤ 0.05) linearly with increasing DDGS supplementation level. Total CP and EE intake increased (P ≤ 0.002) with increasing DDGS supplementation level. Digestibility of OM, NDF, and EE increased (linear; P ≤ 0.008) whereas the soluble CP fraction of forage masticate sample

  19. Isoprene emissions from downy oak under water limitation during an entire growing season: what cost for growth?

    Directory of Open Access Journals (Sweden)

    Anne-Cyrielle Genard-Zielinski

    Full Text Available Increases in the production of terpene- and phenolic-like compounds in plant species under abiotic stress conditions have been interpreted in physiological studies as a supplementary defense system due to their capacity to limit cell oxidation. From an ecological perspective however, these increases are only expected to confer competitive advantages if they do not imply a significant cost for the plant, that is, growth reduction. We investigated shifts of isoprene emissions, and to a lesser extent phenolic compound concentration, of Quercus pubescens Willd. from early leaf development to leaf senescence under optimal watering (control: C, mild and severe water stress (MS, SS. The impact of water stress was concomitantly assessed on plant physiological (chlorophyll fluorescence, stomatal conductance, net photosynthesis, water potential functional (relative leaf water content, leaf mass per area ratio and growth (aerial and root biomass traits. Growth changes allowed to estimate the eventual costs related to the production of isoprene and phenolics. The total phenolic content was not modified under water stress whereas isoprene emissions were promoted under MS over the entire growing cycle despite the decline of Pn by 35%. Under SS, isoprene emissions remained similar to C all over the study despite the decline of Pn by 47% and were thereby clearly uncoupled to Pn leading to an overestimation of the isoprene emission factor by 44%. Under SS, maintenance of isoprene emissions and phenolic compound concentration resulted in very significant costs for the plants as growth rates were very significantly reduced. Under MS, increases of isoprene emission and maintenance of phenolic compound concentration resulted in moderate growth reduction. Hence, it is likely that investment in isoprene emissions confers Q. pubescens an important competitive advantage during moderate but not severe periods of water scarcity. Consequences of this response for air

  20. Hemato-biochemical and Cortisol Profile of Holstein Growing-calves Supplemented with Vitamin C during Summer Season

    Directory of Open Access Journals (Sweden)

    Jong-Hyeong Kim

    2012-03-01

    Full Text Available Effect of vitamin C (VC on biochemical, hematological and cortisol profile of growing Holstein calves during summer was investigated. Eighteen calves between 14 and 16 weeks of age were divided equally into two groups. One group received a diet supplemented with VC (20 g/d for 60 days, while other non-supplemented diet fed group served as a control (CON. The temperature humidity index (THI was recorded and computed during the experiment. From days 0 to 60, the THI exceeded 70. Blood samples were collected from the jugular vein of each calf at days 0, 15, 30, 45 and 60. Serum albumin and total protein decreased (p<0.05 in CON and VC calves with age. Serum glutamic-oxaloacetic transaminase concentrations were not affected by treatments. Serum creatinine, albumin and glutamic-pyruvic transaminase concentrations were higher in calves in the VC group than the CON group. While red blood cells, hemoglobin and hematocrit were lower (p<0.05 in VC calves, mean corpuscular volume, mean corpuscular hemoglobin, red blood cell distribution width and mean platelet volume were higher (p<0.05 in these VC supplemented calves. Leukocyte parameters including white blood cells and full term for lymphocytes were not affected by the treatments. Also, serum cortisol was not affected by treatments. At day 15, 30 and 45, the total VC in plasma was higher (p<0.05 in calves fed with VC. In conclusion, serum cortisols were not affected by plasma VC concentration, while some blood parameters were positively influenced in calves fed with VC.

  1. Productivity of a plantation of asparagus (Asparagus officinalis var. Altilis initiated green seedlings over four growing seasons

    Directory of Open Access Journals (Sweden)

    Castagnino, A.M.

    2014-01-01

    Full Text Available Although there are two initiation systems for an asparagus crop, i.e. by means of crowns and by means of seedlings, only the former allows the initiation of the definitive plantation in the first year. In order to determine the incidence of the seedling size throughout the first six years since planting, a trial was started on august 21, 2002, with three cell sizes: PG: big, PM: medium and PCH: small (70, 50 and 20 cm3 respectively and two densities: D1:35,714 and D2: 17,857 pl.ha-1, using the hybrid UC-157 and evaluating its productivity in the period 2005- 2008. Fresh weight per harvest (PFC and total annual fresh weight per ha (PFT, number of turions per harvest (NTC and per ha (NT and average weight per turion (PPT were determined. The PTF 2005-2008 was 26.300 Kg ha-1 and NT, with an annual average of 6,575 Kg ha-1 and 480,180 turions, respectively. NT showed a growing tendency throughout the whole period. Whereas, while the PFT grew in 2005-2007, it decreased in 2008 due to lower PPT, caused possibly by intra-specific competition. PM allowed a greater yield PFC: 343 Kg ha-1. The PPT turned out to be similar to that in 2005-2007, however it decreased in 2008. D1 obtained the maximum yield throughout the whole period. It can be concluded that when the aim is to obtain high initial productivity, it would be advisable to use seedlings of good size. Besides, the choice of density is an important factor due to the fact that there seems to be a direct relationship between the planting frame used and the obtained productivity.

  2. Modeling the impact of development and management options on future water resource use in the Nyangores sub-catchment of the Mara Basin in Kenya

    Science.gov (United States)

    Omonge, Paul; Herrnegger, Mathew; Fürst, Josef; Olang, Luke

    2016-04-01

    Despite the increasing water insecurity consequent of competing uses, the Nyangores sub-catchment of Kenya is yet to develop an inclusive water use and allocation plan for its water resource systems. As a step towards achieving this, this contribution employed the Water Evaluation and Planning (WEAP) system to evaluate selected policy based water development and management options for future planning purposes. Major water resources of the region were mapped and quantified to establish the current demand versus supply status. To define a reference scenario for subsequent model projections, additional data on urban and rural water consumption, water demand for crop types, daily water use for existing factories and industries were also collated through a rigorous fieldwork procedure. The model was calibrated using the parameter estimation tool (PEST) and validated against observed streamflow data, and subsequently used to simulate feasible management options. Due to lack of up-to-date data for the current year, the year 2000 was selected as the base year for the scenario simulations up to the year 2030, which has been set by the country for realizing most flagship development projects. From the results obtained, the current annual water demand within the sub-catchment is estimated to be around 27.2 million m3 of which 24% is being met through improved and protected water sources including springs, wells and boreholes, while 76% is met through informal and unprotected sources which are insufficient to cater for future increases in demand. Under the reference scenario, the WEAP model predicted an annual total inadequate supply of 8.1 million m3 mostly in the dry season by the year 2030. The current annual unmet water demand is 1.3 million m3 and is noteworthy in the dry seasons of December through February at the irrigation demand site. The monthly unmet domestic demand under High Population Growth (HPG) was projected to be 1.06 million m3 by the year 2030. However

  3. Effect of storage on the content of polyphenols of minimally processed skin-on apple wedges from ten cultivars and two growing seasons.

    Science.gov (United States)

    Rössle, Christian; Wijngaard, Hilde H; Gormley, Ronan T; Butler, Francis; Brunton, Nigel

    2010-02-10

    In this study, the polyphenolic composition of skin-on apple wedges from ten cultivars was examined during chill storage and over two growing seasons. Individual polyphenol compounds were measured using HPLC resulting in the total polyphenolic index (TPI). Total phenolic content (TPC) was quantified using the Folin-Ciocalteu assay. Chilled storage had a significant effect (P polyphenol composition of all ten cultivars grown in 2007 and 2008. Total phenolic indices (sum of individual polyphenols) and TPCs of nine of the ten cultivars significantly decreased (P apples over the same storage period. Changes in the most abundant compounds (-)-epicatechin, procyanidins and chlorogenic acid were largely responsible for changes in overall TPI. Percentage loss was higher for compounds such as phloridzin with a degradation of up to 100%. Irrespective of the different starting level of specific polyphenols in each year; storage resulted in a similar percentage loss/gain for each cultivar.

  4. Impacts of Short-Rotation Early-Growing Season Prescribed Fire on a Ground Nesting Bird in the Central Hardwoods Region of North America.

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    H Tyler Pittman

    Full Text Available Landscape-scale short-rotation early-growing season prescribed fire, hereafter prescribed fire, in upland hardwood forests represents a recent shift in management strategies across eastern upland forests. Not only does this strategy depart from dormant season to growing season prescriptions, but the strategy also moves from stand-scale to landscape-scale implementation (>1,000 ha. This being so, agencies are making considerable commitments in terms of time and resources to this management strategy, but the effects on wildlife in upland forests, especially those dominated by hardwood canopy species, are relatively unknown. We initiated our study to assess whether this management strategy affects eastern wild turkey reproductive ecology on the Ozark-St. Francis National Forest. We marked 67 wild turkey hens with Global Positioning System (GPS Platform Transmitting Terminals in 2012 and 2013 to document exposure to prescribed fire, and estimate daily nest survival, nest success, and nest-site selection. We estimated these reproductive parameters in forest units managed with prescribed fire (treated and units absent of prescribed fire (untreated. Of 60 initial nest attempts monitored, none were destroyed or exposed to prescribed fire because a majority of fires occurred early than a majority of the nesting activity. We found nest success was greater in untreated units than treated units (36.4% versus 14.6%. We did not find any habitat characteristic differences between successful and unsuccessful nest-sites. We found that nest-site selection criteria differed between treated and untreated units. Visual concealment and woody ground cover were common selection criteria in both treated and untreated units. However, in treated units wild turkey selected nest-sites with fewer small shrubs (20 cm DBH but not in untreated units. In untreated units wild turkey selected nest-sites with more large shrubs (≥5 cm ground diameter but did not select for small

  5. Testing the transferability of regression equations derived from small sub-catchments to a large area in central Sweden

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    C. Xu

    2003-01-01

    Full Text Available There is an ever increasing need to apply hydrological models to catchments where streamflow data are unavailable or to large geographical regions where calibration is not feasible. Estimation of model parameters from spatial physical data is the key issue in the development and application of hydrological models at various scales. To investigate the suitability of transferring the regression equations relating model parameters to physical characteristics developed from small sub-catchments to a large region for estimating model parameters, a conceptual snow and water balance model was optimised on all the sub-catchments in the region. A multiple regression analysis related model parameters to physical data for the catchments and the regression equations derived from the small sub-catchments were used to calculate regional parameter values for the large basin using spatially aggregated physical data. For the model tested, the results support the suitability of transferring the regression equations to the larger region. Keywords: water balance modelling,large scale, multiple regression, regionalisation

  6. Interactive Impacts of Nitrogen Input and Water Amendment on Growing Season Fluxes of CO2, CH4, and N2O in a Semiarid Grassland, Northern China

    Science.gov (United States)

    Zhang, L.

    2016-12-01

    Nitrogen and water are two primary limiting factors on the functioning of semiarid grasslands that play an important role on the climate system through land-atmosphere exchanges of greenhouse gases (GHG) (primarily CO2 - carbon dioxide; CH4 - methane, and N2O - nitrous oxide). However, the interactive effects of the nitrogen and water on GHG fluxes in semi-arid grasslands remain elusive. A 3-year (2010-2012) manipulative experiment in a semiarid grassland in Northern China was conducted to investigate the individual and interactive effects of nitrogen input and water amendment on GHG fluxes over growing seasons (May to September). Accumulated throughout one growing season, nitrogen input on average stimulated CO2 uptake by 3.3 ± 1.0 g C/m2/g N, enhanced N2O emission by 1.2 ± 0.3 mg N/m2/g N, and decreased CH4 uptake by 5.2 ± 0.9 mg C/m2/g N; water amendment stimulated CO2 uptake by 0.2 ± 0.1 g C/m2/mm H2O and N2O emission by 0.2 ± 0.02 mg N/m2/mm H2O, decreased CH4 uptake by 0.3 ± 0.1 mg C/m2/mm H2O. A synergistic effect between nitrogen and water additions was found on N2O flux in 2010 while the additive effects between nitrogen and water additions were found on CH4 and CO2 uptake during all experiment years, and on N2O emission in 2011 and 2012. The nitrogen addition had stronger impacts than water amendment on stimulating CH4 uptake in 2010 - the normal year, while water was the dominant factor affecting CH4 uptake in dry years. For N2O emission, the N-stimulating impact was stronger in un-watered than in watered plots, and water-stimulating impact was stronger in non-fertilized than in fertilized treatments in dry years. The mechanistic understanding of the interactive impacts of nitrogen and water additions on GHG fluxes obtained through this study provide valuable information for validating ecosystem models and understanding GHG fluxes in a multiple factors environment.

  7. Controls on plot-scale growing season CO2 and CH4 fluxes in restored peatlands: Do they differ from unrestored and natural sites?

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    M. Strack

    2016-06-01

    Full Text Available This study brings together plot-scale growing season fluxes of carbon dioxide (CO2 and methane (CH4 from six Canadian peatlands restored by the moss layer transfer technique (MLTT and compares them with fluxes from adjacent unrestored and natural peatlands to determine: 1 if CO2 and CH4 fluxes return to natural-site levels and 2 whether the ecohydrological controls (e.g. water table, plant cover on these fluxes are similar between treatments. We also examine differences between eastern (humid/maritime climate and western (sub-humid climate Canadian plots, and between restoration of former horticultural peat extraction sites and oil industry well-pads. Our results indicate that restored site fluxes of CO2 and CH4 are not significantly different between eastern and western Canada or between a restored well-pad and restored horticultural peat extraction sites. Restoration resulted in gross primary production rates similar to those at natural plots and significantly greater than those at unrestored plots. Ecosystem respiration was not significantly different at restored and unrestored plots, and was lower at both than at natural plots. Methane emission was significantly greater at restored plots than at unrestored plots, but remained significantly lower on average than at natural plots. Water table was a significant control on CH4 flux across restored and natural plots. Vascular plant cover was significantly related to CO2 uptake (gross photosynthesis at restored and unrestored plots, but not at natural plots, while higher moss cover resulted in significantly greater net uptake of CO2 at natural plots but not at restored and unrestored plots. Overall, MLTT restoration greatly alters CO2 and CH4 dynamics compared to unrestored areas but fluxes remain, on average, significantly different from those in natural peatlands, in both the magnitude of mean growing season fluxes and controls on variation in these fluxes among plots. Peatland restoration by

  8. Understanding flood risk sensitivity and uncertainty in a subcatchment of the Thames River (United Kingdom)

    Science.gov (United States)

    Theofanidi, Sofia; Cloke, Hannah Louise; Clark, Joanna

    2017-04-01

    of the flood events will follow, using simple hydrological boundary conditions. The sensitivity testing of the model, will permit to assess which parameters have the potential to alter significantly the peak discharge during the flood, flood water levels and flood inundation extent. Assessing the model's sensitivity and uncertainty, contributes to the improvement of the flood risk knowledge. The area of study is a subcatchment of the River Thames in the southern part of the United Kingdom. The Thames with its tributaries, support a wide range of social, economic and recreational activities. In addition, the historical and environmental importance of the Thames valley highlights the need for a sustainable flood mitigation planning which includes the better understanding of the flood mechanisms and flood risks.

  9. Projected changes of thermal growing season over Northern Eurasia in a 1.5 °C and 2 °C warming world

    Science.gov (United States)

    Zhou, Baiquan; Zhai, Panmao; Chen, Yang; Yu, Rong

    2018-03-01

    Projected changes of the thermal growing season (TGS) over Northern Eurasia at 1.5 °C and 2 °C global warming levels are investigated using 22 CMIP5 models under both RCP4.5 and RCP8.5 scenarios. The multi-model mean projections indicate Northern Eurasia will experience extended and intensified TGSs in a warmer world. The prolongation of TGSs under 1.5 °C and 2 °C warming is attributed to both earlier onset and later termination, with the latter factor playing a dominating role. Interestingly, earlier onset is of greater importance under RCP4.5 than under RCP8.5 in prolonging TGS as the world warms by an additional 0.5 °C. Under both RCPs, growing degree day sum (GDD) above 5 °C is anticipated to increase by 0 °C–450 °C days and 0 °C–650 °C days over Northern Eurasia at 1.5 °C and 2 °C warming, respectively. However, effective GDD (EGDD) which accumulates optimum temperature for the growth of wheat, exhibits a decline in the south of Central Asia under warmer climates. Therefore, for wheat production over Northern Eurasia, adverse effects incurred by scorching temperatures and resultant inadequacy in water availability may counteract benefits from lengthening and warming TGS. In response to a future 1.5 °C and 2 °C warmer world, proper management and scientifically-tailored adaptation are imperative to optimize local-regional agricultural production.

  10. Nonlinear advection-aridity method for landscape evaporation and its application during the growing season in the southern Loess Plateau of the Yellow River basin

    Science.gov (United States)

    Brutsaert, Wilfried; Li, Wei; Takahashi, Atsuhiro; Hiyama, Tetsuya; Zhang, Lu; Liu, Wenzhao

    2017-01-01

    The advection-aridity approach to estimate actual evaporation from natural land surfaces is one of the better known implementations of Bouchet's complementary principle. Detailed measurements at 2, 12, and 32 m above the ground surface during the growing seasons of 2004-2007 allowed validation of a generalized nonlinear form of this approach above the highly variable terrain in Changwu County in the southern Loess Plateau of the Yellow River basin in China. The obtained values of the parameters were found to lie well within the ranges to be expected on physical grounds or from previous measurements by different experimental means; calibration on the basis of any one year of data allowed predictions within roughly 5% on average. Relative to the corresponding observed turbulent vapor fluxes, the evaporation rates calculated with measurements at the highest level of 32 m displayed the least scatter but only slightly less than those calculated with measurements at the lower level of 12 m; however, those based on measurements at the lowest level of 2 m displayed considerably more scatter than those derived at the two higher levels. This is consistent with the existence of a blending height at higher elevations above the ground, where the effects of surface variability tend to fade away.

  11. Similarities and differences in occurrence and temporal fluctuations in glyphosate and atrazine in small Midwestern streams (USA) during the 2013 growing season

    Science.gov (United States)

    Mahler, Barbara J.; Van Metre, Peter C.; Burley, Thomas E.; Loftin, Keith A.; Meyer, Michael T.; Nowell, Lisa H.

    2017-01-01

    Glyphosate and atrazine are the most intensively used herbicides in the United States. Although there is abundant spatial and temporal information on atrazine occurrence at regional scales, there are far fewer data for glyphosate, and studies that compare the two herbicides are rare. We investigated temporal patterns in glyphosate and atrazine concentrations measured weekly during the 2013 growing season in 100 small streams in the Midwestern United States. Glyphosate was detected in 44% of samples (method reporting level 0.2 μg/L); atrazine was detected above a threshold of 0.2 μg/L in 54% of samples. Glyphosate was detected more frequently in 12 urban streams than in 88 agricultural streams, and at concentrations similar to those in streams with high agricultural land use (> 40% row crop) in the watershed. In contrast, atrazine was detected more frequently and at higher concentrations in agricultural streams than in urban streams. The maximum concentration of glyphosate measured at most urban sites exceeded the maximum atrazine concentration, whereas at agricultural sites the reverse was true. Measurement at a 2-day interval at 8 sites in northern Missouri revealed that transport of both herbicide compounds appeared to be controlled by spring flush, that peak concentration duration was brief, but that peaks in atrazine concentrations were of longer duration than those of glyphosate. The 2-day sampling also indicated that weekly sampling is unlikely to capture peak concentrations of glyphosate and atrazine.

  12. Growing season changes in Fennoscandia and Kola peninsula during the period 1982 to 1999 - Implications for reindeer husbandry (In Norwegian with Summary in English

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    Hans Tømmervik

    2005-04-01

    the length of the growing season in Fennoscandia and Kola Peninsula during the last two decades. We used phenological observation data for birch (Betula pubescens, and birch give a significant contribution to the reflectance from the ground in order to analyze the satellite data. A method using an individual threshold NDVI value for defining the onset of the growing season applied to each pixel for each year was chosen, and a high correlation was found between the NDVI data and in-situ phenological data on onset of leafing of birch. Determining the end of growing season based on a threshold NDVI value shows a lower correlation with surface data, but the timing by the set threshold is observed to measure somewhere in-between the onset of yellowing and all leaves fallen. In general, the results show a pattern according to vegetation zones and the altitude gradient, and partly according to vegetation sections. There are high regional differences in trends in the onset of spring. In the southern part of Fennoscandia, and on the oceanic west coast of Norway, the spring starts considerably earlier in the late nineties compared to the early eighties. The spring is stable or delayed in the northern boreal zone, which occupies large areas of northern Fennoscandia and Kola peninsula, and the same trend is also found in the alpine areas which occupies parts of both southern and northern Norway. The strongest delay occurred in the most continental section of the northern boreal zone. In the entire boreo-nemoral and nemoral zone, which occupy most of the southern part of Fennoscandia, the trend is opposite. In these areas the spring starts considerably earlier, in some parts several weeks. In the most oceanic section, the coastline of Western Norway, the spring also starts earlier. This earlier trend fits with the pattern from western and central Europe, and is likely to be related to increased spring temperature. At the same time the autumn is delayed in the whole area except in

  13. Growing season methane emission from a boreal peatland in the continuous permafrost zone of Northeast China: effects of active layer depth and vegetation

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    Y. Miao

    2012-11-01

    Full Text Available Boreal peatlands are significant natural sources of methane and especially vulnerable to abrupt climate change. However, the controlling factors of CH4 emission in boreal peatlands are still unclear. In this study, we investigated CH4 fluxes and abiotic factors (temperature, water table depth, active layer depth, and dissolved CH4 concentrations in pore water during the growing seasons in 2010 and 2011 in both shrub-sphagnum- and sedge-dominated plant communities in the continuous permafrost zone of Northeast China. The objective of our study was to examine the effects of vegetation types and abiotic factors on CH4 fluxes from a boreal peatland. In an Eriophorum-dominated community, mean CH4 emissions were 1.02 and 0.80 mg m−2 h−1 in 2010 and 2011, respectively. CH4 fluxes (0.38 mg m−2 h−1 released from the shrub-mosses-dominated community were lower than that from Eriophorum-dominated community. Moreover, in the Eriophorum-dominated community, CH4 fluxes showed a significant temporal pattern with a peak value in late August in both 2010 and 2011. However, no distinct seasonal variation was observed in the CH4 flux in the shrub-mosses-dominated community. Interestingly, in both Eriophorum- and shrub-sphagnum-dominated communities, CH4 fluxes did not show close correlation with air or soil temperature and water table depth, whereas CH4 emissions correlated well to active layer depth and CH4 concentration in soil pore water, especially in the Eriophorum-dominated community. Our results suggest that CH4 released from the thawed CH4-rich permafrost layer may be a key factor controlling CH4 emissions in boreal peatlands, and highlight that CH4 fluxes vary with vegetation type in boreal peatlands. With

  14. The Characterization of Extreme Episodes of Wet and Dry Deposition of Pollutants on an Above Cloud-Base Forest during its Growing Season.

    Science.gov (United States)

    Defelice, T. P.; Saxena, V. K.

    1991-11-01

    An analysis of a 3-yr database (1986-88) acquired new Mount Mitchell (35°4405N, 82°1715W, 2038 m MSL) where the forest consists primarily of Fraser fir and some red spruce stands is presented. The site was immersed in clouds for 28%-41% of the time during each of the three growing seasons (15 May-15 September). This study only investigated extreme episodes of wet (cloud-water pH% .3:1)and dry (eg., an ozone concentration 70 ppb) acidic deposition. Extreme wet events occasionally relieved periods of high ozone ( 70 ppb) exposures during the final field intensive. Extreme wet and dry events could activate the decline mechanism in any above cloud-base forest, especially if the trees are exposed to such events during very early or very late stages of their Lives. The exposure of the forest to natural climatic stress, such as drought condition wintertime temperatures during the growing season, snow storm during early spring, etc., would also subject the forest to a stressful period during which the exposure to the aforementioned episodes of pollutant deposition might trigger a decline.On the average, one of three cloud events that traverse this site is extreme. These extreme events usually last about 4 h. form during periods of high atmospheric pressure, have a liquid water content of 0.10 g m3, and contain cloud droplets of mean diameter around 8.0 m. During the dissipating stages, such cloud events result in maximum acidic deposition. When such events are preceded by very high ozone ( 100 ppb), they may prove oven more detrimental to forest health. A precipitating cloud event (pH = 4.4 on the average) preceded by periods of very high ozone concentrations will become an extreme episode. Extreme acidic events can occur in association with 1) an 850-mb closed low, situated just north of Montreal, Canada, that advances southward into New York State, and 2) an 850-mb high extending over the Gulf of Mexico (between Florida and Louisiana) to over eastern Kansas. In

  15. Fusarium species and fumonisins associated with maize kernels produced in Rio Grande do Sul State for the 2008/09 and 2009/10 growing seasons

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    R. Stumpf

    2013-01-01

    Full Text Available Ear rots caused by Fusarium spp. are among the main fungal diseases that contribute to poor quality and the contamination of maize grains with mycotoxins. This study aimed to determine the visual incidence of fungal-damaged kernels (FDKs, the incidence of two main Gibberella (a teleomorph of Fusarium complexes (G. fujikuroi and G. zeae associated with maize using a seed health blotter test, and the fumonisin levels, using high performance liquid chromatography, in samples of maize grains grown across 23 municipalities during the 2008/09 and 2009/10 growing seasons. Additionally, 104 strains that were representative of all of the analysed samples were identified to species using PCR assays. The mean FDK was seven per cent, and only six of the samples had levels greater than six per cent. Fusarium spp. of the G. fujikuroi complex were present in 96% of the samples, and G. zeae was present in 18% of the samples (5/27. The mean incidence of G. fujikuroi was 58%, and the incidence of G. zeae varied from 2 to 6%. FB1 was found in 58.6%, FB2 in 37.9%, and both toxins in 37.9% of the samples. The FB1 and FB2 levels were below the quantification limits for 41.3% of the samples, and the mean FB1 levels (0.66 µg/g were higher than the mean FB2 levels (0.42 µg/g. The PCR identification separated the 104 isolates into three of the G. fujikuroi complex: F. verticillioides (76%, F. subglutinans (4% and F. proliferatum (2%; and G. zeae (anamorph = F. graminearum (18%. Our results confirmed the dominance of F. verticillioides, similar to other regions of Brazil, but they differed due to the relatively higher incidence of F. graminearum. Total fumonisin levels were below the maximum limit determined by current Brazilian regulations.

  16. Passive Microwave Soil Moisture Retrieval Using a Ground-Based L-Band (1.26 GHz) Radiometer Acquired During the Corn Growing Season in 2002

    Science.gov (United States)

    Joseph, A. T.; van der Velde, R.; O'Neill, P. E.; Su, Z.; Liang, S.; Jackson, T. J.; Lang, R. H.; Kim, E. J.; Gish, T.

    2006-05-01

    In the corn growing season of 2002, a tower-based L-band (1.26 GHz) microwave radiometer (Lrad) and a truck-mounted C- and L-band (5.3 and 1.4 GHz) radar were installed and operated along the side of the corn grown OPE3* experimental site managed by the USDA-ARS** Hydrology and Remote Sensing Laboratory (HRSL) in Beltsville, Maryland. The radiometer was programmed to acquire data automatically every hour, while the radar observations were collected once a week at four different times during the day. The radiometer as well as the radar collected several individual observations within an azimuth of 120 degrees at various incidence angles (25, 35, 45, 55 and 60 for the radiometer and 15, 35 and 55 degrees for the radar). Simultaneous to the microwave observations, an extensive ground truth data set was collected, which includes soil moisture, soil surface roughness, vegetation moisture and vegetation geometry. In this investigation, soil moisture retrieval results are presented primarily based on the passive microwave OPE3 data set. The soil moisture retrieval algorithm is employed targeting the direct retrieval of the H (horizontal) - and V (vertical) - polarized optical depth from H- and V-polarized L-band brightness temperatures (TB). The methodology can be directly applied to observations that will be acquired by the Soil Moisture and Ocean Salinity (SMOS) sensor and requires only input of the temperature of the emitting layer, surface roughness and single scattering albedo. *Optimizing Production Inputs for Economic and Environmental Enhancement (OPE3) **United States Department of Agriculture (USDA) Agricultural Research Service (ARS)

  17. Sphagnum-dwelling testate amoebae in subarctic bogs are more sensitive to soil warming in the growing season than in winter: the results of eight-year field climate manipulations.

    Science.gov (United States)

    Tsyganov, Andrey N; Aerts, Rien; Nijs, Ivan; Cornelissen, Johannes H C; Beyens, Louis

    2012-05-01

    Sphagnum-dwelling testate amoebae are widely used in paleoclimate reconstructions as a proxy for climate-induced changes in bogs. However, the sensitivity of proxies to seasonal climate components is an important issue when interpreting proxy records. Here, we studied the effects of summer warming, winter snow addition solely and winter snow addition together with spring warming on testate amoeba assemblages after eight years of experimental field climate manipulations. All manipulations were accomplished using open top chambers in a dry blanket bog located in the sub-Arctic (Abisko, Sweden). We estimated sensitivity of abundance, diversity and assemblage structure of living and empty shell assemblages of testate amoebae in the living and decaying layers of Sphagnum. Our results show that, in a sub-arctic climate, testate amoebae are more sensitive to climate changes in the growing season than in winter. Summer warming reduced species richness and shifted assemblage composition towards predominance of xerophilous species for the living and empty shell assemblages in both layers. The higher soil temperatures during the growing season also decreased abundance of empty shells in both layers hinting at a possible increase in their decomposition rates. Thus, although possible effects of climate changes on preservation of empty shells should always be taken into account, species diversity and structure of testate amoeba assemblages in dry subarctic bogs are sensitive proxies for climatic changes during the growing season. Copyright © 2011 Elsevier GmbH. All rights reserved.

  18. Applicability of a “Multi-Stage Pulse Labeling” 15N Approach to Phenotype N Dynamics in Maize Plant Components during the Growing Season

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    Amanda de Oliveira Silva

    2017-08-01

    Full Text Available HighlightsThis work utilizes “multi-stage pulse labeling” 15N applications, primarily during reproductive growth stages, as a phenotyping strategy to identify maize hybrids with superior N use efficiency (NUE under low N conditions.Research using labeled isotopic N (15N can precisely quantify fertilizer nitrogen (N uptake and organ-specific N allocation in field crops such as maize (Zea mays L.. The overall research objective was to study plant N uptake patterns potentially correlated with N use efficiency (NUE in field-grown maize hybrids using a “multi-stage pulse labeling” 15N phenotyping strategy with an emphasis on the reproductive period. Five hybrids varying in NUE were compared under zero N fertilizer application (0N plus a moderate rate of 112 kg N ha−1 (112N in 2013 (2 locations and 2014 growing seasons. The equivalent of 3.2 (2013 to 2.1 (2014 kg of 15N ha−1, as labeled Ca(15NO32, was injected into soil on both sides of consecutive plants at multiple stages between V14 and R5. Aboveground plant biomass was primarily collected in short-term intervals (4–6 days after each 15N application in both years, and following a single long-term interval (at R6 after 15N injection at R1 in 2014. Averaged across hybrids and site-years, the moderate N rate (112N increased absolute 15N uptake at all stages; however, plants in the 0N treatment allocated proportionally more 15N to reproductive organs. Before flowering, short-term recovery of 15N (15Nrec totaled ~0.30 or 0.40 kg kg−1 of the 15N applied, and ~50% of that accumulated 15Nu was found in leaves and 40% in stems. After flowering, plant 15Nrec totaled ~0.30 kg kg−1 of 15N applied, and an average 30% of accumulated 15Nu was present in leaves, 17% in stems, and the remainder—usually the majority—in ears. At the R5 stage, despite a declining overall rate of 15N uptake per GDD thermal unit, plant 15Nrec represented ~0.25 kg kg−1 of 15N applied, of which ~65% was allocated

  19. The application Of Fourier Prediction Models To Schedule Paddy Growing Season With High Resolution For Upgrading Farm Capacity Building (Case Study in Indramayu Regency)

    Science.gov (United States)

    Martuani Siregar, Plato

    2016-08-01

    Indonesian government still has obstacles in the production of annual paddy harvest and planting which causes a decrease 20 percent drop in National production. The failure of one of them caused by weather patterns and climate change that makes farmers difficult to plan future activities with good crop calender. That is because the coming of the rainy season at this moment cannot be predicted precisely. To that end, the role of technology in model and estimate the precise rainfall (high resolution) becomes very important. The developing Fourier prediction models to become agriculture information system was user friendly for instructor/extension officers and farmers who can overcome this problem. The agriculture information models are developed to determine the time of crop calendar weighted maps with rice terraces whom government services, scout and farmers at Indramayu regency easily wears it. The sum of sinus models is used alternatively to predict deciles futures and monthly rainfalls for one year ahead produce a 0.97 correlation with the observed data in Indramayu region. The residue of the sum of sinus models became anomalous rainfall for instan ENSO can cause forward and late in rainfall season. Basically by using a method of curve fitting Sum of Sine results turned out to be related to the monsoon event and climate classification that indicate to distribute annual. While residue model shows cycles of 28.89,61.79 and 80.9 months. These frequencies are related to ENSO event. The Schmidt & Ferguson climate classification of rainfalls and wind monthly conclude Indramayu Regency dominate by type of wet and dry monthly. Map early in the season prediction and map early the planting of rice that have been tested since the start built 2008 is currently being updated with a system software, so that will make it easier for farmers and extension officers as well as related service to apply it on crop calendar.

  20. Effects of Urbanization and Seasonal Cycle on the Surface Urban Heat Island Patterns in the Coastal Growing Cities: A Case Study of Casablanca, Morocco

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    Hicham Bahi

    2016-10-01

    Full Text Available The urban heat island (UHI phenomenon is a harmful environmental problem in urban areas affecting both climatic and ecological processes. This paper aims to highlight and monitor the spatial distribution of Surface UHI (SUHI in the Casablanca region, Morocco, using remote sensing data. To achieve this goal, a time series of Landsat TM/ETM+/OLI-TIRS images was acquired from 1984 to 2016 and analyzed. In addition, nocturnal MODIS images acquired from 2005 to 2015 were used to evaluate the nighttime SUHI. In order to better analyze intense heat produced by urban core, SUHI intensity (SUHII was computed by quantifying the difference of land surface temperature (LST between urban and rural areas. The urban core SUHII appears more significant in winter seasons than during summer, while the pattern of SUHII becomes moderate during intermediate seasons. During winter, the average daytime SUHII gradually increased in the residential area of Casablanca and in some small peri-urban cities by more than 1 °C from 1984 to 2015. The industrial areas of the Casablanca region were affected by a significant rise in SUHII exceeding 15 °C in certain industrial localities. In contrast, daytime SUHII shows a reciprocal effect during summer with emergence of a heat island in rural areas and development of cool islands in urban and peri-urban areas. During nighttime, the SUHII remains positive in urban areas year-round with higher values in winter as compared to summer. The results point out that the seasonal cycle of daytime SUHII as observed in the Casablanca region is different from other mid-latitude cities, where the highest values are often observed in summer during the day.

  1. Spatio-temporal reconstruction of air temperature maps and their application to estimate rice growing season heat accumulation using multi-temporal MODIS data*

    Science.gov (United States)

    Zhang, Li-wen; Huang, Jing-feng; Guo, Rui-fang; Li, Xin-xing; Sun, Wen-bo; Wang, Xiu-zhen

    2013-01-01

    The accumulation of thermal time usually represents the local heat resources to drive crop growth. Maps of temperature-based agro-meteorological indices are commonly generated by the spatial interpolation of data collected from meteorological stations with coarse geographic continuity. To solve the critical problems of estimating air temperature (T a) and filling in missing pixels due to cloudy and low-quality images in growing degree days (GDDs) calculation from remotely sensed data, a novel spatio-temporal algorithm for T a estimation from Terra and Aqua moderate resolution imaging spectroradiometer (MODIS) data was proposed. This is a preliminary study to calculate heat accumulation, expressed in accumulative growing degree days (AGDDs) above 10 °C, from reconstructed T a based on MODIS land surface temperature (LST) data. The verification results of maximum T a, minimum T a, GDD, and AGDD from MODIS-derived data to meteorological calculation were all satisfied with high correlations over 0.01 significant levels. Overall, MODIS-derived AGDD was slightly underestimated with almost 10% relative error. However, the feasibility of employing AGDD anomaly maps to characterize the 2001–2010 spatio-temporal variability of heat accumulation and estimating the 2011 heat accumulation distribution using only MODIS data was finally demonstrated in the current paper. Our study may supply a novel way to calculate AGDD in heat-related study concerning crop growth monitoring, agricultural climatic regionalization, and agro-meteorological disaster detection at the regional scale. PMID:23365013

  2. Growing season CH4 and N2O fluxes from a subarctic landscape in northern Finland; from chamber to landscape scale

    Science.gov (United States)

    Dinsmore, Kerry J.; Drewer, Julia; Levy, Peter E.; George, Charles; Lohila, Annalea; Aurela, Mika; Skiba, Ute M.

    2017-02-01

    Subarctic and boreal emissions of CH4 are important contributors to the atmospheric greenhouse gas (GHG) balance and subsequently the global radiative forcing. Whilst N2O emissions may be lower, the much greater radiative forcing they produce justifies their inclusion in GHG studies. In addition to the quantification of flux magnitude, it is essential that we understand the drivers of emissions to be able to accurately predict climate-driven changes and potential feedback mechanisms. Hence this study aims to increase our understanding of what drives fluxes of CH4 and N2O in a subarctic forest/wetland landscape during peak summer conditions and into the shoulder season, exploring both spatial and temporal variability, and uses satellite-derived spectral data to extrapolate from chamber-scale fluxes to a 2 km × 2 km landscape area.From static chamber measurements made during summer and autumn campaigns in 2012 in the Sodankylä region of northern Finland, we concluded that wetlands represent a significant source of CH4 (3.35 ± 0.44 mg C m-2 h-1 during the summer campaign and 0.62 ± 0.09 mg C m-2 h-1 during the autumn campaign), whilst the surrounding forests represent a small sink (-0.06 ± weighted by forest/wetland proportion (0.99 ± 0.16, 0.93 ± 0.12 mg C m-2 h-1, respectively). Hence we conclude that ignoring the detailed spatial variability in CH4 emissions within a landscape leads to a potentially significant underestimation of landscape-scale fluxes. Given the small magnitude of measured N2O fluxes a similar level of detailed upscaling was not needed; we conclude that N2O fluxes do not currently comprise an important component of the landscape-scale GHG budget at this site.

  3. Impacts of climate change on drought: changes to drier conditions at the beginning of the crop growing season in southern Brazil

    Directory of Open Access Journals (Sweden)

    Vânia Rosa Pereira

    2017-12-01

    Full Text Available ABSTRACT The intensification of drought incidence is one of the most important threats of the 21st century with significant effects on food security. Accordingly, there is a need to improve the understanding of the regional impacts of climate change on this hazard. This study assessed long-term trends in probability-based drought indices (Standardized Precipitation Index and Standardized Evapotranspiration Index in the State of São Paulo, Brazil. Owing to the multi-scalar nature of both indices, the analyses were performed at 1 to 12-month time scales. The indices were calculated by means of a relativist approach that allowed us to compare drought conditions from different periods. The years 1961-1990 were used as the referential period. To the authors’ best knowledge, this is the first time that such relativist approach is used in historical trend analysis. The results suggest that the evapotranspiration rates have intensified the regional drought conditions. The time scale used to calculate the indices significantly affected the outcomes of drought trend assessments. The reason behind this feature is that the significant changes in the monthly regional patterns are limited to a specific period of the year. More specifically, virtually all significant changes have been observed during the first trimester of the rainy season (October, November and December. Considering that this period corresponds to critical plant growth stages (flowering/regrowth/sprouting of several major crops (e.g. Sugarcane and Citrus, we may conclude that these significant changes have increased the risk of crop yield reductions due to agricultural drought.

  4. Stakeholder discourse and water management - implementation of the participatory model CATCH in a Northern Italian alpine sub-catchment

    Science.gov (United States)

    Lupo Stanghellini, P. S.; Collentine, D.

    2008-03-01

    The Water Framework Directive (WFD, directive 2000/60/EC) was created to ensure the sustainable use of water resources in the European Union. A central guideline included throughout the directive is a call for the participation of stakeholders in the management of these resources. Involving stakeholders is an important step to ensure that catchment management plans take into consideration local experience in the development of these plans and the impact of the plans on local interests. This paper describes and analyses the results of a series of workshops to facilitate implementation of the WFD at a catchment level based on the stakeholder participation model, CATCH. To test the usefulness of the CATCH model, developed for water management in a catchment area, a sub-catchment in an alpine valley in the north-east of Italy, the Alta Valsugana in the Province of Trento, was chosen as the setting for a series of workshops. In this valley water is fundamental for activities associated with agriculture, domestic use, energy production, sports and recreation. In the recent past the valley has had serious problems related to water quality and quantity. Implementation of water management plans under the WFD may lead to conflicts within the catchment between different stakeholder interest groups. Including stakeholders in the development of management plans not only follows the guidelines of the WFD but also could result in a more locally adapted and acceptable plan for the catchment. A new stakeholder analysis methodology was developed and implemented in order to identify the relevant stakeholders of the area and then two sets of workshops involving the key stakeholders identified were conducted in Spring 2006. The CATCH meetings were a new experience for the participants, who had to deal with both the principles of the WFD in general and the participation requirement in particular. During the meetings, the CATCH model played a very important role in structuring the

  5. Assessing Wheat Frost Risk with the Support of GIS: An Approach Coupling a Growing Season Meteorological Index and a Hybrid Fuzzy Neural Network Model

    Directory of Open Access Journals (Sweden)

    Yaojie Yue

    2016-12-01

    Full Text Available Crop frost, one kind of agro-meteorological disaster, often causes significant loss to agriculture. Thus, evaluating the risk of wheat frost aids scientific response to such disasters, which will ultimately promote food security. Therefore, this paper aims to propose an integrated risk assessment model of wheat frost, based on meteorological data and a hybrid fuzzy neural network model, taking China as an example. With the support of a geographic information system (GIS, a comprehensive method was put forward. Firstly, threshold temperatures of wheat frost at three growth stages were proposed, referring to phenology in different wheat growing areas and the meteorological standard of Degree of Crop Frost Damage (QX/T 88-2008. Secondly, a vulnerability curve illustrating the relationship between frost hazard intensity and wheat yield loss was worked out using hybrid fuzzy neural network model. Finally, the wheat frost risk was assessed in China. Results show that our proposed threshold temperatures are more suitable than using 0 °C in revealing the spatial pattern of frost occurrence, and hybrid fuzzy neural network model can further improve the accuracy of the vulnerability curve of wheat subject to frost with limited historical hazard records. Both these advantages ensure the precision of wheat frost risk assessment. In China, frost widely distributes in 85.00% of the total winter wheat planting area, but mainly to the north of 35°N; the southern boundary of wheat frost has moved northward, potentially because of the warming climate. There is a significant trend that suggests high risk areas will enlarge and gradually expand to the south, with the risk levels increasing from a return period of 2 years to 20 years. Among all wheat frost risk levels, the regions with loss rate ranges from 35.00% to 45.00% account for the largest area proportion, ranging from 58.60% to 63.27%. We argue that for wheat and other frost-affected crops, it is

  6. Morpho-agronomic traits of common bean landraces in two growing seasonsCaracterísticas morfo-agronômicas de cultivares crioulas de feijão comum em dois anos de cultivo

    Directory of Open Access Journals (Sweden)

    Cileide Maria Medeiros Coelho

    2010-02-01

    Full Text Available The objective of this work was to characterize the genetic diversity of landrace beans in two years for morphologic and agronomy characteristics. Twenty four bean (Phaseolus vulgaris L. genotypes were evaluated during the growing seasons of 2006/2007 and 2007/2008, using the randomized block design with three replications in Lages - SC. The genotypes were analyzed for 12 morphological and agronomic traits. The genotypes were studied using multivariable techniques to measure genetic divergence represented by the generalized distance of Mahalanobis and the genotypes grouping was performed by Tocher's optimization procedure. Among the 12 variables evaluated, the weight of 100 seeds had the highest contribution in the separation of the genotypes followed by the pod length in the two seasons. Genotypes BAF 3, BAF 37, BAF 42, BAF 55, BAF 57 and BAF 75 had high grain yield (around 4,000 Kg ha-1 in the two growing seasons and they could be incorporated in the programs of genetic breeding or used in the crop production.O objetivo deste trabalho foi caracterizar a diversidade de genótipos crioulos de feijão em dois anos de cultivo quanto às características morfoagronômicas. O experimento foi conduzido com 24 genótipos nas safras de 2006/2007 e 2007/2008 no município de Lages - SC, sob delineamento experimental em blocos ao acaso com 3 repetições, em que foram avaliadas 12 características morfológicas e agronômicas. Foi utilizada a técnica de análise multivariada para medir a divergência genética representada pela distância generalizada de Mahalanobis e o agrupamento dos genótipos foi realizado através do método de otimização de Tocher. Entre as 12 características avaliadas, o peso de 100 sementes foi o caráter que apresentou maior contribuição na separação dos genótipos, seguido pelo comprimento da vagem, nos dois anos de cultivo. Os genótipos BAF 3, BAF 37, BAF 42, BAF 55, BAF 57 e BAF 75 apresentaram elevados níveis de

  7. Managing the impact of gold panning activities within the context of integrated water resources management planning in the Lower Manyame Sub-Catchment, Zambezi Basin, Zimbabwe

    Science.gov (United States)

    Zwane, Nonhlanhla; Love, David; Hoko, Zvikomborero; Shoko, Dennis

    Riverbed alluvial gold panning activities are a cause for degradation of river channels and banks as well as water resources, particularly through accelerated erosion and siltation, in many areas of Zimbabwe. The lower Manyame sub-catchment located in the Northern part of the country is one such area. This study analysed the implications of cross-sectoral coordination of the management of panning and its impacts. This is within the context of conflicts of interests and responsibilities. A situational analysis of different stakeholders from sectors that included mining, environment, water, local government and water users who were located next to identified panning sites, as well as panners was carried out. Selected sites along the Dande River were observed to assess the environmental effects. The study determined that all stakeholder groups perceived siltation and river bank degradation as the most severe effect of panning on water resources, yet there were divergent views with regards to coordination of panning management. The Water Act of 1998 does not give enough power to management institutions including the Lower Manyame Sub-catchment Council to protect water resources from the impacts of panning, despite the fact that the activities affect the water resource base. The Mines and Minerals Act of 1996 remains the most powerful legislation, while mining sector activities adversely affect environmental resources. Furthermore, complexities were caused by differences in the definition of water resources management boundaries as compared to the overall environmental resources management boundaries according to the Environmental Management Act (EMA) of 2000, and by separate yet parallel water and environmental planning processes. Environmental sector institutions according to the EMA are well linked to local government functions and resource management is administrative, enhancing efficient coordination.

  8. Filocrono em batateira afetado pelo tamanho do tubérculo-semente e pela época de cultivo Phyllocrono in potato affected by tuber-seed size and growing season

    Directory of Open Access Journals (Sweden)

    Nereu Augusto Streck

    2009-01-01

    Full Text Available O objetivo deste trabalho foi estimar o filocrono de plantas de batata da cultivar Asterix oriundas de diferentes tamanhos de tubérculos-semente, em duas épocas de cultivo em campo utilizando o conceito de graus-dia para o cálculo do filocrono. O experimento foi desenvolvido em Santa Maria (RS, na primavera de 2003 e no outono de 2004. Foram usados quatro tamanhos de tubérculos-semente da cultivar de batata Asterix: entre 2 e 4 cm, 4 e 6 cm, 6 e 8 cm e 8 e 10 cm. O filocrono (ºC dia folha-1 foi estimado pelo inverso do coeficiente angular da relação entre número de folhas na haste principal e a soma térmica calculada por três métodos: método 1 - considera apenas a temperatura base; método 2 - considera a temperatura base e a temperatura ótima, e método 3 - considera a temperatura base, a temperatura ótima e a temperatura máxima. O tamanho do tubérculo-semente não afetou o filocrono, mas o método de cálculo da soma térmica e a época de cultivo afetaram o filocrono da batateira cultivar Asterix. No método de cálculo da soma térmica a ser usado no filocrono da batateira cultivar Asterix, recomenda-se usar a temperatura base e a temperatura ótima, pois com este método, o filocrono foi similar entre as épocas de cultivo.The objective of this study was to estimate the phyllochron of the potato cultivar Asterix in plants derived from different tuber seed sizes in two field growing seasons using the concept of degrees-days for calculating the phyllochron. The experiment was conducted in Santa Maria, RS, during Spring 2003 and Fall 2004. Four classes of tuber-seed diameter of the potato cultivar Asterix were used: 2-4 cm, 4-6 cm, 6-8 cm and 8-10 cm. The phyllochron was estimated as the inverse of the slope of the linear regression of main stem leaves number against the thermal time calculated with three methods: method 1 - considering only the base temperature, method 2 - considering the base temperature and the optimum

  9. Growing Pains

    CERN Multimedia

    Katarina Anthony

    2013-01-01

    Heat expands and cold contracts: it’s a simple thermodynamic rule. But when temperatures swing from 300 K to near-absolute zero, this rule can mean a contraction of more than 80 metres across the LHC’s 27-km-long cryogenic system. Keeping this growth in check are compensators (a.k.a. bellows), which shrink and stretch in response to thermodynamic changes. Leak tests and X-rays now underway in the tunnel have revealed that these “joints” might be suffering from growing pains…   This 25-μm weld crack is thought to be the cause of the helium leaks. Prior to the LS1 warm-up, CERN’s cryogenic experts knew of two points in the machine’s cryogenic distribution system that were leaking helium. Fortunately, these leaks were sufficiently small, confined to known sub-sectors of the cryogenic line and – with help from the vacuum team (TE-VSC) – could easily be compensated for. But as the machine warmed up f...

  10. The influence of a semi-arid sub-catchment on suspended sediments in the Mara River, Kenya.

    Science.gov (United States)

    Dutton, Christopher L; Subalusky, Amanda L; Anisfeld, Shimon C; Njoroge, Laban; Rosi, Emma J; Post, David M

    2018-01-01

    The Mara River Basin in East Africa is a trans-boundary basin of international significance experiencing excessive levels of sediment loads. Sediment levels in this river are extremely high (turbidities as high as 6,000 NTU) and appear to be increasing over time. Large wildlife populations, unregulated livestock grazing, and agricultural land conversion are all potential factors increasing sediment loads in the semi-arid portion of the basin. The basin is well-known for its annual wildebeest (Connochaetes taurinus) migration of approximately 1.3 million individuals, but it also has a growing population of hippopotami (Hippopotamus amphibius), which reside within the river and may contribute to the flux of suspended sediments. We used in situ pressure transducers and turbidity sensors to quantify the sediment flux at two sites for the Mara River and investigate the origin of riverine suspended sediment. We found that the combined Middle Mara-Talek catchment, a relatively flat but semi-arid region with large populations of wildlife and domestic cattle, is responsible for 2/3 of the sediment flux. The sediment yield from the combined Middle Mara-Talek catchment is approximately the same as the headwaters, despite receiving less rainfall. There was high monthly variability in suspended sediment fluxes. Although hippopotamus pools are not a major source of suspended sediments under baseflow, they do contribute to short-term variability in suspended sediments. This research identified sources of suspended sediments in the Mara River and important regions of the catchment to target for conservation, and suggests hippopotami may influence riverine sediment dynamics.

  11. A retrospective assessment of gold mining in the Reedy Creek sub-catchment, northeast Victoria, Australia: residual mercury contamination 100 years later.

    Science.gov (United States)

    Churchill, R C; Meathrel, C E; Suter, P J

    2004-11-01

    The mining of gold can lead to toxic metals such as mercury (Hg) contaminating watercourses as by-products. The Reedy Creek sub-catchment, in northeast Victoria, Australia, was mined for gold in the 1850s. In 1998, samples were taken from six watercourses to measure any remaining toxic metal contamination in sediments and surface waters from two creeks with no previous gold mining (controls) and four that were mined. Although mean concentrations of Hg (measured using an ICP-OES) in sediments were below worldwide background levels, individual sites along Reedy Creek had slightly elevated Hg concentrations. In contrast, the Hg concentrations in the surface waters were above background levels. Temporal fluxes of very high Hg concentrations in the surface waters during periods of first flow and flood events revealed that Hg concentrations in the surface waters may, at certain times of the year, exceed all Australian and New Zealand Environment and Conservation Council (National Water Quality Management Strategy. Australian Water Quality Guidelines for Fresh and Marine Waters, ANZECC, 2000) guidelines for water use and the protection of the aquatic ecosystem. Copyright 2004 Elsevier Ltd.

  12. Simulating the Impact of Future Land Use and Climate Change on Soil Erosion and Deposition in the Mae Nam Nan Sub-Catchment, Thailand

    Directory of Open Access Journals (Sweden)

    Nitin Kumar Tripathi

    2013-07-01

    Full Text Available This paper evaluates the possible impacts of climate change and land use change and its combined effects on soil loss and net soil loss (erosion and deposition in the Mae Nam Nan sub-catchment, Thailand. Future climate from two general circulation models (GCMs and a regional circulation model (RCM consisting of HadCM3, NCAR CSSM3 and PRECIS RCM ware downscaled using a delta change approach. Cellular Automata/Markov (CA_Markov model was used to characterize future land use. Soil loss modeling using Revised Universal Soil Loss Equation (RUSLE and sedimentation modeling in Idrisi software were employed to estimate soil loss and net soil loss under direct impact (climate change, indirect impact (land use change and full range of impact (climate and land use change to generate results at a 10 year interval between 2020 and 2040. Results indicate that soil erosion and deposition increase or decrease, depending on which climate and land use scenarios are considered. The potential for climate change to increase soil loss rate, soil erosion and deposition in future periods was established, whereas considerable decreases in erosion are projected when land use is increased from baseline periods. The combined climate and land use change analysis revealed that land use planning could be adopted to mitigate soil erosion and deposition in the future, in conjunction with the projected direct impact of climate change.

  13. Composição físico-química de uvas para vinho fino em ciclos de verão e inverno Physico-chemical composition of wine grapes berries in summer and winter growing seasons

    Directory of Open Access Journals (Sweden)

    Renata Vieira da Mota

    2010-12-01

    Full Text Available Este trabalho teve como objetivo avaliar o potencial de maturação das cultivares Pinot Noir, Tempranillo, Merlot, Cabernet Sauvignon, Syrah, Chardonnay e Sauvignon Blanc submetidas ao regime de dupla poda, em Cordislândia, região cafeeira do sul de Minas Gerais. As plantas foram submetidas a dois ciclos de produção, um de primavera-verão, compreendido entre agosto e janeiro, e outro ciclo de outono-inverno, entre janeiro e julho. Como parâmetros de qualidade, foram avaliados os diâmetros transversal e longitudinal da baga, acidez, ácidos tartárico e málico, pH, sólidos solúveis, antocianinas, fenólicos totais e os teores de glicose, frutose e sacarose. Todas as variedades apresentaram maiores teores de pH, sólidos solúveis, açúcares, antocianinas e fenólicos totais, e redução nos diâmetros transversal e longitudinal na safra de inverno. A cultivar Syrah destacou-se das demais no conteúdo de antocianinas e fenólicos totais tanto no verão quanto no inverno, entretanto apresentou o menor conteúdo de açúcares. A alteração do ciclo de produção da videira através da técnica da dupla poda para colheita, no período de inverno, na região cafeeira de Minas Gerais, favorece a maturação dos frutos e melhora consideravelmente a qualidade das uvas para vinificação.This work aimed to evaluate some ripening parameters of cultivars Pinot Noir, Tempranillo, Merlot, Cabernet Sauvignon, Syrah, Chardonnay and Sauvignon Blanc submitted to the double-pruning management in Cordislândia, in the coffee region of the south of Minas Gerais State. Grapevines were cultivated in two different growing seasons, spring-summer from August to January and autumn-winter from January to July. Quality parameters such as berry transversal and longitudinal diameters, acidity, tartaric and malic acids, pH, soluble solids, anthocyanins, phenolic compounds, glucose, fructose and sucrose were evaluated. All cultivars showed higher pH, soluble solids

  14. Sugarcane crop efficiency in two growing seasons in São Paulo State, Brazil Eficiência da produção de cana-de-açúcar em duas safras no Estado de São Paulo

    Directory of Open Access Journals (Sweden)

    Fábio Ricardo Marin

    2008-11-01

    Full Text Available A conceptual framework for crop production efficiency was derived using thermodynamic efficiency concept, in order to generate a tool for performance evaluation of agricultural systems and to quantify the interference of determining factors on this performance. In Thermodynamics, efficiency is the ratio between the output and input of energy. To establish this relationship in agricultural systems, it was assumed that the input energy is represented by the attainable crop yield, as predicted through simulation models based on environmental variables. The method of FAO's agroecological zones was applied to the assessment of the attainable sugarcane yield, while Instituto Brasileiro de Geografia e Estatística (IBGE data were used as observed yield. Sugarcane efficiency production in São Paulo state was evaluated in two growing seasons, and its correlation with some physical factors that regulate production was calculated. A strong relationship was identified between crop production efficiency and soil aptitude. This allowed inferring the effect of agribusiness factors on crop production efficiency. The relationships between production efficiency and climatic variables were also quantified and indicated that solar radiation, annual rainfall, water deficiency, and maximum air temperature are the main factors affecting the sugarcane production efficiency.Um conceito de eficiência de produção agrícola foi derivado da Termodinâmica, para gerar um indicador para avaliação do desempenho de sistemas de produção agrícola e quantificação da interferência dos fatores determinantes desse desempenho. Em Termodinâmica, a eficiência de um processo é dada pela razão entre a energia recuperada e a energia utilizada. Para estabelecer essa relação em sistemas agrícolas, admitiu-se que a energia utilizada seja dada pela produtividade atingível, estimada por modelos de simulação desenvolvidos com base em variáveis ambientais. O método das

  15. Growing and Growing: Promoting Functional Thinking with Geometric Growing Patterns

    Science.gov (United States)

    Markworth, Kimberly A.

    2010-01-01

    Design research methodology is used in this study to develop an empirically-substantiated instruction theory about students' development of functional thinking in the context of geometric growing patterns. The two research questions are: (1) How does students' functional thinking develop in the context of geometric growing patterns? (2) What are…

  16. Pea (Pisum sativum) and faba bean (Vicia faba L.) seeds as protein sources in growing-finishing heavy pig diets: effect on growth performance, carcass characteristics and on fresh and seasoned Parma ham quality

    OpenAIRE

    Francesco Masoero; Carla Cerioli; Samantha Sigolo; Mauro Morlacchini; Aldo Prandini

    2011-01-01

    The effect of pea and faba bean inclusion in growing-finishing heavy pig diets was evaluated. The following iso-lysinic and iso-energetic diets offered to the pigs in three phases (40-80; 80-120; 120-160 kg) were compared: CTR, control diet with soybean meal (SBM) as protein source; RP, CTR diet where pea replaced SBM; RF, CTR diet where faba bean replaced SBM. 126 animals were randomly distributed in 3 homogeneous groups with 42 animals each (7 pens with 6 animals each per treatment). The RP...

  17. Growing media [Chapter 5

    Science.gov (United States)

    Douglass F. Jacobs; Thomas D. Landis; Tara Luna

    2009-01-01

    Selecting the proper growing medium is one of the most important considerations in nursery plant production. A growing medium can be defined as a substance through which roots grow and extract water and nutrients. In native plant nurseries, a growing medium can consist of native soil but is more commonly an "artificial soil" composed of materials such as peat...

  18. Suplementos múltiplos de auto controle de consumo na recria de novilhos no período das águas Multiple supplements of self controlled intake for steers during the growing phase in the rainy season

    Directory of Open Access Journals (Sweden)

    Joanis Tilemahos Zervoudakis

    2008-12-01

    Full Text Available Avaliou-se o uso de suplementos de autocontrole de consumo sobre o desempenho de 24 novilhos mestiços com idade e pesos médios iniciais de 12 meses e 172 kg, respectivamente, recriados em pastagem de Brachiaria decumbens Stapf. durante o período das águas, com disponibilidade média de 10,82 ton./ha. Forneceu-se sal mineral (SAL e suplementos à base de: uréia, mistura mineral, milho grão triturado e farelo de soja (MFS; uréia, mistura mineral, farelo de soja e farelo de glúten de milho (FGFS; e, uréia, mistura mineral, farelo de trigo e farelo de soja (FTFS, com teor protéico médio de 53,60% de PB. Não se verificou efeito da suplementação sobre os ganhos médios diários (P>0,05, que foram de: 0,820; 0,950; 1,020 e 0,970 kg/animal/dia, respectivamente, para SAL, MFS, FGFS e FTFS. Contudo, foram obtidos ganhos adicionais em torno de 20%, os quais são de grande relevância na intensificação da pecuária de ciclo curto em pastagens.Twenty four crossbred steers, with average initial age and weight of 12 months and 172 kg, respectively, grazing Brachiaria decumbens Stapf., in the rainy season (10.82 ton. Dry matter/ha, were used in the performance assay to evaluate the effect of supplements of self feed. Mineral salt (SAL and supplements based on: urea, mineral mix, grounded corn grain and soybean meal (MFS; urea, mineral mix, soybean meal and corn gluten meal (FGFS; and urea, mineral mix, wheat bran and soybean meal (FTFS, with average protein content of 53.60% CP, were fed. It was not observed effect (P>0.05 of supplementation on the average daily gain, of 0.820, 0.950, 1.020 and 0.970 kg/animal/day, respectively, for SAL, MFS, FGFS and FTFS. However, significant additional gains (20% were observed for supplemented steers.

  19. Pea (Pisum sativum and faba bean (Vicia faba L. seeds as protein sources in growing-finishing heavy pig diets: effect on growth performance, carcass characteristics and on fresh and seasoned Parma ham quality

    Directory of Open Access Journals (Sweden)

    Francesco Masoero

    2011-10-01

    Full Text Available The effect of pea and faba bean inclusion in growing-finishing heavy pig diets was evaluated. The following iso-lysinic and iso-energetic diets offered to the pigs in three phases (40-80; 80-120; 120-160 kg were compared: CTR, control diet with soybean meal (SBM as protein source; RP, CTR diet where pea replaced SBM; RF, CTR diet where faba bean replaced SBM. 126 animals were randomly distributed in 3 homogeneous groups with 42 animals each (7 pens with 6 animals each per treatment. The RP and RF diets did not negatively affect the carcass characteristics both of the pigs slaughtered at the conventional weight (127.5 kg and heavy pigs (158.5 kg. The pigs fed the RP and RF diets ate similarly to the pigs fed the CTR overall the trial but RF pigs grew better than CTR animals. The subcutaneous fat of the fresh hams destined for Parma ham production and obtained from pigs fed RP diet had a higher omega 3 fatty acid percentage. Moreover, the RP and RF diets resulted in fat with better omega 3/omega 6 ratio compared with CTR. All the fat samples had iodine numbers within the limit value (70 reported by the Production Disciplinary of Parma ham. No treatment effect was found on the analytical and sensorial characteristics of the Parma hams, except for the aged taste which was more intense in the hams obtained from pigs fed the RF diet. These results indicate that pea and faba bean may be used as an alternative to imported SBM.

  20. An Ambition to Grow

    OpenAIRE

    Ron Kemp; Hakkert, R.

    2006-01-01

    This report tries to gain insight in the willingness or ambition to grow of a small business owner. The main question of this report is therefore: Which factors influence the ambition to grow a business? To examine the ambition to grow an economic and a psychological perspective is given in this study.

  1. Protein and energy supplementation for growing steers, in dry season Suplementação proteica e energética para novilhos em recria, durante o período da seca

    Directory of Open Access Journals (Sweden)

    Dorismar David Alves

    2010-12-01

    Full Text Available Dry matter intake, ruminal pH and ammonia concentration of grazing growing steers during the dry period, receiving different supplementation levels, were evaluated. Five rumen fistulated steers, with 18 months of age, 322kg average body weight were used in a 5x5 Latin Square design. The treatments used were based on the daily supplement supply of 0 (control - without supplementation; 0.125; 0.25; 0.5 and 1.0% of body weight. The dry matter intake was determined by the relationship between the fecal dry matter excreted estimated with external (Cr2O3 and internal (iADF markers. The rumen fluid was sampled at 0, 3, 6 and 9 hours after feeding the supplement for pH and ammonia determination. The forage intake by the control group was of 4.81kg DM/day; equivalent at 0.244% of available forage. The reduction of forage intake was more evident for the supplementation level of 1.0% of BW (1.44 kg/day, without affecting the average daily gain of the animals. Ruminal pH was higher for control treatment, averaging 7.3. The smallest value observed was 6.38 for 1.0% of BW supplementation level. The ammonia nitrogen presented higher averages at 3 hours after supplementation for level 0.5% of BW (21.53 mg/dL. Protein supply and protein-energy supplementation does not reduce the total dry matter intake of animals, but dry matter intake of herbage.Avaliou-se a suplementação proteica e proteica energética no consumo de matéria seca e nos parâmetros ruminais (pH e N-NH3 de novilhos recriados a pasto, durante a seca. Foram utilizados cinco novilhos providos de cânulas ruminais, com 18 meses de idade e peso inicial de 322kg, distribuídos em esquema de quadrado latino 5x5. Os tratamentos utilizados foram 0,00 (controle; 0,125; 0,250; 0,500; 1,00% do peso vivo (PV de quantidade de suplementos. O consumo de matéria seca foi determinado por meio da relação entre a quantidade de matéria seca fecal excretada, com o uso de indicador externo (Cr2O3 e interno (FDAi

  2. Melting ice, growing trade?

    National Research Council Canada - National Science Library

    Sami Bensassi; Julienne C. Stroeve; Inmaculada Martínez-Zarzoso; Andrew P. Barrett

    2016-01-01

    Abstract Large reductions in Arctic sea ice, most notably in summer, coupled with growing interest in Arctic shipping and resource exploitation have renewed interest in the economic potential of the Northern Sea Route (NSR...

  3. Growing and energy conservation

    Science.gov (United States)

    Eric van Steenis

    2009-01-01

    As energy costs increase, resistance is strong to these costs becoming a larger proportion of production cost. Many options can be considered in this battle. This presentation deals only with altering thermostat settings during initial crop growth stages early in the season. Reducing energy requirements in greenhouse crop production while maintaining quality and on-...

  4. Quantifying uncertainty in the impacts of climate change on river discharge in sub-catchments of the Yangtze and Yellow River Basins, China

    Directory of Open Access Journals (Sweden)

    H. Xu

    2011-01-01

    Full Text Available Quantitative evaluations of the impacts of climate change on water resources are primarily constrained by uncertainty in climate projections from GCMs. In this study we assess uncertainty in the impacts of climate change on river discharge in two catchments of the Yangtze and Yellow River Basins that feature contrasting climate regimes (humid and semi-arid. Specifically we quantify uncertainty associated with GCM structure from a subset of CMIP3 AR4 GCMs (HadCM3, HadGEM1, CCSM3.0, IPSL, ECHAM5, CSIRO, CGCM3.1, SRES emissions scenarios (A1B, A2, B1, B2 and prescribed increases in global mean air temperature (1 °C to 6 °C. Climate projections, applied to semi-distributed hydrological models (SWAT 2005 in both catchments, indicate trends toward warmer and wetter conditions. For prescribed warming scenarios of 1 °C to 6 °C, linear increases in mean annual river discharge, relative to baseline (1961–1990, for the River Xiangxi and River Huangfuchuan are +9% and 11% per +1 °C respectively. Intra-annual changes include increases in flood (Q05 discharges for both rivers as well as a shift in the timing of flood discharges from summer to autumn and a rise (24 to 93% in dry season (Q95 discharge for the River Xiangxi. Differences in projections of mean annual river discharge between SRES emission scenarios using HadCM3 are comparatively minor for the River Xiangxi (13 to 17% rise from baseline but substantial (73 to 121% for the River Huangfuchuan. With one minor exception of a slight (−2% decrease in river discharge projected using HadGEM1 for the River Xiangxi, mean annual river discharge is projected to increase in both catchments under both the SRES A1B emission scenario and 2° rise in global mean air temperature using all AR4 GCMs on the CMIP3 subset. For the River Xiangxi, there is substantial uncertainty associated with GCM structure in the magnitude of the rise in flood (Q05 discharges (−1 to 41% under SRES A1B and −3 to 41% under 2

  5. Comportamento produtivo da videira 'Niagara Rosada' em diferentes sistemas de condução, com e sem cobertura plástica, durante as safras de inverno e de verão Evaluation of vertical and "y" training systems and overhead plastic cover on 'Niagara Rosada' grape yield, during summer and winter growing seasons

    Directory of Open Access Journals (Sweden)

    José Luiz Hernandes

    2013-03-01

    growing seasons: summer (2008 and 2009 and winter (2009 and 2010 showed that the Y shaped system allows obtaining higher yields and larger size of clusters when compared to the vertical trellis system. The plastic overhead cover on the Y shaped system increased yield and cluster weight. It was also found that yield and cluster weight were higher for the summer growing season when compared to the winter crop.

  6. Growing Plants and Minds

    Science.gov (United States)

    Presser, Ashley Lewis; Kamdar, Danae; Vidiksis, Regan; Goldstein, Marion; Dominguez, Ximena; Orr, Jillian

    2017-01-01

    Many preschool classrooms explore plant growth. However, because many plants take a long time to grow, it is often hard to facilitate engagement in some practices (i.e., since change is typically not observable from one day to another, children often forget their prior predictions or cannot recall what plants looked like days or weeks earlier).…

  7. Growing Up with "1984."

    Science.gov (United States)

    Franza, August

    1983-01-01

    Relates changing student reaction to George Orwell's "1984" over 20 years of teaching. Finds present high school students' acceptance of Orwell's bleak world vision both a sign of student honesty and a frightening indication of the growing reality of the book. (MM)

  8. Growing through Literature.

    Science.gov (United States)

    Thomas, Barbara J.

    "Growing through Literature" is a curriculum using Joan M. and Erik H. Erikson's theory of the Life Cycle as a structure for selecting and teaching literature to inner-city high school students at Brighton High School in Massachusetts. The program consists of four component parts: Journals, Selected Stories, Discussion, and…

  9. Growing Old in Exile

    DEFF Research Database (Denmark)

    Liversage, Anika; Mirdal, Gretty Mizrahi

    2017-01-01

    Some studies on immigrants and ageing focus on the question of return; others focus on how immigrants, who grow old in their countries of destination, ‘age in place’, including whether they turn to their children or to public host country provisions for care and support. However, the issues of re...

  10. Desempenho de novilhos em crescimento em pastagem de Brachiaria decumbens suplementados com diferentes fontes energéticas no período da seca e transição seca-águas Development of growing steers on Brachiaria decumbens supplemented with different energy sources during the dry season and transition from dry to wet season

    Directory of Open Access Journals (Sweden)

    Jocilaine Garcia

    2004-12-01

    Full Text Available Objetivou-se, neste trabalho, estudar o efeito da suplementação, com diferentes fontes energéticas, sobre o desempenho de novilhos em crescimento e a viabilidade econômica da suplementação, bem como avaliar a disponibilidade e composição química da braquiária (Brachiaria decumbens Stapf, no período de julho a novembro, na região Oeste do Estado de São Paulo. Foram utilizados 42 novilhos da raça Nelore, distribuídos em três piquetes de 7,2 ha cada. As fontes energéticas utilizadas como suplementos foram: milho desintegrado com palha e sabugo (MDPS, farinha de mandioca de varredura (FMV e casca do grão de soja (CGS. Todos os tratamentos continham farelo de algodão, para atingir 25% de PB, e foram fornecidos em nível de 1,3% do PV. As pesagens dos animais foram realizadas a cada 14 dias e a disponibilidade de forragem foi estimada a cada 28 dias. A disponibilidade média de forragem foi de 2.570 kg de MS/ha e 1.306 kg de lâmina foliar/ha. A proporção de lâmina foliar apresentou comportamento quadrático em função do período experimental, com valor mínimo de 46,58%, observado em agosto. Os teores médios de proteína bruta foram de: 4,45% para planta inteira; 5,30% para lâmina foliar e 2,83% para o colmo + bainha. Os teores médios de FDN e FDA foram, respectivamente, de 70,61% e 39,93% para a planta inteira; 65,76% e 34,91% para a lâmina foliar e 75,83% e 47,90% para o colmo + bainha. Entre os suplementos não houve diferença para ganho médio diário, apresentando média de 0,836 kg/animal/dia. O suplemento mais viável economicamente foi o que continha a farinha de mandioca de varredura, pois, além de apresentar menor custo, foi o que proporcionou maior ganho animal, mostrando melhor relação receita: custo.The aim of this work was evaluate the effect of supplementation with different energetic sources, on growing steers performance and economical viability, and also evaluate the structure and chemical composition

  11. Managing Your Seasonal Allergies

    Science.gov (United States)

    ... page please turn JavaScript on. Feature: Seasonal Allergies Managing Your Seasonal Allergies Past Issues / Spring 2015 Table ... decongestants, or immunotherapy. Read More "Seasonal Allergies" Articles Managing Your Seasonal Allergies / Diagnosis, Treatment & Research Spring 2015 ...

  12. Adubação orgânica da batata com esterco e, ou, Crotalaria juncea: II - disponibilidade de N, P e K no solo ao longo do ciclo de cultivo Organic fertilization of potato with manure and, or, Crotalaria juncea: II - soil N, P, and K availability throughout the growing season

    Directory of Open Access Journals (Sweden)

    Tácio Oliveira da Silva

    2007-02-01

    imobilização de N do solo nas primeiras semanas. O tratamento C aumentou o teor de N mineral do solo no período imediatamente após a incorporação, mas não aumentou o teor de P e K extraíveis. No ensaio em casa de vegetação, o capim-buffel acumulou mais biomassa aérea e nutrientes no primeiro corte, 35 dias após o transplantio do capim, no solo do tratamento CE. Nos cortes subseqüentes, o tratamento E levou à maior produção de biomassa e acumulação de nutrientes, indicando que a limitação de N no período inicial após a incorporação de esterco ao solo prejudicou o crescimento do buffel. Os resultados corroboram a hipótese de que o plantio e incorporação da crotalária, combinado com a aplicação de apenas a metade da dose usual de esterco caprino, promoveu mineralização de nutrientes mais sincronizada com as necessidades das culturas agrícolas, pois foi capaz de evitar a imobilização de N do solo no período inicial de cultivo e elevou os teores de P e K disponíveis ao longo de todo o período.Soil fertility levels in the Agreste region, state of Paraíba, Brazil are generally low. Usually, animal manure is applied to soils to supply agricultural crops with nutrients. However, depending on the quality of the manure applied, incorporation can lead to soil nitrogen immobilization in the beginning of the growing season. It was hypothesized that planting and incorporating crotalaria (Crotalaria juncea together with animal manure could synchronize the nutrient mineralization pattern more specifically with crop demand. In 2003, field and green-house experiments were carried out to test this hypothesis. Prior to the current study, the field plots were cultivated with potato from 1996 to 2002 and subjected annually to the following organic fertilization treatments: planting and incorporation of crotalaria during flowering (C; manure incorporation, 15 t ha-1 (E; planting and incorporation of crotalaria + 7.5 t ha-1 manure (CE; and control plots (T

  13. Growing unculturable bacteria.

    Science.gov (United States)

    Stewart, Eric J

    2012-08-01

    The bacteria that can be grown in the laboratory are only a small fraction of the total diversity that exists in nature. At all levels of bacterial phylogeny, uncultured clades that do not grow on standard media are playing critical roles in cycling carbon, nitrogen, and other elements, synthesizing novel natural products, and impacting the surrounding organisms and environment. While molecular techniques, such as metagenomic sequencing, can provide some information independent of our ability to culture these organisms, it is essentially impossible to learn new gene and pathway functions from pure sequence data. A true understanding of the physiology of these bacteria and their roles in ecology, host health, and natural product production requires their cultivation in the laboratory. Recent advances in growing these species include coculture with other bacteria, recreating the environment in the laboratory, and combining these approaches with microcultivation technology to increase throughput and access rare species. These studies are unraveling the molecular mechanisms of unculturability and are identifying growth factors that promote the growth of previously unculturable organisms. This minireview summarizes the recent discoveries in this area and discusses the potential future of the field.

  14. Impacts of land use and population density on seasonal surface water quality using a modified geographically weighted regression.

    Science.gov (United States)

    Chen, Qiang; Mei, Kun; Dahlgren, Randy A; Wang, Ting; Gong, Jian; Zhang, Minghua

    2016-12-01

    As an important regulator of pollutants in overland flow and interflow, land use has become an essential research component for determining the relationships between surface water quality and pollution sources. This study investigated the use of ordinary least squares (OLS) and geographically weighted regression (GWR) models to identify the impact of land use and population density on surface water quality in the Wen-Rui Tang River watershed of eastern China. A manual variable excluding-selecting method was explored to resolve multicollinearity issues. Standard regression coefficient analysis coupled with cluster analysis was introduced to determine which variable had the greatest influence on water quality. Results showed that: (1) Impact of land use on water quality varied with spatial and seasonal scales. Both positive and negative effects for certain land-use indicators were found in different subcatchments. (2) Urban land was the dominant factor influencing N, P and chemical oxygen demand (COD) in highly urbanized regions, but the relationship was weak as the pollutants were mainly from point sources. Agricultural land was the primary factor influencing N and P in suburban and rural areas; the relationship was strong as the pollutants were mainly from agricultural surface runoff. Subcatchments located in suburban areas were identified with urban land as the primary influencing factor during the wet season while agricultural land was identified as a more prevalent influencing factor during the dry season. (3) Adjusted R 2 values in OLS models using the manual variable excluding-selecting method averaged 14.3% higher than using stepwise multiple linear regressions. However, the corresponding GWR models had adjusted R 2 ~59.2% higher than the optimal OLS models, confirming that GWR models demonstrated better prediction accuracy. Based on our findings, water resource protection policies should consider site-specific land-use conditions within each watershed to

  15. Dissolved organic matter (DOM) export to a temperate estuary: Seasonal variations and implications of land use

    DEFF Research Database (Denmark)

    Stedmon, C. A.; Markager, S.; Søndergaard, M.

    2006-01-01

    Inputs of dissolved carbon, nitrogen, and phosphorus were assessed for an estuary and its catchment (Horsens, Denmark). Seasonal patterns in the concentrations of DOM in the freshwater supply to the estuary differed depending on the soil and drainage characteristics of the area. In streams draining......, and the percentage of catchment area used for agriculture. Colored DOM (CDOM) loading measurements were found to be a good predictor of dissolved organic carbon (DOC) loading across the different subcatchments, offering a rapid and inexpensive alternative of operationally monitoring DOC export. For all the dissolved...... nutrient inputs to the estuary, dissolved inorganic nitrogen (DIN) and dissolved organic phosphorus dominated the loadings. Although 81% of the nitrogen annually supplied to the estuary was DIN, 83% of the nitrogen exported from the estuary was dissolved organic nitrogen (DON). Results show that increasing...

  16. Associação de diferentes fontes energéticas e protéicas em suplementos múltiplos na recria de novilhos mestiços sob pastejo no período da seca Association of different energy and protein sources in multiple supplements fed to growing crossbreed bulls at pasture in the dry season

    Directory of Open Access Journals (Sweden)

    Eduardo Henrique Bevitori Kling de Moraes

    2006-06-01

    seca, pois correspondem a aproximadamente 80% de sua composição. Observaram-se variações entre as frações dos carboidratos, assim como na taxa de degradação das fontes energéticas e protéicas estudadas.Two trials were conducted to investigate different protein and energy sources in multiple supplements fed to growing crossbred bulls. In the first experiment, performance of 20 crossbred growing bulls averaging 17 months of age and 265±18 kg of body weight was evaluated in the dry season. Animals were maintained in 1.5 ha paddocks of Brachiaria brizantha with supplements being offered daily in a proportion of 0.75% of the body weight. A completely randomized design with a 2 x 2 factorial arrangement was used. Supplements contained whole soybean (WSB or whole cottonseed (WCS as the protein sources and rice bran (RB or wheat bran (WB as the energy sources. No significant differences on the average daily weight gain (ADG, final body weight (FBW, and total weight gain were observed among diets in this trial. The ADG and FBW averaged 0.589 and 318.2, 0.530 and 317.2, 0.620 and 319.6 and 0.606 kg/day and 323.6 kg for animals fed supplements containing WSB/WB, WSB/RB, WCS/WB, and WCS/RB, respectively. The objective of the second study was to estimate the carbohydrate fractions of the pasture and that of the feeds used in multiple supplements as well as their digestion rates using the gas production technique. Forage had higher indigestible fraction (C and lower potentially degradable fraction (B2 compared to the supplements. Among supplements, WCS had the lowest C fraction while WSB and WB had the highest proportion of non-fiber carbohydrates (NFC. Although WCS had the highest content of C fraction, it also showed the fastest rate of digestion of the B2 fraction. Digestion rate of NFC were: 35.06, 14.86, 17.83 and 58.80, respectively for RB, WB, WSB and WCS. The choice of each protein and energy source will depend on market price and availability because there were

  17. Growing for different ends.

    Science.gov (United States)

    Catts, Oron; Zurr, Ionat

    2014-11-01

    Tissue engineering and regenerative biology are usually discussed in relation to biomedical research and applications. However, hand in hand with developments of this field in the biomedical context, other approaches and uses for non-medical ends have been explored. There is a growing interest in exploring spin off tissue engineering and regenerative biology technologies in areas such as consumer products, art and design. This paper outlines developments regarding in vitro meat and leather, actuators and bio-mechanic interfaces, speculative design and contemporary artistic practices. The authors draw on their extensive experience of using tissue engineering for non-medical ends to speculate about what lead to these applications and their possible future development and uses. Avoiding utopian and dystopian postures and using the notion of the contestable, this paper also mentions some philosophical and ethical consideration stemming from the use of non-medical approaches to tissue constructs. This article is part of a directed issue entitled: Regenerative Medicine: the challenge of translation. Copyright © 2014. Published by Elsevier Ltd.

  18. Seasonality, mobility, and livability.

    Science.gov (United States)

    2012-01-31

    Signature project 4a, Seasonality, Mobility, and Livability investigated the effects of weather, season, built environment, community amenities, attitudes, and demographics on mobility and quality of life (QOL). A four season panel survey exami...

  19. Extended season for northern butterflies.

    Science.gov (United States)

    Karlsson, Bengt

    2014-07-01

    Butterflies are like all insects in that they are temperature sensitive and a changing climate with higher temperatures might effect their phenology. Several studies have found support for earlier flight dates among the investigated species. A comparative study with data from a citizen science project, including 66 species of butterflies in Sweden, was undertaken, and the result confirms that most butterfly species now fly earlier during the season. This is especially evident for butterflies overwintering as adults or as pupae. However, the advancement in phenology is correlated with flight date, and some late season species show no advancement or have even postponed their flight dates and are now flying later in the season. The results also showed that latitude had a strong effect on the adult flight date, and most of the investigated species showed significantly later flights towards the north. Only some late flying species showed an opposite trend, flying earlier in the north. A majority of the investigated species in this study showed a general response to temperature and advanced their flight dates with warmer temperatures (on average they advanced their flight dates by 3.8 days/°C), although not all species showed this response. In essence, a climate with earlier springs and longer growing seasons seems not to change the appearance patterns in a one-way direction. We now see butterflies on the wings both earlier and later in the season and some consequences of these patterns are discussed. So far, studies have concentrated mostly on early season butterfly-plant interactions but also late season studies are needed for a better understanding of long-term population consequences.

  20. BIOTECHNOLOGY IN FRUIT GROWING

    Directory of Open Access Journals (Sweden)

    Z. Jurković

    2008-09-01

    Full Text Available Research studies in the area of biotechnologies in fruit growing started at the Agricultural Institute Osijek in 2006 with the establishment of the first experimental in vitro laboratory for micropropagation. The laboratory started an active research related to the Project "Biotechnological methods in fruit tree identification, selection and propagation" Project is part of program "Preservation and revitalization of grape and fruit autochthonous cultivars". The goal of this research is to determine genetic differences between autochthonous and introduced cultivars of cherry as well as cultivars and types of sour cherry, to find and optimize a method for fast recovery of clonal material. A great number of cherry cultivars and types within the population of cv. Oblacinska sour cherry exists in Croatia. A survey with the purpose of selecting autochthonous cultivars for further selection has been done in previous research. Differences have been found in a number of important agronomic traits within the populations of cv. Oblačinska sour cherry. Autochthonous cherry cultivars are suspected to be synonyms of known old cultivars which were introduced randomly and have been naturalized under a local name. Identification and description of cultivars and types of fruits is based on special visible properties which were measurable or notable. In this approach difficulties arise from the effect of non-genetic factors on expression of certain traits. Genetic-physiological problem of S allele autoincompatibility exists within cherry cultivars. Therefore it is necessary to put different cultivars in the plantation to pollinate each other. Apart form the fast and certain sort identification independent of environmental factors, biotechnological methods based on PCR enable faster virus detection compared with classical serologic methods and indexing and cover a wider range of plant pathogens including those undetectable by other methods. Thermotherapy and

  1. Growing Galaxies Gently

    Science.gov (United States)

    2010-10-01

    New observations from ESO's Very Large Telescope have, for the first time, provided direct evidence that young galaxies can grow by sucking in the cool gas around them and using it as fuel for the formation of many new stars. In the first few billion years after the Big Bang the mass of a typical galaxy increased dramatically and understanding why this happened is one of the hottest problems in modern astrophysics. The results appear in the 14 October issue of the journal Nature. The first galaxies formed well before the Universe was one billion years old and were much smaller than the giant systems - including the Milky Way - that we see today. So somehow the average galaxy size has increased as the Universe has evolved. Galaxies often collide and then merge to form larger systems and this process is certainly an important growth mechanism. However, an additional, gentler way has been proposed. A European team of astronomers has used ESO's Very Large Telescope to test this very different idea - that young galaxies can also grow by sucking in cool streams of the hydrogen and helium gas that filled the early Universe and forming new stars from this primitive material. Just as a commercial company can expand either by merging with other companies, or by hiring more staff, young galaxies could perhaps also grow in two different ways - by merging with other galaxies or by accreting material. The team leader, Giovanni Cresci (Osservatorio Astrofisico di Arcetri) says: "The new results from the VLT are the first direct evidence that the accretion of pristine gas really happened and was enough to fuel vigorous star formation and the growth of massive galaxies in the young Universe." The discovery will have a major impact on our understanding of the evolution of the Universe from the Big Bang to the present day. Theories of galaxy formation and evolution may have to be re-written. The group began by selecting three very distant galaxies to see if they could find evidence

  2. Variations and Trends in the Length of the Hydrologic Growing ...

    African Journals Online (AJOL)

    This paper examine the pattern of the Hydrologic Growing Season in a part of North western Nigeria in relation to crop Production and yield. It makes use of daily rainfall data obtained from Sokoto Agricultural Development project data were also obtained from the Nigeria Meteorological services Oshodi (SADP) in two ...

  3. Caracterização físico-química e aminas bioativas em vinhos da cv. Syrah I: efeito do ciclo de produção Physico-chemical characterization and bioactive amines in Syrah wines I: influence of growing season

    Directory of Open Access Journals (Sweden)

    Renata Vieira da Mota

    2009-06-01

    Full Text Available A ocorrência sistemática de dias chuvosos ou com alta nebulosidade e temperaturas ambientais elevadas prejudicam a maturação e a sanidade das uvas. Estudos recentes indicam que a alteração do ciclo de produção da videira através da poda possibilita colher uvas em épocas mais favoráveis à maturação, e com níveis de produção aceitáveis. Neste sentido, o presente trabalho teve como objetivo avaliar o perfil analítico dos vinhos de Syrah de safras de verão e inverno dos anos 2005 e 2006 produzidos em Três Corações (MG. Os vinhos do inverno de 2005 apresentaram valores superiores de pH (3,91 × 3,59, polifenóis totais (49,2 × 32,5, intensidade de cor (10,75 × 5,68, antocianinas (121,48 × 41,09 mg.L-1 , fenólicos totais (2,06 × 1,21 g.L-1, álcool (12,65 × 10,78% v/v e aminas bioativas (10,36 × 4,46 mg.L-1 quando comparados aos de verão. Comportamento semelhante foi obtido na safra de 2006. Os vinhos de inverno apresentaram maior conteúdo de compostos fenólicos, o que indica maior qualidade e maior potencial de guarda. Entretanto, o cultivo em estação seca e o elevado pH do mosto contribuíram para um aumento no teor de aminas bioativas, cuja evolução deve ser controlada na vinificação para evitar riscos à saúde humana.The systematic incidence of rainfall or overcast conditions and high temperatures impair grapes maturation and sanity. Recent studies show that vine growing season alteration through pruning enables berries harvest in climatic conditions more favorable to fruit maturation and that vines respond to pruning with acceptable yield levels. Under these conditions, the objective of the present work was to evaluate the physico-chemical characteristics of Syrah wine from winter and summer vintages of 2005 and 2006 cultivated in the city of Três Corações, State of Minas Gerais, Brazil. The winter wine from the 2005 vegetative cycle showed higher values of pH (3.91 × 3.59, total polyphenols (49.2 × 32

  4. Efeito de giberelina (GA3 e do bioestimulante 'Stimulate' na indução floral e produtividade do maracujazeiro-amarelo em condições de safra normal Effect of gibereline (GA3 and biostimulant 'Stimulate' in floral induction and yield of yellow passion fruit in conditions of normal growing season

    Directory of Open Access Journals (Sweden)

    Elma Machado Ataíde

    2006-12-01

    Full Text Available O objetivo do trabalho foi avaliar os efeitos de GA3, nas concentrações de 100; 200 e 300mg L-1 e do bioestimulante Stimulate®, em doses de 2,08; 4,17 e 6,25mL L-1, em duas aplicações via foliar, acrescidas de espalhante adesivo Silwett® a 0,05% e a exposição dos ramos à luminosidade, na indução floral e produtividade do maracujazeiro-amarelo, em condições de safra normal, em Araguari-MG. Aos 30 dias após a primeira aplicação dos tratamentos, iniciaram-se as avaliações do número de flores, com contagens diárias, nos dois lados da espaldeira, nos meses de setembro de 2002 a março de 2003. As colheitas dos frutos foram realizadas semanalmente, no período de novembro de 2002 a abril de 2003, observando-se a produção. O GA3 e o Stimulate não proporcionaram efeito significativo no número de flores, nas sete épocas, assim como no número total de flores. Não houve efeito dos tratamentos para a produtividade e produção total de frutos. Os ramos sob luminosidade pela tarde apresentaram maior número de flores, nos meses de setembro, dezembro, fevereiro e março. A interação entre os tratamentos e a exposição dos ramos à luminosidade não foi significativa para o número de flores, nas épocas avaliadas.The objective of this work was to evaluate the effects of GA3 , in concentrations of 100, 200 and 300mg L-1 and biostimulant StimulateTM, in doses of 2,08, 4,17 and 6,25 mL L-1, in two leaf applications, added with the adhesive spreader SilwettTM at 0,05% and branch exposure to brightness, on passion fruit in floral induction and yield, in conditions of normal growing season, in Araguari-MG. At 30 days after the first treatment application, the evaluation of flower number started, with daily counts, in both sides of the plants, from September 2002 to March 2003. Fruit harvest was realized weekly from November 2002 to April 2003, being observed the yield. GA3 and Stimulate did not provide significant effect on flower

  5. Life History Adaptations to Seasonality.

    Science.gov (United States)

    Varpe, Øystein

    2017-11-01

    Seasonality creates a template for many natural processes and evolutionary adaptations. Organisms are often faced with an annual cycle consisting of a productive (favorable) and unproductive period. This yearly cycle along with other seasonal variations in abiotic factors and associated biotic interactions form strong selection pressures shaping the scheduling of annual activities and the developmental stages and modes of life through the year. Annual decisions impact trade-offs that involve both current and future reproductive value (RV), and life history theory provides the foundation to understand these linkages between phenology and an organism's full life. Annual routine models further allow for multiple annual decisions to be optimized and predicted with respect to lifetime consequences. Studies of life history adaptations to seasonality are concerned with questions such as: within the productive season, should growth come first, followed by reproduction, or the other way around? What is the best time to diapause or migrate, and how will this timing impact other life history traits? Should energy reserves be built, to transfer resources from 1 year to the next, and allow for the spatial and temporal freedom of capital breeding? If offspring value is low during parts of the productive season, what is then the best alternative to reproduction: accumulate stores, grow, or wait in safety? To help answer these and other questions, I provide an overview of key theoretical concepts and some of the main life schedules, annual routines, and trade-offs involved. Adaptations to the unproductive period include diapause (dormancy), embryonic resting stages (eggs, seeds), energy reserves, and seasonal migrations. Adaptations to the productive window include rapid growth, high reproductive effort, capital breeding, and reproduction entrained to the annual cycle and with precise timing. Distinct annual routines, large body size, energy storage capacities, and parental care

  6. Ofertas de suplementos múltiplos para tourinhos Nelore na fase de recria em pastagens durante o período da seca: desempenho produtivo e características nutricionais Offers of multiple supplements to crossbreds Nellore young bulls in the growing stage on pasture, during the dry season: productive performance and nutritional characteristics

    Directory of Open Access Journals (Sweden)

    Marlos Oliveira Porto

    2011-11-01

    were evaluated. The area was divided in five paddocks of 2.0 ha, with availability of dry matter and potentially digestible dry matter of 3.88 and 2.22 t/ha, respectively. Thirty animals of 230.0 ± 6.14 kg initial weight and 8.5 ± 0.18 months of age were assigned in a completely randomized experimental design with five treatments, and four supplementation levels. Mineral mix (60 g/day and multiple supplements, formulated to supply different supplementation levels in the amounts of 0.5, 1.0, 1.5 and 2.0 kg/animal to supply 300 g/day of crude protein were evaluated. Animals responded to the use of multiples supplements, gaining more weight (88.72%, in addition to showing higher seric N-urea levels (19.95 vs. 9.66, when compared with animals fed diets supplied with mineral mix. Animals under supplementation showed higher intake of DM, OM, EE, NDF, NFC and TDN in relation to animals without supplementation, and this intake increased with the levels of supplement offer. Supplementation increased the coefficient of digestion of the majority of variables, regardless of the supplementation level. More moderate levels (0.5 kg of multiple supplement may be provided to young bulls in the growing stage, during the dry season, to stimulate intake of pasture; however the maximum microbial yield is achieved with 1.34 kg of supplement. The best responses of performance and nutritional characteristics can be obtained with dairy supply of supplement in levels of 0.5 to 1.34 kg/animal.

  7. Growing plants on atoll soils

    Energy Technology Data Exchange (ETDEWEB)

    Stone, E L; Migvar, L; Robison, W L

    2000-02-16

    year. Except on the driest of atolls, air temperature and humidity range only within limits set by the surrounding sea. There are no cold seasons, no frosts, no cold soils, no dry winds, and no periodic plagues of insects or diseases moving from miles away. Problems of soil drainage or salinity are few and easily recognized. Nor are there problems with acid soils, soil crusting, or erosion that challenge cultivators in many other areas. On the contrary, some of the black soils at the center of wide islands rank with the best soils of Russia and the American Midwest, except for their shortage of potassium and the uncertainties of rainfall. Some of these atoll soils contain more total nitrogen than many of the world's most productive agricultural soils and, in some, the total phosphorus content is so high as to be almost unbelievable--two to five tons of the element per acre. Certainly, problems exist in growing plants on atolls. There are also some special concerns not encountered in other environments, such as the wind and salt spray near shore. The two major physical limitations, however, are inadequate rainfall in some years and in many places, and soil fertility limitations. The alkaline or ''limy'' make-up of atoll soils means that a few plant nutrients, especially iron, limit growth of many introduced plants, and this is difficult to correct. As elsewhere in the world, many--but not all--atoll soils lack enough nitrogen and/or phosphorus for high yield, and all lack sufficient potassium. There is no practical way of overcoming drought except by use of tolerant plants such as coconut (ni) and Pandanus (bob), plus collection and careful use of whatever water is available. There are opportunities to overcome nutritional limitations mentioned above, first, by intensive use of all organic debris and household wastes in small gardens and, second, by use of commercial fertilizers. Imported fertilizers are expensive, certainly, but much less so on

  8. Algorithms for in-season nutrient management in cereals

    Science.gov (United States)

    The demand for improved decision making products for cereal production systems has placed added emphasis on using plant sensors in-season, and that incorporate real-time, site specific, growing environments. The objective of this work was to describe validated in-season sensor based algorithms prese...

  9. Rainy season characteristics of the Free State Province of South ...

    African Journals Online (AJOL)

    2011-01-20

    Jan 20, 2011 ... false onset of rains and the plants' crop water requirements are ... skill in forecasting of planting dates, but, when agrometeoro- .... Statistical analysis. The dates for the onset and cessation of rains, length of the growing season and seasonal rainfall were analysed for each station using Rainbow software, ...

  10. Late-season nitrogen applications in high-latitude strawberry ...

    African Journals Online (AJOL)

    USER

    2010-02-15

    Feb 15, 2010 ... The influence of late-season nitrogen (N) applications on the fruiting pattern of strawberry runner plants of 'Camarosa' was determined over three growing seasons. Experiments were carried out in high- latitude nurseries in northern California and fruit production trials were established in southern.

  11. Late-season nitrogen applications in high-latitude strawberry ...

    African Journals Online (AJOL)

    The influence of late-season nitrogen (N) applications on the fruiting pattern of strawberry runner plants of 'Camarosa' was determined over three growing seasons. Experiments were carried out in highlatitude nurseries in northern California and fruit production trials were established in southern California. A total of 80 ...

  12. Seasonal chemical composition of wall barley ( Hodreum murinum L ...

    African Journals Online (AJOL)

    Wall barley (Hodreum murinum L.) is an annual cool-season grass species that grows in areas with a Mediterranean climate. It has potential as a forage source in Jordan. The objective was to determine seasonal chemical composition of wall barley grown under sub-humid Mediterranean conditions. A field trial

  13. EFFECTS OF SEASON OF SOWING ON WATER USE AND YIELD ...

    African Journals Online (AJOL)

    2000-05-09

    May 9, 2000 ... ... season sowing, the relative water use (ETa/Eo) values (the ratio of actual evapotranspiration, ETa to open water evaporation, Eo) varied from 1.14 at the beginning of the growing season to 0.04 at crop maturity. The values of ETa/Eo and evapotranspiration deficit (ETd) indicated that during the crop cycle, ...

  14. Seasonal thermal energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Allen, R.D.; Kannberg, L.D.; Raymond, J.R.

    1984-05-01

    This report describes the following: (1) the US Department of Energy Seasonal Thermal Energy Storage Program, (2) aquifer thermal energy storage technology, (3) alternative STES technology, (4) foreign studies in seasonal thermal energy storage, and (5) economic assessment.

  15. Influenza Seasonal Summary, 2014-2015 Season

    Science.gov (United States)

    2015-08-14

    upcoming season. Influenza vaccines are available as a high-dose vaccine , inu·adennal vaccine , regulru· flu shot, or nasal spray flu vaccine , which is...seasonlflu-season.htm. Updated October 22, 2014. Accessed June 19, 2015. 6. Key facts about seasonal flu vaccine . Centers for Disease Conu·ol and...Accessed June 19, 2015. 8. Use of antivirals. Centers for Disease Conu·ol and Prevention Web site. http:/ /cdc. gov/ flu / professionals /antivirals/antiviral

  16. Seasonal Variation in Epidemiology

    Science.gov (United States)

    Marrero, Osvaldo

    2013-01-01

    Seasonality analyses are important in medical research. If the incidence of a disease shows a seasonal pattern, then an environmental factor must be considered in its etiology. We discuss a method for the simultaneous analysis of seasonal variation in multiple groups. The nuts and bolts are explained using simple trigonometry, an elementary…

  17. Growing Concerns With Workplace Incivility.

    Science.gov (United States)

    Collins, Natasha Renee; Rogers, Bonnie

    2017-11-01

    Workplace incivility (WPI) is a growing issue across all public and private sectors. Occupational and environmental health nurses can educate employees and management about WPI, its risk factors and characteristics, and ways to reduce incidents of WPI.

  18. Exposure to vibrations in wine growing

    Directory of Open Access Journals (Sweden)

    Domenico Pessina

    2013-09-01

    Full Text Available Apart the winter period, the activity in specialized agricultural cultivations (i.e. wine- and fruit-growing is distributed for a long period of the year. Some tasks, such as pesticide distribution, are repeated several times during the growing season. On the other hand, mechanization is one of the pillars on which is based the modern agriculture management. As a consequence, in wine growing the tractor driver has to be considered a worker potentially subjected to high level of vibrations, due to the poor machinery conditions often encountered, and sometimes to the rough soil surface of the vineyard combined with the high travelling speed adopted in carrying out many operations. About vibrations, the Italian Decree 81/08 basically refers to the European Directive 2002/44/CE, that provides some very strict limits of exposure, both for whole body and hand-arm districts. In Oltrepo pavese, a large hilly area located the south part of the Pavia province (Lombardy - Italy wine growing is the main agricultural activity; for this reason, a detailed survey on the vibration levels recorded at the tractor driver’s seat was carried out, in order to ascertain the real risk to which the operators are exposed. The activity in wine growing has been classified into 6 groups of similar tasks, as follows: 1. canopy management: pruning, trimming, binding, stripping, etc.; 2. soil management: harrowing, hoeing, subsoiling etc.; 3. inter-row management: chopping of pruning , pinching, grass mowing, etc.; 4. crop protection: pesticides and fungicides distribution, sulfidation, foliar fertilization, etc.; 5. grape harvesting: manual or mechanical; 6. transport: from the vineyard to the cellar. For each group of tasks, the vibration levels on 3 the traditional axes (x, y and z were recorded, and then an exposure time was calculated for each of them, in order to ascertain the risk level in comparison to what provided by the dedicated standard. Finally, a detailed

  19. Cool Season Paleotemperatures at Tree Line in Taiwan

    Science.gov (United States)

    Wright, W. E.; Chan, M.

    2011-12-01

    Taiwan has over 200 mountains whose peaks exceed 3,000 meters in elevation. Despite straddling the Tropic of Cancer, the higher peaks have snow and freezing temperatures every winter. Trees growing above 3,500 meters show clear temperature variation, even producing frost rings. Yet unlike temperate tree-line species, with their warm season temperature signal, trees growing at Taiwan's tree line show sensitivity to cool season temperatures. Juniperus squamata growing above 3,500 meters in central Taiwan have ring width time series that commonly exceed 600 years. Presented are the first dendroclimatological analyses from Taiwanese Juniperus squamata.

  20. Effect of land cover and use on dry season river runoff, runoff efficiency, and peak storm runoff in the seasonal tropics of Central Panama

    Science.gov (United States)

    Ogden, Fred L.; Crouch, Trey D.; Stallard, Robert F.; Hall, Jefferson S.

    2013-01-01

    A paired catchment methodology was used with more than 3 years of data to test whether forests increase base flow in the dry season, despite reduced annual runoff caused by evapotranspiration (the “sponge-effect hypothesis”), and whether forests reduce maximum runoff rates and totals during storms. The three study catchments were: a 142.3 ha old secondary forest, a 175.6 ha mosaic of mixed age forest, pasture, and subsistence agriculture, and a 35.9 ha actively grazed pasture subcatchment of the mosaic catchment. The two larger catchments are adjacent, with similar morphology, soils, underlying geology, and rainfall. Annual water balances, peak runoff rates, runoff efficiencies, and dry season recessions show significant differences. Dry season runoff from the forested catchment receded more slowly than from the mosaic and pasture catchments. The runoff rate from the forest catchment was 1–50% greater than that from the similarly sized mosaic catchment at the end of the dry season. This observation supports the sponge-effect hypothesis. The pasture and mosaic catchment median runoff efficiencies were 2.7 and 1.8 times that of the forest catchment, respectively, and increased with total storm rainfall. Peak runoff rates from the pasture and mosaic catchments were 1.7 and 1.4 times those of the forest catchment, respectively. The forest catchment produced 35% less total runoff and smaller peak runoff rates during the flood of record in the Panama Canal Watershed. Flood peak reduction and increased streamflows through dry periods are important benefits relevant to watershed management, payment for ecosystem services, water-quality management, reservoir sedimentation, and fresh water security in the Panama Canal watershed and similar tropical landscapes.

  1. Historical warnings of future food insecurity with unprecedented seasonal heat.

    Science.gov (United States)

    Battisti, David S; Naylor, Rosamond L

    2009-01-09

    Higher growing season temperatures can have dramatic impacts on agricultural productivity, farm incomes, and food security. We used observational data and output from 23 global climate models to show a high probability (>90%) that growing season temperatures in the tropics and subtropics by the end of the 21st century will exceed the most extreme seasonal temperatures recorded from 1900 to 2006. In temperate regions, the hottest seasons on record will represent the future norm in many locations. We used historical examples to illustrate the magnitude of damage to food systems caused by extreme seasonal heat and show that these short-run events could become long-term trends without sufficient investments in adaptation.

  2. Seasonality of tuberculosis

    Directory of Open Access Journals (Sweden)

    Auda Fares

    2011-01-01

    Full Text Available Objectives: This study was designed to review previous studies and analyse the current knowledge and controversies related to seasonal variability of tuberculosis (TB to examine whether TB has an annual seasonal pattern. Study Design and Methods: Systematic review of peer reviewed studies identified through literature searches using online databases belonging to PubMed and the Cochrane library with key words "Tuberculosis, Seasonal influence" and " Tuberculosis, Seasonal variation". The search was restricted to articles published in English. The references of the identified papers for further relevant publications were also reviewed. Results: Twelve studies conducted between the period 1971 and 2006 from 11 countries/regions around the world (South Western Cameroon, South Africa, India, Hong Kong, Japan, Kuwait, Spain, UK, Ireland, Russia, and Mongolia were reviewed. A seasonal pattern of tuberculosis with a mostly predominant peak is seen during the spring and summer seasons in all of the countries (except South Western Cameroon and Russia. Conclusions: The observation of seasonality leads to assume that the risk of transmission of M. tuberculosis does appear to be the greatest during winter months. Vitamin D level variability, indoor activities, seasonal change in immune function, and delays in the diagnosis and treatment of tuberculosis are potential stimuli of seasonal tuberculosis disease. Additionally, seasonal variation in food availability and food intake, age, and sex are important factors which can play a role in the tuberculosis notification variability. Prospective studies regarding this topic and other related subjects are highly recommended.

  3. Growing Oppression, Growing Resistance : LGBT Activism and Europeanisation in Macedonia

    NARCIS (Netherlands)

    Miškovska Kajevska, A.; Bilić, B.

    2016-01-01

    This chapter provides one of the first socio-historical overviews of the LGBT groups in Macedonia and argues that an important impetus for the proliferation of LGBT activities has been the growing state-endorsed homophobia starting from 2008. The homophobic rhetoric of the ruling parties was clearly

  4. Responses of inulin content and inulin yield of Jerusalem artichoke genotypes to seasonal environments

    Science.gov (United States)

    Seasonal variation (e.g. temperature and photoperiod) between growing seasons might affect inulin content and inulin yield of Jerusalem artichoke. However, there is limited information on genotypic response to seasons for inulin content and inulin yield. The objective of this study was to investig...

  5. Disappearing seasonality in birthweight.

    Science.gov (United States)

    Sohn, Kitae

    2016-11-01

    We estimated seasonality in birthweight over time and assessed how seasonality changed. We analyzed all full-term singletons (N = 8,268,693) born in South Korea in 1997-2014. We first pooled all years and regressed birthweight on birth season while flexibly controlling for a large set of covariates. We then repeated the analysis by birth year and charted the trends in seasonality in birthweight. When we pooled all years, babies born in winter were the heaviest, while those born in summer the lightest; the difference in birthweight was about 11 g. When we analyzed the data by birth year, however, seasonality almost disappeared by the end of the period. Whatever causes the seasonality has lost its influence in Korea. Replication studies can determine whether other countries exhibit the same patterns. Am. J. Hum. Biol. 28:767-773, 2016. © 2016Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  6. Timing of Seasonal Sales.

    OpenAIRE

    Courty, Pascal; Hao, Li

    1999-01-01

    We present a model of timing of seasonal sales where stores choose several designs at the beginning of the season without knowing wich one, if any, will be fashionable. Fashionable designs have a chance to fetch high prices in fashion markets while non-fashionable ones must be sold in a discount market. In the beginning of the season, stores charge high prices in the hope of capturing their fashion market. As the end of the season approaches with goods still on the shelves, stores adjust down...

  7. Exploring Classroom Hydroponics. Growing Ideas.

    Science.gov (United States)

    National Gardening Association, Burlington, VT.

    Growing Ideas, the National Gardening Association's series for elementary, middle, and junior high school educators, helps teachers engage students in using plants and gardens as contexts for developing a deeper, richer understanding of the world around them. This volume's focus is on hydroponics. It presents basic hydroponics information along…

  8. Growing Patterns: Seeing beyond Counting

    Science.gov (United States)

    Markworth, Kimberly A.

    2012-01-01

    Over the past two decades, mathematical patterns have been acknowledged as important early components of children's development of algebraic reasoning (NCTM 2000). In particular, growing patterns have attracted significant attention as a context that helps students develop an understanding of functional relationships (Lee and Freiman 2006; Moss et…

  9. Organization of growing random networks

    Energy Technology Data Exchange (ETDEWEB)

    Krapivsky, P. L.; Redner, S.

    2001-06-01

    The organizational development of growing random networks is investigated. These growing networks are built by adding nodes successively, and linking each to an earlier node of degree k with an attachment probability A{sub k}. When A{sub k} grows more slowly than linearly with k, the number of nodes with k links, N{sub k}(t), decays faster than a power law in k, while for A{sub k} growing faster than linearly in k, a single node emerges which connects to nearly all other nodes. When A{sub k} is asymptotically linear, N{sub k}(t){similar_to}tk{sup {minus}{nu}}, with {nu} dependent on details of the attachment probability, but in the range 2{lt}{nu}{lt}{infinity}. The combined age and degree distribution of nodes shows that old nodes typically have a large degree. There is also a significant correlation in the degrees of neighboring nodes, so that nodes of similar degree are more likely to be connected. The size distributions of the in and out components of the network with respect to a given node{emdash}namely, its {open_quotes}descendants{close_quotes} and {open_quotes}ancestors{close_quotes}{emdash}are also determined. The in component exhibits a robust s{sup {minus}2} power-law tail, where s is the component size. The out component has a typical size of order lnt, and it provides basic insights into the genealogy of the network.

  10. Quantification of the effect of terrace maintenance on soil erosion: two seasons of monitoring experiments in Cyprus

    Science.gov (United States)

    Camera, Corrado; Djuma, Hakan; Zoumides, Christos; Eliades, Marinos; Charalambous, Katerina; Bruggeman, Adriana

    2017-04-01

    , which corresponds to a soil loss reduction of 98%. From the closed plots, we derived an erosion rate of 2.8 t ha-1 y-1 for degraded terraces and 0.05 t ha-1 y-1 for well-maintained terraces. Also, soil moisture monitoring confirmed that standing terraces favor surface water infiltration. For the second season (winter 2016/17), given the differences in results between open and closed traps and therefore the difficulty in consistently upscaling the results, we modified the monitoring design. The 11 traps were kept, all open, but the comparison between maintained and degraded areas is carried out on a sub-catchment basis, rather than on a section basis. We restored the whole sub-catchment of terrace A (≈480-m2) to be considered the maintained treatment of our experiment and kept the sub-catchment of terrace B (≈600-m2) in degraded conditions. To obtain the sub-catchment erosion rate, the sediment collected in the traps is averaged on running meter of wall and integrated on the wall length. This research is supported by the European Union's FP7 RECARE Project (GA 603498).

  11. Establishing native warm season grasses on Eastern Kentucky strip mines

    Energy Technology Data Exchange (ETDEWEB)

    Barnes, T.G.; Larkin, J.L.; Arnett, M.B. [Univ. of Kentucky, Lexington, KY (United States). Dept. of Forestry

    1998-12-31

    The authors evaluated various methods of establishing native warm season grasses on two reclaimed Eastern Kentucky mines from 1994--1997. Most current reclamation practices incorporate the use of tall fescue (Festuca arundinacea) and other cool-season grasses/legumes that provide little wildlife habitats. The use of native warm season grasses will likely improve wildlife habitat on reclaimed strip mines. Objectives of this study were to compare the feasibility of establishing these grasses during fall, winter, or spring using a native rangeland seeder or hydroseeding; a fertilizer application at planting; or cold-moist stratification prior to hydroseeding. Vegetative cover, bare ground, species richness, and biomass samples were collected at the end of each growing season. Native warm season grass plantings had higher plant species richness compared to cool-season reclamation mixtures. There was no difference in establishment of native warm season grasses as a result of fertilization or seeding technique. Winter native warm season grass plantings were failures and cold-moist stratification did not increase plant establishment during any season. As a result of a drought during 1997, both cool-season and warm season plantings were failures. Cool-season reclamation mixtures had significantly more vegetative cover and biomass compared to native warm season grass mixtures and the native warm season grass plantings did not meet vegetative cover requirements for bond release. Forbs and legumes that established well included pale purple coneflower (Echinacea pallida), lance-leaf coreopsis (Coreopsis lanceolata), round-headed lespedeza (Lespedeza capitata), partridge pea (Cassia fasiculata), black-eyed susan (Rudbeckia hirta), butterfly milkweed (Asclepias tuberosa), and bergamot (Monarda fistulosa). Results from two demonstration plots next to research plots indicate it is possible to establish native warm season grasses on Eastern Kentucky strip mines for wildlife habitat.

  12. Seasonal community succession of the phyllosphere microbiome.

    Science.gov (United States)

    Copeland, Julia K; Yuan, Lijie; Layeghifard, Mehdi; Wang, Pauline W; Guttman, David S

    2015-03-01

    The leaf microbiome is influenced by both biotic and abiotic factors. Currently, we know little about the relative importance of these factors in determining microbiota composition and dynamics. To explore this issue, we collected weekly leaf samples over a 98-day growing season from multiple cultivars of common bean, soybean, and canola planted at three locations in Ontario, Canada, and performed Illumina-based microbiome analysis. We find that the leaf microbiota at the beginning of the season is very strongly influenced by the soil microbiota but, as the season progresses, it differentiates, becomes significantly less diverse, and transitions to having a greater proportion of leaf-specific taxa that are shared among all samples. A phylogenetic investigation of communities by reconstruction of unobserved states imputation of microbiome function inferred from the taxonomic data found significant differences between the soil and leaf microbiome, with a significant enrichment of motility gene categories in the former and metabolic gene categories in the latter. A network co-occurrence analysis identified two highly connected clusters as well as subclusters of putative pathogens and growth-promoting bacteria. These data reveal some of the complex ecological dynamics that occur in microbial communities over the course of a growing season and highlight the importance of community succession.

  13. Growing random networks with fitness

    OpenAIRE

    Ergun, G.; Rodgers, GJ

    2001-01-01

    Three models of growing random networks with fitness dependent growth rates are analysed using the rate equations for the distribution of their connectivities. In the first model (A), a network is built by connecting incoming nodes to nodes of connectivity $k$ and random additive fitness $\\eta$, with rate $(k-1)+ \\eta $. For $\\eta >0$ we find the connectivity distribution is power law with exponent $\\gamma=+2$. In the second model (B), the network is built by connecting nodes to nodes of conn...

  14. Neural-like growing networks

    Science.gov (United States)

    Yashchenko, Vitaliy A.

    2000-03-01

    On the basis of the analysis of scientific ideas reflecting the law in the structure and functioning the biological structures of a brain, and analysis and synthesis of knowledge, developed by various directions in Computer Science, also there were developed the bases of the theory of a new class neural-like growing networks, not having the analogue in world practice. In a base of neural-like growing networks the synthesis of knowledge developed by classical theories - semantic and neural of networks is. The first of them enable to form sense, as objects and connections between them in accordance with construction of the network. With thus each sense gets a separate a component of a network as top, connected to other tops. In common it quite corresponds to structure reflected in a brain, where each obvious concept is presented by certain structure and has designating symbol. Secondly, this network gets increased semantic clearness at the expense owing to formation not only connections between neural by elements, but also themselves of elements as such, i.e. here has a place not simply construction of a network by accommodation sense structures in environment neural of elements, and purely creation of most this environment, as of an equivalent of environment of memory. Thus neural-like growing networks are represented by the convenient apparatus for modeling of mechanisms of teleological thinking, as a fulfillment of certain psychophysiological of functions.

  15. Seasonality of cavitation and frost fatigue in Acer mono Maxim.

    Science.gov (United States)

    Zhang, Wen; Feng, Feng; Tyree, Melvin T

    2017-12-08

    Although cavitation is common in plants, it is unknown whether the cavitation resistance of xylem is seasonally constant or variable. We tested the changes in cavitation resistance of Acer mono before and after a controlled cavitation-refilling and freeze-thaw cycles for a whole year. Cavitation resistance was determined from 'vulnerability curves' showing the percent loss of conductivity (PLC) versus xylem tension. Cavitation fatigue was defined as a reduction of cavitation resistance following a cavitation-refilling cycle while frost fatigue was caused by a freeze-thaw cycle. A. mono developed seasonal changes in native embolisms; values were relatively high during winter but relatively low and constant throughout the growing season. Cavitation fatigue occurred and changed seasonally during the 12-month cycle; the greatest fatigue response occurred during summer and the weakest during winter, and the transitions occurred during spring and autumn. A. mono was highly resistant to frost damage during the relatively mild winter months; however, a quite different situation occurred during the growing season, as the seasonal trend of frost fatigue was strikingly similar to that of cavitation fatigue. Seasonality changes in cavitation resistance may be caused by seasonal changes in the mechanical properties of the pit membranes. This article is protected by copyright. All rights reserved.

  16. Measuring efficiency of rice growing farmers using data envelopment analysis

    Science.gov (United States)

    Zaibidi, Nerda Zura; Kasim, Maznah Mat; Ramli, Razamin; Baten, Md. Azizul; Khan, Sahubar Ali Nadhar

    2015-12-01

    Self-sufficiency in rice production has been the main issue in Malaysia agriculture. It is significantly low and does not comply with the current average rice yield of 3.7 tons per ha per season. One of the best options and the most effective way to improve rice productivity is through more efficient utilization of paddy farmers. Getting farmers to grow rice is indeed a challenge when they could very well be making better money doing something else. This paper attempts to study the efficiency of rice growing farmers in Kubang Pasu using Data Envelopment Analysis model. For comparative analysis, three scenarios are considered in this study in measuring efficiency of rice growing farmers. The first scenario considers only fertilizer factor as an input while for the second, the land size is added as another factor. The third scenario considers more details about the inputs such as the type of fertilizer, NPK and mixed and also land tenureship and size. In all scenarios, the outputs are rice yield (tons) and the profit (RM). As expected, the findings show that the third scenario establishes the highest number of efficient rice growing farmers. It reveals that the combination of outputs and inputs chosen has significant contribution in measuring efficiency of rice growing farmers.

  17. Estimating seasonal evapotranspiration from temporal satellite images

    Science.gov (United States)

    Singh, Ramesh K.; Liu, Shu-Guang; Tieszen, Larry L.; Suyker, Andrew E.; Verma, Shashi B.

    2012-01-01

    Estimating seasonal evapotranspiration (ET) has many applications in water resources planning and management, including hydrological and ecological modeling. Availability of satellite remote sensing images is limited due to repeat cycle of satellite or cloud cover. This study was conducted to determine the suitability of different methods namely cubic spline, fixed, and linear for estimating seasonal ET from temporal remotely sensed images. Mapping Evapotranspiration at high Resolution with Internalized Calibration (METRIC) model in conjunction with the wet METRIC (wMETRIC), a modified version of the METRIC model, was used to estimate ET on the days of satellite overpass using eight Landsat images during the 2001 crop growing season in Midwest USA. The model-estimated daily ET was in good agreement (R2 = 0.91) with the eddy covariance tower-measured daily ET. The standard error of daily ET was 0.6 mm (20%) at three validation sites in Nebraska, USA. There was no statistically significant difference (P > 0.05) among the cubic spline, fixed, and linear methods for computing seasonal (July–December) ET from temporal ET estimates. Overall, the cubic spline resulted in the lowest standard error of 6 mm (1.67%) for seasonal ET. However, further testing of this method for multiple years is necessary to determine its suitability.

  18. Seasonal differences in leaf-level physiology give lianas a competitive advantage over trees in a tropical seasonal forest.

    Science.gov (United States)

    Cai, Zhi-Quan; Schnitzer, Stefan A; Bongers, Frans

    2009-08-01

    Lianas are an important component of most tropical forests, where they vary in abundance from high in seasonal forests to low in seasonal forests. We tested the hypothesis that the physiological ability of lianas to fix carbon (and thus grow) during seasonal drought may confer a distinct advantage in seasonal tropical forests, which may explain pan-tropical liana distributions. We compared a range of leaf-level physiological attributes of 18 co-occurring liana and 16 tree species during the wet and dry seasons in a tropical seasonal forest in Xishuangbanna, China. We found that, during the wet season, lianas had significantly higher CO(2) assimilation per unit mass (A(mass)), nitrogen concentration (N(mass)), and delta(13)C values, and lower leaf mass per unit area (LMA) than trees, indicating that lianas have higher assimilation rates per unit leaf mass and higher integrated water-use efficiency (WUE), but lower leaf structural investments. Seasonal variation in CO(2) assimilation per unit area (A(area)), phosphorus concentration per unit mass (P(mass)), and photosynthetic N-use efficiency (PNUE), however, was significantly lower in lianas than in trees. For instance, mean tree A(area) decreased by 30.1% from wet to dry season, compared with only 12.8% for lianas. In contrast, from the wet to dry season mean liana delta(13)C increased four times more than tree delta(13)C, with no reduction in PNUE, whereas trees had a significant reduction in PNUE. Lianas had higher A(mass) than trees throughout the year, regardless of season. Collectively, our findings indicate that lianas fix more carbon and use water and nitrogen more efficiently than trees, particularly during seasonal drought, which may confer a competitive advantage to lianas during the dry season, and thus may explain their high relative abundance in seasonal tropical forests.

  19. Seasonality of Suicidal Behavior

    Directory of Open Access Journals (Sweden)

    Teodor T. Postolache

    2012-02-01

    Full Text Available A seasonal suicide peak in spring is highly replicated, but its specific cause is unknown. We reviewed the literature on suicide risk factors which can be associated with seasonal variation of suicide rates, assessing published articles from 1979 to 2011. Such risk factors include environmental determinants, including physical, chemical, and biological factors. We also summarized the influence of potential demographic and clinical characteristics such as age, gender, month of birth, socioeconomic status, methods of prior suicide attempt, and comorbid psychiatric and medical diseases. Comprehensive evaluation of risk factors which could be linked to the seasonal variation in suicide is important, not only to identify the major driving force for the seasonality of suicide, but also could lead to better suicide prevention in general.

  20. 2012 Swimming Season Factsheets

    Science.gov (United States)

    To help beachgoers make informed decisions about swimming at U.S. beaches, EPA annually publishes state-by-state data about beach closings and advisories for the previous year's swimming season. These fact sheets summarize that information by state.

  1. Seasonal groundwater turnover

    OpenAIRE

    Nordell, Bo; Engström, Maria

    2006-01-01

      Seasonal air temperature variations and corresponding changes in groundwater temperature cause convective movements in groundwater similar to the seasonal turnover in lakes. Numerical simulations were performed to investigate the natural conditions for thermally driven groundwater convection to take place. Thermally driven convection could be triggered by a horizontal groundwater flow, Convection then starts at a considerably lower Rayleigh number (Ra) than the general critical Rayleigh ...

  2. Fontes de energia em suplementos múltiplos para recria de novilhos mestiços em pastejo durante o período de transição seca/águas: desempenho produtivo e características nutricionais Energy sources in multiple supplements for growing crossbred steers on pastureduring the dry to rainy seasons: performance and nutritional characteristics

    Directory of Open Access Journals (Sweden)

    Michele Lopes do Nascimento

    2009-06-01

    starch or fiber in multiples supplements on performance and nutritional characteristics of finishing crossbred steers in the dry/rainy transition season, grazing Brachiaria decumbens Stapf. The experimental area was divided into 5 paddocks with 2.0 ha each, with dry matter availability of 4.309,4 kg/ha. Twenty-four castrated crossbred steers were used, initially 24 month old and 314.46 kg. For each animal, one of the five treatments was randomly applied: mineral mixture ad libitum, pearl millet grain or corn grain, as starchy energy sources, citrus pulp or wheat bran, as fibrous energy sources. To the different energy sources, the following were added: mineral mixture, cotton seed meal and urea, so that they composed supplements with 30% of crude protein based on the natural matter, supplied at the level of 1.5 kg/animal/day. In relation to control group, significant effect of the supplementation on the diary gain was not verified. The average daily gain obtained with the fibrous sources was 17.43% higher than that obtained with the starchy sources. The dry matter (DM, organic matter, non-fibrous carbohydrates (NFC, crude protein (CP, ether extract, digestible DM, total digestible nutrients and neutral detergent fiber (NDF indigestible intakes (kg/animal/day was higher for supplemented animals in relation to the control group. CP and NFC total apparent digestibility were lower for animals that received only MM. Excretion of urea by urine, and the urea plasmatic level were lower for animals fed MM only. Multiple supplements with high digestible fiber sources in association with urea promoted better performance to the animals than that formulated with starchy sources and urea. The supplementation in the dry/rainy season, in 0.4% of the BW do not affect the NDF digestibility, regardless of the energy source.

  3. Fontes de energia em suplementos múltiplos de auto-regulação de consumo na recria de novilhos mestiços em pastagens de Brachiaria decumbens durante o período das águas Energy sources in multiple supplements of self-feed of growing crossbred steers at pastures of Brachiaria Decumbens in wet season

    Directory of Open Access Journals (Sweden)

    Mário Fonseca Paulino

    2005-06-01

    Full Text Available Objetivou-se avaliar o efeito de diferentes fontes energéticas em suplementos múltiplos de auto-regulação de consumo sobre o ganho médio diário (GMD, ganho de peso total (GPT, pH e a concentração de amônia ruminal em novilhos recriados em pastejo no período das águas. Foram avaliados suplementos contendo grão de milho moído (GMM, milho desintegrado com palha e sabugo (MDPS, sorgo moído (SM e tratamento controle (mistura mineral - MM. Utilizaram-se 16 novilhos mestiços Holandês-Zebu, não-castrados, com 12 meses de idade e peso médio inicial de 265 kg para avaliar o desempenho. Os parâmetros ruminais foram obtidos utilizando-se quatro novilhos mestiços Holandês-Zebu fistulados no rúmen. O pH do líquido ruminal variou de 6,43 a 6,62 (média de 6,55, não sendo influenciado pelas quantidades de sal e de suplemento consumidas. As concentrações de amônia foram de 9,61; 25,71; 24,45 e 26,04 mg/dL, respectivamente para os tratamentos MM, GMM, MDPS, SM. Não se verificou diferença entre os tratamentos, contudo o suplemento MDPS proporcionou ganhos adicionais em torno de 220 g/animal/dia. Maiores concentrações de amônia ruminal foram observadas nos animais suplementados.The effect of different energy sources in multiple supplements of self-feed on the average daily gain (ADG, total weight gain (TWG, pH and ruminal ammonia concentration of steers grazed at pasture in the wet season was evaluated. Treatments were supplements containing ground corn grain (GCG, corn, ears and cob (CEC, ground sorghum (GS and control treatment (mineral mix - MM. Sixteen crossbreed steers with initial age and weight of 12 months old and 265 kg were used. Ruminal parameters were obtained from four crossbreed steers fistulated in the rumen. The pH values ranged from 6.43 to 6.62, with an average of 6.55 not having effect for the amounts of salt and supplement consumed. Concentrations were 9.61, 25.71, 24.45 and 26.04 mg/dL, respectively, for MM, GCG

  4. Mechanisms contributing to seasonal homeostasis of minimum leaf water potential and predawn disequilibrium between soil and plant water potential in Neotropical savanna trees.

    Science.gov (United States)

    Sandra J. Bucci; Guillermo Goldstein; Frederick C. Meinzer; Augusto C. Franco; Paula Campanello; Fabián G. Scholz

    2005-01-01

    Seasonal regulation of leaf water potential (ΨL) was studied in eight dominant woody savanna species growing in Brazilian savanna (Cerrado) sites that experience a 5-month dry season. Despite marked seasonal variation in precipitation and air saturation deficit (D), seasonal differences in midday minimum Ψ...

  5. Growing the Blockchain information infrastructure

    DEFF Research Database (Denmark)

    Jabbar, Karim; Bjørn, Pernille

    2017-01-01

    In this paper, we present ethnographic data that unpacks the everyday work of some of the many infrastructuring agents who contribute to creating, sustaining and growing the Blockchain information infrastructure. We argue that this infrastructuring work takes the form of entrepreneurial actions......, which are self-initiated and primarily directed at sustaining or increasing the initiator’s stake in the emerging information infrastructure. These entrepreneurial actions wrestle against the affordances of the installed base of the Blockchain infrastructure, and take the shape of engaging...... or circumventing activities. These activities purposefully aim at either influencing or working around the enablers and constraints afforded by the Blockchain information infrastructure, as its installed base is gaining inertia. This study contributes to our understanding of the purpose of infrastructuring, seen...

  6. Growing Vertical in the Flatland.

    Science.gov (United States)

    Robinson, Joshua A

    2016-01-26

    The world of two-dimensional (2D) heterostructures continues to expand at a rate much greater than anyone could have predicted 10 years ago, but if we are to make the leap from science to technology, many materials challenges must still be overcome. Recent advances, such as those by Liu et al. in this issue of ACS Nano, demonstrate that it is possible to grow rotationally commensurate 2D heterostructures, which could pave the way toward single crystal van der Waals solids. In this Perspective, I provide some insight into a few of the challenges associated with growth of heterostructures, and discuss some of the recent works that help us better understand synthetic realization of 2D heterostructures.

  7. Viking Disruptions or Growing Integration?

    DEFF Research Database (Denmark)

    Sindbæk, Søren Michael

    2012-01-01

    Long-distance communication has emerged as a particular focus for archaeological exploration using network theory, analysis, and modelling. Initial attempts to adapt methods from social network analysis to archaeological data have, however, struggled to produce decisive results. This paper...... demonstrates how formal network analysis can be combined with a contextual reading of evidence relating to a long-distance communication network in the past. A study of the combined distributions of ten vessel types in 152 settlement sites from the 10th century suggests the outline of the core structure...... of the network. The model implies that 10th century long-distance exchange in the North Sea region featured long-distance links equal to those of the Carolingian emporia trade, and represented a growth in terms of new axes of integration, above all the growing links between the Scandinavian Peninsula...

  8. Growing bubbles rising in line

    Directory of Open Access Journals (Sweden)

    John F. Harper

    2001-01-01

    Full Text Available Over many years the author and others have given theories for bubbles rising in line in a liquid. Theory has usually suggested that the bubbles will tend towards a stable distance apart, but experiments have often showed them pairing off and sometimes coalescing. However, existing theory seems not to deal adequately with the case of bubbles growing as they rise, which they do if the liquid is boiling, or is a supersaturated solution of a gas, or simply because the pressure decreases with height. That omission is now addressed, for spherical bubbles rising at high Reynolds numbers. As the flow is then nearly irrotational, Lagrange's equations can be used with Rayleigh's dissipation function. The theory also works for bubbles shrinking as they rise because they dissolve.

  9. Morphogenesis of Growing Soft Tissues

    Science.gov (United States)

    Dervaux, Julien; Ben Amar, Martine

    2008-08-01

    Recently, much attention has been given to a noteworthy property of some soft tissues: their ability to grow. Many attempts have been made to model this behavior in biology, chemistry, and physics. Using the theory of finite elasticity, Rodriguez has postulated a multiplicative decomposition of the geometric deformation gradient into a growth-induced part and an elastic one needed to ensure compatibility of the body. In order to fully explore the consequences of this hypothesis, the equations describing thin elastic objects under finite growth are derived. Under appropriate scaling assumptions for the growth rates, the proposed model is of the Föppl von Kármán type. As an illustration, the circumferential growth of a free hyperelastic disk is studied.

  10. Frequência de suplementação e fontes de proteína para recria de bovinos em pastejo no período seco: desempenho produtivo e econômico Supplementation frequency and proteins sources for growing of steers in pasture during the dry season: productive and economical performance

    Directory of Open Access Journals (Sweden)

    Nelcino Francisco de Paula

    2010-04-01

    effects of the frequency of supplementation with two proteins sources on productive and economical performance (experiment 1 and the nutrients digestibility of steers in supplemented pasture during the dry season over a year. It was used twenty weaned zebu calves at the age of 10 months and initial live weight (LW of 208.43 kg, distributed in four paddocks of Brachiaria brizantha cv. Marandu, each one with 1.6 ha. Both experiments were structured in 2 × 2 factorial arrangement with two supplements (with soybean meal and high energy cottonseed meal. There was no protein sources × supplementation frequency interaction for any of the economical and productive performance traits. The protein sources didn't affect the daily average gain, but the frequency of supply affected performance, which was better in the animals under supplementation at three times a week (0.670 kg /day. The highest economic return was obtained with the offer of supplement with cottonseed meal three times a week. The frequency of supplementation affect the nutrients intake, while the protein source of the supplement had effect only on the ethereal extract intake, which was higher in the animals that consumed the supplement with cottonseed meal. The supplement with high energy cottonseed meal provided higher digestibility of diet crude protein. The supply of supplement three times a week, not only reduces the costs of supplementation, but it possibilities a higher performance than the one obtained with daily supplementation. The use of higher energy cottonseed meal in multiple supplements replacing soybean meal is satisfactory mainly under economical point of view.

  11. Seasonal trends of biogenic terpene emissions.

    Science.gov (United States)

    Helmig, Detlev; Daly, Ryan Woodfin; Milford, Jana; Guenther, Alex

    2013-09-01

    Biogenic volatile organic compound (BVOC) emissions from six coniferous tree species, i.e. Pinus ponderosa (Ponderosa Pine), Picea pungens (Blue Spruce), Pseudotsuga menziesii (Rocky Mountain Douglas Fir) and Pinus longaeva (Bristlecone Pine), as well as from two deciduous species, Quercus gambelii (Gamble Oak) and Betula occidentalis (Western River Birch) were studied over a full annual growing cycle. Monoterpene (MT) and sesquiterpene (SQT) emissions rates were quantified in a total of 1236 individual branch enclosure samples. MT dominated coniferous emissions, producing greater than 95% of BVOC emissions. MT and SQT demonstrated short-term emission dependence with temperature. Two oxygenated MT, 1,8-cineol and piperitone, were both light and temperature dependent. Basal emission rates (BER, normalized to 1000μmolm(-2)s(-1) and 30°C) were generally higher in spring and summer than in winter; MT seasonal BER from the coniferous trees maximized between 1.5 and 6.0μgg(-1)h(-1), while seasonal lows were near 0.1μgg(-1)h(-1). The fractional contribution of individual MT to total emissions was found to fluctuate with season. SQT BER measured from the coniferous trees ranged from <0.01 to 0.15μgg(-1)h(-1). BER of up to 1.2μgg(-1)h(-1) of the SQT germacrene B were found from Q. gambelii, peaking in late summer. The β-factor, used to define temperature dependence in emissions modeling, was not found to exhibit discernible growth season trends. A seasonal correction factor proposed by others in previous work to account for a sinusoidal shaped emission pattern was applied to the data. Varying levels of agreement were found between the data and model results for the different plant species seasonal data sets using this correction. Consequently, the analyses on this extensive data set suggest that it is not feasible to apply a universal seasonal correction factor across different vegetation species. A modeling exercise comparing two case scenarios, (1) without and (2

  12. Growing halophytes floating at sea

    Directory of Open Access Journals (Sweden)

    Ricardo Radulovich

    2017-11-01

    Full Text Available Freshwater shortages are increasingly limiting both irrigated and rainfed agriculture. To expand possibilities for controlled plant production without using land nor freshwater, we cultivated potted halophytes floating at sea that were provided with rain- and seawater. Plantlets of two mangroves (Avicennia germinans and Rhizophora mangle and plants of two herbaceous species, sea purslane (Sesuvium portulacastrum and salt couch grass (Sporobolus virginicus were grown in near-coastal tropical Pacific waters of Costa Rica for 733 days. There were a total of 504 rainless days, including two dry periods of ca. 150 d long each, evidencing prolonged and exclusive reliance on seawater. Pots with a sandy soil mixture and the transplanted plants were placed on low-cost wooden floating rafts with their lower end perforated and immersed for capillary rise of water. Free seawater entry and exit through the bottom from bobbing with waves, which also occasionally added water from the top, effectively controlled soil salinity build-up even during the rainless seasons. Continuous leaching made necessary frequent fertilizer addition. No water deficit symptoms were observed and midday canopy temperature during rainless periods was not significantly different between species or from air temperature. With all-year-round growth, height increase of mangrove plantlets ranged from 208.1 to 401.5 mm yr−1. Fresh biomass production of sea purslane and the grass was 10.9 and 3.0 kg m−2 yr−1 respectively. High yield, edibility and protein content of 10.2% dry weight established sea purslane as a potential crop. While further research is needed, the method evidenced to be a viable plant production option of potentially far-reaching applications.

  13. Infection Dynamics on Growing Networks

    Science.gov (United States)

    Lai, Ying-Cheng; Liu, Zonghua; Ye, Nong

    We consider the entire spectrum of architectures for large, growing, and complex networks, ranging from being heterogeneous (scale-free) to homogeneous (random or small-world), and investigate the infection dynamics by using a realistic three-state epidemiological model. In this framework, a node can be in one of the three states: susceptible (S), infected (I), or refractory (R), and the populations in the three groups are approximately described by a set of nonlinear differential equations. Our heuristic analysis predicts that, (1) regardless of the network architecture, there exists a substantial fraction of nodes that can never be infected, and (2) heterogeneous networks are relatively more robust against spread of infection as compared with homogeneous networks. These are confirmed numerically. We have also considered the problem of deliberate immunization for preventing wide spread of infection, with the result that targeted immunization can be quite effective for heterogeneous networks. We believe these results are important for a host of problems in many areas of natural science and engineering, and in social sciences as well.

  14. Case grows for climate change

    Energy Technology Data Exchange (ETDEWEB)

    Hileman, B.

    1999-08-09

    In the four years since the IPCC stated that 'the balance of evidence suggests a discernible human influence on global climate', evidence for anomalous warming has become more compelling, and as a result scientists have become more concerned that human-induced climate change has already arrived. The article summarises recent extra evidence on global temperatures, carbon dioxide measurements, ice shelf breakup, coral bleaching, unstable climates and improved climate models. At the time of the Kyoto conference, the US became keen on the idea that enhancing forest and soil carbon sequestration was a good way to offset emissions reduction targets. Congress is however under the opinion on that the Kyoto protocol presents a threat to the US economy, and senate is very unlikely to ratify the protocol during the Clinton Administration. The debate as to whether the US government should mandate major emission reduction or wait for more scientific certainty may continue for a number of years, but, growing concern of scientists and the public for the harmful effects of climate change may cause a change. 4 figs., 8 photos.

  15. Growing and evolving soft robots.

    Science.gov (United States)

    Rieffel, John; Knox, Davis; Smith, Schuyler; Trimmer, Barry

    2014-01-01

    Completely soft and flexible robots offer to revolutionize fields ranging from search and rescue to endoscopic surgery. One of the outstanding challenges in this burgeoning field is the chicken-and-egg problem of body-brain design: Development of locomotion requires the preexistence of a locomotion-capable body, and development of a location-capable body requires the preexistence of a locomotive gait. This problem is compounded by the high degree of coupling between the material properties of a soft body (such as stiffness or damping coefficients) and the effectiveness of a gait. This article synthesizes four years of research into soft robotics, in particular describing three approaches to the co-discovery of soft robot morphology and control. In the first, muscle placement and firing patterns are coevolved for a fixed body shape with fixed material properties. In the second, the material properties of a simulated soft body coevolve alongside locomotive gaits, with body shape and muscle placement fixed. In the third, a developmental encoding is used to scalably grow elaborate soft body shapes from a small seed structure. Considerations of the simulation time and the challenges of physically implementing soft robots in the real world are discussed.

  16. Pediatric Ovarian Growing Teratoma Syndrome

    Directory of Open Access Journals (Sweden)

    Rebecca M. Rentea

    2017-01-01

    Full Text Available Ovarian immature teratoma is a germ cell tumor that comprises less than 1% of ovarian cancers and is treated with surgical debulking and chemotherapy depending on stage. Growing teratoma syndrome (GTS is the phenomenon of the growth of mature teratoma elements with normal tumor markers during or following chemotherapy for treatment of a malignant germ cell tumor. These tumors are associated with significant morbidity and mortality due to invasive and compressive growth as well as potential for malignant transformation. Current treatment modality is surgical resection. We discuss a 12-year-old female who presented following resection of a pure ovarian immature teratoma (grade 3, FIGO stage IIIC. Following chemotherapy and resection of a pelvic/liver recurrence demonstrating mature teratoma, she underwent molecular genetics based chemotherapeutic treatment. No standardized management protocol has been established for the treatment of GTS. The effect of chemotherapeutic agents for decreasing the volume of and prevention of expansion is unknown. We review in detail the history, diagnostic algorithm, and previous reported pediatric cases as well as treatment options for pediatric patients with GTS.

  17. [Growing old differently: Transdisciplinary perspective].

    Science.gov (United States)

    Zimmermann, H-P

    2015-04-01

    Growing old differently: the phrase is intended to call something other to mind than merely the fact that images and forms of old age and aging have multiplied and diversified to an enormous extent. The suggestion put forward here is that otherness (as opposed to mere differences) should be positively reinforced. In other words, it is not just a matter of noting different forms of old age and aging but more than this, of seeking out opportunities for aging differently. In order to explore this, the article follows an older strand of theory, which has recently come to be frequently quoted in gerontology: the phenomenology of difference as reasoned analytically by Lévinas and Sartre and applied to gerontology by Améry and de Beauvoir. Here, opportunities for aging crucially depend on the way we look at it, how we observe and describe it and not least, how gerontology frames it. A distinction is made between two perspectives and their associated consequences for old age: alienation and alterity. Alienation means looking at old age above all as a disconcerting "other", as a perplexing, problematic deviation from the norm of vitality. Alterity, by contrast, refers to different options for living life in old age: options to be explored and opened up in contradistinction to cultural or academic alienation. Not least, the article appeals for diversity in scholarly approaches and for cross-disciplinary perspectives.

  18. Determining wetland spatial extent and seasonal variations of the ...

    African Journals Online (AJOL)

    This study, done in the Witbank Dam Catchment in Mpumalanga Province of South ... importance of protecting and restoring wetlands by including .... weathered aquifer, is an important source of water in the sub-catchment. The geology within the catchment consists of igneous and metamorphosed rocks, with occurrences.

  19. Menopausal women's positive experience of growing older

    DEFF Research Database (Denmark)

    Hvas, Lotte

    2006-01-01

    This paper aims to describe menopausal women's positive experience of growing older and becoming middle-aged.......This paper aims to describe menopausal women's positive experience of growing older and becoming middle-aged....

  20. Testing for seasonality

    NARCIS (Netherlands)

    Ph.H.B.F. Franses (Philip Hans)

    1992-01-01

    textabstractThis paper proposes a general-to-simple test procedure for the presence of seasonal patterns in time series, which is based on tests for parameter restrictions in a general periodic model. The method is illustrated for the U.K. stock price index and the U.S. CLI index.

  1. Warning Signs: Seasonal Flu

    Centers for Disease Control (CDC) Podcasts

    2010-09-29

    In this podcast, Dr. Joe Bresee describes the main symptoms of seasonal flu and when it is serious enough to seek medical help.  Created: 9/29/2010 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 9/29/2010.

  2. The Hungry Season

    African Journals Online (AJOL)

    start to go some way towards addressing this fundamental question. A delightful animation of The Hungry Season, commissioned by Leonie Joubert and funded by the University of Cape Town's Criminology. Department and the Embassy of Finland, is available online at http://www.youtube.com/ watch?v=iX77NZttLKo.

  3. Take Three: Seasonal Flu

    Centers for Disease Control (CDC) Podcasts

    2010-09-29

    In this podcast, Dr. Joe Bresee describes how to keep from getting seasonal flu and spreading it to others by taking these three steps.  Created: 9/29/2010 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 9/29/2010.

  4. Seasonal Influenza: An Overview

    Science.gov (United States)

    Li, Christina; Freedman, Marian

    2009-01-01

    Seasonal influenza is a major cause of morbidity and mortality in the United States. It also has major social and economic consequences in the form of high rates of absenteeism from school and work as well as significant treatment and hospitalization costs. In fact, annual influenza epidemics and the resulting deaths and lost days of productivity…

  5. Teaching Science: Eclipse Seasons.

    Science.gov (United States)

    Leyden, Michael B.

    1995-01-01

    Demonstrates the need for a three-dimensional model as an aid for teaching students why eclipses do not occur every two weeks, as falsely indicated by two-dimensional models such as books, chalkboards, and computer screens. Describes procedure to construct the model. Indicates question related to seasons likely to arise from such a model and…

  6. Overcoming Seasonal Affective Disorder.

    Science.gov (United States)

    Leahy, Laura G

    2017-11-01

    Seasonal affective disorder (SAD) significantly impacts the lives of individuals around the world. The mood fluctuations that occur are not only exhibited during the winter months but also during the spring and summer. The key to identifying SAD is the distinct seasonal onset and spontaneous remission of symptoms over the course of a season. Nurses are in a unique position to identify the symptoms of SAD and offer treatment recommendations to reduce the negative impact of these seasonal mood fluctuations. As holistic health care practitioners, nurses provide patient education regarding healthy lifestyle interventions, which can aid in minimizing the disruptive symptoms of SAD. Advanced practice nurses can offer pharmacotherapy interventions to address symptoms contributing to the individual's inability to function across domains-individual, family, and social. Finally, after reading the article, nurses of all disciplines will have a better understanding of the evidence-based bright light therapy (also known as light box therapy) and how to incorporate this treatment when caring for patients with SAD. [Journal of Psychosocial Nursing and Mental Health Services, 55(11), 10-14.]. Copyright 2017, SLACK Incorporated.

  7. Antiviral Drugs: Seasonal Flu

    Centers for Disease Control (CDC) Podcasts

    2010-09-29

    In this podcast, Dr. Joe Bresee explains the nature of antiviral drugs and how they are used for seasonal flu.  Created: 9/29/2010 by National Center for Immunization and Respiratory Diseases (NCIRD).   Date Released: 9/29/2010.

  8. Seasonal Affective Disorder (SAD)

    Science.gov (United States)

    ... and making you feel moody. Less often, SAD causes depression in the spring or early summer. Treatment for ... play a role in SAD. Reduced sunlight can cause a drop in serotonin that may trigger depression. Melatonin levels. The change in season can disrupt ...

  9. Bariatric amputee: A growing problem?

    Science.gov (United States)

    Kulkarni, Jai; Hannett, Dominic P; Purcell, Steven

    2015-06-01

    This study reviewed prevalence of patients with lower limb amputations with above normal weight profile, with body mass index over 25, in seven disablement services centres managing their amputee rehabilitation in the United Kingdom. To review two clinical standards of practice in amputee rehabilitation. Ambulant lower limb amputees should have their body weight recorded on an electronic information system, with identification of cohort with body weight >100 kg. Lower limb amputees to be provided with suitable weight-rated prosthesis. Observational study of clinical practice. Data were collected from the Clinical Information Management Systems. Inclusion criteria--subjects were ambulant prosthetic users with some prosthetic intervention in the last 5 years and had at least one lower limb amputation. In 96% of patients, the weight record profile was maintained. In addition, 86% were under 100 kg, which is the most common weight limit of prosthetic componentry. Of 15,204 amputation levels, there were 1830 transfemoral and transtibial sites in users with body weight over 100 kg. In 60 cases, the prosthetic limb build was rated to be below the user body weight. In 96% of our patients, body weight was documented, and in 97%, the prosthetic limb builds were within stated body weight limits, but this may not be the case in all the other disablement services centres in the United Kingdom. Also, the incidence of obesity in the United Kingdom is a growing problem, and the health issues associated with obesity are further compounded in the amputee population. Prosthetic componentry has distinct weight limits which must be considered during prescription. As people with amputation approach the limits of specific components, clinicians are faced with the challenge of continued provision in a safe and suitable manner. This article reviews the amputee population and the current national profile to consider trends in provision and the incidence of these challenges. © The

  10. Seasonal variation in phytochemicals and antioxidant activities in ...

    African Journals Online (AJOL)

    The levels of all phytochemicals and antioxidant activity were significantly influenced by cultivar (C), plant part (P), and growing season (S). Among the glucosinolates, glucoraphanin and glucobrassicin were the major constituents. The highest total glucosinolate content was found in the florets of plants grown in both ...

  11. SEASONAL COURSE OF ISOPRENE EMISSIONS FROM A MIDLATITUDE DECIDUOUS FOREST

    Science.gov (United States)

    Continuous measurements of whole canopy isoprene emissions over an entire growing season are reported from Harvard Forest (42E32'N, 72E11'W). Emissions were calculated from the ratio of observed CO2 flux and gradient multiplied by the observed hydrocarbon gradients. In summer 199...

  12. A method to identify potential cold-climate vine growing sites

    DEFF Research Database (Denmark)

    Olsen, Jørgen L; Olesen, Asger; Breuning-Madsen, Henrik

    2011-01-01

    A method for surveying the suitability of cold climate vine growing sites in Denmark is presented with focus on limiting growth parameters. The four most important parameters are identified on the basis of literary studies and discussions with approximately 150 vine growers in Denmark. These are: i......) Sum of growing degree days (SDD), ii) Risk of frost damage, iii) Number of sunshine hours during growth season, and iv) Soil drainage. A two-step method based on GIS and already existing climate, soil, and topographic data was implemented. First the most suitable areas in Denmark for vine growing were...

  13. Growing spearmint, thyme, oregano, and rosemary in Northern Wyoming using plastic tunnels

    Science.gov (United States)

    Growing perennial herbs in northern climate such as Northern Wyoming is a challenge. Due to short frost-free period, high wind, and inclement weather it is impossible to harvest any herbs twice a year (summer and late fall) without using any form of season extension methods. Hence, we set up an expe...

  14. Soil K Status and K Requirement of Potato Growing on Different ...

    African Journals Online (AJOL)

    An experiment was conducted in 2005/06 and 2006/07 cropping seasons on Nitosols, Acrisols and Luvisols of Western Amhara to investigate the inherent soil K status and K requirement of potato growing on ·these soils. The field experiments were conduckd in Yilmana Densa (West Gojjam Zone), Farta (South Gondar ...

  15. Assessing the potentials of growing Samcot 9 Cotton variety in Kano ...

    African Journals Online (AJOL)

    A Completely randomized field experiment with nine replications was conducted in the North, South and Central Agricultural zones of Kano State during the 2004 cotton growing season with a control in Katsina state, a cotton producing area, with the object of assessing the potentials of the profitable production of the ...

  16. Seasonal scouting of weeds in a sugarbeet field in Mashhad

    Directory of Open Access Journals (Sweden)

    azita ashrafi

    2009-06-01

    Full Text Available Weed scouting is an important part of integrated weed management system. In order to evaluate weed emergence pattern and management efficiency on weed populations, a 2 ha sugarbeet field in Mashhad was selected and evaluated during 2002 growing season. Weeds were identified and counted at 441 points at the intersection of a 7m by 7m grid within 0.15 m2 quadrates. The evaluations were done 3 times [pre management (1 and post management (2]. Geostatistical techniques (kriging were used to analyze the spatial structure of weeds and dynamics of weed patches. 34 weed species were observed across the field. Wide ranges of weeds were observed during growing season including, winter annual (e. g. Sinapis arvensis and Fumaria officinalis, summer annual (e. g. Echinochloa crus-galli, biennial (Dacus caraota and perennal (e. g. Convolvulus arvensis. Solanum nigrum, Chenopodium album, Amaranthus spp., Convolvulus arvensis, Polygonum aviculare and Echinochloa crus-galli were the common weeds over growing season. In early growing season, Solanum nigrum with 404.71 seedlings per m2 was present in all samples constituted 81.32% of weed community, but in 2nd and 3rd sampling time, Convolvulus arvensis was the dominant species with 33.29% and 29.26% of weed community. Relative density percentage of perennial and grassy weeds (generally C4 species was increased over the season but the relative density percentage of broadleaf annual weeds was decreased. Main locations of weed emergence were persisted as elliptical patches east ward and west ward of field over the season. The results of this study indicated that scouting and understanding of weed emergence behavior could be used to design effective strategies of weed management.

  17. Nutrient uptake and distribution in young Pinot noir grapevines over two seasons

    Science.gov (United States)

    The seasonal timing of biomass and nutrient uptake and distribution among different vine organs was determined over two growing seasons in 4-year-old Pinot noir grapevines carrying their first full crop and grown in field microplots. Vines were fertilized in spring and the biomass and nutrient conte...

  18. Vaccination against seasonal flu

    CERN Multimedia

    2015-01-01

    The Medical Service once again recommends you to get your annual flu vaccination for the year.   Vaccination is the most effective way of avoiding the illness and any serious consequences and protecting those around you. The flu can have especially serious consequences for people with chronic conditions (diabetes, cardio-vascular disease, etc.), pregnant women, infants, and people over 65 years of age. Remember, anyone working on the CERN site who wishes to be vaccinated against seasonal flu should go to the Infirmary (Building 57, ground floor) with their vaccine. The Medical Service will issue a prescription on the day of the vaccination for the purposes of reimbursement by UNIQA. NB: The Medical Service cannot provide this vaccination service for family members or retired members of the personnel. For more information: • The "Seasonal flu" flyer by the Medical Service • Recommendations of the Swiss Federal Office of Public...

  19. Vaccination against seasonal influenza

    CERN Multimedia

    DG Unit

    2009-01-01

    As every year, the Medical Service is taking part in the campaign to promote vaccination against seasonal influenza. Vaccination against seasonal influenza is especially recommended for people suffering from chronic lung, cardio-vascular or kidney conditions or diabetes, for those recovering from a serious illness or surgical operation and for everyone over the age of 65. The influenza virus is transmitted by air and contact with contaminated surfaces, hence the importance of washing hands regularly with soap and / or disinfection using a hydro-alcoholic solution. From the onset of symptoms (fever> 38°, chills, cough, muscle aches and / or joint pain, fatigue) you are strongly recommended to stay at home to avoid spreading the virus. In the present context of the influenza A (H1N1) pandemic, it is important to dissociate these two illnesses and emphasise that the two viruses and the vaccines used to combat them are quite different and that protection against one will not pr...

  20. Summer season | Cafeteria closures

    CERN Multimedia

    2013-01-01

    Please note the following cafeteria closures over the summer season: Bldg. 54 closed from 29/07/2013 to 06/09/2013. Bldg. 13: closed from 13/07/2013 to 06/09/2013. Restaurant No. 2, table service (brasserie and restaurant): closed from 01/08/2013 to 06/09/2013. Bldg. 864: closed from 29/07/2013 to 06/09/2013. Bldg. 865: closed from 29/07/2013 to 06/09/2013.

  1. Heartbeat of the Season

    National Research Council Canada - National Science Library

    Sandra Tunajek

    2009-01-01

    ... sounds of the season. It can be tiring and even annoying-and yet, it is the heartbeat of holidays. Along with the candy canes and mistletoe, there we are surrounded, day and night, by Christmas carols, intended to put us in a festive mood. In the six weeks running up to Christmas, individuals who work in environments that play background music will hear "Ji...

  2. Winter climate change affects growing-season soil microbial biomass and activity in northern hardwood forests

    Science.gov (United States)

    Jorge Durán; Jennifer L. Morse; Peter M. Groffman; John L. Campbell; Lynn M. Christenson; Charles T. Driscoll; Timothy J. Fahey; Melany C. Fisk; Myron J. Mitchell; Pamela H. Templer

    2014-01-01

    Understanding the responses of terrestrial ecosystems to global change remains a major challenge of ecological research. We exploited a natural elevation gradient in a northern hardwood forest to determine how reductions in snow accumulation, expected with climate change, directly affect dynamics of soil winter frost, and indirectly soil microbial biomass and activity...

  3. Copper Root Pruning and Container Cavity Size Influence Longleaf Pine Growth through Five Growing Seasons

    Science.gov (United States)

    James D. Haywood; Shi-Jean Susana Sung; Mary Anne Sword Sayer

    2012-01-01

    However, type and size of container can influence field performance. In this study, longleaf pine seedlings were grown in Beaver Plastics Styroblocks either without a copper treatment (Superblock) or with a copper oxychloride coating (Copperblock) and with three sizes of cavities that were 60, 108, and 164 ml. Seedlings from the six container types (two types of...

  4. Growing Season Definition and Use in Wetland Delineation: A Literature Review

    Science.gov (United States)

    2010-08-01

    themoperiodism. Forestry Science 12: 276–283. Henry, H. A. L. 2007. Soil freeze–thaw cycle experiments: Trends, methodological weaknesses and suggested...Turner, F. T., and W. H. Patrick. 1968. Chemical changes in waterlogged soil as a result of oxygen depletion. Transactions of the Ninth Congress Soil

  5. Pesticide Impact Assessment in Tule Lake and Lower Klamath National Wildlife Refuges, 1998 - 2000 Growing Season

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Tule Lake and the adjacent Lower Klamath National Wildlife Refuges (TLNWR and LKNWR) serve as key spring/fall staging and overwintering areas for Pacific Flyway...

  6. Impacts of genetic line, gender and season on feeding behavior of grow-finish swine

    Science.gov (United States)

    Feeding behavior contains important information that can enable producers to better manage livestock. A study was conducted to quantify these impacts. Data were collected on barrows and gilts (n = 931) from 3 different genetic lines (Landrace x Yorkshire material line with three different sire bree...

  7. Effects of warming on Potamogeton crispus growth and tissue stoichiometry in the growing season

    NARCIS (Netherlands)

    Zhang, P.; Bakker, E.S.; Zhang, M.; Xu, J.

    2016-01-01

    Increased water temperature due to climate change may affect macrophyte phenology and nutrient content. In experimentally heated mesocosms the emergence and growth of Potamogeton crispus shoots under ambient and increased temperatures (+4.5 °C) were tracked over 55 days. At the end of the experiment

  8. Sorghum starch properties as affected by growing season, hybrid, and kernel maturity

    Science.gov (United States)

    Starch is a widely used component in the food, feed, and biofuel industries. Critical components in the functionality of a starch in a food or industrial system are the thermal properties. The objective of this study was to evaluate the physical and chemical changes that occur in sorghum starch du...

  9. Embryo dune development drivers: beach morphology, growing season precipitation, and storms

    NARCIS (Netherlands)

    Puijenbroek, van M.E.B.; Limpens, J.; Groot, de Alma; Riksen, M.J.P.M.; Gleichman, J.M.; Slim, P.A.; Dobben, van H.F.; Berendse, F.

    2017-01-01

    For development of embryo dunes on the highly dynamic land–sea boundary, summer growth and the absence of winter erosion are essential. Other than that, however, we know little about the specific conditions that favour embryo dune development. This study explores the boundary conditions for early

  10. A Psychological Model Of Scenic Beauty By Silvicultural Treatment Two Growing Seasons After Harvest

    Science.gov (United States)

    Ying-Hung Li; Victor A. Rudis; Theresa A. Herrick

    2004-01-01

    Abstract - This study estimated summer scenic beauty and associated psychological attributes of scenes depicting uncut and several cutting regimes within shortleaf pine-hardwood forests on national forests. Images were captured in the summer of 1994 in nine treated and three comparable untreated stands in the Ouachita Mountains of Arkansas....

  11. Response of Saw Palmetto to Three Herbicides During the First Growing Season

    Science.gov (United States)

    J.L. Michael

    1980-01-01

    Trimec 881 and 823 (mixture of 2,4-D; MCPP and dicamba in 2:1:0.l and 1:1:0.25 ratio respectively) and trichlopyr ester were evaluated for effectiveness against saw palmetto, Serenoa repens (Bartram) Small, when they were applied at three rates in April, June, and August. Herbicides were most effective with April applicatiorr, least effective in...

  12. PRODUCTIVITY OF GROWING PONDS WHEN APPLYING THE BACTERIAL FERTILIZER «PHOSPHOBAKTERIN»

    Directory of Open Access Journals (Sweden)

    Т. Hryhorenko

    2017-09-01

    Full Text Available Purpose. To investigate the effect of the bacterial fertilizer "Phosphobacterin" on the formation of the hydrochemical regime, development of the natural food supply and fish productivity in the growing ponds. Methodology. The work was conducted according to generally accepted hydrochemical,, microbiological, hydrobiological and fish farming methods. Findings The article presents the results of a study of the productivity of growing ponds with different methods of the application of the bacterial fertilizer "Phosphobacterin". It was found that the hydrochemical regime of the experimental ponds was formed under the effect of the source of water supply and measures aimed at intensifying the development of the natural food supply and was favorable for the development of feed organisms and the cultivation of fish seeds. Application of the bacterial fertilizer at the beginning of the growing season along the water pond surface proved to be little effective for increasing the productivity of the pond ecosystem as a whole. A more effective method of increasing biological productivity, including fish productivity of growing ponds, was the application of "Phosphobacterin" during the growing season both on the bed and on the water surface in combination with the organic fertilizer - cattle humus. In the experimental pond under complex fertilization, the average phytoplankton biomass during the growing season was 1.5 times, bacterioplankton 1.1 times, zoobenthos 2.6 times higher, and the obtained total fish productivity was 1.2 times higher than in the control pond (when applying only cattle humus. Originality. The peculiarities of formation of hydrochemical and hydrobiological (phyto-, bacterio-, zooplankton, zoobenthos regimes of growing ponds and the fishery indices are studied, both for bacterial fertilizer "Phosphobacterin" independently and together with the traditional organic fertilizer - cattle humus. Practical value. Based on the obtained results

  13. Vaccination against seasonal influenza

    CERN Multimedia

    GS Department

    2010-01-01

    This year, as usual, the Medical Service is helping to promote vaccination against seasonal influenza. Vaccination against seasonal flu is especially recommended for anyone who suffers from chronic pulmonary, cardio-vascular or kidney disease or diabetes, is recovering from a serious illness or major surgery, or is over 65 years of age. The flu virus is transmitted through the air and through contact with contaminated surfaces, so frequent hand-washing with soap and/or an antiseptic hand wash is of great importance. As soon as the first symptoms appear (fever above 38°, shivering, coughing, muscle and/or joint pains, generalised weakness), you are strongly recommended to stay at home to avoid spreading the virus. Anyone working on the CERN site who wishes to be vaccinated against seasonal flu should go to the Infirmary (Building 57, ground floor), with their dose of vaccine. The Medical Service will issue a prescription on the day of the vaccination for the purposes of reimbursement through UNIQA...

  14. NEW SEASON NEW HOPES: OFF-SEASON OPTIMISM

    Directory of Open Access Journals (Sweden)

    Oguz Ersan

    2017-12-01

    Full Text Available While literature on the relation between on-field sports performance and stock returns is ample, there is very limited evidence on off-season stage. Constituting around 3 months, off-seasons do not only occupy a significant part of the year but also represent totally different characteristics than on-seasons. They lack the periodic, unambiguous news events in on-seasons (match results, instead they are associated with highly uncertain transfer news and rumors. We show that this distinction has several impacts on the stock market performances of soccer clubs. Most notably, off-seasons generate substantially higher (excess returns. After controlling for other variables, the estimated effect of off-season periods is as high as 38.75%, annually. In line with several seminal studies, we link this fact to increased optimism and betting behavior through uncertain periods; and periods prior to the start of a new calendar (in our case, new season. For all of the examined 7 clubs (3 from Italy and 4 from Turkey, mean excess returns over the market are positive (negative in off-seasons (on-seasons. On-seasons are associated with increased trading activity due to more frequent news. Stocks of Italian clubs are evidently more volatile through off-seasons while volatility results for the stocks of Turkish clubs are not consistent.

  15. Seasonal changes of water carbon relations in savanna ecosystems

    Science.gov (United States)

    Kutsch, W. L.; Merbold, L.; Archibald, S.

    2011-12-01

    During evolution plant species have developed different strategies to optimize the water carbon relations. These stratgies summarize to ecosystem properties. As an example we show how tropical and subtropical savannas and woodlands can respond flexibly to changes in temperature and water availability and thus optimize carbon and water fluxes between land surface and atmosphere. Several phenomena are presented and discussed in this overview from African flux sites in Zambia, Burkina Faso and South Africa: Pre-rain leaf development: Many trees developed new leaves before the first rain appeared. As a consequence of this early timing of leaf flush, the phenological increase of photosynthetic capacity (Amax) was steeper than in temperate forests. Mid-term response of conductance and photosynthesis to soil water relations: The regulation of canopy conductance was temporally changing in two ways: changes due to phenology during the course of the growing season and short-term (hours to days) acclimation to soil water conditions. The most constant parameter was water use efficiency. It was influenced by water vapour pressure deficit (VPD) during the day, but the VPD response curve of water usage only changed slightly during the course of the growing season, and decreased by about 30% during the transition from wet to dry season. The regulation of canopy conductance and photosynthetic capacity were closely related. This observation meets recent leaf-level findings that stomatal closure triggers down-regulation of Rubisco during drought. Our results may show the effects of these processes on the ecosystem scale. Furthermore, we observed that the close relationship between stomatal conductance and photosynthesis resulted in different temperature optima of GPP that were close to the average daytime temperature. Adaptation of respiration to rain pulses: Finally, the response of respiration to rain pulses showed changes throughout the growing season. The first rain events early

  16. Flu season and trehalose

    Directory of Open Access Journals (Sweden)

    Robbins RA

    2018-01-01

    Full Text Available Most of us who are practicing medicine know that we are in a very active flu season. This was brought home to me when last week trying to admit a patient to the hospital from the office. She was a bone marrow transplant patient who had severe diarrhea and dehydration probably secondary to C. difficile. Hospital admissions said the patient had to be sent to the Emergency Room because the hospital was full due to the flu epidemic. Nationwide there has been a dramatic increase in the number of hospitalizations due to influenza over the past week from 13.7 to 22.7 per 100,000 (1. Influenza A(H3N2 has been the most common form of influenza reported this season. These viruses are often linked to more severe illness, especially in children and people age 65 years and older. Fortunately, the CDC also says that the flu cases may be peaking. However, at ...

  17. Music season coming soon

    CERN Multimedia

    CERN Bulletin in collaboration with Julio Rosenfeld

    2012-01-01

    On 16 June, CERN’s music season will open with Music on the Lawn. The event is the CERN Music Club’s contribution to the Fete de la Musique and will take place on the terrace of Restaurant 1 from 2 p.m. to 8 p.m. The Hardronic Festival, CERN’s long-running rock festival, will be held on the evenings of 20 and 21 July in Prévessin, on the terrace behind Restaurant 3. If you would like to help with the organisation, please contact the Music Club by e-mail: music.club@cern.ch.   The Canettes Blues Band during the 2011 Hardronic Festival. (© Christoph Balle, 2010). Summer is coming, and along with it comes the music season. CERN will be hosting its two annual rock music concerts: Music on the Lawn and the Hardronic Festival. The two events are organised by the CERN Music Club, which has been sharing the enjoyment of good music with its numerous fans for many years. “Music on the Lawn was originally created so that the members of the Mus...

  18. Vaccination against seasonal influenza

    CERN Multimedia

    SC Unit

    2009-01-01

    As every year, the Medical Service is taking part in the campaign to promote vaccination against seasonal influenza. Vaccination against seasonal influenza is especially recommended for people suffering from chronic lung, cardio-vascular or kidney conditions or diabetes, for those recovering from a serious illness or surgical operation and for everyone over the age of 65. The influenza virus is transmitted by air and contact with contaminated surfaces, hence the importance of washing hands regularly with soap and / or disinfection using a hydro-alcoholic solution. From the onset of symptoms (fever> 38°, chills, cough, muscle aches and / or joint pain, fatigue) you are strongly recommended to stay at home to avoid spreading the virus. In the present context of the influenza A (H1N1) pandemic, it is important to dissociate these two illnesses and emphasise that the two viruses and the vaccines used to combat them are quite different and that protection against one will not provide protection against the...

  19. Magnetically controlled growing rods for scoliosis surgery.

    Science.gov (United States)

    Metkar, Umesh; Kurra, Swamy; Quinzi, David; Albanese, Stephen; Lavelle, William F

    2017-02-01

    Early onset scoliosis can be both a disfiguring as well as a life threatening condition. When more conservative treatments fail, pediatric spinal surgeons are forced to consider operative interventions. Traditionally, these interventions have involved the insertion of a variety of implants into the patient with a limited number of anchor points controlling the spine. In the past, these pediatric patients have had multiple surgeries for elective lengthening of these devices to facilitate their growth while attempting to control the scoliosis. These patients often experience a physical and emotional toll from their multiple repeated surgeries. Growing spine techniques have also had a noted high complication rate due to implant dislodgement and infections. Recently, the development of non-invasively, self-lengthening growing rods has occurred. These devices have the potential to allow for the devices to be lengthened magnetically in a conscious patient in the surgeon's office. Areas covered: This review summarized previously published articles in the English literature using a key word search in PubMed for: 'magnetically controlled growing rods', 'Magec rods', 'magnetic growing rods' and 'growing rods'. Expert commentary: Magnetically controlled growing rods have an advantage over growing rods in lengthening the growing spine in the absence of repetitive surgeries.

  20. (GrOW) Frequently Asked Questions

    International Development Research Centre (IDRC) Digital Library (Canada)

    Alejandra

    How many applications will be shortlisted at the end of the first stage? GrOW envisages that up to 4 selected teams will be asked to submit a full research proposal for review and funding consideration. How is the review process conducted? Upon receiving complete applications, a review process begins by the GrOW team, ...

  1. Predicted responses of arctic and alpine ecosystems to altered seasonality under climate change.

    Science.gov (United States)

    Ernakovich, Jessica G; Hopping, Kelly A; Berdanier, Aaron B; Simpson, Rodney T; Kachergis, Emily J; Steltzer, Heidi; Wallenstein, Matthew D

    2014-10-01

    Global climate change is already having significant impacts on arctic and alpine ecosystems, and ongoing increases in temperature and altered precipitation patterns will affect the strong seasonal patterns that characterize these temperature-limited systems. The length of the potential growing season in these tundra environments is increasing due to warmer temperatures and earlier spring snow melt. Here, we compare current and projected climate and ecological data from 20 Northern Hemisphere sites to identify how seasonal changes in the physical environment due to climate change will alter the seasonality of arctic and alpine ecosystems. We find that although arctic and alpine ecosystems appear similar under historical climate conditions, climate change will lead to divergent responses, particularly in the spring and fall shoulder seasons. As seasonality changes in the Arctic, plants will advance the timing of spring phenological events, which could increase plant nutrient uptake, production, and ecosystem carbon (C) gain. In alpine regions, photoperiod will constrain spring plant phenology, limiting the extent to which the growing season can lengthen, especially if decreased water availability from earlier snow melt and warmer summer temperatures lead to earlier senescence. The result could be a shorter growing season with decreased production and increased nutrient loss. These contrasting alpine and arctic ecosystem responses will have cascading effects on ecosystems, affecting community structure, biotic interactions, and biogeochemistry. © 2014 John Wiley & Sons Ltd.

  2. Meteorological Influences on the Seasonality of Lyme Disease in the United States

    Science.gov (United States)

    Moore, Sean M.; Eisen, Rebecca J.; Monaghan, Andrew; Mead, Paul

    2014-01-01

    Lyme disease (Borrelia burgdorferi infection) is the most common vector-transmitted disease in the United States. The majority of human Lyme disease (LD) cases occur in the summer months, but the timing of the peak occurrence varies geographically and from year to year. We calculated the beginning, peak, end, and duration of the main LD season in 12 highly endemic states from 1992 to 2007 and then examined the association between the timing of these seasonal variables and several meteorological variables. An earlier beginning to the LD season was positively associated with higher cumulative growing degree days through Week 20, lower cumulative precipitation, a lower saturation deficit, and proximity to the Atlantic coast. The timing of the peak and duration of the LD season were also associated with cumulative growing degree days, saturation deficit, and cumulative precipitation, but no meteorological predictors adequately explained the timing of the end of the LD season. PMID:24470565

  3. Cold season emissions dominate the Arctic tundra methane budget.

    Science.gov (United States)

    Zona, Donatella; Gioli, Beniamino; Commane, Róisín; Lindaas, Jakob; Wofsy, Steven C; Miller, Charles E; Dinardo, Steven J; Dengel, Sigrid; Sweeney, Colm; Karion, Anna; Chang, Rachel Y-W; Henderson, John M; Murphy, Patrick C; Goodrich, Jordan P; Moreaux, Virginie; Liljedahl, Anna; Watts, Jennifer D; Kimball, John S; Lipson, David A; Oechel, Walter C

    2016-01-05

    Arctic terrestrial ecosystems are major global sources of methane (CH4); hence, it is important to understand the seasonal and climatic controls on CH4 emissions from these systems. Here, we report year-round CH4 emissions from Alaskan Arctic tundra eddy flux sites and regional fluxes derived from aircraft data. We find that emissions during the cold season (September to May) account for ≥ 50% of the annual CH4 flux, with the highest emissions from noninundated upland tundra. A major fraction of cold season emissions occur during the "zero curtain" period, when subsurface soil temperatures are poised near 0 °C. The zero curtain may persist longer than the growing season, and CH4 emissions are enhanced when the duration is extended by a deep thawed layer as can occur with thick snow cover. Regional scale fluxes of CH4 derived from aircraft data demonstrate the large spatial extent of late season CH4 emissions. Scaled to the circumpolar Arctic, cold season fluxes from tundra total 12 ± 5 (95% confidence interval) Tg CH4 y(-1), ∼ 25% of global emissions from extratropical wetlands, or ∼ 6% of total global wetland methane emissions. The dominance of late-season emissions, sensitivity to soil environmental conditions, and importance of dry tundra are not currently simulated in most global climate models. Because Arctic warming disproportionally impacts the cold season, our results suggest that higher cold-season CH4 emissions will result from observed and predicted increases in snow thickness, active layer depth, and soil temperature, representing important positive feedbacks on climate warming.

  4. Trends and seasonality in stream water chemistry in two moorland catchments of the Upper River Wye, Plynlimon

    Directory of Open Access Journals (Sweden)

    B. Reynolds

    1997-01-01

    Full Text Available Stream water chemistry in the Cyff and Gwy subcatchments within the headwaters of the River Wye has been monitored regularly since 1980. In the Gwy, which is a predominantly semi-natural grassland catchment, land use has remained relatively static over the monitoring period, whilst the Cyff catchment is more buffered because of base cation inputs from agricultural improvement and ground water sources. Using a variety of statistical techniques, the long-term data are examined for evidence of trends after eliminating seasonal effects. The results highlight some of the difficulties associated with the analysis of longterm water quality data which show considerable variability over a variety of timescales. Some of this variability can be explained in terms of hydrochemical responses to climatic extremes and episodic events such as large atmospheric inputs of seasalts. The long-term fluctuations in solute concentration underline the continuing need for maintaining consistent long-term monitoring at sensitive upland sites if underlying trends related to gradual changes in pollutant deposition or climate are to be detected with any certainty.

  5. A method to identify potential cold-climate vine growing sites

    DEFF Research Database (Denmark)

    Olsen, Jørgen Lundegaard; Olesen, Asger; Breuning-Madsen, Henrik

    2011-01-01

    A method for surveying the suitability of cold climate vine growing sites in Denmark is presented with focus on limiting growth parameters. The four most important parameters are identified on the basis of literary studies and discussions with approximately 150 vine growers in Denmark. These are: i......) Sum of growing degree days (SDD), ii) Risk of frost damage, iii) Number of sunshine hours during growth season, and iv) Soil drainage. A two-step method based on GIS and already existing climate, soil, and topographic data was implemented. First the most suitable areas in Denmark for vine growing were...... located on the basis of nation-wide climatic data on the sum of degree days and risk of frost. Within the most suitable areas a detailed survey of the amount of sunshine, topography, drainage and soil was carried out on the Røsnæs peninsula in north western Zealand, and eight well-suited vine growing...

  6. with short selling season

    Directory of Open Access Journals (Sweden)

    Moutaz Khouja

    2005-01-01

    deciding on the production levels for a product that has a very short selling season. The firm has a full period to produce and meet a lumpy demand which occurs at the end of the period. The product is no longer demanded after the end of the period. A constant production rate which minimizes average unit cost may increase holding costs. Varying the production rate at discrete points in time may increase production costs but may also decrease holding costs. In addition, allowing changes in the production rate enables the incorporation of forecast revisions into the production plan. Therefore, the best production plan depends on the flexibility of the production system and on the holding cost. In this paper, we formulate and solve a model of this production planning problem. Two models are developed to deal with two types of the average unit cost function. Numerical examples are used to illustrate the results of the model.

  7. Microsatellite Primers for Fungus-Growing Ants

    DEFF Research Database (Denmark)

    Villesen Fredsted, Palle; Gertsch, Pia J.; Boomsma, Jacobus Jan (Koos)

    2002-01-01

    We isolated five polymorphic microsatellite loci from a library of two thousand recombinant clones of two fungus-growing ant species, Cyphomyrmex longiscapus and Trachymyrmex cf. zeteki. Amplification and heterozygosity were tested in five species of higher attine ants using both the newly...... developed primers and earlier published primers that were developed for fungus-growing ants. A total of 20 variable microsatellite loci, developed for six different species of fungus-growing ants, are now available for studying the population genetics and colony kin-structure of these ants....

  8. Microsatellite primers for fungus-growing ants

    DEFF Research Database (Denmark)

    Villesen, Palle; Gertsch, P J; Boomsma, JJ

    2002-01-01

    We isolated five polymorphic microsatellite loci from a library of two thousand recombinant clones of two fungus-growing ant species, Cyphomyrmex longiscapus and Trachymyrmex cf. zeteki. Amplification and heterozygosity were tested in five species of higher attine ants using both the newly...... developed primers and earlier published primers that were developed for fungus-growing ants. A total of 20 variable microsatellite loci, developed for six different species of fungus-growing ants, are now available for studying the population genetics and colony kin-structure of these ants....

  9. Vegetation response to rainfall seasonality and interannual variability in tropical dry forests

    Science.gov (United States)

    Feng, X.; Silva Souza, R. M.; Souza, E.; Antonino, A.; Montenegro, S.; Porporato, A. M.

    2015-12-01

    We analyzed the response of tropical dry forests to seasonal and interannual rainfall variability, focusing on the caatinga biome in semi-arid in Northeast Brazil. We selected four sites across a gradient of rainfall amount and seasonality and analyzed daily rainfall and biweekly Normalized Difference Vegetation Index (NDVI) in the period 2000-2014. The seasonal and interannual rainfall statistics were characterized using recently developed metrics describing duration, location, and intensity of wet season and compared them with those of NDVI time series and modelled soil moisture. A model of NDVI was also developed and forced by different rainfall scenarios (combination amount of rainfall and duration of wet season). The results show that the caatinga tends to have a more stable response characterized by longer and less variable growing seasons (of duration 3.1±0.1 months) compared to the rainfall wet seasons (2.0±0.5 months). Even for more extreme rainfall conditions, the ecosystem shows very little sensitivity to duration of wet season in relation to the amount of rainfall, however the duration of wet season is most evident for wetter sites. This ability of the ecosystem in buffering the interannual variability of rainfall is corroborated by the stability of the centroid location of the growing season compared to the wet season for all sites. The maximal biomass production was observed at intermediate levels of seasonality, suggesting a possible interesting trade-off in the effects of intensity (i.e., amount) and duration of the wet season on vegetation growth.

  10. BLOOD METABOLIC HORMONES AND LEPTIN IN GROWING LAMBS

    Directory of Open Access Journals (Sweden)

    Zvonko Antunović

    2010-12-01

    Full Text Available The aim of this paper is to determine the concentration of blood metabolic hormones and leptin levels in growing lambs. The research was carried out on Tsigai lambs in two periods (suckling and fattening during the winter feeding season. Lambs were suckling and ate a food mixture and alfalfa hay ad libitum, while during the fattening period they were fed only with the above mentioned mixture and alfalfa hay ad libitum. Their blood was analyzed on 35th and 75th day of age. Concentrations of minsulin, leptin and thyroid hormones were determined in the blood serum of lambs during both periods. In the blood of fattening lambs significantly higher (P0.05 insulin concentrations (1.05 and 0.54 μU/mL, were determined, compared to suckling lambs. A significant strong positive correlation between serum leptin and insulin (r = 0.85, P0.05. The concentration of thyroid hormones did not significantly differ depending on the period of measurement. These changes indicate that the measurement concentrations of metabolic hormones and leptin in blood are very important in order to understand the changes of metabolism and nutrient supply in growing lambs.

  11. Projecting Future Change in Growing Degree Days of Winter Wheat

    Science.gov (United States)

    Ruiz Castillo, N.; Gaitan Ospina, C. F.; Mcpherson, R. A.

    2015-12-01

    Southwest Oklahoma is one of the most productive regions in the Great Plains where winter wheat is produced. To assess the effect of climate change on the growing degree days (GDD) available for winter wheat production, we selected from the CMIP5 archive, two of the best performing Global Climate Models (GCMs) for the region (MIROC5 and CCSM4) to project the future change in GDD under the Representative Concentration Pathway (RCP) 8.5 —a "business as usual" future trajectory for greenhouse gas concentrations. Two quantile mapping downscaling methods were applied to both GCMs to obtain local scale projections. The downscaled outputs were applied to a GDD formula to show the GDD changes between the historical period (1961-2004) and the future period (2006-2098) in terms of mean differences. The results show that at the end of the 2098 growing season, the increase in GDD is expected to be between -2.0 and 6. Depending on the GCM used, Southwest Oklahoma is expected to see an increase in future GDD under the CCSM4 GCM and a mix of increase, no change and decrease under the MIROC5 GCM.

  12. Growing America's Energy Future

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-06-01

    The emerging U.S. bioenergy industry provides a secure and growing supply of transportation fuels, biopower, and bioproducts produced from a range of abundant, renewable biomass resources. Bioenergy can help ensure a secure, sustainable, and economically sound future by reducing U.S. dependence on foreign oil, developing domestic clean energy sources, and generating domestic green jobs. Bioenergy can also help address growing concerns about climate change by reducing greenhouse gas emissions to create a healthier environment for current and future generations.

  13. Global Seasonality of Rotavirus Disease

    Science.gov (United States)

    Patel, Manish M.; Pitzer, Virginia; Alonso, Wladimir J.; Vera, David; Lopman, Ben; Tate, Jacqueline; Viboud, Cecile; Parashar, Umesh D.

    2012-01-01

    Background A substantial number of surveillance studies have documented rotavirus prevalence among children admitted for dehydrating diarrhea. We sought to establish global seasonal patterns of rotavirus disease before widespread vaccine introduction. Methods We reviewed studies of rotavirus detection in children with diarrhea published since 1995. We assessed potential relationships between seasonal prevalence and locality by plotting the average monthly proportion of diarrhea cases positive for rotavirus according to geography, country development, and latitude. We used linear regression to identify variables that were potentially associated with the seasonal intensity of rotavirus. Results Among a total of 99 studies representing all six geographical regions of the world, patterns of year-round disease were more evident in low- and low-middle income countries compared with upper-middle and high income countries where disease was more likely to be seasonal. The level of country development was a stronger predictor of strength of seasonality (P=0.001) than geographical location or climate. However, the observation of distinctly different seasonal patterns of rotavirus disease in some countries with similar geographical location, climate and level of development indicate that a single unifying explanation for variation in seasonality of rotavirus disease is unlikely. Conclusion While no unifying explanation emerged for varying rotavirus seasonality globally, the country income level was somewhat more predictive of the likelihood of having seasonal disease than other factors. Future evaluation of the effect of rotavirus vaccination on seasonal patterns of disease in different settings may help understand factors that drive the global seasonality of rotavirus disease. PMID:23190782

  14. A model to predict the beginning of the pollen season

    DEFF Research Database (Denmark)

    Toldam-Andersen, Torben Bo

    1991-01-01

    In order to predict the beginning of the pollen season, a model comprising the Utah phenoclirnatography Chill Unit (CU) and ASYMCUR-Growing Degree Hour (GDH) submodels were used to predict the first bloom in Alms, Ulttirrs and Berirln. The model relates environmental temperatures to rest completion...... and bud development. As phenologic parameter 14 years of pollen counts were used. The observed datcs for the beginning of the pollen seasons were defined from the pollen counts and compared with the model prediction. The CU and GDH submodels were used as: 1. A fixed day model, using only the GDH model...... for fruit trees are generally applicable, and give a reasonable description of the growth processes of other trees. This type of model can therefore be of value in predicting the start of the pollen season. The predicted dates were generally within 3-5 days of the observed. Finally the possibility of frost...

  15. Seasonality and Photoperiodism in Fungi

    NARCIS (Netherlands)

    Roenneberg, Till; Merrow, Martha

    2001-01-01

    This review gives a retrospective of what is known about photoperiodism in fungi, which is largely based on reports about seasonal spore concentrations. Relatively few species have been investigated under laboratory conditions, so that our knowledge whether seasonal reproduction in fungi is mainly a

  16. Regional-seasonal weather forecasting

    Energy Technology Data Exchange (ETDEWEB)

    Abarbanel, H.; Foley, H.; MacDonald, G.; Rothaus, O.; Rudermann, M.; Vesecky, J.

    1980-08-01

    In the interest of allocating heating fuels optimally, the state-of-the-art for seasonal weather forecasting is reviewed. A model using an enormous data base of past weather data is contemplated to improve seasonal forecasts, but present skills do not make that practicable. 90 references. (PSB)

  17. The effects of genotype and growing conditions on antioxidant capacity, phenolic compounds, organic acid and individual sugars of strawberry.

    Science.gov (United States)

    Gündüz, Kazim; Ozdemir, Emine

    2014-07-15

    In this study, the genotypic and environmental effects for bioactive compounds in strawberries were partitioned. 13 strawberry genotypes from diverse breeding programs were selected. The genotypes were grown in three growing conditions: greenhouse (GH), plastic tunnel (PT) and open-field (OF) for two growing seasons. The results indicated that the genotypes were significantly different for most of the characteristics tested except the ferric reducing ability assay (FRAP) and Trolox-equivalent antioxidant capacity assay (TEAC) in the second growing season, while the growing conditions were only significant for total phenolic content (TPC) and fructose and total sugar content in the first growing season. Genotype had 71% and 72% of the total variance for total monomeric anthocyanin contents (TMA), while it had only 12% and 13% of the variance for TPC in the first and second year of the experiment. Genotype effect was larger than that from the growing conditions for most of the bioactive component variables in the experiment indicated that breeding for bioactive components may be successful. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Monitoring Grassland Tourist Season of Inner Mongolia, China Using Remote Sensing Data

    Directory of Open Access Journals (Sweden)

    Quansheng Ge

    2014-01-01

    Full Text Available Phenology-driven events, such as spring wildflower displays or fall tree colour, are generally appreciated by tourists for centuries around the world. Monitoring when tourist seasons occur using satellite data has been an area of growing research interest in recent decades. In this paper, a valid methodology for detecting the grassland tourist season using remote sensing data was presented. On average, the beginning, the best, and the end of grassland tourist season of Inner Mongolia, China, occur in late June (±30 days, early July (±30 days, and late July (±50 days, respectively. In south region, the grassland tourist season appeared relatively late. The length of the grassland tourist season is about 90 days with strong spatial trend. South areas exhibit longer tourist season.

  19. Influence of the Growing Conditions in the Content of Vitamin C in Diplotaxis erucoides

    OpenAIRE

    Carla GUIJARRO-REAL; Adrián RODRÍGUEZ-BURRUEZO; Jaime PROHENS; Ana M. ADALID-MARTÍNEZ; Ana FITA

    2017-01-01

    Diplotaxis erucoides is an edible plant with potential for marketing. Here, we analysed the influence of the growing conditions in this species, D. tenuifolia and Eruca sativa, and studied the relation among the ascorbic (AA) and dehydroascorbic (DHA) acid forms. Plants were grown in the late winter-spring season under two conditions, greenhouse and field. The contents in AA, DHA and vitamin C (VC) were analysed by HPLC. The content of VC and AA were, in general, remarkable higher in the plan...

  20. NOVA making stuff: Season 2

    Energy Technology Data Exchange (ETDEWEB)

    Leombruni, Lisa [WGBH Educational Foundation, Boston, MA (United States); Paulsen, Christine Andrews [Concord Evaluation Group, Concord, MA (United States)

    2014-12-12

    Over the course of four weeks in fall 2013, 11.7 million Americans tuned in to PBS to follow host David Pogue as he led them in search of engineering and scientific breakthroughs poised to change our world. Levitating trains, quantum computers, robotic bees, and bomb-detecting plants—these were just a few of the cutting-edge innovations brought into the living rooms of families across the country in NOVA’s four-part series, Making Stuff: Faster, Wilder, Colder, and Safer. Each of the four one-hour programs gave viewers a behind-the-scenes look at novel technologies poised to change our world—showing them how basic research and scientific discovery can hold the keys to transforming how we live. Making Stuff Season 2 (MS2) combined true entertainment with educational value, creating a popular and engaging series that brought accessible science into the homes of millions. NOVA’s goal to engage the public with such technological innovation and basic research extended beyond the broadcast series, including a variety of online, educational, and promotional activities: original online science reporting, web-only short-form videos, a new online quiz-game, social media engagement and promotion, an educational outreach “toolkit” for science educators to create their own “makerspaces,” an online community of practice, a series of nationwide Innovation Cafés, educator professional development, a suite of teacher resources, an “Idealab,” participation in national conferences, and specialized station relation and marketing. A summative evaluation of the MS2 project indicates that overall, these activities helped make a significant impact on the viewers, users, and participants that NOVA reached. The final evaluation conducted by Concord Evaluation Group (CEG) confidently concluded that the broadcast, website, and outreach activities were successful at achieving the project’s intended impacts. CEG reported that the MS2 series and website content were

  1. Seasonality constraints to livestock grazing intensity.

    Science.gov (United States)

    Fetzel, Tamara; Havlik, Petr; Herrero, Mario; Erb, Karl-Heinz

    2017-04-01

    Increasing food production is essential to meet the future food demand of a growing world population. In light of pressing sustainability challenges such as climate change and the importance of the global livestock system for food security as well as GHG emissions, finding ways to increasing food production sustainably and without increasing competition for food crops is essential. Yet, many unknowns relate to livestock grazing, in particular grazing intensity, an essential variable to assess the sustainability of livestock systems. Here, we explore ecological limits to grazing intensity (GI; i.e. the fraction of net primary production consumed by grazing animals) by analysing the role of seasonality in natural grasslands. We estimate seasonal limitations to GI by combining monthly net primary production data and a map of global livestock distribution with assumptions on the length of nonfavourable periods that can be bridged by livestock (e.g. by browsing dead standing biomass, storage systems or biomass conservation). This allows us to derive a seasonality-limited potential GI, which we compare with the GI prevailing in 2000. We find that GI in 2000 lies below its potential on 39% of the total global natural grasslands, which has a potential for increasing biomass extraction of up to 181 MtC/yr. In contrast, on 61% of the area GI exceeds the potential, made possible by management. Mobilizing this potential could increase milk production by 5%, meat production by 4% or contribute to free up to 2.8 Mio km² of grassland area at the global scale if the numerous socio-ecological constraints can be overcome. We discuss socio-ecological trade-offs, which may reduce the estimated potential considerably and require the establishment of sound monitoring systems and an improved understanding of livestock system's role in the Earth system. © 2017 John Wiley & Sons Ltd.

  2. Prediction uncertainty in seasonal partial duration series

    DEFF Research Database (Denmark)

    Rasmussen, Peter Funder; Rosbjerg, Dan

    1991-01-01

    -seasonal probability density function of the T year event estimator has been deduced and used in the assessment of the precision of approximate moments. The nonseasonal approach covered both a total omission of seasonality by pooling data from different flood seasons and a discarding of nonsignificant season(s) before...

  3. Seasonal Variations in Color Preference.

    Science.gov (United States)

    Schloss, Karen B; Nelson, Rolf; Parker, Laura; Heck, Isobel A; Palmer, Stephen E

    2017-08-01

    We investigated how color preferences vary according to season and whether those changes could be explained by the ecological valence theory (EVT). To do so, we assessed the same participants' preferences for the same colors during fall, winter, spring, and summer in the northeastern United States, where there are large seasonal changes in environmental colors. Seasonal differences were most pronounced between fall and the other three seasons. Participants liked fall-associated dark-warm colors-for example, dark-red, dark-orange (brown), dark-yellow (olive), and dark-chartreuse-more during fall than other seasons. The EVT could explain these changes with a modified version of Palmer and Schloss' (2010) weighted affective valence estimate (WAVE) procedure that added an activation term to the WAVE equation. The results indicate that color preferences change according to season, as color-associated objects become more/less activated in the observer. These seasonal changes in color preferences could not be characterized by overall shifts in weights along cone-contrast axes. Copyright © 2016 Cognitive Science Society, Inc.

  4. Viewing Seasonality in 8 Megacities at 4 Microns

    Science.gov (United States)

    Tomaszewska, M. A.; Kovalskyy, V.; Small, C.; Henebry, G. M.

    2013-12-01

    the forest 'natural' type showing least seasonal variation and agriculture showing more variation than forest but less than urban. Where the 'natural' type included much exposed soil or dried vegetation (savanna near Nairobi and New Delhi or desert near Cairo), the seasonal dynamic range in the MIR exceeded that of the associated city. However, the interaction of VZA and seasonality was most evident in the agricultural land covers, likely due to exposed cropland soils being gradually covered by the growing canopy when viewed at higher VZAs.

  5. The SGIA and the Common Growing Language

    Directory of Open Access Journals (Sweden)

    Laurentiu CIOVICA

    2011-01-01

    Full Text Available Human or virtual agents are presented in our lives daily. They serve our purposes and represent us in different many situations. Nowadays the number of virtual agents is increasing daily because they are cheaper, faster and more accurate than human agents. Our aim in this article is to define a new type of intelligent agent called SGIA – Self Growing Intelligent Agent and a new defining language for it. The SGIA agent is an intelligent agent with all the common agents’ characteristics and with other special one: that to learn and grow by itself in knowledge and size.

  6. Growing pioneer plants for a lunar base

    Science.gov (United States)

    Kozyrovska, N. O.; Lutvynenko, T. L.; Korniichuk, O. S.; Kovalchuk, M. V.; Voznyuk, T. M.; Kononuchenko, O.; Zaetz, I.; Rogutskyy, I. S.; Mytrokhyn, O. V.; Mashkovska, S. P.; Foing, B. H.; Kordyum, V. A.

    A precursory scenario of cultivating the first plants in a lunar greenhouse was elaborated in frames of a conceptual study to grow plants for a permanently manned lunar base. A prototype plant growth system represents an ornamental plant Tagetes patula L. for growing in a lunar rock anorthosite as a substrate. Microbial community anticipated to be in use to support a growth and development of the plant in a substrate of low bioavailability and provide an acceptable growth and blossoming of T. patula under growth limiting conditions.

  7. California Hass Avocado: Profiling of Carotenoids, tocopherol, fatty acid, and fat content during maturation and from different growing areas

    Science.gov (United States)

    Lu, Qing-Yi; Zhang, Yanjun; Wang, Yue; Wang, David; Lee, Ru-po; Gao, Kun; Byrns, Russell; Heber, David

    2009-01-01

    The California Hass avocado (Persea Americana) is an example of a domesticated berry fruit that matures on the tree during its growing season but ripens only after being harvested. Avocados are typically harvested multiple times during the growing season in California. Previous research has demonstrated potential health benefits of avocados and extracts of avocado against inflammation and cancer cell growth, but seasonal variations in the phytochemical profile of the fruits being studied may affect the results obtained in future research. Therefore in the present study, avocados were harvested in January, April, July and September 2008 from four different growing locations in California (San Luis Obispo, Ventura, Riverside and San Diego), and analyzed fortotal fat content, fatty acid profile, carotenoids and vitamin E. A significant increase in total carotenoid and fat content of avocados from all regions was noted as the season progressed from January to September. Four carotenoids not previously described in the avocado were quantified. The total content of carotenoids was highly correlated with total fat content (r=0.99, pavocado.. Future clinical research on the health benefits of the avocado should specify the time of harvest, degree of ripening, growing area and the total phytochemical profile of the fruit or extract being studied. These steps will enable researchers to account for potential nutrient-nutrient interactions that might affect the research outcomes. PMID:19813713

  8. Genetics Home Reference: seasonal affective disorder

    Science.gov (United States)

    ... is genetic testing? How can I find a genetics professional in my area? Other Names for This Condition affective disorder, seasonal depression in a seasonal pattern depression; seasonal major depressive ...

  9. Growing up Female: As Six become One

    Science.gov (United States)

    Balto, Karen; Balto, Sylvia

    1971-01-01

    Growing up Female: As Six Become One" is an excellent film for people of any age and appropriate for any group. The film explores the lives of six American women showing how they are socialized and what their roles in society are. (Author)

  10. Growing Languages with Metamorphic Syntax Macros

    DEFF Research Database (Denmark)

    Brabrand, Claus; Schwartzbach, Michael Ignatieff

    2002-01-01

    simultaneously on multiple parse trees at once. The result is a highly flexible mechanism for growing new language constructs without resorting to compile-time programming. In fact, whole new languages can be defined at surprisingly low cost.This work is fully implemented as part of the bigwig system...

  11. Pueblo Girls: Growing Up in Two Worlds.

    Science.gov (United States)

    Keegan, Marcia

    This book portrays San Ildefonso Pueblo on the east bank of the Rio Grande river in New Mexico through the lives of Sonja, age 10, and her sister Desiree, age 8. Growing up in San Ildefonso Pueblo, the girls enjoy the same activities as other American girls, such as basketball, cheerleading, playing video games, and sending e-mail. But they also…

  12. What a Pain! Kids and Growing Pains

    Science.gov (United States)

    ... Steven Dowshen, MD Date reviewed: June 2015 For Teens For Kids For Parents MORE ON THIS TOPIC Why Do I Have Pain? How Do Pain Relievers Work? Growth Disorders I'm Growing Up - But Am I Normal? What Medicines Are and What They Do Feeling Too Tall or Too Short Contact Us Print Resources Send ...

  13. Growing Income Inequality Threatens American Education

    Science.gov (United States)

    Duncan, Greg J.; Murnane, Richard J.

    2014-01-01

    The first of two articles in consecutive months describes the origins and nature of growing income inequality, and some of its consequences for American children. It documents the increased family income inequality that's occurred over the past 40 years and shows that the increased income disparity has been more than matched by an expanding…

  14. Growing Up in Germany: A National Report.

    Science.gov (United States)

    Krappmann, Lothar

    1999-01-01

    Summarizes a Federal Ministry of Youth report on the conditions under which children grow up in Germany. Notes manifold problems that children face under today's living conditions. Presents recommendations and suggestions for providing a network of measures, relationships, and institutions to support children's development and education in family,…

  15. Determination of responses of growing pigs to

    African Journals Online (AJOL)

    1998-03-09

    Mar 9, 1998 ... The responses in growing pigs to balanced diets at different dietary energy levels are estimated from published data after recalculation of digestible energy (DE) iev- els using standard tables. Although responses in live weight gain (ADG), food intake (Fl), digestible energy intake (DEI) and food conversion ...

  16. How fast to northern hardwoods grow?

    Science.gov (United States)

    Rapheal Zon; H.F. Scholz

    1929-01-01

    The knowledge of the rate at which trees grow in virgin forests, after clear cutting and under selective logging, is indispensable in any forest calculations or forest practice. The enactment of the Forest Crop Law, which brought under its operation about 175,000 acres of cut-over land during the first year, the example set by several progressive lumbermen in selective...

  17. Growing Up in an Alcoholic Family.

    Science.gov (United States)

    Abbott, Stephanie

    1993-01-01

    Discusses problems faced by children growing up in an alcoholic family. Reviews four survivor roles of children of alcoholics (COAs): super-coper, scapegoat, lost child, and family mascot. Describes alcoholism as a disease of denial. Reviews the Children of Alcoholics movement begun by adult COAs to become advocates for COAs. (NB)

  18. Growing up as a Young Artist

    Science.gov (United States)

    Szekely, George

    2012-01-01

    "Growing Up as a Young Artist" is an illustrated book assignment that involves researching family scrapbooks, photo albums and films, and inquiring about family anecdotes for clues to one's artistic roots. Students creatively reflect on their early memories of imaginative events, as each page is filled with memories of creative activities they…

  19. Play Games to Grow up Bilingual

    DEFF Research Database (Denmark)

    Valente, Andrea; Marchetti, Emanuela

    2007-01-01

    A new kind of computer game is proposed, to support the linguistic development of primary school children, growing in multilingual environments: with it players will be able to simultaneously learn multiple languages. The novel idea is to treat words in different languages as physical items, that...

  20. Play Games to Grow up Bilingual

    DEFF Research Database (Denmark)

    Valente, Andrea; Marchetti, Emanuela

    2008-01-01

    A new kind of computer game is proposed, to support the linguistic development of primary school children, growing in multilingual environments: with it players will be able to simultaneously learn multiple languages. The novel idea is to treat words in different languages as physical items, that...

  1. Preliminary characterization of slow growing rhizobial strains ...

    African Journals Online (AJOL)

    In this paper, we did some preliminary characterization of six slow growing rhizobial strains, isolated from Retama monosperma (L.) Boiss. root nodules sampled from 3 sites along the coast of Oran (CapeFalcon, Bousfer and MersElHadjadj) in Northwestern Algeria. Results of this study showed that all strains had a very ...

  2. growing African giant rats Cricetomys gambianus

    African Journals Online (AJOL)

    Thermoregulation and evaporative water loss in growing African giant rats Cricetomys gambianus. M.H. Knight. Mammal Research Institute, University of Pretoria, Pretoria. With an increase in mass, weaned giant rat pups. Cricetomys gambianus, showed a corresponding decline in mass specific metabolism, conductance ...

  3. 2008 Swimming Season Fact Sheets

    Science.gov (United States)

    To help beachgoers make informed decisions about swimming at U.S. beaches, EPA annually publishes state-by-state data about beach closings and advisories for the previous year's swimming season. These fact sheets summarize that information by state.

  4. 2010 Swimming Season Fact Sheets

    Science.gov (United States)

    To help beachgoers make informed decisions about swimming at U.S. beaches, EPA annually publishes state-by-state data about beach closings and advisories for the previous year's swimming season. These fact sheets summarize that information by state.

  5. 2009 Swimming Season Fact Sheets

    Science.gov (United States)

    To help beachgoers make informed decisions about swimming at U.S. beaches, EPA annually publishes state-by-state data about beach closings and advisories for the previous year's swimming season. These fact sheets summarize that information by state.

  6. 2007 Swimming Season Fact Sheets

    Science.gov (United States)

    To help beachgoers make informed decisions about swimming at U.S. beaches, EPA annually publishes state-by-state data about beach closings and advisories for the previous year's swimming season. These fact sheets summarize that information by state.

  7. 2006 Swimming Season Fact Sheets

    Science.gov (United States)

    To help beachgoers make informed decisions about swimming at U.S. beaches, EPA annually publishes state-by-state data about beach closings and advisories for the previous year's swimming season. These fact sheets summarize that information by state.

  8. Human land-use change impacts rainfall seasonality

    Science.gov (United States)

    Wang-Erlandsson, Lan; van der Ent, Ruud; Fetzer, Ingo; Keys, Patrick; Savenije, Hubert; Gordon, Line

    2017-04-01

    Anthropogenic land-use change has profoundly changed the Earth's terrestrial water cycle. Studies of how land-use change induced modifications in terrestrial evaporation alters atmospheric moisture content and subsequent precipitation (i.e.., moisture recycling) have primarily focussed on the annual mean impacts. However, the functioning of agriculture and ecosystems are often dependent on the onset, length, and magnitude of the growing season rainfall. Hence, rainfall seasonality is of crucial importance. Here, we (1) analyse how humans have altered rainfall seasonality through land-use change induced modification of moisture recycling, (2) investigate the mechanisms for the rainfall seasonality changes, and (3) discuss how downwind regions may be affected by rainfall seasonality changes. We model human land-use change effects (including irrigation) on evaporation using the global hydrological model STEAM and trace precipitation changes using the atmospheric moisture tracking scheme WAM-2layers. We find that changes in rainfall seasonality is considerably stronger than changes to mean annual precipitation, and is accentuated in locations downwind to significant land-use changes. In particular, we associate sustained rainfall season downwind with land-use types that favour transpiration. This effect is explained by the long residence time of transpiration in both the unsaturated zone and the atmosphere, in contrast to interception and soil evaporation. Our results shed light on the human influence of hydrological systems both locally and at large distances, and which may have crucial implications for agricultural production and ecosystem functioning. These insights are important in a time of both rapid land-use and climate change.

  9. CARROT SEED GROWING THROUGH WINTERING SEEDLINGS

    Directory of Open Access Journals (Sweden)

    A. P. Zvedenuk

    2017-01-01

    Full Text Available The results of research work on carrot seed growing through wintering seedlings carried out at laboratory of seed studies and seed production of Transnistrian Research Institute of Agriculture, on the soil of the first terrace at the rive Dniester were presented in the article. Seed bearing plants of garden carrot ‘Krasavka’ were the object of the study. The seeds were sown to produce the seedlings on 15-16 August. In the first decade of December the plants were covered with white agrotextile with density 23g/m2 that was removed at the beginning of April. The proportion of plant that passed the winter depending on a year of cultivation was 95-100% under argotextile, and 50-80% in open plot. The plants under agrotextile reached 28 cm a high and had 5-7 well-developed leaves, while those on the open plot were at phase of active foliage growing about 10-13 cm. long. Thus, for early mechanized planting in optimal terms the wintering seedlings grown under agrotextile had the best biometrical characteristics. Moreover the outcome of carrot seedlings was 1.2-1.25 million per hectare. Such quantity of seedlings was sufficient to plant 9-10 ha of carrot plants, where the coefficient of multiplication reached 9-10, and only 3 when growing seeds through mother plant as biennial culture. Viability of seed plants grown through seedlings was 100%. Losses of plant with weight 120-150 grams from damage caused by diseases was 23%. The seed yield, when growing seedlings was 639 kg/ha, but growing through plants was 332 kg/ha. The seed outcome suitable for precise mechanized sowing through seedling growing was 77%, where seed germination was 90%, with seed fraction 1.51 and >2.0 mm. It was essentially improved their yielding characteristics. Seed outcome from this fraction obtained through planting method was 32%. The proportion of seeds in fraction 1-1.5 mm was 68%. For mechanized single-seed sowing, the seeds can be used only after mini-coating. The seed

  10. GEOS-5 seasonal forecast system

    Science.gov (United States)

    Borovikov, Anna; Cullather, Richard; Kovach, Robin; Marshak, Jelena; Vernieres, Guillaume; Vikhliaev, Yury; Zhao, Bin; Li, Zhao

    2017-09-01

    Ensembles of numerical forecasts based on perturbed initial conditions have long been used to improve estimates of both weather and climate forecasts. The Goddard Earth Observing System (GEOS) Atmosphere-Ocean General Circulation Model, Version 5 (GEOS-5 AOGCM) Seasonal-to-Interannual Forecast System has been used routinely by the GMAO since 2008, the current version since 2012. A coupled reanalysis starting in 1980 provides the initial conditions for the 9-month experimental forecasts. Once a month, sea surface temperature from a suite of 11 ensemble forecasts is contributed to the North American Multi-Model Ensemble (NMME) consensus project, which compares and distributes seasonal forecasts of ENSO events. Since June 2013, GEOS-5 forecasts of the Arctic sea-ice distribution were provided to the Sea-Ice Outlook project. The seasonal forecast output data includes surface fields, atmospheric and ocean fields, as well as sea ice thickness and area, and soil moisture variables. The current paper aims to document the characteristics of the GEOS-5 seasonal forecast system and to highlight forecast biases and skills of selected variables (sea surface temperature, air temperature at 2 m, precipitation and sea ice extent) to be used as a benchmark for the future GMAO seasonal forecast systems and to facilitate comparison with other global seasonal forecast systems.

  11. Differentiated seasonal vegetation cover dynamics of degraded grasslands in Inner Mongolia recorded by continuous photography technique

    Science.gov (United States)

    Xu, Xiaotian; Liu, Hongyan; Liu, Xu; Song, Zhaoliang; Wang, Wei; Qiu, Shuang

    2017-05-01

    Influence of climate change on the grassland phenology has attracted more and more attentions of ecologists. Although dozens of studies have been conducted, there have been few records examining the phenology differences of grasslands with different plant species compositions. Using continuous photography and image processing methods, this study examined seasonal vegetation cover dynamics of grasslands along a degradation gradient to clarify the influence of vegetation composition on the dynamics of vegetation cover during growing season. Our results revealed that phenological patterns of grasslands differentiated with their degradation status. Abandoned farmland (AF) and severely degraded grassland (SD) with most annuals and least climax species had the earliest start of growing season, while AF and extremely degraded grassland (ED) dominated by grasses had the earliest end of growing season. The start and end of growing season were strongly related to the relative cover of climax species and grasses. The results presented in this study support the possibility of using digital photography to capture the role of plant species composition on vegetation phenology in grasslands.

  12. Ecohydrological and Biophysical Controls on Carbon Cycling in Two Seasonally Snow-covered Forests

    Science.gov (United States)

    Chan, A. M.; Brooks, P. D.; Burns, S. P.; Litvak, M. E.; Blanken, P.; Bowling, D. R.

    2014-12-01

    In many seasonally snow-covered forests, the snowpack is the primary water resource. The snowpack also serves as an insulating layer over the soil, warming soil throughout the winter and preserving moisture conditions from the preceding fall. Therefore, the total amount of water in the snowpack as well as the timing and duration of the snow-covered season are likely to have a strong influence on forest productivity through the regulation of the biophysical environment. We investigated how interannual variation in the amount and timing of seasonal snow cover affect winter carbon efflux and growing season carbon uptake at the Niwot Ridge AmeriFlux site (NWT) in Colorado (3050m a.s.l.; 40˚N) and the Valles Caldera Mixed-Conifer AmeriFlux site (VC) in New Mexico (3003m a.s.l.; 36˚N). The tree species composition at NWT is dominated by Abies lasiocarpa, Picea engelmannii, and Pinus contorta. At VC, the dominant tree species are Pseudotsuga menziesii, Abies concolor, Picea pungens, Pinus strobiformis, Pinus flexilis, Pinus ponderosa, and Populus tremuloides. We used net ecosystem exchange (NEE) and climate data from 1999-2012 at NWT and 2007-2012 at VC to divide each year into the growing season, when NEE is negative, and the winter, when NEE is positive. Snow water equivalent (SWE), precipitation, and duration of snow cover data were obtained from USDA/NRCS SNOTEL sites near each forest. At both sites, the start of the growing season was strongly controlled by air temperature, but growing season NEE was not dependent on the length of the growing season. At NWT, total winter carbon efflux was strongly influenced by both the amount and duration of the snowpack, measured as SWE integrated over time. Years with higher integrated SWE had higher winter carbon efflux and also had warmer soil under the snowpack. These patterns were not seen at VC. However, peak SWE amount was positively correlated with growing season NEE at VC, but not at NWT. These results suggest that

  13. Potential of remotely-sensed data for mapping sediment connectivity pathways and their seasonal changes in dryland environments

    Science.gov (United States)

    Foerster, Saskia; Wilczok, Charlotte; Brosinsky, Arlena; Kroll, Anja; Segl, Karl; Francke, Till

    2014-05-01

    pathways have been mapped for two adjacent sub-catchments (approx. 70 km²) of the Isábena River in different seasons using a quantitative connectivity index based on fractional vegetation cover and topography data. Fractional cover of green and dry vegetation, bare soil and rock were derived by applying a Multiple Endmember Spectral Mixture Analysis approach applied to a hyperspectral image dataset. Sediment connectivity was mapped using the Index of Connectivity (Borselli et al. 2008), in which the effect of land cover on runoff and sediment fluxes is expressed by a spatially distributed weighing factor (in this study, the cover and management factor of the RUSLE). The resulting connectivity maps show that areas behave very differently with regard to connectivity, depending on the land cover but also on the spatial distribution of vegetation abundances and topographic barriers. Most parts of the catchment show higher connectivity values in summer than in spring. The studied sub-catchments show a slightly different connectivity behaviour reflecting the different land cover proportions and their spatial configuration. Future work includes the incorporation of sediment connectivity information into a hydrological model (WASA-SED, Mueller et al. 2010) to better reflect connectivity processes and testing the sensitivity of the model to different input data.

  14. The 2016 North Atlantic hurricane season: A season of extremes

    Science.gov (United States)

    Collins, Jennifer M.; Roache, David R.

    2017-05-01

    The 2016 North Atlantic hurricane season had an early start with a rare and powerful storm for January impacting the Azores at hurricane force. Likewise, the end of season heralded Otto which was record breaking in location and intensity being a high-end Category 2 storm at landfall over southern central America in late November. We show that high precipitable water, positive relative vorticity, and low sea level pressure allowed for conducive conditions. During the season, few storms occurred in the main development region. While some environmental conditions were conducive for formation there (such as precipitable water, relative vorticity, and shear), the midlevel relative humidity was too low there for most of the season, presenting very dry conditions in that level of the atmosphere. We further find that the October peak in the accumulated cyclone energy was related to environmentally conducive conditions with positive relative humidity, precipitable water, relative humidity, and low values of sea level pressure. Overall 2016 was notable for a series of extremes, some rarely, and a few never before observed in the Atlantic basin, a potential harbinger of seasons to come in the face of ongoing global climate change.

  15. Learning Topologies with the Growing Neural Forest.

    Science.gov (United States)

    Palomo, Esteban José; López-Rubio, Ezequiel

    2016-06-01

    In this work, a novel self-organizing model called growing neural forest (GNF) is presented. It is based on the growing neural gas (GNG), which learns a general graph with no special provisions for datasets with separated clusters. On the contrary, the proposed GNF learns a set of trees so that each tree represents a connected cluster of data. High dimensional datasets often contain large empty regions among clusters, so this proposal is better suited to them than other self-organizing models because it represents these separated clusters as connected components made of neurons. Experimental results are reported which show the self-organization capabilities of the model. Moreover, its suitability for unsupervised clustering and foreground detection applications is demonstrated. In particular, the GNF is shown to correctly discover the connected component structure of some datasets. Moreover, it outperforms some well-known foreground detectors both in quantitative and qualitative terms.

  16. Efficient Communication Management in a Growing Organisation

    OpenAIRE

    Alakotila, Susanna

    2017-01-01

    The purpose of this thesis is to analyse the importance of organisational communication and to explain how communication should be managed for it to be effective. Two fast-growing companies were interviewed for the thesis, who give entail on how they have managed communication regarding the organisational changes. Organisational communication is divided into external, stakeholder and internal communication in this study. With the help of interviews from two case companies, researcher offers r...

  17. Transformational Leadership Which Can Grow Organizational Commitment

    OpenAIRE

    Silalahi, Betty Yuliani

    2008-01-01

    A meta-analysis consist of 45 studies from 20 articles and 20860 subjects evaluated the correlation between Transformational leadership and Organizational commitment. Summary analysis provided support for the hypothesis that transformational leadership has a correlation on organizational commitment. The purpose of the study is to analyzed the data from the primer study and to support the hypothesis or refuse from the studies. Result indicated that transformational leadership can grow organiza...

  18. Shape of the growing front of biofilms

    Science.gov (United States)

    Wang, Xin; Stone, Howard A.; Golestanian, Ramin

    2017-12-01

    The spatial organization of bacteria in dense biofilms is key to their collective behaviour, and understanding it will be important for medical and technological applications. Here we study the morphology of a compact biofilm that undergoes unidirectional growth, and determine the condition for the stability of the growing interface as a function of the nutrient concentration and mechanical tension. Our study suggests that transient behaviour may play an important role in shaping the structure of a biofilm.

  19. Economic Gardening and the Grow Kentucky Program

    OpenAIRE

    Robbins, Lynn W.; Allen, James E. IV

    2015-01-01

    In 2014, the Community and Economic Development Initiative of Kentucky (CEDIK) and the Kentucky Small Business Development Center (KSBDC), launched Grow Kentucky, Kentucky’s only certified Economic Gardening program. The program helps second-stage entrepreneurial growth companies penetrate existing markets, identify new markets, monitor competitors, track industry trends, locate customer clusters, use search engine optimization/social media for marketing and various other customized research....

  20. Growing Role of Retail in Distribution Channels

    OpenAIRE

    Ishak Mesic

    2011-01-01

    This article aims to demonstrate the growing role of retail trade (retail) in the channels of distribution of goods both in domestic and international markets. Technical-technological development has provided great opportunities for all production of material goods, so that the focus of problem in the economic possibilities of playing shifted from production to sales opportunities, or consumption. The ultimate consumers and their needs and requirements have become a central area of study, bas...

  1. GRoW Buffalo Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Bohm, Martha [Univ. at Buffalo, NY (United States)

    2016-04-17

    This document provides final reporting on the GRoW Home, University at Buffalo's entry to the 2015 Solar Decathlon competition in Irvine, CA. The report summarizes fundraising efforts, documents media outreach, lists online presence, analyzes the organizer's communication, describes post-competition life of the house and future employment plans for student team members. Last, it suggests improvements for future decathlons.

  2. The sensitivity of wood production to seasonal and interannual variations in climate in a lowland Amazonian rainforest.

    Science.gov (United States)

    Rowland, Lucy; Malhi, Y; Silva-Espejo, J E; Farfán-Amézquita, F; Halladay, K; Doughty, C E; Meir, P; Phillips, O L

    2014-01-01

    Understanding climatic controls on tropical forest productivity is key to developing more reliable models for predicting how tropical biomes may respond to climate change. Currently there is no consensus on which factors control seasonal changes in tropical forest tree growth. This study reports the first comprehensive plot-level description of the seasonality of growth in a Peruvian tropical forest. We test whether seasonal and interannual variations in climate are correlated with changes in biomass increment, and whether such relationships differ among trees with different functional traits. We found that biomass increments, measured every 3 months on the two plots, were reduced by between 40 and 55% in the peak dry season (July-September) relative to peak wet season (January-March). The seasonal patterns of biomass accumulation are significantly (p < 0.01) associated with seasonal patterns of rainfall and soil water content; however, this may reflect a synchrony of seasonal cycles rather than direct physiological controls on tree growth rates. The strength of the growth seasonality response among trees is significantly correlated to functional traits: consistent with a hypothesised trade-off between maximum potential growth rate and hydraulic safety, tall and fast-growing trees with broad stems had the most strongly seasonal biomass accumulation, suggesting that they are more productive in the wet season, but more vulnerable to water limitation in the dry season.

  3. Biomass accumulation in rapidly growing loblolly pine and sweetgum

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Thomas M.; Gresham, Charles A. [Baruch Institute of Coastal Ecology and Forest Science, Clemson University, P.O. Box 596, Georgetown, SC 29442 (United States)

    2006-04-15

    Loblolly pine (Pinus taeda) and sweetgum (Liquidambar styraciflua) trees, growing in International Paper Company's study of intensive management on marginal agricultural land near Bainbridge GA, were destructively sampled at the end of the sixth growing season. All trees were single family blocks of genetically superior trees planted 2.5m apart on sub-soiled rows 3.6m apart and grown with complete competition control. Management treatments were: control, irrigation, irrigation plus fertilization, and irrigation plus fertilization plus pest control. Tree measures were basal diameter, DBH, height of live crown, diameter at base of live crown, and total height. Twenty trees of each species were destructively sampled. Stems were sectioned at 1m intervals, stem diameter determined at each end and sections were weighed green. Branches were removed and height, basal diameter, and length were measured on each branch. Branches were separated into foliated and unfoliated segments and weighed green. A stem disk and branch from each meter were returned to the lab to determine dry weight: green weight ratio. Foliated limb: foliage ratios were also determined from sub-sampled branches. Intensive culture resulted in larger growth differences for sweetgum (most intensive treatment 9.5m tall, 13.1cm DBH; control trees 5.0m tall, 6.3cm DBH) than in pine (most intensive treatment 10.3m tall, 17.7cm DBH; control, 7.6m tall, 13.4cm DBH). The pipe model of tree development explained dimensions of the upper 5m of crown with leaf biomass highly correlated to branch basal area (r{sup 2} from 0.697 to 0.947). There was a constant ratio of leaf biomass to branch basal area (50gm/cm{sup 2} for pine, 30gm/cm{sup 2} for sweetgum). We also found a constant ratio of bole basal area to cumulative branch basal area throughout the crowns. Rapidly growing pines produced about 49Mgha{sup -1} of stem biomass, 11Mgha{sup -1} of dead branch biomass, and 17Mgha{sup -1} of unfoliated branch biomass at

  4. Seasonal variation in sports participation.

    Science.gov (United States)

    Schüttoff, Ute; Pawlowski, Tim

    2018-02-01

    This study explores indicators describing socio-demographics, sports participation characteristics and motives which are associated with variation in sports participation across seasons. Data were drawn from the German Socio-Economic Panel which contains detailed information on the sports behaviour of adults in Germany. Overall, two different measures of seasonal variation are developed and used as dependent variables in our regression models. The first variable measures the coefficient of (seasonal) variation in sport-related energy expenditure per week. The second variable measures whether activity drops below the threshold as defined by the World Health Organization (WHO). Results suggest that the organisational setting, the intensity and number of sports practised, and the motive for participation are strongly correlated with the variation measures used. For example, both, participation in a sports club and a commercial facility, are associated with reduced seasonal variation and a significantly higher probability of participating at a volume above the WHO threshold across all seasons. These findings give some impetus for policymaking and the planning of sports programmes as well as future research directions.

  5. Carbon dioxide and methane fluxes: Seasonal dynamics from inland riparian ecosystems, northeast China

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Qiao-Qi [School of Nature Conservation, Beijing Forestry University, 35 Tsinghua-east Road, Haidian District, Beijing 100083 (China); Shi, Kun, E-mail: kunshi11@yahoo.com.cn [School of Nature Conservation, Beijing Forestry University, 35 Tsinghua-east Road, Haidian District, Beijing 100083 (China); Damerell, Peter; Whitham, Charlotte [School of Nature Conservation, Beijing Forestry University, 35 Tsinghua-east Road, Haidian District, Beijing 100083 (China); Yu, Guo-Hai; Zou, Chang-Lin [Momoge National Nature Reserve, Zhenlai, Baicheng 137316 (China)

    2013-11-01

    Riparian wetland ecosystems have been described as significant hotspots for carbon dioxide (CO{sub 2}) and methane (CH{sub 4}) fluxes, but their role in the release and sequestration of these greenhouse gases has been insufficiently assessed within China. The influences of vegetation and soil parameters on daily and seasonal variations in carbon flux in the Nenjiang basin, northeast China, were recorded using a static closed-chamber technique during the non-growing (November and January) and growing (June, July and August) seasons of 2009–2010. Seasonal differences in average CO{sub 2} flux were observed (growing season: 6.605 g·C·m{sup −2} h{sup −1}; non-growing season: − 0.185 g·C·m{sup −2} h{sup −1}) and these were significantly correlated with CH{sub 4} emission (r = 0.532, p = 0.011) and soil temperature at 5 cm depth below ground (r = 0.852, p = 0.000). Average diel gaseous flux showed significant variation between hours for both gases (CO{sub 2} flux one-way ANOVA F = 3.075, p < 0.01; CH{sub 4} flux one way ANOVA F = 2.622, p < 0.05). Various significant correlations were also found between CH{sub 4} and CO{sub 2} fluxes and multiple vegetation and soil parameters. For example at both sites, growing season-CH{sub 4} flux was correlated with vegetation cover (r = 0.580, p < 0.05) and total vegetation phosphorous (r = 0.474, p < 0.05). This study allowed key temporal differences in gas release and their potential biotic and abiotic drivers to be identified. Crucially, it also highlighted important areas in need of further research, to enhance our understanding of gaseous flux from inland riparian habitats. - Highlights: ► Daily and seasonal variations in carbon fluxes were recorded from inland riparian habitats. ► The influences of vegetation and soil parameters on carbon flux exchanges were qualified. ► Seasonal differences in average CO{sub 2} was significantly correlated with CH{sub 4} emission and soil temperature. ► Growing season

  6. Seasonal phenology and species composition of the aphid fauna in a northern crop production area.

    Directory of Open Access Journals (Sweden)

    Sascha M Kirchner

    Full Text Available BACKGROUND: The species diversity of aphids and seasonal timing of their flight activity can have significant impacts on crop production, as aphid species differ in their ability to transmit plant viruses and flight timing affects virus epidemiology. The aim of the study was to characterise the species composition and phenology of aphid fauna in Finland in one of the northernmost intensive crop production areas of the world (latitude 64°. METHODOLOGY/PRINCIPAL FINDINGS: Flight activity was monitored in four growing seasons (2007-010 using yellow pan traps (YPTs placed in 4-8 seed potato fields and a Rothamsted suction trap. A total of 58,528 winged aphids were obtained, identified to 83 taxa based on morphology, and 34 species were additionally characterised by DNA barcoding. Seasonal flight activity patterns analysed based on YPT catch fell into three main phenology clusters. Monoecious taxa showed early or middle-season flight activity and belonged to species living on shrubs/trees or herbaceous plants, respectively. Heteroecious taxa occurred over the entire potato growing season (ca. 90 days. Abundance of aphids followed a clear 3-year cycle based on suction trap data covering a decade. Rhopalosiphum padi occurring at the end of the potato growing season was the most abundant species. The flight activity of Aphis fabae, the main vector of Potato virus Y in the region, and Aphis gossypii peaked in the beginning of potato growing season. CONCLUSIONS/SIGNIFICANCE: Detailed information was obtained on phenology of a large number aphid species, of which many are agriculturally important pests acting as vectors of plant viruses. Aphis gossypii is known as a pest in greenhouses, but our study shows that it occurs also in the field, even far in the north. The novel information on aphid phenology and ecology has wide implications for prospective pest management, particularly in light of climate change.

  7. A Malthusian Model for all Seasons

    DEFF Research Database (Denmark)

    Sharp, Paul Richard; Weisdorf, Jacob Louis

    associated with labour shortages (the high-season bottleneck on production), although there might be labour surplus during the low season. We introduce the concept of seasonality into a stylized Malthusian model, and endogenize the extent of agricultural labour input, which is then used to calculate labour...... surplus and the rate of labour productivity. We observe the effects of season-specific technological progress, and find that technological progress in the low-season increases labour surplus and labour productivity whilst, perhaps surprisingly, technological progress in the high-season, by relaxing...... the high-season bottleneck, leads to work intensification and a drop in labour surplus and labour productivity...

  8. Seasonality processes in deciduous fruit plants

    Energy Technology Data Exchange (ETDEWEB)

    Carini, F.; Fortunati, P.; Brambilla, M. [Universita Cattolica del Sacro Cuore, Faculty of Agricultural Sciences, Institute of Agricultural and Environmental Chemistry, Piacenza (Italy)

    2004-07-01

    The understanding of the processes that affect the behaviour of radionuclides in crops can both improve the assessment of the risk to man from ingestion of contaminated food and support policy makers to take actions in order to protect environment and to safeguard human health. Even if in the last years various studies have been carried out on fruits, this field is still affected by large uncertainty, due to the lack of knowledge and poor understanding of processes. Among the factors that affect the fruit contamination at harvest, seasonality, i.e. the time of the year when the deposition occurs, has not been object of proper attention. In the present paper the processes at short term of {sup 134}Cs and {sup 85}Sr in fruit plants, following deposition at different growing stages, have been studied. More in particular, results from a three-annual research on fruit plants - strawberry and blackberry - contaminated via leaves or via soil are used to discuss the relative contribution of the different processes - interception, absorption, translocation, remobilization, loss - to seasonality. The process of leaf-to-fruit translocation is controlled by the metabolic activity of the plant. The highest contamination for the elements mobile in the phloem occurs when the process of translocation prevails, while that for the non mobile elements occurs when the process of direct deposition prevails. The residual activity in the plant depends on the stage of plant growth. At anthesis it is lower for {sup 134}Cs than for {sup 85}Sr, but not during ripening and pre-dormancy. The removal of radioactivity from leaves is lower during dormancy than in Spring or Summer, but a large percentage of radioactivity is lost with the dead leaves at the end of Winter. (author)

  9. Seasonal response of biomass growth and allocation of a boreal bioenergy crop (Phalaris arundinacea L.) to climate change

    Energy Technology Data Exchange (ETDEWEB)

    Chang Zhang

    2013-06-01

    The aim of this work was to analyse how the seasonal biomass growth and allocation in a boreal bioenergy crop (Phalaris arundinacea L., hereafter RCG) were affected by elevated temperature and CO{sub 2} under different levels of groundwater. For this purpose, plants in peat monoliths representing young and old cultivations were grown in auto-controlled environmental chambers over two growing seasons (April-September, 2009 and 2010) under elevated temperature (ambient + 3.5 deg C) and CO{sub 2} (700 {mu}mol mol{sup -1}). (CON: ambient conditions, EC: elevated CO{sub 2}, ET: elevated temperature, ETC: elevated temperature and CO{sub 2}). Three levels of groundwater, ranging from high (HW, 0 cm below the soil surface), to normal (NW, 20 cm below the soil surface) and low (LW, 40 cm below the soil surface), were used. Compared to growth under CON, ET enhanced leaf development and photosynthesis in the RCG plant. Consequently, ET enhanced biomass growth during early growing periods. It also reduced photosynthesis and caused earlier leaf senescence during later growing periods. ET therefore reduced total biomass growth across the entire growing season. EC significantly increased biomass growth throughout the growing period primarily because of increased leaf area and photosynthesis. LW decreased the growth of RCG, mainly because of lower leaf area and photosynthesis. Furthermore, LW accelerated the cessation of growth, thus making the growing season shorter compared with the effects of higher groundwater levels. The LW- induced reductions in biomass growth were exacerbated by ET and partially mitigated by EC. The ETC slightly increased final plant growth. The age of cultivation did not affect the biomass growth among the three major organs (leaf, stem and root) and thus did not affect total biomass growth. Biomass growth was mainly allocated to leaves (LMF) and stems (SMF) in the early growing season, to stems in the middle of the growing season and to roots (RMF) later

  10. Growing media constituents determine the microbial nitrogen conversions in organic growing media for horticulture.

    Science.gov (United States)

    Grunert, Oliver; Reheul, Dirk; Van Labeke, Marie-Christine; Perneel, Maaike; Hernandez-Sanabria, Emma; Vlaeminck, Siegfried E; Boon, Nico

    2016-05-01

    Vegetables and fruits are an important part of a healthy food diet, however, the eco-sustainability of the production of these can still be significantly improved. European farmers and consumers spend an estimated €15.5 billion per year on inorganic fertilizers and the production of N-fertilizers results in a high carbon footprint. We investigated if fertilizer type and medium constituents determine microbial nitrogen conversions in organic growing media and can be used as a next step towards a more sustainable horticulture. We demonstrated that growing media constituents showed differences in urea hydrolysis, ammonia and nitrite oxidation and in carbon dioxide respiration rate. Interestingly, mixing of the growing media constituents resulted in a stimulation of the function of the microorganisms. The use of organic fertilizer resulted in an increase in amoA gene copy number by factor 100 compared to inorganic fertilizers. Our results support our hypothesis that the activity of the functional microbial community with respect to nitrogen turnover in an organic growing medium can be improved by selecting and mixing the appropriate growing media components with each other. These findings contribute to the understanding of the functional microbial community in growing media and its potential role towards a more responsible horticulture. © 2016 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  11. Within-season variation in sexual selection in a fish with dynamic sex roles.

    Science.gov (United States)

    Wacker, Sebastian; Amundsen, Trond; Forsgren, Elisabet; Mobley, Kenyon B

    2014-07-01

    The strength of sexual selection may vary between species, among populations and within populations over time. While there is growing evidence that sexual selection may vary between years, less is known about variation in sexual selection within a season. Here, we investigate within-season variation in sexual selection in male two-spotted gobies (Gobiusculus flavescens). This marine fish experiences a seasonal change in the operational sex ratio from male- to female-biased, resulting in a dramatic decrease in male mating competition over the breeding season. We therefore expected stronger sexual selection on males early in the season. We sampled nests and nest-holding males early and late in the breeding season and used microsatellite markers to determine male mating and reproductive success. We first analysed sexual selection associated with the acquisition of nests by comparing nest-holding males to population samples. Among nest-holders, we calculated the potential strength of sexual selection and selection on phenotypic traits. We found remarkable within-season variation in sexual selection. Selection on male body size related to nest acquisition changed from positive to negative over the season. The opportunity for sexual selection among nest-holders was significantly greater early in the season rather than late in the season, partly due to more unmated males. Overall, our study documents a within-season change in sexual selection that corresponds with a predictable change in the operational sex ratio. We suggest that many species may experience within-season changes in sexual selection and that such dynamics are important for understanding how sexual selection operates in the wild. © 2014 John Wiley & Sons Ltd.

  12. Nurturing a growing field: Computers & Geosciences

    Science.gov (United States)

    Mariethoz, Gregoire; Pebesma, Edzer

    2017-10-01

    Computational issues are becoming increasingly critical for virtually all fields of geoscience. This includes the development of improved algorithms and models, strategies for implementing high-performance computing, or the management and visualization of the large datasets provided by an ever-growing number of environmental sensors. Such issues are central to scientific fields as diverse as geological modeling, Earth observation, geophysics or climatology, to name just a few. Related computational advances, across a range of geoscience disciplines, are the core focus of Computers & Geosciences, which is thus a truly multidisciplinary journal.

  13. Parallelized seeded region growing using CUDA.

    Science.gov (United States)

    Park, Seongjin; Lee, Jeongjin; Lee, Hyunna; Shin, Juneseuk; Seo, Jinwook; Lee, Kyoung Ho; Shin, Yeong-Gil; Kim, Bohyoung

    2014-01-01

    This paper presents a novel method for parallelizing the seeded region growing (SRG) algorithm using Compute Unified Device Architecture (CUDA) technology, with intention to overcome the theoretical weakness of SRG algorithm of its computation time being directly proportional to the size of a segmented region. The segmentation performance of the proposed CUDA-based SRG is compared with SRG implementations on single-core CPUs, quad-core CPUs, and shader language programming, using synthetic datasets and 20 body CT scans. Based on the experimental results, the CUDA-based SRG outperforms the other three implementations, advocating that it can substantially assist the segmentation during massive CT screening tests.

  14. Growing Quality in Qualitative Health Research

    Directory of Open Access Journals (Sweden)

    Mary Ellen Macdonald PhD

    2009-06-01

    Full Text Available Qualitative methodologies are growing in popularity in health research; however, the integration of these methodologies into the clinical context is not always straightforward. In this article the author discusses some of the paradigmatic and methodological tensions that characterize the use of qualitative methodologies in clinical health research and showcase one solution to these tensions. The McGill Qualitative Health Research Group is a scholarly group of qualitative health researchers working together to advance a qualitative research agenda in clinical disciplines.

  15. Mapping Nutrients Crucial to a Growing Population

    Science.gov (United States)

    Tarnowski, J. R.; Cassidy, E. S.; Gerber, J. S.

    2011-12-01

    Over two billion people worldwide suffer from inadequate levels of micronutrients, mainly in the form of iodine, iron, and vitamin A deficiencies. With a growing population, producing crops that contain high amounts of these micronutrients is of increased importance. Addressing these deficiencies sustainably requires a detailed examination of the agricultural production of the micronutrients. The purpose of this study is to determine whether or not enough of these important nutrients are produced to meet the nutritional needs of the global population, and to determine where nutrients are most deficient. We used area specific crop production data to map where and how much iron and vitamin A are produced from major crops.

  16. Growing in darkness: The etiolated lupin hypocotyls

    OpenAIRE

    Sánchez-Bravo, José; Oliveros-Valenzuela, M Rocío; Nicolás, Carlos; Acosta, Manuel

    2008-01-01

    Epigeal germination of a dicot, like lupin (Lupinus albus L.), produces a seedling with a characteristic hypocotyl, which grows in darkness showing a steep growth gradient with an elongation zone just below the apex. The role of phytohormones, such as auxin and ethylene, in etiolated hypocotyl growth has been the object of our research for some time. The recent cloning and expression of three genes of influx and efflux carriers for polar auxin transport (LaAUX1, LaPIN1 and LaPIN3) reinforces ...

  17. The U2U Corn Growing Degree Day tool: Tracking corn growth across the US Corn Belt

    Directory of Open Access Journals (Sweden)

    James R. Angel

    2017-01-01

    Full Text Available The Corn Growing Degree Day (Corn GDD tool is a web-based product that can provide decision support on a variety of issues throughout the entire growing season by integrating current conditions, historical climate data, and projections of Corn GDD through the end of the growing season based on both National Weather Service computer model forecasts and climatology. The Corn GDD tool can help agricultural producers make a variety of important decisions before and during the growing season. This support can include: assessing the risk of early and late frosts and freezes that can cause crop damage; comparing corn hybrid maturity requirements and Corn GDD projections to select seed varieties and plan activities such as spraying; guiding marketing decisions based on historical and projected Corn GDDs when considering forward crop pricing (i.e., futures market. The Corn GDD tool provides decision support for corn producers in the central U.S. corn-producing states. Survey results, web statistics, and user feedback indicate that this tool is being actively used by decision makers.

  18. The influence of seasonal rainfall upon Sahel vegetation

    DEFF Research Database (Denmark)

    Proud, Simon Richard; Rasmussen, Laura Vang

    2011-01-01

    Throughout the Sahelian region of Africa, vegetation growth displays substantial inter-annual variation, causing widespread concern in the region as rain-fed agriculture and pastoralism are a means of sustenance for the predominantly rural population. Previously proposed factors behind variations...... include changes in total yearly rainfall, land-use change and migration. But these factors are not fully explanatory. This study addresses other possible factors for variation in vegetation patterns through the analysis of the Normalized Difference Vegetation Index (NDVI) produced by satellite sensors. We...... that if the start of the growing season, or the period in which the peak growth of vegetation occurs, is especially dry then plant growth may be stunted throughout the remainder of the season. These results enable better understanding of climate dynamics in the Sahel and allow more accurate forecasting of crop...

  19. Biofilm-growing intestinal anaerobic bacteria.

    Science.gov (United States)

    Donelli, Gianfranco; Vuotto, Claudia; Cardines, Rita; Mastrantonio, Paola

    2012-07-01

    Sessile growth of anaerobic bacteria from the human intestinal tract has been poorly investigated, so far. We recently reported data on the close association existing between biliary stent clogging and polymicrobial biofilm development in its lumen. By exploiting the explanted stents as a rich source of anaerobic bacterial strains belonging to the genera Bacteroides, Clostridium, Fusobacterium, Finegoldia, Prevotella, and Veillonella, the present study focused on their ability to adhere, to grow in sessile mode and to form in vitro mono- or dual-species biofilms. Experiments on dual-species biofilm formation were planned on the basis of the anaerobic strains isolated from each clogged biliary stent, by selecting those in which a couple of anaerobic strains belonging to different species contributed to the polymicrobial biofilm development. Then, strains were investigated by field emission scanning electron microscopy and confocal laser scanning microscopy to reveal if they are able to grow as mono- and/or dual-species biofilms. As far as we know, this is the first report on the ability to adhere and form mono/dual-species biofilms exhibited by strains belonging to the species Bacteroides oralis, Clostridium difficile, Clostridium baratii, Clostridium fallax, Clostridium bifermentans, Finegoldia magna, and Fusobacterium necrophorum. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  20. Tracheotomy in growing rats: histological aspects

    Directory of Open Access Journals (Sweden)

    Manna Mônica Cecília Bochetti

    2003-01-01

    Full Text Available PURPOSE: To compare morphologically three different types of tracheotomy in growing rats, applying microsurgical technique. METHODS: EPM-1 Wistar growing rats (n=57 weighing 88gm and aged 35 days were randomized in four groups, according tracheotomy incision type (longitudinal, transverse and tracheal segment excision, and sham group. Following intramuscular anesthesia with ketamine and xylazine, the trachea was exposed and incised, according to the group, and a hand-made endotracheal cannula was inserted into the organ, under sterile conditions. This cannula was removed after 7 days, and animals have been sacrificed 30 days later. Tracheas samples were submitted to histological study, stained by hematoxylin-eosin and Masson trichrome, evaluating fibrosis, inflammatory infiltrate and epidermoid metaplasia. RESULTS: There was more frequency of inflammatory infiltrate at the tracheal epithelium in the tracheal segment excision group (87% compared to the longitudinal (40% and transverse (36% incision groups (p=0.009. Evaluating epidermoid metaplasia, tracheal segment excision and the longitudinal groups presented 33% and 40%, respectively, compared to 0% of the transverse group (p=0.03. Concerning to fibrosis, in a global comparison (p=0.1 among the three groups there was no difference, however, compared to the longitudinal group the transverse group showed lower level of fibrosis (p=0.04. Sham group did not present any relevant morphologic alterations and it was used as reference pattern. CONCLUSION: Taken together, our data show that tracheal segment excision promotes more epithelium aggression and transverse tracheal incision shows less morphologic alterations.

  1. Immunotoxicity of ochratoxin A to growing gilts.

    Science.gov (United States)

    Harvey, R B; Elissalde, M H; Kubena, L F; Weaver, E A; Corrier, D E; Clement, B A

    1992-10-01

    Ochratoxin A (OA) was incorporated in the diets of growing gilts (mean body weight, 20.1 kg) at a concentration of 2.5 mg of OA/kg of feed and was fed continuously for 35 days. Humoral and cell-mediated immunologic measurements were evaluated to determine the effects of OA on immune function in swine. Cutaneous basophil hypersensitivity to phytohemagglutinin (PHA), delayed hypersensitivity to tuberculin, PHA-induced lymphocyte blastogenesis, interleukin-2 production, total and isotype immunoglobulin concentrations, antibody response to chicken RBC, and macrophage activation were used to evaluate immune function. Gilts treated with OA had reduced cutaneous basophil hypersensitivity response to PHA, reduced delayed hypersensitivity to tuberculin, decreased stimulation index for lymphoblastogenesis, decreased interleukin-2 production when lymphocytes were stimulated with concanavalin A, and decreased number and phagocytic activity of macrophages. Differences were not observed for total and isotype immunoglobulin concentrations, or humoral hemagglutination (chicken RBC) titer. These data indicate that OA may suppress cell-mediated immune response in growing swine.

  2. Light colour preference of growing rabbits

    Directory of Open Access Journals (Sweden)

    Zsolt Szendrő

    2010-01-01

    Full Text Available The objective of the experiment was to evaluate the light colour preference of growing rabbits placed in a free-choice cage. The experiment was carried out on 128 Pannon White growing rabbits weaned at the age of 5 weeks and placed into blocks (2m2 of four cages. The rabbits could move freely among the four cages (0.5m2 each through swing doors. The cages differed only in the colour of the light applied (white, yellow, green or blue. The lighting schedule was 16L: 8D. From 6 until 10 weeks of age, infrared video recording was performed once a week (24 hours. The number of rabbits in each cage was counted every 15 minutes. Feed consumption was measured weekly. Between 6 and 10 weeks of age the rabbits significantly preferred white light (28.0%. The preference order was the following: yellow (26.3%, blue (23.4% and green (22.3% (P<0.001. No significant differences were recorded in the feed consumption among the cages. In conclusion, the cage preference of the rabbits was slightly affected by the light colour.

  3. Management of Infections with Rapidly Growing

    Directory of Open Access Journals (Sweden)

    Jong Hwan Kim

    2012-01-01

    Full Text Available Background Infection caused by rapidly growing mycobacteria (RGM is not uncommon, andthe prevalence of RGM infection has been increasing. Clinical diagnosis is difficult becausethere are no characteristic clinical features. There is also no standard antibiotic regimenfor treating RGM infection. A small series of patients with RGM infections was studied toexamine their treatments and outcomes.Methods A total of 5 patients who had developed postoperative infections from January2009 to December 2010 were retrospectively reviewed. Patients were initially screened using amycobacteria rapid screening test (polymerase chain reaction [PCR]-reverse blot hybridizationassay. To confirm mycobacterial infection, specimens were cultured for nontuberculousmycobacteria and analyzed by 16 S ribosomal RNA and rpoB gene PCR.Results The patients were treated with intravenous antibiotics during hospitalization,and oral antibiotics were administered after discharge. The mean duration of follow-upwas 9 months, and all patients were completely cured of infection with a regimen of acombination of antibiotics plus surgical treatment. Although none of the patients developedrecurrence, there were complications at the site of infection, including hypertrophic scarring,pigmentation, and disfigurement.Conclusions Combination antibiotic therapy plus drainage of surgical abscesses appeared tobe effective for the RGM infections seen in our patients. Although neither the exact dosagenor a standardized regimen has been firmly established, we propose that our treatment canprovide an option for the management of rapidly growing mycobacterial infection.

  4. Seasonal variation in pediatric dermatoses

    Directory of Open Access Journals (Sweden)

    Banerjee Sabyasachi

    2010-01-01

    Full Text Available Introduction: The under-five population is a unique and vulnerable component of our society that always demands special attention. Aims: Our present work aimed to study the seasonal variation, age-wise variation and distribution of lesions of common dermatoses of this age group. Materials and Methods: We clinically studied all fresh cases attending the skin OPD of our hospital for one month each from summer, rainy season and winter. Total number of patients was 879. Results: The top six skin diseases in our study were impetigo, miliaria, scabies, furunculosis, seborrheic dermatitis and papular urticaria. On statistical analysis, scabies and seborrheic dermatitis were more prevalent during winter while impetigo, furunculosis and miliaria were more during summer and rainy season. Papular urticaria was more frequent in the rainy season. Seborrheic dermatitis predominantly affected the infants while impetigo, furunculosis, miliaria and popular urticaria were commoner in older age groups. Conclusion: Distribution of lesions of common dermatoses will help diagnose difficult cases and extensive evaluation of the body parts which, by virtue of being commonly affected, are must-examine sites in under-five children.

  5. SEASONAL VARIATIONS DETERMINE DIET QUALITYTOR

    African Journals Online (AJOL)

    3 Department of Biology, BahirDar Teachers' College. PO Box 79, Bahir Dar, Ethiopia. ABSTRACT; The diet composition and its use by Oreochromis niloticus in. Lake Tana, Ethiopia, were studied from monthly samples taken over 13 months. The composition of the diet varied seasonally, with dramatic increases in quality.

  6. Seasonal Time Measurement During Reproduction

    Science.gov (United States)

    IKEGAMI, Keisuke; YOSHIMURA, Takashi

    2013-01-01

    Abstract Most species living outside the tropical zone undergo physiological adaptations to seasonal environmental changes and changing day length (photoperiod); this phenomenon is called photoperiodism. It is well known that the circadian clock is involved in the regulation of photoperiodism such as seasonal reproduction, but the mechanism underlying circadian clock regulation of photoperiodism remains unclear. Recent molecular analysis have revealed that, in mammals and birds, the pars tuberalis (PT) of the pituitary gland acts as the relay point from light receptors, which receive information about the photoperiod, to the endocrine responses. Long-day (LD)-induced thyroid-stimulating hormone (TSH) in the PT acts as a master regulator of seasonal reproduction in the ependymal cells (ECs) within the mediobasal hypothalamus (MBH) and activates thyroid hormone (TH) by inducing the expression of type 2 deiodinase in both LD and short-day (SD) breeding animals. Furthermore, the circadian clock has been found to be localized in the PT and ECs as well as in the circadian pacemaker(s). This review purposes to summarize the current knowledge concerning the involvement of the neuroendocrine system and circadian clock in seasonal reproduction. PMID:23965600

  7. ADHD, circadian rhythms and seasonality

    NARCIS (Netherlands)

    Wynchank, Dora S.; Bijlenga, Denise; Lamers, Femke; Bron, Tannetje I.; Winthorst, Wim H.; Vogel, Suzan W.; Penninx, Brenda W.; Beekman, Aartjan T.; Kooij, J. Sandra

    2016-01-01

    Objective: We evaluated whether the association between Adult Attention-Deficit/Hyperactivity Disorder (ADHD) and Seasonal Affective Disorder (SAD) was mediated by the circadian rhythm. Method: Data of 2239 persons from the Netherlands Study of Depression and Anxiety (NESDA) were used. Two groups

  8. MECHANIZATION AND THE SEASONAL FARMWORKER.

    Science.gov (United States)

    HARPER, ROBERT G.

    MECHANIZATION DOES NOT NECESSARILY DECREASE THE NUMBER OF SEASONAL FARM WORKERS NEEDED. SOME INNOVATIONS MERELY CHANGE THE JOB TO ONE THAT IS LESS UNPLEASANT, AND WORKERS FORMERLY DISINCLINED TO DO THE JOB BECOME AVAILABLE. MECHANIZATION MAY MAKE AN OPERATION SO EFFICIENT THAT ACREAGE AND PRODUCTION ARE INCREASED, AND MORE WORKERS ARE NEEDED. MUCH…

  9. Seasonality of cardiovascular risk factors

    DEFF Research Database (Denmark)

    Marti-Soler, Helena; Gubelmann, Cédric; Aeschbacher, Stefanie

    2014-01-01

    OBJECTIVE: To assess the seasonality of cardiovascular risk factors (CVRF) in a large set of population-based studies. METHODS: Cross-sectional data from 24 population-based studies from 15 countries, with a total sample size of 237 979 subjects. CVRFs included Body Mass Index (BMI) and waist...

  10. Seasonal Flu and Staph Infection

    Science.gov (United States)

    ... Avian Swine/Variant Pandemic Other Seasonal Flu and Staph Infection Questions & Answers Language: English (US) Español Recommend ... Compartir Staphylococcus aureus , often referred to simply as “staph,” are bacteria commonly carried on the skin or ...

  11. Assessing seasonality in clinical research

    NARCIS (Netherlands)

    Cleophas, Ton J.; Zwinderman, Aeilko H.

    2012-01-01

    Seasonal patterns are assumed in many fields of medicine. However, biological processes are full of variations and the possibility of chance findings can often not be ruled out. Using simulated data we assess whether auto correlation is helpful to minimize chance findings and test to support the

  12. Seasonal contributions to climate feedbacks

    Energy Technology Data Exchange (ETDEWEB)

    Colman, R. [Bureau of Meteorology Research Centre, GPO Box 1289K, Melbourne, VIC (Australia)

    2003-05-01

    Heading Abstract. This study addresses the question: how do the contributions to feedbacks in a climate model vary over the seasonal cycle? To answer this the feedbacks are evaluated from an equilibrium doubled CO{sub 2} experiment performed using the Bureau of Meteorology Research Centre (BMRC) General Circulation Model. Monthly means of the top-of-atmosphere radiative perturbations (which together comprise the annual climate feedbacks) are extracted to produce a mean annual cycle. It is found that the radiative contributions to the total longwave (LW) feedback are fairly constant throughout the year. Those to the total shortwave (SW) feedback, on the other hand, vary by a factor of three, from a maximum in July to a minimum in November. Of the LW feedbacks, contributions to the lapse rate shows greatest seasonal variation, while those to water vapour and cloud feedbacks vary by relatively small amounts throughout the year. Contributions to the lapse rate feedback as a function of surface type and latitude reveal conflicting positive and negative radiative perturbations, which vary most strongly at high latitudes. Of the SW feedbacks, contributions to both albedo and cloud show large seasonal variations. Radiative perturbations contributing to albedo feedback vary in strength with snow and sea-ice retreat which occurs at different latitudes and in different months. They are shown to be highly sensitive to the amount of incident solar radiation in a given month. SW radiative perturbations due to cloud changes vary in sign between opposite seasons. Contributions to the seasonal variations of the cloud component feedbacks, which make up the total cloud feedback, are also examined. In the LW, the feedback is dominated by the total cloud water term. Radiative perturbations due to this component show relatively little variation throughout the year. In the SW, the main source of seasonal variation occurs for contributions to the cloud amount feedback: radiative

  13. What season suits you best? Seasonal light changes and cyanobacterial competition

    Directory of Open Access Journals (Sweden)

    G. Cascallares

    2015-05-01

    Full Text Available Nearly all living organisms, including some bacterial species, exhibit biological processes with a period of about 24 h called circadian (from the Latin circa, about and dies, day rhythms. These rhythms allow living organisms to anticipate the daily alternation of light and darkness. Experiments carried out in cyanobacteria have shown the adaptive value of circadian clocks. In theseexperiments, a wild type cyanobacterial strain (with a 24 h circadian rhythm and a mutantstrain (with a longer or shorter period grow in competition. In different experiments, the external light dark cycle was chosen to match the circadian period of the different strains, revealing that the strain whose circadian period matches the light-dark cycle has a larger fitness. As a consequence, the initial population of one strain grows while the other decays. These experiments were made under fixed light and dark intervals. In Nature, however, this relationship changes according to the season. Therefore, seasonalchanges in light could affect the results of the competition. Using a theoretical model, we analyze how modulation of light can change the survival of the different cyanobacterial strains. Our results show that there is a clear shift in the competition due to the modulation of light, which could be verified experimentally. Received: 20 Novembre 2014, Accepted: 29 March 2015; Edited by: C. A. Condat, G. J. Sibona; DOI: http://dx.doi.org/10.4279/PIP.070005 Cite as: G Cascallares, P M Gleiser, Papers in Physics 7, 070005 (2015

  14. Satellite assessment of early season forecast for vegetation condition in grazing allotments in Nevada.

    Science.gov (United States)

    Fifteen years of enhanced vegetation index data from the MODIS sensor are examined in conjunction with precipitation and the Palmer drought severity index to assess how well growing season conditions for vegetation within grazing allotments of Nevada can be predicted at different times of the year. ...

  15. Seasonal and topographic effects on estimating fire severity from Landsat TM/ETM+data.

    Science.gov (United States)

    D.L. Verbyla; E.S. Kasischke; E.E. Hoy

    2008-01-01

    The maximum solar elevation is typically less than 50 degrees in the Alaskan boreal region and solar elevation varies substantially during the growing season. Because of the relatively low solar elevation at boreal latitudes, the effect of topography on spectral reflectance can influence fire severity indices derived from remotely sensed data. We used Landsat Thematic...

  16. Seasonal Biennial Burning and Woody Plant Control Influence Native Vegetation in Loblolly Pine Stands

    Science.gov (United States)

    James D. Haywood; Alton Martin; Henry A. Pearson; Harold E. Grelen

    1998-01-01

    This paper documents the results of a study to determine the effects of selectedvegetation-management treatments in loblolly pine. Vegetation in precommercially thinned, 6-year-old stands was subjected to five biennial growing season burns in either early March, May, or July coupled with hand felling of residual woody stems. Using a randomized complete block design, we...

  17. Seasonal patterns in acidity of precipitation and their implications for forest stream ecosystems

    Science.gov (United States)

    James W. Hornbeck; Gene E. Likens; John S. Eaton

    1976-01-01

    Data collected since 1965 at a network of 9 stations in the northeastern United States show that precipitation is most acid in the growing season (May-September) and least acid in winter (December-February). For the Hubbard Brook station in New Hampshire, where the mean hydrogen ion content of precipitation ranges between 46 μeq/l in winter and 102 μ...

  18. Managing cool-season weeds in sugarbeet grown for biofuel in the Southeastern U.S.

    Science.gov (United States)

    Sugarbeet, grown for biofuel, is being considered as an alternate cool-season crop in the southeastern U. S. coastal plain. Typically, the crop would be seeded in the autumn, grow through the winter, and harvested the following spring. Labels for herbicides registered for use on sugarbeet grown in ...

  19. Seasonality of Ecosystem Respiration and Gross Primary Production as Derived from Fluxnet Measurements

    Science.gov (United States)

    Falge, E.; Baldocchi, D.; Tenhunen, J.

    2001-12-01

    Differences in the seasonal pattern of assimilatory and respiratory processes are responsible for divergences in seasonal net carbon exchange among ecosystems. Using FLUXNET data (http://www-eosdis.ornl.gov/FLUXNET) we have analyzed seasonal patterns of gross primary productivity (GPP), and ecosystem respiration (RE) of boreal and temperate, deciduous and coniferous forests, mediterranean evergreen systems, rainforest, temperate grasslands, and C3 and C4 crops. Based on generalized seasonal patterns classifications of ecosystems into vegetation functional types can be evaluated for use in global productivity and climate change models. The results of this study contribute to our understanding of respiratory costs of assimilated carbon in various ecosystems. Seasonal variability of GPP and RE increased in the order tropical, Mediterranean, temperate coniferous, temperate deciduous, boreal forests. Together with boreal forests, managed grasslands and crops show the largest seasonal variability. In temperate coniferous forests, seasonal patterns of GPP and RE are in phase, in temperate deciduous and boreal coniferous forests RE was delayed compared to GPP, resulting in the greatest imbalance between respiratory and assimilatory fluxes early in the growing season. Gross primary productivity adjusted for the length of the growing season decreased across functional types in the order C4 crops, and temperate and boreal deciduous forests (7.5-8.3 g C m-2 d-1), temperate conifers, C3 grassland and crops (5.7-6.9 g C m-2 d-1), rainforest and boreal conifers (4.6-4.9 g C m-2 d-1). Annual GPP and NEP decreased across climate zones in the order tropical, temperate, boreal. However, the decrease in NEP was greater than the decrease in GPP, indicating a larger contribution of respiratory (especially heterotrophic) processes in boreal systems.

  20. Elastic plastic analysis of growing cracks

    Energy Technology Data Exchange (ETDEWEB)

    Rice, J R; Drugan, W J; Sham, T L

    1979-05-01

    The elastic--plastic stress and deformation fields at the tip of a crack which grows in an ideally plastic solid under plane strain, shows small scale yielding conditions. Results of an asymptotic analysis suggests the existence of a crack tip stress state similar to that of the classical Prandtl field, but containing a zone of elastic unloading between the centered fan region and the trailing constant stress plastic region. The near tip expression for the rate of opening displacement delta at distance r from the growing tip is found to have the form delta-. = ..cap alpha.. J-./sigma/sub o/ + ..beta..(sigma/sub o//E) a-. ln(R/r) but the presence of the elastic wedge causes ..beta.. to have the revised value of 5.08 (for Poisson ratio ..nu.. = 0.3); also, (a = crack length, sigma/sub o/ = yield strength, E = elastic modulus, and J denotes the far-field value), and (1-..nu../sup 2/)K/sup 2//E for the small scale yielding conditions considered. The parameters ..cap alpha.. and R cannot be determined from the asymptotic analysis, but comparisons with finite element solutions suggest that, for small amounts of growth, ..cap alpha.. is approximately the same for stationary and growing cracks, and R scales approximately with the size of the plastic zone, being about 15% to 30% larger. For large scale yielding, a similar form applies with possible variations in ..cap alpha.. and ..beta.., in cases which maintain triaxial constraint at the crack tip. In the fully yielded case R is expected to be proportional to the dimension of the uncracked ligament. Model crack growth criterion requiring a critical delta at some fixed r from the tip, is re-examined in light of the more accurate solution. Results suggest that the J versus ..delta..a relation describing growth is dependent on the extent of yielding. It is suggested that this dependency might be small for highly ductile materials, provided that a similar triaxial constraint is maintained in all cases.

  1. CLASSIFICATION OF TOURIST SEASON IN COSTAL TOURISM

    Directory of Open Access Journals (Sweden)

    Goran Corluka

    2016-06-01

    Full Text Available Tourism seasonality is the major characteristic of tourism industry, a well know but less understood phenomenon. Seasonal fluctuations of tourism demand are implying numerous negative implications affecting tourist destination, tourist operators and tourist demand. Almost every tourist destination is facing seasonality, but the most pronounced seasonal concentration of tourist activities have costal destinations which attract tourist demand motivated primary by the 3S – sun, sand and sea concept. Seasonality in business operation is the most challenging in tourist companies with a large share of fixed capacity, as the hotel accommodating sector. Former research of causes of seasonality, implications of seasonality and potential strategies to combat seasonality had methodological flaw. Tourism product, as a product with seasonal characteristic, requires analysis of performance by season. The objective of this paper is to classify tourist season in coastal tourist destinations regarding hotel occupancy rates. This is the first attempt to empirically classify tourist season. Sample surveys are 218 hotels located in Dalmatia, Croatia. Cluster analysis on hotel occupancy rate date was conducted, whereby the statistical significance between seasons were testes by Friedman test and the statistical significance between destinations were tested by F-test and ANOVA. Further, factor analysis was conducted to test the achieved results. Regarding the research result tourist season can be divided into three seasons: low, medium and high. Low season as the longest consisting of five months: January, February, March, November and December, middle season as the shortest consisting of three months: April, May and October and high season consisting of four months: June, July, August and September. Research findings are a significant contribution to tourism theory and practice.

  2. Linking seasonal climate forecasts with crop models in Iberian Peninsula

    Science.gov (United States)

    Capa, Mirian; Ines, Amor; Baethgen, Walter; Rodriguez-Fonseca, Belen; Han, Eunjin; Ruiz-Ramos, Margarita

    2015-04-01

    Translating seasonal climate forecasts into agricultural production forecasts could help to establish early warning systems and to design crop management adaptation strategies that take advantage of favorable conditions or reduce the effect of adverse conditions. In this study, we use seasonal rainfall forecasts and crop models to improve predictability of wheat yield in the Iberian Peninsula (IP). Additionally, we estimate economic margins and production risks associated with extreme scenarios of seasonal rainfall forecast. This study evaluates two methods for disaggregating seasonal climate forecasts into daily weather data: 1) a stochastic weather generator (CondWG), and 2) a forecast tercile resampler (FResampler). Both methods were used to generate 100 (with FResampler) and 110 (with CondWG) weather series/sequences for three scenarios of seasonal rainfall forecasts. Simulated wheat yield is computed with the crop model CERES-wheat (Ritchie and Otter, 1985), which is included in Decision Support System for Agrotechnology Transfer (DSSAT v.4.5, Hoogenboom et al., 2010). Simulations were run at two locations in northeastern Spain where the crop model was calibrated and validated with independent field data. Once simulated yields were obtained, an assessment of farmer's gross margin for different seasonal climate forecasts was accomplished to estimate production risks under different climate scenarios. This methodology allows farmers to assess the benefits and risks of a seasonal weather forecast in IP prior to the crop growing season. The results of this study may have important implications on both, public (agricultural planning) and private (decision support to farmers, insurance companies) sectors. Acknowledgements Research by M. Capa-Morocho has been partly supported by a PICATA predoctoral fellowship of the Moncloa Campus of International Excellence (UCM-UPM) and MULCLIVAR project (CGL2012-38923-C02-02) References Hoogenboom, G. et al., 2010. The Decision

  3. Seasonal Shifts in Diet and Gut Microbiota of the American Bison (Bison bison.

    Directory of Open Access Journals (Sweden)

    Gaddy T Bergmann

    Full Text Available North American bison (Bison bison are becoming increasingly important to both grassland management and commercial ranching. However, a lack of quantitative data on their diet constrains conservation efforts and the ability to predict bison effects on grasslands. In particular, we know little about the seasonality of the bison diet, the degree to which bison supplement their diet with eudicots, and how changes in diet influence gut microbial communities, all of which play important roles in ungulate performance. To address these knowledge gaps, we quantified seasonal patterns in bison diet and gut microbial community composition for a bison herd in Kansas using DNA sequencing-based analyses of both chloroplast and microbial DNA contained in fecal matter. Across the 11 sampling dates that spanned 166 days, we found that diet shifted continuously over the growing season, allowing bison to take advantage of the seasonal availability of high-protein plant species. Bison consumed more woody shrubs in spring and fall than in summer, when forb and grass intake predominated. In examining gut microbiota, the bacterial phylum Tenericutes shifted significantly in relative abundance over the growing season. This work suggests that North American bison can continuously adjust their diet with a high reliance on non-grasses throughout the year. In addition, we find evidence for seasonal patterns in gut community composition that are likely driven by the observed dietary changes.

  4. Dietary supplementation of butyrate in growing rabbits

    Directory of Open Access Journals (Sweden)

    G. Radaelli

    2010-01-01

    Full Text Available The UE restrictions imposed on the antibiotic utilization in animal husbandry have increased the interest on alternative additives capable of improving animal digestive health. Among the numerous tested products, short chain fatty acids stimulated intestinal mucus production at different level and intestinal cells proliferation in rats (Meslin et al., 2001; Moreau et al., 2003. Short and medium chain fatty acids could also modulate intestinal microflora: in rabbits, the antimicrobial activity of caprilic and capric acids was proved on various strains of Clostridium perfringens and Escherichia coli (Marounek et al., 2002. The present trial aimed to evaluate the effect of butyrate inclusion and level on growth performance, health status, digestive physiology and slaughter traits in growing rabbits.

  5. Morphogenesis of filaments growing in flexible confinements

    Science.gov (United States)

    Vetter, R.; Wittel, F. K.; Herrmann, H. J.

    2014-07-01

    Space-saving design is a requirement that is encountered in biological systems and the development of modern technological devices alike. Many living organisms dynamically pack their polymer chains, filaments or membranes inside deformable vesicles or soft tissue-like cell walls, chorions and buds. Surprisingly little is known about morphogenesis due to growth in flexible confinements—perhaps owing to the daunting complexity lying in the nonlinear feedback between packed material and expandable cavity. Here we show by experiments and simulations how geometric and material properties lead to a plethora of morphologies when elastic filaments are growing far beyond the equilibrium size of a flexible thin sheet they are confined in. Depending on friction, sheet flexibility and thickness, we identify four distinct morphological phases emerging from bifurcation and present the corresponding phase diagram. Four order parameters quantifying the transitions between these phases are proposed.

  6. THE FASTEST GROWING LEAST DEVELOPED COUNTRIES

    Directory of Open Access Journals (Sweden)

    Wioletta NOWAK

    2017-12-01

    Full Text Available The paper presents trends in economic growth and development in twelve least developed countries from 2006 to 2015. The study is based on the data retrieved from the World Bank Database. During the analysed 10 years, seven Asian (Myanmar, Lao PDR, Bhutan, Cambodia, Timor-Leste, Bangladesh, and Afghanistan and five African (Ethiopia, Rwanda, Angola, Sudan, and Mozambique LDCs had average annual GDP per capita growth rates higher than 4.0%. GDP has been largely generated through the services and industry sectors. A few LDCs sustained strong growth mainly because of foreign assistance and in other countries remittances were a significant source of development finance. Resource rich countries recorded high inflows of foreign direct investment. In a few fast growing LDCs the state has been heavily engaged in economy. The analysed LDCs substantially improved their development indicators.

  7. Tropical tree water use under seasonal waterlogging and drought in central Cambodia

    Science.gov (United States)

    Miyazawa, Yoshiyuki; Tateishi, Makiko; Komatsu, Hikaru; Ma, Vuthy; Kajisa, Tsuyoshi; Sokh, Heng; Mizoue, Nobuya; Kumagai, Tomo'omi

    2014-07-01

    In central Cambodia, rapid growing non-endemic species are planted for future timber production. However, less is understood about the impact of the introduction of non-endemic species on the transpiration characteristics of the forest, which has been composed of native species that adapted to the highly seasonal environments. Sap flux of two native and one non-endemic tree species in central Cambodia was measured to reveal its seasonal trends and variability in the Monsoon Asia region. Measurements were carried out in a 10- to 15-year-old forest in the dry and rainy seasons that were defined by differing rainfall patterns. The seasonal trend in depth to water table differed from that of rainfall; groundwater table depth reached zero late in the rainy season and increased gradually after the onset of the dry season. The ratio of sap flux to an equilibrium evaporation condition of the native species, Popel (Shorea roxburghii), showed a sharp decline at the end of the dry season, whereas that of a non-endemic species, eucalyptus (Eucalyptus camaldulensis), decreased in the mid rainy season while Tbeng (Dipterocarpus obtusifolius) did not show a clear trend. The ratio of sap flux to an equilibrium evaporation was negatively correlated with the depth to water table in Popel, but was positively correlated in eucalyptus, possibly because of the negative effects of flooding. In addition to the large seasonal variation, intra-species variation in sap flux was also large and was a major controlling factor for tree-level water uptake at this young forest site in both dry and rainy seasons. In conclusion, the transpiration characteristics of this forest were species-specific and were controlled more by the fluctuating depths to groundwater rather than the onset of the rainy/dry seasons defined by rainfall events.

  8. Feed efficiency metrics in growing pigs.

    Science.gov (United States)

    Calderón Díaz, J A; Berry, D P; Rebeiz, N; Metzler-Zebeli, B U; Magowan, E; Gardiner, G E; Lawlor, P G

    2017-07-01

    The objective of the present study was to quantify the interrelationships between different feed efficiency measures in growing pigs and characterize pigs divergent for a selection of these measures. The data set included data from 311 growing pigs between 42 and 91 d of age from 3 separate batches. Growth-related metrics available included midtest metabolic BW (BW), energy intake (EI), and ADG. Ratio efficiency traits included energy conversion ratio (ECR), Kleiber ratio (ADG/BW), relative growth rate (RGR), residual EI (REI), and residual daily gain (RDG). Residual intake and gain (RIG; i.e., a dual index of both REI and RDG) and residual midtest metabolic weight (RMW) were also calculated. Simple Pearson correlations were estimated between the growth and feed efficiency metrics. In litters with at least 3 pigs of each sex, pigs were separately stratified on each residual trait as high, medium, and low rank. Considerable interanimal variability existed in all metrics evaluated. Male pigs were superior to females for all metrics ( efficiency metrics improved as birth BW increased ( efficiency metrics were strong to moderate ( efficient) had lower EI and ECR and were superior for RIG ( efficient) had greater BW gain and better ECR ( Energy conversion ratio, REI, and RIG were superior ( efficient) compared with medium-RMW pigs. High-RIG pigs (i.e., more efficient) had lower EI ( efficiency traits investigated in this study were different from unity, indicating that each trait is depicting a different aspect of efficiency in pigs, although the moderate to strong correlations suggest that improvement in one trait would, on average, lead to improvements in the others. Pigs ranked as more efficient on residual traits such as REI consumed less energy for a similar BW gain, which would translate into an economic benefit for pig producers.

  9. Effect of sow history features on growth and feed intake in grow-finish pigs.

    Science.gov (United States)

    Sell-Kubiak, E; Knol, E F; Bijma, P

    2012-01-01

    The sow provides a specific environment to her offspring during gestation and lactation. Certain features in the early life of the sow (sow history features) may affect her ability to deliver and feed a healthy litter. In genetic analyses of grow-finish traits, these effects are estimated as common litter or permanent sow effects. The objective of this research was to identify sow history features that affect the growth rate (GR) and feed intake (FI) of her offspring during the grow-finish stage. Data from 17,743 grow-finish pigs, coming from 604 sires and 681 crossbred sows, were recorded between May 2001 and February 2010 at the experimental farm of the Institute for Pig Genetics (Beilen, the Netherlands). The grow-finish stage was divided into 2 phases (phase 1: 26 to 75 kg; phase 2: 75 to 115 kg). The sow history features were birth litter size, birth year and season, birth farm, weaning age, age of transfer to the experimental farm, and age at first insemination. The sow features were added to the basic model one at a time to study their effect on the grow-finish traits of the pigs. Subsequently, significant sow features (P piglet in the birth litter of the sow, the GR of her offspring decreased by 1 g/d and the FI decreased by 4 g/d. Every extra day to the first insemination increased the GR of grow-finish pigs by 0.1 g/d. The heritability estimates for GR and FI (only in phase 2 of the grow-finish stage) decreased after adding the sow features to the model. No differences were found in estimates of the common litter effects between the basic model and the model with all significant sow features. The estimates of the permanent sow effect changed for FI from 0.03 (basic model) to 0.00 (model with sow features), and for FI in phase 1, the permanent sow effect decreased from 0.03 (basic model) to 0.01 (model with sow features). In conclusion, selected sow features do affect the grow-finish traits of the pigs, but their estimates are small and explain only a

  10. Seasonal and diurnal variations in methane emissions from Wuliangsu Lake in arid regions of China

    Science.gov (United States)

    Duan, Xiaonan; Wang, Xiaoke; Mu, Yujing; Ouyang, Zhiyun

    CH 4 emissions have been widely studied in various wetlands, such as boreal peatlands, rice paddies, and tropical swamps. However, little investigation has been carried out for CH 4 emissions from lakes or wetlands in arid regions where these freshwaters play a vital role in providing ecosystem services for local people. To quantify the spatial and temporal variations of CH 4 flux and understand its key controlling factors in shallow lakes in arid regions of Western China, CH 4 fluxes from Wuliangsu Lake were measured at different vegetation zones and water depths with a static chamber technique during a growing season from April to October in 2003. Results showed that the average emission flux of CH 4 from submerged plant ( Potamogeton pectinatus) growing zones was 2.16 mg CH 4 m -2 h -1, which was 85.8% lower than that from emergent macrophyte ( Phragmites australis) growing zones. CH 4 emissions increased with increasing water depth in Phragmites Community. Significant seasonal and diurnal variations of CH 4 emission were observed for P. australis during the plant growth stage, for P. pectinatus growing zones, however, the variations were minor. In addition to vegetation cover and water depth, bottom silt temperature and light intensity were also important factors influencing seasonal and diurnal variations of CH 4 flux from Phargmites growing zone.

  11. The Correlation between Thermal and Noxious Gas Environments, Pig Productivity and Behavioral Responses of Growing Pigs

    Directory of Open Access Journals (Sweden)

    Won Kyung Chang

    2011-08-01

    Full Text Available Correlations between environmental parameters (thermal range and noxious gas levels and the status (productivity, physiological, and behavioral of growing pigs were examined for the benefit of pig welfare and precision farming. The livestock experiment was conducted at a Seoul National University station in South Korea. Many variations were applied and the physiological and behavioral responses of the growing pigs were closely observed. Thermal and gas environment parameters were different during the summer and winter seasons, and the environments in the treatments were controlled in different manners. In the end, this study finds that factors such as Average Daily Gain (ADG, Adrenocorticotropic Hormone (ACTH, stress, posture, and eating habits were all affected by the controlled environmental parameters and that appropriate control of the foregoing could contribute to the improvement of precision farming and pig welfare.

  12. Influence of the Growing Conditions in the Content of Vitamin C in Diplotaxis erucoides

    Directory of Open Access Journals (Sweden)

    Carla GUIJARRO-REAL

    2017-11-01

    Full Text Available Diplotaxis erucoides is an edible plant with potential for marketing. Here, we analysed the influence of the growing conditions in this species, D. tenuifolia and Eruca sativa, and studied the relation among the ascorbic (AA and dehydroascorbic (DHA acid forms. Plants were grown in the late winter-spring season under two conditions, greenhouse and field. The contents in AA, DHA and vitamin C (VC were analysed by HPLC. The content of VC and AA were, in general, remarkable higher in the plants grown in the field. On the other hand, the mean percentage of DHA was less than 11%, being in this case higher for plants grown in the greenhouse. Thus, growing this potential crop in the field seems a better option in order to increase the content in VC, being AA the main form present at the moment of gathering.

  13. A seasonal variation of calcitropic hormones, bone turnover and bone mineral density in early and mid-puberty girls - a cross-sectional study

    DEFF Research Database (Denmark)

    Viljakainen, H.T.; Palssa, A.; Karkkainen, M.

    2006-01-01

    The importance of the seasonal variation of calcitropic hormones to growing skeleton has not been established. We studied whether there exists a seasonal variation in calcitropic hormones, bone mineral density (BMD) and bone remodelling markers in early puberty girls. One hundred and ninety...

  14. season.

    African Journals Online (AJOL)

    CONSERVATIVE ... Water and salt budgets suggest that in order to balance the inflow and outflow of water at. Makoba bay, there is net flux of water from ..... Department of Aquatic Environment and Conservation,. University of Dar es Salaam,.

  15. Why this growing atrocities on women?

    Science.gov (United States)

    Batra, N D

    After a summary of the prehistoric origins of the low status of women, the present state of women is reviewed and some suggestions for India are proposed. Women got into their present low status as homemakers because of the invention of fire which made them evolve into the weaker sex. The phenomenon of rape arose because leisure gave men the opportunity to indulge in sexuality outside of a mating season. This lead to early marriage and domination of women by father, husband and sons. Now India has fewer hospital facilities for women. Women can only achieve status by bearing sons. Women do all the domestic work, raise half the world's food, earn less than men and are underrepresented in decision-making. Dowry deaths, humiliation, torture and violence toward women are a national disgrace. Legislation alone will not stop dowry abuse. Attitudes must be changed by restructuring the educational system. Anti-dowry squads should be formed to prevent expensive weddings. Legal aid should be provided to victims and kin of dowry abuse. Men proven guilty of murdering their wives should be forbidden to remarry. The single law that would do most for women is to give them the right to property.

  16. Environmental Growing Conditions in Five Production Systems Induce Stress Response and Affect Chemical Composition of Cocoa (Theobroma cacao L.) Beans.

    Science.gov (United States)

    Niether, Wiebke; Smit, Inga; Armengot, Laura; Schneider, Monika; Gerold, Gerhard; Pawelzik, Elke

    2017-11-29

    Cocoa beans are produced all across the humid tropics under different environmental conditions provided by the region but also by the season and the type of production system. Agroforestry systems compared to monocultures buffer climate extremes and therefore provide a less stressful environment for the understory cocoa, especially under seasonally varying conditions. We measured the element concentration as well as abiotic stress indicators (polyamines and total phenolic content) in beans derived from five different production systems comparing monocultures and agroforestry systems and from two harvesting seasons. Concentrations of N, Mg, S, Fe, Mn, Na, and Zn were higher in beans produced in agroforestry systems with high stem density and leaf area index. In the dry season, the N, Fe, and Cu concentration of the beans increased. The total phenolic content increased with proceeding of the dry season while other abiotic stress indicators like spermine decreased, implying an effect of the water availability on the chemical composition of the beans. Agroforestry systems did not buffer the variability of stress indicators over the seasons compared to monocultures. The effect of environmental growing conditions on bean chemical composition was not strong but can contribute to variations in cocoa bean quality.

  17. Greater deciduous shrub abundance extends tundra peak season and increases modeled net CO2 uptake.

    Science.gov (United States)

    Sweet, Shannan K; Griffin, Kevin L; Steltzer, Heidi; Gough, Laura; Boelman, Natalie T

    2015-06-01

    Satellite studies of the terrestrial Arctic report increased summer greening and longer overall growing and peak seasons since the 1980s, which increases productivity and the period of carbon uptake. These trends are attributed to increasing air temperatures and reduced snow cover duration in spring and fall. Concurrently, deciduous shrubs are becoming increasingly abundant in tundra landscapes, which may also impact canopy phenology and productivity. Our aim was to determine the influence of greater deciduous shrub abundance on tundra canopy phenology and subsequent impacts on net ecosystem carbon exchange (NEE) during the growing and peak seasons in the arctic foothills region of Alaska. We compared deciduous shrub-dominated and evergreen/graminoid-dominated community-level canopy phenology throughout the growing season using the normalized difference vegetation index (NDVI). We used a tundra plant-community-specific leaf area index (LAI) model to estimate LAI throughout the green season and a tundra-specific NEE model to estimate the impact of greater deciduous shrub abundance and associated shifts in both leaf area and canopy phenology on tundra carbon flux. We found that deciduous shrub canopies reached the onset of peak greenness 13 days earlier and the onset of senescence 3 days earlier compared to evergreen/graminoid canopies, resulting in a 10-day extension of the peak season. The combined effect of the longer peak season and greater leaf area of deciduous shrub canopies almost tripled the modeled net carbon uptake of deciduous shrub communities compared to evergreen/graminoid communities, while the longer peak season alone resulted in 84% greater carbon uptake in deciduous shrub communities. These results suggest that greater deciduous shrub abundance increases carbon uptake not only due to greater leaf area, but also due to an extension of the period of peak greenness, which extends the period of maximum carbon uptake. © 2015 John Wiley & Sons Ltd.

  18. Seasonal Changes in Titan's Meteorology

    Science.gov (United States)

    Turtle, E. P.; DelGenio, A. D.; Barbara, J. M.; Perry, J. E.; Schaller, E. L.; McEwen, A. S.; West, R. A.; Ray, T. L.

    2011-01-01

    The Cassini Imaging Science Subsystem has observed Titan for 1/4 Titan year, and we report here the first evidence of seasonal shifts in preferred locations of tropospheric methane clouds. South \\polar convective cloud activity, common in late southern summer, has become rare. North \\polar and northern mid \\latitude clouds appeared during the approach to the northern spring equinox in August 2009. Recent observations have shown extensive cloud systems at low latitudes. In contrast, southern mid \\latitude and subtropical clouds have appeared sporadically throughout the mission, exhibiting little seasonality to date. These differences in behavior suggest that Titan s clouds, and thus its general circulation, are influenced by both the rapid temperature response of a low \\thermal \\inertia surface and the much longer radiative timescale of Titan s cold thick troposphere. North \\polar clouds are often seen near lakes and seas, suggesting that local increases in methane concentration and/or lifting generated by surface roughness gradients may promote cloud formation. Citation

  19. Evaluation of seasonal variations of remotely sensed leaf area index over five evergreen coniferous forests

    Science.gov (United States)

    Wang, Rong; Chen, Jing M.; Liu, Zhili; Arain, Altaf

    2017-08-01

    Seasonal variations of leaf area index (LAI) have crucial controls on the interactions between the land surface and the atmosphere. Over the past decades, a number of remote sensing (RS) LAI products have been developed at both global and regional scales for various applications. These products are so far only validated using ground LAI data acquired mostly in the middle of the growing season. The accuracy of the seasonal LAI variation in these products remains unknown and there are few ground data available for this purpose. We performed regular LAI measurements over a whole year at five coniferous sites using two methods: (1) an optical method with LAI-2000 and TRAC; (2) a direct method through needle elongation monitoring and litterfall collection. We compared seasonal trajectory of LAI from remote sensing (RS LAI) with that from a direct method (direct LAI). RS LAI agrees very well with direct LAI from the onset of needle growth to the seasonal peak (R2 = 0.94, RMSE = 0.44), whereas RS LAI declines earlier and faster than direct LAI from the seasonal peak to the completion of needle fall. To investigate the possible reasons for the discrepancy, the MERIS Terrestrial Chlorophyll Index (MTCI) was compared with RS LAI. Meanwhile, phenological metrics, i.e. the start of growing season (SOS) and the end of growing season (EOS), were extracted from direct LAI, RS LAI and MTCI time series. SOS from RS LAI is later than that from direct LAI by 9.3 ± 4.0 days but earlier than that from MTCI by 2.6 ± 1.9 days. On the contrary, for EOS, RS LAI is later than MTCI by 3.3 ± 8.4 days and much earlier than direct LAI by 30.8 ± 7.2 days. Our results suggest that the seasonal trajectory of RS LAI well captures canopy structural information from the onset of needle growth to the seasonal peak, but is greatly influenced by the decrease in leaf chlorophyll content, as indicated by MTCI, from the seasonal peak to the completion of needle fall. These findings have significant

  20. Seasonal Nitrogen Cycles on Pluto

    Science.gov (United States)

    Hansen, Candice J.; Paige, David A.

    1996-01-01

    A thermal model, developed to predict seasonal nitrogen cycles on Triton, has been modified and applied to Pluto. The model was used to calculate the partitioning of nitrogen between surface frost deposits and the atmosphere, as a function of time for various sets of input parameters. Volatile transport was confirmed to have a significant effect on Pluto's climate as nitrogen moved around on a seasonal time scale between hemispheres, and sublimed into and condensed out of the atmosphere. Pluto's high obliquity was found to have a significant effect on the distribution of frost on its surface. Conditions that would lead to permanent polar caps on Triton were found to lead to permanent zonal frost bands on Pluto. In some instances, frost sublimed from the middle of a seasonal cap outward, resulting in a "polar bald spot". Frost which was darker than the substrate did not satisfy observables on Pluto, in contrast to our findings for Triton. Bright frost (brighter than the substrate) came closer to matching observables. Atmospheric pressure varied seasonally. The amplitudes, and to a lesser extent the phase, of the variation depended significantly on frost and substrate properties. Atmospheric pressure was found to be determined both by Pluto's distance from the sun and by the subsolar latitude. In most cases two peaks in atmospheric pressure were observed annually: a greater one associated with the sublimation of the north polar cap just as Pluto receded from perihelion, and a lesser one associated with the sublimation of the south polar cap as Pluto approached perihelion. Our model predicted frost-free dark substrate surface temperatures in the 50 to 60 K range, while frost temperatures typically ranged between 30 to 40 K. Temporal changes in frost coverage illustrated by our results, and changes in the viewing geometry of Pluto from the Earth, may be important for interpretation of ground-based measurements of Pluto's thermal emission.

  1. Seasonal obsessive-compulsive disorder

    Directory of Open Access Journals (Sweden)

    Prakriti Sinha

    2014-01-01

    Full Text Available A case of obsessive-compulsive disorder (OCD with seasonal variation in symptoms of 10-years duration is reported because of its rarity. The phenomenology of the observed disorder was obsessions related to dirt and contamination resulting in washing compulsions with onset in October and complete resolution in April-May every year. The patient responded to phototherapy along with exposure and response prevention therapy and pharmacotherapy.

  2. A Multi-Refuge Study to Evaluate the Effectiveness of Growing-Season and Dormant-Season Burns to Control Cattail

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Proliferation of invasive cattails (for example, Typha x glauca, T. angustifolia) is a concern of wetland managers across the country, and numerous methods have been...

  3. Seasonal exports and drivers of dissolved inorganic and organic carbon, carbon dioxide, methane and δ13C signatures in a subtropical river network.

    Science.gov (United States)

    Atkins, Marnie L; Santos, Isaac R; Maher, Damien T

    2017-01-01

    Riverine systems act as important aquatic conduits for carbon transportation between atmospheric, terrestrial and oceanic pools, yet the magnitude of these exports remain poorly constrained. Interconnected creek and river sites (n=28) were sampled on a quarterly basis in three subcatchments of the subtropical Richmond River Catchment (Australia) to investigate spatial and temporal dynamics of dissolved inorganic carbon (DIC), dissolved organic carbon (DOC), carbon dioxide (CO2), methane (CH4), and carbon stable isotope ratios (δ13C). The study site is an area of high interest due to potential unconventional gas (coal seam gas or coal bed methane) development. DIC exports were driven by groundwater discharge with a small contribution by in situ DOC remineralization. The DIC exports showed seasonal differences ranging from 0.10 to 0.27mmolm-2catchmentd-1 (annual average 0.17mmolm-2catchmentd-1) and peaked during winter when surface water discharge was highest. DOC exports (sourced from terrestrial organic matter) had an annual average 0.07mmolm-2catchmentd-1 and were 1 to 2 orders of magnitude higher during winter compared to spring and summer. CO2 evasion rates (annual average of 347mmolm-2water aread-1) were ~2.5 fold higher during winter compared to spring. Methane was always supersaturated (0.19 to 62.13μM), resulting from groundwater discharge and stream-bed methanogenesis. Methane evasion was highly variable across the seasons with an annual average of 3.05mmolm-2water aread-1. During drier conditions, stable isotopes implied enhanced CH4 oxidation. Overall, carbon losses from the catchment were dominated by CO2 evasion (60%) followed by DIC exports (30%), DOC exports (9%) and CH4 evasion (groundwater discharge and rain events controlled carbon exports. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Segregation of chromosome arms in growing and non-growing Escherichia coli cells

    DEFF Research Database (Denmark)

    Woldringh, Conrad L.; Hansen, Flemming G.; Vischer, Norbert O. E.

    2015-01-01

    In slow-growing Escherichia coli cells the chromosome is organized with its left (L) and right (R) arms lying separated in opposite halves of the nucleoid and with the origin (0) in-between, giving the pattern L-O-R. During replication one of the arms has to pass the other to obtain the same...

  5. Growing Youth Growing Food: How Vegetable Gardening Influences Young People's Food Consciousness and Eating Habits

    Science.gov (United States)

    Libman, Kimberly

    2007-01-01

    Much attention is currently being paid to rising rates of obesity, especially among youth. In this context, garden-based education can have a role in improving public health. A qualitative study conducted at the Brooklyn Botanic Garden (BBG) Children's Garden provides supporting evidence for the claim that growing vegetables can improve the…

  6. Thyroid hormone and seasonal rhythmicity

    Directory of Open Access Journals (Sweden)

    Hugues eDardente

    2014-02-01

    Full Text Available Living organisms show seasonality in a wide array of functions such as reproduction, fattening, hibernation and migration. At temperate latitudes, changes in photoperiod maintain the alignment of annual rhythms with predictable changes in the environment. The appropriate physiological response to changing photoperiod in mammals requires retinal detection of light and pineal secretion of melatonin, but extraretinal detection of light occurs in birds. A common mechanism across all vertebrates is that these photoperiod-regulated systems alter hypothalamic thyroid hormone conversion. Here we review the evidence that a circadian clock within the pars tuberalis of the adenohypophysis links photoperiod decoding to local changes of thyroid hormone signalling within the medio-basal hypothalamus through a conserved thyrotropin/deiodinase axis. We also focus on recent findings which indicate that, beyond the photoperiodic control of its conversion, thyroid hormone might also be involved in longer term timing processes of seasonal programs. Finally, we examine the potential implication of kisspeptin and RFRP3, two RF-amide peptides expressed within the medio-basal hypothalamus, in seasonal rhythmicity.

  7. Wartime diet for growing bobwhite quail

    Science.gov (United States)

    Nestler, R.B.; Llewellyn, L.; Benner, M.

    1944-01-01

    Two experiments, using 784 bobwhite quail chicks, were conducted at the Patuxent Research Refuge, Bowie, Maryland, to find a growing diet that would meet wartime restrictions. In 1941 a diet containing 14 per cent sardine fish meal was formulated and gave satisfactory results from the standpoints of survival and growth. Since fish meal now is scarce, search was made for a diet without war-restricted commodities yet equal to the above-mentioned diet in feeding value. Ten diets were compared.....In the present experiments, quail fed this same diet modified by the substitution of 0.12 per cent of D-activated sterol for vitamin A and D feeding oil fortified showed the highest survival and the best live weights at the end of both the sixth and tenth weeks. They also were among the top three groups in requiring the least quantity of feed per unit of gain in weight; however, they consumed the greatest quantity of feed.....Of the other nine diets, that which seemed most promising, considering survival, live weight, and efficiency of feed utilization, was as follows (parts by weight) : Yellow corn, ground 26.08...Millet, ground 10.00...Alfalfa leaf meal, dehydrated 7.50...Soybean oil meal, solvent-processed 50.00...Dried whey 3.00...Special steamed bonemeal 1.50...Limestone, ground 0.80...Salt mixture 1.OO...D-activated animal sterol 0.12....100.00.....At the end of ten weeks the results on this diet (Diet l l ) , as compared with that containing sardine meal (Diet 23), were as follows: Diet No. 11 Percentage survival 71, Average live weight per bird, grams 144,....Growing mash consumed, per bird-day, grams 6.8 Feed consumed per gram of gain in weight (grams) 3.8......Diet 23....Percentage survival, 80,...Avg live weight per bird, grams....145,....Growing mash consumed , per bird-day, grams...7.4...Feed consumed per gram of gain in weight (grams)....3.9. Results were unsatisfactory when expeller-processed soybean oil meal was used in this diet to replace solvent

  8. Fluzone High-Dose Seasonal Influenza Vaccine

    Science.gov (United States)

    ... Variant Pandemic Other Fluzone High-Dose Seasonal Influenza Vaccine Questions & Answers Language: English (US) Español Recommend on ... flu season. What is Fluzone High-Dose influenza vaccine? Fluzone High-Dose is an influenza vaccine, manufactured ...

  9. Light Therapy Boxes for Seasonal Affective Disorder

    Science.gov (United States)

    Seasonal affective disorder treatment: Choosing a light therapy box Light therapy boxes can offer an effective treatment for seasonal affective disorder. Features such as light intensity, safety, cost and ...

  10. Seasonal variation of secondary cosmic rays in the low polar atmosphere

    Science.gov (United States)

    Germanenko, Alexey; Balabin, Yury

    Monitoring of different kind of secondary cosmic rays in the low atmosphere is carried out for some years in the Polar Geophysical Institute. At the present moment two monitoring stations (Apatity, Murmansk region and Barentsburg, Spitzbergen) are in operation. Additionally to conventional 18-NM-64 neutron monitor (NM) there are leadless 4-NM-64 section (LLNM), thermal neutron detector (TND) and scintillation detector of gamma-ray (SDG) of 20-400 keV energy range. SDG has 5 cm lead shield at bottom and sides, accepts radiation only from the atmosphere. In a row of neutron detectors from NM to TND seasonal variation grows up from 0 to ˜ 10 %. The distinct and big seasonal variation (˜ 30 %) is on SDG detector. Low energy gamma-rays are caused of pion and muon decay, first of all low energy muons. It was suggested muon seasonal variation, depending on atmosphere temperature and seasonal condition, determines the SDG-variation.

  11. Seasonal and genetic influences on sex expression in a backcrossed segregating papaya population.

    Directory of Open Access Journals (Sweden)

    Alexandre Pio Viana

    2011-01-01

    Full Text Available This study aimed to evaluate the genetic and seasonal influence on sex expression in segregating generationsof papaya elite and backcrossed genotypes. In the four seasons of the 2005/2006 growing season, 200 hermaphrodite plantswere evaluated. Of the eight studied traits, four were related to flowering and four to fruiting, i.e., to the percentage of normal,deformed, sterile, and total number of flowers, as well as the percentage of total, carpelloid, pentandric, and marketablefruits. Significant differences due to the genotype x season interaction were verified. Based on the genotypic determinationcoefficient and the variation index it was concluded that winter and spring are most appropriate for the selection of superiorgenotypes. Thus, selection in early stages of plant development is more successful, indicating that the physiological age mayalso be a factor involved in the expression of the above traits.

  12. Climatic growing conditions of Jatropha curcas L.

    Energy Technology Data Exchange (ETDEWEB)

    Maes, W.H.; Achten, W.M.J.; Muys, B. [Katholieke Universiteit Leuven, Division Forest, Nature and Landscape, Celestijnenlaan 200 E Box 2411, BE-3001 Leuven (Belgium); Trabucco, A. [Katholieke Universiteit Leuven, Division Forest, Nature and Landscape, Celestijnenlaan 200 E Box 2411, BE-3001 Leuven (Belgium); International Water Management Institute (IWMI), P.O. Box 2075, Colombo (Sri Lanka)

    2009-10-15

    The massive investment in new jatropha plantations worldwide is not sufficiently based on a profound scientific knowledge of its ecology. In this article, we define the climatic conditions in its area of natural distribution by combining the locations of herbarium specimens with corresponding climatic information, and compare these conditions with those in 83 jatropha plantations worldwide. Most specimens (87%) were found in tropical savannah and monsoon climates (A{sub m}, A{sub w}) and in temperate climates without dry season and with hot summer (C{sub fa}), while very few were found in semi-arid (B{sub S}) and none in arid climates (B{sub W}). Ninety-five percent of the specimens grew in areas with a mean annual rainfall above 944 mm year{sup -1} and an average minimum temperature of the coldest month (T{sub min}) above 10.5 C. The mean annual temperature range was 19.3-27.2 C. The climatic conditions at the plantations were different from those of the natural distribution specimens for all studied climatic variables, except average maximum temperature in the warmest month. Roughly 40% of the plantations were situated in regions with a drier climate than in 95% of the area of the herbarium specimens, and 28% of the plantations were situated in areas with T{sub min} below 10.5 C. The observed precipitation preferences indicate that jatropha is not common in regions with arid and semi-arid climates. Plantations in arid and semi-arid areas hold the risk of low productivity or irrigation requirement. Plantations in regions with frost risk hold the risk of damage due to frost. (author)

  13. Growing pains: twelve lessons from corporate restructuring.

    Science.gov (United States)

    Gill, S L; Johnson, R L

    1988-05-01

    Corporate reorganization is a realignment of resources to enhance competitive strength and can follow one of two lines, vertical or horizontal. Whichever strategy is used, the reason for it remains unchanged: to provide a structural hierarchy through which strategic market niches are acquired and resources are economically deployed throughout the system. Healthcare corporate restructuring, however, is encountering growing pains, some of which were inevitable and others avoidable. When the healthcare organizational landscape is surveyed, 12 lessons can be learned about corporate reorganization: 1. Reorganization should be based on anticipated market and environmental conditions. 2. Form follows function. 3. Interdependence among multiple corporate units must be clearly acknowledged. 4. Reorganization is much more costly and politically charged than it appears at first. Reserved rights must be clearly defined. 6. The purpose and composition of the parent governing board must be distinguished from those of subsidiary boards. 7. Clarification of roles and relationships between the parent and subsidiaries is critical. 8. Unrealistic expectations of success should be confronted through up-front planning, negotiation, and creative problem solving. 9. False assumptions about corporate staffing needs create internal system warfare. 10. Physician support is crucial for success. 11. Hospital-based management skills and understanding may be inadequate for making personnel decisions in subsidiaries other than the hospital. 12. Competitive strategies must be strategically determined and must not be taken gamesmanship.

  14. Autoethnography in Health Research: Growing Pains?

    Science.gov (United States)

    Chang, Heewon

    2016-03-01

    Autoethnography is gaining acceptance as a legitimate research method in health science research. The growing volume of published autoethnographies is indicative of this trend. After discussing the methodological tenents of this qualitative research method and its compatibility with health-related research, the author illustrates this trend with examples of published autoethnogrpahic books, theses, and journal articles. While celebrating the potential of autoethnography as a suitable health research method, the author critiques dominatly descriptive and evocative illness self-narratives that may evoke emontionally compelling responses from readers but offer insufficient sociocultural insights about the illness phenomenon. To identify a "desirable" autoethnography that provides not only a "thick description" of personal experiences but also a sociocultural interpration of such experiences, the author recommends both creators and consumers of autoethnography to ask five evaluative questions: (1) Does the autoethnography use authentic and trustworthy data?; (2) Does the autoethnography follow a reliable research process and show the process clearly?; (3) Does the autoethnography follow ethical steps to protect the rights of self and others presented and implicated in the autoethnography?; (4) Does the autoethnography analyze and interpret the sociocultural meaning of the author's personal experiences?; and (5) Does the autoethnography attempt to make a scholarly contribution with its conclusion and engagement of the existing literature? © The Author(s) 2016.

  15. Growing duckweed for biofuel production: a review.

    Science.gov (United States)

    Cui, W; Cheng, J J

    2015-01-01

    Duckweed can be utilised to produce ethanol, butanol and biogas, which are promising alternative energy sources to minimise dependence on limited crude oil and natural gas. The advantages of this aquatic plant include high rate of nutrient (nitrogen and phosphorus) uptake, high biomass yield and great potential as an alternative feedstock for the production of fuel ethanol, butanol and biogas. The objective of this article is to review the published research on growing duckweed for the production of the biofuels, especially starch enrichment in duckweed plants. There are mainly two processes affecting the accumulation of starch in duckweed biomass: photosynthesis for starch generation and metabolism-related starch consumption. The cost of stimulating photosynthesis is relatively high based on current technologies. Considerable research efforts have been made to inhibit starch degradation. Future research need in this area includes duckweed selection, optimisation of duckweed biomass production, enhancement of starch accumulation in duckweeds and use of duckweeds for production of various biofuels. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  16. Adult congenital heart disease: a growing epidemic.

    Science.gov (United States)

    Ávila, Pablo; Mercier, Lise-Andrée; Dore, Annie; Marcotte, François; Mongeon, François-Pierre; Ibrahim, Reda; Asgar, Anita; Miro, Joaquim; Andelfinger, Gregor; Mondésert, Blandine; de Guise, Pierre; Poirier, Nancy; Khairy, Paul

    2014-12-01

    Medical and surgical breakthroughs in the care of children born with heart defects have generated a growing population of adult survivors and spawned a new subspecialty of cardiology: adult congenital heart disease. The prevalence of adult congenital heart disease is escalating at a rampant rate, outpacing the relatively static prevalence of pediatric congenital heart disease, because adults now surpass children in numbers by a ratio of 2:1. As such, congenital heart disease can no longer be considered primarily a pediatric specialty. Most congenital heart defects are not curable and require lifelong specialized care. Health care systems worldwide are challenged to meet the unique needs of this increasingly complex patient population, including the development of supraregional centres of excellence to provide comprehensive and multidisciplinary specialized care. In this review, we explore the incidence and prevalence of congenital heart disease and their changing patterns, address organization and delivery of care, highlight the importance of appropriate training and dedicated research, summarize the high burden of health care resource utilization, and provide an overview of common issues encountered in adults with congenital heart disease. Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.

  17. Bioaugmentation in growing plants for lunar bases

    Science.gov (United States)

    Zaets, I.; Burlak, O.; Rogutskyy, I.; Vasilenko, A.; Mytrokhyn, O.; Lukashov, D.; Foing, B.; Kozyrovska, N.

    2011-03-01

    Microorganisms may be a key element in a precursory scenario of growing pioneer plants for extraterrestrial exploration. They can be used for plant inoculation to leach nutritional elements from regolith, to alleviate lunar stressors, as well as to decompose both lunar rocks and the plant straw in order to form a protosoil. Bioleaching capacities of both French marigold (Tagetes patula L.) and the associated bacteria in contact with a lunar rock simulant (terrestrial anorthosite) were examined using the model plant-bacteria microcosms under controlled conditions. Marigold accumulated K, Na, Fe, Zn, Ni, and Cr at higher concentrations in anorthosite compared to the podzol soil. Plants inoculated with the consortium of well-defined species of bacteria accumulated higher levels of K, Mg, and Mn, but lower levels of Ni, Cr, Zn, Na, Ca, Fe, which exist at higher levels in anorthosite. Bacteria also affected the Са/Mg and Fe/Mn ratios in the biomass of marigold grown on anorthosite. Despite their growth retardation, the inoculated plants had 15% higher weight on anorthosite than noninoculated plants. The data suggest that the bacteria supplied basic macro-and microelements to the model plant.

  18. Growing Bacteriophage M13 in Liquid Culture.

    Science.gov (United States)

    Green, Michael R; Sambrook, Joseph

    2017-11-01

    Stocks of bacteriophage M13 are usually grown in liquid culture. The infected bacteria do not lyse but, instead, grow at a slower than normal rate to form a dilute suspension. The inoculum of bacteriophage is almost always a freshly picked plaque or a suspension of bacteriophage particles obtained from a single plaque, as described here. Infected cells contain up to 200 copies of double-stranded, replicative-form DNA and extrude several hundred bacteriophage particles per generation. Thus, a 1-mL culture of infected cells can produce enough double-stranded viral DNA (1-2 mg) for restriction mapping and recovery of cloned DNA inserts and sufficient single-stranded DNA (∼5-10 mg) for site-directed mutagenesis, DNA sequencing, or synthesis of radiolabeled probes. The titer of bacteriophages in the supernatant from infected cells is so high (∼10(12) pfu/mL) that a small aliquot serves as a permanent stock of the starting plaque. © 2017 Cold Spring Harbor Laboratory Press.

  19. The Growing Regulation of Conversion Therapy.

    Science.gov (United States)

    Drescher, Jack; Schwartz, Alan; Casoy, Flávio; McIntosh, Christopher A; Hurley, Brian; Ashley, Kenneth; Barber, Mary; Goldenberg, David; Herbert, Sarah E; Lothwell, Lorraine E; Mattson, Marlin R; McAfee, Scot G; Pula, Jack; Rosario, Vernon; Tompkins, D Andrew

    2016-01-01

    Conversion therapies are any treatments, including individual talk therapy, behavioral (e.g. aversive stimuli), group therapy or milieu (e.g. "retreats or inpatient treatments" relying on all of the above methods) treatments, which attempt to change an individual's sexual orientation from homosexual to heterosexual. However these practices have been repudiated by major mental health organizations because of increasing evidence that they are ineffective and may cause harm to patients and their families who fail to change. At present, California, New Jersey, Oregon, Illinois, Washington, DC, and the Canadian Province of Ontario have passed legislation banning conversion therapy for minors and an increasing number of US States are considering similar bans. In April 2015, the Obama administration also called for a ban on conversion therapies for minors. The growing trend toward banning conversion therapies creates challenges for licensing boards and ethics committees, most of which are unfamiliar with the issues raised by complaints against conversion therapists. This paper reviews the history of conversion therapy practices as well as clinical, ethical and research issues they raise. With this information, state licensing boards, ethics committees and other regulatory bodies will be better able to adjudicate complaints from members of the public who have been exposed to conversion therapies.

  20. Gasification research on wood grow project

    Energy Technology Data Exchange (ETDEWEB)

    Flanigan, V J

    1981-01-09

    The GROW (Gasification Research on Wood) project consists of a research project on thermochemical degradation of wood particles (sawdust or hammermilled wood) on a pilot plant scale and utilizes a 100 cm (40 in.) diameter fluidized sand bed reactor at capacities of up to 1000 Kg/Hr (2200 lb/hr). Supplementary facilities include wood preparation and air conveying, a wood feed bin, feed and transfer screws, an air compressor with storage and filter tanks, an electrical preheater, a propane-fired preheater, a cyclone separator removing solids from product gas, a water scrubber to cool and clean product gas, a scrubber wate settling tank, a scrubber water cooler, a knockout drum, a demister to be installed in the future, a recycle compressor for recirculation, a recycle gas storage tank, a flare and stack with air blower to dispose of the gas, 2 CO/sub 2/ stripper columns to be installed in the future to remove CO/sub 2/ by caustic adsorption, caustic tanks, and the necessary piping, pumps, sampling, and measurement facilities. A brief report of progress on the project is given, followed by the safety implementation plan and operating, maintenance, and safety procedures. (MHR)

  1. Turkey opens electricity markets as demand grows

    Energy Technology Data Exchange (ETDEWEB)

    McKeigue, J.; Da Cunha, A.; Severino, D. [Global Business Reports (United States)

    2009-06-15

    Turkey's growing power market has attracted investors and project developers for over a decade, yet their plans have been dashed by unexpected political or financial crises or, worse, obstructed by a lengthy bureaucratic approval process. Now, with a more transparent retail electricity market, government regulators and investors are bullish on Turkey. Is Turkey ready to turn the power on? This report closely examine Turkey's plans to create a power infrastructure capable of providing the reliable electricity supplies necessary for sustained economic growth. It was compiled with on-the-ground research and extensive interview with key industrial and political figures. Today, hard coal and lignite account for 21% of Turkey's electricity generation and gas-fired plants account for 50%. The Alfin Elbistan-B lignite-fired plant has attracted criticism for its lack of desulfurization units and ash dam facilities that have tarnished the industry's image. A 1,100 MW hard-coal fired plant using supercritical technology is under construction. 9 figs., 1 tab.

  2. 7 CFR 916.15 - Marketing season.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Marketing season. 916.15 Section 916.15 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Regulating Handling Definitions § 916.15 Marketing season. Marketing season means the period beginning on...

  3. Effects of fire frequency and season on resprouting of woody plants in southeastern US pine-grassland communities.

    Science.gov (United States)

    Robertson, Kevin M; Hmielowski, Tracy L

    2014-03-01

    Past studies suggest that rates of woody plant resprouting following a "topkilling" disturbance relate to timing of disturbance because of temporal patterns of below-ground carbohydrate storage. Accordingly, we hypothesized that fire-return interval (1 or 2 years) and season of burn (late dormant or early growing season) would influence the change in resprout growth rate from one fire-free interval to the next (Δ growth rate) for broadleaf woody plants in a pine-grassland in Georgia, USA. Resprout growth rate during one fire-free interval strongly predicted growth rate during the following fire-free interval, presumably reflecting root biomass. Length of fire-free interval did not have a significant effect on mean Δ growth rate. Plants burned in the late dormant season (February-March) had a greater positive Δ growth rate than those burned in the early growing season (April-June), consistent with the presumption that root carbohydrates are depleted and thus limiting during spring growth. Plants with resprout growth rates above a certain level had zero or negative Δ growth rates, indicating an equilibrium of maximum resprout size under a given fire-return interval. This equilibrium, as well as relatively reduced resprout growth rate following growing season fires, provide insight into how historic lightning-initiated fires in the early growing season limited woody plant dominance and maintained the herb-dominated structure of pine-grassland communities. Results also indicate tradeoffs between applying prescribed fire at 1- versus 2-year intervals and in the dormant versus growing seasons with the goal of limiting woody vegetation.

  4. Simulated sensitivity of African terrestrial ecosystem photosynthesis to rainfall frequency, intensity, and rainy season length

    Science.gov (United States)

    Guan, Kaiyu; Good, Stephen P.; Caylor, Kelly K.; Medvigy, David; Pan, Ming; Wood, Eric F.; Sato, Hisashi; Biasutti, Michela; Chen, Min; Ahlström, Anders; Xu, Xiangtao

    2018-02-01

    There is growing evidence of ongoing changes in the statistics of intra-seasonal rainfall variability over large parts of the world. Changes in annual total rainfall may arise from shifts, either singly or in a combination, of distinctive intra-seasonal characteristics –i.e. rainfall frequency, rainfall intensity, and rainfall seasonality. Understanding how various ecosystems respond to the changes in intra-seasonal rainfall characteristics is critical for predictions of future biome shifts and ecosystem services under climate change, especially for arid and semi-arid ecosystems. Here, we use an advanced dynamic vegetation model (SEIB-DGVM) coupled with a stochastic rainfall/weather simulator to answer the following question: how does the productivity of ecosystems respond to a given percentage change in the total seasonal rainfall that is realized by varying only one of the three rainfall characteristics (rainfall frequency, intensity, and rainy season length)? We conducted ensemble simulations for continental Africa for a realistic range of changes (‑20% ~ +20%) in total rainfall amount. We find that the simulated ecosystem productivity (measured by gross primary production, GPP) shows distinctive responses to the intra-seasonal rainfall characteristics. Specifically, increase in rainfall frequency can lead to 28% more GPP increase than the same percentage increase in rainfall intensity; in tropical woodlands, GPP sensitivity to changes in rainy season length is ~4 times larger than to the same percentage changes in rainfall frequency or intensity. In contrast, shifts in the simulated biome distribution are much less sensitive to intra-seasonal rainfall characteristics than they are to total rainfall amount. Our results reveal three major distinctive productivity responses to seasonal rainfall variability—‘chronic water stress’, ‘acute water stress’ and ‘minimum water stress’ - which are respectively associated with three broad spatial patterns

  5. Temporal and spatial variability of frost-free seasons in the Great Lakes region of the United States

    Science.gov (United States)

    Lejiang Yu; Shiyuan Zhong; Xindi Bian; Warren E. Heilman; Jeffrey A. Andresen

    2014-01-01

    The frequency and timing of frost events and the length of the growing season are critical limiting factors in many human and natural ecosystems. This study investigates the temporal and spatial variability of the date of last spring frost (LSF), the date of first fall frost (FFF), and the length of the frost-free season (FFS) in the Great Lakes region of the United...

  6. Seasonal changes in the understorey biomass of an oak-hornbeam forest Galio sylvatici-Carpinetum betuli

    OpenAIRE

    Andrzej M. Jagodziński; Pietrusiak, Katarzyna; Rawlik, Mateusz; Janyszek, Sławomir

    2013-01-01

    We studied seasonal changes in the understorey biomass of an oak-hornbeam forest association Galio sylvatici-Carpinetum betuli. Samples were collected weekly during the most dynamic period of herbaceous layer development (April–May 2010), and every two weeks for the remainder of the growing season (June-October). Samples were collected from 10 randomly selected localities of 0.36 m2 within the plant community. The plants harvested were separated by species, then oven-dried and weighe...

  7. Antimicrobial susceptibility testing in biofilm‐growing bacteria

    National Research Council Canada - National Science Library

    Macià, M. D; Rojo‐Molinero, E; Oliver, A

    2014-01-01

    .... The lack of correlation between conventional susceptibility test results and therapeutic success in chronic infections is probably a consequence of the use of planktonically growing instead of biofilm‐growing bacteria...

  8. Proxy of monsoon seasonality in carbon isotopes from paleosols of the southern Chinese Loess Plateau

    Science.gov (United States)

    Wang, Hong; Follmer, Leon R.

    1998-11-01

    Soil organic matter (SOM) and soil carbonate (SC) are common constituents in soils and are directly related to plant growth. SOM accumulates gradually from the decomposition of plant material over time, whereas SC formation is biased to dry-season soil-dissolved CO2 that derives from plant respiration during a drying phase of the growing season. In some mixed C3-C4 environments, the peak of C3 and C4 plant metabolism differs seasonally, and the carbon source that contributes to the SOM and SC can be different. Consequently, δ13SOM values reflect an annual average of the floral biomass, but δ13SC values reflect a seasonal aspect of the plant community. The relationship between δ13CSC and δ13CSOM is mainly controlled by how different the seasonal conditions are. Our results suggest that the relationship is a seasonal proxy that can be used to differentiate the seasonality effects of Indian, East Asian, and Siberian monsoons on the Chinese Loess Plateau during the last interglacial-glacial cycle.

  9. Proxy of monsoon seasonality in carbon isotopes from paleosols of the southern Chinese Loess Plateau

    Science.gov (United States)

    Wang, Hongfang; Follmer, L.R.

    1998-01-01

    Soil organic matter (SOM) and soil carbonate (SC) are common constituents in soils and are directly related to plant growth. SOM accumulates gradually from the decomposition of plant material over time, whereas SC formation is biased to dry-season soil-dissolved CO2 that derives from plant respiration during a drying phase of the growing season. In some mixed C3-C4 environments, the peak of C3 and C4 plant metabolism differs seasonally, and the carbon source that contributes to the SOM and SC can be different. Consequently, ??13C(SOM) values reflect an annual average of the floral biomass, but ??13C(SC) values reflect a seasonal aspect of the plant community. The relationship between ??13C(SC) and ??13C(SOM) is mainly controlled by how different the seasonal conditions are. Our results suggest that the relationship is a seasonal proxy that can be used to differentiate the seasonality effects of Indian, East Asian, and Siberian monsoons on the Chinese Loess Plateau during the last interglacial-glacial cycle.

  10. Growing skull fracture stages and treatment strategy.

    Science.gov (United States)

    Liu, Xue-Song; You, Chao; Lu, Ma; Liu, Jia-Gang

    2012-06-01

    A growing skull fracture (GSF) is a rare but significant late complication of skull fractures, usually occurring during infancy and early childhood. Delayed diagnosis and improper treatment could exacerbate this disease. The aim of this study was to introduce a new hypothesis about, describe the stages of, and discuss the treatment strategy for GSF. The authors performed a retrospective review of 27 patients with GSF, who were grouped according to 3 different GSF stages. Over a period of 20 years, 27 patients with GSF (16 males and 11 females) were treated in the authors' department. The mean follow-up period was 26.5 months. Six patients were in the prephase of GSF (Stage 1), 10 patients in the early phase (Stage 2), and 11 in the late phase (Stage 3). All patients underwent duraplasty. All 6 patients at Stage 1 and 5 patients at Stage 2 underwent craniotomy without cranioplasty. Five patients at Stage 2 and all of the patients at Stage 3 underwent cranioplasty with autologous bone and alloplastic materials, respectively. Among all patients, 5 underwent ventriculoperitoneal shunt placement. Symptoms in all patients at Stages 1 and 2 were alleviated or disappeared, and the cranial bones developed without deformity during follow-up. Among patients with Stage 3 GSF, no obvious improvement in neurological deficits was observed. Three patients underwent additional operations because of cranial deformation or infection. The authors identify the stages of GSF according to a new hypothesis. They conclude that accurately diagnosing and treating GSF during Stages 1 and 2 leads to a better prognosis.

  11. [Lung cancer and COPD - growing clinical problem].

    Science.gov (United States)

    Tyl, Michal; Domagała-Kulawik, Joanna

    2017-07-21

    A spread of the addiction of tobacco smoking is valued on near 1 billion of people in the world, that involves growing number of morbidity and mortality by the reason of smoke related diseases. Lung cancer and chronic obstructive pulmonary disease (COPD) are the most serious and incurable diseases which are leading to a permanent disability as well as to premature death. There are factors that naturally increase the vulnerability of an individual on the coincidence of above disorders, such as pathophysiological conditions, systemic inflammation, bronchitis, emphysema, respiratory obstructive disease and precise genetic predispositions for COPD and lung cancer. The harmful substances of the tobacco smoke are the causes of the development of diseases outside the group of respiratory disorders which affects the greater scope of comorbidity among this patient group in comparison to the normal population. The similarity of the clinical picture of lung cancer and COPD may cause numerous problems for a proper and prompt diagnosis and the implementation of the appropriate treatment. On the other hand, it is evident that the patients with COPD are carefully examined and often diagnosed with cancer while those who already suffer from cancer and undertake additional function testing are in 40-50% diagnosed with COPD. The coexistance of these two diseases influences the therapeutic procedure: COPD limits the possibilities of a radical lung cancer treatment which is determined by the general health condition and the respiratory system insufficiency as far as COPD patients are concerned. The knowledge of common pathogenesis both of cancer and COPD and the mutual relations between them shall positively affect the diagnostic and therapeutic process in the high-risk patient groups.

  12. Where is my wine from? - A global exposure database for wineries and wine growing regions

    Science.gov (United States)

    Daniell, James E.; Daniell, Trevor M.; Wenzel, Friedemann; Schaefer, Andreas M.; Daniell, Katherine A.; Burford, Robert

    2017-04-01

    The production of a global winery and wine database is a great undertaking and was required for the evaluation of winery risk in various locations (see NH ECS Lecture MH42/NH). The following study detailed a country wide study of wineries in 15 major wine growing locations globally in order to evaluate the ability of using existing information to detail the risk properties of the wine growing regions. In addition parameters such as the winery types, grape types, slopes, buildings, hazard properties and land use were surveyed. In terms of the winery locations, point-based as well as spatial land-use disaggregated polygons were used. For grape production, national and winery region data was aggregated from existing sources in each country. The value and type were assessed. For the slopes, global and regional DEMs such as ALOS, SRTM and EU-DEM were examined and converted within GIS envrionments. Building level information was often difficult to establish where OSM data was lacking (OpenStreetMap). Hazard parameters such as earthquake ground motion probability, weather, wind speeds, changing grape types, seasonality as well as the variability within seasons were collected with the variability being key to showing an increase or decrease in quality. Tools that were used can be applied to other exposure datasets; and shows a methodology to aggregate exposure information with respect to industries as well as other sectors using open data.

  13. FORWINE - Statistical Downscaling of Seasonal forecasts for wine

    Science.gov (United States)

    Cardoso, Rita M.; Soares, Pedro M. M.; Miranda, Pedro M. A.

    2016-04-01

    The most renowned viticulture regions in the Iberian Peninsula have a long standing tradition in winemaking and are considered world-class grapevine (Vitis Vinifera L.) producing regions. Portugal is the 11th wine producer in the world, with internationally acclaimed wines, such as Port wine, and vineyards across the whole territory. Climate is widely acknowledged of one of the most important factors for grapevine development and growth (Fraga et al. 2014a and b; Jackson et al. 1993; Keller 2010). During the growing season (April-October in the Northern Hemisphere) of this perennial and deciduous crop, the climatic conditions are responsible for numerous morphologically and physiological changes. Anomalously low February-March mean temperature, anomalously high May mean temperature and anomalously high March precipitation tend to be favourable to wine production in the Douro Valley. Seasonal forecast of precipitation and temperature tailored to fit critical thresholds, for crucial seasons, can be used to inform management practices (viz. phytosanitary measures, land operations, marketing campaigns) and develop a wine production forecast. Statistical downscaling of precipitation, maximum, minimum temperatures is used to model wine production following Santos et al. (2013) and to calculate bioclimatic indices. The skill of the ensemble forecast is evaluated through anomaly correlation, ROC area, spread-error ratio and CRPS

  14. [Studies on the alkaloids of Senecio scandens growing in Guangdong].

    Science.gov (United States)

    Guo, Xiao-Fang; Liu, Meng-Hua; Peng, Wei; Wang, Yong-Gang; Yang, Cui-Ping; Su, Wei-Wei

    2011-05-01

    To study alkaloids of Senecio scandens growing in Guangdong. The rapid resolution liquid chromatography-electrospray ionization mass spectrometry (RRLC-ESI-MS/MS) was used to analyse alkaloids of Senecio scandens growing in Guangdong, and senkirkine was isolated and purified by silica gel column chromatography. Four alkaloids were identified as senkirkine, dehydrosenkirkine, monocrotaline and adonifoline, and senkirkine was firstly isolated from Senecio scandens growing in Guangdong. Senkirkine is the main component of Senecio scandens growing in Guangdong.

  15. Effects of herbaceous and woody plant control on Pinus palustris growth and foliar nutrients through six growing seasons

    Science.gov (United States)

    James D. Haywood

    2005-01-01

    To determine if either herbaceous or woody plants are more competitive with longleaf pine (Pinuspalustris P. Mill.) seedlings, two vegetation management treatments-herbaceous plant control (HPC, No or Yes) and woody plant control (WPC, No or Yes) were applied in newly established longleaf pine plantings in a randomized complete block 2 x 2 factorial...

  16. Trace gas fluxes from intensively managed rice and soybean fields across three growing seasons in the Brazilian Amazon

    Science.gov (United States)

    R.C. Oliveira Junior; Michael Keller; P. Crill; T. Beldini; J. Van Haren; P. Camargo

    2015-01-01

    The emission of gases that may potentially intensify the greenhouse effect has received special attention due to their ability to raise global temperatures and possibly modify conditions for life on earth. The objectives of this study were the quantification of trace gas flux (N2O, CO2 and CH4) in soils of the lower Amazon basin that are planted with rice and soybean,...

  17. Radionuclide concentrations in/on vegetation at radioactive-waste disposal Area G during the 1995 growing season. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Fresquez, P.R.; Vold, E.L.; Naranjo, L. Jr.

    1996-03-01

    Overstory (pinon pine) and understory (grass and forb) vegetation were collected within and around selected points at Area G--a low- level radioactive solid-waste disposal facility at Los Alamos National Laboratory--for the analysis of tritium ({sup 3}H), strontium ({sup 90}Sr), plutonium ({sup 238}Pu and {sup 239}Pu), cesium ({sup 137}Cs), and total uranium. Also, heavy metals (Ag, As, Ba, Be, Cd, Cr, Hg, Ni, Pb, Sb, Se, and Tl) in/on vegetation were determined. In general, most (unwashed) vegetation collected within and around Area G contained {sup 3}H, uranium, {sup 238}Pu, and {sup 239}Pu in higher concentrations than vegetation collected from background areas. Tritium, in particular, was detected as high as 7300 pCi mL{sup -1} in understory vegetation collected from the west side of the transuranic (TRU) pads. The south and west ends of the tritium shaft field also contained elevated levels of {sup 3}H in overstory, and especially in understory vegetation, as compared to background; this suggests that {sup 3}H may be migrating from this waste repository through surface and subsurface pathways. Also, understory vegetation collected north of the TRU pads (adjacent to the fence line of Area G) contained the highest values of {sup 238}Pu and {sup 239}Pu as compared to background, and may be a result of surface holding, storage, and/or disposal activities.

  18. Influence of tillage practices on soil biologically active organic matter content over a growing season under semiarid Mediterranean climate

    Directory of Open Access Journals (Sweden)

    D. Martín-Lammerding

    2013-02-01

    Full Text Available In semiarid areas, traditional, intensive tillage has led to the depletion of soil organic matter, which has resulted in reduced soil fertility. The aim of the present work was to evaluate the effects of different soil management systems, practised over 12 years, on soil organic carbon (SOC, nitrogen (SN and biologically active organic matter (particulate organic matter [POM]; potentially mineralisable nitrogen [PMN]; microbial biomass [MB]. A Mediterranean Alfisol, located in central Spain, was managed using combinations of conventional tillage (CT, minimum tillage (MT or no-tillage (NT, plus a cropping background of either continuous wheat (WW or a fallow/wheat/pea/barley rotation (FW. Soil was sampled at two depths on four occasions during 2006-2007. The results showed the sampling date and the cropping background to significantly affect the SOC (p<0.0057 and p<0.0001 respectively. Tillage practice, however, had no effect on SOC or SN. The C-and N-POM contents were significantly influenced by the date, tillage and rotation. These variables were significantly higher under NT than CT and under WW than FW. The PMN was influenced by date, tillage and rotation, while C-MB was significantly affected by tillage (p< 0.0063, but not by rotation. The NT plots accumulated 66% C-POM, 60% N-POM, 39% PMN and 84% C-MB more than the CT plots. After more than 12 years, the benefits of conservation practices were found in the considered soil properties, mainly under no tillage. In order to obtain a consistent data set to predict soil biological status, it is necessary further study over time.

  19. Assessment of Ammonia Volatilization Losses and Nitrogen Utilization during the Rice Growing Season in Alkaline Salt-Affected Soils

    Directory of Open Access Journals (Sweden)

    Yangyang Li

    2017-01-01

    Full Text Available The objectives of this study were to evaluate the effects of different fertilizer types and application rates on ammonia volatilization loss and to explore nitrogen distribution and nitrogen use efficiency using the 15N isotope tracing technique in different alkaline salt-affected conditions in the Songnen Plain, Northeast China. The results showed a decreasing trend in ammonia volatilization loss from ammonium nitrate and ammonium sulfate, but not that from urea, as the electrical conductivity gradient increased, whereas the reverse trend was found as the pH gradient increased. Ammonia volatilization loss increased in moderately salt-affected soil compared with that in slightly salt-affected soil, particularly during the tillering stage, regardless of the N fertilizer rate. The percentage of N absorbed by rice plants increased from urea but decreased from the soil as the amount of nitrogen was increased. Interestingly, the N retention rate in soil decreased and rice grain yield and nitrogen agronomic efficiency increased as the amount of nitrogen increased in both salt-affected soil conditions. The nitrogen application amount of highest N physiological efficiency was 225 kg·N/ha. Considering high rice production and a minimal environmental threat, we should fully consider controlling ammonia volatilization losses by adjusting the fertilizer type and the crop stage when the fertilizer is applied.

  20. Effect of directed-spray glyphosate applications on survival and growth of planted oaks after three growing seasons

    Science.gov (United States)

    Andrew B. Self; Andrew W. Ezell; Josh L. Moree; Rory O. Thornton

    2013-01-01

    Thousands of acres of oak (Quercus spp.) plantations are established across the South annually. Survival and growth of these plantings have been less than desirable. Several techniques have been utilized in attempts to achieve improved success in these areas. One such technique that has been recommended is the application of directed-spray herbicide...

  1. European scale modeling of sulfur, oxidized nitrogen and photochemical oxidants. Model development and evaluation for the 1994 growing season

    Energy Technology Data Exchange (ETDEWEB)

    Langner, J.; Bergstroem, R. [Swedish Meteorological and Hydrological Inst., Norrkoeping (Sweden); Pleijel, K. [Swedish Environmental Research Inst., Goeteborg (Sweden)

    1998-09-01

    A chemical mechanism, including the relevant reactions leading to the production of ozone and other photochemical oxidants, has been implemented in the MATCH regional tracer transport/chemistry/deposition model. The aim has been to develop a model platform that can be used as a basis for a range of regional scale studies involving atmospheric chemistry, including assessment of the importance of different sources of pollutants to the levels of photochemical oxidants and air pollutant forecasting. Meteorological input data to the model were taken from archived output from the operational version of HIRLAM at SMHI. Evaluation of model calculations over Europe for a six month period in 1994 for a range of chemical components show good results considering known sources of error and uncertainties in input data and model formulation. With limited further work the system is sufficiently good to be applied for scenario studies and for regional scale air pollutant forecasts 42 refs, 24 figs, 17 tabs

  2. Radionuclide concentrations in soils and vegetation at radioactive-waste disposal Area G during the 1996 growing season. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Fresquez, P.R.; Vold, E.L.; Naranjo, L. Jr.

    1997-07-01

    Soil and overstory and understory vegetation (washed and unwashed) collected at eight locations within and around Area G--a low-level radioactive solid-waste disposal facility at Los Alamos National laboratory--were analyzed for {sup 3}H, {sup 90}Sr, {sup 238}Pu, {sup 239}Pu, {sup 137}Cs, {sup 234}U, {sup 235}U, {sup 238}U, {sup tot}U, {sup 228}Ac, {sup 214}Bi, {sup 60}Co, {sup 40}K, {sup 54}Mn, {sup 22}Na, {sup 214}Pb, and {sup 208}Tl. Also, heavy metals (Ag, As, Ba, Be, Cd, Cr, Hg, Ni, Pb, Sb, Se, and Tl) in soil and vegetation were determined. In general, most radionuclide concentrations, with the exception of {sup 3}H and {sup 239}Pu, in soils and washed and unwashed overstory and understory vegetation collected from within and around Area G were within upper limit background concentrations. Tritium was detected as high as 14,744 pCi mL{sup {minus}1} in understory vegetation collected from transuranic (TRU) waste pad {number_sign}4, and the TRU waste pad area contained the highest levels of {sup 239}Pu in soils and in understory vegetation as compared to other areas at Area G.

  3. Experimental branch cooling increases foliar sugar and anthocyanin concentrations in sugar maple at the end of the growing season

    Science.gov (United States)

    Paul G. Schaberg; Paula F. Murakami; John R. Butnor; Gary J. Hawley

    2017-01-01

    Autumnal leaf anthocyanin expression is enhanced following exposure to a variety of environmental stresses and may represent an adaptive benefit of protecting leaves from those stresses, thereby allowing for prolonged sugar and nutrient resorption. Past work has shown that experimentally induced sugar accumulations following branch girdling triggers anthocyanin...

  4. Influence of herbicides and felling, fertilization, and prescribed fire on longleaf pine establishment and growth through six growing seasons

    Science.gov (United States)

    James D. Haywood

    2006-01-01

    Recovery of longleaf pine (Pinus palutris. Mill.) is necessary to arrest the decline of many associated plants and animals, and the establishment of longleaf pine on much of its original range requires artificial regeneration and diligence. In central Louisiana, USA, two fertilization levels (No [NF] or Yes [F-36 kg/ha N and 40 kg/ha PI) in...

  5. The spring and autumn phenophases of the broadleaves trees indicate the extension of growing season in the boreal forest environment

    Science.gov (United States)

    Kubin, Eero; Poikolainen, Jarmo; Karhu, Jouni; Tolvanen, Anne

    2014-05-01

    The long-term historical data since 1752 shows an advancement in the timing of flowering by five days per century in Prunus padus. The onset of flowering in Sorbus aucuparia has become correspondingly earlier in Finland at the rate of three days per century. The results of the Finnish National Phenological Network fit well in the historical data. The Finnish National Phenological Network was established in 1996 in collaboration with research institutes and universities. The phenomena being studied by trained observers using a standardized manner are flowering and flushing of trees, yellowing and shedding of leaves, height growth and flowering of conifers, flowering of Vaccinium vitis-idaea and Vaccinium myrtillus and the ripening of berries. The monitoring covers eight tree species: Betula pubescens, Betula pendula, Pinus silvestris, Picea abies, Populus tremula, Juniperus communis, Prunus padus and Sorbus aucuparia. The observations are made repeatedly of the same tree individuals at least twice per week. The real time results are visible in the form of animations and charts (http://www.metla.fi/metinfo/fenologia/index-en.htm). The green wave from south to north and yellowishing from north to south will be presented in the conference. The onset of downy birch leaves occurred in northernmost Lapland about a month later compared with southern Finland and began to turn yellow already at the beginning of September. The onset and progress of growth are primarily dependeing on air temperature. The results of the network confirm that spring phenophases have especially in northern Finland advanced with respect to climatic conditions. For autumn phenopases we found in several sites delaying trend, but not as strong as in spring phenopases. Downy birch, Betula pubescens, has been found to leaf on average when the effective temperature sum has reached 54 dd. in the southern part of the country, but in the north only 38 dd. is needed. The less temperature sum requirement within the boreal zone in the north compared with south is not reported earlier. In the north less temperature sum was also needed for the flowering of bird cherry. Phenological monitoring by using field observations is nowadays more important than ever especially in arctic and boreal regions, where spring temperatures are elevated. Compilation and documentation of observations on plant phenophases play a key role in working out the rate of global climate change. There occurs however great variation of phenophases between the years and sites causing uncertainty for the use of data. The observation term of the Finnish National Phenological Network, seventeen years, starts to be long enough for recent responses, but it is still too short to tell whether the advancement of spring or delaying autumn is a constant phenomenon or a consequence of normal climatic variability. The timing of especially autumn phenophases and onset of leafing with respect to temperature sum will be discussed in the conference.

  6. Global-scale pattern of peatland Sphagnum growth driven by photosynthetically active radiation and growing season length

    OpenAIRE

    Z. Yu; A. V. Gallego-Sala; J. Loisel

    2012-01-01

    High-latitude peatlands contain about one third of the world's soil organic carbon, most of which is derived from partly decomposed Sphagnum (peat moss) plants. We conducted a meta-analysis based on a global data set of Sphagnum growth measurements collected from published literature to investigate the effects of bioclimatic variables on Sphagnum growth. Analysis of variance and general linear models were used to relate Sphagnum magellanicum and S. fuscum growth rates to photosynthetically ac...

  7. Global-scale pattern of peatland Sphagnum growth driven by photosynthetically active radiation and growing season length

    OpenAIRE

    Z. Yu; A. V. Gallego-Sala; J. Loisel

    2012-01-01

    High-latitude peatlands contain about one third of the world's soil organic carbon, most of which is derived from partly decomposed Sphagnum (peat moss) plants. We conducted a meta-analysis based on a global dataset of Sphagnum growth measurements collected from published literature to investigate the effects of bioclimatic variables on Sphagnum growth. Analysis of variance and general linear models were used to relate Sphagnum magellanicum and S. fuscum growth rates to photosynthetically...

  8. Irrigation strategies that use cutout for optimum boll maturation and yield where growing season duration is limited

    Science.gov (United States)

    Irrigation water availability is decreasing due to declining water sources and greater competition. Many producers must now comply with annual pumping restrictions that may limit overall productivity of crops like corn (Zea mays L.). Cotton [Gossypium hirsutum (L.)] water demand is less than corn, b...

  9. Relationships Among Canopy Scale Energy Fluxes and Isoprene Flux Using Eddy Covariance Measurements Over Multiple Growing Seasons

    Science.gov (United States)

    Pressley, S. N.; Lamb, B. K.; Westberg, H.

    2003-12-01

    Isoprene is one of the most abundant biogenic trace gases in the troposphere. Biogenic trace gases affect tropospheric chemistry by forming gaseous and particulate secondary products in conjunction with anthropogenic emissions that contribute to the degradation of air quality. Our understanding of the impact isoprene has on tropospheric photochemistry is hampered by our limited knowledge of the biosphere-atmosphere exchange process, and thus the inability to accurately quantify the biogenic emission inventory. Isoprene emissions are regulated by many environmental variables; the most important variables are known to be temperature and light. The research summarized here seeks to improve our understanding of biogenic emissions from forest ecosystems as a basis for advancing our ability to describe the role of biogenics in regional and global atmospheric chemical cycles. Biogenic emission models, such as BEIS (Biogenic Emission Inventory System) rely on above canopy environmental parameters and below canopy scaling factors to estimate canopy scale biogenic hydrocarbon fluxes. This type of model can predict biogenic emissions well, however, the required input is extensive, and for regional applications, it can be cumbersome. Based on the assumption that isoprene emission rates are enzymatic (a function of temperature, light, and historical temperature), we propose that sensible heat flux can be a surrogate for above canopy temperature and light when estimating isoprene fluxes at the canopy scale. In addition, sensible heat flux may be a better indicator of the canopy interaction with incoming energy, as opposed to scaling above canopy parameters. Thus, the use of surface energy fluxes such as sensible heat flux is an attempt to combine the biological (enzymatic) and meteorological processes that affect the biosphere-atmosphere exchange of isoprene. Since surface energy budgets are an integral part of mesoscale meteorological models, this could potentially be a useful tool for including biogenic emissions into regional atmospheric models. Long-term measurements of isoprene flux have been collected above a northern hardwood forest at the AmeriFlux site located at the University of Michigan Biological Station (UMBS) as part of the Program for Research on Oxidants: Photochemistry, Emissions, and Transport (PROPHET). Measurements have been made every summer since 1998 using eddy covariance techniques, and the data are now available for determining the relationship between isoprene flux and surface energy fluxes. Using this long-term dataset we hope to improve our understanding of isoprene emissions and, thus, improve our ability to include isoprene emissions in regional and global atmospheric chemistry models.

  10. A growing danger: the risks posed by marihuana grow-ops

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, F. [Canadian Electricity Association (Canada)

    2005-02-01

    The proliferation of sophisticated illegal indoor multi-plant marihuana cultivation operations is discussed, focusing primarily on public health and safety issues. Public health issues arise from the high level of molds and pollens caused by high humidity, which can cause asthma, respiratory conditions and allergies, particularly among children, and the likelihood of deadly levels of carbon monoxide build-up resulting from faulty rerouting of the residence's ventilation system. Safety issues discussed are: fires and electrocutions associated with the use of electrical diversions or bipasses to circumvent utility meters, the chemical and electrical hazards involved in investigating and dismantling growing operations, the significant dangers to utility crews who must repair illegal electrical bypasses, injuries by the booby-traps planted to protect the operation from other criminals or law enforcement agents, and the physical danger from the violence, including homicide and assaults, carried out by operators to exert control over production and distribution. Although in general, there is a relaxed attitude towards marihuana use in Canada. there is growing evidence of increasing public concern over large-scale growing operations. Nevertheless, to date operators of grow-ops have been dealt with lightly by the justice system. For example, in British Columbia 11,733 cases have come to the attention of police during the 1997 to 2000 period. Of these about half were dealt with informally (i.e. 'no case' seizures) and 2,255 cases led to at least one offender being convicted. The majority of convictions did not result in custodial dispositions. Only 18 per cent of the cases resulted in prison sentences, the average term being only 4.5 months.

  11. Seasonal Variation of Acute Urolithiasis

    Directory of Open Access Journals (Sweden)

    Albert Tiu

    2010-12-01

    Full Text Available BackgroundUrolithiasis is a common condition. It often affects patients in the prime of life causing significant burden to the society. In our study we are interested in determining whether seasonal variation is a risk factor of acute urolithiasis. Method A retrospective study was performed at a tertiary hospital in Canberra, ACT, Australia. Data pertaining to patient demographics, history of renal colic and management were extracted from charts over a 10-year period. Climatic data for the Australia Capital Territory during this period was retrieved from the Australian Bureau of Meteorology and correlated to renal colic presentations.ResultsData was obtained for 637 patients all with radiologically confirmed calculi of the urinary tract. The median age at diagnosis was 50 years of age. Overall 37.4% of patients had a previous history of urolithiasis and the male to female ratio was 2.8:1. Presentation was most common in the autumn months (32.8%, with the fewest cases of urolithiasis during the winter months (18.7%. At presentations the majority of the calculi were ≤ 5mm and located within the distal ureter. Conservative treatments were instituted more often when stone size was ≤ 5mm. Proximal ureteric calculi were more likely to be treated with surgical intervention.ConclusionWe demonstrate an association between the presentation of primary urolithiasis and season. A better understanding in the subject may help future health care planning to deal with the seasonal increase in presentations of renal colic to the urology service.

  12. Lighting during grow-out and Salmonella in broiler flocks

    Science.gov (United States)

    Lighting is used during broiler grow-out to modify bird behavior to reach the goals of production. The protocols for lighting intensity vary. In a field project, we evaluated if the lighting protocol impacts the burden of Salmonella in grow-out broiler flocks. Conventional grow-out flocks reared ...

  13. WSGB: A Web Service-Based Growing Book

    Science.gov (United States)

    Dow, C. R.; Huang, L. H.; Chen, K. H.; Chiu, J. C.; Lin, C. M.

    2006-01-01

    Growing Book refers to an electronic textbook that is co-developed, and has the ability to be constantly maintained, by groups of independent authors, thus creating a rich and ever-growing learning environment that can be conveniently accessible from anywhere. This work designs and implements a Web Service-based Growing Book that has the merits of…

  14. Rainfall variability and seasonality in northern Bangladesh

    Science.gov (United States)

    Bari, Sheikh Hefzul; Hussain, Md. Manjurul; Husna, Noor-E.-Ashmaul

    2017-08-01

    This paper aimed at the analysis of rainfall seasonality and variability for the northern part of South-Asian country, Bangladesh. The coefficient of variability was used to determine the variability of rainfall. While rainfall seasonality index ( SI ) and mean individual seasonality index ( \\overline{SI_i} ) were used to identify seasonal contrast. We also applied Mann-Kendall trend test and sequential Mann-Kendall test to determine the trend in seasonality. The lowest variability was found for monsoon among the four seasons whereas winter has the highest variability. Observed variability has a decreasing tendency from the northwest region towards the northeast region. The mean individual seasonality index (0.815378 to 0.977228) indicates that rainfall in Bangladesh is "markedly seasonal with a long dry season." It was found that the length of the dry period is lower at the northeastern part of northern Bangladesh. Trend analysis results show no significant change in the seasonality of rainfall in this region. Regression analysis of \\overline{SI_i} and SI, and longitude and mean individual seasonality index show a significant linear correlation for this area.

  15. Men's attraction to women's bodies changes seasonally.

    Science.gov (United States)

    Pawlowski, Bogusław; Sorokowski, Piotr

    2008-01-01

    Humans exhibit seasonal variation in hormone levels, behaviour, and perception. Here we show that men's assessments of women's attractiveness change also seasonally. In five seasons (from winter 2004 to winter 2005) 114 heterosexual men were asked to assess the attractiveness of the same stimuli: photos of a female with three different waist-to-hip ratios; photos of female breasts, and photos of average-looking faces of young women. For each season, the scores given to the stimuli of the same category (body shape, breast, and face) were combined. Friedman's test revealed significant changes for body shape and breast attractiveness assessments across the seasons, but no changes for face ratings. The highest scores for attractiveness were given in winter and the lowest in summer. We suggest that the observed seasonality is related to the well-known 'contrast effect'. More frequent exposure to women's bodies in warmer seasons might increase men's attractiveness criteria for women's body shape and breasts.

  16. Warm spring temperatures induce persistent season-long changes in shoot development in grapevines.

    Science.gov (United States)

    Keller, Markus; Tarara, Julie M

    2010-07-01

    The influence of temperature on the timing of budbreak in woody perennials is well known, but its effect on subsequent shoot growth and architecture has received little attention because it is understood that growth is determined by current temperature. Seasonal shoot development of grapevines (Vitis vinifera) was evaluated following differences in temperature near budbreak while minimizing the effects of other microclimatic variables. Dormant buds and emerging shoots of field-grown grapevines were heated above or cooled below the temperature of ambient buds from before budbreak until individual flowers were visible on inflorescences, at which stage the shoots had four to eight unfolded leaves. Multiple treatments were imposed randomly on individual plants and replicated across plants. Shoot growth and development were monitored during two growing seasons. Higher bud temperatures advanced the date of budbreak and accelerated shoot growth and leaf area development. Differences were due to higher rates of shoot elongation, leaf appearance, leaf-area expansion and axillary-bud outgrowth. Although shoots arising from heated buds grew most vigorously, apical dominance in these shoots was reduced, as their axillary buds broke earlier and gave rise to more vigorous lateral shoots. In contrast, axillary-bud outgrowth was minimal on the slow-growing shoots emerging from buds cooled below ambient. Variation in shoot development persisted or increased during the growing season, well after temperature treatments were terminated and despite an imposed soil water deficit. The data indicate that bud-level differences in budbreak temperature may lead to marked differences in shoot growth, shoot architecture and leaf-area development that are maintained or amplified during the growing season. Although growth rates commonly are understood to reflect current temperatures, these results demonstrate a persistent effect of early-season temperatures, which should be considered in future

  17. Tree cover and biomass increase in a southern African savanna despite growing elephant population.

    Science.gov (United States)

    Kalwij, J M; De Boer, W F; Mucina, L; Prins, H H T; Skarpe, C; Winterbach, C

    2010-01-01

    The growing elephant populations in many parts of southern Africa raise concerns of a detrimental loss of trees, resulting in overall reduction of biodiversity and ecosystem functioning. Elephant distribution and density can be steered through artificial waterpoints (AWPs). However, this leaves resident vegetation no relief during dry seasons. We studied how the introduction of eight AWPs in 1996 affected the spatiotemporal tree-structure dynamics in central Chobe National Park, an unfenced savanna area in northern Botswana with a dry-season elephant density of approximately 3.34 individuals per square kilometer. We hypothesized that the impact of these AWPs amplified over time and expanded in space, resulting in a decrease in average tree density, tree height, and canopy volume. We measured height and canopy dimensions of all woody plants around eight artificial and two seasonal waterpoints for 172 plots in 1997, 2000, and 2008. Plots, consisting of 50 x 2 m transects for small trees (0.20-3.00 m tall) nested within 50 x 20 m transects for large trees (> or = 3.0 m tall), were located at 100, 500, 1000, 2000, and 5000 m distance classes. A repeated-measures mixed-effect model showed that tree density, cover, and volume had increased over time throughout the area, caused by a combination of an increase of trees in lower size classes and a decrease in larger size classes. Our results indicate that the decrease of large trees can be attributed to a growing elephant population. Decrease or loss of particular tree size classes may have been caused by a loss of browser-preferred species while facilitating the competitiveness of less-preferred species. In spite of 12 years of artificial water supply and an annual elephant population growth of 6%, we found no evidence that the eight AWPs had a negative effect on tree biomass or tree structure. The decreasing large-tree component could be a remainder of a depleted but currently restoring elephant population.

  18. Seasonal dynamics of mobile carbon supply in Quercus aquifolioides at the upper elevational limit.

    Science.gov (United States)

    Zhu, Wan-Ze; Cao, Min; Wang, San-Gen; Xiao, Wen-Fan; Li, Mai-He

    2012-01-01

    Many studies have tried to explain the physiological mechanisms of the alpine treeline phenomenon, but the debate on the alpine treeline formation remains controversial due to opposite results from different studies. The present study explored the carbon-physiology of an alpine shrub species (Quercus aquifolioides) grown at its upper elevational limit compared to lower elevations, to test whether the elevational limit of alpine shrubs (above sea level (a.s.l.) on Zheduo Mt., SW China. The tissue NSC concentrations along the elevational gradient varied significantly with season, reflecting the season-dependent carbon balance. The NSC levels in tissues were lowest at the beginning of the growing season, indicating that plants used the winter reserve storage for re-growth in the early spring. During the growing season, plants grown at the elevational limit did not show lower NSC concentrations compared to plants at lower elevations, but during the winter season, storage tissues, especially roots, had significantly lower NSC concentrations in plants at the elevational limit compared to lower elevations. The present results suggest the significance of winter reserve in storage tissues, which may determine the winter survival and early-spring re-growth of Q. aquifolioides shrubs at high elevation, leading to the formation of the uppermost distribution limit. This result is consistent with a recent hypothesis for the alpine treeline formation.

  19. The Relationship between an Invasive Shrub and Soil Moisture: Seasonal Interactions and Spatially Covarying Relations

    Directory of Open Access Journals (Sweden)

    Yuhong He

    2014-09-01

    Full Text Available Recent studies indicate that positive relationships between invasive plants and soil can contribute to further plant invasions. However, it remains unclear whether these relations remain unchanged throughout the growing season. In this study, spatial sequences of field observations along a transect were used to reveal seasonal interactions and spatially covarying relations between one common invasive shrub (Tartarian Honeysuckle, Lonicera tatarica and soil moisture in a tall grassland habitat. Statistical analysis over the transect shows that the contrast between soil moisture in shrub and herbaceous patches vary with season and precipitation. Overall, a negatively covarying relationship between shrub and soil moisture (i.e., drier surface soils at shrub microsites exists during the very early growing period (e.g., May, while in summer a positively covarying phenomenon (i.e., wetter soils under shrubs is usually evident, but could be weakened or vanish during long precipitation-free periods. If there is sufficient rainfall, surface soil moisture and leaf area index (LAI often spatially covary with significant spatial oscillations at an invariant scale (which is governed by the shrub spatial pattern and is about 8 m, but their phase relation in space varies with season, consistent with the seasonal variability of the co-varying phenomena between shrub invasion and soil water content. The findings are important for establishing a more complete picture of how shrub invasion affects soil moisture.

  20. On carbon footprints and growing energy use

    Energy Technology Data Exchange (ETDEWEB)

    Oldenburg, C.M.

    2011-06-01

    Could fractional reductions in the carbon footprint of a growing organization lead to a corresponding real reduction in atmospheric CO{sub 2} emissions in the next ten years? Curtis M. Oldenburg, head of the Geologic Carbon Sequestration Program of LBNL’s Earth Sciences Division, considers his own organization's carbon footprint and answers this critical question? In addressing the problem of energy-related greenhouse gas (GHG) emissions and climate change, it is essential that we understand which activities are producing GHGs and the scale of emission for each activity, so that reduction efforts can be efficiently targeted. The GHG emissions to the atmosphere of an individual or group are referred to as the ‘carbon footprint’. This terminology is entirely appropriate, because 85% of the global marketed energy supply comes from carbon-rich fossil fuel sources whose combustion produces CO{sub 2}, the main GHG causing global climate change. Furthermore, the direct relation between CO2 emissions and fossil fuels as they are used today makes energy consumption a useful proxy for carbon footprint. It would seem to be a simple matter to reduce energy consumption across the board, both individually and collectively, to help reduce our carbon footprints and therefore solve the energyclimate crisis. But just how much can we reduce carbon footprints when broader forces, such as growth in energy use, cause the total footprint to simultaneously expand? In this feature, I present a calculation of the carbon footprint of the Earth Sciences Division (ESD), the division in which I work at Lawrence Berkeley National Laboratory (LBNL), and discuss the potential for reducing this carbon footprint. It will be apparent that in terms of potential future carbon footprint reductions under projections of expected growth, ESD may be thought of as a microcosm of the situation of the world as a whole, in which alternatives to the business-as-usual use of fossil fuels are needed if