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991.
Academic, government, and industrial field researchers have generated a significant database of field studies of the volatility
of soil applied fumigants. However, limited work exists in validating physical models against field volatility data sets and
fully exploring the volatility parametric response surface. Field studies quantifying atmospheric flux for soil fumigants
1,3-dichloropropene and chloropicrin are validated against the United States Department of Agriculture (USDA Salinity Laboratory)
soil physics model CHAIN_2D that was modified specifically for agronomic uses of soil fumigants. Comparison between model
predictions and field observations for six unique field trials in five different states indicate that CHAIN_2D effectively
captures the magnitude and duration of fumigant emission from soil observed experimentally with r
2
∼ 0.14–0.96 (avg. 0.66) for peak emission, and r
2
∼ 0.76–1.0 (avg. 0.91) for cumulative emissions (r equals the Pearson moment correlation coefficient). Correct prediction magnitudes suggest that CHAIN_2D is a useful tool
for extrapolating flux predictions to diverse scenarios not addressed by field trials. Examples of mitigation strategies such
as the use of agricultural films (tarps), increased soil injection depth, and management of soil water content, under near
semi-infinite parameter combinations of soil, meteorological, and agronomic properties are discussed. 相似文献
992.
S . Nolte C. van der Weyde P. Esselink C. Smit S. E. van Wieren J. P. Bakker 《Journal of Coastal Conservation》2017,21(3):369-379
Livestock grazing has been practiced in salt marshes in the Wadden Sea area since 600 B.C. Currently livestock grazing is also applied for conservation management. However, effects of such grazing management on salt marshes are likely to vary depending on the species of livestock and stocking density due to differences in the behaviour of the animals. Yet, little is known about the behaviour of different livestock species and stocking densities grazing in salt marshes. We studied the grazing behaviour of horses and cattle by focal observation in an experiment with four different grazing treatments on a coastal salt marsh. In all treatments we recorded diet choice, movement and grazing activity, and spatial distribution. Livestock species shared an overlap in diet choice. Yet, horses more often foraged on the short grass Puccinellia maritima, while the cattle diet contained a higher amount of Aster tripolium. Horses travelled longer distances per day and spent more time grazing than cattle. Spatial distribution of cattle was significantly clustered, while horses showed a random distribution utilizing the whole area. Animal behaviour differs between livestock species and stocking densities with respect to diet choice, activity and spatial distribution. 相似文献
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Irene T. M. Lindenburg Jeanine M. van Klink Vivianne E. H. J. Smits-Wintjens Inge L. van Kamp Dick Oepkes Enrico Lopriore 《黑龙江环境通报》2013,33(9):815-822
Perinatal survival rates after intrauterine transfusions (IUT) for red cell alloimmunisation now exceed 90%, which demonstrates the safety and efficacy of one of the most successful procedures in fetal therapy. However, improved perinatal survival could lead to an increased number of children with long-term disabilities. The importance of long-term follow-up studies in fetal therapy lies in both the necessity of evaluation of antenatal management as well as in evidence-based preconceptional and prenatal counselling. This review describes the possible long-term cardiovascular and neurodevelopmental sequelae after IUT treatment for different indications including red cell alloimmunisation, parvovirus B19 infection, fetomaternal haemorrhage and twin anaemia-polycythaemia sequence. © 2013 John Wiley & Sons, Ltd. 相似文献
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In this paper we argue that organizational identification is predictive of employee interests and concerns during periods of organizational change. More specifically, we assert that organizational identification may largely determine whether employees may be focused upon the change related outcomes (e.g., salary, expenses, etc.), or on the change processes (e.g., procedures, voice and participation options, etc.). Data of both a scenario experiment and a survey are presented indicating that high and low identifiers indeed are differentially interested in process and outcome information. The results suggest that people who identify less with the organization are more likely to be focused upon the change outcomes then on the change process, while people who identify highly (i.e., deep structure) with the organization are more likely to be focused upon the change processes then on the change outcomes. The benefits of awareness of organizational members' level of identification for organizational change management are discussed. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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