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Development of crop coefficient (Kc), the ratio of crop evapotranspiration (ETc) to reference evapotranspiration (ETo), can enhance ETc estimates in relation to specific crop phenological development. This research was conducted to determine growth-stage-specific Kc and crop water use for cotton (Gossypium hirsutum) and wheat (Triticum aestivum) at the Texas AgriLife Research field at Uvalde, TX, USA from 2005 to 2008. Weighing lysimeters were used to measure crop water use and local weather data were used to determine the reference evapotranspiration (ETo). Seven lysimeters, weighing about 14 Mg, consisted of undisturbed 1.5 m × 2.0 m × 2.2 m deep soil monoliths. Six lysimeters were located in the center of a 1-ha field beneath a linear-move sprinkler system equipped with low energy precision application (LEPA) and a seventh lysimeter was established to measure reference grass ETo. Crop water requirements, Kc determination, and comparison to existing FAO Kc values were determined over a 2-year period on cotton and a 3-year period on wheat. Seasonal total amounts of crop water use ranged from 689 to 830 mm for cotton and from 483 to 505 mm for wheat. The Kc values determined over the growing seasons varied from 0.2 to 1.5 for cotton and 0.1 to 1.7 for wheat. Some of the values corresponded and some did not correspond to those from FAO-56 and from the Texas High Plains and elsewhere in other states. We assume that the development of regionally based and growth-stage-specific Kc helps in irrigation management and provides precise water applications for this region. 相似文献
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郭琼 《农业图书情报学刊》2012,24(1):79-82,89
通过对农业部机关图书馆近三年馆藏流通情况的统计,分析了国家机关公务员的阅读倾向,提出了加强机关图书馆馆藏建设,提高文献服务质量的若干对策。 相似文献
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公务员是国家公务的执行者,依法行使行政权力。在改革开放和建设有中国特色社会主义的伟大实践中,我国公务员队伍的主流是好的,有着良好的社会主义道德风尚。但是由于种种复杂的原因,导致一些公务员行政道德有一定程度滑坡,行政道德行为失范现象屡见不鲜,甚至出现腐败现象。因此,加强对我国公务员行政道德行为的规制,进一步完善我国公务员制度,意义重大。 相似文献
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刑事和解在我国有着深厚的文化和思想渊源,是对我国优良传统的传承,也是和谐理论在刑事司法实践中的体现。本文对我国构建刑事和解制度的历史文化基础进行了分析。 相似文献
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本文在阐述负债经营为企业带来诸多经济利益的同时,也阐述了它给企业带来的财务风险。控制财务风险的关键在于把握负债经营的适度性。为此,着重论述企业如何通过财务管理手段,并运用一系列财务指标的计算、预测和分析,确定负债经营的最佳度,尽可能地降低负债经营的财务风险 相似文献
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在市民社会理论的基础上,通过分析农村经济、农民自治、农村文化3个方面,探讨了市民社会对农村改革发展的功能. 相似文献
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培育和谐图书馆文化是提高全民阅读率的有效途径 总被引:2,自引:0,他引:2
阐述培育和谐图书馆文化的重要性、构建和谐社会过程中全民阅读的现状以及和谐图书馆文化对全民阅读的影响,提出了培育图书馆文化提高全民阅读率的策略. 相似文献
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Sustainability has been the subject of prolonged debate within both academic and mainstream literature, rendered all the more
heated because many of the disagreements come down to deep differences in values. These "value wars' play out in decisions
made about issues ranging from development and investment to livelihoods and agriculture. Using rural communities as the context
for discussion, this article proposes new directions for this contested concept, based on the life code of values. These life
values ground sustainability in a multi-scalar web of everyday acts of human community. From this life-values perspective,
compound terms such as sustainable agriculture and sustainable rural communities gain new meaning and offer the potential
for the basis of a rural renaissance.
Jennifer Sumner is an Assistant Professor in the Adult Education and Community Development Program at OISE/University of Toronto, Canada.
Her interdisciplinary research interests include sustainability, globalization, rural communities, and the civil commons as
well as adult education and critical pedagogy. She is currently researching the links between organic agriculture and sustainability. 相似文献