Results 11 to 20 of about 19,463 (115)
Shuitu Baochi Xuebao, 2004 通过6种地下水位控制处理和对照春玉米试验,探讨了地下水埋深对春玉米农田土壤水分、产量以及水分利用效率的影响。结果表明,地下水埋深对春玉米0～100cm层次土壤水分的影响较大。地下水位越浅这种影响显得越明显;无论地下水埋深深浅,田间累计地下水补给量变化规律可分为4个阶段,即稳定增长期、缓慢增长期、快速增长期和趋于稳定期。地下水位越高,累计地下水补给量越大,土壤排水量越大。较大降雨后土壤开始排水日期随着地下水埋深加深而滞后;地下水埋深1.0m时春玉米产量和水分利用率最高。地下水位在1.0m以下时 ...
巴比江 郑大玮 卡热玛·哈木提 孟翀 王占生 邱江泉
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Conservation Biology, EarlyView.Abstract Site fidelity is the tendency for animals to repeatedly return to the same locations, either within or between years. Site fidelity enables animals to utilize knowledge of previously visited locations, including assessments of seasonal variations in health and mortality risks (e.g., predation), resource availability, and social benefits such ...
Tobias A. Ross +13 more
wiley +1 more source
Shuitu Baochi Xuebao, 2011 长三角地区地下水位埋深较浅,容易受到污染,受污染的浅层地下水又可能成为农田向环境输送污染物质的主要载体之一.通过对该地区不同种植类型农田(水田、露天菜地)地下水为期12个月的水质监测,分析了地下水水质特征和氮素水质指标(NO3-N、NH4-N)的时空变异特征,结果表明:研究区域农田浅层地下水已受到了污染.参照我国地下水质量标准(GB714848-93),发现SO2-4和NH4-N是主要的污染指标.本区域地下水污染与农田施肥密切相关.同时发现研究区域地下水埋深与地下水中各无机离子没有明显相关性.0-300
金赞芳 +5 more
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Genomics‐informed management of ex situ populations
Conservation Biology, EarlyView.Abstract The European Association of Zoos and Aquariums (EAZA) manages insurance populations for hundreds of species through its EAZA ex situ programs (EEPs). EEPs help safeguard against extinction in the wild and provide source populations for genetic rescue programs.
Cock van Oosterhout +8 more
wiley +1 more source
Shuitu Baochi Xuebao, 2011 应用猪场废水处理工程中产出的厌氧水不同灌溉量和3个处理阶段出水与地下水按体积比1∶5混合对冬小麦-夏玉米轮作系统进行3年的小区灌溉试验,监测地下水的总矿化度及钾、钙、钠、镁等含量的变化。结果表明:(1)地下水中钾含量在厌氧水不同灌溉量条件下呈现高量厌氧水(Ha)>中量厌氧水(Ma)>低量厌氧水(La)的变化趋势,在混水灌溉处理地下水中钾含量均呈厌氧水与地下水1∶5混合(Tag)>原水与地下水1∶5混合(Tog)>仿生态塘水与地下水1∶5混合(Teg)的变化趋势;(2)地下水中钠、钙 ...
赵君怡, 张克强, 王风, 刘鸣达
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International Journal of Applied Linguistics, EarlyView.ABSTRACT Research on English‐Medium‐Instruction (EMI) highlights inadequate support for students transitioning from L1‐medium‐instruction to EMI. To date, little research has focused on how L2 students’ adaptation to an EMI environment influences their L2 learning motivation (LLM).
Kevin W. H. Tai
wiley +1 more source
Journal of Sociolinguistics, EarlyView.ABSTRACT This study investigates how ordinary Taiwanese netizens perform linguistic authority by policing others’ use of Mainland Chinese expressions in everyday online interactions not originally intended to be political and how such policing is subsequently supported, resisted, or (de)legitimized in the context of Taiwan–China relations. Three orders
Hsi‐Yao Su
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Shuitu Baochi Xuebao, 2006 选择吉林省西部典型苏打碱化土壤地区，对其地下水的基本水化学指标进行了测定，分析了地下水电导率与含盐量、矿化度和离子含量的关系。针对地下水离子组成的特点，对该区地下水的苏打碱化特征进行了分析。最后分别以电导率、矿化度和钠吸附比（SAR）为指标，对该区地下水质进行了初步评价与分级。
李彬, 王志春, 梁正伟, 迟春明
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Shuitu Baochi Xuebao, 2008 对奇台县坎儿井分布状况、兴衰过程、地质情况、地下水位实地调查和其社会经济的资料分析表明,奇台县坎儿井经历了从1949年开挖,20世纪60年代初数量达到最多,20世纪80年代初期全部废弃的一个由兴到衰的过程。人口增加和农业生产的发展是导致地下水位迅速下降、坎儿井干枯的根本原因。坎儿井数量变化过程与人口、耕地增加过程早期基本一致,后期变化方向相反。人口数量达到90 000人,水浇地为50 000 hm2时,平均地下水埋深为5 m左右,坎儿井开始衰亡。坎儿井全部废弃时平均地下水位约深8 m,此时 ...
XIONG, HAN
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Compliance in Regulatory Gray Areas: The Case of the Organic Seed Standard
Policy Studies Journal, EarlyView.ABSTRACT Adaptive regulations, designed to balance flexibility with accountability, can embed provisions that unintentionally leave room for firms to shirk on their responsibilities by exploiting flexibility. We call these provisions “regulatory gray areas,” and ask: how should we understand (non‐)compliance in adaptive regulatory settings?
Liza Wood +3 more
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