Results 21 to 30 of about 13,162 (121)
Shiyou jixie, 2014 水下生产系统正常运行或因事故关停时，由于海水的冷却作用，易产生水合物并发生沉积，从而堵塞油气通道，严重影响油气田安全高效生产，因此有必要对水下生产系统水合物防治技术展开专题研究。分析了水合物的形成机理，重点介绍了国外水合物防治的主要方法及应用情况，包括化学注入法、隔热保温法、电加热法以及隔热保温层与化学注入相结合法。简述了水下生产系统的“冷点”管理，指出“冷点”一般位于传感器、闸阀驱动器和接头等部位。最后建议国内加大化学注入剂、隔热保温材料等的自主研发力度，并开展水合物防治工艺研究。
赵旭东, 邓平, 刘文霄
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Shuitu Baochi Xuebao, 2023 黄河流域经济带是我国北方重要的经济走廊,科学评估黄河流域经济带生态环境绩效水平,提高黄河流域沿线9省生态环境质量是实现黄河流域经济带的高质量发展重要举措之一。运用生态环境质量评估、生态效率评估等研究方法,开展2012—2017年的生态环境质量、生态效率和绿色全要素生产率评估。结果表明:黄河流域经济带生态环境绩效水平总体呈现由较低水平不断提升的趋势;黄河沿线九省在生态环境质量和生态效率系统层中有明显差异,生态环境质量系统层中,上游地区的最优;生态效率系统层中,中下游地区的生态效率最优且稳定 ...
鲁仕宝, 尚毅梓, 王浩, 廉志端
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Global drivers of the conservation–invasion paradox
Conservation Biology, Volume 39, Issue 5, October 2025.Abstract The conservation–invasion paradox (CIP) refers to a long‐term phenomenon wherein species threatened in their native range can sustain viable populations when introduced to other regions. Understanding the drivers of CIP is helpful for conserving threatened species and managing invasive species, which is unfortunately still lacking. We compiled
Yanhua Hong, Zhiyong Yuan, Xuan Liu
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Shuitu Baochi Xuebao, 2007 基于土柱实验，对有作物生长条件下的污水灌溉土地处理慢渗系统氮素去除和作物生长状况开展实验研究，探讨在灌溉原污水中添加有机碳对该系统去除氮素和作物生长状况产生的影响作用。实验研究结果表明，随着灌溉原污水中有机碳含量的逐渐增加，污水灌溉土地处理慢渗系统下排的水量有所增大，排水中的氮素（铵态氮、硝态氮、总氮）淋溶量和化学需氧量有所增加，而作物的干物质量和吸氮量则明显下降；增加灌溉原污水中的有机碳含量，会影响污水灌溉土地处理慢渗系统去除氮素的效果和作物生长条件，在增加基于硝化和反硝化作用的除氮量同时 ...
焦平金, 许迪, 程先军
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Seasonality of temperature dependence of methane fluxes from natural wetlands
Functional Ecology, Volume 39, Issue 9, Page 2383-2397, September 2025.Read the free Plain Language Summary for this article on the Journal blog. Abstract Temperature dependence is a crucial parameter in estimating methane (CH4) fluxes from natural wetlands, yet our understanding of this parameter remains inadequate. Seasonal fluctuations in water levels and ecosystem productivity lead to seasonal differences in CH4 ...
Jinshuai Li +6 more
wiley +1 more source
Shuitu Baochi Xuebao, 2005 以河北省曲周县为例，研究了现代农业生态系统的能值演替情况。结果表明，曲周农业生态系统年总投入能值和总产出能值均呈增加趋势，其中农业投能以系统以外的化石能投入为主，系统环境资源投能的绝对数也在增加，主要表现在对地下水的开采利用上；总产出能值先以种植业产出能值占绝对优势后演替为农牧结合同时兼顾林业和渔业发展的能值产出形式，但农牧业系统多样性降低；农业发展在全国居于较好水平，仍有较大的发展潜力，但能值产出效率增加幅度减慢，系统连接网络不佳，优势度呈下降趋势 ...
张洁瑕 郝晋珉 段瑞娟
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Opportunities, research gaps, and risks in allogenic ecosystem engineer mimicry
Conservation Biology, Volume 39, Issue 4, August 2025.Abstract In an age of anthropogenically driven species loss and increasingly novel ecosystems, ecosystem engineer restoration is a process‐based approach to supporting ecosystem function. Many ecosystem engineers have low or declining population sizes.
Brandi Goss +2 more
wiley +1 more source
Shuitu Baochi Xuebao, 2011 以天山中部天然云杉林森林生态系统为研究对象,以250 hm2流域尺度为单元,采用流域试验和水量平衡样地相结合的方法,对森林生态系统的月水文过程进行全面、系统地研究。结果表明:(1)在降雨分配过程中,80.39%的雨量分配是在土壤层完成的;其次,林冠截留率较大,占降雨量的17.92%,并且随着林龄的增大,单位面积产生的截留越强;单位面积产生径流量最小,仅为降雨量的2.75%,其中,单位面积裸地的产流最大,分别为草地和林地的5.4,12.5倍。(2)蒸发散是流域森林生态系统的最大损耗方式 ...
李海军 +5 more
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Functional Ecology, Volume 39, Issue 6, Page 1550-1566, June 2025.Read the free Plain Language Summary for this article on the Journal blog. Abstract Forests store substantial amounts of soil organic carbon (SOC), but SOC stocks differ strongly between forest ecosystems dominated by arbuscular mycorrhizal (AM) or ectomycorrhizal (EcM) fungi.
Mengxu Zhang +10 more
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Assessing Closed Hydroponic Subsystems for Batavia Lettuce Growth Under Different Planting Densities
World Water Policy, Volume 11, Issue 2, Page 427-438, May 2025.ABSTRACT Hydroponic systems have the potential to be sustainable and alternative methods for food production that confer advantages of high production and better control of growth. However, only a few studies have focused on leafy vegetable growth in different subsystems and environmental variables.
Demet Çekin +6 more
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