Results 21 to 30 of about 683,854 (208)

Alleviation of phosphorus rather than nitrogen limitation driven by permafrost and landscape effects on Dahurian larch forests

Functional Ecology, EarlyView.
Read the free Plain Language Summary for this article on the Journal blog. Abstract Permafrost thaw is reshaping nutrient dynamics in boreal forests, but its impacts on tree nutrient limitation and functional strategies remain poorly understood. Clarifying these responses is crucial for predicting the response of boreal forests to climate change.
Qiyue Fu, Liang Shi, Zhaopeng Song, Boyi Liang, Honglin He, Kun Yang, Weihua Zhang, Lisha Lyu, Anatoly S. Prokushkin, Hongyan Liu   +9 more
wiley   +1 more source

配电网保护间隙保护距离的研究

Dianci bileiqi, 2012
配电网保护间隙在提高线路跳闸重合率和防止架空绝缘导线雷击断线上,取得了较为显著的效果。但在实验中发现相对于避雷器动作时间,保护间隙动作时间和绝缘子动作时间相差不多。从保护间隙和避雷器动作时间不同出发,在分析保护间隙保护距离时考虑了保护间隙闪络时间对保护间隙保护距离的影响。先通过实验确定绝缘子和保护间隙的伏秒特性曲线,然后利用相交法计算出不同等级雷电过电压下保护间隙和绝缘子动作时间,最后根据保护间隙和绝缘子的动作时间差和雷电波在线路上传播的速度计算出不同等级雷电过电压下保护间隙的保护距离 ...
张东, 陶凤源, 许衡, 廖志华, 贾莹坤   +4 more
doaj  

Looking at Us Through Their Eyes. The Analytical Process from Ethnographic Perspectives1

Journal of Analytical Psychology, EarlyView.
Abstract This article looks at the analytical situation through the Others’ eyes—through examples from contemporary ethnographies of foreign cultures. It discusses the following issues: a) The analogy between the ontological worlds of the dead, ghosts, animals and dreams in “primitive populations” and the analytical psychological descriptions of the ...
Stefano Carta
wiley   +1 more source

道地药材保护性耕作对坡耕地土壤侵蚀的影响

Shuitu Baochi Xuebao, 2008
为有效防治坡耕地水土流失,提高坡耕地持续利用,于2007年选用甘草、板蓝根两种道地药材,在陇中黄土高原半干旱区的坡耕地上进行了道地药材保护性耕作防治水土流失效应的研究。试验设传统耕作下板蓝根与甘草间作(TIL)、春小麦与甘草间作(TWL)、免耕不覆盖下板蓝根与甘草间作(NTIL)、春小麦与甘草间作(NTWL)、免耕秸秆覆盖下板蓝根与甘草间作(NTSIL)、春小麦与甘草间作(NTSWL)6个处理,坡度在6°~7°之间,每个处理小区底部设径流收集池。结果表明:(1)保护性耕作具有良好的防止土壤侵蚀效应 ...
张晓艳, 王立, 黄高宝, 陈光荣
doaj  

When and why to give shorebirds a head start

Conservation Biology, EarlyView.
Abstract Headstarting is a translocation technique involving the hatching or rearing of wild eggs or young in captivity and the release of those individuals back to the wild at or before independence. It has been trialed as a conservation intervention for shorebirds over recent decades to improve the population trend of target populations by increasing
Lynda Donaldson, Alex Nicol‐Harper, Rebecca Lee, Nigel S. Jarrett, Geoff M. Hilton   +4 more
wiley   +1 more source

The collective application of shorebird tracking data to conservation

Conservation Biology, EarlyView.
Abstract Addressing urgent conservation issues, such as the drastic declines of North American migratory birds, requires creative, evidence‐based, efficient, and collaborative approaches. The abundance of over 50% of monitored North American shorebird populations has declined by over 50% since 1980. To address these declines, we developed a partnership
Autumn‐Lynn Harrison, Candace Stenzel, Alexandra Anderson, Jessica Howell, Richard B. Lanctot, Marley Aikens, Joaquín Aldabe, Liam A. Berigan, Joël Bêty, Erik Blomberg, Juliana Bosi de Almeida, Andy J. Boyce, David W. Bradley, Stephen Brown, Jay Carlisle, Edward Cheskey, Katherine Christie, Sylvain Christin, Rob Clay, Ashley Dayer, Jill L. Deppe, Willow English, Scott A. Flemming, Olivier Gilg, Christine Gilroy, Susan Heath, Jason M. Hill, J. Mark Hipfner, James A. Johnson, Luanne Johnson, Bart Kempenaers, Paul Knaga, Eunbi Kwon, Benjamin J. Lagassé, Jean‐François Lamarre, Christopher Latty, Don‐Jean Léandri‐Breton, Nicolas Lecomte, Pam Loring, Laura A. McDuffie, Rebecca McGuire, Scott Moorhead, Juan G. Navedo, David Newstead, Erica Nol, Alina Olalla‐Kerstupp, Bridget Olson, Elizabeth Olson, Julie Paquet, Allison K. Pierce, Jennie Rausch, Kevin Regan, Matthew E. Reiter, Amber M. Roth, Mike Russell, Daniel Ruthrauff, Sarah T. Saalfeld, Amy L. Scarpignato, Shiloh Schulte, Nathan R. Senner, Joseph A. M. Smith, Paul A. Smith, Zach Spector, Kelly Srigley Werner, Michelle L. Stantial, Audrey R. Taylor, T. Lee Tibbitts, Mihai Valcu, Nils Warnock, Walter Wehtje, Brad Winn, Michael B. Wunder   +71 more
wiley   +1 more source

玉米—马铃薯间作根系特征及其与坡耕地红壤径流中养分流失的关系

Shuitu Baochi Xuebao, 2017
农作物在生长过程中其根系对土壤的固持作用可以减轻坡耕地土壤的养分流失，测定农作物根系对径流中养分流失的影响可以从侧面评价不同作物的水土保持作用。选取云南主要农作物玉米、马铃薯为研究对象，测定了不同种植模式下作物生育期内坡耕地的产流次数、产流量、土壤侵蚀量、径流中养分流失量以及通过采用剪切箱，在农作物生育期对玉米、马铃薯单作与间作等3种种植模式下的作物根系特征进行了测定。结果表明，在常规管理条件下，与单作模式相比，间作模式具有明显减轻水土流失的作用。玉米马铃薯间作产流次数较马铃薯单作 ...
杜 静, 范茂攀, 王自林, 马志鹏, 马宇航, 李永梅   +5 more
doaj  

Constructed value of information with iterative scoring and parametric uncertainty to identify management‐relevant research priorities for a declining raptor species

Conservation Biology, EarlyView.
Abstract Constructed value of information (CVoI) is an expert elicitation decision‐analytic tool used to prioritize sources of uncertainty based on their potential to improve decision outcomes if resolved. Despite increased application of CVoI, the robustness of CVoI prioritization of sources of uncertainty relative to differences in expert elicitation
Kristin P. Davis, Mitchell J. Eaton, Emily R. Bjerre, Hillary M. White, Clint W. Boal, Jennifer H. Herner‐Thogmartin, Orin J. Robinson, Abigail J. Lawson   +7 more
wiley   +1 more source

MESO紧空间的MESO紧逆象(英文)

四川大学学报. 自然科学版, 2009
作者证明了meso紧映射逆保持meso紧性,作为应用,作者证明了正则空间中闭Lindelof映射逆保持meso紧性,进一步,作者指出定理条件中原象空间的正则性不可被省略而象空间的正则性可以用原象空间的正规性来替代。
沈荣鑫
doaj  

农作物棵间土面蒸发测定器

, 2010
本实用新型涉及一种农作物棵间土面蒸发测定器，该蒸发测定器是由内筒和外筒组成，在测量农作物棵间土面蒸发量时，将外筒埋于农作物棵间土中，在农作物棵间选取土场，去掉内筒的底盖，将内筒下端的内斜切口平放于土面，旋转内筒轻轻下压，当原状土柱装满内筒时，用力旋转切断土柱，提出内筒套上底盖称重，在将内筒放入外筒中进行观测，根据观测时间 ...
王积强.
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