Results 11 to 20 of about 97,430 (140)

Identifying socioeconomic and biophysical factors driving forest loss in protected areas

open access: yesConservation Biology, Volume 37, Issue 4, August 2023., 2023
Abstract Protected areas (PAs) are a commonly used strategy to confront forest conversion and biodiversity loss. Although determining drivers of forest loss is central to conservation success, understanding of them is limited by conventional modeling assumptions.
Kathryn A. Powlen   +3 more
wiley   +1 more source

A spatially explicit empirical model of structural development processes in natural forests based on climate and topography

open access: yesConservation Biology, Volume 34, Issue 1, Page 194-206, February 2020., 2020
Abstract Stand structure develops with stand age. Old‐growth forests with well‐developed stand structure support many species. However, development rates of stand structure likely vary with climate and topography. We modeled structural development of 4 key stand variables and a composite old‐growth index as functions of climatic and topographic ...
Yuichi Yamaura   +6 more
wiley   +1 more source

乌拉山废弃矿区坡长对客土坡面产流产沙与沟蚀特征的影响

open access: yesShuitu Baochi Xuebao, 2022
为研究不同坡长客土坡面产流产沙及沟蚀特征差异变化,通过设计2个坡度(15°,20°)下不同坡长(2,4,6,8,10 m)的野外径流小区进行冲刷试验。结果表明:(1)初始产流时间变化范围与产流停止时间均随坡长增加而增大,产流率初期快速增加,达到初次峰值后呈现不规律波动,累积产流量随坡长增加而增多;产流率、累积产流量与坡长、产流时间及其交互作用呈极显著相关(p<0.01),累积产流量在2种坡度下均与坡长、产流时间呈幂函数相关。(2)产沙率初期快速增加,达到初次峰值后随冲刷时间逐渐下降 ...
张馨予   +6 more
doaj  

长江三峡工程库区宝塔坪滑坡前缘塌岸预测及防护 [PDF]

open access: yes, 2003
以长江三峡工程库区奉节宝塔坪滑坡为例,介绍滑坡前缘塌岸预测及防护工程设计方法,重点是石笼垫护坡设计。宝塔坪库岸段潜在的塌岸部位是滑坡前缘地带,该处阶地发育,仅第四系松散堆积物厚度即达50m以上。水库塌岸预测首先在滑坡前缘工程地质分带的基础上进行,对不同的分带用卡丘金法分别预测塌岸宽度,并对预测要点给予详细的说明。其次,分析了塌岸对滑坡稳定性的影响。这些工作揭示了滑坡体前缘防护的必要性。最后针对三峡水库运行特点及宝塔坪滑坡工程地质条件,确定滑坡前缘护坡工程方案,即自145m ...
苏爱军   +4 more
core   +2 more sources

基于无人机航摄的坡形对浅沟发育的影响

open access: yesShuitu Baochi Xuebao, 2022
为探究坡形对浅沟发育的影响,以陕西省靖边县狼儿子沟无人机航摄影像为基础数据,通过目视解译得到浅沟(指瓦背状地形底部)225条,统计了浅沟条数、浅沟长度、沟头到分水岭的距离及浅沟密度等指标。利用浅沟地形分水线上的高程点进行插值得到原始坡面数字高程模型(digital elevation model,DEM),以此DEM提取地形曲率以表征坡形,进而分析坡形与浅沟指标的关系。结果表明:(1)以浅沟地形分水线上的高程点插值后的DEM对浅沟进行了综合,能较好地表达浅沟发育之前原始坡面的地形特征。(2 ...
王海于   +4 more
doaj  

Achieving Transboundary Water Security Through Water Innovations: A Framework and Cases

open access: yesWorld Water Policy, Volume 12, Issue 1, February 2026.
ABSTRACT Alternative sources of freshwater, provided by various innovations, have long been available to countries facing acute water stress. We hypothesize that avoiding and/or resolving conflict with neighbors—caused by the uncertainty of continued access to shared surface water and groundwater sources—is another driver of innovation adoption ...
David Lewis Feldman
wiley   +1 more source

翻耕除草对不同坡长下紫色土氮磷流失的影响

open access: yesShuitu Baochi Xuebao, 2020
为揭示自然降雨下翻耕除草和坡长对紫色土氮、磷流失的影响,通过野外设置径流小区(2个坡面:翻耕除草与自然恢复;3种坡长:20,40,60 m,共9个小区),定位监测研究不同处理下产流产沙及氮、磷流失特征。结果表明,同一坡面不同坡长间产流产沙差异不显著(P>0.05);同一坡长不同坡面处理小区的径流量、产沙量差异极显著(P0.05),其他坡长DN、DP流失量差异显著 ...
梁珂   +4 more
doaj  

Indian Pangolin in Lamjung Requires Urgent Attention 尼泊尔拉姆琼县地区的印度穿山甲急需关注

open access: yesWildlife Letters, Volume 2, Issue 4, Page 204-213, December 2024.
This study documented the first evidence of the Indian pangolin in Lamjung district, Nepal, finding three burrows and rescue evidence in Simalchaur Naringhat Community Forest. The burrows identified at an elevation of 530 m and characterized by moderate crown and ground cover (26%–50%), a 25° slope, and predominantly red soil, are indicative of a ...
Asmit Neupane   +4 more
wiley   +1 more source

坡度对坡面土壤侵蚀的影响分析

open access: yes, 2001
在运动波理论基础上,就影响土壤侵蚀的主要因素,包括降雨超渗净雨量,坡面流水深、流速和切应力,以及土壤抗冲蚀能力等随坡度的变化关系进行了理论分析。并进一步对坡面土壤侵蚀的坡度界限做了较细致分析,表明坡度界限是一个变量,随颗粒粒径、容重、坡面糙率、径流长度、降雨入渗差值(净雨量),以及土壤摩擦系数等因素的不同而改变,给出了界限坡度的变化规律,并得出一般情况下土壤侵蚀的坡度界限值应在41.5°~50 ...
陈力, 李家春, 刘青泉
core   +2 more sources

Patterns of recovery in extant and extirpated seabirds after the world's largest multipredator eradication

open access: yesConservation Biology, Volume 38, Issue 4, August 2024.
Abstract Eradicating invasive predators from islands can result in substantial recovery of seabirds, but the mechanisms that drive population changes remain poorly understood. Meta‐analyses have recently revealed that immigration is surprisingly important to the recovery of philopatric seabirds, but it is not known whether dispersal and philopatry ...
Jeremy P. Bird   +2 more
wiley   +1 more source

Home - About - Disclaimer - Privacy