Results 21 to 30 of about 2,458 (102)
切沟侵蚀是一种常见的土壤侵蚀现象,切沟侵蚀定量研究可以进一步揭示切沟侵蚀规 律,为建立切沟侵蚀预报模型、切沟侵蚀危害的评估与治理提供科学的依据.介绍了近 年来有关切沟侵蚀定量研究的主要进展,对目前主要方法的适用范围、优点及局限性进行了讨论,并指出切沟侵蚀定量研究中亟待解决的问题和研究方向.
程宏, 伍永秋
doaj +2 more sources
甘肃省小陇山林区降雨型浅层滑坡汇水面积-坡度关系及其影响因素
沟头发生侵蚀的地形临界模型可有效预测侵蚀沟的形成条件,浅层滑坡失稳形成的洼地也是沟头形成的方式之一。为探究浅层滑坡临界起动模型的特点,以甘肃省天水市小陇山林区的降雨型浅层滑坡为研究对象,运用汇水面积-坡度关系,构建临界起动模型,与黄土高原典型侵蚀沟(浅沟、切沟)的临界起动模型进行对比分析,并探讨土地利用类型、植被类型和土壤质地对该模型的影响。结果表明:(1)浅层滑坡临界起动模型为S=3.50As-0.34,其侵蚀阈值为3.50,大于黄土高原典型浅沟(0.96)和切沟(1.54)的侵蚀阈值 ...
张晓曼 +4 more
doaj
ABSTRACT This systematic review examines the digital health interventions for inclusive and equitable solutions for transforming healthcare access and delivery in Nepal. The research focuses on improving digital health accessibility among marginalized and rural populations of Nepal.
Manoj Kumar Dahal, Gary L. Kreps
wiley +1 more source
ABSTRACT Water security in tropical regions faces escalating pressures from climate change, land‐use shifts, and population growth. We conducted a bibliometric review of 1146 peer‐reviewed articles (1964–2023) on tropical water security. Latent Dirichlet Allocation identified 13 thematic topics and their evolution. Publications rose sharply after 2012,
Karling Fernanda Schuster +3 more
wiley +1 more source
This photo displays one of our camera locations within the core area of Mt. Siguniang National Nature Reserve, China. The site features steep scree slopes and > 1000 meters elevational gradient with minimal anthropogenic disturbance. Camera traps captured three unique snow leopard individuals (Mr.
Dongrui Wang +6 more
wiley +1 more source
Abstract The birth of a child has been associated with a decline in couple satisfaction, which has implications for the child's social‐emotional development. This study investigated the potential spillover effect on pregnant women's perceptions of their relationships with their partners of the Supporting the Transition to and Engagement in Parenthood ...
Nicolas Berthelot +5 more
wiley +1 more source
黄土洞穴与滑坡、沟蚀等侵蚀过程联系紧密并加剧了黄土高原的水土流失程度,但目前黄土洞穴发育的分布特征与侵蚀临界暂未明晰。利用无人机获得了研究区高分辨率影像与数字表面模型,基于影像标识了黄土洞穴并统计了其土地利用类型与洞穴直径,利用标识点在数字表面模型上提取了黄土洞穴的坡度、坡向、曲率和汇水面积等地形数据并分析了黄土洞穴的分布特征。结果表明 ...
郑炜珊 +3 more
doaj
侵蚀沟形态特征是了解沟蚀发生、发育的关键性因素, 探究不同季节侵蚀沟形态参数变化特征对深入理解侵蚀沟的侵蚀过程和侵蚀沟的治理工作具有重要意义。选取黑龙江省海伦市光荣小流域内的3条侵蚀沟为研究对象, 探究季节变化下侵蚀沟长度、面积、体积等形态参数值的差异。结果表明: (1)不同季节侵蚀沟横断面形态由沟头到沟尾均呈现出由"V"形向"U"形转变; (2)侵蚀沟在降雨期由沟头前进和沟尾后退所引起的长度增加量大于融雪期由沟头前进所引起的长度增加量; (3)侵蚀沟面积在降雨期的增加量大于融雪期 ...
宋爽, 范昊明, 牛天一
doaj
以无人机为主体的天地一体化立体测量为地表精准快速测量提供了有利条件。无人机拍摄正射影像时,陡坡影响拍摄视角,可能对地表三维测量精度产生影响。选取发展大型切沟(BG)、稳定中型切沟(MG)和小型浅沟(SG),采用三维激光扫描(Terrestrial Laser Scanning,TLS)和无人机正射摄影(Structure from Motion,SfM)2种方法获取地表DSM(Digital Surface Model,数字表面模型),并以TLS的DSM为基准,分析了坡度对SfM的DSM的高程误差的影响。
甄怀才 +6 more
doaj
选取黄土丘陵区岔巴沟流域不同位置和不同沟道级别的30条典型切沟为研究对象,基于三维激光扫描技术(LIDAR),建立了基于高分辨率DEM提取切沟形态特征的方法,对比分析了0.1 m与5 m 2种分辨率DEM提取切沟形态特征参数的差异,实现对低分辨率DEM提取的切沟形态特征参数向高分辨率尺度转化。结果表明:基于三维激光扫描技术获取的0.1 m高分辨率DEM提取到的切沟形态特征值与手工测量的切沟形态特征值之间无显著差异,三维激光扫描技术提取切沟长度、宽度、深度、表面积和体积分别是手工测量的94.0%,109 ...
吴红艳, 徐锡蒙
doaj

