Results 41 to 50 of about 1,961 (166)
为揭示雨强对喀斯特坡耕地养分流失的影响,运用可调坡度、地下孔(裂)隙度试验钢槽装填土石模拟喀斯特裸露坡耕地,采用人工模拟降雨的方法研究不同雨强下喀斯特裸坡径流养分流失特征。结果表明:(1)雨强为15,30 mm/h时地表不产流,雨强50 mm/h时地表有产流;试验雨强下地下孔(裂)隙均有径流产生。(2)地表径流中全氮和全钾流失量均随雨强增大而增大,全磷流失量则先增大后减小;地下径流中全氮流失量随雨强增大呈先增大后减小趋势,全钾流失量与雨强正相关,全磷流失量与雨强关系不明显。(3)雨强为30,50 mm ...
靳 丽 +4 more
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Study of Sound Characteristics of Rain Noise at Sea [PDF]
海上降雨引起的噪声信号(简称降雨噪声)是海洋环境噪声背景场的一个重要干扰源,会极大地降低声呐的检测能力,影响水声通信的应用频段和降低水声设备的性能。考虑未来的海战极可能是在恶劣天气(往往伴随疾风暴雨)下进行,充分掌握降雨噪声的特性,不仅在军事上有利于检测海洋环境噪声背景中的干扰源,提升水声设备的作战效能,而且在民用上可拓展应用声学方法监测海上降雨的技术。近几十年来,美国等发达国家为了解释降雨噪声的产生机制,对自然界的降雨噪声开展了大量观测。前期的研究成果表明 ...
刘贞文
core
Analysis of geological hazards caused by the “23 • 7” heavy rainfall in the northern section of Taihang Mountain in Hebei Province [PDF]
Heavy rainfall is the main factor triggering geological disasters. In the northern region of China, most of the researches focus on the geologic disasters caused by short-term heavy rainfall, and the researches on the characteristics of geologic ...
Fuji GU +6 more
core +1 more source
Some extinctions can be prevented if impediments to protection of threatened species are overcome. Policies and practices have failed endangered species and biodiversity conservation is fraught with impediments such as rhetorical adoption, policy dismantling, circumvention of legislative obligations, and deliberate ignorance of scientific evidence ...
Noel Preece +2 more
wiley +1 more source
利用遂宁水土保持试验站5个径流小区1984—2015年次降雨和径流输沙数据,基于降雨过程定量划分出4种雨型,分析了雨型对不同坡度坡耕地产流产沙的作用。结果表明:径流深与各时段最大雨强均呈极显著相关(p<0.01),随着坡度的增加,最大相关系数所对应的雨强时段越短;冲刷量均与I平均呈极显著相关,且相关系数最大。径流深、冲刷量与雨强拟合关系均为幂函数,分别为“凸型”和“凹型”增函数,且拟合度区间分别为[0.79,0.88]和[0.90,0.97],说明冲刷量和雨强的关系更密切 ...
马, 陈, 单志杰, 郎登潇, 廖
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In this study, we show that environmental food availability influences wildlife detection probability when using food baits. We sampled small mammals in Borneo with live traps baited with fruit before, during and after the rainforest experienced a mast fruiting event, which drastically altered environmental food availability.
Bastien Dehaudt +3 more
wiley +1 more source
弃土场是开发建设项目中最重要的水土流失来源之一。以辽宁省沈阳市某电厂剥离表土临时堆土为对象,研究棕壤地区开发建项目设弃土的流失规律。试验在沈阳农业大学水利学院综合试验基地的人工模拟降雨试验大厅内进行,共设5个雨强、5个坡度,雨强分别为0.38,0.64,1.05,1.24,1.50 mm/min,坡度分别设定为20°,25°,30°,35°,40°。研究结果表明,相同条件下,雨强越大坡面产流时间越短,坡面土壤水分入渗率随雨强的增加而增加,且雨强越大坡面初始入渗率越高;径流量随雨强的增加而增加 ...
苏芳莉 +4 more
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The Effectiveness and Feasibility Analysis of Low Impact Development Stormwater Management in Xiamen Island [PDF]
传统的以末端治理为主的雨洪管理措施已不能满足城市健康发展的需要,城市发展需要具有可持续性的雨洪管理策略。低影响开发雨洪管理(LID)通过模拟场地开发前的水文状况,采用分散、多样、小型、本地化的技术从源头上截流、储存、渗滤以及蒸发雨水,最大程度保护开发改造地区的水文情势,减少负面环境影响。学习借鉴这种新策略,对改善我国城市新区开发和旧城改造的雨水资源利用与管理是十分有意义的。 本研究融合多学科知识,对某处植草砖铺设停车场和某半密集型绿色屋顶的雨洪处理能力进行野外监测 ...
刘保莉
core
Abstract Reintroduced populations are typically considered to progress through establishment, growth, and regulatory phases. However, most reintroduction programs do not monitor intensively enough to test this conceptual model. We studied population indices derived from track activity of 4 threatened species (greater bilby [Macrotis lagotis], burrowing
Katherine E. Moseby +3 more
wiley +1 more source
自然条件下降雨多以间歇形式出现,而坡面土壤侵蚀又是一个渐变发育的复杂过程。通过3个雨强(60,90,120 mm/h)、5个坡度(5°,10°,15°,20°,25°)下的15场室内模拟降雨,研究一、二次降雨条件下不同雨强、坡度及降雨量对红壤坡面径流和侵蚀过程的影响,探讨间歇降雨条件下坡面侵蚀发育过程及其主要影响因素的变化。结果表明:(1)二次降雨的产流时间相比一次降雨均提前,一次降雨径流总量受到雨强、坡度和降雨量的共同影响,15°坡度是径流总量变化的一个转折点,二次降雨时降雨量的作用减弱 ...
李霞 +6 more
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