Results 31 to 40 of about 2,230 (137)

The need for carbon finance schemes to tackle overexploitation of tropical forest wildlife

open access: yesConservation Biology, Volume 39, Issue 1, February 2025.
Abstract Defaunation of tropical forests, particularly from unsustainable hunting, has diminished populations of key seed dispersers for many tree species, driving shifts in forest community composition toward small‐fruited or wind‐dispersed trees with low wood density. Such shifts can reduce aboveground biomass, prompting calls for overexploitation to
Caroline E. Milson   +3 more
wiley   +1 more source

不同雨型下紫色土区坡耕地产流产沙特征

open access: yesShuitu Baochi Xuebao, 2017
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
doaj  

极端短历时暴雨下城市内河水文风险动态预警模型

open access: yes水电水利
极端短时暴雨会快速抬高城市内河水位,造成排水系统过载,加大局部内涝隐患。立 足城市内河水文风险动态预警需求,整合雨强、水位、汇流过程、排涝能力等指标搭 建风险识别模型,剖析暴雨下河道水文变化特征与风险演变趋势,建立分级预警实时 更新机制。研究能够提升城市内河洪涝风险辨识水平,为防汛调度、排涝决策与城市 安全管理提供技术支撑。
涛 张
semanticscholar   +1 more source

State infrastructural power in a neopatrimonialist democratization context: Why Tunisian sustainable land management fails

open access: yesReview of Policy Research, Volume 41, Issue 6, Page 985-1016, November 2024.
Abstract Sustaining agricultural production in arid and semi‐arid regions is of paramount importance to food security, geo‐political independence, and social stability. In this context, it is vital to understand the effectiveness of policies. In this article, we aim to answer the question of what role the state and its policies play for soil protection
Andreas Thiel   +3 more
wiley   +1 more source

辽宁棕壤区开发建设项目弃土流失特征研究

open access: yesShuitu Baochi Xuebao, 2011
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
doaj  

水利水电工程高边坡喷锚支护与汛期坡面排水协同施工技术研究

open access: yes水电科技
水利水电工程高边坡因所处区域的地形条件复杂、汛期降雨强度大且集中,容易发生支护体系失稳破坏、坡面冲刷侵蚀等,对工程的施工安全有着直接的影响。喷锚支护能够有效控制岩体变形,汛期坡面排水能够削弱水对边坡的影响,虽然两者的协同作业是保障高边坡稳定的关键环节,但是在具体的施工过程中仍存在一些不足,例如工序衔接不顺畅等、参数匹配不合理等。基于此,文章充分围绕高边坡施工的特性进行深入探究,制定一套科学可行的协同施工技术方案,为水利水电工程高边坡汛期施工安全提供技术支撑。
俊杰 张
semanticscholar   +1 more source

A prospective study evaluating the correlation between local weather conditions, pollen counts and pruritus of dogs with atopic dermatitis

open access: yesVeterinary Dermatology, Volume 35, Issue 5, Page 500-507, October 2024.
Abstract Background Canine atopic dermatitis (cAD) is a hereditary, generally pruritic and predominantly T‐cell‐driven inflammatory skin disease, involving an interplay between skin barrier abnormalities, allergen sensitisation and microbial dysbiosis.
L. Widorn   +2 more
wiley   +1 more source

间歇降雨对红壤坡面土壤侵蚀特征的影响

open access: yesShuitu Baochi Xuebao, 2021
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
doaj  

不同草种配置下植生混凝土边坡的抗冲刷与蓄水性能研究

open access: yes中国科学与技术学报
为提升多雨地区植生混凝土边坡的生态防护效果,系统研究了不同草种配置下的植物生长适应性、坡面抗冲刷性能及蓄水能力。选用狗牙根、黑麦草、高羊茅、四季青四种草本植物,设置无植被、单播、混播三种配置方式,基于自制模拟降雨装置,测试了坡度(30°、45°)和降雨强度(34 mm/h、144 mm/h)下的坡面径流率与侵蚀率,并评价了植生混凝土的蓄水能力。结果表明:(1)四种植物生长速度排序为:黑麦草>狗牙根>四季青>高羊茅,35 d 平均高度分别为16.2cm、14.1cm、12.5cm、10.7cm;“黑麦草 ...
曹粲然   +8 more
semanticscholar   +1 more source

Demographic and net primary productivity dynamics of primary and secondary tropical forests in Southwest China under a changing climate 气候变化背景下中国西南热带原始林和次生林的群落和净初级生产力动态研究

open access: yesIntegrative Conservation, Volume 3, Issue 3, Page 230-243, September 2024.
Tropical secondary forest at early sucessional stage had higher diamter growth rate and mortality rate, however, these forests also are more risked to droughts and high temperatures. Rising temperatures and more frequent droughts may decrease the carbon sink capacity of tropical forest ecosystems. Abstract Tropical forests are major carbon sinks on the
Sai Tun Tun Oo   +11 more
wiley   +1 more source

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