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Matching expert range maps with species distribution model predictions
Conservation Biology, Volume 34, Issue 5, Page 1292-1304, October 2020., 2020 Abstract Species’ range maps based on expert opinion are a critical resource for conservation planning. Expert maps are usually accompanied by species descriptions that specify sources of internal range heterogeneity, such as habitat associations, but these are rarely considered when using expert maps for analyses.
Kumar Mainali +3 more
wiley +1 more source
Shuitu Baochi Xuebao, 2023 以明确自然界中广泛存在的层状结构土壤孔隙分布特征为目的。选黄土高原典型坝地土壤剖面为研究对象,利用CT扫描技术分析耕作层、犁底层、心土层土壤三维结构,探讨层状土孔隙参数随土层结构变化及界面层孔隙特征。结果表明:(1)瘦长型孔隙(孔隙形状系数≤0.2)是各土层土壤孔隙的主要形态。各土层的孔隙参数具有明显差异。耕作层的总孔隙度最高,大孔隙(≥1 mm)分布较多;犁底层孔隙总数量最高,含有较多孤立的小孔隙(≥0.1~0.5 mm)和微小孔隙(≥0.06~0.1 mm),但连通性最差 ...
张佐源 +5 more
doaj
Shuitu Baochi Xuebao, 2003 介绍了大孔隙流的概念和研究进展,对大孔隙的类型和在水文学上的分类方法进行了分析,并对大孔隙在土壤水分运动中的作用以及理论模式进行了探讨,分析了黄土的大孔隙发育特征和类型。论述了黄土区大孔隙流研究的必要性。
张建丰 林性粹 王文焰
doaj +2 more sources
Shuitu Baochi Xuebao, 2007 采集了太湖地区3种主要水稻土（白土、黄泥土和乌栅土）的原状土柱为供试土样，利用CT扫描技术，在不破坏土体结构的前提下，准确地得出了不同深度土壤剖面上各种大孔隙的数量、面积以及分布状况。结果表明，3种水稻土均以表层的大孔隙度最大，在30～40cm处达到一个最低点，再往下又呈波浪形变化。土柱各截面上大孔隙面积的变异系数随着深度的变化与大孔隙度相似，大孔隙度大的层次其变异系数也较大。等效直径越大的孔隙（〉5mm）在土壤不同深度下数量的变化也越大。表层上大直径（〉5mm）的大孔隙较多，在土壤剖面30 ...
吴华山, 陈效民, 陈粲
doaj +2 more sources
Impact Analysis of Earthquake-Induced Cracks in Deep Geological Repositories for Nuclear Waste Fuel [PDF]
, 2014 Based on the concept of deep geologic repositories, high-level radioactive waste will be stored in deep deposition holes away from the ground surface. The heat generated by the waste will induce both significant stress increments and ground water seepage
Bo-Sheng Jeng +9 more
core
Rare Metals, EarlyView.ABSTRACT The development of high‐performance electromagnetic protection materials integrating broadband absorption and effective shielding capabilities is hindered by challenges in simultaneously optimizing multiple electromagnetic properties through conventional material designs.
Changlong Du +9 more
wiley +1 more source
Rare Metals, EarlyView.ABSTRACT High‐entropy alloys (HEAs) have attracted considerable interest from researchers owing to their tunable chemical compositions, exceptional structural stability, and promising catalytic properties. However, their large‐scale application is often hindered by complex manufacturing techniques and poor durability.
Sheng Guo +9 more
wiley +1 more source
Shuitu Baochi Xuebao, 2020 冻融是影响高寒地区土壤结构的重要物理因素，以青海湖流域高寒草甸作为研究对象，通过野外采集原状土柱、室内冻融循环模拟、CT扫描和图像解译等方法，研究冻融循环对高寒草甸冻胀丘和丘间地的土壤大孔隙结构特征的影响。结果表明，随着冻融循环次数的增加，高寒草甸冻胀丘和丘间地土壤大孔隙度均呈现"减小—增加—减小"的趋势，冻融循环对土壤大孔隙度的降低主要在第1次冻融循环内形成的，且大孔隙的平均等效直径、平均体积、平均分枝长度、分枝密度和节点密度的变化规律与大孔隙度变化规律基本一致 ...
赵云朵, 胡霞
doaj
Velocity Analysis of a Flow Passing over a Vegetated Slope [PDF]
, 2014 A sheet flow or overland flow is simulated by the theory of laminar flow passing over a grassed slope with wood. The flow region is divided into two layers (vegetation layer & soil layer) or three layers (wood layer, vegetation layer & soil layer ...
Ching-Ya Tang +3 more
core
Micro pore characteristics of Luohe aquifer sandstone in Binchang Mining Area typical roof water hazard mines [PDF]
, 2023 The mining of Huanglong Coalfield faces a serious threat from roof sandstone water disaster of the extremely thick Luohe Formation. A laboratory study on the microscopic pore characteristics of the sandstone of the Luohe Formation in the Gaojiapu Coal ...
Chaofeng LI +4 more
core +1 more source