Results 91 to 100 of about 9,608 (155)
Shuitu Baochi Xuebao, 2004 用传统统计和地统计方法相结合，对甘肃省武威及张掖灌漠土耕层土壤有效B，Cu，Fe，Mn及Zn等微量元素的空间变异特征进行了研究。结果表明：武威土壤有效Zn和Fe普遍缺乏，张掖土壤除Zn较缺乏外，其余元素均较充足。描述性统计结果显示不同土壤微量元素的变异程度各不相同。地统计分析结果表明，武威和张掖土壤微量元素空间分布的最大相关距分别在192～477m及141～206m之间；武威土壤中除有效B含量具有中等的空间自相关性外，其余微量元素及张掖土壤所有微量元素均具有强烈的空间自相关性 ...
赵良菊 肖洪浪 郭天文 赖丽芳 杨文玉 包兴国
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Experimental study on the influencing factors of permeability of sand media [PDF]
The Darcy test is the primary method for determining the permeability of sand media. However, factors such as particle size and compaction of the sand medium, differences between the total dissolved solids (TDS) and the head of the water, and the test ...
Jiutan LIU +3 more
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土壤盐分和含水量的空间变异性及其CoKriging估值——以黄河三角洲地区典型地块为例
Shuitu Baochi Xuebao, 2006 以黄河三角洲地区典型地块为研究区，运用经典统计学和地统计学相结合的方法研究了不同深度土层盐分和含水量的空间变异特征。结果表明：研究区土壤盐分和含水量普遍较高，土壤表层积盐作用明显；各层土壤盐分均属于中等变异强度，土壤含水量除表层为中等变异强度外，其余各层为弱变异强度；受结构性因素和随机性因素的共同作用，各土层盐分和含水量均具有中等的空间相关性。对Kriging插值结果分析表明，研究区各土层盐分和含水量在一定的范围内均存在着空间上的相关性和变异性，表层土壤盐分和含水量的空间分布主要受微地形和气候条件的影响，
姚荣江, 杨劲松, 刘广明
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Distribution Characteristics, Ecological Risks, and Source Identification of Heavy Metals in Cultivated Land in Xingyang City [PDF]
The quality of arable land is closely related to people’s livelihoods, and heavy metals are one of the significant factors affecting arable land quality.
Xinlei ZHAO +3 more
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Shuitu Baochi Xuebao, 2020 于2018年4月至2019年3月在长沙地区典型樟树林收集降水、穿透水和相应的冠层信息，分析穿透水量的空间变异及穿透水稳定同位素的特征，旨在揭示林冠层水文过程，为林地水文生态系统的科学管理提供参考。结果表明：樟树林下总穿透水量为340.1 mm，占林外总降水量的71.2%；受观测点距树干距离和冠层叶面积指数等因素的综合影响，穿透水量具有较大的空间变异，且在时间变化上相对稳定。分析表明，研究区穿透水量的空间变异系数随降水量增加而减小，体现了降水特征对穿透水空间变异的重要影响；相对穿透水量而言 ...
戴军杰 +5 more
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Progress in developments and applications of the HYDRUS model and associated coupling model packages [PDF]
HYDRUS model is widely used in agricultural irrigation and pollution transport because it can comprehensively consider the movement of water, heat, and pollutants in the soil-plant-atmosphere system.
Bei ZHANG +5 more
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Submarine groundwater discharge and its impact on mangrove habitats in Dongzhaigang Area, Northeastern Hainan Island [PDF]
Submarine groundwater discharge (SGD) is a significant yet often overlooked pathway for material exchange between terrestrial and marine environments, delivering freshwater and nutrients to coastal ecosystems and influencing mangrove wetland health ...
Qinghua LI +5 more
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Methodology for identifying the damage state of sandstone using Mel-frequency cepstral coefficient of acoustic emission [PDF]
Rock mass structure rupture is an important factor that seriously restricts the construction and safe operation of underground space engineering projects such as mines, subways and tunnels.
Aleksei SOBOLEV +7 more
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Shuitu Baochi Xuebao, 2018 运用经典统计学和地统计学分析方法，探讨了江西省油菜种植区土壤碳氮磷生态化学计量特征的空间变异性及影响因素。结果表明：江西省油菜土壤有机碳（SOC）、全氮（TN）和全磷（TP）平均含量分别为16.99，1.44，0.50 g/kg，土壤C∶N、C∶P和N∶P平均值分别为12.28，38.31和3.27，土壤总体C∶N∶P为33.86∶2.88∶1，整体处于相对较低水平，表现出中等程度的变异性和空间自相关性，其空间变异特征受到结构性因素和随机性因素的共同影响，但受结构性因素影响更大。从空间分布规律看 ...
张晗 +5 more
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六盘山华北落叶松人工林土壤水分空间异质性的降雨前后变化及其影响因素
Shuitu Baochi Xuebao, 2016 为了阐明林冠叶面积指数、枯落物厚度等植被因子及降雨量影响下的林地土壤水分空间异质性变化规律，在宁夏六盘山香水河小流域选择了2个35 a华北落叶松典型坡面（东南坡A、南坡B），遵循空间格局分析的小支撑、多样点设计原则，结合所选坡面特征，利用线状样带取样法，测定了坡面上各样点的表层（0—20 cm）和亚表层（20—40 cm）土壤水分、林冠叶面积指数、枯落物层厚度、坡度及离开最近一棵树主干的距离，采用经典统计结合地统计学方法，分析了降雨前后土壤水分空间变异特征 ...
刘, 王彦辉, 邓秀秀, 徐丽宏
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