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Our results indicate that defoliation and fertilisation, two common grassland perturbations, have contrasting impacts on root traits of grassland plant species, with direct and indirect short‐term consequences for a wide range of soil abiotic and biotic properties that underpin ecosystem functioning.
Yan Liu +2 more
wiley +1 more source
Nutrient Characteristics and Factors Influencing Surface Soil with Gully Erosion on Sloping Farmland for Low Hilly Terrain in Black Soil Area [PDF]
[Objective] The soil nutrient characteristics and influencing factors of surface soil gully erosion for low hilly terrain in the black soil area were studied in order to provide data and theoretical support for the rational use of land resources ...
He Xuyang +7 more
core +1 more source
Influence Mechanism of Ionic Interface Reaction on Soil Porosity [PDF]
[Objective] The changes in surface charge properties of soil particles and the net force between particles were analyzed, in order to elucidate the influence mechanism of particle interaction on pore conditions.
Ding Wuquan +3 more
core +1 more source
Erosive Rainfall Thresholds for Five Typical Soils in Water Erosion Region of China [PDF]
[Objective] The practical thresholds separating erosive from non-erosive rainfall events were determined to effectively reduce the workload of soil erosion prediction, and to provide references for regional soil erosion prevention.
Liu Baoyuan +3 more
core +1 more source
以贺兰山不同海拔植被下0—20,20—40 cm土层土壤为研究对象,分析不同粒径团聚体含量及团聚体稳定性随海拔升高的变化特征,探讨其与土壤理化性质之间的相关关系。结果表明:0—20 cm土层,0.25~0.053 mm团聚体为主要团聚体类型,随海拔增加,水稳性大团聚体(>0.25 mm)含量增加,高海拔>低海拔,较高含量的大团聚体和土壤养分是团聚体稳定的关键要素。
吴梦瑶 +6 more
doaj
土壤团聚体是保持土壤水分和土壤透性的基本单元.本综述的目的是通过围绕团聚体理论的讨论,明确影响团聚体形成的因素,为农田维护提出可靠的理论依据.首先总结了团聚体形成的主要理论,即Emerson的粘团理论、Edwards和Bremner的微团聚体理论和Oades 及Waters的团聚体分级构建理论,然后讨论了土壤有机质、可溶性阳离子和氧化铁、铝3个影响团聚体形成的主要因素,最后分析了团聚体破坏的机理和评价团聚体稳定性的主要方法,指出保持土壤颗粒的凝聚状态、增加各种形态的土壤有机质是增加土壤团聚性的主要措施.
赵京考, 刘作新, 韩永俊
doaj +2 more sources
应用Le Bissonnais法测定富铁土中团聚体的稳定性及其意义
土壤团聚体的数量和稳定性是衡量土壤抗蚀性和土壤质量的重要指标,应用LeBissonnais法对富铁土团聚体的稳定性和物理学机制进行了研究。结果表明,LeBissonnais法测定的团聚体平均重量直径(MWD)与常规湿筛法测定的>0.25mm团聚体含量、MWD和>2mm团聚体破坏率(PAD)呈极显著正相关。富铁土中5~2,2~1,1~0.5mm团聚体经快速湿润(FW)、慢速湿润(SW)和预湿后扰动(WS)处理后,稳定性团聚体的粒级分布随处理方式和初始团聚体大小的不同而不同;经FW处理后 ...
卢升高 竹蕾 郑晓萍
doaj +2 more sources
Comparasion study on the effects of mangrove wetland sediments on the sequestration of typical sulfonamides from the estuarine water [PDF]
作为陆地污染物进入海洋的屏障,红树林已然成为众多典型污染物汇聚的场所之一。近年来,海产养殖业的大肆兴起更是加重了抗生素在红树林区的直接污染。锁定态是控制土壤抗生素归宿的主要因素,具有环境存在时间长,危害大等特点,可通过再释放重回到环境中,对环境造成长期危害。对典型磺胺类在红树林群落沉积物中锁定能力的研究对于探索抗生素在红树林区的环境行为和红树林湿地抗生素污染控制及修复功能评估具有现实意义。本文选取了12种水产、禽畜及人用较为频繁的典型磺胺类药物,分别为磺胺甲噻二唑(sulfamethizole,SMT)、
张宇
core
Abstract Studies of lobbying typically look at the extent to which interest groups realize political goals on issues they actively lobby for. Little is known, however, about the extent to which interest groups attain their political goals without making an active lobbying effort.
Marcel Hanegraaff +2 more
wiley +1 more source
Gradient distributions of nitrogen and organic carbon in the soils from inland to tidal flat in the Yellow River Delta [PDF]
黄河三角洲是我国典型的通过黄河冲积泥沙填海造陆形成的近代沉积区。区域受到黄河冲积、沉积等自然过程和农业耕种熟化等人类活动的双重影响。本研究通过在黄河三角洲地区内陆到河口海湾不同距离采集典型土壤类型剖面发生层样品,探讨土壤有机碳、总氮等生源要素的空间分布规律,为阐明我国典型海岸带地区陆源碳、氮的输送及循环特征提供基础依据。研究结果表明,黄河三角洲内陆与河口地区呈现出完全不同的土壤碳、氮分布规律。表层土壤碳、氮含量在黄河沿岸及三角洲南部均表现出由陆向海逐级递减的空间分布特征 ...
李远 +4 more
core +1 more source

