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Serious soil erosion is one of the major issues threatening sustainable land use in semiarid areas, especially in the Loess Plateau of China. Understanding the effects of land use on soil ...
天津地区表土中蒽和芘的频率分布特征
2007/8/24
用频率分析、逐步聚类和最小二乘拟合等方法研究了天津地区表土中蒽和芘含量的频率分布特征。结果表明，两者都呈双峰分布，其中蒽的双峰特征尤为典型。可以用双高斯密度函数很好地拟合经对数变换的实际观测数据，证明天津地区蒽和芘都包括两个相对独立的对数正态分布总体。根据拟合频率密度函数求得的蒽的两个子总体几何均值分别为2.73±2.17 ng/g和26.52±1.55ng/g，芘则为11...
Terrestrial ecosystems represent the second largest carbon reservoir, and the C balance in terrestrial ecosystems can be directly impacted by human activities such as agricultural manageme...
Soil erodibility is an important index to evaluate the soil sensitivity to erosion. The research on soil erodibility is a crucial tache in understanding the mechanism of soil erosion. Soil...
The available soil water capacity (ASWC) is important for studying crop production, agro-ecological zoning, irrigation planning, and land cover changes. Laboratory determined data of ASWC ...
The Yangtze delta area is among the fastest developing areas in China. Here there are mega-cities like Shanghai, Nanjing and the attached urban areas of different sizes including those alo...
Based on regionalized variable theory, semivariograms of geo-statistics were used to research the spatial variation of soil properties quantitatively. The results showed that the semivario...
Under the framework of Chinese Soil Taxonomy, all the 14 established soil orders including Histosols, Anthrosols, Spodosols, Andisols, Ferralisols, Vertisols, Aridisols, Halosols, Gleyosol...
Based on Universal Soil Loss Equation and methods of mathematics model and GIS analysis, this study classified influence of precipitation, soil, topography and vegetation upon sensitivity ...
The present study aims the evaluation of bio-physical characteristics towards soil-water-vegetation stress and a rule is envisaged to assess the degree of temporal changes. The digital rul...
Lunan stone forest is a kind of typical karst in China, which is mainly developed under red soil. In the winter of 1999, three study sites were chosen in stone forest national park accordi...
Study on north boundary of subtropical zone in Funiu Mountain according to soil geochemistry
2007/8/24
The boundary between subtropical zone and temperate zone is not only important in physical geography, but also attractive in agricultural production. Seven soil profiles studied in this pa...
0.25 mm water stable aggregate content, the soil sheer strength and the soil erosion intensity were analyzed, which showed that the first and seventh years were the turning years of the so...
黑三角地区：适合于欧洲吗？
——黑三角地区空气质量的数字化研究
2007/8/24
“黑三角”地区包括波希米亚（原捷克斯洛伐克西部一个地区）北部、萨克森州（原民主德国一个州）南部以及下西里西亚（波兰、捷克和德国部分地区）的一部分。“黑三角”地区是中欧污染最严重的地区之一，主要因为硫和粉尘的排放量大而得名。经过80年代末的政治变革之后，该地区的空气质量已有很大改善。本文中，我们对萨克森地区和波希米亚北部的空气污染，尤其是二氧化硫、臭氧和气溶胶颗粒物所造成的空...