喀斯特地区黄壤土壤水库蓄存能力及分形估算

以重庆市黔江区喀斯特地区3种典型黄壤为研究对象,分析了其土壤水库蓄存能力,通过构建2种土壤粒径分形模型对3种土壤的土壤水库蓄存能力做了推导预测。结果表明,喀斯特地区黄壤土壤水库蓄存能力受到土壤密度、有机质、土壤颗粒和土层厚度的共同作用;以土粒粒径与颗粒数量关系求得的土壤分形维数(D1),以及以土粒粒径与颗粒质量关系求得的土壤分形维数(D2),可以用来推求喀斯特地区黄壤的田间持水率和萎蔫系数;利用土壤粒径分布进行的土壤水库蓄存能力预测,萎蔫系数的预测情况较田间持水率较差,这也造成了无效水库容与有效水库容预测精度比贮水库容和通透库容的预测低。

Water Retention Capability of Yellow Soil Reservoir and Its Fractal Dimension Estimation in the Karst Area

Choosing three kinds of yellow soil in Qianjiang district of Chongqing as the research objects,this paper discussed the basic characteristics of their soil reservoir,and figured out the water retention capacity of soil reservoir based on soil fractal dimension calculated by soil particle size distribution.The results showed that,①the water retention capacity of soil reservoir of the yellow soil in karst area was influenced by bulk density,organic matter,soil particles,as well as the soil depth.②Field capacity,wilting coefficient and the water retention capacity of soil reservoir of tested soil could be estimated by the fractal dimension(D1) based on the relationship between soil particle size and soil particle number and the fractal dimension(D2) based on the relationship between soil particle size and soil particle weight,however,much poorer result in the deeper soil.③The prediction of wilting coefficient was poorer than that of the field capacity,resulting in the same poorer estimation in available water storage capacity and non-available water storage capacity.