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用水头法、压力板法和水汽压法测定不同土水势下原状土的水分特征曲线;以多项式分段逼近法求得水分分布曲线;用水平土柱法测定水分扩散率.结果表明,土壤孔隙和质地状况是决定水分状况的主要因子,持水和导水二者密切相关.壤质草甸土各层能较多地保持可利用水分,且有适中的导水力;棕壤有致密的犁底层可能对水分运移产生阻滞作用;砂质草甸土30cm以下砂层保水能力差,通透性过大,有漏水漏肥的危险.
The water characteristic curve of undisturbed soil under different soil-water potentials was determined by water head method, pressure plate method and vapor pressure method. The water distribution curve was obtained by polynomial piecewise approximation method and the water diffusivity was measured by horizontal soil column method.The results showed that the soil porosity And texture are the main factors to determine the status of water, water and water conduction are closely related to both the loamy meadow soil layers to maintain more available water, and have a moderate hydraulic conductivity; brown soil with a compact plow The bottom layer may have a retarding effect on water migration; Sandy sand below 30cm in sandy meadow soil has poor water retention capacity and permeability, which may lead to water leakage and fertilizer leakage.