贵州中部喀斯特地区黄壤持水性能的研究

Study on Water Holding Capacity of Yellow Soil in Karst Area of Central Guizhou

在贵州中部采取0～1000cm土层的黄壤样品，分析了土壤基本理化性质，测定了土壤水分特征曲线，采用数理统计方法对数据进行了整理与分析。贵州中部低山丘陵区黄壤粘粒含量高。〈0．01mm颗粒含量806．23～686.2g／kg，〈0．001mm粒径颗粒含量651．05～263．57g／kg，粘粒含量高．犁底层透水性差，不利于降雨入渗。黄壤的持水量高，有效水的范围极窄10～100cm土层总库容5515．3m^3／hm^2。贮水库容4094．1m^3／hm^2，有效水库容仅9．69％，其比例较广州赤红壤、华北潮土和东北黑土低35．65，43．17和41．19个百分点；黄壤的通透库容小，不利于水分的上、下运行。

Yellow soil samples with a profile from 0 to 100 cm depth had been collected in hills of central Guizhou province and their basic properties had been tested as well as soil water characteristic curve. All the data have been analyzed by means of mathematic processing method of DPS. The yellow soil is low in clay particle content with a 〈0.01 mm grain range from 806.23 g/kg to 686.2 g/kg and a〈0. 001 mm grain content from 651.05 g/kg to 263.57 g/kg, while theplousole has an even higher clay particle content, which leads to an even lower infiltration rate of precipitation. Yellow soil has a high content in water holding capacity, however it is narrow in available water ranges. The total volumetric capacity of yellow soil in 0-100 cm soil layer depth amounts to 5 515.3 ma/ hm^2 and its water-storage volumetric capacity totals up to 4 094.1 m^3/hm^2 with only 9.69 percent as available water-storage volumetric capacity. The ratio of available water-storage volumetric capacity in yellow soil is 35.65, 43.17 and 41.19 percent lower than those of the latored soil in Guangzhou, the Chao soil in north China and the phaeozem in northeast China, respectively. The transmission volumetric capacity of yellow soil is limited and is unfavorable to both upwards and downwards movement of soil water.