黄土高原油松人工林地土壤水分物理性质研究

Improvement of soil hydro-physical proprties by artifical Robinia Pinus Tabulaeformis carr forests in the Loess Plateau

研究了黄土高原不同树龄的油松人工林地土壤物理特征及其变化规律。结果表明:土壤容重随树龄和土壤深度变化的差异极为显著;土壤总孔隙度、毛管孔隙度、非毛管孔隙度与树龄之间均无确定的变化规律,随土壤深度变化的差异极为显著;土壤最大持水量、毛管持水量和最小持水量随树龄的变化差异显著,随深度的变化差异极显著,因而树龄和土壤深度均可表征油松林地的持水能力。与撂荒地相比,油松人工林通过凋落物和土壤根系的作用可以降低土壤容重,并不同程度地改善土壤孔隙状况,增强土壤的持水能力。土壤总孔隙度、非毛管孔隙度、土壤最大持水量、毛管持水量和最小持水量分别增加了9.3%～36.3%、40%～232.8%、1%～103%、21.6%～46.2%、22.4%～43.7%,土壤毛管孔隙无明显增减规律。表明在黄土高原营造油松人工林有利于改善土壤水分物理状况。

The soil physical properties of manmade Pinus tabulaeformis forestland in the Loess Plateau at different forest ages had been studied. The results go as follows: Bulk density varies dramatically with tree ages and soil depths; total soil prosity,capillary prosity, non capillary prosity change irregularly with tree age, but greatly with soil depths; max soil moisture capacity,capillary capacity and moisture capacity change greatly with tree ages, and more greatly withs depth, so both tree ages and soil depthes could show the moisture capacity of Pinus tabulaeformis carr forestland. Compared with wastedland, Pinus tabulaeformis carr. Forestland soil bulk density could be reduce through the function of litters and root system, and to some degree, to improve soil prosity, to raise soil moisture capacity. Total prosity, non-capillary prosity, max moisture capacity, capillary capacity, moisture capacity rise respectively by 9.3%~36.3%, 40%~232.8%, 1%~103%, 21.6%~46.2%, 22.4%~43.7%, and soil capillary prosity changes little. These findings shows that it was favorable to improve soil hydro-physical properties by building plantation forests on the Losss Plateau.