杉木、马尾松人工林土壤物理性质及水分含量变化的研究

A STUDY ON SOIL-PHYSICAL PROPERTIES AND CHANGE OF SOIL MOISTURE CONTENT IN MAN-MADE FORESTS OF CUNNINGHAMIA LANCEOLATA AND PINUS MASSONIANA

1984～1988年,在江西省分宜县山下林场的亚热带人工杉木林和马尾松林中,对土壤的水分—物理性质及其水分含量的变化进行了测定,结果表明:本试验区土壤为重壤土,其水分—物理性质较差,有林地土壤含水量较无林地高,且变幅较小。土壤含水率与当地的主要气象要素(气温、空气湿度、降雨量、蒸发量)呈多元回归相关。据回归分析,杉木林土壤水分含量受气候变化影响的土层深度较浅,达0～20cm,而皆伐迹地受气候影响的土层较深,达0～40cm。

This study was made in the yellow-red earth of man-made forests Cunninghamia lanceolata and Finus massoniana in 1984-1988. There is a loam in soil texture. The depth of soil is thinner. The volume weight of soil ranges 0.78-1.35. The total porosity of soil is about 55%-77%, including capillarity porosity about 40%-50%.The coefficent of soil premeability 3.18-5.37mm/mun. The mean annual soil moisture content in 5 years is about 21% -32% of water. The soil moisture content in forests is more than that in the clear-cutting land, but the seasonal variation of soil moisture content in the forest is less than that in the clear-cutting land. The effect of climatical factors on soil moisture content is obvious. According to the mathematical statistics analysis, soil moisture(y) approximates precipitation (x1), air temperature (x2), air humidity (x3), air evaporation (x4) in polyromial regression, its equation is Y = a1x1+ a2x2 + a3x3 + a4x4+a5. According to the analysis of this polyromial regression, the depth of soil moisture content, obviously effected by climatical factors, reaches to 20 cm of the soil in the forests and reaches to 40 cm of the soil in the clear-cutting land.