. 2006, 24(0602): 56-59.
VCCSW, short for Vegetation carrying capacity of soil water, is a key and scientific question for rational utilization of soil water and vegetation resource in the arid, semi-arid and semi-humidy region. Field study of density and plant growth, soil water supply and consumption is experimental base for determing vegetation carrying capacity of soil water. The field experiment was conducted in the shrubland having 16-years old artificial Caragana forest in the semi-arid region of Loess plateau to determining the value of VCCSW. Experimental density includes 8 700, 7 100, 5 100, 3 200, 1 600 clumps perhectare. The results showed as following: The term vegetation carrying capacity of soil water can be defined as the ability of soil water to carry vegetation. The limit is the largest density soil water keep plants grow and develop healthily on an annual basis under special conditions. Although the brush root penetrates to a depth of more than 500 cm, most of the root mainly distributed in ...更多the upper 150 cm soil, the relationship between root and depth is exponential function. The largest depth of rain penetration is from 170 cm in 2002 to 270cm in 2004. The root soil from which plant roots take and utilize water mainly is the soil layers from 0 to 270 cm soil layer. The relationship between soil water and plant growth can be divided into four stages. The relationship between density and productivity of Caragana forest or the amount of soil water supply in the shrubland is linear, the relationship between density and the amount of soil water consumption in the shrubland is parabola. The value of soil water's carrying capacity is 8 115 clumps per hectare. The best use orientation of perennial Caragana forest is to conserve soil and water and improving environment.
