黄土高原沟壑区果园还耕对土壤水分的影响

在黄土高原沟壑区王东沟小流域,在塬面、梁地和坡地三种地貌类型上,分别选取了盛果期果园、老果园和退耕还田等3种土地利用与管理方式,测定土壤0～400 cm(塬面0～600 c m)水分含量分布,研究果园的利用管理方式变化对土壤剖面中水分含量变化的影响.结果表明,梁地和坡地上,盛果期果园、老果园土壤水分含量均接近作物凋萎湿度(10%);塬面上,盛果期果园、老果园土壤水分含量为15%.退果4年的耕地、坡地0～400 cm土层土壤储水量显著增加,梁地和塬面虽有增加但与老果园相比,剖面储水量并没有达到显著水平;退果4年耕地、坡地和梁地剖面中的60～140 cm和220～400 cm含水量提高最显著,塬面上22 0～600 cm土层中水分提高显著.

Influence of orchard planting-life and returned to cultivated land on soil moisture content in typical gully region of the Loess Plateau

The change of land use and land management takes c rucial roles on environment of soil moisture content. The various land use and m anagement were collected, such as peak period, aged orchard and cultivated land from returning orchard on three terrains, i.e. tableland, slopeland and ridgelan d, to analyze the effect of change of land-use and management on soil moisture content in soil profile in the form of measuring distribution of soil moisture i n the 0～400 cm (0～600 cm on tableland). The results show that: on the slopelan d and ridgeland, soil moisture content of peak orchard and aged orchard is close to crop wilting humidity, approximately equalled to 10%. On tableland, soil moi sture in peak orchard and aged orchard is about 15%. For cultivated land aged fo ur years after returning orchard, the water storage in 0～400 cm on slopeland in creases significantly. On tableland and ridgeland, compared to aged orchard the soil water storage in profile can not reach significant level although it increa ses; and for cultivated land aged four years after returning orchard, the soil m oisture in 60～140 cm and 220～400 cm in profile on slopeland and ridgeland incr ease significantly, compared to 220～600 cm on tableland.