冀西北高原不同植被的土壤水分动态变化研究

冀西北高原为高寒半干旱地区,降水是此地区土壤水分的唯一给源,研究土壤水分的动态变化对高效利用降雨有至关重要的作用。研究采用定点观测的方法,对不同植被土壤含水量的动态变化进行了比较研究。结果表明,3种植被生长期内不同土层土壤水分变化存在差异。生长前期,3种植被0￣30cm土层土壤含水量,农田耕翻地最高,水分条件最好,人工草地与退耕还林地互有高低,30￣60cm土层退耕还林地最高,人工草地最少。生长前期,农田耕翻地表层土壤水分较好,能满足春季作物生长要求。生长中期,0￣30cm土层农田耕翻地最低,人工草地与退耕还林地互有高低。30￣60cm土层农田耕翻地最高,人工草地最低。生长后期,0￣60cm土层农田耕翻地土壤含水量最高;人工草地土壤含水量与退耕还林地相比较,0￣40cm土层差异不大,40￣60cm土层退耕还林地高于人工草地。

Study on Dynamic Change of Soil Water to Different Vegetation in Northwest Plateau of Hebei Province

Experiments were carried out to study on dynamic change of soil water to different Vegetation in northwest plateau of Hebei Province. The climate character in this area is cold and semiarid. The only source of soil water is precipitation, study change of soil water is very important for soil water use efficiency. The result show: there is difference of soil water change to different vegetation. In early stages of growth, soil moisture is the highest in plough field than in converting farmland to forest field and in meadow field in 0~30cm depth; In 30~60cm depth, soil moisture is the highest in converting farmland to forest field, the second is in plough field, the least is in meadow field. In middle stages of growth, soil moisture is the least in plough field in 0~30cm depth; soil moisture of plough field is the highest, the second is in converting farmland to forest field, the least is in meadow field. In last stages of growth, soil moisture is the highest in plough field than in converting farmland to forest field and meadow field; Comparing with soil moisture of converting farmland to forest field and meadow field, soil moisture is not marked in 0~40cm depth; but in 40~60cm depth, soil moisture of converting farmland to forest field is higher than meadow field.