关键词: 土壤水分, 植树造林, 地形, 兰州南北两山, 黄土高原

Abstract: Against different slope direction and tree species we have conducted long-term monitoring on soil water in some important afforestation models on the Loess Plateau: terrace, level-gouge, fish-scale pit, and mesa and so on. The soil water content was measured once ten days by neutron probe. Some results have been got as follows: (1) Before seed germination, the soil water of shaded hillside without the effects of plants was more than that of sunny hillside；In same direction slope, the soil water condition of the southern mountains was better than that of the northern. (2) After middle April, affected by plant growth the soil water of the northern mountains was more than that of the southern, but the varying of soil water in the southern mountains was faster than that in the northern. (3)The afforestation models-fish-scale pit and level-gouge had function of water-collecting and water-maintaining, but the function was related to rainfall; the surface area of level-gouge was bigger, so the effect of water-collecting would be better if overlaid with plastic film. (4) The soil water of terrace on shaded hillside was increasing from outside to inside.

Key words: soil water, afforestation, terrain, southern and northern mountains in Lanzhou city, the Loess Plateau