摘要
By comparison of several kinds stands, effect of vegetation and land use on the surface soil was investigated in Wutal Mountains of Shanxi Province. The result shows that larch (Larix principis-rupprechtii) and birch stands (Betula platyphylla) have more favourable influence on the properties of surface soil than pine (Pinus tabulaeformis) plantation and mixed plantation of pine and poplar (Populus cathayana). Since deciduous species forest had more annual litter and higher nutrient contents in the litter, thus much more nutrient returned to soil. Mixed planting of pine and poplar could largely improve the soil fertility because litter of poplar is greater in amount and decomposes within 1≈2a. The shrub lands contained high nutrient contents in leaves and relatively few human intervention, much of nutrient accumulates in the soil over a long period, resulting in higher nutrient contents in shrub land soil than that in pine plantation soil. Some of them, such as rose (Rosa bella), spiraea (Spiraea trilobata), ostryopsis (Ostryopsis davidiana) and bushclover (Lespedeza bicolor) dominant stands, have even higher nutrient status than larch and birch stands. Land-use could significantly change the soil fertility. Soil organic matter and nutrient contents decreased after shrub stand was cultivted as cropland, but increased largely to the pre-cultivated level during following period. It is recommended that larch is the optimum species in the afforestation activities in this area. Natural birch stand should be protected from further damage. Cultivation of shrub land should be stopped. The development and comprehensive utilization of shrub resources should be strengthened by the way of alternative cultivation.
