关键词: 杀虫活性, 杀虫活性

Abstract:

In order to discuss the effects of vegetation restoration on soil nutrient status, the variation characteristics of soil nutrients among 5 different vegetation restoration types (natural grassland, enclosed grassland, abandoned land, land as returning farmland to woodland, fixed sandy land) on soil nutrient status were studied in southern edge of Mu Us sandy land. The results showed that: the influence of different vegetation restoration types on soil organic matter, total nitrogen, available nitrogen and available phosphorus were conspicuously different. The contents of soil organic matter, total nitrogen and available nitrogen in these lands (enclosed grassland, land as returning farmland to woodland and fixed sandy land) which were the combination of shrub and herb, were higher than in those lands (natural grassland and abandoned land) with mainly herb. But just the opposite, the contents of soil available phosphorus in these were lower than in those. The influence of vegetation on the surface 0-20 cm soil nutrient was greater than that on the deep 20-60 cm soil, also the soil nutrient was to surface enrichment under the action of vegetation. Planting the species (Caragana korshinskii) for converting cropland to forest could give full play to its root system characteristics, which could be helpful for improving deeper soil nutrient.