不同土地利用方式对华西雨屏区坡地土壤肥力及土壤酶活性的影响

利用坡面径流场,采用修正后的内梅罗指数法,通过对华西雨屏区坡地不同土地利用方式、不同坡度的自然生草、黑麦草和灌木的土壤肥力及土壤酶活性影响的研究,结果表明:5°坡度,自然生草土壤pH值、有机质和全氮含量小于黑麦草,而土壤全磷、全钾、碱解氮、有效磷和速效钾含量均高于黑麦草.15°坡度,土壤pH值大小顺序为灌木黑麦草自然生草;全磷和有效磷含量大小顺序为灌木自然生草黑麦草;有机质、全氮、全钾、碱解氮和速效钾含量大小顺序为自然生草灌木黑麦草.土壤综合肥力系数大小为5°自然生草5°黑麦草、15°灌木15°自然生草15°黑麦草,且五种土地利用方式的土壤肥力均为一般,说明具有生物多样性的自然生草对华西雨屏区表层土壤的肥力提高效果优于黑麦草,而木本植物对华西雨屏区表层土壤的肥力提高效果最好.

Effects of different land use patterns on soil fertility and Soil Enzyme Activity of sloping fields in Rainy Screen Area of West China

Based on the observation of slope runoff fields, the revised inside mei luo index method is adopted to do study on the effects of different land use patterns and different slopes of natural grass, perennial ryegrass and shrubs on the soil fertility and soil enzyme activity in the rainy screen area of West China. The results showed that in the case of 5° slope runoff fields, natural grass soil pH, organic matter and total nitrogen content are less than the perennial ryegrass, and soil total phosphorus, total potassium, alkali solution nitrogen, available phosphorus and available potassium content higher than that of perennial ryegrass. In the case of 15° slope runoff field, soil pH value size order for shrubs is higher than perennial ryegrass and perennial ryegrass is higher than natural grass; Total phosphorus and effective phosphorus content size order for shrubs is higher than natural grass and natural grass is higher than perennial ryegrass. The organic matter, total nitrogen, total potassium, alkali solution nitrogen, rapidly-available potassium content size order for natural grass 〉 shrub 〉 perennial ryegrass. Coefficient of soil integrated fertility of size 5° natural born grass 〉 5° ryegrass 15°, 15° shrubs 〉 natural grass 〉 15° ryegrass, and the soil fertility of five kinds of land use pattern is the same. It illustrates in the rainy screen area of West China the effect of surface soil fertility of natural grass with biodiversity is better than that of perennial ryegrass area, and woody plants is the best.