广西南宁马占相思人工林土壤肥力变化的研究

对不同年龄阶段(4、7和11年)马占相思人工林土壤物理性质、化学性质和生物化学性质(土壤酶活性)进行研究,结果表明:随着林龄增加,林地土壤水稳性团聚体、非毛管孔隙、毛管孔隙、最大持水量、毛管持水量和田间持水量均呈增大趋势,土壤腐殖质(包括胡敏酸和富里酸)、全氮、水解氮、全磷、速效磷和土壤过氧化氢酶、蛋白酶、脲酶、酸性磷酸酶也有相同的变化规律,土壤结构破坏率和密度则呈下降趋势.土壤酶活性与土壤养分间呈现显著相关关系,可作为评价土壤肥力的指标.

Studies on Soil Fertility Change in Acacia mangium Plantation in Nanning, Guangxi

Due to adaptive to the infertile habitat,Acacia mangium is widely planted as pioneer species in tropical and south subtropical regions in China.In order to understand the soil fertilities changes in A.mangium plantation,the soil physical and chemical properties and enzyme activities with different age classes were studied.The results showed that with the stand age increases,soil water-stable aggregate,non-capillary porosity,capillary porosity,maximum moisture capacity,minimum moisture capacity and field moisture capacity of A.mangium plantation increased,there was similar tendency changes on the content of soil humus(humic acid and fulvic acid),total N,hydrolyzable N,total P,available P,and the activities of catalase,urease,protease and acid phosphatase,but the rate of structure destroy and density of soil were in reverse trend.Enzyme activities in soil were closed related to soil fertilities,it could also be used as an evaluation index of soil fertility.Therefore,the A.mangium plantation could significantly improve soil structure and moisture condition,improve the content of soil organic matter and nutrients,prevent soil degradation and protect eco-environment,which was advantageous to the sustainable development of forestry.