滇中不同植被恢复模式下土壤肥力变化趋势研究

采用定点监测方法,对滇中不同植被恢复模式下的土壤理化性质进行定期观测和土壤肥力变化趋势分析,结果表明:退耕还林期间,随着植被生长量的提高,土壤容重逐渐降低,土壤孔隙度则随之增加,土壤肥力逐渐提高,说明植被恢复能有效改良土壤并提高土壤肥力,且随着林木生长量的增加,土壤肥力的增加趋势更加显著.退耕还林9 a后,不同植被恢复模式下的土壤肥力依次为:云南松+旱冬瓜林>银荆林>川滇桤木林>旱冬瓜林>墨西哥柏林>云南松林,说明由于树种不同导致土壤改良作用差异,针阔混交林的土壤改良作用最好,其次是阔叶林,建议在退耕还林和中低产林等工程中多营建针阔混交林和阔叶林.

Study on Change Trends of Soil Fertility under Different Vegetation Recovery Modes in Central Yunnan Province

A study on the soil physical-chemical property under different vegetation recovery modes in central Yunnan province was conducted by fixed observation. The results indicated that the growth of vegetation was improved, soil bulk density gradually reduced and soil porosity increased, soil fertility increased during returning farmland to forest. It showed that vegetation recovery can effectively soil property and soil fertility, and as forest growth volume increased, the trend of soil fertility increase was more significant. After 9-year of returning farmland to forest, the level of soil fertility under different vegetation recovery modes was as the sequence of Pinus yunnanensis+Alnus nepalensis mixed forest>Acacia dealbara forest>Alnus ferdinandi-coburgii forest>Alnus nepalensis forest>Cupressus lusitanica forest>Pinus yunnanensis forest. The needle and broad-leaved mixed forest were the best in soil improvement, followed by broad-leaved forests. It is recommended that the needle and broad-leaved mixed forest and broadleaf forest should be established in returning farmland to forest and low-yield forest reconstruction project.