关键词: 滇东南峰林湖盆区, 土壤理化性质, 土壤水文结构功能

Abstract: In order to investigate the soil physical and chemical characteristics in different vegetation restoring stages during the process of returning farmland to forest in Karst area, this paper set up sample plots in different slope positions at the studying area: Slope land, Yunnan pine plantation (downhill), secondary forest (medium slope) and limestone shrub (uphill ). Soil physical and chemical properties were investigated by means of field sampling combined with indoor analysis. Pearson relativity analysis and principal component analysis were carried out. Finally, the function model of soil hydrological structure was used to evaluate the soil hydrological structure of the Puzhehei restoration vegetation. Results showed that the soil porosity and water holding capacity in the studying areas were mainly secondary forest >Yunnan pine >limestone shrub >sloping farmland. The organic matter, total nitrogen, total phosphorus, total potassium and other elements of Pinus yunnanensis plantation and secondary forest were higher, and their pH was lower. Correlation analysis showed that soil moisture content, organic matter, total nitrogen, total potassium, exchangeable magnesium and other physical and chemical properties of soil were strongly correlated, and the main factors of maintaining soil physical and chemical properties in Karst area. Principal component analysis showed that soil total porosity, non capillary porosity, water content, organic matter, total phosphorus, exchangeable magnesium, exchangeable calcium and pH were the key factors of soil physical and chemical properties, and the carriers of nutrient cycling and flow. The calculation results of soil hydrological structure function index indicated that secondary forest (0.68%) > Yunnan pine forest (0.43%) > limestone shrub (0.26%).

Key words: Southeast Yunnan peak forest-lake basin, soil physio-chemical properties, soil hydro-structure function