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对珠江源头区占马地小流域灌木林地、疏林地、耕地及荒草地4类不同用地的土壤含水量、理化性状、土壤侵蚀特性等进行测定分析,结果表明:1)在土层60 cm深度范围内,随着土层的加深,灌木林地和疏林地的土壤水分含量呈下降趋势,而耕地和荒草地则呈上升趋势。2)土壤在持水能力、通透性能等方面排列顺序是灌木林地>荒草地>疏林地>耕地;土壤有机质含量以荒草地最高,为2.34%,分别是灌木林地、疏林地和耕地的1.08、1.89和3.46倍;全氮含量顺序是荒草地>灌木林地>疏林地>耕地;全磷和全钾含量顺序是疏林地>荒草地>灌木林地>耕地。3)不同用地的初渗速率、稳渗速率与渗透系数均为灌木林地最大,荒草地最小,灌木林地的稳渗速率、渗透系数分别是耕地、疏林地、荒草地的1.142、.06和2.7倍。4)不同用地的土壤最大持水量,在0~20 cm土层,排列顺序为耕地>灌木林地>疏林地>荒草地;在20~60 cm土层,则为疏林地>灌木林地>荒草地>耕地。5)在坡度相同的情况下,不同用地的降雨产流时间为荒草地>疏林地>灌木林地>耕地;地表径流量为荒草地>疏林地>灌木林地>耕地;土壤侵蚀量以耕地最大,分别是灌木林地、疏林地和荒草地的2.51、2.26和1.32倍。研究结果可为珠江源头区土地合理利用提供理论依据。
The soil water content, physico-chemical characteristics and soil erosion characteristics of four types of shrub land, sparse woodland, cultivated land and weedland in the headwaters of the Pearl River were measured and analyzed. The results showed that: 1) Within the range, with the deepening of the soil layer, the soil moisture content of shrub land and sparse woodland decreased while that of cultivated land and wild grassland increased. 2) The order of soil water holding capacity and permeability is shrub land> wild grassland> sparse land> farmland; soil organic matter content is the highest in grassland, 2.34%, which is 1.08 of shrub land, sparse land and farmland respectively , 1.89 and 3.46 times respectively. The order of total nitrogen was wild grassland> shrub land> sparse forest land> cultivated land. The order of total phosphorus and total potassium was sparse forest> wild grassland> shrub land> farmland. 3) The initial infiltration rate, steady infiltration rate and permeability coefficient of different land use are the largest in shrub land, the smallest in grassland, the steady infiltration rate and the permeability coefficient of shrub land are 1.142, .06 and 2.7 in arable land, sparse forest and grassland respectively Times 4) The maximum water holding capacity of soil in different land use ranged from arable land> shrub land> sparse woodland> wild grassland at 0 ~ 20 cm soil layer; sparse woodland> shrub land> wild grassland at 20 ~ 60 cm soil layer > Cultivated land. 5) Under the same slope condition, the runoff and runoff time of different land use areas are wild grassland> sparse woodland> shrub land> farmland; surface runoff is wild grassland> sparse woodland> shrub land> farmland; They are 2.51, 2.26 and 1.32 times of shrubland, sparse forest and wasteland respectively. The results can provide a theoretical basis for the rational use of land in the headwaters of the Pearl River.