兰州大浪沟雨养生态试验示范区土壤养分状况研究

Soil nutrient status of rain-fed ecological experiment and demonstration zone at Dalanggou in Lanzhou

【目的】为了对兰州雨养生态区植被恢复与重建提供理论依据.【方法】以兰州市城关区青白石乡大浪沟为试验示范区,研究不同坡向(阴坡、半阳坡和阳坡)、不同土层深度(0~20、20~40、40~60、60~80cm)土壤养分的变化规律.【结果】0~80cm土层,土壤养分含量表聚现象明显,表现为,随着土层深度的增加而降低,且阴坡>半阳坡>阳坡.阴坡、半阳坡和阳坡的土壤有机质平均含量分别为:5.69、4.36、3.09g/kg;有效磷(P)平均含量分别为14.13、14.08、13.85mg/kg;速效钾(K)平均含量分别为:159.13、158.76、150.14mg/kg;水解氮(N)平均含量分别为:26.4、19.7、14.7mg/kg.【结论】大浪沟雨养生态试验示范区土壤养分含量总体偏低,土壤中速效K含量较高,有效P含量中等,有机质和水解N的含量极低,建议在植被恢复配置时,考虑耐瘠薄的品种,并适当施用有机肥料.

[Objective] To providing the basis of the theory for vegetation restoration and reconstruction of Lanzhou rain-fed ecological zones. [Method] Dalanggou of Qingbaishi Town in Lanzhou was taken as ex- periment and demonstration zone. The content of soil organic matter, available phosphorus （P）, available potassium （K）,and the hydrolysis nitrogen （N） were determined at different slopes and soil layer （0-20, 20-40, 40-60, 60-80 cm）. [Result] Soil nutrient content mostly accumulated in surface layer （0- 80 cm） obviously. The nutrient content reduced with soil depth increasing, and shady slope〉 half sunny slope〉 sunny slope. The average soil organic matter contents were 5.69,4. 36,3.09 g/kg at shady slope, half sunny slope,sunny slope. The average soil available P contents were 14. 13,14.08,13.85 mg/kg. The average soil available K contents were 159.13,158. 76,150. 14 mg/kg. The average hydrolysis N contents were 26.4,19.7,14. 7 mg/kg. [Conclusion] The soil nutrient contents are generally lower at rain-fed eco- logical experiment and demonstration zone of Dalanggou. The soil organic matter and hydrolysis N are ex- tremely low. It suggested that varieties of barren resistance should be considered in vegetation restoration and configuration, and while using some organic fertilizer appropriately.