降雨侵蚀下西双版纳人工林土壤磷素迁移特征及驱动因子OA

Taking typical plantations in Xishuangbanna(12-year-old rubber regeneration forest,20-year-old mature rubber for-est,and 26-year-old Macadamia ternifolia forest)as the research objects,the runoff plot positioning observation system was used to quantitatively analyze the spatio-temporal migration characteristics of phosphorus in 0-20 cm and 20-40 cm soil layers,litters and runoff water,and to explore the characteristics and driving factors of soil phosphorus migration in the three plantations under rainfall erosion.The results showed that:(1)The soil total phosphorus content showed significant differences among forest types.The soil total phosphorus content of 12-year-old rubber regeneration forest(0.47 g·kg-1)was significantly higher than that of other forest types,and the total phosphorus migration amount was the least at the mid-dle slope position,which had the strongest effect on soil phosphorus conservation.(2)At the end of the rainy season(Oc-tober-November),the soil total phosphorus content of the three forest types increased significantly,which was caused by reduced erosion and phosphorus fixation.(3)The total phosphorus concentration in runoff water was extremely significantly positively correlated with soil total phosphorus content(P＜0.01),and significantly positively correlated with litter total phosphorus content(P＜0.05),indicating that phosphorus migration caused by runoff scouring carried not only phosphorus in soil but also phosphorus in litters,and surface runoff was an important driving factor for phosphorus migration.