纳板河流域不同植被类型下土壤肥力综合评价

Comprehensive evaluation of soil fertility under different vegetation types in the Naban River Basin

为了解不同植被类型土壤肥力差异,通过检测土壤自然含水率、土壤容重、pH、有机质、全氮、全磷、全钾和速效钾等土壤肥力指标,运用主成分分析对西双版纳纳板河流域20 a茶树林、甘蔗地、5 a橡胶林、8 a橡胶林、15—20 a橡胶林、火龙果地和香蕉地等不同植被类型土壤肥力进行评价。结果表明:纳板河流域土壤自然含水率变异系数除8 a橡胶林和15—20 a橡胶林外均属于中等强度变异;土壤容重除甘蔗地变异系数为18.12%,属中等强度变异,其他植被类型变异系数均低于10%,属弱变异;土壤pH变异系数均属于弱变异;有机质变异系数除香蕉地外均属于中等强度变异;全氮变异系数也均属于中等强度变异;全磷变异系数除甘蔗地和火龙果地均属于弱变异;甘蔗地、5 a橡胶林和香蕉地全钾变异系数属于弱变异,其他植被类型均属于中等强度变异;而速效钾变异系数均属于中等强度变异。通过对纳板河流域不同植被类型土壤肥力研究,将其肥力排序为:甘蔗地>20 a茶树林>5 a橡胶林>香蕉地>火龙果地>15—20 a橡胶林>8 a橡胶林。

This study evaluated the soil fertility under various vegetation types in Naban River Basin,Xishuangbanna by measuring indicators like the natural moisture content of soil, soil bulk density, pH, organic matter,total nitrogen,total phosphorus,total potassium and rapidly available potassium,etc. Principal component analysis was used to treat soil under different vegetations including 20 a tea plant and sugarcane land,5 a rubber plantation,8 a rubber plantation, 15 —20 a rubber plantation, pitaya land and banana land in this region. The results showed that the variation coefficient of soil natural moisture content in the Naban River Basin was of moderate intensity except 8 a rubber plantation and 15 —20 a rubber plantation, and the variation coefficients of soil bulk density for the sugarcane field, was 18. 12%, showing moderate intensity variation, while other vegetation types were lower than 10%, of weak variation. The variation coefficient of organic matter showed variation of medium intensity except banana. And the total nitrogen variation coefficient showed also a variation of medium intensity; Total phosphorus variation coefficient was of weak variation except sugarcane land and pitaya land. Total potassium of the sugarcane land,5 a rubber plantation and banana land was of weak variation,while others were of medium intensity variation. The rapidly available potassium variation coefficient was medium intensity variation. Based on the above statistics, it was found that the soil fertilities under these vegetation types could be resorted in the following descending order：sugarcane land,20 a tea plant,5 a rubber plantation,banana land,pitaya land, 15 —20 a rubber plantation,8 a rubber plantation.