Effects of Different Preceding Crops on Soil Fertility of Plukenetia volubilis L.
In order to reveal the effect of different cultivation patterns on soil nutrition of the Plukenetia volubilis L.plantation,five cultivation patterns(Tea-P.volubilis,Rice-P.volubilis,Banana-P.volubilis,Maize-P.volubilis and the control group of P.volubilis) were selected in Puwen Town of Xishuangbanna,Yunnan Province,to analyze soil characterization,including pH,electrical conductivity(EC),organic matter,total nitrogen,total phosphorus,total potassium and mineral elements in rhizosphere and bulk soil.The results showed that the pH,electrical conductivity and total dissolved solids in rhizosphere and bulk soil of four rotations were significantly different from the control group of P.volubilis.Total Mn,Fe,Zn and Cu concentrations in soil were under the world average level and the contents of heavy mental(Zn and Cu) were below 1.Soil fertility of different cultivation patterns was in this order,Maize-P.volubilis Tea-P.volubilis Banana-P.volubilis Rice-P.volubilis Free-P.volubilis,according to the comprehensive analysis of the contents of organic matter,total nitrogen,total phosphorus and total potassium.Above all,it was suggested that Maize-P.volubilis and Tea-P.volubilis patterns were better.