Soil Fertility Index Based on Minimum Data Sets Using PCA Method

YANG Mei-hua;ZHAO Xiao-min;WANG Fang-dong;GUO Xi;XIE Wen;Key Laboratory of Poyang Lake Basin Agricultural Resources and Ecology of Jiangxi Province,Jiangxi Agricultural University;Nanchang Teachers College;Ganzhou Agricultural Science Research Institute;

red-soil regions of Jiangxi;;principal component analysis;;soil fertility index;;minimum data sets

Soil fertility evaluation is essential for agricultural production in red-soil regions of Jiangxi Province.At present,many methods are used to evaluate soil fertility using vastly different indicators.A small number of carefully chosen soil fertility indicators,when used in the soil fertility integrated indexes,would assist agriculture managers to better understand the soil fertility conditions of various agricultural systems.This study analyzes soil fertility indexes of three counties of Jiangxi Province by means of the integrated fertility indexes in combination with total data sets and minimum data sets using principal analysis.The correlations were analysed and Kappa values of classification were compared in soil fertility indexes based on total data sets and minimum data sets. The result shows that the correlation of soil fertility using total data sets and minimum data sets is0.92( ρ<0.01),the total accuracy in three classes is 88.75% and the Kappa is 0.82.It is concluded that using the method of soil fertility indexes and the minimum data sets can adequately represent the total fertility indexes and thus save time and cost.