Spatial variability of soil organic matter and pH and the correlation to available nutrients in the tea garden of southern Shaanxi.

【Objective】 The research studied the relationship between soil pH value,spatial distribution of organic matter and available nutrients for the tea garden accurate management.【Method】 Soil pH,organic matter,available N,available P,and available K of soil samples were measured in 99 tea gardens from 8 counties(Xixiang,Nanzheng,Mianxian,Chenggu,Ningqiang,Ziyang,Pingli,Shangnan) of southern shaanxi.The correlation between soil pH,organic matter and available nutrients was analysed.【Result】 The results showed that there were low contents of organic matter in tea gardens of southern Shaanxi,ranging from 0.96 to 43.34 g/kg,which couldn't meet the needs of high production;the pH values of soil ranging from 4.08 to 6.93 were suitable for the growth of tea.And the soil pH in Xixiang was higher than that of other 7 cocnties;a tendency of acidification was found in the soil of Ningqiang county and Mianxian county.The correlation between pH and organic matter,available N and available K was significantly or remarkabley negative,the correlation between pH and available P was significantly positive;the correlation between organic matter and available N,available K was significantly positive or extremely positive,the correlation between organic matter and available P was significantly negative.【Conclusion】 The use of reasonable organic fertilizer is benefitial for increasing the content of organic matter and available nutrition and improving the pH value.The pH valve,organic matter and available nutrition content is significantly or very significantly correlated.