Spatial variability of soil organic matter and pH and the correlation to available nutrients in the tea garden of southern Shaanxi | 陕南茶园土壤有机质和pH值空间变异及其与速效养分的相关性

chinois. 研究陕南茶园土壤pH值和有机质的空间变异及其与土壤速效养分的相关性，为陕南茶园土壤精准化管理提供依据。采集陕南8个县（西乡县、南郑县、勉县、城固县、宁强县、紫阳县、平利县和商南县）99个茶园土壤样品，对其pH值、有机质和速效N、P、K含量进行测定，分析土壤pH值、有机质含量与速效养分含量的相关性。陕南茶园土壤有机质含量总体较低，为0.96～43.34 g/kg，未达到优质高产茶园的要求；pH为4.08～6.93，均能满足茶叶生长的基本土壤酸碱度条件。西乡县茶园土壤pH值显著高于其他7个县（P＜0.05），宁强县和勉县土壤pH值有减小的趋势。pH值与有机质含量、速效N含量、速效K含量呈显著负相关或极显著负相关，与速效P含量呈显著正相关；有机质含量与速效N和速效K含量呈显著或极显著正相关，与速效P含量呈极显著负相关。陕南茶园应合理施用有机肥，以增加土壤有机质和速效养分含量，改善土壤酸碱度。陕南茶园土壤有机质含量、pH值与土壤速效养分含量之间相关性达到显著或极显著水平。土壤有机质含量和pH值影响着土壤速效养分的含量。

anglais. The research studied the relationship between soil pH value, spatial distribution of organic matter and available nutrients for the tea garden accurate management. 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. 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 counties; 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. 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.