Investigation and evaluation of soil nutrients of walnut nonwood forestland in Yijun County

ZHAO Ying-cui;GENG Zeng-chao;CHEN Jin-hai;LIN Yun;College of Resources and Environment,Northwest A&F University,Key Laboratory for Plant Nutrient and Agricultural Environment in Northwest China,Ministry of Agriculture;The Walnut office of Yijun County;

walnut forestland;;soil nutrients;;Nemerow index;;soil fertility evaluation;;Yijun County

The soil samples in 0 ~ 25 cm layers were collected,and pH value,organic matter content,total N,total P,total K,alkali-hydrolysable N content,available P content,and available K content were measured,this study were conducted to investigate and evaluate the nutrients of soil of 10 towns of Yijun County using the improved Nemerow index method. As a whole,the soil fertility of each village and town was moderate in Yijun County. Wuli town,Leiyuan town,Chengguan town,Xicun town,Peng town,Qipan town,Yunmeng town,Taian town and Kuquan town had a soil fertility coefficients between 0. 91 ~ 1. 19(0. 9 ~ 1. 8),indicating a moderate fertility level. However,the poor soil fertility level of Yaosheng town was reflected by the soil fertility coefficient of 0. 89(< 0. 9). The main limiting factors in this region were total N and available P. In summary,problems facing Yijun County in terms of soils are low level of nutrient content,uneven distribution of alkali-hydrolysable N and available K,inadequate amount of total N,total P and available P,and high pH value,implying a larger space of the improvement of soil fertility.