新疆塔里木盆地东南缘红枣种植园土壤肥力评价

Evaluation of Soil Comprehensive Fertility of Jujube Plantation in the Southeastern Margin of the Tarim Basin,Xinjiang

【目的】为探究新疆塔里木盆地东南缘红枣种植园土壤肥力情况及主控因素。【方法】采集表层土壤样品66组,测定土壤pH值、阳离子交换量(CEC)、有机质、全氮、全磷、全钾等指标,做相关分析,依据全国第二次土壤普查及专家经验,利用改进内梅罗综合指数法对研究区土壤肥力进行评价。【结果】研究区土壤均为强碱性土壤,土壤CEC处于较低水平,土壤有机质和全氮含量属于中下水平,土壤全磷和全钾含量较为适宜;研究区总体土壤pH值呈弱变异性,总体土壤有机质、CEC、全氮、全磷和全钾为中等变异,其中土壤CEC、全氮和全磷受外界影响比较相似;土壤pH值与全磷成显著负相关,有机质、CEC与全氮的含量呈极显著正相关,有机质和CEC也成极显著正相关;根据土壤综合肥力评价,研究区土壤肥力主要以Ⅲ级为主,评价未得到土壤pH值、有机质、CEC和全氮的分肥力系数(Fi)达到肥沃水平,其中全氮分肥力系数(Fi)均为最小。【结论】依据改进内梅罗综合肥力评价结果得出塔里木盆地东南缘红枣种植园土壤综合肥力为中等水平,确定全氮是限制土壤综合肥力的主要因子,依据此结果选择合适的肥料、采取适宜的土壤养分管理,以提升土壤养分含量、提高土壤保水和保肥能力、改良土壤酸碱度,进而改善土壤肥力、提高土壤质量。

[Objective]The aim was to explore the soil fertility and main controlling factors of jujube plantation in the southeastern margin of Tarim Basin,Xinjiang.[Method]66 groups of topsoil samples were collected and soil pH,cation exchange capacity(CEC),organic matter,total nitrogen,total phosphorus,total potassium and other indicators were determined,and the correlation analysis was performed.Based on the second national soil census and expert experience,the soil fertility in the study area was evaluated by the improved Nemero comprehensive index method.[Result]The soil in the study area was strongly alkaline soil,the soil CEC was at a low level,the soil organic matter and total nitrogen content were at the middle and lower levels,and the soil total phosphorus and total potassium contents were more suitable.The overall soil pH value in the study area was weakly variable,and the overall soil organic matter,CEC,total nitrogen,total phosphorus and total potassium were moderately variable.Among them,soil CEC,total nitrogen and total phosphorus were similarly affected by the outside world.Soil pH was significantly negatively correlated with total phosphorus,organic matter and CEC were significantly positively correlated with total nitrogen content,and organic matter and CEC were also significantly positively correlated.According to the evaluation of soil comprehensive fertility,the soil fertility in the study area was mainly grade III,and the fertility coefficients(Fi)of soil pH,organic matter,CEC and total nitrogen did not reach the fertile level,among which the total nitrogen fertility coefficient(Fi)was the smallest.[Conclusion]According to the improved Nemerow comprehensive fertility evaluation results,the soil comprehensive fertility of jujube plantation in the southeastern margin of Tarim Basin is at a medium level.It is determined that total nitrogen is the main factor limiting soil comprehensive fertility.Based on this result,appropriate fertilizers are selected and appropriate soil nutrient management is adopted to increase soil nutrient content,improve soil water and fertilizer retention capacity,and improve soil pH,thereby improving soil fertility and improving soil quality.