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(F_i) of soil pH, organic matter, CEC and total nitrogen did not reach the fertile level, among which the total nitrogen fertility coefficient(F_i) 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.