A 20-YEAR LONG TERM STUDY OF YIELD SUSTAINABILITY AND SOIL FERTILITY AFFECTED BY FERTILIZATION AND APSIM CLIMATIC CHANGE MODEL OF URUMQI, XINJIANG, CHINA .

To achieve high crop production, long-term field experiments 20 years (1990-2010) were conducted at Urumqi-China. In this study, we investigate the effect of organic and inorganic fertilization treatments on maize, spring wheat, and winter wheat cropping system in Urumqi, Xinjiang China. We investigated the impact of soil fertility, crop yield sustainability index, nutrients balance, carbon sequestration (CSR), and climatic change model through the Agricultural Production Systems Simulator (APSIM). Five treatments were studied: CK (control); NPK (inorganic fertilizers nitrogen, phosphorus, and potassium); NPKM and manure; NPKS & straw and NPKM2 and manure (the rate of manure was double from NPKM. The study showed that the combined application of inorganic and manure application (NPKM2 and NPKM) significantly increased the crop grain yield and soil fertility and sustainable yield index were higher as compared to NPK and CK. The changes of maximum and minimum temperature (+2), decreasing precipitation (-10), and increased CO₂ level (350-650 ppm) from observed values, simulated in the climatic model will significantly decrease essential soil water (191.2- 181.1 mm), runoff (0.43-0.40 mm), total NO₃^- (1444.0 to 1422.5) kg ha^-1, and leaching (0.75-0.73) and runoff (0.43 mm to 0.40 mm) while increased total NH₄⁺ (35.1 to 41.72) kg ha^-1 . [ABSTRACT FROM AUTHOR]