Field experiment was conducted to investigate the effects of combined application of organic and inorganic fertilizers on soil physical and chemical properties and crop yields in newly reclaimed alkali-saline land at Yellow River irrigation district of Northwest China's Gansu province. The results showed that combined application of organic and inorganic fertilizers significantly improved soil physical properties. Soil average bulk density in 0~10 cm, 10~20 cm, and 20~40 cm layers was respectively reduced by 9.31%, 6.16%, and 4.29%, whereas the total porosity of that increased by 10.00%, 7.56%, and 10.00%, respectively. Combined application of organic and inorganic fertilizers reduced the soil compaction in 0~20 cm layer, and the reduction range increased with the increase of organic manure. Application of fertilizers improved nutrient status of soil in newly reclaimed alkali-saline land. Compared with N0M0 treatment, organic matter was increased by 5.2%~24.0%,total nitrogen, phosphorus and potassium by 20.83%~58.33%, 10.85%~81.40%, and 2.80%~15.42%, and available nitrogen, available phosphorus and available potassium by 4.18%~113.42%, 51.43% ~312.38%, and 5.84%~32.22%, respectively. Application of fertilizers significantly improved crop yields by 13.4%~168.8%. Nitrogen fertilizer played a leading role in increasing crop yield by a range of 53.5%~130.7%, and the organic manure by 8.8%~22.1%%. Meanwhile, combined application of organic and inorganic fertilizers significantly improved the performance of maize plant, with plant height, ear length, grains per row of maize in N 300 kg·hm-2 and organic manure 24 t·hm-2 being the highest, and similarly the ear diameter, rows per ear, hundred grain weight in N 600 kg·hm-2 and organic manure 24 t·hm-2. |