Effect Of Combination Application Of Organic And Inorganic Fertilizers On Saline-alkali Farmland Improvement In Tumochuan Plain

Soil salinization will not only cause soil hardening and degradation and land desertification but also affect crop growth and reduce crop quality.The study of improving soil fertility and crop yield by applying organic fertilizers and chemical fertilizers to control saline-alkali land has become a hot research topic.Therefore,in order to study the improvement effect of different fertilization measures on the saline-alkali soil of the Tumochuan Plain,this experiment took the typical saline-alkali soil of the Tumochuan Plain as the research object.The effects of combined application of organic and inorganic fertilizers on soil moisture and salt transport and nutrient change characteristics and crop yield were studied by setting up eight treatments in field trial.Eight treatments were respectively no fertilization treatment（CK）and farmyard manure（M）and straw returning（S）and chemical fertilizer（F）and farmyard manure+straw returning（MS）and farmyard manure+chemical fertilizer（MF）and straw returning+chemical fertilizer（SF）and farmyard manure+straw returning+chemical fertilizer（MSF）.Eight treatments all contained the same amount of nitrogen.The results were as follows:（1）The soil water content was significantly increased by treatments of MSF and SF.Compared with the application of chemical fertilizer alone,other treatments could reduce soil p H and content of total salt and ESP（exchangeable sodium percentage）.The effects of inhibiting anti-salt and salt leaching in the soil layer of MSF and MS and S treatment was significant,and the desalination rates were 27.40%and 24.50%and 20.94%respectively.（2）The contents of ESP and CI^-and Ca²⁺and Mg²⁺were significantly decreased when applying Farmyard manure and straw returning and chemical fertilizer（MSF）.Farmyard manure+chemical fertilizer（MF）treatment significantly decreased SO₄^2-content by23.67%.Treatment of SF significantly reduced the contents of Na⁺and K⁺and CI^-.（3）Under different fertilization measures,soil organic matter at harvest period of treatment of M and MSF and S were increased by 0.19%-4.08%compared with that before sowing.The content of total nitrogen in the 0-10 cm soil layer were significantly increased by respectively under the treatment of MF and M and MSF.（4）Treatments of MS and MSF and MF all significantly increased the yield of sunflower,with an increase of 727 kg·hm^-2and 692 kg·hm^-2and 648 kg·hm^-2respectively.In summary,different treatments could improve soil salinization characteristics and water content and soil nutrient content and crop yield.The combined application of organic and inorganic fertilizers was better than the single application.Treatment of MSF and MS had the best effect on the improvement of soil physicochemical properties and soil salt inhibition and alkali reduction.So they were suitable for application in the Tumochuan Plain in Inner Mongolia.