Effects Of Controlled-release Fertilizer With Soil Conditioner On Maize-wheat Growth And Soil Nutrients In Coastal Saline Area

The coastal saline-alkali land is bigger in China.The Bohai Sea is the main coastal saline-alkali soil distribution area in China.The salt content is high and the proportion of soil nutrient is uneven.Yield and quality,as the use of soil resources in agricultural production is limited.Ministry of Science and Technology,the Chinese Academy of Sciences in 2012 proposed "Bohai granary" project plan,through the use of scientific and technological means,combined with local resources,to build a moderate scale of modern agricultural production system.There are many ways to improve the use of saline-alkali soil,reasonable scientific application of fertilizer and soil conditioner is one of the measures.The controlled release fertilizer has the advantages of slow nutrient release,slow salt release due to nutrient release,high nutrient utilization rate,and no need of topdressing once.Humic acid soil conditioner has the functions of reducing soil pH and regulating soil physical properties.The effects of application of controlled-release fertilizers and soil conditioner on saline-alkali soil growth and saline-alkali soil chemical properties were studied.In this experiment,field experiment of saline-alkali soil near Bohai Sea was conducted to compare with the conventional fertilization of farmers.Based on the situation of local soil nutrient content,the effects of combined application of humic acid regulator and bio-organic fertilizer on mild NP The soil pH,salinity,soil nutrient,organic matter,crop yield,nutrient use efficiency and economic benefit were studied.The data of soil fertility improvement in coastal saline soil were provided.The main results are as follows:(1)Complex controlled release fertilizer(CRF),humic acid complex release fertilizer(HCF),complex controlled release fertilizer combined with humic acid conditioner(ACRF),complex controlled release fertilizer combined with microbial organic fertilizer(OCRF)have varying degrees of reduced Coastal Saline Soil pH in the maize field experiment.(2)Different treatments on the total salt salinity had some effects to some extent,but not significant.(3)Compared with CCF treatment,the CRF of NO3-and NH4+ in thbig bell stage,mature stage and ripening stage of maize were higher than those of CCF treatment,and the increase rates were 8.5%~23.6%,and 0.95%~13.0% respectively.The N and P content in maize plants and grains of the CRF were increased.(4)The 1000-grain weight of ACRF was the highest,353.2g,and the lowest 1000-grain weight of OCRF was 326.6g,which were significantly different from CCF treatment.The yields of CRF and HCF were 8832 kg·hm-2 and 8125 kg·hm-2,respectively,which were 15.23% and 6.01% higher than that of the conventional fertilization treatment,and the differences were significant,per hectare net income also increased 2578 yuan,223 yuan.(5)In the wheat field experiment there was no significant difference in total salt content between CRF and CCF in 0-20 cm soil,and it reduced obviously in 20-40 cm soil,the decline was 6.6%~13.2%.(6)In the wheat field experiment,compared with CCF treatment,CRF increased the content of soil nitrate,ammonium nitrogen and available phosphorus in most of wheat growth stages in different growth stages,and increased by 3.3%~17.0%,1.1%~24.3% and 15.2%~33.8%.In the 20-40 cm soil,the increase rates were 5.5%~14.6%,9%~14.1%,23.2%~28.7% ?(7)In the wheat field experiment,humic acid slow-release fertilizer,coated slowrelease special fertilizer with bio-organic fertilizer and with the application of humic acid conditioning agent treatment compared to other treatments increased soil organic matter content,reached a significant level.(8)The average grain weight of coated slow-release and special-release fertilizers was the highest,which was 37.45 g,which was significantly higher than that of farmers.The yield of wheat was 5963kg·hm-2,which was 15.4% higher than that of farmers with significant difference.(9)The humic soil conditioner and the microbial organic fertilizer did not achieve the expected result in the experiment,its appropriate application and the mode of application should be further studied.Under the condition of the application of complex controlled release fertilizer and soil conditioner in the experiment,considering the yield and economic benefit,the CRF may be the best fit treatment in low saline-alkali saline-alkali soil to be suggested to farmers to plant maize and wheat.