Study On The Improvement Effect And Mechanism Of New Conditioners On Coastal Saline Soil

Coastal beaches in Jiangsu are rich in resources and are one of the important reserve land resources for the development of agriculture and animal husbandry.At present,the methods for developing and utilizing tidal flats have become mature and diverse,but the soil developed through reclamation is still not suitable for crop growth,and it is necessary to explore a way to use saline soil more efficiently.In recent years,the mode of improving saline soil and increasing crop yield through the combined application of conditioners and fertilizers has become very widespread in coastal areas.This thesis uses a new type of soil conditioner"Yanpa",and takes Jiangsu coastal saline soil as the research object.After applying the conditioner,the crop growth status,soil physical and chemical properties,and soil microbial diversity are analyzed.The biological process and mechanism of"Fear"on the improvement of coastal saline soil.The main findings are as follows:（1）After applying the conditioner"Yanpa",compared with the control,the water content of wheat and rice did not change significantly,but the root length and plant height increased significantly,and the number of effective grains per plant and yield also increased.At the same time,the content of total nitrogen,total phosphorus and total potassium in the crops is also higher than that of the control,and the content is higher with the increase of the amount of application.（2）After applying the conditioner"Yanpa",the soil salt content and SAR in the rhizosphere and non-rhizosphere soils of the Tiaozini Reclamation Area and Shuntai Farm were significantly reduced.When the application amount of the conditioner increases,the effect of reducing the salt content in the soil is more significant.In addition,the content of Ca²⁺,Mg²⁺,Na⁺,K⁺in rhizosphere and non-rhizosphere soils was significantly reduced,and the ion content reduction effect was better as the amount of conditioning agent increased,but there was no significant difference.The application of the conditioner"salt fear"has no obvious regularity in the influence of soil p H value.（3）After applying the conditioner"Yanpa",in the rhizosphere and non-rhizosphere soils,the organic matter content increased significantly,the content of available phosphorus and available potassium increased,and the content of alkali hydrolyzed nitrogen increased significantly.Increasing the lifting effect is more significant.（4）After applying the conditioner"salt fear",the water content and bulk density of the saline soil in the two regions decreased,the percentage of aggregates>5 mm in size decreased,and the percentage of aggregates in 0.25-5 mm size increased,the percentage content of the aggregate particle size of<0.25 mm is reduced.（5）After applying the conditioner"Yanpa",the catalase activity in both rhizosphere and non-rhizosphere soils increased,but there was no significant difference;except that the alkaline phosphatase activity decreased significantly in the non-rhizosphere 10-20 cm soil layer In addition,soil alkaline phosphatase,urease and invertase activities were significantly increased in rhizosphere and non-rhizosphere soils,but catalase activity and invertase activity decreased with the increase in the amount of application,and urease The activity and alkaline phosphatase activity are better with the increase of the dosage,but there is no significant difference.（6）Compared with a single conditioner,the compound conditioner added with"Yanpa"has a more significant impact on the microbial diversity in the soil.Among them,the number of bacterial species in the soil CK>J>YJ>YJS,CK>S>YS>YJS,and there are significant differences;the number of fungal species in the soil YJ>J>CK>YJS.The Chao1 index of the number of fungal species in the soil shows YS>CK>YJS>S,and the Shannon index shows S>CK>YJS>YS.（7）Compared with a single conditioner,the compound conditioner added with"salt fear"has a more significant impact on the quantity of a certain species in the soil.Among them,in addition to the addition of the compound conditioner YJ,the content of Proteobacteria in the soil increased compared with the single conditioner J,and the content of Proteobacteria in the soil was reduced compared with the single conditioner S after applying the compound conditioner YS.The content of Bacteroidetes,Firmicutes,and Ascomycota in the soil with the compound conditioner YJ and YS added with"Salt fear"was significantly increased compared with the single conditioner J and S,and the content of Chloroflexi,Actinobacteria,Unidentified and Basidiomycota was significantly reduced.In addition,compared with a single conditioner,the compound conditioner added with"Yanpa"has significant changes in soil microbial function,the saprophytic and symbiotic effects of fungi have been significantly improved,and the number of fungal pathogens has been significantly reduced.The results of the study show that adding the conditioner"Yanpa"to saline soil can not only improve crop quality and yield,but also reduce soil salinity,reduce soil bulk density,improve soil aggregates,increase the content of available nutrients in the soil,and strengthen the soil.Enzyme activity,increasing soil microbial diversity,etc.,improve the physical and chemical properties and structure of soil,and achieve the effect of improving coastal saline soil,providing a scientific basis for elucidating the mechanism of improving the function of coastal saline soil by conditioners.