Study On The Supply And Demand Balance Of Topsoil Stripping And Recycle In County Area

In the context of the shortage of resources for cultivated land,the increasing pressure to protect cultivated land and the increasing content of heavy metals in soil,in order to master the potential of topsoil stripping occupied by construction and the requirement for topsoil in land remediation,and to solve the dislocation problem of topsoil stripping and surface soil demand,this paper takes B city of Jiangsu Province as an example assessed the potential of surface soil stripping and the potential requirement of land remediation,and analyzed the balance level between regional topsoil supply and demand,so as to provide reference for the orderly development of soil stripping and reuse and for the preparation of special planning.Considering the soil fertility and environmental quality,earthwork site conditions and other factors,the evaluation index system of topsoil stripping and reuse potential was constructed in this paper from the aspects of quantity and quality.Methods of limit coefficient,weighted synthesis and spatial superposition were used in the paper.The results show that:Firstly,from 2014 to 2020,the soil quality of the agricultural land occupied by the plan is better,the first grade soil accounted for 57.33% of the total area of agricultural land occupied by the plan,and the soil fertility was not much different.The area of heavy metal content exceeded in topsoil is 7.31%,mainly distributed in F,Q,R,E and other towns.Surface stripping potential is dominated by I grade and II grade,the total quantity potential is 754.52 × 104m3;F town,K town,P town,Q town,and R town are the focus towns of topsoil stripping;A town,E town,G town,J town,L town,M town,N town,and S town are the secondary focus towns of topsoil stripping.Secondly,the soil quality was better in the region of topsoil recycling,and the first grade soil accounted for 69.84%.The soil fertility of the high standard farmland is similar to that of the occupied agricultural land by construction.The content of heavy metals in the third grades of soil was over standard.It is mainly distributed in B town,J town and Q town,and the situation of Heavy metals exceeded in industrial waste land is significant.The demand potential level of topsoil is main grade I,and the total quantity of potential demand is 1152.62 × 104m3;E town,B town and Q town are the main towns of topsoil reuse,followed by G town and J town.Thirdly,the supply of surface soil in the county is less than the demand.The balance of topsoil demand in the administrative village itself,among villages in the same township,and among different towns is 22.55%,23.52% and 53.93% of the total demand respectively.The transport distance of topsoil in most towns is about 10 km,the average transport distance of topsoil is farther in B town,E town,G town,Q town.Based on the above research,the following conclusions are drawn: The quality of the topsoil occupied by construction in the study area is higher,but the quality and quantity of the topsoil which is stripped from the agricultural land can not meet the demand of topsoil in land consolidation.According to the principle of topsoil deployment,the balance of topsoil supply and demand was carried out in turn in the administrative village itself,among villages in the same township,and among different towns.Master the source of topsoil and the average distance of transport,provide reference for the formulation of the soil stripping and reuse planning.