Study On Heavy Metal Enrichment Effect Of Sedum Macrophylla-Citrus Under Different Planting Patterns

The soil,one of the indispensable natural resources on which humankind depends,is also a necessary base for the production of raw materials for our lives.But in real life,the cropland that grows crop,heavy metal pollution is serious,this seriously delays China grain output and the rapid development of national economy,therefore,the author thinks it is necessary to carry on the research to repair the compound pollution of heavy metal in the cropland soil.In the article,the author conducted experiments on potted plants in the wild and used Cd,Pb,and As as the typical heavy metals for the study.For different varieties of citrus?Ehime 38,Daya No.1?,the use of joint restoration technology-``side production-edge strengthening repair"and the high-cumulative plant Sedum sedum,respectively,the absorption characteristics of heavy metals Cd,Pb,As,In addition,there are the remediation effects of concentrated plants in Pb,Cd,and As pollution,and the enhancement of different intercropping model measures in the safe production of low-pollution heavy metals in farmland crops and plant restoration.The results showed that intercropping could promote Ehime 38,Da Ya Tan No.1 and the increase of biomass,and promote the effect of whole stem and root or leaf.The leaf biomass of Ehime in the two intercropping models increased significantly in the open intercropping,and the well-formed roots and leaves increased significantly in the restricted intercropping.Intercropping has promoted the growth of the biomass,plant height,and leaf volume of the sedum,in which the treatment of open intercropping is greater than that of restricted intercropping,and the treatment of intercropping is greater than that of Ehime.Sedum's biomass,plant height and leaf volume increased rapidly within 90 years.The order of Cd,Pb,and As concentrations in each part of the citrus is from large to small:roots>stems>leaves>fruits,and intercropping does not change the order of heavy metal concentrations in each part of the citrus;Citrus TF _soil-root,TF _soil-subsoil,showed positive correlation,but in the process of upward transport of heavy metals,changes will occur with different accumulation sites.The order of the underground enrichment coefficient of citrus to heavy metals is Cd>Pb>As.Both are less than 0.6,indicating that citrus has very low concentration of heavy metals.The heavy metal absorption of Ehime is less than that of Daya,but there is no risk of heavy metal pollution in both citrus plants where such heavy metals are slightly contaminated.In addition to the underground part of YJA treatment and the upper part of YJD treatment,the inter-processing method has increased the content of heavy metals in the upper and lower parts of Jingtiandi.Intercropping increased the concentration coefficient of sedum on Cd,Pb,As,and the concentration coefficient of Cd was greater than 10,and sedum had greater restoration potential for Cd contaminated soil.Intercropping mainly produces effects on the root system of sedum,but has little effect on the transshipment effect of sedum itself.