The Remediation And Utilization Of Copper Contaminated Soils Using Different Planting Patterns Combined By Oenothera Glazioviana Mich.and Elsholtzia Haichowensis S.

The problem of soil heavy metal pollution in our country has attracted more and more attention.Phytoremediation is one of the important remediation methods for heavy metal contaminated soil.The pot experiment and field experiment were conducted in the research,the copper enrichment plant Elsholtzia haichowensis and low transfer copper crop Oenothera glazioviana as test materials.The total amount of copper enriched by plants,the content of copper in soil,the change of soil nutrient content,the change of microbial community in soil and the remediation efficiency of copper contaminated soil were compared and analyzed by a variety of planting patterns in monoculture,continuous cropping,intercropping and rotation.In order to provide the basis for the side repair and utilization of heavy metal contaminated soil.Through field density test,sand mixed matrix pot experiment and pot experiment of N,P and K fertilizer to study the suitable cultivation and fertilization methods of Oenothera glazioviana.The results show that,the growth diameter of Oenothera glazioviana is 0.5?1.2 m per plant,the plant height is 1?1.3 m per plant.Plant growth and yield were taken into account comprehensively,planting density can be selected about 2700?3300 per mu.Oenothera glazioviana is endurable with barren and it can grow normally in 4 level soil with medium and low nutrient levels.Oenothera glazioviana grows in the environment which N,P and K were 372.7 mg kg-1,153.7 mg kg-1 and 167.7 mg kg-1 respectively,the biomass of plant reached the highest level.Through three years of pot experiment,comparison the remediation of copper contaminated soil by Oenothera glazioviana and Elsholtzia haichowensis in monoculture,intercropping,continuous cropping,crop rotation and so on.The results showed that,(1)In the rotation cropping model,the dry weight accumulation and total copper accumulation were the highest.The copper content and the available copper in the soil crop rotation mode compared with the initial idle decreased.Oenothera glazioviana and Elsholtzia haichowensis rotation cropping patterns can be used for remediation of copper contaminated soil.(2)The main constituents of the exudates of Oenothera glazioviana in autumn are acids and aldehydes,and the percentage of organic acids in root exudates increased after copper treatment.The main component of Elsholtzia haichowensis root exudates are acids and esters.(3)Intercropping and rotation cropping patterns can improve soil fertility and increase the number and type of beneficial microorganisms in the soil.(4)Continuous cropping of Oenothera glazioviana for a long time will lead to soil acidification,resulting in continuous cropping obstacles.With Elsholtzia haichowensis intercropping,rotation planting can enhance soil bacterial community richness and diversity.Effectively avoid the phenomenon of continuous cropping obstacle.The economic yield and the remediation effect of contaminated soil were compared of Oenothera glazioviana and Elsholtzia haichowenis in continuous cropping and rotation planting pattern by field test.The results showed that cultivation rotation can get best economic benefits,income is 1510 yuan mu-1 per year.Higher than the economic benefits of continuous cropping by Oenothera glazioviana or Esholtzia haichowensis.In copper polluted area by Oenothera glazioviana and Elsholtzia haichowensis rotation mode,to achieve the soil heavy metal pollution repair and utilization at the same time.