【作者】 王媛；

【导师】 吕家珑；

【作者基本信息】 西北农林科技大学 ， 环境工程（专业学位）， 2016， 硕士

【摘要】 土壤作为人类赖以生存发展和城市建设基础所必需的生产资料之一,是最重要的自然资源和物质保障。工农业飞速发展导致重金属在土壤—植物—环境系统中受到的污染越来越严重。目前国内外关于土壤重金属污染的修复措施主要有物理措施、化学措施、生物措施、农业生态修复等措施。其中,植物修复措施作为一种绿色生态修复技术—土壤重金属通过超累积植物对其进行富集、吸收和转化作用。相比其他修复措施,具有安全、简便、环保、经济等优势。但在实际的土壤修复中,利用植物联合化学修复技术能更有效的解决土壤重金属污染问题,虽然这方面的研究已经取得了很大进展,但仍有很多难题需要探索解决。本试验采用盆栽试验,选取四种植物—向日葵、油菜、黑麦草、小白菜分别联合四种改良剂—钙镁磷肥、石灰、竹炭和膨润土对大茅坪铜矿矿区污染土壤进行修复研究,主要研究结果如下:(1)试验所用的修复植物向日葵、油菜、黑麦草和小白菜都对土壤铜、镉、锌、镉的污染具有一定耐性,相比单独种植植物,其改良剂联合植物修复均不同程度的对植株的生长表现出促进作用。特别是施加膨润土和石灰对提高植物的生物量有着极其显著的效果。(2)相比单独种植植物,施加改良剂降低了向日葵、油菜、黑麦草和小白菜植株地上部和根部铜、镉、锌、铅的含量。油菜和小白菜植株体内镉的浓度是地上部>根部以外,向日葵和黑麦草植株体内铜、镉、锌、铅的浓度以及油菜和小白菜体内铜、锌、铅的浓度均表现为根部>地上部分。可见,油菜和小白菜对镉的富集能力较强。此外,对比四种植物植株体内不同重金属的富集量来看,黑麦草对铜的吸收能力较强,油菜对镉、锌、铅的吸附能力较强。(3)相比单独种植植物,钙镁磷肥、石灰、膨润土和竹炭联合植物修复都对土壤有一定的固化效果,且总体固化效果表现为石灰>膨润土>钙镁磷肥>竹炭,均不同程度的降低了土壤中有效态重金属铜、镉、锌、铅的含量。综合来看,施加石灰和膨润土更能有效的降低土壤中交换态铜、镉、锌、铅的含量。结果表明,施加改良剂联合植物修复该矿区污染土壤有一定修复效果,植物—化学修复方式在该矿区的生态修复实践中具有较大的应用潜力。更多还原

【Abstract】 As one of the necessary means of production for human survival and development and urban construction, soil is the most important natural resources and material guarantee.However, with the rapid development of industry and agriculture, the pollution of heavy metals in the soil plant environment system has become more and more serious. At present domestic and foreign soil heavy metal pollution remediation measures mainly include physical measures, chemical measures, biological measures, agricultural ecological restoration measures. Among them, phytoremediation measures as a kind of green and ecological restoration technology, use some super accumulation plant absorption, enrichment and transformation of heavy metals in the soil.Compared to other repair measures, is safe,simple, environmental, economic and other advantages. But in the actual soil remediation, the use of plants and chemical remediation technology can be more effective to solve the problem of heavy metal pollution in soil, although this research has made great progress, but there are still many problems to be solved.This experiment using pot experiment, selected four kinds of plants, sunflower, rapeseed,ryegrass and Chinese cabbage respectively combined with four amendments, fused calcium magnesium phosphate and lime, charcoal and bentonite of DAMAOPING copper contaminated soil in mining areas for research and restoration, the main research results are as follows:(1) Test used in the repair sunflower plants, rape and Ryegrass and Chinese cabbage are on soil copper, cadmium, zinc and cadmium pollution has certain tolerance, compared to individual plant, and its modified agent combined with phytoremediation are different degree on plant growth performance a role in promoting. Especially the application of bentonite and lime has a very significant effect on increasing the biomass of plants.(2) Compared with individual plant, the content of copper, cadmium, zinc and lead in the shoot and root of sunflower, rape, rye grass and cabbage were decreased by applying the improved agent.The concentration of Cd in rape and Chinese cabbage plants is shoot > root,the concentrations of copper, cadmium, zinc and lead in sunflower and ryegrass plant is root>shoot, the concentrations of Cu, Zn and Pb in rape and cabbage were all shown to be theroot of the above ground parts. Obviously, rape and Chinese cabbage can enrich the cadmium.In addition, compared with the four kinds of plants in the body of different heavy metal enrichment, ryegrass on the absorption of copper is strong, rape on cadmium, zinc, lead adsorption capacity.(3) It is higher than that of single plant, fused calcium magnesium phosphate and lime,bentonite and charcoal plant combined repair are on soil have certain curing effect, and the overall effect of curing performance for lime > bentonite bentonite > calcium magnesium phosphate > bamboo charcoal are different degrees of reduced soil effective state of heavy metals copper, cadmium, zinc and lead content. On the whole, it is more effective to reduce the content of exchangeable Cu, CD, Zn and Pb in soil by applying lime and bentonite.The results showed that the application of the improved agent combined with plants to repair the contaminated soil in the mining area has a certain effect, and the plant chemical restoration method has great potential for application in the ecological restoration practice of the mining area.更多还原