摘要
通过土培实验,研究了黑麦草对以pp'-DDT,ν-BHC,HCB为代表的多氯代有机物(PCOPs)污染土壤的修复效果和根际土壤性质的动态变化。结果表明:种植黑麦草90d后,土壤中PCOPs下降了19.01%~41.75%;在黑麦草生长的前期和中期(0~60d),土壤中PCOPs下降较快,黑麦草对PCOPs吸收能力较强;黑麦草对高浓度污染土壤的修复能力较强;在去除土壤中PCOPs的作用上,黑麦草的吸收是轻微的,仅占1.20%~4.72%,土壤中PCOPs去除的主要原因是根际微生物的降解作用。种植黑麦草能改变根际环境,土壤pH值、有机质含量和过氧化氢酶活性的变化有利于促进土壤微生物对PCOPs的降解。
Polychlorinated Organic Pollutants (PCOPs) have characteristics of persistence, bioaccumulation, semi-volatility and high toxicity which threaten environment and human's health. In recent years, focus has been on phytoremediation to remove PCOPs in soil. This paper designed soil culture experiment to study the remediation effect of contaminated soil with PCOPs (pp'-DDT,v-BHC,HCB) by ryegrass and dynamic changes of soil property in rhizosphere. The results showed that after 90 days the content of PCOPs in soil decreased 19.01% ~ 41.75%. The decrease rate of PCOPs was quicker and the capability of absorbing PCOPs by ryegrass was higher at early and middle stages of ryegrass growth (0 - 60 d) than later stage(60 ~ 90 d). With the increase of PCOPs concentration, degradation rate of PCOPs and absorption capability of ryegrass increased. In other words, ryegrass has higher capability of remedying contaminated soil with PCOPs of high concentration than low concentration. For the removal of PCOPs in soil, the function of absorption by ryegrass was very little, and only account for 1.20% - 4.72%. The key reason for PCOPs removal from soil was microdegradation. Planting ryegrass can change rhizosphere environment, pH, content of organic matter and catalase activity changed accordingly with ryegrass growth, which has benefit the PCOPs removal from the soil.
出处
《环境科技》
2009年第1期4-8,共5页
Environmental Science and Technology
基金
"985"工程二期项目
中山大学重点资助项目(No.2005-90004-3172000)