Tracing the behaviour of hexachlorobenzene in a paddy soil-rice system over a growth season  

作　　者：YANG Hua ZHENG Minghui ZHU Yongguan 

机构地区：[1]Research Center for Eco-Environrnental Sciences, Chinese Academy of Sciences, Beijing 100085, China.

出　　处：《Journal of Environmental Sciences》2008年第1期56-61,共6页环境科学学报（英文版）

摘　　要：Hexachlorobenzene （HCB）, a persistent organic pollutant （POP）, has been found in paddy soils. To improve the understanding of HCB contamination in paddy soils, a laboratory simulative study was carried out to investigate the behavior of HCB in a paddy soil and rice plants. This study was divided into three experiments. First, an experiment aimed to examine the evaporation of HCB in paddy soil. In the second experiment, rice was planted in 10 mg/kg HCB contaminated soil and after pot culture at 3, 6, 9, and 27 weeks （at maturity）, both soil and plant samplings were scheduled to be sampled. The soil samples comprised rhizosphere soil, nortrhizosphere soil, and unplanted contaminated soil, whereas plant samples included shoots, roots, and rice grains （dehusked）. Lastly, in this part, HCB in xylem saps was designed to be examined. The results showed that （1） the HCB translocation from paddy soil to rice by vaporization; （2） the HCB concentration in rice grains was surprisingly high; （3） the observed HCB decrease in rice rhizosphere offers a potential means for in situ HCB degradation; （4） HCB might not be transported along transpiration in rice.Hexachlorobenzene （HCB）, a persistent organic pollutant （POP）, has been found in paddy soils. To improve the understanding of HCB contamination in paddy soils, a laboratory simulative study was carried out to investigate the behavior of HCB in a paddy soil and rice plants. This study was divided into three experiments. First, an experiment aimed to examine the evaporation of HCB in paddy soil. In the second experiment, rice was planted in 10 mg/kg HCB contaminated soil and after pot culture at 3, 6, 9, and 27 weeks （at maturity）, both soil and plant samplings were scheduled to be sampled. The soil samples comprised rhizosphere soil, nortrhizosphere soil, and unplanted contaminated soil, whereas plant samples included shoots, roots, and rice grains （dehusked）. Lastly, in this part, HCB in xylem saps was designed to be examined. The results showed that （1） the HCB translocation from paddy soil to rice by vaporization; （2） the HCB concentration in rice grains was surprisingly high; （3） the observed HCB decrease in rice rhizosphere offers a potential means for in situ HCB degradation; （4） HCB might not be transported along transpiration in rice.

关 键 词：HCB paddy soil rice RHIZOSPHERE xylem sap 

分 类 号：X53[环境科学与工程—环境工程]