湖南株洲土壤-水稻籽实间Cr迁移特征及其影响因素  

Migration of Cr Between Soil and Rice Grains and Its Influencing Factors in Zhuzhou,Hunan

作　　者：李思远 侯青叶[1] 汤奇峰[2] 余涛 杨忠芳[1] LI Siyuan;HOU Qingye;TANG Qifeng;YU Tao;YANG Zhongfang(School of Earth Sciences and Resources,China University of Geosciences(Beijing),Beijing 100083,China;National Research Center for Geoanalysis,Beijing 100029,China;School of Science,China University of Geosciences(Beijing),Beijing 100083,China)

机构地区：[1]中国地质大学(北京)地球科学与资源学院,北京100083 [2]国家地质实验测试中心,北京100029 [3]中国地质大学(北京)数理学院,北京100083

出　　处：《现代地质》2024年第3期775-783,共9页Geoscience

基　　金：国家自然科学基金项目(41773019)。

摘　　要：土壤-植物系统中Cr的生物地球化学行为以及高水平Cr对生态环境的影响一直备受关注。本文以湖南株洲作为研究区,采集了490件表层土壤样品、60套水稻籽实及根系土样品,对土壤与水稻籽实中Cr含量分布特征进行分析,对土壤Cr污染程度进行评价,探讨水稻籽实Cr生物富集系数(BCF)的影响因素,据此构建水稻籽实Cr的BCF预测模型,并对研究区水稻籽实Cr含量进行预测。研究区表层土壤Cr含量范围为48.50~240.60 mg/kg,中位值91.45 mg/kg。与全国和湖南省土壤背景值相比,研究区土壤Cr含量严重超标,主要受成土母质和人为活动影响。水稻籽实Cr含量范围为0.09~0.11 mg/kg,平均值0.10 mg/kg,均未超过限值。水稻籽实Cr生物富集系数主要与水稻根系土的Cu、TFe_(2)O_(3)、SiO_(2)/Al_(2)O_(3)显著相关,受根系土风化程度、铁氧化物和元素间拮抗作用影响。采用多元线性回归分析建立了研究区水稻籽实Cr的BCF预测模型,预测结果可靠。水稻籽实Cr含量预测结果显示研究区水稻籽实Cr含量均低于我国的稻谷Cr含量限值。The biogeochemical behaviors of Cr in soil-plant system and their impacts that high concentration of Cr in ecological environment have received a wide attention.This study takes Zhuzhou City in Hunan Province as the study area.Totally,490 surface soil samples and 60 pairs of rice grains and rhizosphere soil samples were collected.The concentrations of Cr in the soil and rice grains were analyzed and thereafter the pollution degree of Cr in the soil was evaluated.At the end,we ide.pngied the influencing factors of Cr bio-concentration factor(BCF)of rice grains and established the prediction model BCF of Cr in rice grains.The Cr concentrations of the surface soils range from 48.50 to 240.60 mg/kg,with an average value of 91.45 mg/kg.Comparing with the background values in soil of nationwide and Hunan Province,the concentration of Cr in the study area significantly exceeded the background,indicating mainly being affected by parent materials and anthropogenic activities.The Cr concentrations in rice grains vary from 0.09 to 0.11 mg/kg,with an average of 0.10 mg/kg.The Cr concentration doesn’t exceed the critical limit of Cr in food.The BCF of Cr in the rice grains is closely related to the concentration of Cu and TFe_(2)O_(3),and SiO_(2)/Al_(2)O_(3) in the rhizosphere soils,and was affected by the weathering degree,iron oxides and antagonism between elements in the rhizosphere soil.The prediction model for BCF of Cr in the rice grains is established by using multiple linear regression analysis and the prediction results are convincing.The predicted Cr concentration in the rice grains in the study area is below its critical limit.

关 键 词：株洲 水稻籽实 CR 影响因素 预测模型 

分 类 号：P595[天文地球—地球化学]