污染梯度效应下大熊猫栖息地重金属暴露风险

The Potential Risks and Exposure of Giant Panda Habitats to Heavy Metals under the Effect of Urban Environmental Pollution Transport

秦岭是珍稀物种大熊猫、羚牛等的栖息地,易受到西安和汉中城市污染扩散影响。文章对秦岭山区土壤和竹子重金属的2年研究结果显示:(1)城区土壤Cu的平均浓度(44.36 mg/kg)显著高于山区,山区Cd的平均浓度(0.37 mg/kg)显著高于城区(0.26 mg/kg);(2)竹子中重金属Hg、Cr的平均浓度分别超过了食品限量标准的10、33倍;(3)大熊猫栖息地重金属暴露途径的致癌风险顺序为:摄入竹子>摄入土壤>吸入土壤颗粒物;(4)大熊猫通过摄入竹子的重金属暴露风险超过了10^(-4),表明存在致癌风险的可能性较高。鉴于秦岭是中国重要的生态系统和珍稀物种栖息地,建议今后加强管控区域大气污染物的排放,以保护区域生态环境。

The Qinling Mountains are the habitats of rare species such as giant panda and takin,and are vulnerable to urban pollution transport of Xi’an and Hanzhong City.The two-year study on heavy metals in soil and bamboo in the Qinling Mountains showed that:average concentration of Cu(44.36 mg/kg)in urban area was significantly higher than that in mountainous area,and the average concentration of Cd(0.37 mg/kg)in mountainous area was significantly higher than that in urban area(0.26 mg/kg).The average concentrations of Hg and Cr in bamboo were 10 and 33 times higher than the national food limit standard respectively.The carcinogenic risk of heavy metal exposure in panda habitats was in the order of bamboo ingestion>soil ingestion>inhalation of soil particles.The risk of heavy metal exposure of giant pandas through bamboo ingestion exceeded the 10^(-4) level,which suggests a probability of high cancer risk.Considering that the Qinling Mountains are an important ecosystem and habitat for rare species in China,it is suggested to strengthen the control of regional air pollutant emissions in the future to protect the regional ecological environment.