洛阳市城区雪松松针铅含量空间分布

Spatial Distribution of Pb Concentration in Cedar(Cedrus deodara) Needles in the Center of Luoyang City

通过对洛阳市城区居民区、商业区、工业区、风景区4种功能类型区中的11个采样点中的10～15年生雪松松针(SA)、地面落针(SB)和20～30年生雪松松针(SC)、地面落针(SD)中重金属Pb含量的测定,分析了洛阳市城区大气中Pb污染现状。结果表明:洛阳市城区雪松松针Pb含量平均为1.606mg/kg,属重金属轻度污染;居民区、商业区、工业区、风景区雪松松针Pb含量差异显著,表现为工业区>居民区>商业区>风景区;松针中Pb含量主要受冶炼、工业废气、汽车尾气排放等人为活动因素影响。雪松松针Pb含量分异性可以客观反映城市不同区域内大气Pb污染程度,这为城市环境保护研究提供了新方法,值得推广使用。

The concentrations of Pb accumulated by air pollution in the cedar（Cedrus deodara） tree needles from the center Luoyang City were measured.The needle samples were collected from 4 types of trees（SA： needles from 10~15-year-old trees,SB： fallen needles on the ground from 10~15-year-old trees,SC： needles from 20~30-years-old,and SD： fallen needles on the ground from 20~30-years-old） from 11 different locations with different degrees of metal pollution（residential,industrial,commercial and scenic regions）.Concentrations of Pb were determined for types and sampling regions.Results showed that average value of Pb concentrations in the cedar tree needles was 1.606 mg/kg,and the city was slightly polluted by Pb.There were significant differences in the Pb among residential region,commercial region,industrial region and scenic region,and decreased in the order of industrial region commercial region and residential region scenic region.The spatial variability of test heavy metals in cedar needles was mainly affected by the industrial discharge of the metals.The concentration of Pb in cedar tree needles can objectively and better indicate the air environmental pollution of heavy metals.It has been proved that this method is a good way in environmental protection by means of using the concentrations of heavy metals in cedar tree needles.