摘要
Abstract
Thirty six locations were selected as sampling spots within the municipal areas of Zhengzhou. Contents of heavy metals in the leaves of Buxus megistophylla, the most widely distributed urban shrub in the city and in the soils were determined. Average contents of nickel (Ni), lead (Pb), chromium (Cr) and zinc (Zn) in the leaves were 6.83, 8.38, 13.60 and 21.10 mg · kg-1 , respectively. Means of pollution index (ratio between the content in the sample from the research area to that from the control area) of these four metals were 1.86, 1.52, 2.15 and 2.03, respectively. Comparison of heavy metal contents in different urban functional areas indicated that highest contents of Ni and Cr in industrial area, Zn in street side,and Pb in residential community. Integrated pollution indices ranked industrial area＞residential area, bus station＞organization＞street side＞commercial area. No significant correlation was found between leaf heavy metal content and that of the soil, or heavy metal availability of soil in most cases, factor analysis showed that heavy metal contents in leaves and in soils were governed by different factors. The results suggest that the primary sources of heavy metal accumulation in the leaves are industrial activities, daily activities of residents and motor transportation, root uptake however, is not the main path way for heavy metal accumulation in the leaves.关键词
郑州/大叶黄杨/重金属/功能区Key words
Zhengzhou/ Buxus megistophylla/ heavy metal/ functional area分类
资源环境
