摘要
测定京石、京津塘和首都机场高速公路两侧植物枝叶和路边土壤Pb、Cd、Cu、Cr含量,研究4种重金属元素在高速公路两侧的扩散特征以及车流量大小与重金属含量间的相关关系。结果表明:Pb是车辆尾气重金属污染的主要污染源之一,高速公路两侧树木器官和不同土层Pb含量均随距路距离的增大而逐渐降低。Cu含量与距离高速公路的远近有一定关系,但变化情况因道路而异,且受车辆类型影响较大。而Cd、Cr含量和林带状况无明显关系。研究结果还进一步表明:高速公路沿线的重金属污染程度与车流量大小密切相关,对于日均车流6万辆的公路而言,高速公路两侧80m范围是重金属污染最集中的扩散区域;而40~60m的毛白杨林带(高度≥10m)对高速公路(日均车流量5万~8万辆)车辆尾气重金属污染有较好的吸收屏障效果。在此基础上,针对高速公路沿线防护林带配置策略和宽度问题进行深入探讨,基于林带防护功能和沿线农业生产食品安全角度,提出从路基向外,按照养护带、自然带和缓冲带3种土地利用类型配置防护林带,并分别提出建设模式和管理方式。
Heavy metals pollution of automobile particle matter is more and more serious with the development of vehicles industry and highway construction. And the forest belts along the road have been greatly emphasized on their functions of decreasing pollution. This article summarized the ecological influence of pollution of automobile particle matter, scope of heavy metal dispersion, screen effect of highway greenbelt and the use strategy of land along the highways. Three highways (Beijing- Shijiazhuang highway, Beijing-Tianjin-Tanggu highway, Airport highway) were used to study the characteristic of heavy metal dispersion and the relationship between traffic flows and heavy metal content. And the traffic flows of three highways are respectively 100 000, 59 000 and 80 000. The contents of Pb,Cd,Cu,Cr in soil and organs of trees( Populus tomentosa)along the highway were measured. The results showed that Pb was the main source of traffic tail gas pollution and its content decreased in different soil layers and tree organs with extends of the distance away from the highway. The content of Cu was also related with the distance away from the highway, but it was greatly influenced by the characteristic of the road and vehicles. There was little correlation between the contents and distributiong of Cd, Cr and forest belt width. The range of heavy metals dispersion was mainly within 80 m apart from the highway. And the heavy metal pollution made by tail gas of vehicles on the highway (50 000 〈 average traffic flow per day 〈 80 000) could be effectively decreased by 40 ~ 60 m poplar forest belt (height ≥ 10 m). In addition, the arrangement strategy and width of protective forest along the highways were also comprehensively studied in this paper. According to the pollution grades of road and spatial differentiation of land near the road, the different managing strategy with different disturbance degree were carried out for different reach of the road. And the utilization strategy should be classified and aimed at maintain zone, natural zone and buffer zone respectively with the distance away from the highway. Some scientific suggestions on highway design and construction, pattern of agricultural production along highway and highway environmental protection were also provided.
出处
《林业科学》
EI
CAS
CSCD
北大核心
2007年第3期1-7,共7页
Scientia Silvae Sinicae
基金
国家科技部十一五攻关重大专项课题(2006BAD03A19和2006BAD03A06)。
关键词
高速路
林带
车辆尾气
重金属污染
屏障作用
配置策略
highway
forest belt
tail gas of vehicles
heavy metals pollution
pollution controlling
arrangement strategy