大气-土壤-小麦生态系统中铅的分布和迁移规律研究

研究铅在国道附近大气－土壤－小麦生态系统中的分布及其迁移规律。结果表明，大气中铅浓度与汽车流量成正比，而与风速、温度等相关性不明显；距公路越远，土壤及小麦中铅的含量越高，含是与距离呈一定的匀相关性，５ｍ及６０ｍ为其转折点；铅在土壤中由上上及在小麦体中由根向茎、穗的迁移较小；小麦各器官中铅含量大小依次为根〉叶〉穗〉茎〉籽。叶片、穗尚从大气中直接部分铅。在小麦不同生长阶段中，各器官积累铅量不同，其积累

DISTRIBUTION AND MOVEMENT OF LEAD IN THE AIR SOIL WHEAT ECOSYSTEM

In this paper, the distribution and movement of lead in the air soil wheat ecosystem around the 107 # state road were studied. The lead density (LD) in the air varied with a positive propotion to traffic volume, but there was no obvious correlation with wind speed and air temperature. The LD in soil or wheat organs, which showed a negative propotion to the distance from the state road, had two suddenly dropping points at 5m and 60m, but only a very little movement in soil from upper to lower layer, or in the wheat from root to stem, seed, ect.. The LD order in wheat organs was root>leaf>ear>stem>seed. The leaf or ear could also absorb lead from the air. Wheat organs had different lead accumulation in their different growing stage. As wheat grows, its organs could accumulate more lead.