紫茎泽兰和鬼针草对重金属铬的竞争富集作用

采用火焰原子吸收法考察了紫茎泽兰和鬼针草在重金属铬的胁迫下竞争富集作用。研究结果显示：紫茎泽兰对铬具有更强的耐受性，可以在50rag／kg铬的培养液里很好地生长。鬼针草对铬的耐受性较差，在20mg／kg铬的培养液里生长抑制。在相同的环境里鬼针草的富集系数大于紫茎泽兰，两种植物的EF在一定浓度范围内和培养液里铬含量正相关，超出其耐受极限浓度时，因为生长受到抑制而使EF降低。

Competitive Enrichment of Chromium for Eupatorium adenophorum and Bidens pilosa

In the paper, we study the competitive enrichment characteristics of Eupatorium adenophorum and Bi- dens pilosa under Cr stress by FAAS. The results showed that Eupatorium adenophorum had stronger tolerance than Bidens pilosa. Their, and it grew well in the culture solution with chromium at 50mg/kg. In the solution of 20mg/kg, the growth of Bidens pilosa was inhibited. In the same environment, Bidens pilosa had higer EF than Eupatorium adenophorum. The EF of the two plants had a positive correlation with the the concenttation of Cr with- in a certain range of the concentration. When beyond their extreme tolerance concentration, the growth was re- strained and the EF dropped.