Hg2+胁迫下细叶蜈蚣草对水体总磷去除效果的研究

采用室内培养分析测试方法,研究了在不同梯度浓度的Hg2 处理下,细叶蜈蚣草对水体总磷去除效果的动态变化情况。结果表明:对照组和Hg2 浓度为0.10 mg.L-1试验组在Hg2 处理的96 h内,细叶蜈蚣草对水体总磷去除率随着处理时间的延长而增加;0.50 mg.L-1和1.00 mg.L-1试验组在48 h内,细叶蜈蚣草对水体中总磷去除率一直上升,但96 h后对水体中总磷的去除率明显下降;Hg2 浓度大于1.50 mg.L-1的试验组中细叶蜈蚣草对水体中总磷去除率一直下降。同时,细叶蜈蚣草对水体总磷去除率的均值与Hg2 浓度亦均呈曲线关系,细叶蜈蚣草对水体总磷去除速率的均值与Hg2 浓度均呈曲线关系。

Effects of Hg2 + on Removal Rate of TP in Water by Egeria najas

The removal rates of TP in Water by Egeria najas under the stress of different concentrations of Hg~(2 )were studied.The removal rates of TP by Egeria najas increased in the controlled group and the group with 0.10 mg.L~(-1) Hg~(2 ) after exposure of 96h;they also increased in the groups of 0.50 mg.L~(-1) and 1.00 mg.L~(-1) Hg~(2 ) in 48 h,but declined after 48 h;when the concentration of Hg~(2 ) was above 1.00 mg.L~(-1),the removal rates of TP declined all the time.The regression relationship between the average removal rate of TP by Egeria najas(y)and the concentrations of Hg~(2 )(x) were:y_(24)= 3.3204x~(2)-28.244x 18.559,r~(2) being 0.9921;y_(48)= 6.8501x~(2)-44.775x 27.865,r~(2) being 0.9518;y_(96)= 13.398x~(2)-73.379x (30.406),r~(2)being 0.9823.The relationship between the average removal velocities of TP by Egeria najas(y)and the concentrations of Hg~(2 )(x) were:y_(24)= 0.0207x~(2)-0.1706x 0.1295,r~(2)being 0.9946;y_(48)= 0.0203x~(2)-0.1323x 0.0933,r~(2) being(0.9749);y_(96)= 0.0195x~(2)-0.1072x 0.0518,r~(2) being 0.9591.