水生动植物联合作用净化不同富营养化景观水体研究

Evaluation of Aquatic Animals and Plants on Different Levels of Eutrophic Landscape Waters

选择睡莲(Nymphaeatetragona)、轮叶黑藻(Hydrillaverticillata)、鲢鱼(Aristichthysnobilis)和中华圆田螺(Cipangopludinachinensis)为实验对象,设置富营养和极富营养两种浓度梯度,通过室外试验探讨不同动植物及其组合对两种浓度水平中总氮(TN)、总磷(TP)及叶绿素a(Chl-a)的净化效果。结果表明,在富营养和极富营养水平中,均以睡莲和黑藻组合对TN和TP的去除效果最好,TN去除率分别为66.4%和42.3%,TP去除率分别为97.1%和89.6%,TP去除率分别高出相应对照组53.2和35.3个百分点;鲢鱼和中华圆田螺的加入会引起TN和TP的升高,但是由鲢鱼、中华圆田螺、睡莲和黑藻组成的组合对藻类的抑制效果最好,其Chl-a含量始终保持最低含量,日均值不超过1.16 mg/m3。因此,鲢鱼、中华圆田螺、睡莲和黑藻联合作用对富营养化水体具有明显的净化效果,其协同作用可为景观湖泊富营养化控制提供理论基础和科学依据。

Nymphaeatetragona, Hydrillaverticillata, Aristichthysnobilis and Cipangopludinachinensiswere selected as the experimental objects, and eutrophic and heavy eutrophic levels of water were set. The researches on purifying of the total nitrogen （TN）, total phosphorus（TP）and chlorophyll a（ Chl -a） by different aquatic animals and plants in the two eutrophic water bodies were carried out at outdoor conditions. Results showed that the removal of TN and TP with combination of Nymphaeatetragonaand Hydrillaverticillatawere best in both eutrophic and heavy eutrophic waters. TN removal rates were 66. 4% and 42. 3%, respectively, and TP removal rates were 97. 1% and 89. 6%, respectively, and TP removal rates were higher than the corresponding control groups with 53.2 and 35.3 percentage points, silver carp and snails could lead to the increase of concentration of TN and TP, but the combination of silver carp and snails and aquatic plants could inhibit the growth of algae most effectively, in which the Chl - a concentrations were always kept to a minimum contents of no more than 1.16 mg - m - 3 daily mean. Therefore, the combined effects of silver carp and snails and Nymphaeatetragona, Hydrillaverticillataon the purification of eutrophic waters is significant, which would provide a theoretical basis for eutrophication control of landscape lake.