水生动植物协同净化系统对鳜鱼养殖池塘水质与经济效益的影响

Effects of aquatic animals-plants synergistic purification system on water quality and economic benefit in mandarin fish pond

为研究水生动植物协同净化系统(褶纹冠蚌+水蕹菜+水稻)对鳜鱼养殖池塘水质与经济效益的影响,设计3个处理,分别为0-F组(对照组,无净化系统)、10%-F组(净化组,水蕹菜和水稻覆盖率各5%)和30%-F组(净化组,水蕹菜和水稻覆盖率各15%),净化组中各塘褶纹冠蚌密度均为每667 m 250只。试验期间定期监测水质和蚌生长情况,结束时测定鳜鱼成活率、产量与水生植物收获量。结果显示:各处理组水温、pH值无显著差异,但净化组的透明度始终高于对照组;试验结束时,0-F组的总氮(TN)质量浓度比初始增加35.5%,10%-F组和30%-F组的TN质量浓度分别比初始时降低23.8%和49.0%,NH^(4+)-N质量浓度分别增加167%、53%和34%,COD_(Mn)质量浓度分别增加138.5%、100.0%和88.9%,各组总磷(TP)质量浓度随时间呈现波动式下降趋势;水质、鳜鱼成活率、产量和经济效益均以30%-F组最优,10%-F组次之,0-F组最差。10%-F组水蕹菜和水稻单产均高于30%-F组,蚌湿重增长率30%-F组高于10%-F组。总体而言,动植物协同净化系统可明显提升鳜鱼养殖池塘水质与经济效益,且植物覆盖率为30%的净化系统应用效果优于覆盖率为10%的净化系统。

In order to clarify the effects of the synergistic purification system of aquatic animals-plants(Ipomoea aquatica+Oryza sativa+Cristaria plicata)on water quality and economic benefits of mandarin fish(Siniperca chuatsi)culture ponds,one control group(0-F,without purification system)and two purification groups with a plant coverage rate of 10%(10%-F,5%coverage for each of water spinach and rice)and 30%(30%-F,15%for each of water spinach and rice)were set up.Crested mussels were also hunging cultured(50 ind per 667m 2)in the ponds in the latter two groups.The water quality and growth rate of mussels were regularly monitored during the experiment,and the survival rate,yield and harvest of aquatic plants were determined at the end of the experiment.The results showed that there was no significant difference in water temperature and pH value among different groups.The water transparency of the purification groups was always higher than that of the control group.Compared with the initial mass concentration,the final mass concentration of total nitrogen(TN)in the 0-F group increased by 35.5%,and that of the 10%-F group and 30%-F group decreased by 23.8%and 49.0%,respectively.The final mass concentration of NH^(4+)-N in 0-F group,10%-F group and 30%-F group increased by 167%,53%and 34%of the initial mass concentration,respectively.The final mass concentration of COD_(Mn) in 0-F group,10%-F group and 30%-F group increased by 138.5%,100.0%and 88.9%compared with the initial mass concentration,respectively.The total phosphorus(TP)mass concentration in each group showed a fluctuating downward trend with time.At the end of the experiment,the water quality,mandarin fish survival rate,yield and economic benefit were the best in the 30%-F group,followed by the 10%-F group,and the 0-F group was the worst.The per unit area yields of water spinach and rice in the 10%-F group were higher than those in the 30%-F group.The wet weight growth rate of mussels in 30%-F group was higher than that of 10%-F group.In general,the synergistic purification system can significantly improve the water quality and economic benefits of mandarin fish ponds,and the application effect of the purification system with 30%plant coverage was slightly better than that of purification system with 10%plant coverage.