生物浮床在泥鳅养殖中对水体生境的影响

Influence of Floating Plant Bed on Habitat of Cultured Loach(Paramisgurnus dabryanus)

为探讨生态浮床对养殖池塘水质净化效果以及对浮游植物群落结构的影响,试验设置对照组1个、处理组3个,浮床覆盖率分别为5%、10%、15%,每组3重复,定期测定水化学指标和藻类的群落结构。试验结果表明:与对照组相比,处理组能够提高水体透明度,降低水体中的总氮(TN)、总磷(TP)、化学耗氧量(COD)、氨氮(NH_(4+)-N)、亚硝酸盐(NO_2-N)等水化学指标,并且随着浮床覆盖率的增大,净化效果越明显。在养殖中期,处理组浮游植物的种数明显高于对照组,但其生物量却低于对照组。处理组大鳞副泥鳅的成活率、增重量显著高于对照组,但是随着浮床覆盖率增大,大鳞副泥鳅增重量并没有随之增加。因此生物浮床对改善池塘水质、丰富藻类组成、降低过高浮游植物生物量以及提高大鳞副泥鳅的成活率有一定的作用。本试验中,浮床覆盖率15%时对大鳞副泥鳅养殖有一定的应用价值。

In order to determine the effects of biological floating bed on the water quality and the phytoplankton community of loach culturing ponds, we conducted continuous and regular surveys on the phytoplankton community and the water quality index. The test groups included one control group and three treatment groups with a floating bed coverage rate of 5%, 10% and 15%, respectively, three repeats each group. The results showed that the floating bed improved the transparency of the water and reduced the total nitrogen, total phosphorus, COD, ammonia nitrogen, nitrite and other chemical indicators compared with the control. With the increase of floating bed coverage rate, the purification effect became more and more obvious. In the middle of culturing period, phytoplankton species in treatment groups were significantly more than those in the control, but the quantity of phytoplankton in treatment groups was lower than that in the control. The loach （Paramisgurnus dabryanus） survival rate and the weight gain of the treatment groups were significantly higher than those of the control, but loach weight did not increase with the increase of floating bed coverage rate. Therefore biological floating bed may aid to improving the water quality, enriching algae species, reducing the risk of high biomass and improving loach survival rates. In this test, floating bed coverage rate at 15% was certainly applicable in loach culturing ponds.