一种生物净水剂对河蟹养殖水体水质净化效果研究

The biological cleaning agent Pondplus was dowsed each ten days at different dosage into breeding ponds for Chinese mitten crab with stocking rate at 12 000 ind./ha, to evaluate its purification effects on water environment in breeding ponds and its effects on Chinese mitten crab growth. The results showed that dousing treatment improved the water quality significantly as evaluated according to the parameters of DO, CODMn, NH4 ＋ - N and NO2 - -N. Particularly, when the air temperature was higher than 35℃, the diurnal observation on DO values at the bottom of ponds showed that dousing at 450 g/（ ha•m） gave a DO value higher than 4 mg/L all day long, which was 2 mg/L higher than that of control. The observed increase of Chinese mitten crab were 14. 9% , 27.8% , 27.8% by average weight, when dousing at 150, 300, 450 g/（ha • m） , respectively. Accordingly, the production increased by 8.5%, 11.9%, 18.6% through its promotion of Chinese mitten crab growth, and the economic efficiency were enhanced by 96.2% , 159.8% , 180.9%.

The Purification Functions of a Biological Cleaning Agent on Aquaculture Water of Chinese Mitten Carp