稻虾养殖田放养黄鳝对水质及经济效益的影响

Effects of the Rice Field Eel(Monopterus Albus)Cultivation on Water Quality and Economic Benefit in the Rice-Shrimp Farming Model

为探究黄鳝的放养密度对稻虾养殖田环沟水质及综合经济效益的影响,设置了1个对照组(DX)和2个试验组(DXS1和DXS2)开展养殖试验,3组每667 m2黄鳝放养量分别为0,800,1600尾。结果显示,在稻田水质方面,试验组稻田水体中pH值、可溶性磷与对照组无显著性差异(P>0.05),氨氮、亚硝酸盐氮、总氮显著高于对照组(P<0.05)。在黄鳝和克氏原螯虾的生长方面,5—9月份,DXS1和DXS2黄鳝特定生长率分别为(0.583±0.249)和(0.479±0.202)%/d,其中6月份黄鳝生长最快,特定生长率分别为0.895和0.868%/d;DXS1与DXS2组稻田克氏原螯虾体质量增加率分别为(494.60±34.93)和(527.01±41.28)%,组间无显著差异(P>0.05),但均显著高于对照组(437.37±44.17)%(P<0.05)。在养殖效益方面,DX、DXS1和DXS2每667 m2平均利润分别为2165.8,2778.2和3172.3元。指出,在稻虾田中放养黄鳝虽然会减少水稻和克氏原螯虾的产量,但黄鳝的额外收入可显著提高经济效益。

To explore the influence of the stocking density of Monopterus albus on the water quality and comprehensive economic benefits of the rice shrimp farming field,the control group(DX)and two test groups(DXS1 and DXS2)were set up to conduct the breeding experiment,and the stocking quantity of Monopterus albus in three groups per 667 m~2 was 800 and 1600 ind.respectively.The results showed that the pH and PO43--P in the paddy water of the experimental group were not different from those of the control group(P>0.05),while NH3-N,NO2--N and TN were significantly higher than those of the control group(P<0.05),and the stocking of rice field eels contributed to the reduction of chemical fertilizer application in paddy fields.From May to September,the specific growth rates of rice field eels in DXS1 and DXS2 were(0.583±0.249)and(0.479±0.202)%/d,with the fastest growth rate of 0.895and 0.868%/d for eels in June;The gain rates of red swamp crayfish(Procambarus clarkii)in DXS1 and DXS2 groups were(494.60±34.93)and(527.01±41.28)%,respectively,there was no significant difference between the two groups(P>0.05),but they were significantly higher than those in the control group(437.37±44.17)%(P<0.05).The average profit of DX,DXS1 and DXS2 was 2165.8,2778.2 and 3172.3 yuan,respectively.In conclusion,the integrated Rice-Shrimp-Eel farming model has higher economic benefits than the Rice-Shrimp farming model.