稻虾专用青苔净对小龙虾的急性毒性和对青苔生长的影响

Researches on the Acute Toxicity Effect in the Crayfish Procambarus Clarkii and Control Effect of Moss-Cleaner for Rice-Crayfish Complex Culture

为了解稻虾专用青苔净对小龙虾的急性毒性和对青苔生长的影响。进行了青苔净对小龙虾的急性毒性试验。结果表明,青苔净对小龙虾24 h和48 h的半致死浓度均高于1000 mg/L,在72 h和96 h对小龙虾的半致死浓度分别为327.73,78.14 mg/L;稻虾专用青苔净对青苔杀灭效果明显,5,10,20和40 mg/L处理组的平均青苔质量分别为3.60,2.60,2.10和0.67 kg,均显著低于空白对照组(P<0.05);施用稻虾专用青苔净后,随着养殖时间的增加,水体溶解氧总体呈下降趋势,且处理组的波动幅度较对照组的要大。在青苔净施用初期,水体pH值略有降低,但与对照组相比变化不大;随着试验时间的增加,水体pH值逐步增加,但处理组的波动幅度略为平缓。

This article aimed to study the acute toxicity of moss-cleaner for Procambarus clarkii and its effect on the growth of moss in rice-shrimp complex culture farm. The experimental results showed that when the moss-cleaner is used for 24 h and 48 h, the half-lethal concentration of crayfish was higher than 1 000 mg/L,and when the use time reached 72 h and 96 h, the half-lethal concentration of crayfish was 327.73 mg and 78.14 mg, respectively. The experimental results showed that the moss-cleaner had a significant effect on eliminating moss. The average moss weight of 5, 10, 20 and 40 mg/L treatment groups were 3.60, 2.60, 2.10 kg and 0.67 kg respectively, which were significantly lower than that of the blank(P<0.05). After the moss-cleaner used, the dissolved oxygen in the water body showed an overall downward trend with the increase of breeding time, and the fluctuation range of the treatment group was larger than that of the control group.The pH decreased slightly at the initial stage of the application of the moss-cleaner, but all groups had no change between each other. With the continuation of the breeding experiment, the pH value of the water body increased gradually, but the fluctuation range of the treatment group was slightly flat.