中华鳖不同生态养殖模式对池塘水环境及养殖效果的影响

Effects of Different Culturing Modes on Pond Environment and Output of Trionyx sinensis

利用条件相近的两组池塘,对中华鳖(Trionyx sinensis)的两种生态模式(Ⅰ组:中华鳖-吃食性鱼类鲤和草鱼模式;Ⅱ组:中华鳖-杂食性水生动物鲫和螺模式)对池塘水环境以及养殖效果的影响进行对比试验。结果表明,Ⅱ组CODMn在7、8、和9月显著低于Ⅰ组(P<0.05),NH3在6、7、8和9月显著低于Ⅰ组(P<0.05),TP在7月和8月显著低于Ⅰ组(P<0.05),TN在6、7和8月显著低于Ⅰ组(P<0.05),NO2--N在6月和7月显著低于Ⅰ组(P<0.05),Ⅱ组水环境质量较Ⅰ组好。Ⅱ组检出藻类47种,Ⅰ组34种,Ⅱ组种类显著增多(P<0.05);Ⅰ组蓝藻重量占83.18%,硅藻2.98%,隐藻2.65%,甲藻0%,Ⅱ组蓝藻58.59%,硅藻13.44%,隐藻14.00%,甲藻7.07%,Ⅱ组蓝藻明显下降,而硅藻、隐藻、甲藻明显上升(P<0.05)。6月Ⅰ组平均生物量4.18mg/L,Ⅱ组2.57mg/L,8月Ⅰ组29.04mg/L,Ⅱ组5.41mg/L,6月和8月Ⅰ组生物量均显著高于Ⅱ组(P<0.05)。Ⅰ组Shannon-Wiener指数H'在6月和8月均值分别为2.117和0.7467,Ⅱ组均值分别为2.5427和1.0178,Ⅱ组6月和8月H'均明显增加(P<0.05);在6月,Ⅱ组Margalef丰富度指数d为1.8516,Ⅰ组为1.2499,Ⅱ组较Ⅰ组上升明显(P<0.05);两组的Pielou匀度均指数J差别不大。Ⅱ组中华鳖平均产量11782.5kg/hm2,显著高于Ⅰ组11482.5kg/hm2(P<0.05)。

The effects of two ecological modes （group I： Trionyx sinensis and predatory fishes-cyprinoid and grass carp; group II：Trionyx sinensis and omnivore aquatic animals-crucian and conch） on pond environment and output of Trionyx sinensis was studied under two pond groups with similar environment. In terms of the physical-chemical factors of water quality, CODMn in group II was significantly lower than that in group I from July to September （ P 〈 0.05 ） ; NH3 was significantly lower than that in group I from June to September（ P 〈 0.05 ） ; TP was significantly lower than that in group I in July and August（P 〈 0.01 ） ; TN was significantly lower than that in group I from June to August （ P 〈 0.05 ） ; NO2-N was significantly lower than that in group I in June and July （ P 〈 0.05 ）. Phytoplankton community increased significantly in group II with 47 algae, while 34 algae in group I. The weight of Cyanophyta, Bacillariophyceae, Cryptophyta and Pyrrophyta in group I accounted for 83. 18% ,2.98% ,2.65% and 0%, respectively; while it was 58.59%, 13.44%, 14.00% and 7.07% in group II, respectively, with Cyanophyta decreasing significantly and the other three algae increasing significantly （ P 〈 0.05 ）. The average biomass was 4.18 mg/L in group I while 2.57 mg/L in group II in June, and it was 29.04 mg/L in group I while 5.41 mg/L in group II in August. The biomass was higher in group I than that in group II in both months （ P 〈 0.05 ）. In terms of biodiversity index, the Shannon-Wiener index was 2.117 and 0. 7467 in group I in June and August, while it increased significantly to 2. 5427 and 1. 0178 separately in group II in both months （P 〈0.05 ）. The Margalef richness index was 1. 8516 in group I and 1. 2499 in group II. It increased significantly in group II than that in group I （P 〈 0.05 ）. The Pielou evenness index showed little change. The average output of Trionyx sinensis in group II was 11782. 5 kg/hm2, which was significantly higher than that in group I with 11482.5 kg（P 〈0.05）.