摘要: |
通过人工围隔内伊乐藻种植区、无草区和围隔外湖区对照点的水质,底质定期观测,研究了伊乐藻对围栏养鱼环境的影响。结果表明:(1)围栏养鱼残饲和排泄物增加了水中N、P和COD含量,使DO与pH值降低,但伊乐藻对N的净化能力较强,使种植区TN和ION比无草区低14.5%和33.1%;(2)围栏养鱼对底泥的影响,无草区无明显变化,伊乐藻种植区养鱼前期N、P、C含量均低于本底值,养鱼后期有明显的增加趋势;(3)据N、P投入、输出计算,输出和迁移至伊乐藻与鱼体的大于投入的,计算表明,在伊乐藻生长旺季,养鱼与种植面积之比为1:3.58时,不会增加水中N、P含量。(4)养殖水体稀释扩散试验结果,在有草水体中围栏养殖水体对环境影响不大。 |
关键词: 伊乐藻 草鱼圈养 复合生态系统 水质 |
DOI:10.18307/1996.sup11 |
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Impacts of Elodea planting area on water environment of grass carp pen culture |
Chen Kaining
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Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008
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Abstract: |
Impacts of Elodea Nattalii on water quality of grass carp pen culture area were studied in man-made elodea-grass-carp compound ecosystem. The result shows that water in plantation was better than that in area of non-macrophyte. Content of TN and TP in water were not increased because of purification of Elodea in planted area. By estimated balance of nitrogen and phosphorus in plantation, the appropriate of pen culture area to planted elodea area is 1:3.58. In addition, it was only partitive that breeded fish effected water quality in weeds-filled water body. So far as whole area of planted, there was little influence on water quality. |
Key words: Elodea grass carp pen culture compound ecosystem water quality |