养鳗池塘的初级生产力和能量转换效率

报道了养鳗池塘初级生产力的垂直变化和季节变化。养鳗池塘的初级生产量为 3.5 1～ 7.90gO2 /m2 ·day ,高峰通常出现在 7～ 8月。 1米以上水层的光合作用产氧量占水柱总产量的 90 %以上。平均补偿深度为 6 5～ 74cm。池水氧气的消耗 ,池鱼占 2 7.4% ,“水呼吸”占 70 .0 % ,底泥占 3.6 %。浮游植物光合产氧占池塘氧气来源的 6 6 .0 % ,余下的 43.0 %靠空气和加水补给。毛初级生产力对太阳辐射能的利用率为 0 .38%～ 0 .85 % ;鳙产量对浮游植物的利用率为 1 .0 5 %～ 2 .32 % ;太阳能转移为鱼产量的生态学效率为 0 .0 0 9%～ 0 .0 1 0 %。

Primary productivity and energy conversion efficiency in eel pond

The vertical and seasonal changes of primary productivity in eel ponds were reported in this paper. The gross oxygen production in water column in eel ponds ranged 3. 51- 7. 90 g O2/ m2..day and the peak appeared in July to August. The photosynthetic oxygen production one meter or less below the water surface accounted for over 90% of the total production. The average compensation depth was 65- 74cm. Among the total oxygen consumption, fish occupied 22. 4%, .. water respiration.. 71. 3%, and detritus 6. 4% respectively. The oxygen production by photosynthesis accounted 67. 7% of the oxygen resources of eel ponds, the rest was supplied by air- dissolved and water- f illing. The photosynthetic energy effciency reached 0. 38% - 0. 85% of solar radiation. The efficiency of converting phytoplankton production to the yield of big- head carp was 1. 05% - 2. 32% and the ecological eff iciency of converting solar radiation to f ish production was 0. 009%- 0. 010% .