虾池中日本刺沙蚕的次级生产力研究

１９９１－１９９２年的５－８月，在辽宁省庄河市总面积４０．１３公顷的六座虾池用Ａｌｌｅｎ和Ｇｒａｙ法估算了日本刺沙蚕总生产量。Ｇｒａｙ法表明，六座虾池沙蚕总生产量平均为４７４．２９（２４０．０１－７９１．０７）ｇ／ｍ＾２；Ｐ／Ｂ系数平均是６．４４（５．４４－７．４４）。在虾池中，沙蚕与对虾间的生产效率平均约为１３（１２－１４．５）。回归分析表明，影响虾池沙蚕生产量的主要因素是沙蚕生物量与水温的交互

Secondary production of Neanthe japonica in shrimp ponds

The gross production of Neanthe Japonica (Polychaeta: Nereise) in shrimp ponds was studied from March to August, 1991-1992. The results showed that the reproduction of Neathe japonica occured form March to June with a peak in April. The initial numbers varied from 1341 to 22055 individuals/m2. The mean standing stock was between 32. 26-145. 48 g/m2, with a mean of 77. 72 g/m2. The gross production was fluctuated between 240. 01 to 791. 07 g/m2 which was calculated by the relationship between mean weight increment of individuals and survival numbers per m2, in The population. P/B-ratio was from 5. 44-7. 44. The results of regression analysis showed that the major facts affecting the production of sandwom were: biomass itself, the interaction between the biomass and the temperature, the interaction between the phytoplankton and pH and between the salinity and the initial larva numbers in ponds. It was clear that present of shrimp predators was the main reason for the decrease of sandworm population. It was estimated that about 20% production of shrimp was from the sandworm production.