对虾、青蛤和江蓠混养系统氮磷收支的实验研究

An Experimental Study on Nitrogen and Phosphorus Budgets in Polyculture of Shrimp,Bivalve and Seaweed

为减少养殖污水中营养盐的排放量，降低对近海水质的污染，采用海水陆基围隔实验法，对凡纳滨对虾（Litopenaeus vannamei）、青蛤（Cyclina sinesis）和菊花心江蓠（Gracilaria lichevoides）不同混养系统的氮（N）、磷（P）收支状况进行了实验研究。结果表明：实验中的单养组投放的饵料占N总输入的75．5％，占P总输入的93．6％，混养组投放的饵料占N总输入的54．7％～64．8％，占P总输入的81．6％～88．7％；在支出项目中，单养组和混养组收获的养殖生物分别占N总输入的25．0％和44．4％～51．5％，占P总收入的11．2％和25．1％～31．8％；底泥沉积N，P为其主要支出项目。单养组和混养组分别占总输入的45，1％和30．0～32．5％，68．3％和50．3％～57．1％，其中混养组N，P的底泥沉积量低于单养组。

The budgets of nitrogen （N） and phophorus （P） in different polyculture systems, in which Litopenaeus vannamei were polycultured with Cyclina sinesis and Gracilaria lichevoides, were studied with landbased enclosures. It is shown that the shrimp feed accounted for 75.5 % nitrogen and 93.6 % phosphorus of the total inputs in monoculture systems while, 54.7 % - 64.8 % nitrogen and 81.6 % - 88.7 % phosphorus in polyculture systems; Among the output items, the biomass harvest comprised 44.4 % - 51.5 % of total nitrogen input and 25.1% - 31.8 % of total input phosphorus in polyculture systems, 25.0 % and 11.2 % for monoculture systems; The major outputs of nitrogen and phoshorus were in the sediments, which accounted for 30.0% 32.5% of total nitrogen inputs and 50.3% - 57.1% of total phosphorus inputs in polyculture systems and 45.1% and 68.3% in monoculture systems, nitrogen and phoshorus deposited in the sediments of polyculture systems were lower than those in monoculture systems.