不同单养和混养海水实验围隔初级生产力的研究

STUDIES ON PRIMARY PRODUCTION IN SEAWATER EXPERIMENTAL ENCLOSURES WITH DIFFERENT MONOCULTURE OR POLYCULTURE

1995年和 1996年夏秋季进行的围隔实验表明投饵养殖时浮游植物毛初级生产力较低 ,水呼吸相对较高 ,多数围隔中毛初级生产力 /水呼吸 <1,其中混养中国对虾和台湾红罗非鱼的围隔中毛初级生产力较高 ,而混养中国对虾、台湾红罗非鱼和菲律宾蛤仔的围隔中毛初级生产力最低 ;在投饵基础上酌情施肥后围隔毛初级生产力明显高于投饵养殖时 ,毛初级生产力 /水呼吸 >1,但单养中国对虾、对虾与罗非鱼混养和对虾与海湾扇贝或缢蛏混养的围隔间毛初级生产力差别不明显。实验结果显示 ,养殖管理措施、放养的罗非鱼和贝类以及附生的丝状藻类都能对围隔初级生产力产生一定的影响 ,其中管理措施往往起到较重要的作用。

The result of enclosure experiment carried out from summer to autumn in 1995 and 1996. It showed that during feeding period the gross primary production of phytoplankton (PPGP) was lower and respiration of water column (WR) relatively higher, in most enclosures PPGP/WR<1 , the PPGP in enclosures polycultured shrimps and a hybrid tilapia was higher, in opposite, the enclosure polycultured shrimps, tilapia and Ruditapes Philippinarum had the lowest PPGP. When suitable fertilization was adopted on the basis of daily feeding, PPGP in experimental enclosures was significantly higher than that as only feeding was adopted, PPGP/WR>1 , but there was not apparent difference in PPGP between enclosure monocultured shrimps, polycultured shrimps and tilapia, polycultured shrimps and bay scallop, and polycultured shrimps and Sinonvacula constricta. These results indicate that the cultural management measures, routine feeding and fertilization, stocked tilapia and bivalve and periphery algae all affect the gross primary production in enclosures, in which management measures usually play an important role.