The Research Of Carrying Capacity Of Shellfish In The Jiaozhou Bay

The Jiaozhou Bay is the important basement of shellfish in the northern. There two aquaculturing methods in the bay: benthic aquaculturing is for Ruditapes philippinarum and suspended aquaculturing is for scallop .The aquaculturing areas of Ruditapes philippinarum have reached 150,000 acres and amount to 70% of all aquaculture in the Jiaozhou Bay. The annual production is 300,000t and is amount to 95% of annual production of Jiaozhou Bay. In the recent years, the culturing condition of shellfish in the Jiaozhou Bay has been saturated, and mortality has rised severely. So we calculate the carrying capacity model for shellfish in the Jiaozhou Bay basing on the plankton ecosystem dynamic model. The model considers physical impacts of water temperature, sun light and river input and so on, including the state variables of phytoplankton, zooplankton, shellfish and nutrient.We calculate the carrying capacity of the Ruditapes philippinarum in the Jiaozhou Bay basing on the ecosystem dynamic model. The smallest carrying capacity of Ruditapes philippinarum of shell length of 2.0-2.6cm in Hongdao eastern area, Hongdao southern area, Hongdao western area, Jiaozhou area, Huangdao area are 664 ind/m~2,653 ind/m~2,517 ind/m~2,746 ind/m~2,605 ind/m~2. The smallest carrying capacity of Ruditapes philippinarum of shell length of 2.6-3.3cm in Hongdao eastern area, Hongdao southern area, Hongdao western area, Jiaozhou area, Huangdao area are 492 ind/m~2,485 ind/m~2,383 ind/m~2,554 ind/m~2,449 ind/m~2. The smallest carrying capacity of Ruditapes philippinarum of shell length of 3.3-4.0cm in Hongdao eastern area, Hongdao southern area, Hongdao western area, Jiaozhou area, Huangdao area are 402 ind/m~2,378 ind/m~2,312 ind/m~2,451 ind/m~2,366 ind/m~2. Comparing the production and benefit of the culturing body size of 2.6~3.3cm(2 ages) and culturig body size of 3.3~4cm(3 ages), find that culturing 3 ages getting more benefit. We suggest the infancy Ruditapes philippinarum density of Hongdao eastern area, Hongdao southern area, Hongdao western area, Jiaozhou area, Huangdao area are 574 ind/m~2,540 ind/m~2,446 ind/m~2,644 ind/m~2,523 ind/m~2,and harvest after two years culturing.The annual smallest carrying capacity for scallop appears september. The smallest carrying capacity of scallop of shell length of 3-4cm in Hongdao eastern area, Hongdao southern area, Hongdao western area are 66 ind/m~2,56 ind/m~2,56 ind/m~2. The smallest carrying capacity of scallop of shell length of 4-5cm in Hongdao eastern area, Hongdao southern area, Hongdao western area are 46 ind/m~2,38 ind/m~2,38 ind/m~2. The smallest carrying capacity of scallop of shell length of 5-6cm in Hongdao eastern area, Hongdao southern area, Hongdao western area are 36 ind/m~2,30 ind/m~2,30 ind/m~2. We suggest the infancy scallop density of Hongdao eastern area, Hongdao southern area, Hongdao western area are 209 ind/cage, 174 ind/cage, 174 ind/cage and 27 ind/floor, 22 ind/floor, 22 ind/floor.