闽中渔场鱼类资源生产量和最大可持续开发量

The production of fishery resources and the maximum sustained yield in the Min-zhong fishery in Taiwan Strait

以海洋生态系统营养动力学为理论依据，依据历次台湾海峡海洋科学调查在闽中渔场所获得的初级生产力为基础，通过2000～2001年对该渔场的浮游植物有机碳含量和生态效率及61种主要经济鱼类的营养级，58种主要鱼类有机碳含量的调查、检测，采用营养动态模型和Cushing模型估算鱼类资源生产量；进而采用Cadima模式和剩余产量模式估算鱼类资源最大可持续开发量。估算结果：营养动态模型估算鱼类资源潜在生产量为38．59×10^4 t，Cushing模型估算为43．68×10^4 t；Cadima模式估算最大可持续开发量为25．32×10^4 t；Schaefer和Fox模式估算最大可持续开发量分别为23．96×10^4 和25．28×10^4 t，估算的最大持续捕捞力量换算为以福建单拖渔船艘为标准分别为3372和3983艘；1994年以来实际年渔获量在27．00×10^4 ～40．01×10^4 t，实际捕捞力量在3897～5967艘标准单拖渔船，已连续11年超过了鱼类资源最大可持续开发量和鱼类资源可承载的最大持续捕捞力量。主要鱼类种群结构出现简单化、小型化和低龄化，生态学参数渐近体长L∞和渐近体重形。趋小，个体生长速率K加大，体重生长拐点tr提前，初次性成熟年龄提早，捕捞死亡系数提高和开发比率上升，资源明显衰退。必须加强对该渔场鱼类资源的管理，采取有力措施控制捕捞力量的投入和渔获量的产出，以防鱼类资源进一步恶化。

In this paper, according to the theory of marine ecosystem trophic dynamic, based on the primary productivity data of the Min-zhong Taiwan Strait collected from the marine science surveys in the Taiwan Strait, by investigation of the species composition and structure of fishery resource, the content of organic carbon in phytoplankton, ecological efficiency, the trophic levels of the 61 main species, and measuring the content of organic carbon of the 58 main species. The trophic dynamic model and Cushing＇ model are used to estimate the productivity of fishery resources, the trophic dynamic model and surplus yield model are used to estimate the maximum sustained yield of fishery resources. The result shows that the potential productivity of fishery resources is calculated using trophic dynamic model and Cusing model to be 38.59 × 10^4 and 43.68 × 10^4 t, respectively. The maximum sustained yield （MSY） of fishery resources is calculated using Cadima model, Schaefer and Fox model to be 25.32 × 10^4 , 23.96 × 10^4 and 25.28 × 10^4 t, respectively. The maximum sustained effort is calculated using Schaefer and Fox model to be 3 372 and 3 983 of standard trawl boats in Fujian. The annual catches have been among 27.00 × 10^4 -40. 01 × 10^4 t since 1994, and the devoted fishing efforts are 3 897 -5 976 of standard trawl boats in Fujian, which have exceeded the maximum sustained yield and the maximum sustained efforts for 11 years. The fishes＇ structure of the main population is simplification, miniaturization and younger. The ecological parameters of utmost length （L∞） and utmost weight （ W∞ ） are smaller, the growth curvature （K） is increasing, the inflexion of weight （tr） is ahead the schedule, the length of the first maturity is shorter, the fishing mortality coefficient and the ratio of exploitation are increasing, so the fishery resources decline rapidly. We must intensify the management of the fish resources, and take powerful measures to control the fishing effort and catches.