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为建立稳定环境和波动环境机制下预防性渔业管理生物参考点,整合调查设计和渔捞日志等多源资源指标构建混合矩阵,利用logistic和Fox剩余产量模型的两步分析技术,对东海区小黄鱼(Larimichthys polyactis)渔业资源动态进行评估。模型估算参数和管理参考点显示,Fox模型对渔获量和CPUE拟合的方差贡献率高于logistic模型,两者分别为68%和57%,环境承载力和内禀增长率相差较大。logistic模型估算了相对较低的承载力和较高的内秉增长率、初始开发率以及MSY。稳定环境下资源状况评判结果表明:1999―2008年间多数年份的捕捞强度超过捕捞水平限制参考点,渔业遭受过度开发,平均资源量保持在中位水平且未达到过度捕捞状态,但已超过目标参考点;波动环境条件下的判别结果显示:logistic和Fox模型拟合的渔业水平均已达到过度捕捞。采用保护性捕捞参考点可增强渔业资源稳定性,当捕捞死亡从参考点FMSY降至预防性参考点Fopt,logistic模型估算资源量从8.1 t上升到10.1 t,而渔获量从13.1 t下降至12.3 t;Fox模型资源量则从11 t增加到15.9 t,相应的捕捞产量从12.8 t下降到11.6 t。Fox模型评估结果较为保守,适合预防性渔业管理。
In order to establish a hybrid matrix for multi-source resource indicators such as biological reference point for preventive fishery management in a stable environment and fluctuating environment, integrated survey design and fishery log, and using the two-step analysis technique of logistic and Fox residual yield models, (Larimichthys polyactis) fisheries resources dynamic assessment. Model estimation parameters and management reference points show that the contribution of Fox model to catch and CPUE variance is higher than that of logistic model, both of them are 68% and 57% respectively, and the difference between environmental carrying capacity and intrinsic rate of increase is large. The logistic model estimates relatively low bearing capacity and high intrinsic growth rate, initial development rate, and MSY. The results of resource status assessment in stable environment showed that the fishing intensity in most years between 1999 and 2008 exceeded the reference point of fishing level restriction, the fishery was over-developed, the average resource remained at the middle level and did not reach the over-fishing status, but exceeded the target reference Point; under the fluctuating environmental conditions, the discrimination results show that: the logistic and Fox models fit the fishery level have reached over-fishing. The use of protective reference points for fishing can increase the stability of fishery resources. When the fishing death drops from the reference point FMSY to the preventive reference point Fopt, the logistic model estimates that the resource amount increases from 8.1 t to 10.1 t, while the catch decreases from 13.1 t to 12.3 t; Fox model resources increased from 11 t to 15.9 t, and corresponding fishing output decreased from 12.8 t to 11.6 t. Fox model evaluation results are more conservative, suitable for preventive fishery management.