太湖银鱼资源变动关联因子及资源测报方法探讨

据１９８９￣１９９４年汛期前后测试结果，结合实际产量，运用灰色系统理论关联方法，得知与银鱼资源密切相关因子是水位和捕捞强度。汛后留湖量与捕捞强度呈负相关，秋汛银鱼产量与春汛留湖量呈指数回归，与太湖新银鱼春群留湖数量呈线性相关。

A study on the factors affecting icefish resource and the forecasting of the resources

During the peyiod of 1989 to 1994, the relevant factors were measured periodicallybefore and after fishing seasons. The analysis by applying grey system theory and man-made nervousnetwork techniques combining with the actual production indicates the main factors correlated withicefish resources were the water level and the fishing intensity. The correlation between the biomassremaining after fishing seasons and the fishing intensity appeared negative. This quantitative analysisshows that the icefish production in autumn season was in exponential regression with the biomassremaining in spring season (r=0.989 5) was in linear correlation with the remaining biomass ofspring population of Neosalanx taihunensis (r=0.9640). The study indicates that the predator-preyrelationships made the autumn population of icefish Neosslanx taihunensis in negative exponentialcorrelation with large icefish Protosalanx hyalocranius (r=-0.826 7). On the basis of test-fishing,actual production and remaining biomass, the harvestable biomass forecasting systems have beenpreliminarily set up for icefish in two seasons with forecast.