基于表温的中西太平洋鲣栖息地适应指数的研究

The habitat suitability index of skipjack based on sea surface temperature in the western-central Pacific Ocean

根据1990—2001年中西太平洋海域(20°N^25°S,175°W以西)鲣Katsywonus pelamis围网作业产量和作业频次,结合海水表面温度(SST)数据,以高产频次的相对比值表示栖息地适应指数(HSI),采用3种方法建立HSI-SST模型。根据建立的3个模型,利用1990—2001年各月HSI值与实际作业产量进行比较,以选择最优HSI-SST模型;最后,利用2003年SST数据计算其各季度HSI值,用来验证预测中心渔场的可行性。结果表明:采用模型A时,主要产量分布在HSI>0.4的区域;采用模型B时,主要产量分布在HSI>0.6的区域;采用模型C时,主要产量分布在HSI>0.8的区域,因此认为模型C更符合鲣资源分布的特征。利用模型C估算2003年各季度HIS值,高产主要分布在HSI>0.8的区域,这进一步说明,模型C能较为准确地预报鲣中心渔场的位置。

The habitat suitability index （HSI） was estimated using the relative ratio of actual fishing times to maximum fishing times with monthly high yield according to the catch data and number of fishing in purse seine and the data of sea surface temperature （SST） in the western -central Pacific Ocean （20°N -25°S, 120°E -185°E） from 1990 to 2001. Firstly, three methods were used to establish the HSI model. Then, the models were tested and compared by overlaying the monthly catch and HSI spatial distribution to select the optimum HSI model. Finally, the optimum HSI model was used to forecast fishing ground based on the SST data in 2003. The results showed that the yield was mainly obtained in the area with HSI 〉 0.4 estimated by the model A, the area with HSI 〉 O. 6 esti- mated by the model B and the area with HSI 〉 0.8 estimated by model C. Therefore, the model C was the best which may be consistent with the skipjack distribution. The HSI in 2003 was estimated by model C, and the area with high yield was distributed in the region with HSI 〉 0.8, which further demonstrated the feasibility of forecasting fishing ground using the HSI model.