GIS analysis on effect of temporal and spatial patterns of marine environment on purse seine fishery in the western and central Pacific

According to the fishery production data of the western and central Pacific tuna purse seine from 2008 to 2012, in addition to the main marine environmental datasuch as sea surface temperature, subsurface and thermocline temperature and chlorophyll obtained by remote sensing trchnolongy, we analyzed the relationship between fish catches of themain purse seine species, resource abundance, time-space changes of fishing ground gravity and the main environmental factors. Results show that tuna purse seine catches distributed in the western and central Pacific from 10 N to 10 S and 140 E to 180 E. The longitude of fishing ground gravity concentrated from 150 E to 165 E from west to east. Latitude center concentrated from 1 N to 3 S and presented in the direction of north after south. The optimum temperature for fishing ground ranged from 28 ℃ to 32 ℃, the best sea surface temperature ranged from 29 ℃ to 31 ℃. The suitable temperatures at subsurface depths of 50 m and 100m were 26.84 ~26.84 ℃ and 24.71~24.71 ℃, respectively. The upper and lower bound of the thermocline depth was 54.09~121.49 m,and the corresponding seawater temperature was 27.10~29.18 ℃. The main fishing production distributed in chlorophyll concentration of 0.02~0.35 mgm-3. Thehighest frequency occurred in chlorophyll concentration of 0.04~0.18 mgm-3which was the most appropriate chlorophyll concentration range for fishing ground.