The original purpose of Vessel Monitoring System(VMS) is for enforcement and control of vessel sailing. With the application of VMS in fishing vessels, more and more population dynamic studies have used VMS data to im...The original purpose of Vessel Monitoring System(VMS) is for enforcement and control of vessel sailing. With the application of VMS in fishing vessels, more and more population dynamic studies have used VMS data to improve the accuracy of fisheries stock assessment. In this paper, we simulated the trawl trajectory under different time intervals using the cubic Hermite spline(c Hs) interpolation method based on the VMS data of 8 single otter trawl vessels(totally 36000 data items) fishing in Zhoushan fishing ground from September 2012 to December 2012, and selected the appropriate time interval. We then determined vessels' activities(fishing or non-fishing) by comparing VMS speed data with the corresponding speeds from logbooks. The results showed that the error of simulated trajectory greatly increased with the increase of time intervals of VMS data when they were longer than 30 minutes. Comparing the speeds from VMS with those from the corresponding logbooks, we found that the vessels' speeds were between 2.5 kn and 5.0 kn in fishing. The c Hs interpolation method is a new choice for improving the accuracy of estimation of sailing trajectory, and the VMS can be used to determine the vessels' activities with the analysis of their trajectories and speeds. Therefore, when the fishery information is limited, VMS can be one of the important data sources for fisheries stock assessment, and more attention should be paid to its construction and application to fisheries stock assessment and management.展开更多
971886 阿拉斯加楚科奇海东北部底层鱼类的集群=Demersal fish assemblages of thenor-theastern Chukchi Sea,Alaska[刊,英]/Barber W E,Smith R L,Vallarino M…//Fish.Bull..—1997,95(2).—195～209确证了1990年和1991年阿拉斯加楚...971886 阿拉斯加楚科奇海东北部底层鱼类的集群=Demersal fish assemblages of thenor-theastern Chukchi Sea,Alaska[刊,英]/Barber W E,Smith R L,Vallarino M…//Fish.Bull..—1997,95(2).—195～209确证了1990年和1991年阿拉斯加楚科奇海东北部底层鱼类的分布和丰度,并叙述了1990年底层鱼类的集群及其与该海域的一般海洋特点的关系。展开更多
Zhoushan fishery was once the biggest offshore fishery. for the winter season Trichiurus haumela in China, attracting thousands of fishermen and crowded by hundreds of fishing boats from all over the country every yea...Zhoushan fishery was once the biggest offshore fishery. for the winter season Trichiurus haumela in China, attracting thousands of fishermen and crowded by hundreds of fishing boats from all over the country every year. In order to fish Trichiurus haumela, the single trawl was innovated into the pair trawl, that is,展开更多
基金supported by the National Natural Science Foundation (No. 40801225)the Natural Science Foundation of Zhejiang Province (No. LY13D 010005)Young academic leader climbing program of Zhejiang Province (grant number pd 2013222)
文摘The original purpose of Vessel Monitoring System(VMS) is for enforcement and control of vessel sailing. With the application of VMS in fishing vessels, more and more population dynamic studies have used VMS data to improve the accuracy of fisheries stock assessment. In this paper, we simulated the trawl trajectory under different time intervals using the cubic Hermite spline(c Hs) interpolation method based on the VMS data of 8 single otter trawl vessels(totally 36000 data items) fishing in Zhoushan fishing ground from September 2012 to December 2012, and selected the appropriate time interval. We then determined vessels' activities(fishing or non-fishing) by comparing VMS speed data with the corresponding speeds from logbooks. The results showed that the error of simulated trajectory greatly increased with the increase of time intervals of VMS data when they were longer than 30 minutes. Comparing the speeds from VMS with those from the corresponding logbooks, we found that the vessels' speeds were between 2.5 kn and 5.0 kn in fishing. The c Hs interpolation method is a new choice for improving the accuracy of estimation of sailing trajectory, and the VMS can be used to determine the vessels' activities with the analysis of their trajectories and speeds. Therefore, when the fishery information is limited, VMS can be one of the important data sources for fisheries stock assessment, and more attention should be paid to its construction and application to fisheries stock assessment and management.
文摘971886 阿拉斯加楚科奇海东北部底层鱼类的集群=Demersal fish assemblages of thenor-theastern Chukchi Sea,Alaska[刊,英]/Barber W E,Smith R L,Vallarino M…//Fish.Bull..—1997,95(2).—195～209确证了1990年和1991年阿拉斯加楚科奇海东北部底层鱼类的分布和丰度,并叙述了1990年底层鱼类的集群及其与该海域的一般海洋特点的关系。
文摘Zhoushan fishery was once the biggest offshore fishery. for the winter season Trichiurus haumela in China, attracting thousands of fishermen and crowded by hundreds of fishing boats from all over the country every year. In order to fish Trichiurus haumela, the single trawl was innovated into the pair trawl, that is,
