Age, maturation and population structure of the Humboldt squid Dosidicus gigas were studied based on random sampling of the Chinese jigging fishery off the Peruvian Exclusive Economic Zones （EEZ） during 2008-2010. E...Age, maturation and population structure of the Humboldt squid Dosidicus gigas were studied based on random sampling of the Chinese jigging fishery off the Peruvian Exclusive Economic Zones （EEZ） during 2008-2010. Estimated ages ranged from 144 to 633 days, confirming that the squid is a short-lived species with longevity no longer than 2 years. Occurrence of mature females and hatching in each month indicated that Humboldt squid spawned year-round. Back-calculated hatching dates for the samples were from January 22^nd, 2008 to April 22nd, 2010 with a peak between January and March. Two size-based and two hatching date-based populations could be defined from mantle length （ML） at maturity and back-calculated hatching dates, respectively. Females matured at a larger size than males, and there was a significant difference in ML at maturity between the two hatching groups （P〈0.05）. The waters adjacent to 1 l^S off the Peruvian EEZ may be a potential spawning ground. This study shows the complexity of the population structure and large variability in key life history parameters in the Humboldt squid off the Peruvian EEZ, which should be considered in the assessment and management of this important resource.展开更多
Although many studies on the fishery biology of jumbo flying squid, Dosidicus gigas, have been conducted in the coastal areas within Exclusive Economic Zones （EEZs） of various countries due to its commercial and eco...Although many studies on the fishery biology of jumbo flying squid, Dosidicus gigas, have been conducted in the coastal areas within Exclusive Economic Zones （EEZs） of various countries due to its commercial and ecological importance, limited biological information is available from waters outside these EEZs. In this paper, we examined D. gigas fishery biology from waters outside Chilean, Peruvian and Costa Rican EEZs, based on the fishery data collected by Chinese jigging vessels during 2006 to 2010. The dominant mantle lengths olD. gigas were 350-450 mm, 250-400 mm and 250-350 mm outside Chilean, Peruvian and Costa Rican EEZs, respectively. Size structure analysis show that a medium-sized group existed mostly in the waters outside the Chilean and Peruvian EEZs, whereas a small-sized group occurred mainly in the waters outside the Costa Rican EEZ. The longevity of the squid outside the Costa Rican EEZ was less than 10 months, while most of those outside Chilean and Peruvian EEZs were about 1-1.5 years and very few large individuals were 1.5-2 years old. A higher percentage of mature individuals existed outside Costa Rican EEZ implying the region as a potential spawning ground, while lower proportions of mature squid outside the Peruvian and Chilean EEZs indicated that spawning may be occurring outside our study area. Spatial differences in sizes at maturity of the squid are thought to be result from different environmental factors especially different temperature and nutrition among the three areas. Stomach-content analysis showed that cannibalism was important in the diet of D. gigas. Stress generated by jigging may increase the incidence of cannibalism.展开更多
JOGMEC （Japan Oil, Gas and Metals National Corporation） has conducted exploration and research in Japan＇s EEZ （exclusive economic zone） from fiscal year 2008, under contract by the METI （Ministry of Economy, Tra...JOGMEC （Japan Oil, Gas and Metals National Corporation） has conducted exploration and research in Japan＇s EEZ （exclusive economic zone） from fiscal year 2008, under contract by the METI （Ministry of Economy, Trade and Industry）, for the commercialization of SMS （Seafloor Massive Sulfide）. As there is currently no commercial mining precedent of SMS, it is necessary to consider the potential impacts of mining on the surrounding environment, and to promote long term sustainable projects. In particular, due to the existence of specific chemosynthetic ecosystems and unique biological communities around the SMS area, both quantitative evaluations of potential environmental impacts and consequent environmental conservation strategies, are necessary in order to avoid and or minimize the potential detrimental effects to the ecosystem, as much as possible. The environmental research programs consist of baseline surveys, environmental impact modeling, and methodological concepts which will be applied to conserve biodiversity. In this paper, we will primarily provide an overview of the project conducted by JOGMEC during 2008-2012.展开更多
Knowledge of the biodiversity of Brazilian reef ecosystems has expanded in recent years with several new species. Brazil is considered an important province because it has the only true reefs in the South Atlantic. Th...Knowledge of the biodiversity of Brazilian reef ecosystems has expanded in recent years with several new species. Brazil is considered an important province because it has the only true reefs in the South Atlantic. This study identified the endemism of benthic invertebrate species of the Brazilian reefs. The reef coast is approximately 600 km long and extends from the state of Rio Grande do Norte to south coast of the Bahia state, with many coral and sandstone reefs near the shoreline and in the offshore zone, where the platform top remains exposed during low tides; and also on the Abrolhos region has isolated columns and offshore banks. Four offshore sites within the EEZ （Exclusive Economic Zone） were also included in this review. This study was based on the invertebrate benthic diversity existing on the northeastern coast, represented by Porifera with 450 spp, Cnidaria Scleractinia 16 spp and Echinodermata 51 spp. Of these, 102 species are endemic to Brazilian reefs, including Porifera with 86 spp （18,44%）, Cnidaria Scleractinia 8 spp （50%）, and Echinodermata 8 spp （2.93%）. The results reflect the recent increase in taxonomic studies, and identify a large number of endemic species among the benthic invertebrate fauna of the Brazilian reefs.展开更多
The marine area of Japan, including territorial waters and the exclusive economic zone, is the sixth largest in the world at about 4,470,000 km2. Therefore, it is becoming necessary to establish appropriate means of t...The marine area of Japan, including territorial waters and the exclusive economic zone, is the sixth largest in the world at about 4,470,000 km2. Therefore, it is becoming necessary to establish appropriate means of transportation other than ships in order to utilize the area efficiently. In this respect, ultra-light seaplanes are attracting attention from the viewpoint of protecting the natural environment. Accordingly, JRPS （Japan Reinforced Plastics Society） is currently developing FRP （fiber-reinforced plastic） floats for such planes. In this study, we conducted simulations of seaplane behavior during alighting by using the smoothed particle hydrodynamics method, which is one of the functions in the PAM-CRASH solver, and we present the observed trend in the vertical acceleration of the floats as a first step toward deriving the impact force from analytical data.展开更多
基金Supported by the National Natural Science Foundation of China (No.41276156)the National High Technology Research and Development Program of China (863 Program) (No. 2012AA092303)+3 种基金the Innovation Program of Shanghai Municipal Education Commission (No. 13YZ091)Shanghai Leading Academic Disciplin Projectsupported by National Distant-Water Fisheries Engineering Research Center, and Scientific Observing and Experimental Station of Oceanic Fishery Resources, Ministry of AgricultureYong Chen’s involvement in the project was supported by the Shanghai Dongfang Scholar Program
文摘Age, maturation and population structure of the Humboldt squid Dosidicus gigas were studied based on random sampling of the Chinese jigging fishery off the Peruvian Exclusive Economic Zones （EEZ） during 2008-2010. Estimated ages ranged from 144 to 633 days, confirming that the squid is a short-lived species with longevity no longer than 2 years. Occurrence of mature females and hatching in each month indicated that Humboldt squid spawned year-round. Back-calculated hatching dates for the samples were from January 22^nd, 2008 to April 22nd, 2010 with a peak between January and March. Two size-based and two hatching date-based populations could be defined from mantle length （ML） at maturity and back-calculated hatching dates, respectively. Females matured at a larger size than males, and there was a significant difference in ML at maturity between the two hatching groups （P〈0.05）. The waters adjacent to 1 l^S off the Peruvian EEZ may be a potential spawning ground. This study shows the complexity of the population structure and large variability in key life history parameters in the Humboldt squid off the Peruvian EEZ, which should be considered in the assessment and management of this important resource.
基金Supported by the National Natural Science Foundation of China(No.NSFC41276156)Innovation Program of Shanghai Municipal Education Commission(No.13YE091)+5 种基金Industrialization Project of National Development and Reform Commission(No.2159999)Project of Shanghai Science and Technology Commission(No.12231203900)National High Technology Research and Development Program of China(863 Program)(No.2012AA092303)Shanghai Leading Academic Discipline Project(Fisheries Discipline)National Distant-Water Fisheries Engineering Research Centerthe Scientific Observing and Experimental Station of Oceanic Fishery Resources,Ministry of Agriculture
文摘Although many studies on the fishery biology of jumbo flying squid, Dosidicus gigas, have been conducted in the coastal areas within Exclusive Economic Zones （EEZs） of various countries due to its commercial and ecological importance, limited biological information is available from waters outside these EEZs. In this paper, we examined D. gigas fishery biology from waters outside Chilean, Peruvian and Costa Rican EEZs, based on the fishery data collected by Chinese jigging vessels during 2006 to 2010. The dominant mantle lengths olD. gigas were 350-450 mm, 250-400 mm and 250-350 mm outside Chilean, Peruvian and Costa Rican EEZs, respectively. Size structure analysis show that a medium-sized group existed mostly in the waters outside the Chilean and Peruvian EEZs, whereas a small-sized group occurred mainly in the waters outside the Costa Rican EEZ. The longevity of the squid outside the Costa Rican EEZ was less than 10 months, while most of those outside Chilean and Peruvian EEZs were about 1-1.5 years and very few large individuals were 1.5-2 years old. A higher percentage of mature individuals existed outside Costa Rican EEZ implying the region as a potential spawning ground, while lower proportions of mature squid outside the Peruvian and Chilean EEZs indicated that spawning may be occurring outside our study area. Spatial differences in sizes at maturity of the squid are thought to be result from different environmental factors especially different temperature and nutrition among the three areas. Stomach-content analysis showed that cannibalism was important in the diet of D. gigas. Stress generated by jigging may increase the incidence of cannibalism.
文摘JOGMEC （Japan Oil, Gas and Metals National Corporation） has conducted exploration and research in Japan＇s EEZ （exclusive economic zone） from fiscal year 2008, under contract by the METI （Ministry of Economy, Trade and Industry）, for the commercialization of SMS （Seafloor Massive Sulfide）. As there is currently no commercial mining precedent of SMS, it is necessary to consider the potential impacts of mining on the surrounding environment, and to promote long term sustainable projects. In particular, due to the existence of specific chemosynthetic ecosystems and unique biological communities around the SMS area, both quantitative evaluations of potential environmental impacts and consequent environmental conservation strategies, are necessary in order to avoid and or minimize the potential detrimental effects to the ecosystem, as much as possible. The environmental research programs consist of baseline surveys, environmental impact modeling, and methodological concepts which will be applied to conserve biodiversity. In this paper, we will primarily provide an overview of the project conducted by JOGMEC during 2008-2012.
文摘Knowledge of the biodiversity of Brazilian reef ecosystems has expanded in recent years with several new species. Brazil is considered an important province because it has the only true reefs in the South Atlantic. This study identified the endemism of benthic invertebrate species of the Brazilian reefs. The reef coast is approximately 600 km long and extends from the state of Rio Grande do Norte to south coast of the Bahia state, with many coral and sandstone reefs near the shoreline and in the offshore zone, where the platform top remains exposed during low tides; and also on the Abrolhos region has isolated columns and offshore banks. Four offshore sites within the EEZ （Exclusive Economic Zone） were also included in this review. This study was based on the invertebrate benthic diversity existing on the northeastern coast, represented by Porifera with 450 spp, Cnidaria Scleractinia 16 spp and Echinodermata 51 spp. Of these, 102 species are endemic to Brazilian reefs, including Porifera with 86 spp （18,44%）, Cnidaria Scleractinia 8 spp （50%）, and Echinodermata 8 spp （2.93%）. The results reflect the recent increase in taxonomic studies, and identify a large number of endemic species among the benthic invertebrate fauna of the Brazilian reefs.
文摘The marine area of Japan, including territorial waters and the exclusive economic zone, is the sixth largest in the world at about 4,470,000 km2. Therefore, it is becoming necessary to establish appropriate means of transportation other than ships in order to utilize the area efficiently. In this respect, ultra-light seaplanes are attracting attention from the viewpoint of protecting the natural environment. Accordingly, JRPS （Japan Reinforced Plastics Society） is currently developing FRP （fiber-reinforced plastic） floats for such planes. In this study, we conducted simulations of seaplane behavior during alighting by using the smoothed particle hydrodynamics method, which is one of the functions in the PAM-CRASH solver, and we present the observed trend in the vertical acceleration of the floats as a first step toward deriving the impact force from analytical data.
