区域性海洋治理机制:现状、反思与重构

区域海洋治理作为海洋治理的重要层次,发展至今已经在不同方向上形成各式治理机制。四种最重要的区域性海洋治理机制——依托区域一体化组织、区域海项目、区域渔业机构、大海洋生态系统,在地理范围、使命、参与方、制度架构及合作协调机制等方面各具特色,在区域海洋治理中各自发挥了独特的作用。整体而言,当前区域海洋治理存在个体机制脆弱、机制之间合作不足、分部门管理缺乏协调、区域之间差距巨大的问题。海洋命运共同体理念为重构区域性海洋治理机制指引了方向:在加强个体机制的基础上,尝试运用非正式的合作与协调,以大海洋生态系统作为突破口进行不同治理机制的整合。中国可以以此作为参与区域海洋治理的参考路径。

南海渔业合作协定的模式选择

由于南海岛礁主权和划界争端悬而未决,周边国家之间的渔业纠纷此起彼伏。加之过度捕捞和欠缺养护措施,南海渔业资源日趋衰竭,甚至有些鱼种已经绝迹。屡见不鲜的渔业纠纷和不断衰退的渔业资源使得南海渔业合作已势在必行。渔业合作协定的模式选择是达成协定时的关键问题,鉴于南海的实际情况,划定临时渔业边界难以实现,白色区域协定模式和轻灰色区域协定模式均非最优选择,而灰色区域协定模式是周边国家短期内应努力争取达成的。但从长远来看,以生态系统方法为导向的区域合作模式才是南海渔业合作的最佳路径。

Characterization and differential expression of three GnRH forms during reproductive development in cultured turbot Schophthalmus maximus

Turbots( Schophthalmus maximus), one of the most important economic marine flatfish species, fail to undergo final spawning and spermiation naturally under artificial farming conditions. In vertebrates, reproduction is regulated by the brain-pituitary-gonadal axis(BPG-axis), and gonadotropin releasing hormone(GnRH) is one of its key components. Therefore, to better understand the physiology of reproduction in the turbot, three of the genes encoding GnRH subtypes— sbGnRH, c GnRH-II and sGnRH —were cloned and sequenced by isolating the cDNA sequences. The localizations and patterns of expression of their mRNAs were also evaluated during seasonal gonadal development. All three mRNAs were expressed abundantly in the brain; sbGnRH and sGnRH mRNAs were also detected in the gonads and pituitary gland, and sbGnRH expression was much higher than that of sGnRH, indicating the critical role of sbGnRH in regulating the BPG-axis. Moreover, the brain expression patterns of sbGnRH and sGnRH mRNAs showed an increased trend during gonadal development, peaking in mature stages. This indicated the direct regulation of gonadal development by the GnRH system. In addition, c GnRH-II mRNA expression showed no significant variations, suggesting that c GnRH-II is not critically involved in the control of reproduction. Further, the mRNA abundances of the three GnRH forms in the breeding season were significantly higher than those in immature and post-breeding stages in all analyzed brain areas. Therefore, we propose that sbGnRH is the most important hormone for the regulation of reproduction in turbot via the BPG-axis. These results will help in better understanding the reproductive endocrine mechanisms of turbots and lay the groundwork for additional studies aimed at comparing the reproductive physiology of wild individuals with those raised under artificial conditions.

Dynamics of the Currents in the Strait of Khuran in the Persian Gulf

The Strait of Khuran is among the most important marine habitats in the Persian Gulf. It is the location of the largest Avicennia Marina mangroves along the Persian Gulf shoreline and is a major nursery region for the fish and to breeding, wintering and migrant water birds. This paper presents dynamics of the currents in the Strait of Khuran using the current data collected by fixed current meters. The analysis of the data showed that the currents in the Strait of Khuran were highly dominated by tidal forcing with mixed semi diurnal behavior. The tidal currents were strong and reached to a maximum velocity of 123 cm/s in the spring tide. Tidal analysis showed that the tidal current constituents （M2, $2, N2, K1, O1） are dominant with M2 component as the major one. The tidal currents occurred basically along the strait. The results show a westward residual flow along the strait with an average of 5.6 cm/s during the study. The direction of the flow indicates that any pollution discharged into the industrial developing eastern part of the strait has the potential to affect the sensitive ecosystem in the western part.

文本、经验与构造:南海渔业资源合作养护与管理

考虑到生态系统的自然法则属性,以及国家与人类共同利益的和谐统一,周边国家不应一直固守传统国际法所依赖的以"国家为中心"的威斯特伐利亚体系。但囿于条约的模糊性,主体加入的选择性,调整对象的广泛性,实施机制的羸弱性,包括《联合国海洋法公约》在内的现有国际立法和区域合作文件并不能真实、充分回应南海海域所面临的渔业资源枯竭和生态环境恶化的风险。而现有渔业合作模式也并非为南海区域的最佳选择。基于大海洋生态系统的《南海渔业协定》,融合了中国的主导性,区域的特定性,主体的多边性以及协定的约束性,通过秉承"共商共建共享"的全球治理理念和务实开放的姿态来探索区域合作。

Mass extinction and Pangea integration during the Paleozoic-Mesozoic transition

The greatest Phanerozoic mass extinction happened at the end-Permian to earliest Triassic. About 95% species, 82% genera, and more than half families became extinct, constituting the sole macro-mass extinction in geological history. This event not only caused the great extinction but also destroyed the 200 Myr-long Paleozoic marine ecosystem, prompted its transition to Mesozoic ecosystem, and induced coal gap on land as well as reef gap and chert gap in ocean. The biotic crisis during the Paleozoic-Mesozoic transition was a long process of co-evolution between geospheres and biosphere. The event sequence at the Permian-Triassic boundary （PTB） reveals two-episodic pattern of rapidly deteriorating global changes and biotic mass ex- tinction and the intimate relationship between them. The severe global changes coupling multiple geospheres may have affect- ed the Pangea integration on the Earth＇s surface spheres, which include： the Pangea integration→enhanced mountain height and basin depth, changes of wind and ocean current systems; enhanced ocean basin depth→the greatest Phanerozoic regression at PTB, disappearance of epeiric seas and subsequent rapid transgression; the Pangea integration→thermal isolation effect of continental lithosphere and decrease of mid-ocean ridges→development of continental volcanism; two-episode volcanism causing LIPs of the Emeishan Basalt and the Siberian Trap （25%251 Ma）→global warming and mass extinction; continental aridification and replacement of monsoon system by latitudinal wind system→destruction of vegetation; enhanced weathering and CH4 emission→negative excursion of δ^13C; mantle plume→crust doming→regression; possible relation between the Illawarra magnetic reversal and the PTB extinction, and so on. Mantle plume produced the Late Permian LIPs and mantle convection may have caused the process of the Pangea integration. Subduction, delamination, and accumulation of the earth＇s cool lithospheric material at the ＂D＂ layer of CMB started mantle plume by heat compensation and disturbed the outer core ther- too-convection, and the latter in turn would generate the mid-Permian geomagnetic reversal. These core and mantle perturbations may have caused the Pangea integration and two successive LIPs in the Permian, and probably finally the mass extinction at the PTB.

Navigating the currents of seascape genomics： how spatial analyses can augment population genomic studies

Population genomic approaches are making rapid inroads in the study of non-model organisms, including marine taxa. To date, these marine studies have predominantly focused on rudimentary metrics describing the spatial and environmental context of their study region （e.g., geographical distance, average sea surface temperature, average salinity）. We contend that a more nuanced and considered approach to quantifying seascape dynamics and patterns can strengthen population genomic investigations and help identify spatial, temporal, and environmental factors associated with differing selective regimes or demographic histories. Nevertheless, approaches for quantifying marine landscapes are complicated. Characteristic features of the marine environment, including pelagic living in flowing water （experienced by most marine taxa at some point in their life cycle）, require a well-designed spatial-temporal sampling strategy and analysis. Many genetic summary statistics used to describe populations may be inappropriate for marine species with large population sizes, large species ranges, stochastic recruitment, and asymmetrical gene flow. Finally, statistical approaches for testing associations between seascapes and population genomic patterns are still maturing with no single approach able to capture all relevant considerations. None of these issues are completely unique to marine systems and therefore similar issues and solutions will be shared for many organisms regardless of habitat. Here, we outline goals and spatial approaches for land- scape genomics with an emphasis on marine systems and review the growing empirical literature on seascape genomics. We review established tools and approaches and highlight promising new strategies to overcome select issues including a strategy to spatially optimize sampling. Despite the many challenges, we argue that marine systems may be especially well suited for identifying candidate genomic regions under environmentally mediated selection and that seascape genomic approaches are especially useful for identifying robust locus-by-environment associations.