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1.
The stalemate since 2012 over the establishment of marine protected areas (MPAs) in the Southern Ocean has been a source of debate within and outside the Commission for Conservation of Antarctic Marine Living Resources (CCAMLR). In 2015, China's support for the proposal for the establishment of a Ross Sea MPA was commended as a major step forward. As the newest Member of the CCAMLR, China refrained itself from commenting specifically on the issue of MPAs in the previous years, and had not articulated clearly its basic position until 2014. In light of its basic position and practices, China may become more active, maintain its basic position and take a case-by-case approach in relation to other MPA proposals. Moreover, bilateral interaction is helpful in finding practical solutions.  相似文献   

2.
The results from a time series study (1989–2005) at a depth of 4850 m on the Porcupine Abyssal Plain, NE Atlantic, are presented, showing radical changes in the density of large invertebrates (megafauna) over time. Major changes occurred in a number of different taxa between 1996 and 1999 and then again in 2002. One species of holothurian, Amperima rosea, was particularly important, increasing in density by over three orders of magnitude. There were no significant changes in total megafaunal biomass during the same period. Peaks in density were correlated to reductions in mean body size, indicating that the increases were related to large-scale recruitment events. The changes occurred over a wide area of the Porcupine Abyssal Plain. Comparisons made with changes in the density of protozoan and metazoan meiofauna, and with macrofauna, showed that major changes in community structure occurred in all size fractions of the benthic community at the same time. This suggests that the faunal changes were driven by environmental factors rather than being stochastic population imbalances of one or two species. Large-scale changes in the flux of organic matter to the abyssal seafloor have been noted in the time series, particularly in 2001, and may be related to the sudden mass occurrence of A. rosea the following year. Time-varying environmental factors are important in influencing the occurrence of megafauna on the abyssal seafloor.  相似文献   

3.
Historical and contemporary data on Benguela seabirds assumed to be responsive to changes in food availability are reviewed as potential indicators and predictors of change in the ecosystem. Cyclic variations in the annual yields of seabird products evident at decadal long time-scales may reflect fluctuations in prey populations at similar periods. However, no such relationship has been demonstrated and consequently the value of such annual yields as indicators is not proved. More recently, interannual variation in diets, foraging effort, breeding success and chick growth of two of the three most abundant species of seabird in the ecosystem have been examined in relation to changes in prey abundance. Although the relative abundance of important forage species in the diets of both species of seabird have reflected regional changes in the absolute abundance of these prey, changes in the values of other parameters thought to reflect food availability were not consistently correlated between and within species. This indicates poor potential for their use as indicators of change at least over the range of abundances experienced in this study. Under present management protocol, data from seabirds do not nor are likely to provide abundance indices that may be used directly in stock assessment of commercially important species. To date, insights into distribution and migration of pelagic fish provided by seabird-derived data probably represent the most valuable contribution of birds to fisheries scientists studying the Benguela system.  相似文献   

4.
Terrestrial crops for biofuel may make a negligible contribution to net greenhouse gas emissions [1], [2] and may cause other environmental impacts such as reducing freshwater resources and food security [3]. In light of these facts there is increasing interest in the production of marine biofuels [4], [5], and so the recent paper in Marine Policy by Roberts and Upham [6] reviewing the cultivation and harvest of UK and Irish seaweeds for biofuels is very pertinent and timely. However it contains a number of factual errors that need correcting and raises several issues, which need fuller clarification. These issues centre around three main themes: (1) a confusion between the occurrence and harvest of intertidal and subtidal species, (2) the relative suitability of seaweeds, and their source (wild harvest versus culture) as feedstock for biofuel generation and (3) an appreciation of the scale at which macroalgae would have to be produced to make any impact on biofuel targets.  相似文献   

5.
This article investigates the role and value of user participation in fisheries management. New empirical data on changes in the institutional structure of fisheries management systems is presented by examining the management structure of two Danish fisheries. The analysis focuses on how user participation functions are institutionalized as co-management between administrators and user groups. General lessons for successful user participation in management are deduced. The paper concludes that co-management is able to overcome some of the fundamental problems related to modern fisheries management and that co-management can work as an active and effective management tool rather than as an impediment to efficient management.  相似文献   

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