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1.
Guatemala's rich coastal and marine biodiversity provides essential ecosystem goods and services to local residents and the national economy through artisanal and commercial fisheries, aquaculture, port exports and, to a lesser extent, tourism. As in many other countries, national policies emphasise the significance of marine conservation and marine resources, primarily through implementing marine protected areas (MPAs). However, this assumes that governance, as reflected in legal, institutional and organizational frameworks, political capacity and human resources is sufficiently developed to ensure MPAs meet these goals. These issues are explored through presenting the first detailed analysis of coastal and marine governance in Guatemala. The research highlights a range of barriers to good governance which restrict the extent to which MPAs can function effectively. Recommendations are made which can capitalise upon the potential for locally managed marine areas as a means to facilitate the improved governance of coastal and marine resources in Guatemala.  相似文献   

2.
The grouping characteristics of sea waves in the Shijiu Port   总被引:1,自引:0,他引:1  
A review concerning the methods of studying and describing wave groups is presented in this paper. After analysing 78 field records collected in the Shijiu Port, China, the measured parameters of wave groups and some factors describing wave groupness and their variations are given. Moreover, these results are compared with those of theory.  相似文献   

3.
In this paper, the response of the atmospheric 3-5 year cycle to Northern Pacific SST is discussed, The results are as follows:1. From the simultaneous temporal correlations between the Equatorial Eastern Pacific SST, the westerly dirft area's SST and the Northern Pacific SST at all gridpoints, we find that there are three correlative regions in the Northern Pacific SST field, they are the westerly drift area, the Equatorial Eastern Pacific and the Alaska Bay , and their structures are very similar to the PNA pattern in the atmosphere The difference PTI between the Equatorial Eastern Pacific SST anomaly and the westerly drift area's SST anomaly can indicate the change of the PNA pattern of the Northern Pacific SST anomaly. It can represent SST change of 65 % areas over the Northern Pacific and can keep watch on El Nino and un-El Nino.2. Simultaneous temporal correlative field between PTI and filtered 500hPa (there is 3-5 year cycle only ) of the Northern Hemisphere presents clear PNA structure. The resp  相似文献   

4.
In this paper the seasonal variation and structural characteristics of the sea/ land breeze in the northern coastal area of" Shandong Peninsula are studied in two ways: one is the analysis of the observed wind data, and the other is numerical simulation and experiments. Firstly, the hour to hour wind data through the year 1984 at Longkou Meteorological Station and Yantai Oceanographic Station are analysed through energy spectra and hodograph. It is revealed from the analysed results that the effects of the sea/ land breeze in the area are notable in spring, summer and fall, especially in May. However, in winter the effects of sea / land breeze are not obvious. because the cold noitherly is prevailing. Secondly, a two-dimensional non- linear model of primitive equations is used to study the sea / land breeze circulation in May in the area. The results of numerical simulation consist basically with the analysed results of the observed sea / land breeze. A reasonable theoretical structure of the sea / land  相似文献   

5.
Having been calculated and analysed, it is found in this research paper that there exist a close lag relationship between sea surface temperature (SST) change in the north of the North Atlantic and height change at 500 hPa level in South Asia. In this paper, it is focused on the analysis of physical processes of the relation between SST and height and their effect on summer monsoon in South Asia.  相似文献   

6.
The European Commission has repeatedly requested its Member States to fully implement one of the world's oldest nature legislation laws, the Birds Directive, by designating Special Protection Areas (SPAs) in the marine environment. The current work analyses the spatial coverage offered by the SPA network to the 82 species of seabirds that occur in EU waters, and compare it to that of Important Bird and Biodiversity Areas (IBAs), as defined by BirdLife International. Marine SPAs represent 3.9% of the EU's marine area, while the IBA network represents 4.4%. On average, only 0.05% of the EU marine area is protected, and there are enormous regional differences. On average, SPAs and IBAs both cover 16.0% of the breeding distribution range of seabird species, but only1.4% of their non-breeding distribution range. SPAs cover more than 50% of the breeding range of only one seabird family, Procellariidae, and both SPA and IBA networks offer greater coverage to threatened species than to non-threatened ones. The year when Member States were legally obliged (2008 onwards) to declare their marine SPA networks is not significantly related to their network size, and that those species subjected to tracking studies or have well known breeding colonies benefit from higher coverage. Methodological challenges that were once posed to implement the Birds Directive at sea are largely overcome, and political will is the main driver for identifying, designating and managing a complete network of marine SPAs in the EU.  相似文献   

7.
Exposures of both living and dead biogenic rock built by calcarous algae, madreporaria and serpulids are present in the northern Adriatic Sea. These asymmetrical patch reefs, which project up to 4 m above the present sea floor, are best developed off Chioggia, Italy, in water depths ranging from 17 to 24 m. Side-scan sonar traverses showed that individual reef exposures are areally irregular and ranged in size from roughly 1 to 100,000 m2.  相似文献   

8.
Toxic cyanobacteria have been linked to dog deaths in the Waikanae River (1998) and Mataura River (1999 and 2000), New Zealand. These were Oscillatoria‐like species which formed benthic mats. This is the first time in New Zealand that animal deaths have been linked to toxins from benthic cyanobacteria.  相似文献   

9.
Using the air-sea data set of January, 1983 (the mature phase of the 1982/83 El Nino event), the net radiation on the sea surface, the fluxes of the latent and the sensible heat from ocean to the atmosphere and the net heat gain of the sea surface are calculated over the Indian and the Pacific Oceans for the domain of 35°N-35°S and 45°E-75°W. The results indicate that the upward transfer of the latent and the sensible heat fluxes over the winter hemisphere is larger than that over the summer hemisphere. The sensible heat over the tropical mid Pacific in the Southern Hemisphere is transported from the atmosphere to the ocean, though its magnitude is rather small. The latent heat flux gained by the air over the eastern Pacific is less than the mean value of the normal year. The net radiation, on which the cloud amount has considerable impact, is essentially zonally distributed. Moreover, the sea surface temperature (SST) has a very good correlation with the net radiation, the region of warm SST coinci  相似文献   

10.
Measurements of gas-, particle- and precipitation-phases of atmospheric mercury (Hg) were made in the South and equatorial Atlantic Ocean as part of the 1996 IOC Trace Metal Baseline Study (Montevideo, Uruguay to Barbados). Total gaseous mercury (TGM) ranged from 1.17 to 1.99 ng m−3, with a weighted mean of 1.61±0.09 ng m−3. These values compare well with Pacific Ocean data and earlier results from the Atlantic. The open-ocean samples recorded a distinctive inter-hemispheric gradient, which is consistent with a long-lived trace gas emitted to a greater extent from the Northern than from the Southern Hemisphere. Correlations with surface 222Rn measurements indicate an influence of regional terrestrial sources on open-ocean TGM concentrations. Total Hg in precipitation ranged from 10 to 99 pM (volume-weighted average: 17.8±2.9 pM). On average, about 72% of the total Hg was “reactive” (i.e., reducible by SnCl2). The data showed an apparent rapid nonlinear decrease in concentration with event size (“washout curve”). The wet depositional flux was estimated at 18–36 nmol m−2 yr−1 (4–7 μg m−2 yr−1), which is slightly lower than that found in mid-continental locations of North America (6–12 μg m−2 yr−1). 210Pb analyses indicate a strong impact of particles on rain Hg concentrations. Particle-phase Hg (range 5–25 fmol m−3; mean 12±1 fmol m−3; 66% “reactive”) was comparable to values over the equatorial Pacific. The dry depositional flux is ca. 0.4 nmol m−2 yr−1, or 0.4–1.0% of the wet flux. Particle-phase Hg concentrations did not change significantly when African dust was present during sampling. However, the Hg/Al ratios were consistent with crustal values during the dust periods. The residence time of TGM was calculated to be 1.3–3.4 yr in this region, based on standing stock estimates. Incubation of rainwater added to surface seawater gave reduction rates [i.e., production of elemental Hg (Hg°); 1.6–4.3% d of total Hg added] comparable to additions of inorganic ionic standards, indicating that Hg+2 from precipitation is reduced in a similar manner in surface waters. Thus, precipitation-phase Hg is generally available for evasion to the atmosphere following deposition to the surface ocean, effectively enhancing the mobility and residence time of Hg at the Earth's surface.  相似文献   

11.
-In this paper the variations of the sea surface temperature anomalies (SSTA) in the Equatorial Eastern Pacific are analysed. The results show that there are two peaks in the spectrum. One is the low frequency oscillation with a period of 3 - 5 years, and the other is the quasi-biennial oscillation. The former shows a westward migration in the warm episode of SSTA and the latter has the opposite trend. The El Nino events will be formed while the two frquency bands are in phase in the warming stage of SSTA in the Equatorial Eastern Pacific  相似文献   

12.
The “harmful algae and algal toxins in coastal waters of China:investigation and database”project (HAATC) is funded (US$2.3 million) by the Ministry of Science and Technology of China for 60months starting on the 1s t Jan 2019. Since the 1990s, national projects and other related work have greatly improved harmful algal bloom (HAB) research in China. However, the existing research on HABs is often limited to specifi c sea areas or specifi c algal bloom disasters, which is insu ffi cient for unde...  相似文献   

13.
14.
The article offers an analysis of the globalisation debate in the context of international fisheries governance. It argues that there are significant transformations in fisheries policy-making in international economics, international institutions and international law-making which alter state authority in fisheries management. Thus, decision-making at international, regional and national levels is increasing, displaced from the state level. This ‘multi-level’ decision-making is exemplified in the United Nations Food and Agricultural Organisation's Code of Conduct for Responsible Fisheries, 1995. The Code represents a sound instrument of fisheries governance, capable of responding to contemporary global transformations. Changes are illustrated by comparing the Code and the Agreement on Straddling Fish Stocks and Highly Migratory Fish Stocks, 1995, in the areas of international economics, institutions and law-making. Reference is made to interaction between a range of actors and to formal and informal procedures. In conclusion, a process of ‘fisheries governance’ is confirmed, emerging from a new environment of international fisheries relations.  相似文献   

15.
Izvestiya, Atmospheric and Oceanic Physics - By using a nonstationary numerical thermohydrodynamic model of atmospheric tides genesis and evolution in the Earth’s atmosphere, it is shown that...  相似文献   

16.
This paper examines the effects of neoliberalization on the opportunities and constraints that fishing cooperatives face in Yucatán, Mexico. Cooperatives have the potential to enhance small-scale fishing livelihoods and participate in sustainable resource governance. However, promoting cooperatives’ success entails developing a realistic understanding of the political and economic contexts in which they operate. Drawing on interview and census data, the analysis employs the theory of club goods to examine how the neoliberalization of Mexican fisheries policies in the 1980s and 1990s has affected cooperatives’ ability to provide members with collective benefits, and thus the success and failure of fishing cooperatives in the region. In general, neoliberalization has reduced support to fishing cooperatives and generated greater challenges for their success in Yucatán. The results of this study are likely relevant to many other small-scale fisheries in the South that have undergone similar processes of neoliberalization.  相似文献   

17.
The northern Gulf of Mexico and its diverse natural resources are threatened by population and development pressure, and by the impacts of rising sea level and severe storms. In the wake of the devastating 2005 hurricane season, and in response to the complex management issues facing the region, the U.S. Geological Survey organized the multidisciplinary “Northern Gulf of Mexico Ecosystem Change and Hazards Susceptibility” project. This special issue of Geo-Marine Letters hosts a few of the early results in the form of 11 papers covering three themes: (1) the control exerted by the underlying geologic framework on geomorphology and nearshore processes and features; (2) impact of human activities on nearshore water quality; and (3) hurricanes and associated effects.  相似文献   

18.
19.
《Oceanologica Acta》1999,22(5):499-515
Water column pCO2 and air-sea CO2 fluxes were studied during an 18-month period (May 1994–September 1995) in a coastal embayment affected by upwelling, located in the northwestern Iberian Peninsula (Ria de Vigo and adjacent shelf). Overall, the region acted as a net annual atmospheric CO2 sink, with magnitude ranging from 0.54 mgC m−2d−1 in the Ria estuary to 22 mgC m−2d−1 offshore. During moderate upwelling and upwelling relaxation conditions the sampling area was a sink for atmospheric CO2. By contrast, during winter conditions and during intense upwelling the flux reversed towards the atmosphere. The relative influence of physical and biological processes on pCO2 was evaluated using two different approaches: firstly, statistical analysis of physico-chemical correlations, and secondly, a thermodynamic analysis in the oceanic CO2 system. Both methods yielded consistent results, showing that the main processes controlling seasonal and spatial pCO2 variability were the production and remineralization of organic matter, explaining ca. 70 % of the total variability. In the inner part of the embayment, air-sea CO2 exchange was mainly modulated by CO2 partial pressure gradient, whereas in the adjacent shelf, wind speed largely contributed to CO2 fluxes between the ocean and the atmosphere.  相似文献   

20.
The evaporitic layer located at 35 km south of Toulon, according to compressional-wave velocity measured in samples from JOIDES-DSDP Leg 13 drillings in the Mediterranean Sea, could be constituted by gypsum or anhydrite, halite having been deposited in the most central parts of the basin. These deductions are in favour of the supposed “bull's eye” structure for evaporitic layers in the Mediterranean Sea.  相似文献   

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