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In the context of development and changes in two small-boat fisheries on the eastern Black Sea coast of Turkey, this article discusses how institutions are embedded in tradition, and what is “traditional” in “traditional knowledge”. Taking new institutional economics’ focus on institutions and approaches to traditional ecological knowledge as vantage points for discussion I compare systems of informal management in one discontinued and one new fishery to address questions such as: What kinds of knowledges and rules are involved in these kinds of fishing? What constitutes a tradition of knowledge? What is the role of tradition in working out new rules? I couple theories of situated knowledge (Ingold) and embeddedness of rules (Varela), both of which are inspired by Merleau-Ponty’s phenomenological approach, to show how institutions and traditional ecological knowledge are embedded and come together in practice.  相似文献   

3.
Vekhoff  Nicholas V. 《Hydrobiologia》1997,359(1-3):69-74
The Russian Territory known as the Barents Region includes the large islands of Vaigatch and Kolguev, the archipelagos of Franz Joseph Land and Novaya Zemlya, and many small near shore islands in the Barents Sea subregion of the Arctic Ocean. With the exception of Franz Joseph Land, these islands and the Novaya Zemlya Archipelago are inhabited by seven species of large branchiopods: four species of Anostraca, Polyartemia forcipata S. Fischer, 1851, Artemiopsis bungei plovmornini Jaschnov, 1925, Branchinecta paludosaMüller, 1851 and Branchinectella media (Schmankewitsch, 1873); one Notostraca, Lepidurusarcticus (Kroyer, 1847); and two species of Spinicaudata, Caenestheria propinqua Sars, 1901and C. sahlbergi (Simon, 1886). This is a richer large branchiopod fauna than occurs in other comparable land areas of the Arctic Ocean. The northern most known occurrence of Branchinecta paludosa is at Ivanov Bay on the Novaya Zemlya Archipelago. This report includes some life history observations. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

4.
The Irish Sea ia a relatively small, enclosed sea area which is subject to a wide range of human uses including navigation, oil terminals, dumping of sewage and industrial sludge, cooling for nuclear power stations, gravel extraction, gas and oil prospecting and fishing. Commercial fishing is affected by the other uses and at the same time it provides a means of monitoring their effects on a part of the ecosystem. Regular samples taken from fish markets provide a long series of age-composition data of the main commercial species — cod, whiting, plaice and sole — from which population changes can be assessed. More recently groundfish trawl surveys have been carried out to provide more detailed information on the distribution of all demersal fish species seasonally and in relation to area, depth and sediment type. Advice on the management of commercial fish species is prepared by a working group of the International Council for the Exploration of the Sea (ICES), and is based mainly on analytical single-species models. There are obvious shortcomings of such models in an area of mixed fishery and high diversity such as the Irish Sea. The objectives adopted in these models and in fisheries management generally are examined critically in relation to the possible aims of conservation.  相似文献   

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Among the edible species, jellyfish Rhopilema esculentum, is one of the most abundant and important fishery species in China. The jellyfish fishery is characterized by considerable fluctuations in catch and a very short fishing season. In this article, we first review the research results on the biology of R. esculentum, which previously were published in Chinese, as related to the jellyfish enhancement and fishery. Next, we review results from enhancement experiments conducted from 1984 to 2004, with the aims of stabilizing and increasing catch. During 2005 and 2006, stock enhancement of R. esculentum was carried out on a large scale for the first time in Liaodong Bay, China, where 414 million juvenile jellyfish (umbrella diameter > 1 cm) were released. We present results of these enhancements, including the survey methods, catch prediction, enhancement assessment, and fishery management. In 2005 and 2006, the recapture rate of released jellyfish was 3.0 and 3.2%, respectively. The fishermen earned ¥ 159 million during the 2 years. The ratio of the input (cost of culturing juvenile jellyfish) to the output (value of the sales) was about 1:18. The high commercial value of R. esculentum enhancement in Liaodong Bay makes this a very successful enterprise. Guest editors: K. A. Pitt & J. E. Purcell Jellyfish Blooms: Causes, Consequences, and Recent Advances  相似文献   

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The biomass and productivity of sea ice algae was assessed in the northwestern Barents Sea in May 2004. Sea ice algal pigment content was patchy with a mean of 18.5 ± 8.9 mg Chla m−2. The algal community was dominated by the diatom Nitzschia frigida. Primary production measured by 14C incubations was between 0.37 and 2.8 mg C m−2 h−1, which compared well with oxygen-based methods using the diffusive boundary layer approach (0.071–1.1 mg C m−2 h−1). Given the differences in the irradiances under which these two sets of measurements were made, there was a strong level of consistency between the two sets of results. Measurements of primary production were consistent with previous Arctic measurements but high spatial heterogeneity made a regional estimate of production inappropriate.  相似文献   

9.
The region between the Oka and Volga rivers has been largely neglected with respect to tardigrade biodiversity. In the present study a total of 21 species from 7 genera, 3 families, 2 orders and only 1 class of tardigrades were present, and some of their ecological preferences were noted. The tardigrades in the studied region were mainly cosmopolitan. Eurytopic, hygrophilic and xerophilic species were common while obligate freshwater species were not found. There is a marked similarity in the tardigrade fauna within similar habitats from different locations within the region.  相似文献   

10.
This article uses two case studies to assess the role of research in policy formation and fishery management. One study focuses on measures to limit the mortality of dolphins taken when tuna are harvested in the eastern tropical Pacific. The other studies measures taken to limit harvests of Southern Bluefin Tuna. Both of these fisheries involve fugitive resources and transboundary resources spreading across both national exclusive economic zones and the high seas. Both fisheries were initially based on open access, but public policy has led to greater exclusive use through individual transferable quotas for Southern Bluefin Tuna and dolphin mortality limits. A number of policy conclusions are drawn.  相似文献   

11.
In contemporary Aotearoa/New Zealand, Maori indigenous claims to fisheries have resulted in an uneasy compromise in which private property in fisheries coexists with an important element of common ownership. Individual Transferable Quotas and the bundle of rights encoded in Customary Fisheries Regulations are the expression of this compromise. At the legal level, these reflect the major property paradigms of private and communal. In practice, neither has accommodated Maori concrete relations of owning, and social practices of exchanging, fish.  相似文献   

12.
The past stormy fisheries relations between Canada and the European Union, in particular with Spain, has been replaced by uncertainty in the application of the newly amended Northwest Atlantic Fisheries Convention. These issues are addressed in this article that sheds light on the more peaceful fishing relations between the two leading international actors in this area of the oceans.  相似文献   

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The ultrastructure of male and female gametes of asconoid sponge Leucosolenia complicata(Calcispongiae, Calcaronea), a hermaphrodite species that reproduces in autumn, is described. The mature sponge's oocytes were up to 70 m in diameter, had no coatings, and contained a nucleus about 31 m in diameter with large nucleoli (up to 6.6 m). There were vacuoles with fibrillar contents typical of calcareous sponges in ooplasm. During vitellogenesis, a cluster of a great number of nurse cells developed above each oocyte from transformed choanocytes. Mature spermia of L. complicatalooked like orbicular cells about 2.5 m in diameter, with no acrosome or tail. The spermium nucleus (diameter about 2.2 m) was formed by incompletely condensed chromatin and was surrounded with a thin layer of cytoplasm of nonuniform thickness. In the thick layer of cytoplasm beyond the ribosomes, there were two or three mitochondria, dictyosomes, and electron-dense protein bodies lying freely under the nucleus. Fertilization occurred with the aid of a carrier cell. During spawning (mass release of spermia), any nurse cell complex can seize a spermium and transform into a carrier cell in situ. The transformation of a seized spermium into a spermiocyst was connected with the rapid isolation of the spermium nucleus from the protein body. Fertilization began with the penetration of the protein body into the oocyte cytoplasm. Only after this did the spermium's nucleus penetrate into the oocyte.  相似文献   

15.
During a visit to Norway by the Russian president in the spring of 2010, the president and the Norwegian prime minister surprisingly announced agreement on a delimitation line in the Barents Sea ending almost 40 years of negotiations. The agreement was signed in Murmansk on 15 September 2010. This article presents the background of the dispute and undertakes an assessment of the agreement and its implications for the Barents Sea, Svalbard, and other Arctic maritime delimitations.  相似文献   

16.
Dvoretsky VG. and Dvoretsky AG. 2011. Morphometric differentiation of Pseudocalanus minutus populations in the Barents Sea. —Acta Zoologica (Stockholm) 00 : 1–12. We investigated spatial variations in the morphometric characteristics (total length of body, lengths of cephalothorax, abdomen and antennules, and their relative proportions) of Pseudocalanus minutus, an abundant copepod species across the Barents Sea in August–September 2007. Females were found to have higher values for the measured parameters than males. The average absolute morphometric characters of both sexes increased from the south to the north. In most cases, parameters were similar in the southern, central, and eastern regions delineated by cluster analyses of oceanographic variables. The morphometric characteristics were strongly correlated with environmental variables in both males and females. Multiple regression analysis showed that temperature together with salinity explained 72–85% (in females) and 38–91% (in males) of the total variations in the log10‐transformed morphometric parameters. According to principal component analysis and discriminant function analysis, two distinct groups could be separated in the Barents Sea. The first group included the copepods from the northern region; the other included populations from the southern, central, and eastern regions. The observed morphological variation can be interpreted as geographical variation connected with hydrological variability.  相似文献   

17.
This paper presents data on 48 individuals of the rare high-boreal crab speciesGeryon tridens Krøyer, 1837, retrieved from the stomachs of cod caught in the southwestern part of the Barents Sea and adjacent waters in 1987–1997. There was only one large male with a carapace width of 58 mm; the other individuals were juveniles with carapace widths of 21–48 mm and masses of 3.2–27.5 g. The length: width ratio of the crab carapaceL=(0.85±0.06)H and the dependence of mass on carapace width (cm)W=0.4637H 2.73 atr=0.99 were calculated. Analysis of the data provides evidence that this crab species is expanding its range to the northeast and is sustaining its invasion of the Barents Sea, where it was first recorded no less than 10–15 years. It is concluded that this species now permanently inhabits the region of the Finmarken and Rybach'ya banks, forming rather dense aggregations there, and, on sites of cod catches, it predominantly inhabits depths of 180–320 m, where the warm Atlantic waters dominate and sand-silt bottoms prevail. These bottoms are favorable for the sheltering of crabs, which have a burrowing mode of life.  相似文献   

18.
Mathematical modelling was used to explore the seasonal and annual variability of primary, new and secondary production as well as sedimentation between 72° and 80°N in the central Barents Sea during the years 1981 to 1983. 1981 and 1982 were years with extensive ice coverage while 1983 experienced little sea-ice. The phytoplankton spring bloom started usually in April/May at about 75°N and was delayed from May/June in the south to August/September in the north as a function of thermal stratification and sea-ice dynamics. The model indicates that several, simultaneous spring bloom events, separated in space, can be found, especially during years with low ice coverage. The annual estimates of primary production, secondary production and sedimentation decreased on average from 73, 7.3 and 48 to 18, 1.8 and 9 g C m–2 year–1 between the southern and the northern part of the Barents Sea respectively. The annual estimates of particulate carbon flux were much higher in 1983 compared to 1981–1982, especially in the north where up to 6 times higher rates were calculated for 1983. The number of zooplankton species present in spring in the southern Barents Sea is governed by over-wintering success, but probably also influenced by advection of Atlantic water. The model was run for Atlantic water with 10,000, 3,000 or none copepods per m2 present in March, indicating that sedimentation can vary between 38 and 61 g C m–2 year–1 due to zooplankton grazing alone. This suggests that the supply of organic carbon to the aphotic zone of the Barents Sea is only partly determined by the strength and duration of phytoplankton blooms, but strongly influenced by zooplankton dynamics.  相似文献   

19.
The species composition and brief characteristic of some elements of structure of the ichthyofauna of the Barents Sea within its geographic boundaries are represented. During the whole historic period of observations in the Barents Sea, 182 species and subspecies of fish were recorded, belonging to 59 families, 28 orders, and 5 classes. Most species and subspecies belong to the boreal complex (59.3%), occur principally in the bottom layers (56.6%), more than a half feed on bottom and demersal invertebrates (52.2%), and are commercial species (52.7%). In the Barents Sea, 21 species and subspecies are commercial. Their ration in catches depends on the integral impact of natural and anthropogenous factors. In the arctic zone of the Barents Sea, the part of noncommercial species makes by biomass 1.18%; in the boreal zone—0.26%; in the Pechora Sea—10.6%.  相似文献   

20.
Diet composition of polar bears in Svalbard and the western Barents Sea   总被引:4,自引:2,他引:4  
We estimated both the numerical and biomass composition of the prey of polar bears (Ursus maritimus) from 135 opportunistic observations of kills in Svalbard and the western Barents Sea collected from March to October 1984-2001. By number, the prey composition was dominated by ringed seals (Phoca hispida) (63%), followed by bearded seals (Erignathus barbatus) (13%), harp seals (P. groenlandica) (8%) and unknown species (16%). However, when known prey were converted to biomass, the composition was dominated by bearded seals (55%), followed by ringed seals (30%) and harp seals (15%). Results indicated that bearded seals are an important dietary item for polar bears in the western Barents Sea. We believe that different patterns of space use by different bears may result in geographic variation of diet within the same population.  相似文献   

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