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961.
Insights from experimental economics on local cooperation in a small-scale fishery management system
Shankar Aswani Georgina G. Gurney Sara Mulville Jaime Matera Michael Gurven 《Global Environmental Change》2013,23(6):1402-1409
Cooperation is central to collective management of small-scale fisheries management, including marine protected areas. Thus an understanding of the factors influencing stakeholders’ propensity to cooperate to achieve shared benefits is essential to accomplishing successful collective fisheries management. In this paper we study stakeholders’ cooperative behavioral disposition and elucidate the role of various socio-economic factors in influencing it in the Roviana Lagoon, Western Solomon Islands. We employed a Public Goods Game from experimental economics tailored to mimic the problem of common pool fisheries management to elucidate peoples’ cooperative behavior. Using Ostrom's framework for analyzing social-ecological systems to guide our analysis, we examined how individual-scale variables (e.g., age, education, family size, ethnicity, occupational status, personal norms), in the context of village-scale variables (e.g., village, governance institutions, group coercive action), influence cooperative behavior, as indexed by game contribution. Ostrom's framework provides an effective window for conceptually peeling back the various socio-economic and governance layers which influence cooperation within these communities. The results of our research show that the most important resource user characteristics influencing cooperative behavior were age, occupation and beliefs about giving access to others to fish for commercial gain. Through elucidating the factors affecting stakeholders’ propensity to cooperate to achieve shared benefits, our analysis provides guidance in understanding cooperation in relation to collective management of marine resources. 相似文献
962.
STEFANO ANDREUCCI MARK D. BATEMAN CLAUDIO ZUCCA SELIM KAPUR İHSAN AKŞIT ADAM DUNAJKO VINCENZO PASCUCCI 《Sedimentology》2012,59(3):917-938
A multi‐disciplinary approach was followed to investigate two thick palaeosol strata that alternate with wind‐blown dominated deposits developed along the Alghero coast (North‐west Sardinia, Italy). Optically stimulated luminescence ages reveal that both palaeosols were developed during cooler drier periods: the first one at around 70 ka Marine Isotope Stage 4 and the latter around 50 ka (Marine Isotope Stage 3). In contrast, the pedological features indicate that the palaeosols underwent heavy weathering processes under warm humid to sub‐humid conditions, characteristic of the Sardinian climate during the last interglacial stage (Marine Isotope Stage 5e). To reconcile this apparent data discrepancy, a range of sedimentological and pedological analyses were conducted. These analyses reveal that the palaeosols possess a complex history, with accumulation and weathering occurring during Marine Isotope Stage 5e, and erosion, colluviation and final deposition taking place during the following cold stages. Thus, even if these reddish palaeosols were last formed during the glacial period, the sediments building up these strata probably record the climate of the last interglacial stage (Marine Isotope Stage 5e). Trace element and X‐ray diffraction analyses, together with scanning electron microscope images, reveal the presence of Saharan dust in the parent material of the palaeosols. However, no evidence of any far‐travelled African dust has been observed in the Marine Isotope Stage 4–3 aeolian deposits. It is possible to conclude that in the West Mediterranean islands, Saharan dust input, even if of modest magnitude, is preserved preferentially in soils accumulated and weathered during interglacial stages. 相似文献
963.
Troy A. Dexter Darrell S. Kaufman Richard A. Krause Jr. Susan L. Barbour Wood Marcello G. Simões John Warren Huntley Yurena Yanes Christopher S. Romanek Michał Kowalewski 《Quaternary Research》2014
To evaluate the potential of using surficial shell accumulations for paleoenvironmental studies, an extensive time series of individually dated specimens of the marine infaunal bivalve mollusk Semele casali was assembled using amino acid racemization (AAR) ratios (n = 270) calibrated against radiocarbon ages (n = 32). The shells were collected from surface sediments at multiple sites across a sediment-starved shelf in the shallow sub-tropical São Paulo Bight (São Paulo State, Brazil). The resulting 14C-calibrated AAR time series, one of the largest AAR datasets compiled to date, ranges from modern to 10,307 cal yr BP, is right skewed, and represents a remarkably complete time series: the completeness of the Holocene record is 66% at 250-yr binning resolution and 81% at 500-yr binning resolution. Extensive time-averaging is observed for all sites across the sampled bathymetric range indicating long water depth-invariant survival of carbonate shells at the sediment surface with low net sedimentation rates. Benthic organisms collected from active depositional surfaces can provide multi-millennial time series of biomineral records and serve as a source of geochemical proxy data for reconstructing environmental and climatic trends throughout the Holocene at centennial resolution. Surface sediments can contain time-rich shell accumulations that record the entire Holocene, not just the present. 相似文献
964.
Hendrik Lantzsch Till J.J. Hanebuth Cristiano M. Chiessi Tilmann Schwenk Roberto A. Violante 《Quaternary Research》2014
The continental margin off the La Plata Estuary (SE South America) is characterized by high fluvial sediment supply and strong ocean currents. High-resolution sediment-acoustic data combined with sedimentary facies analysis, AMS-14C ages, and neodymium isotopic data allowed us to reconstruct late Quaternary sedimentary dynamics in relation to the two major sediment sources, the La Plata Estuary and the Argentine margin. Sediments from these two provinces show completely different dispersal patterns. We show that the northward-trending La Plata paleo-valley was the sole transit path for the huge volumes of fluvial material during lower sea levels. In contrast, material from the Argentine margin sector was transported northwards by the strong current system. Despite the large sediment volumes supplied by both sources, wide parts of the shelf were characterized by either persistent non-deposition or local short-term depocenter formation. The location and formation history of these depocenters were primarily controlled by the interplay of sea level with current strength and local morphology. The high sediment supply was of secondary importance to the stratigraphic construction, though locally resulting in high sedimentation rates. Thus, the shelf system off the La Plata Estuary can be considered as a hydrodynamic-controlled end-member. 相似文献
965.
正1 Introduction Currently,all six different continents have discovered potash deposits and potash-bearing salt lake saline water.However,the distribution is extremely uneven,which is mostly concentrated in Canada,Russia,Middle-Asia and 相似文献
966.
LIU Chenglin WANG Licheng ZHAO Yanjun CAO Yangtong JIAO Pengcheng SHEN Lijian ZHANG Hua 《《地质学报》英文版》2014,88(Z1):225-226
正Chinese geologists have always been expecting to find out a large scale of potash deposits in marine basins,but only one small-middle scale industrial solid potash deposit had been found at Mengyejing in Langping-Simao basin 相似文献
967.
Atmospheric Deposition (AD) provides external nutrients such as nitrogen (N), phosphorus (P) and iron (Fe) supporting the growth of phytoplankton in oceans and thereby exerts obvious impacts on carbon and nitrogen cycles and climate change associated. Specifically, the external nutrients derived from atmospheric deposition can promote the marine primary production and nitrogen fixation that enhance the ocean capacity in absorbing CO2; AD may also change a few pathways of carbon and nitrogen cycles in oceans and increase the emissions of biogenic aerosol and radioactive gases such as N2O, DMS, etc. Due to the underlying important impacts on climate and environmental change, AD and processes related have become the hot topics of multidisciplinary studies in the areas of ocean and atmospheric sciences, and the focus of some international core projects such as Surface Ocean Lower Atmosphere Study (SOLAS), an International Study of Marine Biogeochemical Cycles of Trace Elements and Their Isotopes (GEOTRACES) and Integrated Marine Biogeochemistry and Ecosystem Research (IMBER). With the severe air pollution and high frequencies of Asian dust events, as the downwind areas of big cities and dust sources, the East China Sea and adjacent North Pacific have received increasing influences of AD. Limited studies showed that the increase of AD indeed caused significant influence on carbon and nitrogen cycles in these immediately related oceanic areas and the study there would have a signature effect on global oceans. A multidisciplinary study on the impacts of AD in oceans, e.g., combing molecular biology and experimental ecology techniques to study primary production processes, utilizing isotopic techniques to trace the change of the nitrogen cycle, new evidences of ocean-biogenic aerosol emissions, etc. would be the focus in the future. 相似文献
968.
Marine gas hydrate and cold-seep systems, which maintain a large amount of methane in the seabed, may critically impact the geochemical and ecological characteristics of the deep-sea sedimentary environment. However, it remains unclear whether marine sediments associated with gas hydrate harbor novel microbial communities that are distinct from those from typical marine sediments. In this study, microbial community structures thriving in sediments associated with and without gas hydrate in the eastern Japan Sea were characterized by 16S rRNA gene-based phylogenetic analyses. Uncultivated bacterial lineages of candidate division JS1 and a novel group NT-B2 were dominant in the sediments from gas hydrate-associated sites. Whereas, microbial populations from sites not associated with gas hydrate were mainly composed of Bacteroidetes, Nitrospirales, Chlamydiales, Chlorobiales, and yet-uncultured bacterial lineages of OD1 and TM06. The good correlation between the dominance of JS1 and NT-B2 and the association of gas hydrate could be attributed to the supply of more energetically favorable energy sources in gas-rich fluids from the deep subsurface than refractory organic matter of terrigenous and diatomaceous origin. 相似文献
969.
The history of glacial advances and retreats of the East Antarctic ice sheet during the Holocene is not well-known, due to limited field evidence in both the marine and terrestrial realm. A 257-cm-long sediment core was recovered from a marine inlet in the Rauer Group, East Antarctica, 1.8 km in front of the present ice-sheet margin. Radiocarbon dating and lithological characteristics reveal that the core comprises a complete marine record since 4500 yr. A significant ice-sheet expansion beyond present ice margins therefore did not occur during this period. 相似文献
970.
A literature review on trace metals and organic compounds of anthropogenic origin in the Wider Caribbean Region 总被引:2,自引:2,他引:0
About 30 studies from the published literature were reviewed to determine the pollution status regarding heavy metals and organic compounds of the Wider Caribbean Region (WCR). The literature revealed that most studies were performed in the South and Central American Caribbean Region with sparse reports on the small island states. Collectively, the most frequently analyzed heavy metals were Pb, Cu, Zn, Fe, Cd, Ni, Mn and Cr while DDT and its metabolites were the most frequently reported organic pollutants. The samples which were analyzed vary in terms of sampling schemes, parameters and analytical techniques, as well as differences in data reporting presentation (i.e. dry weight versus wet weight, sediment fraction analyzed, or % lipids). These differences make meaningful comparisons of the available data very difficult. Furthermore, there is limited data available for most of these contaminants from the majority of nations in the WCR. Therefore, any attempt to create a regional scale assessment from contaminants data available in the open literature is limited by the scarcity of available information. 相似文献