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101.
Global coral reef related tourism is one of the most significant examples of nature-based tourism from a single ecosystem. Coral reefs attract foreign and domestic visitors and generate revenues, including foreign exchange earnings, in over 100 countries and territories. Understanding the full value of coral reefs to tourism, and the spatial distribution of these values, provides an important incentive for sustainable reef management. In the current work, global data from multiple sources, including social media and crowd-sourced datasets, were used to estimate and map two distinct components of reef value. The first component is local “reef-adjacent” value, an overarching term used to capture a range of indirect benefits from coral reefs, including provision of sandy beaches, sheltered water, food, and attractive views. The second component is “on-reef” value, directly associated with in-water activities such diving and snorkelling. Tourism values were estimated as a proportion of the total visits and spending by coastal tourists within 30 km of reefs (excluding urban areas). Reef-adjacent values were set as a fixed proportion of 10% of this expenditure. On-reef values were based on the relative abundance of dive-shops and underwater photos in different countries and territories. Maps of value assigned to specific coral reef locations show considerable spatial variability across distances of just a few kilometres. Some 30% of the world's reefs are of value in the tourism sector, with a total value estimated at nearly US$36 billion, or over 9% of all coastal tourism value in the world's coral reef countries.  相似文献   
102.
In order to assess the diversity and spatial distribution of bacterial and archaeal communities in a CO2-rich and meromictic lake, samples were collected along the water column of Lake Monoun and analyzed using PCR-DGGE and quantitative analyses of the 16S rRNA gene. The retrieved sequences were affiliated to 6 bacterial phyla and two archaeal phyla which plausible environmental functions map with the physico-chemical parameters of the lake. Unclassified sequences were also detected. This suggests heterogeneity in community composition and existence of potential candidate divisions. For instance, amongst the bacterial sequences, 18.2% matched with methanotrophic bacteria of the order methylococcales and amongst the archaeal sequences, 16.6% matched with methanogenic species of the order methanomicrobiales. Hence, evidencing the existence of methane-related prokaryotes in the lake, a finding that would play a key role in our understanding of the methane puzzle of Lake Monoun. Other groups capable of a wide range of metal and nutrients transformations were also detected, as well as those of unknown functions. The layering of microbial communities also appeared to directly or indirectly depend on oxygen availability. DGGE and qPCR analyses both suggested a scarcity of archaea in the surface samples. Furthermore, qPCR revealed that bacteria were numerically more important than archaea in all the samples. The general distribution along the water column indicated that archaeal abundance increases with depth.  相似文献   
103.
We conducted the first quantitative assessment of coral breakage along a gradient of diving activities in Hong Kong, the most densely populated city in southern China. A survey of six 1 × 25 m transects at seven sites revealed a total of 81 broken corals, among which 44% were branching, 44% plate-like and 12% massive. There were 3–19 broken colonies per site. At most study sites, the percentage of broken corals exceeded the recommended no-action threshold of 4%, suggesting that management intervention is justified. There was a significant positive correlation between the number of broken coral colonies and the number of divers visiting the site. The branching Acropora and the plate-like Montipora suffered from much higher frequency of damage than their relative abundance, raising the concern that the cumulative impact of such differential susceptibility to breakage may affect coral community composition.  相似文献   
104.
《Marine pollution bulletin》2014,78(1-2):181-189
The HELCOM Red List biotopes project proposed a Baltic Sea wide classification consisting of six levels: The HELCOM Underwater biotopes/habitats classification system (HELCOM HUB). We present a case study from the south-western Baltic Sea where we tested the applicability of this system. More than 500 sampling stations were analyzed regarding macrozoobenthic communities and their linkage to environmental parameters. Based on the analyses of biotic and abiotic data, 21 groups were assigned to 13 biotopes of the classification. For some biotopes varying states of communities were recognized. Even though not all abiotic parameters are considered directly in the hierarchy of the classification in general, all soft-bottom communities could be allocated to a corresponding biotope. The application of the HELCOM HUB for the south-western Baltic Sea is feasible, in regard to the implementation of the European Marine Strategy Framework Directive as well as the Baltic Sea Action Plan.  相似文献   
105.
Sixteen rock samples were collected from the continental shelf and slope between Napier and Cape Turnagain, southern Hawkes Bay, most coming from offshore anticlinal ridges. Nine of the samples have a foraminiferal fauna of Upper Miocene and Pliocene age. The remainder cannot be dated, but most are probably of similar age. The foraminiferal. faunas are considered to have lived at depths ranging down to at least 1600 m deeper than the depth from which they were collected. Thus, the post‐depositional history of the samples includes tectonic uplift of similar magnitude since Upper Tertiary times. Because most of the samples arc very fine grained, unlike Recent sediments from ridges, it is suggested that the present regime of folding is largely post‐Pliocene in age.  相似文献   
106.
This study analyzes six vegetation communities in relation to current climatic parameters and eight climate change scenarios along an elevation gradient extending from 2,710 m to 4,210m in the Trans-Mexican Volcanic Belt. The projected movements of 25 plant species with the current restricted or wide altitudinal distributions were also modeled. To relate climatic parameters to the species and communities, a Precipitation/Temperature(P/T)index was used both for the current and the different climate-change scenarios. The temperatures are expected to increase by 1.1°C to 1.7°C by 2020 and by2°C to 3°C by 2050. A decrease of 4% to 13% in the annual precipitation is expected for the 2020 horizon,and a reduction between 3% and 20% is expected for2050. The reductions in water availability were projected for all altitude levels and plant communities.The most marked reduction was under the HADLEYA2 scenario, in which the lower limit of the altitudinal range increased from 2,710 to 3,310 m(2050 horizon)with reductions in the P/T index between 36% and39% compared to the current climate. Most plant species tended to shift their distribution from 200 to300 m upward in the 2020 temporal horizon scenarios. The Pinus hartwegii, Alnus jorullensis and Pinus montezumae communities would have a shorter altitudinal range as they move upward and merge with the remaining species at the higher altitudinal range. For the 2050 temporal horizon,30% of the species, primarily those from the higher altitudinal range, would disappear because their P/Tindex values would be above the limit of plant survival(4,210 m).  相似文献   
107.
Conservation organizations often invest considerable resources in education and outreach activities in and around marine protected areas (MPAs). The expectation is that such efforts will change local knowledge, attitudes and ultimately behavior. This is one of the first studies to assess the efficacy of using education and outreach activities to improve community knowledge and attitudes about an MPA. Random sample surveys in 2005 and 2010 (n=1213) before and after education and outreach activities are compared. Program budgets for the same period give the investment levels. With an investment level averaging US$24 per capita/year, the result was an average increase of 33% in “yes” responses across 15 indicators of knowledge and attitudes towards marine conservation. The increase in knowledge and positive attitudes was associated with a large decrease in “not sure” responses, suggesting that community members with fewer initial preconceptions are the most effective target for education and outreach activities. This study demonstrates that investments in MPA education and outreach can generate increases in local knowledge and positive attitudes, and changing knowledge and attitudes is expected to contribute to the long-term compliance with MPA regulations.  相似文献   
108.
109.
Motivated by theoretical arguments about ethnicity and economics and by historical research on urban black communities in the United States, this paper investigates the resilience of the early twentieth-century Black Metropolis. The study tests hypotheses about changes during the Great Depression (1930–1940) in the advantages of various cities as locations of black communities’ ethnic economies, analyzing Census data on blacks’ representation in occupations reflecting the Black Metropolis’s professional, entrepreneurial, and cultural media pursuits. There is mixed support for the hypothesis that the nationally dominant urban centers of New York, Chicago, and Philadelphia had the most resilient Black Metropolises, a finding that casts doubt on claims that black communities in such key places enjoyed exceptionally favorable locational advantages. Yet, the results support the hypothesis that northern cities were, overall, more resilient locations than southern cities, particularly for black professionals and entrepreneurs, affirming the argument that the urban North’s Black Metropolises were vital economic opportunity centers for these black communities’ upper- and middle-classes.  相似文献   
110.
Macroalgal blooms of Hypnea musciformis and Ulvafasciata in coastal waters of Maui only occur in areas of substantial anthropogenic nutrient input, sources of which include wastewater effluent via injection wells, leaking cesspools and agricultural fertilizers. Algal δ15N signatures were used to map anthropogenic nitrogen through coastal surveys (island-wide and fine-scale) and algal deployments along nearshore and offshore gradients. Algal δ15N values of 9.8‰ and 2.0-3.5‰ in Waiehu and across the north-central coast, respectively, suggest that cesspool and agricultural nitrogen reached the respective adjacent coastlines. Effluent was detected in areas proximal to the Wastewater Reclamation Facilities (WWRF) operating Class V injection wells in Lahaina, Kihei and Kahului through elevated algal δ15N values (17.8-50.1‰). From 1997 to 2008, the three WWRFs injected an estimated total volume of 193 million cubic meters (51 billion gallons) of effluent with a nitrogen mass of 1.74 million kilograms (3.84 million pounds).  相似文献   
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