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941.
The impacts of tourism on coral reef conservation awareness and support in coastal communities in Belize 总被引:1,自引:0,他引:1
A. Diedrich 《Coral reefs (Online)》2007,26(4):985-996
Marine recreational tourism is one of a number of threats to the Belize Barrier Reef but, conversely, represents both a motivation
and source of resources for its conservation. The growth of tourism in Belize has resulted in the fact that many coastal communities
are in varying stages of a socio-economic shift from dependence on fishing to dependence on tourism. In a nation becoming
increasingly dependent on the health of its coral reef ecosystems for economic prosperity, a shift from extractive uses to
their preservation is both necessary and logical. Through examining local perception data in five coastal communities in Belize,
each attracting different levels of coral reef related tourism, this analysis is intended to explore the relationship between
tourism development and local coral reef conservation awareness and support. The results of the analysis show a positive correlation
between tourism development and coral reef conservation awareness and support in the study communities. The results also show
a positive correlation between tourism development and local perceptions of quality of life, a trend that is most likely the
source of the observed relationship between tourism and conservation. The study concludes that, because the observed relationship
may be dependent on continued benefits from tourism as opposed to a perceived crisis in coral reef health, Belize must pay
close attention to tourism impacts in the future. Failure to do this could result in a destructive feedback loop that would
contribute to the degradation of the reef and, ultimately, Belize’s diminished competitiveness in the ecotourism market.
相似文献
A. DiedrichEmail: |
942.
The Palauan archipelago contains one of the most ecologically diverse coral reef systems in the Indo-Pacific that was as attractive
for humans prehistorically as it is today. New evidence is emerging that during the past few thousand years there has been
increasing exploitation of coral reef resources, particularly finfish and mollusks, leading to a decline in taxa numbers,
richness, and diversity in various locales. This paper examines the historical interactions between human populations and
coral reef ecologies in Palau by combining known archaeological data and results from modern biological data of different
reef fauna. The integration of these data sources provides a framework for attempting to explain variations in taxa composition
between islands in the archipelago and how this may relate to human exploitation or other phenomena through time. By using
this perspective to link past events with present-day conditions, we can gain a better sense of the extent to which anthropogenic
changes may have affected island environments in western Micronesia during the Late Holocene. The study also illustrates the
many difficulties researchers face in attempting to synthesize and explain past and present human predation behavior when
using disparate sources of data.
相似文献
S. M. FitzpatrickEmail: |
943.
The determination of phenotypic and genotypic traits of a group of closely related Vibrio strains from the Baltic Sea did not allow species designation. DNA-DNA hybridization and fatty acid analysis revealed them as Vibrio navarrensis. Therefore we suggest these Vibrios to represent a new biotype, named V. navarrensis biotype pommerensis. 相似文献
944.
Patrick T. Moss A. Peter Kershaw 《Palaeogeography, Palaeoclimatology, Palaeoecology》2007,251(1):4-22
A late Quaternary marine palynological record from the Ocean Drilling Program (ODP) site 820, adjacent to the humid tropics region of northeastern Australia, has demonstrated marked variation in orbital scale cyclicity, and also trends associated with both climate and human impact. However, some uncertainties in interpretation have resulted from concerns about the records chronology and continuity. Here we present, for the first time, the complete palynological data from detailed analysis of the top 67 m of sediment and examine it in relation to the marine isotope sequence from the core. It is proposed that the record is relatively continuous through the last 250,000 years although the latter part of oxygen isotope stage (OIS) 5, as well OIS 4 may be missing. Despite the variation on orbital scales, most palynological changes are not in phase with those from the marine isotope record suggesting a lack of direct Milankovitch forcing on vegetation. This lack of correspondence combined with major trends towards more open and sclerophyllous vegetation in association with increased burning supports a previous proposal that major control is being exercised by El Niño-Southern Oscillation variability whose influence may have been initiated by changes in oceanic circulation in the region within the mid Pleistocene. The lack of impact on the distribution of complex rainforest suggests that increased climate variability did not involve an overall decrease in total precipitation. 相似文献
945.
Tan LT 《Phytochemistry》2007,68(7):954-979
The prokaryotic marine cyanobacteria continue to be an important source of structurally bioactive secondary metabolites. A majority of these molecules are nitrogen-containing compounds biosynthesized by large multimodular nonribosomal polypeptide (NRP) or mixed polyketide-NRP enzymatic systems. A total of 128 marine cyanobacterial alkaloids, published in the literature between January 2001 and December 2006, are presented in this review with emphasis on their biosynthesis and biological activities. In addition, a number of highly cytotoxic compounds such as hectochlorin, lyngbyabellins, apratoxins, and aurilides have been identified as potential lead compounds for the development of anticancer agents. A brief coverage on the distribution of natural product biosynthetic genes as well as the mechanisms of tailoring enzymes involved in the biosynthesis of cyanobacterial compounds will also be given. 相似文献
946.
A Gram-negative, strictly aerobic, coccoid to short rod-shaped marine bacterium strain MKT107(T) was isolated from the molluscan top shell Omphalius pfeifferi pfeifferi collected on the coast of Japan. Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain MKT107(T) constitutes a new lineage in alpha-Proteobacteria related to the genera Nereida, Roseobacter, Staleya, Oceanibulbus and Sulfitobacter. Strain MKT107(T) was found to require salt for its growth and to be mesophilic. It contained 18:1omega7c and 16:0 as major cellular fatty acids and 3-OH 10:0 and 3-OH 12:0 as hydroxy fatty acids. The DNA base composition of the isolate was 61.6 mol% G+C. The major quinone was Q-10. Sufficient differences existed to distinguish this strain from currently recognized bacterial genera. Therefore, the isolate is classified as representing a new genus and species, Tateyamaria omphalii gen. nov., sp. nov. (type strain MKT107(T) =IAM 15108(T) =KCTC 12333(T); GenBank accession no. AB193438). 相似文献
947.
Coral reef ecosystems depend on the balanced interplay of constructive and destructive processes and are increasingly threatened by environmental change. In this context bioeroding sponges play a significant role in carbonate cycling and sediment production. They occasionally aggravate erosional processes on disturbed reefs. Like other coral ecosystems, Indian reefs have suffered from local and global effects. However, the systematic affiliation and diversity of many Indian bioeroding sponges and their infestation rates are largely confused or unknown. The present study describes a new bioeroding sponge species, Cliona thomasi sp. nov. from the central west coast of India. It belongs to the Cliona viridis species complex, displaying the key characters of tylostyles and spirasters, as well as harbouring photosymbiotic dinoflagellates. Specific morphological characteristics and molecular data from nrITS1 DNA and 28S rDNA distinguished C. thomasi sp. nov. from other known C. viridis complex and a number of Spheciospongia species. The historic sample of ‘Suberites coronarius’ from Mergui Archipelago (sensu Carter, 1887), but not from the Caribbean (sensu Carter, 1882), is conspecific with C. thomasi sp. nov. Cliona thomasi sp. nov. is locally very abundant, appears to be a key bioeroder, and thus regular monitoring of its abundance, distribution and infestation patterns is recommended. 相似文献
948.
Temperature and zooplankton size structure: climate control and basin‐scale comparison in the North Pacific
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Sanae Chiba Sonia D. Batten Tomoko Yoshiki Yuka Sasaki Kosei Sasaoka Hiroya Sugisaki Tadafumi Ichikawa 《Ecology and evolution》2015,5(4):968-978
The global distribution of zooplankton community structure is known to follow latitudinal temperature gradients: larger species in cooler, higher latitudinal regions. However, interspecific relationships between temperature and size in zooplankton communities have not been fully examined in terms of temporal variation. To re‐examine the relationship on a temporal scale and the effects of climate control thereon, we investigated the variation in copepod size structure in the eastern and western subarctic North Pacific in 2000–2011. This report presents the first basin‐scale comparison of zooplankton community changes in the North Pacific based on a fully standardized data set obtained from the Continuous Plankton Recorder (CPR) survey. We found an increase in copepod community size (CCS) after 2006–2007 in the both regions because of the increased dominance of large cold‐water species. Sea surface temperature varied in an east–west dipole manner, showing the typical Pacific Decadal Oscillation pattern: cooling in the east and warming in the west after 2006–2007. The observed positive correlation between CCS and sea surface temperature in the western North Pacific was inconsistent with the conventional interspecific temperature–size relationship. We explained this discrepancy by the geographical shift of the upper boundary of the thermal niche, the 9°C isotherm, of large cold‐water species. In the eastern North Pacific, the boundary stretched northeast, to cover a large part of the sampling area after 2006–2007. In contrast, in the western North Pacific, the isotherm location hardly changed and the sampling area remained within its thermal niche throughout the study period, despite the warming that occurred. Our study suggests that while a climate‐induced basin‐scale cool–warm cycle can alter copepod community size and might subsequently impact the functions of the marine ecosystem in the North Pacific, the interspecific temperature–size relationship is not invariant and that understanding region‐specific processes linking climate and ecosystem is indispensable. 相似文献
949.
大型海藻浒苔热解特性与动力学研究 总被引:2,自引:0,他引:2
以2005年10月采自江苏如东海区的条浒苔(Enteromorpha clathrata)为研究材料,用热重分析法对其热解过程及其动力学规律进行了研究。采用10、20、30℃/min等升温速率分别对0.18、0.28、0.45mm等粒径样品进行热解,结果表明样品非等温失重过程主要为脱水、保持、剧烈失重和缓慢失重4个阶段,且热解失重区为190~520℃之间范围;通过对最大失重率Dmax、失重率峰值温度θmax、挥发等参数分析,可以得出温度Ts和r值都随升温速率的增加而增加,升温速率越高,反应时间越短,热解特性指数增加;当样品粒径为0.28mm以上时,颗粒粒径越大对热解过程影响较大。用Coats-Redfern方法计算出样品的热解动力学参数,发现其热解反应机理函数不同于木质类生物质,求得的活化能E与频率因子A之间存在动力学补偿效应。 相似文献
950.
Lydie M. Dupont Hermann Behling Susanne Jahns Fabienne Marret Jung-Hyun Kim 《Vegetation History and Archaeobotany》2007,16(2-3):87-100
The distribution of pollen in marine sediments is used to record vegetation changes over the past 30,000 years on the adjacent
continent. A transect of marine pollen sequences from the mouth of the river Congo (∼5°S) to Walvis Bay and Lüderitz (∼25°S)
shows vegetation changes in Congo, Angola and Namibia from the last glacial period into the Holocene. The comparison of pollen
records from different latitudes provides information about the latitudinal shift of open forest and savannahs (Poaceae pollen),
the extension of lowland forest (rain forest pollen) and Afromontane forest (Podocarpus pollen), and the position of the desert fringe (pollen of Caryophyllaceae, Chenopodiaceae and Amaranthaceae). High Cyperaceae
pollen percentages in sediments from the last glacial period off the mouth of the river Congo suggest the presence of open
swamps rather than savannah vegetation in the Congo Basin. Pollen from Restionaceae in combination with Stoebe-type pollen (probably from Elytropappus) indicates a possible northwards extension of winter rain vegetation during the last glacial period. The record of Rhizophora (mangrove) pollen is linked to erosion of the continental shelf and sea-level rise. Pollen influx is highest off river mouths
(10–2000 grains year−1 cm−2), close to the coast (300–6000 grains year−1 cm−2), but is an order of magnitude lower at sites situated far from the continent (<10 grains year−1 cm−2). 相似文献