共查询到20条相似文献，搜索用时 593 毫秒
1.
Maria Vanessa Baria‐Rodriguez Dexter W. dela Cruz Romeo M. Dizon Helen T. Yap Ronald D. Villanueva 《水产资源保护:海洋与淡水生态系统》2019,29(6):891-900
- 相似文献
2.
- 1. Forest restoration through silviculture (gardening) programs revives productivity, biodiversity, and stability. As in silviculture approaches, the coral ‘gardening’ strategy is based on a two‐step protocol.
- 2. The first step deals with the establishment of in situ and/or ex situ coral nurseries in which corals are farmed (originating from two types of source material: asexual [ramets, nubbins], and sexual [planula larvae, spat] recruits).
- 3. The second is the reef rehabilitation step, where maricultured colonies are transplanted into degraded sites.
- 4. We compare here the rationale of forest restoration to coral reef ecosystem restoration by evaluating major key criteria. As in silviculture programs, a sustainable mariculture operation that focuses on the prime structural component of the reef (‘gardening’ with corals) may promote the persistence of threatened coral populations, as well as that of other reef taxa, thus maintaining genetic diversity. In chronically degrading reef sites this may facilitate a halt in biodiversity depletion.
- 5. Within the current theoretical framework of ecosystem restoration, the recovery of biodiversity indices is considered a core element since a rich species diversity provides higher ecosystem resilience to disturbances.
- 6. The gardening measure may also be implemented worldwide, eliminating the need to extract existing colonies for transplantation operations. At degraded reef sites, the coral gardening strategy can assist in managing human and non‐human stakeholders' requirements as is done in forest management.
3.
Sarit Lampert‐Karako Noga Stambler Don J. Katcoff Yair Achituv Zvy Dubinsky Noa Simon‐Blecher 《水产资源保护:海洋与淡水生态系统》2008,18(6):1039-1045
- 1. The symbiotic association between corals and zooxanthellae has been a major contributing factor in the success of reef‐building corals.
- 2. The diversity of zooxanthellae harboured in the hermatypic coral Stylophora pistillata in the Gulf of Eilat (Aqaba), northern Red Sea, was investigated on the basis of the length and sequence variation of the 18S small subunit ribosomal DNA. Of several clades found worldwide, only clades A and C were found to be associated with this coral species in the Gulf.
- 3. No correlation between the pink and brown colour morphs of the coral S. pistillata and the zooxanthella clade was found. Shallow‐water colonies (5 m) harbour clade A while deeper‐water colonies (17 m) harbour either clade A or C. This coral is a brooding species that associates with different zooxanthellae at different depths.
- 4. Eutrophication from fish farms did not affect clade identity associated with Stylophora.
4.
Diego Lirman Beth Orlando Silvia Maciá Derek Manzello Louis Kaufman Patrick Biber Tahzay Jones 《水产资源保护:海洋与淡水生态系统》2003,13(2):121-135
- 1. Hardbottom habitats of Biscayne Bay, a shallow lagoon adjacent to the city of Miami, Florida, USA, contain a limited number of coral species that represent a small subset of the species found at nearby offshore hardbottom and reef habitats of the Florida Reef Tract. Although the physical characteristics of this basin make it a marginal environment for coral growth, the presence of dense populations of Siderastrea radians and Porites furcata indicate that these, as well as other corals that are found at lower densities, are able to tolerate extreme and fluctuating conditions. Three factors, temperature, sedimentation, and salinity, appear to limit coral abundance, diversity, and distribution within Biscayne Bay.
- 2. Temperatures exhibit high frequencies of extreme high and low values known to cause coral stress and mortality elsewhere. Similarly, sedimentation rates are very high and sediment resuspension caused by currents, storms and boating activities commonly bury corals under sediment layers. Sediment burial was shown experimentally to influence growth and mortality of S. radians.
- 3. The salinity of Biscayne Bay is influenced by freshwater inputs from canal, sheetflow and groundwater sources that create a near‐shore environment with low mean salinity and high salinity fluctuation. Coral communities along this western margin have the lowest coral density and species richness. Chronic exposure to low salinity was shown experimentally to cause a decrease in the growth of S. radians.
- 4. The location of Biscayne Bay, downstream of a large restoration effort planned for the Everglades watershed, highlights the need to understand the relationship between the physical environment and the health of benthic communities. The data presented here provide the type of scientific information needed so that management decisions can take into account the potential impacts of human activities on the health of coral populations that are already near their tolerance limits for temperature, salinity, and sedimentation.
5.
6.
- 1. Some of the key life history characteristics that make modular marine invertebrates such as corals vulnerable to disturbance and stress are susceptibility to damage, slow growth, longevity, and philopatry. This may be particularly so for marginal populations at the limits of their range and, for instance, that are attractive to scuba divers.
- 2. In this study we examined the population structure and incidence of damage, quantified growth rates and estimated gene flow to assess the effects of divers on the deep‐water emergent populations of the fragile red coral Errina novaezelandiae in the Te Awaatu Marine Reserve in Fiordland, New Zealand.
- 3. We found that population structure in red corals is skewed, with small colonies the most abundant. Damage was up to eight times higher in dived than in non‐dived populations of red coral, and large colonies were more likely to be damaged. Growth in red corals can be high (up to 7 cm ?1), although net growth is much lower (0.7 cm yr?1) due to the effects of partial mortality. On the basis of the slow growth rate, we estimate that large corals (>20 cm diameter) will be in excess of 30 yr old. We also found high genetic subdivision among red coral populations and evidence of inbreeding, indicative of limited larval dispersal among neighbouring populations.
- 4. Overall, our results indicate the shallow‐water populations of red coral in Fiordland will be susceptible to impacts from scuba diving, and the development of a management strategy to ensure ecologically sustainable tourism and to minimize the effects of divers will be essential for their conservation.
7.
8.
9.
10.
Evelyn Valencia Erika Meerhoff Ernesto Díaz-Cabrera Felipe Guerrero Noemi Roja-Hernández Caren Vega-Retter David Veliz 《水产资源保护:海洋与淡水生态系统》2021,31(2):356-366
- Population connectivity has a fundamental role in metapopulation dynamics, with important implications in conservation. Easter Island (EI) and Salas y Gómez Island (SG) in the Pacific Ocean are ideal for the study of population connectivity because they are separated by 415 km and isolated from other islands in the Pacific Ocean by >2,000 km.
- Considering that dispersal processes could play a critical role in the persistence of its populations, the connectivity pattern of the rudderfish Kyphosus sandwicensis was evaluated between EI and SG using both a population genetics and a biophysical modelling approach.
- The variability in the control region of the mitochondrial DNA did not show a significant phylogeographical pattern, and the variability in 16 microsatellite loci suggested that individuals of K. sandwicensis located at EI and SG belong to the same genetic population. However, historical migration showed that 0.2% of the recruits at EI come from SG and that 0.15% at SG come from EI per year.
- Using simulated larval release during September and a larval development of 30 days in the plankton, biophysical modelling did not detect migration between the islands. Furthermore, self-recruitment shows interannual variation ranging from 5 to 10% of the total released larvae.
- Whereas the genetic data showed a lack of population genetic structure but low connectivity of K. sandwicensis between EI and SG, the biophysical modelling showed null movement of particles between the islands. Stochastic movement of larvae or adults could explain the pattern observed, with rafting as an example. These low-frequency and stochastic movements may be important in maintaining the cohesiveness between EI and SG.
11.
B.D. Smith G. Braulik S. Strindberg R. Mansur M.A.A. Diyan B. Ahmed 《水产资源保护:海洋与淡水生态系统》2009,19(2):209-225
- 1. Generalized additive models of sighting data for cetaceans collected during two surveys of waterways in the Sundarbans mangrove forest of Bangladesh indicated that Ganges River dolphin Platanista gangetica gangetica distribution was conditionally dependent (P<0.05) on low salinity, high turbidity, and moderate depth during both low and high freshwater flow; and Irrawaddy dolphin Orcaella brevirostris distribution was conditionally dependent (P<0.05) on low salinity during high freshwater flow, high and moderate depths during low and high freshwater flow, respectively; low and high‐low extremes of turbidity during low and high freshwater flow, respectively; and high temperature and increasing numbers of large–small channel confluences during low freshwater flow.
- 2. According to sighting data collected over a 3‐year period by the captains of three nature tourism vessels, there were significant differences between the actual and expected frequencies of Ganges River dolphin sightings and individuals according to various channel types (chi‐square=64.22, P<0.0001 and chi‐square=134.14, P<0.0001, respectively, df=6) and of Irrawaddy dolphin sightings and individuals (chi‐square=15.28, P=0.0182, and chi‐square=29.42, P<0.0001, respectively, df=6), with shared preferences for wide sinuous channels with at least two small confluences or one large confluence.
- 3. The dependency exhibited by both species for environmental characteristics associated with abundant freshwater flow, including low salinity and the availability of confluences, make them particularly vulnerable to habitat loss due to upstream water abstraction and sea‐level rise.
- 4. Although the results of this study may not affect plans for construction in India of large‐scale, inter‐basin water transfer projects that will result in further declines in freshwater flows, or decisions within the international community about CO2 emissions affecting global sea levels, they can be used to prioritize locations where protective measures could be employed to benefit the long‐term conservation of both species.
12.
13.
14.
15.
- 1. Loop models of ecological and socio‐economic systems were developed to analyse and predict the impact of a possible accidental introduction (escapes) of the abalone Haliotis discus hannai into a benthic community of north‐central Chile.
- 2. Although the ‘new’ ecological system resulting from a successful invasion of abalone would be locally stable, the establishment of a self‐enhanced dynamic of recruits would transform this into an unstable system.
- 3. The harvest of the kelp, Lessonia trabeculata and other macroalgae is not recommended because this destabilizes the system. The harvest of abalone adults is only sustainable if they do not exert a negative effect upon other native invertebrates.
- 4. The eco‐social model showed three important results: (1) if the variables ‘Price’ and ‘Farming’ are in expansion and stationary dynamics, then the models were found unstable; (2) a self‐enhanced dynamic of abalone recruits tends toward instability; and (3) the harvest of the kelp L. trabeculata and other macroalgae would be non‐sustainable.
- 5. Based on our results, the sustainable development of extensive farming of H. discus hannai in the sea would be not reached. If it is done, an intensive monitoring of the community after introduction into the system is strongly recommended. Likewise, the farming of macroalgal species (source of food for abalone) should be promoted in order to avoid harvesting of macroalgae from natural systems.
16.
17.
Leiopathes glaberrima millennial forest from SW Sardinia as nursery ground for the small spotted catshark Scyliorhinus canicula 
下载免费PDF全文
下载免费PDF全文 Alessandro Cau Maria Cristina Follesa Davide Moccia Andrea Bellodi Antonello Mulas Marzia Bo Simonepietro Canese Michela Angiolillo Rita Cannas 《水产资源保护:海洋与淡水生态系统》2017,27(3):731-735
- 相似文献
18.
- 1. Coral reefs around the world have been deteriorating over decades owing to anthropogenic pressure. In the Caribbean recent rates of decline are alarming, particularly for coral reefs under high local human impact, many of which are severely degraded, although regions with lower direct anthropogenic influence seem less affected.
- 2. Little Cayman is a relatively undeveloped island, with less than 150 permanent residents. About 20% of its reefs have been protected by no‐take marine reserves since the mid‐1980s. We analysed the dynamics of coral communities around the island from 1999 to 2004 in order to test the hypothesis that a lack of major local anthropogenic disturbances is enough to prevent decline of coral populations.
- 3. Live hard coral coverage, coral diversity, abundance, mortality, size, and prevalence of disease and bleaching were measured using the Atlantic and Gulf Rapid Reef Assessment methodology (line transects) at nine sites. Despite the apparent undisturbed condition of the island, a 40% relative reduction of mean live coral coverage (from 26% to 16%, absolute change was 10%) was recorded in five years. Mean mortality varied from year to year from 23% to 27%. Overall mean diameter and height have decreased between 6% and 15% on average (from 47 to 40 cm for diameter, and from 31 to 29 cm for height).
- 4. The relative abundance of large reef builders of the genus Montastraea decreased, while that of smaller corals of the genera Agaricia and Porites increased. Disease prevalence has increased over time, and at least one relatively large bleaching event (affecting 10% of the corals) took place in 2003.
- 5. Mean live coral cover decline was similar inside (from 29% to 19%) and outside (from 24% to 14%) marine no‐take reserves. No significant difference in disease prevalence or clear pattern in bleaching frequency was observed between protected and non‐protected areas. It is concluded that more comprehensive management strategies are needed in order to effectively protect coral communities from degradation.
19.
- 1. Rapid assessment protocols for determining and monitoring the status of any given coral reef are provided and include measuring: (a) standing stocks of functional indicator groups, (b) herbivore populations, (c) water‐column nutrient levels, (d) tissue C:N:P ratios, (e) algal physiological‐response assays, and (f) herbivory assays. These measurements can reveal quantitative tipping‐point levels beyond which resilience to undesirable phase shifts begins to become critically reduced. Universal tipping‐point approximations are reviewed for inorganic nutrients, and posited for the first time for herbivory.
- 2. The relative roles of top‐down and bottom‐up controls in determining benthic community structure and the health of coral reefs are especially important management concerns. This paper specifically addresses the top‐down effects of herbivory and bottom‐up effects of nutrient enrichment on critical indicator groups, i.e. reef‐building corals, crustose coralline algae, dense turf algae and frondose macroalgae.
- 3. A predominance of (a) massive corals and calcareous coralline algae relative to frondose macroalgae and algal turfs indicates a healthy spatially heterogeneous condition reflecting low nutrients and high herbivory. An abundance of (b) frondose macroalgae illustrates the least desirable condition of elevated nutrient levels and reduced herbivory, possibly reflecting pollution in concert with destructive herbivore fishing practices. High coverage of (c) coralline algae suggests healthy high herbivory levels, but problems with elevated nutrients that are inhibitory to some corals. Domination by (d) dense turf algae indicates desirably low nutrient levels, but an inadequate herbivory component.
- 4. The fast growth and turnover rates of fleshy algae compared to other reef organisms highlight their value as early warning indicators of reef degradation.
- 5. From a management perspective, levels of herbivory and nutrients rank among the most useful quantitative indicators of coral reef resilience; whereas, the degree of degradation and mortality are inferred from the above functional indicator groups of benthic primary producers.
20.
- 1. The fauna of inland waters has the highest rates of imperilment of any ecosystems as a result of human demands and catchment manipulations. Thus, the conservation of these systems requires multi‐disciplinary and international collaboration.
- 2. In order to examine patterns of change in collaborative research we examined eight of the leading limnological journals over a 10 yr period, with another two journals examined over 5 yr.
- 3. Of the 9758 surveyed papers, single‐authored papers were proportionally the second most commonly published (N=2523: 25.86%) while dual‐authored papers accounted for the greatest number of papers (N=3517: 36.04%). There was a significant increase in collaboration and a decline in the relative proportion of single‐ (r2=0.71; P=0.00) and dual‐authored (r2=0.54; P=0.00) papers.
- 4. Collaboration between authors from different countries was recorded for 827 of the 8636 (9.58%) papers examined. While there was an annual average of 864 (8.57%) papers involving international collaboration, the range varied from 464 (5.60%: 1990) to 1374 (12.66%: 1995). There was a significant increase (r2=0.59; P=0.01) in the number of papers involving international collaboration.
- 5. ‘Third World’ contributions constituted an average of 7.64% of papers published annually, ranging from 5.32% of all papers in 1987 to 9.31% in 1994.
- 6. Roughly equal proportions of lentic, lotic and marine papers were published over the survey period. Taxonomic and estuarine research was poorly represented probably due to the many specialist journals available for such publications. The data do not support the assertion that there has been an increase in lotic research at the expense of lentic research. Indeed, our data show a significant decrease in the number of papers published relating to lotic systems (r2=0.51; P=0.02).
- 7. The future of collaborative research conducted by multi‐institutional and multi‐disciplinary teams and its significance in terms of the management and conservation of aquatic ecosystems globally is discussed.