8 resultados para ACTIVITY ANALYSIS

em Aquatic Commons


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Models that help predict fecal coliform bacteria (FCB) levels in environmental waters can be important tools for resource managers. In this study, we used animal activity along with antibiotic resistance analysis (ARA), land cover, and other variables to build models that predict bacteria levels in coastal ponds that discharge into an estuary. Photographic wildlife monitoring was used to estimate terrestrial and aquatic wildlife activity prior to sampling. Increased duck activity was an important predictor of increased FCB in coastal ponds. Terrestrial animals like deer and raccoon, although abundant, were not significant in our model. Various land cover types, rainfall, tide, solar irradiation, air temperature, and season parameters, in combination with duck activity, were significant predictors of increased FCB. It appears that tidal ponds allow for settling of bacteria under most conditions. We propose that these models can be used to test different development styles and wildlife management techniques to reduce bacterial loading into downstream shellfish harvesting and contact recreation areas.

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In line with its mandate of poverty reduction and sustainable development, the WorldFish Center is orienting its research towards high impact scientific activity. Identifying such activities is the task of prospective impact assessment, in turn based on impact pathway analysis. The paper describes a framework for analyzing benefits from aquatic resources research, the relevant research categories, pathways to impact by category, and indicators along each pathway that can be estimated in order to quantify probable research impact.

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Biological implications of two managment options (the closed corridor and the recommended shortened season (Option 7) options) for the Atlantic menhaden, Brevoortia tyrannus, fishery are reported based on purse-seine landings and port sampling data from 1970 to 1984 and captain's daily fishing reports from 1978 to 1982. Large catches of age-O menhaden raise concern for growth overfishing. Area-specific yield-per-recruit analyses are used to investigate the biological consequences of these management options. The closed corridor option indicates coastwide gains in yield-per-recruit ranging from 0.3 to 7.2% depending on changes in fishing activity with most areas showing gains. The shortened fishing season indicates coastwide gains in yield per recruit ranging from O. 4 to 10.2% depending onf ishing year with most geographic areas showing gains. The shortened fishing season option offers the greatest gains when large numbers ofy oung menhaden would be caught late in the fishing year, while gains from the closed corridor option depend on how the fishing fleet responds to that management plan. The shortened season offers greater potential coastwide gains to the fishery, but also may result in greater losses to the North Carolina fall fishery. The analytical approach is applicable to the management of other coastal migratory fish stocks that fall under the Atlantic States Marine Fisheries Commission or other interstate management groups.

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Land-based pollution is commonly identified as a major contributor to the observed deterioration of shallow-water coral reef ecosystem health. Human activity on the coastal landscape often induces nutrient enrichment, hypoxia, harmful algal blooms, toxic contamination and other stressors that have degraded the quality of coastal waters. Coral reef ecosystems throughout Puerto Rico, including Jobos Bay, are under threat from coastal land uses such as urban development, industry and agriculture. The objectives of this report were two-fold: 1. To identify potentially harmful land use activities to the benthic habitats of Jobos Bay, and 2. To describe a monitoring plan for Jobos Bay designed to assess the impacts of conservation practices implemented on the watershed. This characterization is a component of the partnership between the U.S. Department of Agriculture (USDA) and the National Oceanic and Atmospheric Administration (NOAA) established by the Conservation Effects Assessment Project (CEAP) in Jobos Bay. CEAP is a multi-agency effort to quantify the environmental benefits of conservation practices used by private landowners participating in USDA programs. The Jobos Bay watershed, located in southeastern Puerto Rico, was selected as the first tropical CEAP Special Emphasis Watershed (SEW). Both USDA and NOAA use their respective expertise in terrestrial and marine environments to model and monitor Jobos Bay resources. This report documents NOAA activities conducted in the first year of the three-year CEAP effort in Jobos Bay. Chapter 1 provides a brief overview of the project and background information on Jobos Bay and its watershed. Chapter 2 implements NOAA’s Summit to Sea approach to summarize the existing resource conditions on the watershed and in the estuary. Summit to Sea uses a GIS-based procedure that links patterns of land use in coastal watersheds to sediment and pollutant loading predictions at the interface between terrestrial and marine environments. The outcome of Summit to Sea analysis is an inventory of coastal land use and predicted pollution threats, consisting of spatial data and descriptive statistics, which allows for better management of coral reef ecosystems. Chapters 3 and 4 describe the monitoring plan to assess the ecological response to conservation practices established by USDA on the watershed. Jobos Bay is the second largest estuary in Puerto Rico, but has more than three times the shoreline of any other estuarine area on the island. It is a natural harbor protected from offshore wind and waves by a series of mangrove islands and the Punta Pozuelo peninsula. The Jobos Bay marine ecosystem includes 48 km² of mangrove, seagrass, coral reef and other habitat types that span both intertidal and subtidal areas. Mapping of Jobos Bay revealed 10 different benthic habitats of varying prevalence, and a large area of unknown bottom type covering 38% of the entire bay. Of the known benthic habitats, submerged aquatic vegetation, primarily seagrass, is the most common bottom type, covering slightly less than 30% of the bay. Mangroves are the dominant shoreline feature, while coral reefs comprise only 4% of the total benthic habitat. However, coral reefs are some of the most productive habitats found in Jobos Bay, and provide important habitat and nursery grounds for fish and invertebrates of commercial and recreational value.

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Tag release and recapture data of bigeye (Thunnus obesus) and yellowfin tuna (T. albacares) from the Hawaii Tuna Tagging Project (HTTP) were analyzed with a bulk transfer model incorporating size-specific attrition to infer population dynamics and transfer rates between various fishery components. For both species, the transfer rate estimates from the offshore handline fishery areas to the longline fishery area were higher than the estimates of transfer from those same areas into the inshore fishery areas. Natural and fishing mortality rates were estimated over three size classes: yellowfin 20–45, 46–55, and ≥56 cm and bigeye 29–55, 56–70, and ≥71 cm. For both species, the estimates of natural mortality were highest in the smallest size class. For bigeye tuna, the estimates decreased with increasing size and for yellowfin tuna there was a slight increase in the largest size class. In the Cross Seamount fishery, the fishing mortality rate of bigeye tuna was similar for all three size classes and represented roughly 12% of the gross attrition rate (includes fishing and natural mortality and emigration rates). For yellowfin tuna, fishing mortality ranged between 7% and 30%, the highest being in the medium size class. For both species, the overall attrition rate from the entire fishery area was nearly the same. However, in the specific case of the Cross Seamount fishery, the attrition rate for yellowfin tuna was roughly twice that for bigeye. This result indicates that bigeye tuna are more resident at the Seamount than yellowfin tuna, and larger bigeye tunas tend to reside longer than smaller individuals. This may result in larger fish being more vulnerable to capture in the Seamount fishery. The relatively low level of exchange between the Sea-mount and the inshore and longline fisheries suggests that the fishing activity at the Seamount need not be of great management concern for either species. However, given that the current exploitation rates are considered moderate (10–30%), and that Seamount aggregations of yellowfin and bigeye tuna are highly vulnerable to low-cost gear types, it is recommended that further increases in fishing effort for these species be monitored at Cross Seamount.

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This publication is based on materials covered and outputs generated during the Workshop on Risk Assessment Methodologies and Tools for Aquaculture in Sub-Saharan Africa, which was jointly held by WorldFish and FAO in Siavonga, Zambia on 28 June - 2 July 2010. The workshop was delivered as a training exercise to 17 participants from seven sub-Saharan countries and was designed to highlight current methodologies and tools available for environmental risk analysis in aquaculture development. A key focus of the workshop was to encourage participants to consider hypothetical but realistic scenarios and to discuss issues relevant to evaluating the environmental risks of a given activity or scenario. This publication presents selected scenarios from the workshop and the outcomes of the deliberative process as developed by the participants. This publication is factual but not comprehensive, therefore any statements or estimations of risk do not represent the actual risks arising from the described scenario. It is intended to serve as an easily readable introduction to risk analysis, highlighting worked examples that will provide guidance on how a risk analysis may be approached in a similar situation.

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Identification of venomous species of Persian Gulf cone snails and characterization of venom composition and their features is so important from the point of medical importance. Marine cone snails from the genus Conus are estimated to consist of up to 700 species. The venom of cone snails has yielded a rich source of novel neuroactive peptides or conotoxins. The present study was aimed to study the analgesic effect of Persian Gulf Conus textile and its comparison with morphine in mouse model. The specimens of Conus textile were collected of Larak Island from depth of 7 m. The collected samples were transferred to laboratory alive and were stored at -700 c. he veno s ducts were separated and ho ogenized with deionized water he ixture centrifuged at rp for inutes upernatant was considered as extracted veno and stored at - C after lyophylization. The protein profile of venom determined by using SDS-PAGE and HPLC used to investigate the extracted venom and to evaluate the analgesic activity, formalin test was carried out. SDS-PAGE indicated several bands ranged between 6 and 250 kDa. Chromatogram of the venom demonstrated more than 44 large and small fractions. The amount of 10 ng of Conus crude venom and analgesic peptide showed the best anti-pain activity in formalin test. No death observed up to 100 mg/kg, which is 250,000 times higher than the effective dose.Venom characterization of Persian Gulf Conus textile may be of medical importance and potential for new pharmaceutical drugs as well.

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Green scat namely as Scatophagus argus argus is a venomous aquarium fish belonging to Scatophagidae family. It can induce painful wounds in injured hand with partial paralysis to whom that touch the spines. Dorsal and ventral rough spines contain cells that produce venom with toxic activities. According to unpublished data collected from local hospitals in southern coastal region of Iran, S. argus is reported as a venomous fish. Envenomation induces clinical symptoms such as local pain, partial paralysis, erythema and itching. In the present study green scat (spotted scat) was collected from Persian Gulf coastal waters. SDS-PAGE indicated 12 distinct bands in the venom ranged between 10-250 KDa. The crude venom had hemolytic activity on human erythrocytes (1%) with an LC100 (Lytic Concentration) of about 1.7 μg. The crude venom can release 813 μg proteins from 0.5% casein. Phospholipase C activity was recorded at 3.125 μg of total venom. Our findings showed that the edematic activity remained over 48 h after injection. The purification of the venom was done by HPLC and 30 peaks were obtained within 80 min but only one peak in 68 min retention time showed hemolytic activity at 90% acetonitril was isolated. The area percentage of the hemolytic protein showed that this hemolytic protein consist of 32 percent of total proteins and its molecular weight was 72 KDa in SDS_PAGE. The results demonstrated that crude venom extracted from Iranian coastal border has different toxic and enzymatic activities.