845 resultados para Life-Space Assessment (LSA)


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Since 2001, NOAA National Centers for Coastal Ocean Science (NCCOS), Center for Coastal Monitoring and Assessment’s (CCMA) Biogeography Branch (BB) has been working with federal and territorial partners to characterize, monitor, and assess the status of the marine environment across the U.S. Virgin Islands (USVI). At the request of the St. Thomas Fisherman’s Association (STFA) and NOAA Marine Debris Program, CCMA BB developed new partnerships and novel technologies to scientifically assess the threat from derelict fish traps (DFTs). Traps are the predominant gear used for finfish and lobster harvesting in St. Thomas and St. John. Natural phenomena (ground swells, hurricanes) and increasing competition for space by numerous user groups have generated concern about increasing trap loss and the possible ecological, as well as economic, ramifications. Prior to this study, there was a general lack of knowledge regarding derelict fish traps in the Caribbean. No spatially explicit information existed regarding fishing effort, abundance and distribution of derelict traps, the rate at which active traps become derelict, or areas that are prone to dereliction. Furthermore, there was only limited information regarding the impacts of derelict traps on natural resources including ghost fishing. This research identified two groups of fishing communities in the region: commercial fishing that is most active in deeper waters (30 m and greater) and an unknown number of unlicensed subsistence and or commercial fishers that fish closer to shore in shallower waters (30 m and less). In the commercial fishery there are an estimated 6,500 active traps (fish and lobster combined). Of those traps, nearly 8% (514) were reported lost during the 2008-2010 period. Causes of loss/dereliction include: movement of the traps or loss of trap markers due to entanglement of lines by passing vessels; theft; severe weather events (storms, large ground swells); intentional disposal by fishermen; traps becoming caught on various bottom structures (natural substrates, wrecks, etc.); and human error.

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This report contains a chemical and biological characterization of sediments from the St. Thomas East End Reserves (STEER) in St. Thomas, U.S. Virgin Islands (USVI). The STEER Management Plan (published in 2011) identified chemical contaminants and habitat loss as high or very high threats and called for a characterization of chemical contaminants as well as an assessment of their effects on natural resources. The baseline information contained in this report on chemical contaminants, toxicity and benthic infaunal community composition can be used to assess current conditions, as well as the efficacy of future restoration activities. In this phase of the project, 185 chemical contaminants, including a number of organic (e.g., hydrocarbons and pesticides) and inorganic (e.g., metals) compounds, were analyzed from 24 sites in the STEER. Sediments were also analyzed using a series of toxicity bioassays, including amphipod mortality, sea urchin fertilization impairment, and the cytochrome P450 Human Reporter Gene System (HRGS), along with a characterization of the benthic infaunal community. Higher levels of chemical contaminants were found in Mangrove Lagoon and Benner Bay in the western portion of the study area than in the eastern area. The concentrations of polychlorinated biphenyls (PCBs), DDT (dichlorodiphenyltrichloroethane), chlordane, zinc, copper, lead and mercury were above a NOAA sediment quality guideline at one or more sites, indicating impacts may be present in more sensitive species or life stages in the benthic environment. Copper at one site in Benner Bay, however, was above a NOAA guideline indicating that effects on benthic organisms were likely. The antifoulant boat hull ingredient tributyltin, or TBT, was found at the third highest concentration in the history of NOAA’s National Status and Trends (NS&T) Program, which monitors the Nation’s coastal and estuarine waters for chemical contaminants and bioeffects. Unfortunately, there do not appear to be any established sediment quality guidelines for TBT. Results of the bioassays indicated significant sediment toxicity in Mangrove Lagoon and Benner Bay using multiple tests. The benthic infaunal communities in Mangrove Lagoon and Benner Bay appeared severely diminished.

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The occurrence of hypoxia, or low dissolved oxygen, is increasing in coastal waters worldwide and represents a significant threat to the health and economy of our Nation’s coasts and Great Lakes. This trend is exemplified most dramatically off the coast of Louisiana and Texas, where the second largest eutrophication-related hypoxic zone in the world is associated with the nutrient pollutant load discharged by the Mississippi and Atchafalaya Rivers. Aquatic organisms require adequate dissolved oxygen to survive. The term “dead zone” is often used in reference to the absence of life (other than bacteria) from habitats that are devoid of oxygen. The inability to escape low oxygen areas makes immobile species, such as oysters and mussels, particularly vulnerable to hypoxia. These organisms can become stressed and may die due to hypoxia, resulting in significant impacts on marine food webs and the economy. Mobile organisms can flee the affected area when dissolved oxygen becomes too low. Nevertheless, fish kills can result from hypoxia, especially when the concentration of dissolved oxygen drops rapidly. New research is clarifying when hypoxia will cause fish kills as opposed to triggering avoidance behavior by fish. Further, new studies are better illustrating how habitat loss associated with hypoxia avoidance can impose ecological and economic costs, such as reduced growth in commercially harvested species and loss of biodiversity, habitat, and biomass. Transient or “diel-cycling” hypoxia, where conditions cycle from supersaturation of oxygen late in the afternoon to hypoxia or anoxia near dawn, most often occurs in shallow, eutrophic systems (e.g., nursery ground habitats) and may have pervasive impacts on living resources because of both its location and frequency of occurrence.

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This report, "Harmful Algal Bloom Management and Response: Assessment and Plan" reviews and evaluates Harmful Algal Bloom (HAB) management and response efforts, identifies current prevention, control, and mitigation programs for HABs, and presents an innovative research, event response, and infrastructure development plan for advancing the response to HABs. In December 2004, Congress enacted and the President signed into law the Harmful Algal Bloom and Hypoxia Amendments Act of 2004, (HABHRCA 2004). The reauthorization of HABHRCA acknowledged that HABs are one of the most scientifically complex and economically damaging coastal issues challenging our ability to safeguard the health of our Nation’s coastal ecosystems. The Administration further recognized the importance of HABs as a high priority national issue by specifically calling for the implementation of HABHRCA in the President’s U.S. Ocean Action Plan. HABHRCA 2004 requires four reports to assess and recommend research programs on HABs in U.S. waters. This document comprises two linked reports specifically aimed at improving HAB management and response: the Prediction and Response Report and the follow-up plan, the National Scientific Research, Development, Demonstration, and Technology Transfer (RDDTT) Plan on Reducing Impacts from Harmful Algal Blooms. This document was prepared by the Interagency Working Group on Harmful Algal Blooms, Hypoxia, and Human Health, which was chartered through the Joint Subcommittee on Ocean Science and Technology of the National Science and Technology Council and the Interagency Committee on Ocean Science and Resource Management Integration. This report complements and expands upon HAB-related priorities identified in Charting the Course for Ocean Science in the United States for the Next Decade: An Ocean Research Priorities Plan and Implementation Strategy, recently released by the Joint Subcommittee on Ocean Science and Technology. It draws from the contributions of numerous experts and stakeholders from federal, state, and local governments, academia, industry, and non-governmental organizations through direct contributions, previous reports and planning efforts, a public comment period, and a workshop convened to develop strategies for a HAB management and response plan. Given the importance of the Nation’s coastal ocean, estuaries, and inland waters to our quality of life, our culture, and the economy, it is imperative that we move forward to better understand and mitigate the impacts of HABs which threaten all of our coasts and inland waters. This report is an effort to assess the extent of federal, state and local efforts to predict and respond to HAB events and to identify opportunities for charting a way forward.

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The green sea urchin (Strongylocentrotus droebachiensis) is important to the economy of Maine. It is the state’s fourth largest fishery by value. The fishery has experienced a continuous decline in landings since 1992 because of decreasing stock abundance. Because determining the age of sea urchins is often difficult, a formal stock assessment demands the development of a size-structured population dynamic model. One of the most important components in a size-structured model is a growth-transition matrix. We developed an approach for estimating the growth-transition matrix using von Bertalanffy growth parameters estimated in previous studies of the green sea urchin off Maine. This approach explicitly considers size-specific variations associated with yearly growth increments for these urchins. The proposed growth-transition matrix can be updated readily with new information on growth, which is important because changes in stock abundance and the ecosystem will likely result in changes in sea urchin key life history parameters including growth. This growth-transition matrix can be readily incorporated into the size-structured stock assessment model that has been developed for assessing the green sea urchin stock off Maine.

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Growth, mortality and stock parameters of Johnieops sina (Cuvier) based on the data collected from 1989 to 1994 from Sassoon Dock and New Ferry Wharf landing centres of Greater Bombay has been discussed here. The von Bertallanffy's growth parameters for this species were estimated as follows, L∞= 266 mm, K=0.91 per year and W∞=193 g. This species grows to 159 and 223 mm at the end of first and second year of its life. The mortality parameters estimated were Z=6.17, M=2. 03 and F=4.14. The E and U were calculated as 0.62 and 0.63 respectively. Length cohort and Thompson Bell analyses show that there is no decline in the catches at the present level of fishing. But even by doubling the efforts the catches can go up by only 9.4 % indicating that the fishing efforts is not economical and proportional to the increase in yield.

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The Nabugabo lakes are an important source of affordable protein food in the form of fish, income, water for domestic and commercial purposes (aquaculture farm and Hotels), handcraft materials (mats, hats, roof thatch) and fishing floats and rafts. Nabugabo lakes provide employment, income and export earnings to Uganda that flow from the act of harvesting the fish. In Uganda the fisheries sector directly employs 350,000 people and indirectly 1.2 million people. In 2005, it is estimated that about 370,000 mt fish export (97-98% Nile perch) earned Uganda US $ 143 Million up from US $ 103 million in 2004 .and up from US $ 45 million in 1996. , making it almost become the first non' traditional export commodity. The Nabugabo lakes are also import for cultural values and fish species from these lakes are important in evolutionary studies. The fishery sector is therefore very important in Uganda's socio-economic life. Despite the above values to the communities and global biodiversity roles, the amount of fish caught and the number fishing fleets operating on the Nabugabo lakes to guide management of the lake are lacking. The fishery that exists in these lakes is largely for subsistence and commercial purposes specific for Lake Nabugabo based on introduced species (Nile perch and Nile Tilapia). The fish is caught using mainly gill nets and long line hooks.

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The quality and shelf-life of three freshwater fish species of Bangladesh, catla (Catla catla), magur (Clarias batrachus) and tilapia (Oreochromis niloticus) stored at room temperature and ice were evaluated. Live fishes were killed by cranial spiking and stored at room temperature (27-30 °C), ice stored immediately after death, 5 hr after death and 10 hr after death. The shelf-life and quality of the fishes were evaluated by organoleptic method, rigor-mortis studies and bacteriological assessment. Fishes kept at room temperature became organoleptically unacceptable within 16-20 hr duration. Ice stored fishes showed considerable differences in their shelf-life when icing was delayed for different duration. Shelf-life of catla ice stored immediately after death was 20 days but shelf-life reduced to 12 days when icing delayed for 10 hr after death. Similar trend was observed for two other fish species magur and tilapia. Rigor-index of the fishes stored under different conditions also considerably varied among the three fish species, particularly effect of delayed icing was very much evident. Bacteriological study showed patterns of Aerobic Plate Count (APC) at the end of shelflife study when fishes became organoleptically unacceptable were more or less similar for all the three fish species stored under different conditions. No definite pattern was observed in the generic distribution of bacteria in different fish species under different storage conditions. Micrococcus, Coryneforms, Pseudomonas and Achromobacter were the dominant groups of bacteria isolated from the fishes spoiled at room temperature and ice stored condition.

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A study was conducted at Banate Bay, Iloilo, from November 1975 to March 1976. Trials were conducted using spat collectors of four types, but no Modiolus metcalfei spat settled on any of the experimental collectors during the entire study period. Instead they attached to the exposed posterior half of the living Modiolus collected for reproductive cycle studies. The aquaculture potential of the brown mussel is considered to be low. Improvement of its production potential should be approached along the line of resource management rather than aquaculture. This management should be aimed at two objectives: (1) maintenance of enough adults on settlement surfaces, and (2) provision of space to allow new recruitments to grow. A possible solution, therefore, is controlled harvesting or thinning after the peak in the settlement season. In this manner, the chances of the mussel bed recovering year after year may be enhanced.

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Nisin is a widely used naturally occurring antimicrobial effective against many pathogenic and spoilage microorganisms. It has been proposed that reduced efficacy of nisin in foods can be improved by technologies such as encapsulation to protect it from interferences by food matrix components. The aim of this study was using of spray dried encapsulated nisin with zein in concentration of (0.15 and 0.25 g/kg) and sodium citrate (1.5 and 2.5%) and treatments with both of them to extent the shelf life of filleted trouts packaged by Modified Atmosphere Packaging (45% CO2, 50% N2 ,5% O2) and stored at 4±1 °C for 20 days. Furthermore, to evaluate the antimicrobial efficiency of encapsulated nisin and soudium citrate the trouts fillets was inoculated with Staphylococcus aureus as an index pathogenic bacteria. Assessment of chemical spoilage indexes such as (Proxide value, Thiobarbituric acid, total volatile base nitrogen and pH) , microbial parameters (Total Plate Count, Psychrotrophic count, Lactic acid bacteria count), Staphylococcus aureus cont in treatments which were inoculated with 5 logcfu/g of this bacteria and sensory evaluation of fillets including (smell, color, texture and total acceptability) was carried out in days of 0, 4, 8, 12, 16 and 20. The results revealed that treatment with both exposure of nisin and sodium citrate showed significantly lower chemical spoilage indexes in comparison with controls (vaccum packed and MAP) (P<0.05). Furthermore, (nisin 0.25 g/kg sodium citrate 2.5%) treatment which was exposed to the maximal level used of both materials was significantly the lowest treatment with (Proxide value, Thiobarbituric acid, total volatile base nitrogen and pH) of 9.95 (meq O2/kg) , 1.55 (mgMA/kg), 29.65 (mgN/100g) and 6.65 , respectively and according to the maximal recommended level of this indices , shelf life of fillets in this treatment was esstimated 20 days.The control (vaccum packed) treatment was significantly the highest treatment with (Proxide value, Thiobarbituric acid, total volatile base nitrogen and pH) of 15.17 (meq O2/kg), 3.03 (mgMA/kg), 38.4 (mgN/100g) and 6.95 , respectively and according to the maximal recommended level of this indices , shelf life of fillets in this treatment was estimated 11 days. Also, in microbial point of view (nisin 0.25 g/kg- sodium citrate 2.5%) treatment was the lowest treatment with Total Plate Count, Psychrotrophic count, Lactic acid bacteria count and Staphylococcus aureus count of 6.7, 6.83, 5.25 and 6.04 logcfu/g respectively, and conrol (vaccum packed) treatment was the highest treatment with 9.15, 9.41, 7.7 and 9.01 logcfu/g respectively. According to the lower results of chemical and microbial indices and higher sensory evaluated scores assessed in this research for encapsulated nisin in comparison with free nisin , it was concluded that encapsulation of nisin with zein capsules may improve the efficiency of nisin. The measuremented values of Mass yield, Total solids content of capsules, Encapsulation efficiency, In vitro release kinetics in 200 hour for encapsulated nisin in this study was 49.89, 62, 98.31 and 69% respectively and Encapsulated particle size was lower than 674.21 μm for 90% of particles. As a consequence, nisin , in particular encapsulated nisin, and sodium citrate alone or together with and Modified Atmosphere packaging might be considered as effective tools in preventing the quality degradation of the fillets, resulting in an extension of their shelf life.

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Reusing steel and aluminum components would reduce the need for new production, possibly creating significant savings in carbon emissions. Currently, there is no clearly defined set of strategies or barriers to enable assessment of appropriate component reuse; neither is it possible to predict future levels of reuse. This work presents a global assessment of the potential for reusing steel and aluminum components. A combination of top-down and bottom-up analyses is used to allocate the final destinations of current global steel and aluminum production to product types. A substantial catalogue has been compiled for these products characterizing key features of steel and aluminum components including design specifications, requirements in use, and current reuse patterns. To estimate the fraction of end-of-life metal components that could be reused for each product, the catalogue formed the basis of a set of semistructured interviews with industrial experts. The results suggest that approximately 30% of steel and aluminum used in current products could be reused. Barriers against reuse are examined, prompting recommendations for redesign that would facilitate future reuse.

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Space heating accounts for a large portion of the world's carbon dioxide emissions. Ground Source Heat Pumps (GSHPs) are a technology which can reduce carbon emissions from heating and cooling. GSHP system performance is however highly sensitive to deviation from design values of the actual annual energy extraction/rejection rates from/to the ground. In order to prevent failure and/or performance deterioration of GSHP systems it is possible to incorporate a safety factor in the design of the GSHP by over-sizing the ground heat exchanger (GHE). A methodology to evaluate the financial risk involved in over-sizing the GHE is proposed is this paper. A probability based approach is used to evaluate the economic feasibility of a hypothetical full-size GSHP system as compared to four alternative Heating Ventilation and Air Conditioning (HVAC) system configurations. The model of the GSHP system is developed in the TRNSYS energy simulation platform and calibrated with data from an actual hybrid GSHP system installed in the Department of Earth Science, University of Oxford, UK. Results of the analysis show that potential savings from a full-size GSHP system largely depend on projected HVAC system efficiencies and gas and electricity prices. Results of the risk analysis also suggest that a full-size GSHP with auxiliary back up is potentially the most economical system configuration. © 2012 Elsevier Ltd.

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Terms such as Integrated Assessment and Sustainability Assessment are used to label 'new' approaches to impact assessment that are designed to direct planning and decision-making towards sustainable development (SD). Established assessment techniques, such as EIA and SEA, are also widely promoted as SD 'tools'. This paper presents the findings of a literature review undertaken to identify the features that are typically promoted for improving the SD-directedness of assessments. A framework is developed which reconciles the broad range of emerging approaches and tackles the inconsistent use of terminology. The framework comprises a three-dimensional space defined by the following axes: the comprehensiveness of the SD coverage; the degree of 'integration' of the techniques and themes; and the extent to which a strategic perspective is adopted. By applying the framework, assessment approaches can be positioned relative to one another, enabling comparison on the basis of substance rather than semantics. © 2007 Elsevier Inc. All rights reserved.

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Plastics packaging is ubiquitous in the food industry, fulfilling a range of functions including a significant role in reducing food waste. The public perception of packaging, however, is dominated by end-of-life aspects, when the packaging becomes waste often found littering urban, rural and marine environments. A balanced analysis of the role of packaging demands that the whole lifecycle is examined, looking not only at the packaging itself but also at the product being packaged. This paper focuses on packaging in the meat and cheese industry, analysing the impact of films and bags. The functions of packaging are defined and the environmental impact of delivering these functions is assessed. The influence of packaging on levels of waste and energy consumption elsewhere in the system is examined, including the contentious issue of end-of-life for packaging. Strategies for minimizing the environmental impact of the packaging itself involve reduction in the amount of material used (thinner packaging), rather than emphasizing end-of-life issues. Currently, with polymer recycling not at a high level, evidence suggests that this strategy is justifiable. Biodegradable polymers may have some potential for improving environmental performance, but are still problematic. The conclusion is that although current packaging is in some ways wasteful and inefficient, the alternatives are even less desirable. © 2013 Elsevier B.V. All rights reserved.

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The persistence time and risk of microcystin-RR (MC-RR) in cropland via irrigation were investigated under laboratory conditions. In order to evaluate the efficiency of the potential adsorption and biodegradation of MC-RR in cropland and the persistence time of MC-RR for crop irrigation, high performance liquid chromatography (HPLC) was used to quantify the amount of MC-RR in solutions. Our study indicated that MC-RR could be adsorbed and biodegraded in cropland soils. MC-RR at 6.5 mg/L could be completely degraded within 6 days with a lag phase of 1 - 2 days. In the presence of humic acid, the same amount of MC-RR could be degraded within 4 days without a lag phase. Accordingly, the persistence time of MC-RR in cropland soils should be about 6 days. This result also suggested the beneficial effects of the organic fertilizer utilization for the biodegradation of MC-RR in cropland soils. Our studies also demonstrated that MC-RR at low concentration (< 10 mu g/L) could accelerate the growth of plants, while high concentration of MC-RR (> 100 mu g/L) significantly inhibited the growth of plants. High sensitivity of the sprouting stage plants to MC-RR treatments as well as the strong inhibitory effects resulting from prolonged irrigation further indicated that this MC-RR growth-inhibition may vary with the duration of irrigation and life stage of the plants. (c) 2007 Published by Elsevier Ltd.