11 resultados para Close and open communion.

em Aquatic Commons


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The community structure of fishes associated with pelagic Sargassum spp. and open water lacking Sargassum was examined during summer and fall cruises, 1999–2003, in the Gulf Stream off North Carolina. Significantly more individual fishes (n= 18,799), representing at least 80 species, were collected from samples containing Sargassum habitat, compared to 60 species (n=2706 individuals) collected from openwater habitat. The majority (96%) of fishes collected in both habitats were juveniles, and planehead filefish (Stephanolepis hispidus) dominated both habitats. Regardless of sampling time (day or night), Sargassum habitat yielded significantly higher numbers of individuals and species compared with open-water collections. Overall, fishes collected by neuston net tows from Sargassum habitat were significantly larger in length than fishes collected from open-water habitat with neuston nets. A significant positive, linear relationship existed between numbers of fishes and the quantity of Sargassum collected by neuston net. Underwater video recordings indicated a layered structure of fishes among and below the algae and that smaller fishes were more closely associated with the algae than larger fishes. Observations of schooling behaviors of filefishes (Monacanthidae), dolphinfish (Coryphaena hippurus), and jacks (Carangidae), and fish-jellyfish associations were also recorded with an underwater video camera. Our data indicate that Sargassum provides a substantial nursery habitat for many juvenile fishes off the U.S. southeast coast.

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Approximately two-thirds of coastal and Great Lakes states have some type of shoreline construction setback or construction control line requiring development to be a certain distance from the shoreline or other coastal feature (OCRM, 2008). Nineteen of 30 coastal states currently use erosion rates for new construction close to the shoreline. Seven states established setback distances based on expected years from the shoreline: the remainder specify a fixed setback distance (Heinz Report, 2000). Following public hearings by the County of Kauai Planning Commission and Kauai County Council, the ‘Shoreline Setback and Coastal Protection Ordinance’ was signed by the Mayor of Kauai on January 25, 2008. After a year of experience implementing this progressive, balanced shoreline setback ordinance several amendments were recently incorporated into the Ordinance (#887; Bill #2319 Draft 3). The Kauai Planning Department is presently drafting several more amendments to improve the effectiveness of the Ordinance. The intent of shoreline setbacks is to establish a buffer zone to protect shorefront development from loss due to coastal erosion - for a period of time; to provide protection from storm waves; to allow the natural dynamic cycles of erosion and accretion of beaches and dunes to occur; to maintain beach and dune habitat; and, to maintain lateral beach access and open space for the enjoyment of the natural shoreline environment. In addition, a primary goal of the Kauai setback ordinance is to avoid armoring or hardening of the shore which along eroding coasts has been documented to ultimately eliminate the fronting beach. (PDF contains 4 pages)

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Limnological studies in Lake Victoria (Kenyan portion) have been sporadic. Water quality and nutrient dynamics studies are being undertaken in fifteen sampling sites that have been divided into four ecological zones namely: Nyanza Gulf, Rusinga Channel, open waters inshore and open waters. The ongoing study will show how the physical and chemical paramenters affect fish distribution and abundance.

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Libraries have long held an established role in the scholarly research process; however the process of scholarly communication is evolving. Citation management software, institutional repositories, open access and open data mandates have opened up new opportunities and new challenges. Researchers have more responsibility for managing their work, but less time to do it. Libraries are struggling to remain an active part of the scholarly communication process. It has become increasingly difficult for institutions to identify their scholarly output. This presentation will show how MBLWHOI is attempting to meet this challenge with the implementation of, Bibapp, an open source tool to manage campus research.

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Technological innovation has made it possible to grow marine finfish in the coastal and open ocean. Along with this opportunity comes environmental risk. As a federal agency charged with stewardship of the nation’s marine resources, the National Oceanic and Atmospheric Administration (NOAA) requires tools to evaluate the benefits and risks that aquaculture poses in the marine environment, to implement policies and regulations which safeguard our marine and coastal ecosystems, and to inform production designs and operational procedures compatible with marine stewardship. There is an opportunity to apply the best available science and globally proven best management practices to regulate and guide a sustainable United States (U.S.) marine finfish farming aquaculture industry. There are strong economic incentives to develop this industry, and doing so in an environmentally responsible way is possible if stakeholders, the public and regulatory agencies have a clear understanding of the relative risks to the environment and the feasible solutions to minimize, manage or eliminate those risks. This report spans many of the environmental challenges that marine finfish aquaculture faces. We believe that it will serve as a useful tool to those interested in and responsible for the industry and safeguarding the health, productivity and resilience of our marine ecosystems. This report aims to provide a comprehensive review of some predominant environmental risks that marine fish cage culture aquaculture, as it is currently conducted, poses in the marine environment and designs and practices now in use to address these environmental risks in the U.S. and elsewhere. Today’s finfish aquaculture industry has learned, adapted and improved to lessen or eliminate impacts to the marine habitats in which it operates. What progress has been made? What has been learned? How have practices changed and what are the results in terms of water quality, benthic, and other environmental effects? To answer these questions we conducted a critical review of the large body of scientific work published since 2000 on the environmental impacts of marine finfish aquaculture around the world. Our report includes results, findings and recommendations from over 420 papers, primarily from peer-reviewed professional journals. This report provides a broad overview of the twenty-first century marine finfish aquaculture industry, with a targeted focus on potential impacts to water quality, sediment chemistry, benthic communities, marine life and sensitive habitats. Other environmental issues including fish health, genetic issues, and feed formulation were beyond the scope of this report and are being addressed in other initiatives and reports. Also absent is detailed information about complex computer simulations that are used to model discharge, assimilation and accumulation of nutrient waste from farms. These tools are instrumental for siting and managing farms, and a comparative analysis of these models is underway by NOAA.

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Since 1999, NOAA’s Center for Coastal Monitoring and Assessment, Biogeography Branch (CCMA-BB) has been working with federal and territorial partners to characterize monitor and assess the status of the marine environment in southwestern Puerto Rico. This effort is part of the broader NOAA Coral Reef Conservation Program’s (CRCP) National Coral Reef Ecosystem Monitoring Program (NCREMP). With support from CRCP’s NCREMP, CCMA conducts the “Caribbean Coral Reef Ecosystem Monitoring project” (CREM) with goals to: (1) spatially characterize and monitor the distribution, abundance and size of marine fauna associated with shallow water coral reef seascapes (mosaics of coral reefs, seagrasses, sand and mangroves); (2) relate this information to in situ fine-scale habitat data and the spatial distribution and diversity of habitat types using benthic habitat maps; (3) use this information to establish the knowledge base necessary for enacting management decisions in a spatial setting; (4) establish the efficacy of those management decisions; and (5) develop data collection and data management protocols. The monitoring effort of the La Parguera region in southwestern Puerto Rico was conducted through partnerships with the University of Puerto Rico (UPR) and the Puerto Rico Department of Natural and Environmental Resources (DNER). Project funding was primarily provided by NOAA CRCP and CCMA. In recent decades, scientific and non-scientific observations have indicated that the structure and function of the coral reef ecosystem in the La Parguera region have been adversely impacted by a wide range of environmental stressors. The major stressors have included the mass Diadema die off in the early 1980s, a suite of hurricanes, overfishing, mass mortality of Acropora corals due to disease and several coral bleaching events, with the most severe mass bleaching episode in 2005. The area is also an important recreational resource supporting boating, snorkeling, diving and other water based activities. With so many potential threats to the marine ecosystem several activities are underway or have been implemented to manage the marine resources. These efforts have been supported by the CREM project by identifying marine fauna and their spatial distributions and temporal dynamics. This provides ecologically meaningful data to assess ecosystem condition, support decision making in spatial planning (including the evaluation of efficacy of current management strategies) and determine future information needs. The ultimate goal of the work is to better understand the coral reef ecosystems and to provide information toward protecting and enhancing coral reef ecosystems for the benefit of the system itself and to sustain the many goods and services that it offers society. This Technical Memorandum contains analysis of the first seven years of fish survey data (2001-2007) and associated characterization of the benthos. The primary objectives were to quantify changes in fish species and assemblage diversity, abundance, biomass and size structure and to provide spatially explicit information on the distribution of key species or groups of species and to compare community structure across the seascape including fringing mangroves, inner, middle, and outer reef areas, and open ocean shelf bank areas.

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A great part of Uganda is endowed with water bodies in the forms of rivers and open water lakes. These bodies are never alone. They are either flanked or associated with plants, which are adapted to the wet conditions. They are so characteristic that they are part and parcel of the aquatic ecosystems. They occupy various positions depending on the amount of water in the relevant habitats.

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ENGLISH: The accuracy and precision of dolphin school size estimates based on aerial photograph counts were examined using data collected on recent aerial and ship surveys. These estimates were found to be accurate during a 1979research cruise aboard a tuna purse-seiner; dolphin schools were photographed from the ship’s helicopter, encircled with the purse-seine, and then counted as the dolphins were released from the net. A comparison of photographic estimates with these counts indicated that the relationship was fairly close and gave no indication of significantly differing from 1:1. During a 1980 aerial study, photographic estimates from different schools, passes, and camera formats were compared and were found to be quite precise with a standard deviation of approximately 60/0 of school size. Photographic estimates were also compared with estimates made by aerial observers. Most observers tended to underestimate school size, particularly for large schools. The variability among observers was high, indicating that observers should be individually calibrated. SPANISH: Se examinó la exactitud y la precisión de las estimaciones de la magnitud de los cardúmenes de delfines basadas en el cálculo de las fotografías aéreas, usando los datos obtenidos en los últimos reconocimientos aéreos y de los barcos. En 1979, durante un crucero de investigación en un cerquero atunero, se encontró que estas estimaciones eran acertadas; se fotografiaron los cardúmenes de delfines desde un helicóptero del barco, cercados con la red y luego se contaron a medida que se libraban los delfines de la red. Una comparación de las estimaciones fotográficas con estos cálculos indicó que la relación era bastante aproximada y no hubo indicación que se diferenció significativamente de la razón 1:1. Durante un estudio aéreo en 1980, se compararon las estimaciones fotográficas de diferentes del cardúmenes, en los pases y los formatos de las cámaras y se encontró que eran bastante precisos, con una desviación normal de cerca del 60/0 de la magnitud cardumen. Se compararon también las estimaciones fotográficas con las estimaciones realizadas por los observadores aéreos. La mayoría de los observadores tienden a subestimar la magnitud de los cardúmenes, especialmente los cardúmenes grandes. La variabilidad entre los observadores fue elevada, lo que indica que se deben calibrar individualmente los datos de observadores. (PDF contains 39 pages.)

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Management of coastal species of small cetaceans is often impeded by a lack of robust estimates of their abundance. In the Austral summers of 1997−98, 1998−99, and 1999−2000 we conducted line-transect surveys of Hector’s dolphin (Cephalorhynchus hectori) abundance off the north, east, and south coasts of the South Island of New Zealand. Survey methods were modified for the use of a 15-m sailing catamaran, which was equipped with a collapsible sighting platform giving observers an eye-height of 6 m. Eighty-six percent of 2061 km of survey effort was allocated to inshore waters (4 nautical miles [nmi] or 7.4 km from shore), and the remainder to offshore waters (4−10 nmi or 7.4–18.5 km from shore). Transects were placed at 45° to the shore and spaced apart by 1, 2, 4, or 8 nmi according to pre-existing data on dolphin density. Survey effort within strata was uniform. Detection functions for sheltered waters and open coasts were fitted separately for each survey. The effect of attraction of dolphins to the survey vessel and the fraction of dolphins missed on the trackline were assessed with simultaneous boat and helicopter surveys in January 1999. Hector’s dolphin abundance in the coastal zone to 4 nmi offshore was calculated at 1880 individuals (CV=15.7%, log-normal 95% CI=1384−2554). These surveys are the first line-transect surveys for cetaceans in New Zealand’s coastal waters.

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Pelagic fishes are not evenly dispersed in the oceans, but aggregate at distinct locations in this vast and open environment. Nomadic species such as mackerels, tunas, and sharks form assemblages at seamounts (Klimley and Butler, 1988; Fontenau, 1991). Fishermen have recognized this behavior and have placed moorings with surface buoys in deep waters to provide artificial landmarks, around which fish concentrate and are more easily captured. These fish aggregating devices (termed FADs) are common in the tropical oceans (see review, Holland, 1996). In a sense, it may only be the larger size that separates a seamount from a man-made FAD.

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The study has been undertaken in Kerala State in India with an overall objective of analyzing the bio-economic conditions of commercially exploited marine fishes for assessing their sustainability in the context of existing management practices. Maximum sustainable yield, maximum economic yield and open access levels of yield and effort were analyzed using Gompertz-Fox growth model. The study concluded that the fishing effort exceeded the economically optimal levels and there is unnecessary wastage of money, manpower and fuel in the fishing industry. The study stressed the urgent need for capture fisheries management in the State which at present follows an open access fishery where regulations exist only in the form of seasonal closure in the monsoon season.