119 resultados para Special aspects of forestry, Includes carbon sequestration, fire management, grazing,, ,pping, remote sensing and more


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Phosphorus is an essential element for living organisms and exists in waterbodies as dissolved and particulate forms. Phosphorus is required for optimum growth, feed efficiency, bone development and maintenance of acid-base regulation in fish. The presence of high concentration of phosphates in water may indicate presence of pollution as it may accelerate plant growth and disrupt the aquatic ecosystem thereby benefiting certain species and altering species diversity in affected areas. Eutrophication of waterbodies is often correlated with the phosphorus loading into the environment and aquaculture has been identified as one of the sources of phosphorus pollution. Details of the impacts of eutrophication is given in Bernhardt (1981). Phosphorus must be provided in fish feed because of its low concentration in water. Studies made in Europe and Northern America have revealed a phosphorus surplus in most commercial feeds which is above actual requirements; or is supplied in a form which is unavailable to the fish. Surplus phosphorus is excreted, while unavailable phosphorus is passed out in the feces. Discharge of phosphorus from fish farms and hatchery effluents have caused phosphorus pollution in Nordic countries, North America and Europe. This article examines the path of phosphorus pollution, quantification/prediction of phosphorus load from aquaculture and remedial measures.

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The biography of Charles Bradford Hudson that follows this preface had its seeds about 1965 when I (VGS) was casually examining the extensive files of original illustrations of fishes stored in the Division of Fishes, National Museum of Natural History, Smithsonian Institution. I happened upon the unpublished illustration of a rainbow trout by Hudson and was greatly impressed with its quality. The thought occurred to me then that the artist must have gone on to do more than just illustrate fishes. During the next 20 years I occasionally pawed through those files, which contained the work of numerous artists, who had worked from 1838 to the present. In 1985, I happened to discuss the files with my supervisor, who urged me to produce a museum exhibit of original fish illustrations. This I did, selecting 200 of the illustrations representing 21 artists, including, of course, Hudson. As part of the text for the exhibit, Drawn from the Sea, Art in the Service of Ichthyology, I prepared short biographies of each of the artists. The exhibit, with an available poster, was shown in the Museum for six months, and a reduced version was exhibited in U.S. and Canadian museums during the next 3 years.

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This is the report on the Fisheries Aspects of North West Water Authority Schemes to Increase Water Abstraction in West Cumbria by the Egremont and District Anglers’ Association. Existing river pollution and water abstraction in the Ennerdale Lake-River Ehen system is shown to have caused a major deterioration in the conditions in the Ehen fishery. This is reflected by the fact that catches of salmon, sea trout and smelts on the Ehen have all fallen to roughly 6% of the 1965 level; wich is far worse than the deterioration shown in salmon catches for S. W. Cumberland as a whole. Recommendations are made, in the light of proposals by North West Water Authority to increase water abstraction in West Cumbria, to prevent further deterioration in the Ehen fishery in the short term and to improve the situation in the longer term. It contains sections on pollution, water abstraction and fisheries background, flow statistics for and discussion of high water-droughts on the River Ehen, effects of droughts on Tidal Water and a discussion of N.W.W.A. Paper entitled `Water Resources in West Cumbria’ in the light of conditions on the River Ehen.

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In late 2012, a governance assessment was carried out as part of the diagnosis phase of rollout of the CGIAR Aquatic Agricultural Systems Program in Malaita Hub in Solomon Islands. The purpose of the assessment was to identify and provide a basic understanding of essential aspects of governance related to Aquatic Agricultural Systems in general, and more specifically as a case study in natural resource management. The underlying principles of the approach we have taken are drawn from an approach known as “Collaborating for Resilience” (CORE), which is based on bringing all key stakeholders into a process to ensure that multiple perspectives are represented (a listening phase), that local actors have opportunities to influence each other’s understanding (a dialogue phase), and that ultimately commitments to action are built (a choice phase) that would not be possible through an outsider’s analysis alone. This report begins to address governance from an AAS perspective, using input from AAS households and other networked stakeholders. We attempt to summarize governance issues that are found not only within the community but also, and especially, those that are beyond the local level, both of which may need to be addressed by the AAS program.

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