15 resultados para POTASSIUM LAURATE-1-DECANOL-WATER
em Aquatic Commons
Resumo:
The rockfishes of the sebastid genus Sebastes are a very important fishery resource off the coasts of California and southern Oregon. How-ever, many of the 54 managed stocks of west coast rockfish have recently reached historically low population levels, leading fishery managers to re-examine current management practices. Management of rockfish stocks as multispecies aggregates, as opposed to independent stocks within the ground-fish fishery, can be more desirable when nontargeted bycatch, discard, and management complexity are considered. Rockfish assemblage structure and species co-occurrences were determined by using data from the Alaska Fisheries Science Center triennial continental shelf bottom trawl survey. The weight of rockfish species in trawl catches was expressed as a catch-per-unit-of-effort (CPUE) statistic, from which species spatial distributions, overlaps, diversity, and richness were analyzed. Multidimensional scaling of transformed CPUE data was employed in indirect gradient and multivariate partitioning analyses to quantify assemblage relationships. Results indicated that rockfish distributions closely match the bathymetry of coastal waters. Indirect gradient analysis suggested that depth and latitude are the principal factors in structuring the spatial distributions of rockfish on trawlable habitat. In addition, four assemblages were identified through the joint evaluation of species’ distributions and multivariate partitioning analyses: 1) deep-water slope; 2) northern shelf; 3) southern shelf; and 4) nearshore. The slope, shelf, and near-shore groups are found in depth ranges of 200–500 m, 100–250 m, and 50–150 m, respectively. The division of northern and southern shelf assemblages occurs over a broad area between Cape Mendocino and Monterey Canyon. The results of this analysis are likely to have direct application in the management of rockfish stocks off the coasts of southern Oregon and California.
Resumo:
This paper presents a resume of the work carried on the production of 10 million major carp fry by stocking at the rate of 10 million spawn per hectare in 38 nursery ponds covering 2.1 ha. water spread area at Khutelabhata fish seed farm, Durg, Madhya Pradesh. Observations made on the effect of various types of feed on survival and growth rate of Indian Major carp fry in nurseries are reported. Physico-chemical parameters and plankton populations in the three sets of nurseries are given. The experiments indicates that optimum survival rate of fry can be obtained by feeding tender spawn with animal protein feed. The economic viability of the experiment discussed shows that for a little increase in the expenditure on improved artificial food the survival and growth of fry can be enhanced.
Resumo:
The objectives of the study were to find out the proportion of water to fish fins, skin and bones that would give a good gel and to determine the effect of a combination of fish water and commercial crude agar on the water stability of the prawn diet. Under the conditions of the experiments it was concluded: (1) Fish water and commercial agar or agar bar gave the most stable pellet, 65% water stability; (2) a strong gel is obtained when one part shark fin is boiled in 1.5 parts water; (3) more fish water can be obtained from guitar fish than from shark fish.
Resumo:
Aquaculture in the Philippines is a long-standing activity but has witnessed relatively recent, rapid, technical change with the introduction of hatchery technology and commercial feed-mills changing the production possibilities for a fishpond operator. We are confronted with a diversity of aquaculture practices in the coastal areas of the Philippines, with new technologies being incorporated into more traditional systems. As a first step to understanding the sector, we therefore present a typology of farming systems with the motivation of generating domains (farm “types”) over which we can compare performance on a number of indicators. Our typology, restricted to brackish-water pond systems, is constructed using multivariate methods (principal components analysis, cluster analysis). Eight variables are used relating to the management of the farm across all the major factors of production. A stratified net sample of 136 observations provides the data for the analysis, from a farm-level survey carried out between January and June 2003 in the two main brackish-water production regions in the Philippines. We define five farm types from this analysis. In later work we will show how the use of this typology can be used for comparative study of economic, social and ecological performance at the farm-level. [PDF contains 42 pages]
Resumo:
Four groups of brackishwater catfish were fed four diets: N.F. (NIOMR formula 1 feed), A. B. and C. for seven weeks. Feeds N.F., A., B and C. contained 1.21% fish oil + 5.59% vegetable oil; 1.21% fish oil + 7.39% vegetable oil; 1.21% fish oil + 9.09% vegetable oil; 1.21% fish oil + 10.89% vegetable oil respectively. Results of feeding trial showed that growth was best in the group fed diets containing 10.89% vegetable oil and least in those containing 9.09% vegetable oil
Resumo:
In the waterbodies of central Russia, the Urals and western Siberia four species of Crustacea, related to the genus Mesocyclops, are widely distributed: M. (s.str.) leuckarti (Claus), M. (Thermocyclops) oithonoides Sars, [M.](Th.) crassus (Fisch.) and M. (Th.) dybowskii (Lande). Numbers and biomass of Mesocyclops oithonoides in the pelagic water of various water-bodies of the Urals are presented and observations on the above mentioned species are discussed.
Resumo:
When salmonid redds are disrupted by spates, the displaced eggs will drift downstream. The mean distance of travel, the types of locations in which the eggs resettle and the depth of reburial of displaced eggs are not known. Investigation of these topics under field conditions presents considerable practical problems, though the use of artificial eggs might help to overcome some of them. Attempts to assess the similarities and/or differences in performance between real and artificial eggs are essential before artificial eggs can validly be used to simulate real eggs. The present report first compares the two types of egg in terms of their measurable physical characteristics (e.g. dimensions and density). The rate at which eggs fall in still water will relate to the rate at which they are likely to resettle in flowing water in the field. As the rate of fall will be influenced by a number of additional factors (e.g. shape and surface texture) which are not easily measured directly, the rates of fall of the two types of egg have been compared directly under controlled conditions. Finally, comparisons of the pattern of settlement of the two types of egg in flowing water in an experimental channel have been made. Although the work was primarily aimed at testing the value of artificial eggs as a simulation of real eggs, several side issues more directly concerned with the properties of real eggs and the likely distance of drift in natural streams have also been explored. This is the first of three reports made on this topic by the author in 1984.
Resumo:
This dataset provides raw data of chemical analyses made during studies on seasonal variations of some major ions in the stream water of the River Duddon in Cumbria. Measurements of sodium, calcium, potassium, magnesium and chloride ions and pH were taken at 5 stations in the River Duddon between January 1970 and August 1974.
Resumo:
This dataset provides raw data of chemical analyses made during studies on seasonal variations of some major ions in the stream water of the upper basin of the River Duddon in Cumbria. Measurements of sodium, calcium, potassium, magnesium and chloride ions and pH were taken at 26 stations in the River Duddon basin between 1972 and 1974.
Resumo:
This report describes the general background to the project, defines the stations from which data sets have been obtained and lists the available data. The project had the following aims: To develop a more accurate and less labour-intensive system for the collection and processing of water temperature data from a number of stations within a stream/river system, and to use the River North Tyne downstream of the Kielder impoundment as a test bed for the system. This should yield useful information on the effects of impoundment upon downstream water temperatures.
Resumo:
The following brief is to ensure standard criteria and format are used for the scoping and environmental assessment of water resources projects leading to the production of an environmental report or Environmental Statement. This volume is one of a series giving guidance on water resources projects. The water resources projects will predominantly comprise drought orders and permits, time limited and permanent licences. Smaller projects, such as spray irrigation licences, will not require an environmental assessment. This document forms the basis for discussions between the Environment Agency North East Region, consultees and the applicant. The process aims to produce a thorough assessment. Each section addresses consecutive elements of the assessment process. Section 2 outlines the structure for a scoping document, section 3 outlines the structure for an Environmental Statement and section 4 gives guidance on the role of an Environmental Action Plan. Appendices 1 and 2 should be used in conjunction with the scoping process and cover a wide range of aspects. However, some projects may not require all of them to be included, whilst for others, the inclusion of additional factors may be appropriate.
Resumo:
This is the Water Level Management Plan for the Rostherne Mere by the Environment Agency. The purpose of the Plan is to provide a formal basis for managing the land drainage system and water supply system of the area in order to provide a sustainable balance between the conservation and agricultural interest in the area. No changes are proposed to present water level management or maintenance practices unless and until such changes are agreed by all parties. The report contains sections on description of Site, water level management, maintenance, nature conservation, agriculture, fisheries, archaeology, water quality and water resources, development adjacent to watercourses, contingencies and objectives of the Water Level Management.
Resumo:
TOPIC 1: In terms of seasonal scale, temperature effect dominates the annual change of steric height in the open ocean whereas salinity effect controls it along the continental shelf. Large portion of the annual change of height relative to the 1000-db surface is contained in the upper 100m layer. However, in interannual scale large anomalies of steric height in the open ocean, are more often than not, caused by halosteric rather than thermosteric effect. At least in the open ocean the heights are almost totally determined by the behavior of deep water. Their interannual variability appears to be related to the cumulative effect of Eckman pumping. TOPIC 2: There is a "trend" that over the past 28 years the water at Station P has warmed. Least-square analysis indicates that this warming may be significant but shortening of the time-series data by approximately 10 years fails to show that this is the case. These "trends" have to be interpreted with care. The warming may be "apparent" in that it is not indicated clearly in the deep isopynal surfaces which, during the above period, have deepened. Thus warming at the isobaric surfaces may be the effect of the downward migration of the isopynal surfaces.
Resumo:
Remotely operated vehicle (ROV) surveys were conducted from NOAA’s state-of-the-art Fisheries Survey Vessel (FSV) Bell M. Shimada during a six-day transit November 1-5, 2010 between San Diego, CA and Seattle, WA. The objective of this survey was to locate and characterize deep-sea coral and sponge ecosystems at several recommended sites in support of NOAA’s Coral Reef Conservation Program. Deep-sea corals and sponges were photographed and collected whenever possible using the Southwest Fisheries Science Center’s (SWFSC) Phantom ROV ‘Sebastes’ (Fig. 1). The surveyed sites were recommended by National Marine Sanctuary (NMS) scientists at Monterey Bay NMS, Gulf of the Farallones NMS, and Olympic Coast NMS (Fig. 2). The specific sites were: Sur Canyon, The Football, Coquille Bank, and Olympic Coast NMS. During each dive, the ROV collected digital still images, video, navigation, and along-track conductivity-temperature-depth (CTD), and optode data. Video and high-resolution photographs were used to quantify abundance of corals, sponges, and associated fishes and invertebrates to the lowest practicable taxonomic level, and also to classify the seabed by substrate type. A reference laser system was used to quantify area searched and estimate the density of benthic fauna.
Resumo:
This ICSF Exchange Programme held in Manila is an offshoot of the Bangkok Conference on “Global Fisheries Trends and Future of Fishworkers” held on January 22–27, 1990. One of the issues raised in that conference was about the operation of Taiwanese fishing vessels outside its territorial waters and the impact of such operations on small fishermen from the countries concerned. The presence of a Taiwanese fishworker as well as an NGO supporter contributed to an enlightening discussion as the former shed light on the sad plight of Taiwanese fishworkers who are the victims of such structural problems. This meaningful exchange between groups of fishermen, particularly Taiwanese and Filipinos, resulted in the plan of the Taiwanese delegation to have some Taiwanese fishermen visit the Philippines and immerse in fishing communities.