39 resultados para History of Science and of Mathematics

em Aquatic Commons


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EXECUTIVE SUMMARY INTRODUCTION OVERVIEW OF INTERNATIONAL EBM HISTORY References CANADA Overview Activities to date Integrated Management implementation in Canada Objectives, indicators and reference points Assessment approaches Research directions for the future Management directions for the future References JAPAN Overview Conservation and sustainable use of marine living resources Harvest control by TAC system Stock Recovery Plan and effort regulation system Stock enhancement by hatchery-produced juvenile release Conservation and sustainable develop-ment on coastal waters The implementation of ecosystem-based management PEOPLE’S REPUBLIC OF CHINA Overview Current actions Output control Input control Summer fishing ban Enhance ecosystem health REPUBLIC OF KOREA Initiatives and actions of ecosystem-based management in Korea Current ecosystem-based management initiatives in Korea Precautionary TAC-based fishery management Closed fishing season/areas Fish size- and sex-controls Fishing gear design restrictions Marine protected areas (MPA) RUSSIA Existing and anticipated ecosystem-based management initiatives Issues related to the implementation of ecosystem-based management UNITED STATES OF AMERICA Definitions and approaches to ecosystem-based fishery management in the United States Present U.S. legislative mandates relating to ecosystem-based fishery management Target species Bycatch species Threatened or endangered species Habitats Food webs Ecosystems Integration of legislative mandates into an ecosystem approach Scientific issues in implementing ecosystem-based approaches References DISCUSSION AND RECOMMENDATIONS APPENDICES Appendix 10.1 Study group membership and participants Appendix 10.2 Terminology definitions Appendix 10.3 Present state of implementing ecosystem-based fishery management in Alaska: Alaska groundfish fisheries Appendix 10.4 Present state of implementing ecosystem-based fishery management off the West Coast of the United States: Pacific Coast groundfish fisheries Appendix 10.5 Descriptions of multi-species and ecosystem models developed or under development in the U.S. North Pacific region that might be used to predict effects of fishing on ecosystems Appendix 10.6 A potential standard reporting format (developed by Australia, and currently being used by the U.S.A in their contribution to this report) (83 page document)

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This report presents information on the life history, diet, abundance and distribution, and length-frequency distributions of five invertebrates in Florida Bay, Everglades National Park. Collections were made with an otter trawl in basins on a bi-monthly basis. Non-parametric statistics were used to test spatial and temporal differences in the abundance of invertebrates when numbers were appropriate (i. e., $25). Invertebrate species are presented in four sections. The sections on Life History, and Diet were derived from the literature. The section on Abundance and Distribution consists of data from otter-trawl collections. In addition, comparisons with other studies are included here following our results. The section on Length-frequency Distributions consists of length measurements from all collections, except 1984-1985 when no measurements were taken. Length-frequency distributions were used, when possible, to estimate life stage captured, spawning times, recruitment into Florida Bay for those species which spawn outside the Bay, and growth. Additional material from the literature was added when appropriate. (PDF contains 39 pages)

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The Northeast Fisheries Science Center of NOAA's National Marine Fisheries Service has a long history of research on benthic invertebrates and habitats in support of the management of living marine resources. These studies began in the 1870's under Spencer F. Baird's guidance as part of an effort to characterize the Nation's fisheries and living marine resources and their ecological interactions. This century and a quarter of research has included many benthic invertebrate studies, including community characterizations, shellfish biology and culture, pathology, ecosystem energy budget modeling, habitat evaluations, assessments of human impacts, toxic chemical bioaccumulation in demersal food webs, habitat or endangered species management, benthic autecology, systematics (to define new species and species population boundaries), and other benthic studies. Here we review the scope of past and current studies as a background for strategic research planning and suggest areas for further research to support NOAA's goals of sustainable fisheries management, healthy coastal ecosystems, and protected species populations.

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Dehram group includes Faraghan, Dalan and Kangan formations. Kangan formation ages lower terias. That is one of the important reservoir rocks of southern Iran and Persian Gulf. In this research Kangan formation is studied in two A and B wells. Based on 75 studies on thin section, four carbonate litho acies association A, B, C, D with 12 subfacies are identified. A lithofacies association includes 4 subfacies: A1, A2, A3 and A4. B lithofacies association consists of 3 subfacies: B1, B2 and B3. C lithofacies association consists of 3 subfacies: C1, C2, C3 and D lithofacies association includes 2 subfacies: D1 and D2. On the base of studies lithofacies association of Kangan formations are formed in 3 environments of: Tidal Flat, Lagoon and Barrier Shore Complex in a Carbonated Platform Ramp type. Diagenetic processes have effected this formation. The most important Diagenetic processes are: Cementation, Anhydritization, Micrization, Neomorphism, Bioturbation, Dissolution, Compaction, Dolomitization and Porosity. Sequence staratigraphy studies were performed base on the vertical and horizontal relationship of lithofacies association and well logging in gamma ray and sonic type that causes the identification of two sedimentary sequences: First sedimentary sequence includes: Transgressive System Tract (TST) and High Stand System Tract (HST). The lower boundary of this sequence is in Sequence Boundary 1 (SB1) which shows unconformities of Dalan and Kangan that are Permian-terias unconformities. The upper boundary is in Sequence Boundary 2 (SB2) type that is identified by carbonate facies associated by anhydrite nodular. Second sedimentary sequence includes: TST and HST. Lower and upper boundaries of these sequences are both in SB2 type. The lower and upper boundary is made of carbonate facies with anhydrite nodular.

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The paper presents: 1) biologic summaries for each of the formations for which paleontologic data are available, with brief discussions of the geologic age; 2) geologic correlations of the formations and the distribution of their age-equivalents in Central America, the West Indies, and the southeastern United States; 3) an outline of the paleogeography of middle America. The biologic summaries are based on the paleontologic memoirs in this vol. by Messars. Howe, Berry, Chuchman, Jackson, Canu and Bassler and Pilsbry, Miss Rathbun and myself.

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(PDF contains 15 pages)

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Over 100 molluscan species are landed in Mexico. About 30% are harvested on the Pacific coast and 70% on the Atlantic coast. Clams, scallops, and squid predominate on the Pacific coast (abalone, limpets, and mussels are landed there exclusively). Conchs and oysters predominate on the Atlantic coast. In 1988, some 95,000 metric tons (t) of mollusks were landed, with a value of $33 million. Mollusks were used extensively in prehispanic Mexico as food, tools, and jewelry. Their use as food and jewelry continues. Except in the States of Baja California and Baja California Sur, where abalone, clams, and scallops provide fishermen with year-round employment, mollusk fishing is done part time. On both the Pacific and Atlantic coasts, many fishermen are nomads, harvesting mollusks wherever they find abundant stocks. Upon finding such beds, they build camps, begin harvesting, and continue until the mollusks become so scarce that it no longer pays to continue. They then look for productive beds in other areas and rebuild their camps. Fishermen harvest abalones, mussels, scallops, and clams by free-diving and using scuba and hooka. Landings of clams and cockles have been growing, and 22,000 t were landed in 1988. Fishermen harvest intertidal clams by hand at wading depths, finding them with their feet. In waters up to 5 m, they harvest them by free-diving. In deeper water, they use scuba and hooka. Many species of gastropods have commercial importance on both coasts. All species with a large detachable muscle are sold as scallops. On the Pacific coast, hatchery culture of oysters prevails. Oyster culture in Atlantic coast lagoons began in the 1950's, when beds were enhanced by spreading shells as cultch for spat. (PDF file contains 228 pages.)

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This three-volume monograph represents the first major attempt in over a century to provide, on regional bases, broad surveys of the history, present condition, and future of the important shellfisheries of North and Central America and Europe. It was about 100 years ago that Ernest Ingersoll wrote extensively about several molluscan fisheries of North America (1881, 1887) and about 100 years ago that Bashford Dean wrote comprehensively about methods of oyster culture in Europe (1893). Since those were published, several reports, books, and pamphlets have been written about the biology and management of individual species or groups ofclosely related mollusk species (Galtsoff, 1964; Korringa, 1976 a, b, c; Lutz, 1980; Manzi and Castagna, 1989; Shumway, 1991). However, nothing has been written during the past century that is comparable to the approach used by Ingersoll in describing the molluscan fisheries as they existed in his day in North America or, for that matter, in Europe. (PDF file contains 224 pages.)

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This study aims to reconstruct the history of shore whaling in the southeastern United States, emphasizing statistics on the catch of right whales, Eubalaena glacialis, the preferred targets. The earliest record of whaling in North Carolina is of a proposed voyage from New York in 1667. Early settlers on the Outer Banks utilized whale strandings by trying out the blubber of carcasses that came ashore, and some whale oil was exported from the 1660s onward. New England whalemen whaled along the North Carolina coast during the 1720s, and possibly earlier. As some of the whalemen from the northern colonies moved to Nortb Carolina, a shore-based whale fishery developed. This activity apparently continued without interruption until the War of Independence in 1776, and continued or was reestablished after the war. The methods and techniques of the North Carolina shore whalers changed slowly: as late as the 1890s they used a drogue at the end of the harpoon line and refrained from staying fast to the harpooned whale, they seldom employed harpoon guns, and then only during the waning years of the fishery. The whaling season extended from late December to May, most successfully between February and May. Whalers believed they were intercepting whales migrating north along the coast. Although some whaling occurred as far north as Cape Hatteras, it centered on the outer coasts of Core, Shackleford, and Bogue banks, particularly near Cape Lookout. The capture of whales other than right whales was a rare event. The number of boat crews probably remained fairly stable during much of the 19th century, with some increase in effort in the late 1870s and early 1880s when numbers of boat crews reached 12 to 18. Then by the late 1880s and 1890s only about 6 crews were active. North Carolina whaling had become desultory by the early 1900s, and ended completely in 1917. Judging by export and tax records, some ocean-going vessels made good catches off this coast in about 1715-30, including an estimated 13 whales in 1719, 15 in one year during the early 1720s, 5-6 in a three-year period of the mid to late 1720s, 8 by one ship's crew in 1727, 17 by one group of whalers in 1728-29, and 8-9 by two boats working from Ocracoke prior to 1730. It is impossible to know how representative these fragmentary records are for the period as a whole. The Carolina coast declined in importance as a cruising ground for pelagic whalers by the 1740s or 1750s. Thereafter, shore whaling probably accounted for most of the (poorly documented) catch. Lifetime catches by individual whalemen on Shackleford Banks suggest that the average annual catch was at least one to two whales during 1830·80, perhaps about four during the late 1870s and early 1880s, and declining to about one by the late 1880s. Data are insufficient to estimate the hunting loss rate in the Outer Banks whale fishery. North Carolina is the only state south of New Jersey known to have had a long and well established shore whaling industry. Some whaling took place in Chesapeake Bay and along the coast of Virginia during the late 17th and early 18th centuries, but it is poorly documented. Most of the rigbt whales taken off South Carolina, Georgia, and northern Florida during the 19th century were killed by pelagic whalers. Florida is the only southeastern state with evidence of an aboriginal (pre-contact) whale fishery. Right whale calves may have been among the aboriginal whalers' principal targets. (PDF file contains 34 pages.)

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Adult steelhead (Oncorhynchus mykiss irideus) scales were analyzed from eight fall-run, two spring-run, and one winter-run stocks within the Klamath-Trinity River system, from 1981 through 1983, to provide basic information on age, growth, and life history. The higher degree of half-pounder occurrence of upper Klamath River steelhead stocks (86.7 to 100%) compared to Trinity River steelhead stocks (32.0 to 80.0%) was the major life history difference noted in scale analysis. Early life history was similar for all areas sampled with most juveniles (86.4%) remaining in freshwater during the first two years of life before migrating to sea. Repeat spawning ranged from 17.6 to 47.9% for fall-run, 40.0 to 63.6% for spring-run, and 31.1% for winter-run steelhead. Mean length of adults at first spawning was inversely related to percent half-pounder occurrence in each stock. Ages of returning spawners, back calculated lengths at various life stages, and growth information are presented. (PDF contains 22 pages)

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Elkhorn Slough was first exposed to direct tidal forcing from the waters of Monterey Bay with the construction of Moss Landing Harbor in 1946. Elkhorn Slough is located mid-way between Santa Cruz and Monterey close to the head of Monterey Submarine Canyon. It follows a 10 km circuitous path inland from its entrance at Moss Landing Harbor. Today, Elkhorn Slough is a habitat and sanctuary for a wide variety of marine mammals, fish, and seabirds. The Slough also serves as a sink and pathway for various nutrients and pollutants. These attributes are directly or indirectly affected by its circulation and physical properties. Currents, tides and physical properties of Elkhorn Slough have been observed on an irregular basis since 1970. Based on these observations, the physical characteristics of Elkhorn Slough are examined and summarized. Elkhorn Slough is an ebb-dominated estuary and, as a result, the rise and fall of the tides is asymmetric. The fact that lower low water always follows higher high water and the tidal asymmetry produces ebb currents that are stronger than flooding currents. The presence of extensive mud flats and Salicornia marsh contribute to tidal distortion. Tidal distortion also produces several shallow water constituents including the M3, M4, and M6 overtides and the 2MK3 and MK3 compound tides. Tidal elevations and currents are approximately in quadrature; thus, the tides in Elkhorn Slough have some of the characters of a standing wave system. The temperature and salinity of lower Elkhorn Slough waters reflect, to a large extent, the influence of Monterey Bay waters, whereas the temperature and salinity of the waters of the upper Slough (>5 km from the mouth) are more sensitive to local processes. During the summer, temperature and salinity are higher in the upper slough due to local heating and evaporation. Maximum tidal currents in Elkhorn Slough have increased from approximately 75 to 120 cm/s over the past 30 years. This increase in current speed is primarily due to the change in tidal prism which has increased from approximately 2.5 to 6.2 x 106 m3 between 1956 and 1993. The increase in tidal prism is the result of both 3 rapid man-made changes to the Slough, and the continuing process of tidal erosion. Because of the increase in the tidal prism, the currents in Elkhorn Slough exhibit positive feedback, a process with uncertain consequences. [PDF contains 55 pages]

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A review article looking at the type of information requirements commonly shared by scientists and their use of traditional information services. Areas covered include primary requirements of IFE (Institute of Freshwater Ecology) staff, pure versus applied research, informal and personal sources of information, and traditional library and information services. It goes on to describe how research into information systems and technology may improve the wider accessibility and use of information to the scientific community. Technologies covered include online databases, telecommunications, gateways, expert systems, optical technology and applications of CDROM.

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Citharichthys cornutus and C. gymnorhinus, diminutive flatfishes inhabiting continental shelves in the western Atlantic Ocean, are infrequently reported and poorly known. We identified 594 C. cornutus in 56 different field collections (68–287 m; most between 101–200 m) off the eastern United States, Bahamas, and eastern Caribbean Sea. Historical records and recently captured specimens document the northern geographic range of adults on the shelf off New Jersey (40°N, 70°W). Citharichthys cornutus measured 17.2–81.3 mm standard length (SL); males (20.0–79.1 mm SL) and females (28.0–81.3 mm SL) attain similar sizes (sex could not be determined for fish <20 mm SL). Males reach nearly 100% maturity at ≥60 mm SL. The smallest mature females are 41.5 mm SL, and by 55.1 mm SL virtually all are mature. Juveniles are found with adults on the outer shelf. Only 214 C. gymnorhinus were located in 42 different field collections (35–201 m, with 90% between 61 and 120 m) off the east coast of the United States, Bahamas, and eastern Caribbean Sea. Adults are found as far north as the shelf off Cape Hatteras, NC (35°N, 75°W). This diminutive species (to 52.4 mm SL) is among the smallest flatfishes but males (n=131; 20.3–52.4 mm SL) attain a slightly larger maximum size than that of females (n=58; 26.2–48.0 mm SL). Males begin to mature between 29 and 35 mm SL and reach 100% maturity by 35–40 mm SL. Some females are mature at 29 mm SL, and all females >35.1 mm SL are mature. Overlooked specimens in museum collections and literature enabled us to correct long-standing inaccuracies in northern distributional limits that appear in contemporary literature and electronic data bases for these species. Associated locality-data for these specimens allow for proper evaluation of distributional information for these species in relation to hypotheses regarding shifts in species ranges due to climate change effects.