Suitable sites for sustainable aquaculture development in Mymensingh, Bangladesh: A GIS methodological perspective

A GIS study was carried out to find out the sites suitable for aquaculture in Mymensingh region. A number of criteria were selected for GIS modeling followed by the approach of Kapetsky (1994). The criteria were developed from a range of existing data sources such as, surface and underground water level, availability of feed ingredients and animal wastes, sources of fish fry, market facilities, extension support and communication facilities for aquaculture development. The data were located, collected and compiled from different GOs and NGOs located in the region along with primary data from the field survey wherever necessary and then prepared for computer analyses. Using the database, a series of GIS models were developed in order to ascertain and prioritize the most suitable areas for aquaculture development in the region. Out of total 407,528 ha available lands in the region, the study identified 99,415 ha very suitable and 302,754 ha moderately suitable for aquaculture promotion. Result of the study is indicative to the modeling power of GIS for aquaculture application and could be used to refine the models in future, particularly if it is supported with further detail field data. To get a more concrete and complete model, detailed study should be made available on the availability of mustard oil cake, rice bran, wheat bran, and usable animal and urban wastes that could be used as low-cost feed for sustainable aquaculture.

Prediction, Chaos and Ecological Perspective.

As defined, the modeling procedure is quite broad. For example, the chosen compartments may contain a single organism, a population of organisms, or an ensemble of populations. A population compartment, in turn, could be homogeneous or possess structure in size or age. Likewise, the mathematical statements may be deterministic or probabilistic in nature, linear or nonlinear, autonomous or able to possess memory. Examples of all types appear in the literature. In practice, however, ecosystem modelers have focused upon particular types of model constructions. Most analyses seem to treat compartments which are nonsegregated (populations or trophic levels) and homogeneous. The accompanying mathematics is, for the most part, deterministic and autonomous. Despite the enormous effort which has gone into such ecosystem modeling, there remains a paucity of models which meets the rigorous &! validation criteria which might be applied to a model of a mechanical system. Most ecosystem models are short on prediction ability. Even some classical examples, such as the Lotka-Volterra predator-prey scheme, have not spawned validated examples.

Coastal erosion as a natural resource management problem: An economic perspective

Unremitting waves and occasional storms bring dynamic forces to bear on the coast. Sediment flux results in various patterns of erosion and accretion, with an overwhelming majority (80 to 90 percent) of coastline in the eastern U.S. exhibiting net erosion in recent decades. Climate change threatens to increase the intensity of storms and raise sea level 18 to 59 centimeters over the next century. Following a lengthy tradition of economic models for natural resource management, this paper provides a dynamic optimization model for managing coastal erosion and explores the types of data necessary to employ the model for normative policy analysis. The model conceptualizes benefits of beach and dune sediments as service flows accruing to nearby residential property owners, local businesses, recreational beach users, and perhaps others. Benefits can also include improvements in habitat for beach- and dune-dependent plant and animal species. The costs of maintaining beach sediment in the presence of coastal erosion include expenditures on dredging, pumping, and placing sand on the beach to maintain width and height. Other costs can include negative impacts on the nearshore environment. Employing these constructs, an optimal control model is specified that provides a framework for identifying the conditions under which beach replenishment enhances economic welfare and an optimal schedule for replenishment can be derived under a constant sea level and erosion rate (short term) as well as an increasing sea level and erosion rate (long term). Under some simplifying assumptions, the conceptual framework can examine the time horizon of management responses under sea level rise, identifying the timing of shift to passive management (shoreline retreat) and exploring factors that influence this potential shift. (PDF contains 4 pages)

Poverty alleviation and rural development in Nigeria: a gender perspective

The paper examines the concept of the feminization of poverty and reviews the limited evidence on the extent of poverty among women. It then examines the arguments that poor women can be highly effective change agents for the eradication of poverty. However, all the women may be considered as instruments for eliminating poverty, lack of understanding an appreciation of the impact of their sex roles and of gender roles and stereotypes continue to prevent the realization of this potential. Therefore, the paper moves on to summarize the differences between sex and gender and examines how both women's sexes roles and the imp gender roles and stereotypes lead to the feminization of poverty and exclude women from the participation in development and programmes to eliminate poverty. The paper reviews the major approaches: women in development or WID, gender and development or GAD and extension of GAD known as mainstreaming. Finally, it considers the issue of poverty, women and gender in Nigeria. It also advances a number of recommendations on women and gender poverty and rural development for the consideration of policy-makers in Nigeria

Toxic blue-green algae: The "problem" in perspective

The incidence of blue-green algal blooms and surface scum-formation are certainly not new phenomena. Many British and European authors have been faithfully describing the unmistakable symptoms of blue-green algal scums for over 800 years. There is no disputing that blue-green algal toxins are extremely harmful. Three quite separate categories of compound have been separated: neurotoxins; hepatotoxins and lipopolysaccharides. There is a popular association between blue-green algae and eutrophication. Certainly the main nuisance species - of Microcystis, Anabaena and Aphanizomenon are rare in oligotrophic lakes and reservoirs. Several approaches have been proposed for the control of blue-green algae. Distinction is made between methods for discharging algae already present (eg algicides; straw bales; viruses; parasitic fungi and herbivorous ciliates), and methods for averting an anticipated abundance in the future (phosphorous control, artificial circulation etc).

A review of current biological and recent environmental research on Lake Baikal from a British perspective

In 1990, "BICER" or the Baikal International Centre for Ecological Research was created to foster collaborative research on Lake Baikal. The British effort in BICER was initiated and is administered by the Royal Society, London. Much of the on-going research effort is now focussed on environmental change, as there is increasing concern about recent changes in the lake's unique ecosystem that could be linked with the effects of water pollution from catchment effluents. Monitoring studies of the phytoplankton in Lake Baikal's southern basin indicate that several species have increased in abundance since the mid-70's. Diatoms in Lake Baikal sediments are also being studied.

The role of specially designated wildlife sites in freshwater conservation - an English perspective

The value of specially designated sites in conserving biodiversity has been a hotly debated issue for many years. The debate has recently been given fresh impetus by the creation of Natural England, the new Government Agency responsible for the protection and enhancement of the natural environment in England, and the challenges facing the management of designated sites resulting from the increasingly tangible effects of climate change. In the freshwater environment, the role of designated sites is very much under the spotlight because of the implementation of the European 'Water Framework' Directive, which aspires to holistic, ecologically-based management of aquatic habitats.This paper explores the underlying premises of, and rationale for, special site designations for wildlife, and provides a frank account of the inevitable clash of management philosophies that designated sites create in the freshwater environment, drawing on experiences of managing designated freshwater sites in England over the past decade. A positive role is outlined for designated sites in freshwater conservation, which addresses these management conflicts in a way that not only meets Government obligations towards these sites but also paves the way for enlightened, progressive management of the wider freshwater resource. As part of this account, attempts are made to clarify the relationship between key biodiversity-related policy drivers in the freshwater environment, and to explain how the spectre of climate change can be addressed within designated site management. The importance of strategic freshwater science, collaboratively designed and funded, in maximising the value of the designated freshwater site network to the wider freshwater habitat resource, is stressed.

Collaborative training program in coastal management in the Philippines: a local initiative with a global perspective

A collaborative project in developing a broad-based coastal management training program in the Philippines is being undertaken by a group of government and nongovernment agencies. It addresses the lack of expertise in planning an implementation for coastal management in the country. The process will be documented to serve as a guide in starting and maintaining the process of collaborative training in coastal management in the region. Other training initiatives are outlined including regional and global efforts.

A personal perspective on literature searches in remote areas

The article is focused on the author's personal perspective on literature searches in remote areas. Topics covered are: literature searching; collection of key articles; catalog local fisheries library holdings; budgets; documentation of research results; and the author's thought for the future.

Charter and Party Boat Operators in the U.S. Gulf of Mexico: A Social Structure Perspective

To better address the charter and party boat fishery needs in the U.S. Gulf of Mexico, fishery managers must understand the linkages between the industry and other groups and organizations that affect its success. Gulf state charter and party boat operators were interviewed to ascertain the extent of their social network linkages, membership in community organizations, business community relationships, and linkages to information sources. Approximately one-third to one-half of the charter and party boat operators did not belong to local community organizations that could assist their business through tourism promotion or natural resource protection. Despite their limited integration in the community, the vast majority of operators gave and received referrals from other businesses. Of four major information sources, the National Weather Service and the County Marine Extension agents were rated highest and lowest, respectively, in mean importance to charter and party boat operators. Results suggest that business success can be enhanced by strengthening network ties between operators and local businesses, chambers of commerce, and tourism organizations. For this to occur, individual operators and charter/party boat organizations need to become more effective in representing industry interests. Informational linkages between industry and govemment agencies also need improvement.

An Ecological Perspective on Inshore Fisheries in the Main Hawaiian Islands

A description of fisheries within a depth of 100 fathoms is provided for the eight southeastern-most islands of the Hawaiian Archipelago, known as the main Hawaiian Islands (MHI). These are the inhabited islands of the State of Hawaii and are those most subject to inshore fishing pressure, because of their accessibility. Between 1980 and 1990, an average of 1,300 short tons of fishes and invertebrates were reported annually within 100 fm by commercial fishermen. Total landings may be significantly greater, since fishing is a popular pastime of residents and noncommercial landings are not reported. Although limited data are available on noncommercial fisheries, the majority of this review is based on reported commercial landings. The principal ecological factors influencing fisheries in the MHI include coastal currents, the breadth and steepness of the coastal platform, and differences in windward and leeward climate. Expansive coastal development, increased erosion, and sedimentation are among negative human impacts on inshore reef ecosystems on most islands. Commercial fisheries for large pelagics (tunas and billfishes) are important in inshore areas around Ni'ihau, Ka'ula Rock, Kauai, and the Island of Hawaii (the Big Island), as are bottom "handline" fisheries for snappers and groupers around Kauai and Molokai. However, many more inshore fishermen target reef and estuarine species. Two pelagic carangids, "akule," Selar crumenopthalmus, and "opelu," Decapterus macarellus, support the largest inshore fisheries in the MHI. During 1980-90, reported commercial landings within three miles of shore averaged 203 and 125 t for akule and opelu, respectively. Akule landings are distributed fairly evenly throughout the MHI, while more than 72% of the state's inshore opelu landings take place on the Big Island. Besides akule and opelu, other important commercial fisheries on all the MHI include those for surgeon, soldier, parrot, and goatfishes; snappers; octopus, and various trevallies. Trends in reported landings, trips, and catch per unit effort over the last decade are outlined for these fisheries. In heavily populated areas, fishing pressure appears to exceed the capacity of inshore resources to renew themselves. Management measures are beginning to focus on methods of limiting inshore fishing effort, while trying to maintain residents' access to fishing.

Coastal States and Distant-water Fishing Nation Relations: An Economist's Perspective

The widespread implementation of Extended Fisheries Jurisdiction (EFJ) has confronted coastal states with several resource management problems. One of these consists of the economic relations, if any, that the coastal state should establish with distant-water fishing nations (DWFN's) seeking access to the coastal state's 200-mile zone. Several of the other papers presented here deal with specific aspects of the issue. This paper, on the other hand, will concern itself with the question of the analytical framework to be used by economists in studying this issue. It will offer some suggestions with respect to possible components of the framework. In doing so, the paper will restrict itself to the coastal state's perspective of EFJ and the management issues arising therefrom. It goes without saying, of course, that an enlightened coastal state will attempt to acquaint itself with the DWFN view of the world.

A U.S. Perspective on Access to Fisheries Resources

The passage of the Magnuson Fishery Conservation and Management Act of 1976 (MFCMA) and the establishment of a 200-mile exclusive economic zone (EEZ) in 1983 have resulted in a radical change in the pattern of foreign fishing operations off the U. S. coasts. Likewise, the extensions of 200-mile EEZ's by other nations have impacted U.S. distant-water fisheries. The result has been that a new international framework for fisheries is emerging and is continuing to evolve.