Suchergebnisse

In the past ten years, China has developed to be one of the most important countries of fishery production field. Annually Chinese fishery products is increasing . In 2009 the total fishery production is 50.4 million tones.(China statistical reports,2009) As the same rate as the increase economy, the sharply development of fishery production is also remarkable. But there are serious problems behind the promising surface. The conflicts between the economic development and ecological and environmental declaration are becoming prominent. The most serious situation is in Yangtze River basin. According to a Chinese governmental report, the total annul aquatic production in Yangtze River is about 20% of total national fishery production. But from the latest 20 years, the fishery biomass situation is continue damaging. How to fix Yangtze River ecosystem is the top priority in fishery management. And how to deal with the fishery of Yangtze River is also the main problem of Chinese freshwater industry. Chinese government has authorized many measures and policies in the last 10 years, but the situation became even worse during this period. Because of the historical and political reasons. Chinese academic levels in fishery economics and management is limited, and the fisheries research is not given enough priority. There is hardly any effective research on Yangtze River fishery resources today. At a global level , a new term is becoming quite popular, within the field of fishery management namely ecosystem-based fishery management. Many foreign countries has implemented this theory into practice and also FAO support this theory as the most important management theory in fishery in the future.(FAO, 2005) The same as many other new theories, there are so many disputes and controversies on this theory. Problems often pointed at are shortage of data and poor knowledge, the theory is still not fully developed. Based on the investigation of the formal management failure in China. We figure out that may be the ecosystem-based fishery management can save the environment and fishery resources in Yangtze River. We are going to analysis the main principles, goals and policies for the fishery management, which is the original in Yangtze River academic research. Good theory needs to be tested by facts. Based on the theory of EBFM in Yangtze River, we chose a small island in Yangtze River to implement the theory . According to the local conditions and new development perspective, we chose Jiangxin island of Nanjing as a research field. We gave management advices for this island and hope it can be a good example that balance the environment profit and economic benefit. This paper will be a operation advices give to the development company of Jiangxin island for the implementation of ecosystem based fishery management on that island.

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a legislative requirement, GAO reviewed the: (1) American Fisheries Act's impact on the production of pollock fillets and the price paid for them; and (2) act's positive and negative impacts on fishing operations in the pollock fishery and other fisheries in Alaska."

Discusses marine environment management and maximization of the sustainable use and non‐use values of the flow of goods and services generated by that environment. Expands on the traditional economic model of fishery management to include the protection of non‐use values. Assesses international agreements made to include the protection of non‐use values of the marine environment, and examines the conflict between GATT rules and unilateral attempts to protect existence values. Proposes solutions based on the full cost pricing principle.

AbstractFishery management complexity conspires to defeat seemingly obvious solutions to overfishing. Management may not adequately include decisions of fishers, management, and politicians. A new, simple, but acceptably complex fish population model is meshed with both fishery activities and management decision making. The population component is based on the common single stock biomass dynamic model. Modifications allow biomass feedback on rates of addition to the stock due to growth and to entry of young fish. Delayed and seasonal entry of new fish biomass is possible. A co‐flow structure tracks age of biomass without using cohorts. Fishers enter the fishery only if catch rates are sufficiently high. When catch rates are low fishers improve their efficiency. Excessive fishing damages ecosystem support of the fish population. Managers attempt to maintain fish stocks at acceptable biomass levels, but lobbying by fishers and varying support of politicians limits their efforts. Copyright © 2008 John Wiley & Sons, Ltd.

The development of a fish stock highly depends on changing and often unpredictable environmental conditions. Thus, stochastic stock growth has to be taken into account when determining optimal fishery policies. In my dissertation I examine how the optimal fishery management will be influenced by uncertain environmental conditions. I determine optimal harvesting strategies in a stochastic fishery model in comparison to a deterministic benchmark model as well as under different degrees of risk aversion among fishermen and consumers. In addition I demonstrate how optimal fishery management will change under the concrete environmental uncertainty of evolving ocean acidification. ; Die Entwicklung eines Fischbestandes hängt stark von sich verändernden und häufig unvorhersehbaren Umweltbedingungen ab. Stochastisches Wachstum muss daher bei der Bestimmung einer optimalen Fischereipolitik berücksichtigt werden. In meiner Dissertation untersuche ich den Einfluss der Umweltunsicherheiten auf das optimale Fischereimanagement. Ich vergleiche die optimale Fangstrategie unter Sicherheit und unter Unsicherheit sowie unter Berücksichtigung der Risikoaversion auf Seiten der Fischer und Konsumenten. Ergänzend veranschauliche ich am Bespiel der zunehmenden Ozeanversauerung, wie sich Fischereimanagement bei unsicheren Umweltbedingungen grundlegend ändern kann.