The human infl uence on marine ecosystems is being recognized as a basis for extending the horizons of management. Historical anthropogenic infl uence has involved a wide variety of factors, including the effects of fi shing on the dynamics of individual resource species. More inclusive complexity includes the interactions among species, and their interactions with other aspects of their biotic and physical environment. In this chapter, we review these elements of complexity for the central Baltic Sea. This ecosystem has a long history of human infl uence and its own special characteristics, due to its geographic location, geomorphic traits, and socio-political context. More and more of the complexity of this ecosystem is being recognized as scientists add to the wealth of documentation regarding the infl uence of surrounding terrestrial activities, monitor the dynamics of component populations, establish the effects of weather and climate, and illuminate the relationships among the various elements of the ecosystem. There is a great deal of historical information to characterize the changes that have occurred, not only among the various species making up the ecosystem, but also at the ecosystem level. Some of these have involved regime shifts, in part owing to climatic factors. Such significant changes involve more than one of the ecosystem’s trophic levels as well as physical features such as salinity, temperature, and oxygen concentration. We begin to understand some of the complexity of ecosystems when we recognize that such factors are not alone, however, and realize that trophic cascade dynamics and feedback loops are also involved. Of particular importance for fi sheries management is the clarity with which we have observed, documented, and explained some of the effects of fi shing, not simply as an infl uence on individual resource species, but on the ecosystem as a whole. Some of these ecological aspects are currently used in fi sh stock assessment and management in the central Baltic Sea, but recently acquired additional knowledge could be potentially used in the future to reach the goal of a sustainable exploitation of fi sheries resources in this area.
Food-web and climate-related dynamics in the Baltic Sea: present and potential future applications in fish stock assessment and management
Casini M
;
2011
Abstract
The human infl uence on marine ecosystems is being recognized as a basis for extending the horizons of management. Historical anthropogenic infl uence has involved a wide variety of factors, including the effects of fi shing on the dynamics of individual resource species. More inclusive complexity includes the interactions among species, and their interactions with other aspects of their biotic and physical environment. In this chapter, we review these elements of complexity for the central Baltic Sea. This ecosystem has a long history of human infl uence and its own special characteristics, due to its geographic location, geomorphic traits, and socio-political context. More and more of the complexity of this ecosystem is being recognized as scientists add to the wealth of documentation regarding the infl uence of surrounding terrestrial activities, monitor the dynamics of component populations, establish the effects of weather and climate, and illuminate the relationships among the various elements of the ecosystem. There is a great deal of historical information to characterize the changes that have occurred, not only among the various species making up the ecosystem, but also at the ecosystem level. Some of these have involved regime shifts, in part owing to climatic factors. Such significant changes involve more than one of the ecosystem’s trophic levels as well as physical features such as salinity, temperature, and oxygen concentration. We begin to understand some of the complexity of ecosystems when we recognize that such factors are not alone, however, and realize that trophic cascade dynamics and feedback loops are also involved. Of particular importance for fi sheries management is the clarity with which we have observed, documented, and explained some of the effects of fi shing, not simply as an infl uence on individual resource species, but on the ecosystem as a whole. Some of these ecological aspects are currently used in fi sh stock assessment and management in the central Baltic Sea, but recently acquired additional knowledge could be potentially used in the future to reach the goal of a sustainable exploitation of fi sheries resources in this area.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
