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71.
Coordinating decisions and actions among interacting sectors is a critical component of ecosystem-based management, but uncertainty about coordinated management's effects is compromising its perceived value and use. We constructed an analytical framework for explicitly calculating how coordination affects management decisions, ecosystem state and the provision of ecosystem services in relation to ecosystem dynamics and socio-economic objectives. The central insight is that the appropriate comparison strategy to optimal coordinated management is optimal uncoordinated management, which can be identified at the game theoretic Nash equilibrium. Using this insight we can calculate coordination's effects in relation to uncoordinated management and other reference scenarios. To illustrate how this framework can help identify ecosystem and socio-economic conditions under which coordination is most influential and valuable, we applied it to a heuristic case study and a simulation model for the California Current Marine Ecosystem. Results indicate that coordinated management can more than double an ecosystem's societal value, especially when sectors can effectively manipulate resources that interact strongly. However, societal gains from coordination will need to be reconciled with observations that it also leads to strategic simplification of the ecological food web, and generates both positive and negative impacts on individual sectors and non-target species. 相似文献
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Recent large-scale wildfires have increased populations of wood-boring insects in the Black Hills of South Dakota. Because little is known about possible impacts of wood-boring insects in the Black Hills, land managers are interested in developing monitoring techniques such as flight trapping with semiochemical baits. Two trap designs and four semiochemical attractants were tested in a recently burned ponderosa pine, Pinus ponderosa Dougl. ex Laws., forest in the Black Hills. Modified panel and funnel traps were tested in combination with the attractants, which included a woodborer standard (ethanol and alpha-pinene), standard plus 3-carene, standard plus ipsenol, and standard plus ipsdienol. We found that funnel traps were equally efficient or more efficient in capturing wood-boring insects than modified panel traps. Trap catches of cerambycids increased when we added the Ips spp. pheromone components (ipsenol or ipsdienol) or the host monoterpene (3-carene) to the woodborer standard. During the summers of 2003 and 2004, 18 cerambycid, 14 buprestid, and five siricid species were collected. One species of cerambycid, Monochamus clamator (LeConte), composed 49 and 40% of the 2003 and 2004 trap catches, respectively. Two other cerambycids, Acanthocinus obliquus (LeConte) and Acmaeops proteus (Kirby), also were frequently collected. Flight trap data indicated that some species were present throughout the summer, whereas others were caught only at the beginning or end of the summer. 相似文献
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A N Baer P B Costello F A Green 《Biochemical and biophysical research communications》1990,169(2):332-338
Incubation of rat basophilic leukemia cells with exogenous arachidonic acid and permeabilizing concentrations of ethanol resulted in the production of 5-, 12-, and 15-hydroxyeicosatetraenoic acids. With chiral phase high performance liquid chromatography, it was demonstrated that the 5-hydroxyeicosatetraenoic acid had strict (S) stereospecificity while contrary to expectation, the 12- and the 15-hydroxyeicosatetraenoic acids were non-racemic mixtures of the stereoisomers with the S/R ratios averaging 8.6 and 2.2, respectively. If the strict (S) stereospecificity of mammalian lipoxygenases holds true, these results suggest that the 15- and 12-hydroxyeicosatetraenoic acids may be derived from non-lipoxygenase sources. Examination of the chirality of the oxygenase products of unsaturated fatty acids may be of value in defining the enzymes which are activated in vivo in pathological states. 相似文献
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