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821.
Elizabeth R Selig Oren Ahoobim Freddy Arocha Annabelle Cruz‐Trinidad Rod Fujita Mafaniso Hara Laure Katz Patrick McConney Blake D Ratner Lina M Saavedra‐Díaz Anne‐Maree Schwarz Djiga Thiao Elin Torell Sebastian Troëng Sebastian Villasante 《Fish and Fisheries》2017,18(3):543-570
Fisheries provide nutrition and livelihoods for coastal populations, but many fisheries are fully or over‐exploited and we lack an approach for analysing which factors affect management tool performance. We conducted a literature review of 390 studies to assess how fisheries characteristics affected management tool performance across both small‐scale and large‐scale fisheries. We defined success as increased or maintained abundance or biomass, reductions in fishing mortality or improvements in population status. Because the literature only covered a narrow set of biological factors, we also conducted an expert elicitation to create a typology of broader fishery characteristics, enabling conditions and design considerations that affect performance. The literature suggested that the most commonly used management tool in a region was often the most successful, although the scale of success varied. Management tools were more often deemed successful when used in combination, particularly pairings of tools that controlled fishing mortality or effort with spatial management. Examples of successful combinations were the use of catch limits with quotas and limited entry, and marine protected areas with effort restrictions. The most common factors associated with inadequate biological performance were ‘structural’ issues, including poor design or implementation. The expert‐derived typologies revealed strong local leadership, high community involvement and governance capacity as common factors of success across management tool categories (i.e. input, output and technical measures), but the degree of importance varied. Our results are designed to inform selection of appropriate management tools based on empirical data and experience to increase the likelihood of successful fisheries management. 相似文献
822.
Heavy metal content in Aporrectodea caliginosa (Oligochaeta, Lumbricidae) in the city of Kiel (Germany, Schleswig-Holstein) In November 1995 the content of lead, cadmium, copper and zinc in earthworms of the Aporrectodea caliginosa species was investigated at 28 sites of the Kiel area, as well as at one reference site (Belauer See, ca. 20 kilometres south of Kiel), and compared with the heavy metal content in the soil taken from all those sites. As for the lead and copper content, a positive correlation could be established between the earthworms and the soil. However, the lead content in the earthworms did not depend only on its amount in the soil, but also on soil pH and calcium content. Their copper content decreased exponentially as weight increased. The content of lead, cadmium and copper in A. caliginosa suggested an influence of urban soil pollution on the heavy metal content in earthworms. According to the grouping of heavy metal content in the earthworms, which was done in the course of the research work, the city of Kiel ranges among a minor to a medium degree of pollution caused by the investigated heavy metals. 相似文献
823.
Felix Spindler Benoit Pugin Hanspeter Buser Hans-Peter Jalett Ulrich Pittelkow Hans-Ulrich Blaser 《Pest management science》1998,54(3):302-304
The application of enantioselective catalytic methods for the technical preparation of chiral agrochemicals is illustrated for three active ingredients of the acylanilide type. The key step for the technical synthesis of the herbicide (S)-metolachlor is the enantioselective hydrogenation of an imine intermediate using a novel iridium ferrocenyldiphosphine catalyst with an unprecedented high activity and 80% ee. (R)-metalaxyl and (αS,3R)-clozylacon were synthesized via the enantioselective hydrogenation of corre-sponding enamide precursors with Rh and Ru/binap catalysts with >95% and 99% enantiomeric purity, respectively. © 1998 Society of Chemical Industry 相似文献