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71.
72.
Globally, fisheries are challenged by the combined impacts of overfishing, degradation of ecosystems and impacts of climate change, while fisheries livelihoods are further pressured by conservation policy imperatives. Fishers' adaptive responses to these pressures, such as exiting from a fishery to pursue alternative livelihoods, determine their own vulnerability, as well as the potential for reducing fishing effort and sustaining fisheries. The willingness and ability to make particular adaptations in response to change, such as exiting from a declining fishery, is influenced by economic, cultural and institutional factors operating at scales from individual fishers to national economies. Previous studies of exit from fisheries at single or few sites, offer limited insight into the relative importance of individual and larger-scale social and economic factors. We asked 599 fishers how they would respond to hypothetical scenarios of catch declines in 28 sites in five western Indian Ocean countries. We investigated how socioeconomic variables at the individual-, household- and site-scale affected whether they would exit fisheries. Site-level factors had the greatest influence on readiness to exit, but these relationships were contrary to common predictions. Specifically, higher levels of infrastructure development and economic vitality - expected to promote exit from fisheries - were associated with less readiness to exit. This may be due to site level histories of exit from fisheries, greater specialisation of fishing households, or higher rewards from fishing in more economically developed sites due to technology, market access, catch value and government subsidies. At the individual and household scale, fishers from households with more livelihood activities, and fishers with lower catch value were more willing to exit. These results demonstrate empirically how adaptive responses to change are influenced by factors at multiple scales, and highlight the importance of understanding natural resource-based livelihoods in the context of the wider economy and society. 相似文献
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77.
Benthic cover, current strengths, and fish abundance and diversity were examined on 150 lagoonal patch reefs and mapped to
determine their distribution, inter-relationships, and relationship to the fisheries closure in Glovers Reef Atoll. Current
strength was highest at both the northern and southern ends of the atoll and largely controlled by local wind and weakly by
tidal forcing. Benthic functional group distributions varied throughout the atoll and had distinct areas of dominance. In
contrast, dominance of coral species was weaker, reflecting the lost cover and zonation of Acropora, Porites, and Montastraea that were reported in the 1970s. Hard and soft corals dominated the windward rim, while the central and leeward lagoon had
lower current strengths and sea grass and fleshy green algae were relatively more abundant. Brown erect algae were relatively
more common in the north and calcifying green and red algae the southern ends of the atoll. Only Montastraea-Agaricia agaricites distributions were similar to reports from the 1970s with high relative dominance in the southern and northeast atoll. The
central-northern zone, which was described as an Acropora zone in the 1970s, was not recognizable, and Porites porites, P. astreoides, Millepora alcicornis, and Favia fragum were the most abundant species during this survey. Hard and soft coral cover abundance declined away from the reef rim and tidal channels and was associated with fast seawater
turnover and high surgeonfish abundance. Consequently, the windward rim area has retained the most original and persistent
hard-soft coral and surgeonfish community and is considered a priority for future management, if the goal is to protect coral
from fishing impacts. 相似文献
78.
Marine protected areas (MPAs) have been widely adopted as the leading tool for coral-reef conservation, but resource users seldom accept them , and many have failed to produce tangible conservation benefits [3]. Few studies have objectively and simultaneously examined the types of MPAs that are most effective in conserving reef resources and the socioeconomic factors responsible for effective conservation [4-6]. We simultaneously explored measures of reef and socioeconomic conservation success at four national parks, four comanaged reserves, and three traditionally managed areas in Indonesia and Papua New Guinea. Underwater visual censuses of key ecological indicators [7, 8] revealed that the average size and biomass of fishes were higher in all areas under traditional management and at one comanaged reserve when compared to nearby unmanaged areas. Socioeconomic assessments [6, 9, 10] revealed that this "effective conservation" was positively related to compliance, visibility of the reserve, and length of time the management had been in place but negatively related to market integration, wealth, and village population size. We suggest that in cases where the resources for enforcement are lacking, management regimes that are designed to meet community goals can achieve greater compliance and subsequent conservation success than regimes designed primarily for biodiversity conservation. 相似文献
79.
Chad A. Van Huis Agustin Casimiro-Garcia Christopher F. Bigge Wayne L. Cody Danette A. Dudley Kevin J. Filipski Ronald J. Heemstra Jeffrey T. Kohrt Robert J. Leadley Lakshmi S. Narasimhan Thomas McClanahan Igor Mochalkin Michael Pamment J. Thomas Peterson Vaishali Sahasrabudhe Robert P. Schaum Jeremy J. Edmunds 《Bioorganic & medicinal chemistry》2009,17(6):2501-2511
Aiming to improve upon previously disclosed Factor Xa inhibitors, a series of 4,4-disubstituted pyrrolidine-1,2-dicarboxamides were explored with the intent of increasing the projected human half-life versus 5 (projected human t1/2 = 6 h). A stereospecific route to compounds containing a 4-aryl-4-hydroxypyrrolidine scaffold was developed, resulting in several compounds that demonstrated an increase in the half-life as well as an increase in the in vitro potency compared to 5. Reported herein is the discovery of 26, containing a (2R,4S)-4-hydroxy-4-(2,4-difluorophenyl)-pyrrolidine scaffold, which is a selective, orally bioavailable, efficacious Factor Xa inhibitor that appears suitable for a once-daily dosing (projected human t1/2 = 23 h). 相似文献
80.
Iannis E Adamopoulos Cheng-chi Chao Richard Geissler Drake Laface Wendy Blumenschein Yoichiro Iwakura Terrill McClanahan Edward P Bowman 《Arthritis research & therapy》2010,12(1):R29