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991.
Marine protected areas are not established in an institutional and governance vacuum and managers should pay attention to the wider social–ecological system in which they are immersed. This article examines Islas Choros-Damas Marine Reserve, a small marine protected area located in a highly productive and biologically diverse coastal marine ecosystem in northern Chile, and the interactions between human, institutional, and ecological dimensions beyond those existing within its boundaries. Through documents analysis, surveys, and interviews, we described marine reserve implementation (governing system) and the social and natural ecosystem-to-be-governed. We analyzed the interactions and the connections between the marine reserve and other spatially explicit conservation and/or management measures existing in the area and influencing management outcomes and governance. A top-down approach with poor stakeholder involvement characterized the implementation process. The marine reserve is highly connected with other spatially explicit measures and with a wider social–ecological system through various ecological processes and socio-economic interactions. Current institutional interactions with positive effects on the management and governance are scarce, although several potential interactions may be developed. For the study area, any management action must recognize interferences from outside conditions and consider some of them (e.g., ecotourism management) as cross-cutting actions for the entire social–ecological system. We consider that institutional interactions and the development of social networks are opportunities to any collective effort aiming to improve governance of Islas Choros-Damas marine reserve. Communication of connections and interactions between marine protected areas and the wider social–ecological system (as described in this study) is proposed as a strategy to improve stakeholder participation in Chilean marine protected areas. 相似文献
992.
Hana Patzenhauerová Josef Bryja Radim Šumbera 《Behavioral ecology and sociobiology》2010,64(5):757-767
The African mole-rats (Bathyergidae, Rodentia) are subterranean rodents that have evolved a wide range of social organisations
varying from solitary to eusocial. Due to some unusual features of their breeding and social systems, much attention has been
focused on social species, with solitary species being virtually ignored. Here, we present the first genetic study on the
mating system of any solitary mole-rats, the silvery mole-rat (Heliophobius argenteocinereus) - a species which is assumed to be monogamous. Microsatellite markers were used to analyse the mating system and the kinship
structure in populations in southern Malawi. Isolation by distance between individuals was apparent in two studied populations,
but not in the third, probably, as a result of barriers limiting dispersal in the latter population. Polygyny was found to
be a mating system in this population, where a strongly female-biased adult sex ratio was present. In this case, large distances
between the burrow systems of mating partners exclude the possibility of belowground searching for mates, suggesting that
the males might seek females aboveground. Interestingly, among analysed litters from various localities, one multiple-sired
litter was found. Therefore, the results suggest that the mating system in potentially monogamous solitary subterranean rodents
may be much more variable than expected and can differ among populations. 相似文献
993.
Iryna Kuklina Svetlana Sladkova Antonín Kouba Sergey Kholodkevich Pavel Kozák 《Environmental science and pollution research international》2014,21(17):10262-10269
The crayfish play an essential role in the biomonitoring and may reflect ambient water quality through the biochemical, behavioural and physiological reactions. To assess whether narrow-clawed crayfish Astacus leptodactylus can respond by heart rate changes to presence in water of such biocide as chloramine-T, adult males were exposed to its low (2 and 5 mg L?1), moderate (10 mg L?1, commonly used in industry and aquaculture) and exceeded (20 and 50 mg L?1) concentrations. In addition, a physical stress test evaluated energy expenditure following the chemical trials. Three key reactions (cardiac initial, first-hour and daily prolonged exposure) were discussed with particular focus on crayfish initial reaction as the most meaningful in on-line water quality biomonitoring. After short-term exposure to both chloramine-T concentrations, crayfish were found to respond rapidly, within 2–5 min. According to heart rate changes, the 1-h exposure did not adversely affect crayfish at either concentration, as well as during daily exposure to 10 mg L?1. As assessed by the heart rate, the 24-h exposure to 50 mg L?1 of chloramine-T was toxic for crayfish and led to substantial loss of energy that became apparent during subsequently conducted physical stress. The results supported a hypothesis that crayfish vital functions are connected with environment they inhabit closely enough to serve as biological monitors. Crayfish were tolerant to short-term chloramine-T exposure, while rapid crayfish reaction to an increased chemical level indicated their high sensitivity, an essential attribute of real-time environmental assessment. 相似文献
994.
M.C. Barros A. Magán S. Valiño P.M. Bello J.J. Casares J.M. Blanco 《Journal of Cleaner Production》2009,17(3):391-399
A Best Available Techniques (BAT) analysis of a mussel canning processing facility in northwest Spain was undertaken to investigate potential cleaner production and efficiency improvements. Potential techniques were identified from the literature and from our experience in the seafood sector. BATs were then assessed for possible implementation in a mussel canning facility. This work describes, in considerable detail, the advantages and disadvantages of the techniques discussed. 相似文献
995.
The aim of this paper is to evaluate the soybean production and industrial processing stages in Brazil using the emergy accounting methodology and economic cost and revenue estimation in order to assess the environmental and economic inputs to the soybean chain and to evaluate the amount of emergy and nutrients exported to European countries. The main findings of this work were that the agricultural stage uses the highest amount of resources. The emergy exchange ratio shows that farmers are delivering around six times more emergy in the soybean that is being sold than the emergy they are receiving with the money paid for it. Results demonstrate that producing raw soybean and soy meal for international markets makes Brazil lose a great amount of emergy and nutrients. Besides that, soybean production is nowadays providing low profitability to farmers because of low prices for soybean products and high prices for the chemicals used in soybean farming. Therefore, at present conditions, exporting soybean as a commodity results in low profit per unit of area. 相似文献
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