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871.
The integration of local harvesters' knowledge of attitudes and practices toward the resources they harvest with scientific information is essential to natural resources management. However, the development and implementation of management policies have, in most cases, not been effective because of a failure to use all available sources of information and knowledge. In fisheries management, local knowledge is usually not collected in a systematic format and little published literature has discussed the use of local knowledge data collection and analysis methods. This paper describes the implementation of geographic information systems to systematize, analyze, and display traditional and scientific information to support fisheries management in the Patos Lagoon Estuary, southern Brazil. Artisanal fishing data were documented through a series of interviews conducted during and after fishing trips at harvest spots, and scientific data on environmental variables were obtained from different research institutions. A multi-layer GIS database integrating local fishers' and scientific knowledge information was developed with ArcGIS 8.3 ArcView tools to integrate and translate information into an accessible and interpretable format. The geo-spatial database interface allowed the selection of specific data characteristics by target species, harvest areas, fishers' communities, fishing gear, catch-per-unit of effort (CPUE), and monthly landings. The observed fishing spatial dynamics presented among the fishers' communities shows that, in most cases, artisanal fishermen tend to concentrate in shallow estuarine waters surrounding their villages. 相似文献
872.
Johan De Tavernier 《Journal of Agricultural and Environmental Ethics》2009,22(4):383-388
873.
Bert Schreurs Eva Derous Edwin A. J. Van Hooft Karin Proost Karel De Witte 《组织行为杂志》2009,30(6):761-783
Applicants' pretest expectations about the forthcoming selection procedure may serve as a key factor in applicants' decision‐making. The current study examined the validity of the theory of planned behavior (TPB) as an explanatory mechanism of the relationship between pretest selection expectations (warmth/respect, chance to demonstrate potential, difficulty of faking, unbiased assessment, feedback) and job pursuit behavior. Data were collected at two points in time, using a sample of applicants for the military. Selection expectations, job pursuit attitude, subjective norm, and controllability were significantly related to job pursuit intention. Job pursuit attitude mediated the relationship between selection expectations and job pursuit intention. Subjective norm and time lag were the only significant predictors of job pursuit behavior. Practical implications, strengths and limitations, as well as directions for further research are discussed. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
874.
Influence of temperature and soil type on the toxicity of three pesticides to Eisenia andrei 总被引:1,自引:0,他引:1
P. Mangala C.S. De Silva Asoka Pathiratne Cornelis A.M. van Gestel 《Chemosphere》2009,76(10):1410-1415
Expansion of agriculture in the tropics has increased the use of pesticides that may affect the soil ecosystems. Few studies so far determined the effects of pesticides in the tropics and tropical risk assessment therefore often relies on data from temperate conditions. Hence we compared the toxicity of chlorpyrifos, carbofuran and carbendazim to the earthworm Eisenia andrei at two different temperatures reflecting temperate and tropical conditions. The toxicity of the three pesticides in both conditions decreased in the order carbendazim > carbofuran > chlorpyrifos. For chlorpyrifos and carbofuran, but not for carbendazim, survival was more sensitive at the higher temperature, probably due to increased earthworm activity. Sub-lethal effects (reproduction and growth) however, varied inconsistently with temperature and soil types. We conclude that toxicity of pesticides in tropics may not be predicted from data generated under temperate conditions, even within the same species. 相似文献
875.
876.
Vulnerability and risk evaluation of agricultural nitrogen pollution for Hungary's main aquifer using DRASTIC and GLEAMS models 总被引:5,自引:1,他引:4
Leone A Ripa MN Uricchio V Deák J Vargay Z 《Journal of environmental management》2009,90(10):2969-2978
In recent years, the significant improvement in point source depuration technologies has highlighted problems regarding, in particular, phosphorus and nitrogen pollution of surface and groundwater caused by agricultural non-point (diffuse) sources (NPS). Therefore, there is an urgent need to determine the relationship between agriculture and chemical and ecological water quality.This is a worldwide problem, but it is particularly relevant in countries, such as Hungary, that have recently become members of the European Community. The Italian Foreign Ministry has financed the PECO (Eastern Europe Countries Project) projects, amongst which is the project that led to the present paper, aimed at agricultural sustainability in Hungary, from the point of view of NPS. Specifically, the aim of the present work has been to study nitrates in Hungary's main aquifer. This study compares a model showing aquifer intrinsic vulnerability to pollution (using the DRASTIC parameter method; Aller et al. [Aller, L., Truman, B., Leher, J.H., Petty, R.J., 1986. DRASTIC: A Standardized System for Evaluating Ground Water Pollution Potential Using Hydrogeologic Settings. US NTIS, Springfield, VA.]) with a field-scale model (GLEAMS; Knisel [Knisel, W.G. (Ed.), 1993. GLEAMS—Groudwater Leaching Effects of Agricultural Management Systems, Version 3.10. University of Georgia, Coastal Plain Experimental Station, Tifton, GA.]) developed to evaluate the effects of agricultural management systems within and through the plant root zone. Specifically, GLEAMS calculates nitrate nitrogen lost by runoff, sediment and leachate.Groundwater monitoring probes were constructed for the project to measure: (i) nitrate content in monitored wells; (ii) tritium (3H) hydrogen radioisotope, as a tool to estimate the recharge conditions of the shallow groundwater; (iii) nitrogen isotope ratio δ15N, since nitrogen of organic and inorganic origin can easily be distinguished.The results obtained are satisfactory, above all regarding the DRASTIC evaluation method, which is shown to satisfactorily explain both low and high aquifer vulnerability, and furthermore proves to be a good tool for zoning hydrogeological regions in terms of natural system susceptibility to pollution. The GLEAMS model, however, proves not to be immediately usable for predictions, above all due to the difficulty in finding sufficient data for the input parameters. It remains a good tool, but only after an accurate validation, for decision support systems, in the specific case to integrate intrinsic vulnerability, from DRASTIC (or similar methods), with land use nitrate loads from GLEAMS, or similar methods.The PECO project has proved a positive experience to highlight the fundamental points of a decision support system, aimed to mitigate the nitrate risk for groundwater coming from Hungarian agricultural areas. 相似文献
877.
Bruno De Cordier 《Disasters》2009,33(4):608-628
This paper focuses on the emergence and modus operandi of Muslim faith-based aid organisations from the West, particularly those from the United Kingdom. Through case studies of Islamic Relief Worldwide and Muslim Hands, it examines the actual and potential added value generated by these humanitarian players in Muslim-majority contexts at times when aid actors from or associated with the West are being perceived by some as instrumental to the political agendas of Western powers, or are being confronted with the consequences thereof. The study analyses Muslim faith-based aid organisations' transnational networks, their implementing partnerships with local faith-based non-governmental organisations (NGOs), and their security position within and their access to insecure contexts, drawing on field examples and opinion from Central Asia, Iraq and Pakistan. It thereby argues that there is ground for an expansion of the role of Muslim aid actors, because of the existence of social and political realities in the field that cannot be always effectively tackled by the dominant international development approaches. 相似文献
878.
Cinzia De Vittor Federica Relitti Martina Kralj Stefano Covelli Andrea Emili 《Environmental science and pollution research international》2016,23(13):12566-12581
In the shallow environment, the nutrient and carbon exchanges at the sediment–water interface contribute significantly to determine the trophic status of the whole water column. The intensity of the allochthonous input in a coastal environment subjected to strong anthropogenic pressures determines an increase in the benthic oxygen demand leading to depressed oxygen levels in the bottom waters. Anoxic conditions resulting from organic enrichment can enhance the exchange of nutrients between sediments and the overlying water. In the present study, carbon and nutrient fluxes at the sediment–water interface were measured at two experimental sites, one highly and one moderately contaminated, as reference point. In situ benthic flux measurements of dissolved species (O2, DIC, DOC, N-NO3 ?, N-NO2 ?, N-NH4 +, P-PO4 3?, Si-Si(OH)4, H2S) were conducted using benthic chambers. Furthermore, undisturbed sediment cores were collected for analyses of total and organic C, total N, and biopolymeric carbon (carbohydrates, proteins, and lipids) as well as of dissolved species in porewaters and supernatant in order to calculate the diffusive fluxes. The sediments were characterized by suboxic to anoxic conditions with redox values more negative in the highly contaminated site, which was also characterized by higher biopolymeric carbon content (most of all lipids), lower C/N ratios and generally higher diffusive fluxes, which could result in a higher release of contaminants. A great difference was observed between diffusive and in situ benthic fluxes suggesting the enhancing of fluxes by bioturbation and the occurrence of biogeochemically important processes at the sediment–water interface. The multi-contamination of both inorganic and organic pollutants, in the sediments of the Mar Piccolo of Taranto (declared SIN in 1998), potentially transferable to the water column and to the aquatic trophic chain, is of serious concern for its ecological relevance, also considering the widespread fishing and mussel farming activities in the area. 相似文献
879.
880.