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141.
The present work presents the results of 137Cs concentration in seawater, fish and sediments samples collect in 11 sampling points, crossing the Brazilian Southeastern coastal region, from Vitória (ES) to Santos (SP), on a routine basis from 1997 to 2002. This monitoring program was carried out by the Instituto de Radioproteção e Dosimetria (IRD/CNEN/MCT), in cooperation with the Instituto de Estudos do Mar Almirante Paulo Moreira (IEAPM/Brazilian Navy), aiming at determining artificial radionuclides in marine samples. Additionally to the 137Cs results, 90Sr concentrations in fish samples from 1998 to 2002 are also reported.The 137Cs in seawater follows a lognormal distribution, with a geometric mean of 1.8 Bq m-3 and a geometric standard deviation of 1.4 (n=54), decay corrected to June/2002. For 137Cs levels in fish samples a geometric mean of 0.19 Bq kg−1 and a geometric standard deviation of 2.9 (n=39), decay corrected to June/2002, with a range of 0.03 to 1.7 Bq kg−1, were obtained. Based on the 137Cs mean concentration in fish as well as in seawater, a transfer factor of 1 × 102 was calculated, which is quite in agreement with the recommended value found in the Safety Report Serie 19.  相似文献   
142.
The Philippine fisheries accounted for 3.7% of the gross national product at current prices. The sector employed about 990,872 persons. Of the divisions comprising the industry, municipal fisheries continued to contribute the largest share of fish production. However, the sector is beset with problems, many of which are best examplified by the case of San Miguel Bay (SMB). This paper presents the problems and constraints confronting SMB, a common property resource. This bay's open access condition has led to various problems, such as declining fishery resources, depressed socioeconomic conditions, illegal fishing, increasing population, and conflict among resource users. A poor marketing system, low level of fishing technology, fishermen's noncompliance and authorities' lax enforcement of rules and regulations, as well as lack of alternative sources of income further characterize the condition in SMB. Establishment of fishing rights, improvement of the marketing system, provision of alternative sources of income, and improvement of fishing technology were some of the solutions suggested. One major constraint, however, is financial, Comanagement complemented with other management tools has been proposed in addressing the problems in SMB.  相似文献   
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Environment, Development and Sustainability - Even though ecosystem services have a significant contribution to human well-being, their value is not always recognized. Despite difficulties, the...  相似文献   
145.
All processes in agro-industries consume water and generate large volumes of nutrient-rich effluents. To recycle effluents from a sugar–alcohol industry in the Northeastern Brazil (Coruripe, Alagoas), the effect of a daily application of a microbial formulation (containing five indigenous bacteria and two fungi), at the entrance of the two first facultative ponds (D, E) of its treatment plant formed by seven ponds (A–G), was evaluated in the sugarcane harvests of 2014/2015 and 2015/2016. Fortnightly, the values of 11 physicochemical parameters were checked and statistically compared (one and two-way ANOVA) in untreated (sedimentation pond A) and post-treated effluent (last facultative pond G), during both harvests. The treated effluent presented statistically significant improvements (p > 0.05), even between harvests, with averages of removal of organic matter of ca. 79.21% and 90.62%, and increases of the dissolved oxygen (DO) of ca. 72% and 74%, as well as the average increase of pH was ca. 42% and 50%. This better quality residue generally satisfied the class III level of the Brazilian Resolution 357/2005 (National Council for the Environment (CONAMA)), for water reuse in sugarcane irrigation on the yellow clay latosol soil, since it still is a light source of organic matter, nitrites and phosphorus, reducing the need of fertilizers for maintaining the productivity with low risk of salinization. According to Pearson’s bivariate correlation coefficient, while the DO and pH have positive correlation, they both have general inverse relation with the other physicochemical parameters evaluated and vice versa.  相似文献   
146.
Conservation biology was founded on the idea that efforts to save nature depend on a scientific understanding of how it works. It sought to apply ecological principles to conservation problems. We investigated whether the relationship between these fields has changed over time through machine reading the full texts of 32,000 research articles published in 16 ecology and conservation biology journals. We examined changes in research topics in both fields and how the fields have evolved from 2000 to 2014. As conservation biology matured, its focus shifted from ecology to social and political aspects of conservation. The 2 fields diverged and now occupy distinct niches in modern science. We hypothesize this pattern resulted from increasing recognition that social, economic, and political factors are critical for successful conservation and possibly from rising skepticism about the relevance of contemporary ecological theory to practical conservation.  相似文献   
147.
Environmental Science and Pollution Research - Metal uptake capacity and growth patterns of three cardoon cultivars (Sardo, Siciliano, and Spagnolo) were investigated for phytoremediation in a...  相似文献   
148.
Mining generates risk of environmental and social harm for Indigenous peoples but can also generate substantial revenues for them, creating opportunities for community development in a context where economic and social disadvantage is the norm. Especially as mining revenues should, in part, compensate for mining’s negative social and environmental impacts, it is vital that mineral taxation on Indigenous lands reflect a careful assessment of appropriate tax mechanisms and a matching of these with community priorities. Yet little has been written that could serve as a guide for Indigenous decision makers. This article contributes to an understanding of the issues and choices facing Indigenous communities in designing mineral taxation regimes, by focusing on the question of economic risk. Risk arises as a key variable in choosing or designing a mineral taxation regime in three ways. Different approaches to mineral taxation are inherently more or less risky, in the sense that they are more or less certain to generate tax revenues. A second aspect of risk involves the degree of economic certainty or predictability associated with different types of commodities and projects. Third, the risk tolerance of Indigenous peoples and communities can vary significantly. We show how Indigenous groups can integrate and address these different dimensions of risk, by recognising the ‘risk consequences’ associated with different approaches to mineral taxation and choosing an approach that reflects, as fully as possible, the group’s risk tolerance.  相似文献   
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Water is a precious resource in arid rural areas with irrigated agriculture. Nonetheless, water and agricultural policies in Europe show different management scopes and objectives, usually translated in divergent drivers of rural change. This paper has a double aim: to propose a specific method for quantitative biophysical analysis of water use in rural systems with the multi-scale integrated analysis of societal and ecosystem metabolism approach and to show the usefulness of this method for the assessment of the integration of water and agricultural policies. The river basin scale is chosen, since it is the socioecological unit for water management established in the water framework directive 2000/60/CE. A multi-scale water use accounting is provided for a Mediterranean river basin in Andalusia, integrating water cycle, ecosystems and social levels. Particularly focusing on agricultural production, a relevant set of indicators is proposed in order to analyze and compare different metabolic patterns. Finally, the integration of water and agricultural planning is assessed in terms of external (biophysical) and internal (economic, institutional) constraints of the new water-use patterns generated by the scenarios posed in these policies. While on a European level water policy is ambitious in terms of ecological conservation, the lack of integration within the common agricultural policy and the entanglement of multiple scales of political and economic organization of local ruralities blur its priority in a rather slow transition to a new water culture.  相似文献   
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