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371.
Chemical monitoring of water quality on a total of 16 rivers in the Azores archipelago (Portugal), since 2003, made it possible to identify the major pressures and spatial geochemical variations along main course of the rivers. River water pollution is to a large extent associated to point sources, namely domestic wastewater discharges, especially in urban areas, and diffuse sources, associated with pasture land, and explain the high values on BOD(5) and nutrients (P and N). Heavy metals and metalloids, as well as hydrocarbons and pesticides, are generally under the detection limits of the analytical methods. Generally, river water reflects pollution loads according to a simple model, derived from land use in the watershed: in the upper part conditions are pristine, in the intermediate portion of the basin pasture land dominates and near the coast urban discharges are increasingly important. Results stress the role that an approach based on the watershed scale, coupled with land use management measures, are crucial to water management procedures and a successful WFD implementation in small river basin districts like the Azores. The paper also shows the need for full compliance regarding EU directives on urban wastewater and nitrate pollution due to agriculture.  相似文献   
372.
The main objective of this work was to quantify and characterize the major indoor air contaminants present in different stages of a municipal WWTP, including microorganisms (bacteria and fungi), carbon dioxide, carbon monoxide, hydrogen sulfide ammonia, formaldehyde, and volatile organic compounds (VOCs). In general, the total bacteria concentration was found to vary from 60 to >52,560 colony-forming units (CFU)/m3, and the total fungi concentration ranged from 369 to 14,068 CFU/m3. Generally, Gram-positive bacteria were observed in higher number than Gram-negative bacteria. CO2 concentration ranged from 251 to 9,710 ppm, and CO concentration was either not detected or presented a level of 1 ppm. H2S concentration ranged from 0.1 to 6.0 ppm. NH3 concentration was <2 ppm in most samples. Formaldehyde was <0.01 ppm at all sampling sites. The total VOC concentration ranged from 36 to 1,724 μg/m3. Among the VOCs, toluene presented the highest concentration. Results point to indoor/outdoor ratios higher than one. In general, the highest levels of airborne contaminants were detected at the primary treatment (SEDIPAC 3D), secondary sedimentation, and sludge dehydration. At most sampling sites, the concentrations of airborne contaminants were below the occupational exposure limits (OELs) for all the campaigns. However, a few contaminants were above OELs in some sampling sites.  相似文献   
373.
Environment, Development and Sustainability - The activated biochar is a carbonaceous material obtained from thermal degradation of biomass with high adsorption potential. On the other hand, the...  相似文献   
374.
Collaborative planning theory and co-management paradigms promise conflict prevention and the incorporation of indigenous knowledge into plans. Critics argue that without devolved power to culturally legitimate institutions, indigenous perspectives are marginalized. Co-management practice in North America is largely limited to treaty-protected fish and wildlife because federal agencies cannot devolve land management authority. This paper explores why the Pueblo de Cochiti, a federally recognized American Indian Tribe, and the U.S. Bureau of Land Management sustained an rare joint management agreement for the Kasha-Katuwe Tent Rocks National Monument in New Mexico despite a history of conflict over federal control of customary tribal lands that discouraged the Pueblo from working with federal agencies. Based on the participant interviews and documents, the case suggests that clear agreements, management attitudes, and the direct representation of indigenous forms of government helped achieve presumed co-management benefits. However, parties enter these agreements strategically. We should study, not assume, participant goals in collaborative processes and co-management institutions and pay special attention to the opportunities and constraints of federal laws and institutional culture for collaborative resource management with tribal and local communities.  相似文献   
375.
Concentrations of polybrominated diphenyl ethers (PBDEs) in Forster’s tern (Sterna forsteri) eggs from San Francisco Bay have been reported to range up to 63 μg g−1 lipid weight. This value exceeds the lowest-observed-adverse-effect level (1.8 μg g−1 egg wet weight; ∼32 μg−1 lipid weight) reported in an embryotoxicity study with American kestrels (Falco sparverius). As a surrogate for Forster’s terns, common tern (Sterna hirundo) eggs were treated by air cell injection with corn oil vehicle (control) or a commercial penta-BDE formulation (DE-71) at nominal concentrations of 0.2, 2, and 20 μg g−1 egg. As a positive control, kestrel eggs received vehicle or 20 μg DE-71 g−1 egg. In terns, there were no effects of DE-71 on embryonic survival, and pipping or hatching success; however, treated eggs hatched later (0.44 d) than controls. Organ weights, organ-to-body weight ratios, and bone lengths did not differ, and histopathological observations were unremarkable. Several measures of hepatic oxidative stress in hatchling terns were not affected by DE-71, although there was some evidence of oxidative DNA damage (8-hydroxy-deoxyguanosine; 8-OH-dG). Although DE-71 did not impair pipping and hatching of kestrels, it did result in a delay in hatch, shorter humerus length, and reduced total thyroid weight. Concentrations of oxidized glutathione, reduced glutathione, thiobarbituric acid reactive substances, and 8-OH-dG in liver were greater in DE-71-treated kestrels compared to controls. Our findings suggest common tern embryos, and perhaps other tern species, are less sensitive to PBDEs than kestrel embryos.  相似文献   
376.
The use of forest land for ecotourism has been well accepted due to its ability to provide income to local people and to conserve the forest. Preparing the forest with infrastructure to attract and educate visitors has been reported of importance. This study applied Q methodology in a small rural community of the State of Puebla, Mexico, to reveal forest owners’ perceptions to build infrastructure in their forest as part of their ecotourism project. It also discloses forest owners’ underlying motives to use their forest for ecotourism. Ecotourism is perceived as a complementary activity to farming that would allow women to be involved in community development. Low impact infrastructure is desired due to forest owners’ perception to preserve the forest for the overall community well-being.  相似文献   
377.
A key characteristic of global organic agriculture governance through standards is the coexistence of regulatory fragmentation and regional integration. To reduce barriers to organic trade, especially for market participants from developing countries, international and transnational entrepreneurs increasingly promote the setting of organic agriculture standards (OAS) in different world regions, for example, in East Africa, the Pacific, or Asia. Although scholars from different disciplines have done a lot of research on the role of standards in global governance, we still know little about why and how regional standard-setting processes evolve. Applying findings from regime analysis, entrepreneurship, and political authority, the article introduces the concept of authority pooling. It argues that legal, moral, and technical authority sources interact in a blurred functional division of labour between the public and the private sector in standard-setting. The article presents results from a within-case study of the development of the East African Organic Products Standard using the process-tracing method. It detects the underlying causal mechanism by which international and transnational entrepreneurs pooled different authority sources and, thus, significantly influenced political actors in East Africa to set the first regional OAS in the developing world.  相似文献   
378.
When planning interventions, water and land resource managers increasingly need to take the opinions of stakeholders into account. In the present study, stakeholders’ concerns in a multifunctional water system are assessed, with a focus on the debate about the sustainability of irrigation projects in stressed and competing water contexts. The selected case study pertains to the Segarra‐Garrigues irrigation canal (Spain), the promotion of which has generated social debate and mobilization, as well as pronouncements from European authorities for ensuring its environmental sustainability. Data was collected through semi‐structured interviews and analysed by means of a new codification system for identifying the affinities and conflicts arising from existing water demands. Results show that sustainability concepts are more present in civil society than in public administration and private services or the rural community. However, social sustainability and environmental sustainability are a priority for most stakeholders, while the economic perspective of sustainable development has been conditioned by the first two. These results can be used by relevant authorities as a first step in customizing their interventions, as they provide a clear initial idea of what stakeholder priorities are in the framework of sustainable development.  相似文献   
379.
Abstract

The pervasiveness of the plasticizer di‐(2‐ethylhexyl) phthalate (DEHP) in the environment and especially in the laboratory results in a background that may cause severe interference with analytical studies. Animal‐to‐animal variability in the distribution of DEHP metabolites in excreta normally makes it necessary to use large groups of animals when different treatments are compared. Finally, radioactive tracers are usually considered undesirable for metabolic studies involving human subjects. All of these problems can be overcome through the use of muliple isotopic labels, especially 12C/13C/14C. Examples are given involving rats and monkeys, and applicability to humans is discussed. The principles involved are not limited to any particular class of test compounds. In rats, the competing pathways for metabolism of phthalate esters produce a different distribution of metabolites from a small intravenous dose of DEHP than from a large oral dose.  相似文献   
380.
Abstract

This paper presents the results of the first reported study on fine particulate matter (PM) chemical composition at Salamanca, a highly industrialized urban area of Central Mexico. Samples were collected at six sites within the urban area during February and March 2003. Several trace elements, organic carbon (OC), elemental carbon (EC), and six ions were analyzed to characterize aerosols. Average concentrations of PM with aerodynamic diameter of less than 10 μm (PM10) and fine PM with aerodynamic diameter of less than 2.5 μm (PM2.5) ranged from 32.2 to 76.6 μg m-3 and 11.1 to 23.7 μg m-3, respectively. OC (34%), SO4 = (25.1%), EC (12.9%), and geological material (12.5%) were the major components of PM2.5. For PM10, geological material (57.9%), OC (17.3%), and SO4 = (9.7%) were the major components. Coarse fraction (PM10 –PM2.5), geological material (81.7%), and OC (8.6%) were the dominant species, which amounted to 90.4%. Correlation analysis showed that sulfate in PM2.5 was present as ammonium sulfate. Sulfate showed a significant spatial variation with higher concentrations to the north resulting from predominantly southwesterly winds above the surface layer and by major SO2 sources that include a power plant and refinery. At the urban site of Cruz Roja it was observed that PM2.5 mass concentrations were similar to the submicron fraction concentrations. Furthermore, the correlation between EC in PM2.5 and EC measured from an aethalometer was r2 = 0.710. Temporal variations of SO2 and nitrogen oxide were observed during a day when the maximum concentration of PM2.5 was measured, which was associated with emissions from the nearby refinery and power plant. From cascade impactor measurements, the three measured modes of airborne particles corresponded with diameters of 0.32, 1.8, and 5.6 μm.  相似文献   
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