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121.
Mercury (Hg) was determined in adult Bonelli's eagles (Hieraaetus fasciatus) and their avian prey, from samples of feathers collected between 1992 and 2001 at the nesting sites of 21 pairs in Southwest Portugal. Eagle Hg levels showed great variation, reflecting primarily differences in diet composition and food chain biomagnification. Concentrations were positively correlated with the dietary proportion of insectivorous and omnivorous birds (e.g. egrets, corvids and thrushes), with very low levels for pairs feeding mainly on herbivores (e.g. rabbits, pigeons and partridges). Differences in prey contamination among breeding territories added to dietary effects in determining variation of Hg levels in eagles, shaping a spatial pattern that was largely consistent with a source of contamination in a coal-burning power-plant lying upwind of the study area. Despite this presumed contamination, Hg levels seemed to be of little concern to this eagle population, though there might be subtle deleterious effects on the reproductive output of a few pairs. This study emphasizes the need to account for dietary effects when biomonitoring Hg contamination using birds of prey.  相似文献   
122.
The investigation of the long-term performance of solidified/stabilized (S/S) contaminated soils was carried out in a trial site in southeast UK. The soils were exposed to the maximum natural weathering for four years and sampled at various depths in a controlled manner. The chemical properties (e. g. , degree of carbonation (DOC), pH, electrical conductivity (EC)) and physical properties (e. g. , moisture content (MC), liquid limit (LL), plastic limit (PL), plasticity index (PI)) of the samples untreated and treated with the traditional and accelerated carbonated S/S processes were analyzed. Their variations on the depths of the soils were also studied. The result showed that the broad geotechnical properties of the soils, manifested in their PIs, were related to the concentration of the water soluble ions and in particular the free calcium ions. The samples treated with the accelerated carbonation technology (ACT), and the untreated samples contained limited number of free calcium ions in solutions and consequently interacted with waters in a similar way. Compared with the traditional cement-based S/S technology, e. g. , treatment with ordinary portland cement (OPC) or EnvirOceM, ACT caused the increase of the PI of the treated soil and made it more stable during long-term weathering. The PI values for the four soils ascended according to the order: the EnvirOceM soil, the OPC soil, the ACT soil, and the untreated soil while their pH and EC values descended according to the same order.  相似文献   
123.
The aim of the present study was to investigate the inhibitory activity of lactic acid bacteria (LAB) isolated from brewer's grains on Aspergillus section Flavi growth and aflatoxin B1 production. The Aspergillus strains tested were inhibited by all the LAB strains assayed. The isolates Lactobacillus brevis B20, P. pentosaceus B86, Lactococcus lactis subsp. lactis B87, L. brevis B131, and Lactobacillus sp. B144 completely suppressed the fungal growth and reduced aflatoxin B1 production. In conclusion, LAB isolated from brewer's grains show a high inhibitory activity on fungal growth and aflatoxin biosynthesis by Aspergillus flavus and Aspergillus parasiticus. Further studies must be conducted to evaluate the success of in vitro assays under food environment conditions and to elucidate the antifungal mechanism of these strains.  相似文献   
124.
Environmental Science and Pollution Research - Flow cytometry has recently been presented as a research tool in the assessment of the viability/activity of activated sludge from municipal...  相似文献   
125.
In spite of its wide-world economic relevance, wine production generates a huge amount of waste that threatens the environment. A batch experiment was designed to assess the effect of the amendment of an agricultural soil with two winery wastes (perlite and bentonite wastes) in the immobilization of cyprodinil. Waste addition (0, 10, 20, 40, and 80 Mg ha?1) and different times of incubation of soil-waste mixtures (1, 30, and 120 days) were tested. The addition of wastes improved the soil’s ability to immobilize cyprodinil, which was significantly correlated to total C content in soil-waste mixtures. Longer incubation times decreased the cyprodinil sorption possibly due to the mineralization of organic matter but also as a consequence of the high pH values reached after bentonite waste addition (up to 10.0). Cyprodinil desorption increased as the amount of waste added to soil, and the incubation time increased. The use of these winery wastes contributes to a more sustainable agriculture preventing fungicide mobilization to groundwater.  相似文献   
126.
Regional Environmental Change - The Intergovernmental Panel on Climate Change (IPCC) projections of global mean temperature rises are worrisome for coffee crop due to the intolerance of the Arabica...  相似文献   
127.
Integrative research is increasingly a priority within the scientific community and is a central goal for the evolving field of sustainability science. While it is conceptually attractive, its successful implementation has been challenging and recent work suggests that the move towards interdisciplinarity and transdisciplinarity in sustainability science is being only partially realized. To address this from the perspective of social-ecological systems (SES) research, we examine the process of conducting a science of integration within the Southcentral Alaska Test Case (SCTC) of Alaska-EPSCoR as a test-bed for this approach. The SCTC is part of a large, 5 year, interdisciplinary study investigating changing environments and adaptations to those changes in Alaska. In this paper, we review progress toward a science of integration and present our efforts to confront the practical issues of applying proposed integration frameworks. We: (1) define our integration framework; (2) describe the collaborative processes, including the co-development of science through stakeholder engagement and partnerships; and (3) illustrate potential products of integrative, social-ecological systems research. The approaches we use can also be applied outside of this particular framework. We highlight challenges and propose improvements for integration in sustainability science by addressing the need for common frameworks and improved contextual understanding. These insights may be useful for capacity-building for interdisciplinary projects that address complex real-world social and environmental problems.  相似文献   
128.
The present study investigates the application of a noncommercial peroxidase enzyme, which was extracted from rice bran, to decolorize wastewater that was simulating effluent from a textile manufacturer using a red dye in its coloration process.  相似文献   
129.
Local ecological knowledge (LEK) has been found to be one of the main bridges to manage biocultural diversity. We analyzed the factors affecting LEK maintenance and transmission in a Mediterranean watershed. We used a mixed methods approach to evaluate the agricultural LEK in three different dimensions: biological, soil and water management, and forecasting. We found that the main factors for its maintenance were the respondent''s time living in the area and the social relationships established among farmers, which involved partner collaboration and farmer information exchanges. Protected areas also played a key role for maintaining the LEK associated with soil and water management. Finally, we found that outmigration and mechanization were the most important indirect drivers of change underlying LEK erosion. We suggest that environmental policies should focus on promoting this experiential knowledge, considering both intergenerational renewal and the gendered aspects of this knowledge.

Electronic supplementary material

The online version of this article (doi:10.1007/s13280-014-0556-1) contains supplementary material, which is available to authorized users.  相似文献   
130.
A study was conducted to evaluate the effects of dietary nitrocompounds on bird performance, ammonia volatilization, and changes in manure nitrogen (N). A total of 200 one-day-old male chicks (Cobb 500) were used for this study. The chicks were raised in electrically heated battery brooders for 18 days. On day 1, birds were allocated into five treatment groups with four replicated pens: (T1) control, a corn and soybean meal diet (3,100 kcal kg?1 metabolizable energy (ME) and 21% Crude Protein (CP)); (T2) 16.7 mg kg?1 nitroethanol (NEL); (T3) 33.3 mg kg?1 NEL; (T4) 16.7 mg kg?1 nitropropanol (NPL); and (T5) 33.3 mg kg?1 NPL. The body weight gain, feed intake and feed efficiency were measured on days 7, 14 and 18. Volatized ammonia (VA) and other N forms were measured at collection and following 2 weeks of incubation at 30°C. Broiler growth was not adversely affected by the nitrocompounds at concentrations up to 33.3 mg kg?1. The results show that initial manure pH was reduced by adding nitroethanol (NEL) and nitropropanol (NPL) to the diet by 0.2 and 0.5 pH units, respectively. Total VA after 2 weeks was unaffected by dietary treatment. The amounts of uric acid decomposed and ammonia produced were closely balanced in the control sample. However, this balance was significantly different among the manures produced by birds receiving nitrocompound treatments. The inclusion of NEL and NPL resulted in the presence of measurable amounts of Xanthine not found in the control group. This study indicates that supplementation of nitroethanol or nitropropanol into broiler diets up to 33.3 mg kg?1 influences uric acid degradation and ammonia production in broiler manure while maintaining optimal growth performance.  相似文献   
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