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201.
Agri-environmental measures (AEM) are incentive-based instruments in the European Union (EU) that provide payments to farmers for voluntary environmental commitments related to preserving and enhancing the environment and maintaining the cultural landscape. We review the AEM literature and provide an overview of important research topics, major research results and future challenges as discussed in the available literature concerning these measures. This review contributes to the existing literature by attempting to equally consider ecological and economic perspectives. The reviewed articles are analyzed regarding their regional focus, topics and methods. The analytical section of the article seeks to discuss commonly asked questions about AEM on the basis of results from reviewed studies. The vast amount of available literature provides valuable insights into specific cases and reveals a complex picture with few general conclusions. The existing research is usually either biased toward ecological or economic perspectives and fails to provide a holistic picture of the problems and challenges within agri-environmental programming (e.g., multiple measures, multiple target areas, legal aspects, financial constraints, transaction costs). Most empirical studies provide detailed insights into selected individual measures but are incapable of providing results at a level relevant to decision-making, as they neglect the role of farmers and the available AEM budget. Predominantly economic approaches often only consider rough assumptions of ecological and economic processes and are also not suitable for decision-making. Decision-support tools that build on these disciplinary results and simultaneously consider scheme factors and environmental conditions at high spatial resolution for application by the responsible authorities are rare and require further research.  相似文献   
202.
Journal of Polymers and the Environment - The aim of the present study was to perform morphological and chemical characterizations of microplastics (MPs) found in seawater samples from the coast of...  相似文献   
203.
Environmental Science and Pollution Research - Land use changes have led to the degradation of multiple ecosystem services and affected the quality of aquatic ecosystems. The aims of this study...  相似文献   
204.
The biological availability of metals in municipal wastewater effluents is strongly influenced by the physical and chemical conditions of both the effluent and the receiving water. Aquatic organisms are exposed to both dissolved and particulate (food ingestion) forms of these metals. In the present study, the distribution of metals in specific tissues was used to distinguish between exposure routes (i.e. dissolved vs. particulate phase) and to examine metal bioavailability in mussels exposed to municipal effluents. Caged Elliptio complanata mussels were deployed at sites located between 1.5 km upstream and 12 km downstream of a major effluent outfall in the St. Lawrence River. Metals in surface water samples were fractionated by filtration techniques to determine their dissolved, truly-dissolved (<10 kDa), total-particulate and acid-reactive-particulate forms. At the end of the exposure period (90 days), pooled mussel soft tissues (digestive gland, gills, gonad, foot and mantle) were analyzed for several metals. The results showed that gills and digestive gland were generally the most important target tissues for metal bioaccumulation, while gill/digestive gland metal ratios suggest that both exposure routes should be considered for mussels exposed to municipal effluents. We also found that Ag and Cd in the dispersion plume nearest the outfall, in contrast to other metals such as Cu and Zn, are more closely associated with colloids and were generally less bioavailable than at the reference site in the St. Lawrence River.  相似文献   
205.
The efficacy of ozonation and of photocatalysis processing in the treatment of pulp mill ECF (elementary chlorine free) bleaching and textile effluents was evaluated by determining total organic carbon reduction (TOC) and the toxicity. The chronic toxicity of the effluents was evaluated by the ability to inhibit the growth of algae Selenastrum capricornutum. Cultured hamster V79 fibroblasts were used to assess the cytotoxicity of effluents submitted to different detoxification processes. Two endpoints were measured in V79 cells: 3-(4,5-dimethylthiazole-2-yl)-2,5-biphenyl tetrazolium bromide (MTT) reduction and neutral red uptake (NRU). Both treatment processes were able to reduce the TOC, although ozonization was less effective for pulp mill ECF bleaching. The pulp mill ECF bleaching and textile effluents reduced the growth of S. capricornutum by 39% and 27%, respectively. However, at the highest concentration tested, the textile effluents treated by photochemical process for 60 min showed increased cytotoxicity in V79 cells compared to the untreated effluent when assessed by the NRU and MTT reduction assays (increases of 30% and 40%, respectively). Pulp mill ECF bleaching effluent treated by ozonization had a similar cytotoxicity to that of untreated effluent in the NRU assay. In contrast, the MTT reduction assay indicated that effluents treated with ozone were around 20% more cytotoxic than untreated effluents. These results show that cultured fibroblasts may be useful for studying cellular responses to pollutants and may be included in tests to monitor the efficiency of effluent detoxification processes.  相似文献   
206.
The BIODEP model in terms of atmosphere-lake interactions was developed. The model was applied to an oligotrophic, dimictic high altitude lake (Lake Redo, Pyrenees) for a range of polychlorinated biphenyl (PCB) congeners. High altitude lakes, which receive their contaminant inputs uniquely from the atmosphere through long-range atmospheric transport, provide ideal controlled environments for the study of the interactions between atmospheric depositional and water column biogeochemical processes. The BIODEP model was able to predict dissolved water concentrations and PCB accumulation in the lake sediment within a factor of 2. This shows that the BIODEP model captures the essential processes driving the sink of POPs in high altitude lakes and that POP occurrence in the lake is driven by direct atmospheric inputs with limited influence from the watershed. An important seasonal variability in water column concentrations is predicted which should have important implications in sampling strategies. Furthermore, it is shown that diffusive air-water exchange dominated the PCB dynamics in the lake, especially for the less chlorinated biphenyls.  相似文献   
207.
208.
A refugium is generally understood as an area where temperate species survive cold periods, such as the Iberian, Italian, or Balkan Peninsulas in Europe. Strictly speaking, this definition refers to what is known as a glacial refugium. However, there are various types of lesser-known refugia such as the interglacial refugium, which denotes a mountainous region at low latitudes, such as the Pyrenees, where species adapted to the cold survive during interstadial periods. The small-vertebrate association from the sequence of Cova Colomera, which is located on the southern face of the Pyrenees and contains the final cold spell of the Late Pleistocene and the beginnings of the temperate period in which we currently find ourselves (the Holocene), could constitute the first fossil evidence of such an interglacial refugium, thus providing new paleoecological data on the phenomenon.  相似文献   
209.
ABSTRACT: Aquatic monitoring aims to assess the condition of aquatic habitats and biota. To make statements about condition, the range of human activities and the risks they pose to aquatic ecosystems must be identified. Assessing relative risk and placing sample sites on a human disturbance gradient is necessary for interpreting biological response and distinguishing human disturbance from natural controls in aquatic systems. We describe a process that uses readily available sources, such as topographic maps, aerial photographs, and field information, to identify and prioritize stream reach and watershed stressors for 102 streams in the mid-Appalachian region of the United States. All perceptible human alterations to riparian and upland areas along with their number, type, intensity, and extent of impact were recorded and ranked; a relative risk index was developed to assign scores to the watersheds. The resulting risk index scores were consistent with measures of stream condition based on water chemistry and benthic macroinvertebrates. The risk index gives a cost-effective, regional picture of the relative risk of impairment to aquatic ecosystems in the mid-Appalachian region of the USA and could be modified for other regions or ecosystem types.  相似文献   
210.
Holt–Oram syndrome or atriodigital dysplasia is commonly associated with cardiac malformations, most often with defects of the muscular septum. We describe the case of a fetus referred for fetal cardiology evaluation in the setting of right atrial enlargement without tricuspid valve abnormalities with small muscular VSDs, and without other significant cardiac lesions. On serial fetal echocardiograms, isolated right atrial enlargement was persistent as was relative fetal bradycardia without apparent AV block or other signs of abnormal conduction. Limb or other anatomic abnormalities were also not visualized on prenatal scans. A postnatal diagnosis of Holt–Oram Syndrome was made. In the setting of isolated right atrial enlargement, we suggest a comprehensive sonographic search for upper limb abnormalities as well as genetic evaluation.  相似文献   
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