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71.
The purpose of this paper is to discuss a methodology for the implementation of a participative plan for forest use and management in a rural community. We present an experience carried out in an aboriginal community located in the “Yungas biosphere reserve” in Northern Argentina. We developed a methodology to work with the community to assess the quality of the forest resources and to find out the causes of degradation. We worked at three levels: the community council, the community, and the school. The community has a very short-term vision. The setup, the feasibility, and the implementation of the plan is highly dependent on the willingness of the community to participate. It is so far the first attempt, in Yungas region, to develop a multi-level methodology to work with local communities to implement a forest-management plan. Findings and recommendations could be useful for others who would like to work in similar contexts.  相似文献   
72.
Sediments from Polish coastal environments were classified by a quality assessment approach that took into account trace metal and organic micropollutant concentrations, grain-size distribution, and organic carbon content. Generally, no benthic organisms were found at sites where sediments were classified as heavily polluted. However, areas characterized by a moderate contamination showed a variable composition of the benthic community and changing bioaccumulation patterns; therefore, no single species found in the Gulf of Gdańsk could be considered representative of the whole benthic environment. Although sediment monitoring must be considered a suitable tool to detect hot-spot pollution areas in coastal and inland waters, it should be complemented by bioaccumulation measurements to evaluate the actual risk posed by contaminants to benthic organisms. This “biological information” allows a better appreciation of the real benthic infaunal community exposure to chemicals and can usefully complement the existing sediment quality guidelines.  相似文献   
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74.
- DOI: http://dx.doi.org/10.1065/espr2006.01.004 Background, Aim and Scope Environmental contamination by pharmaceuticals is an emerging issue. Until recently, information on medicinal substances released into the environment was scant, but several studies have now been published. Data are, however, usually scattered and a systematic approach to this subject is generally lacking. Moreover, because of differences in the prevalence of diseases, treatment habits and options, or simply for market reasons, the pollution profile can differ significantly in different countries. The aim of this work is to review the papers dealing with environmental contamination by pharmaceuticals in Italy, with the aim of providing a comprehensive view on a national scale. Methods Papers related to environmental contamination by pharmaceuticals in Italy were reviewed, in order to offer a comprehensive view of this subject. Topics included analysis, occurrence, monitoring, modelling, treatment, control of the emissions, and ecotoxicological effects of pharmaceuticals in the environment. Results and Conclusion The literature suggests that pharmaceuticals are widespread contaminants, entering the environment from a myriad of scattered points. Patients, in case of drugs for human use, or animals for veterinary drugs, are the main sources of contamination. Pharmaceuticals can be ranked according to environmental loads, predicted by multiplying sales figures by the rate of metabolism in man or animals. Priority pharmaceuticals, i.e. the molecules of concern for the environment, can be measured in waste and surface water by liquid chromatography-tandem mass spectrometry, and the loads detected are generally comparable to the predicted ones. Pharmaceuticals are designed to stimulate a response in humans and animals at low doses, with a very specific target, so the implications for human health and the environment need to be assessed. In vitro and in vivo studies suggest that pharmaceutical principles, taken singularly or in combinations, and concentrations close to those detected in the environment, may have ecotoxicological effects. The sewage system is an important point in the control of contamination, but sewage treatment plants are not able efficiently to abate a substantial part of water-borne pharmaceuticals. Several variables play a role, however, in the processes of waste water treatment, and could be specifically adjusted to improve the efficiency of drug abatement, mitigating the potential environmental hazards. Recommendation and Perspective Pharmaceuticals in the environment are becoming a subject of global concern, with potential environmental consequences. Further knowledge of the causes, occurrence and effects of drugs as environmental pollutants is necessary for a better understanding of this ecological issue, as well as to improve abatement strategies, and to mitigate subtle environmental consequences.  相似文献   
75.
Management of coastal dunes on developed coasts could effectively take advantage of comprehensive and multitemporal georeferenced data collection, which offers the possibility to relate dune data with the natural and cultural characteristics of the beach and hinterland. The recent implementation of a coastal management geodatabase for the Veneto region provides the opportunity for improving knowledge on coastal dunes on developed littoral as well as a basis for appropriate future coastal planning in the study area. The geodatabase gathers data concerning different physical, evolutionary and human aspects of the coastal zone, with a special focus on coastal dunes. Established foredunes, human-altered dunes and relict dunes are irregularly distributed along 59 km, 38% of the entire coastal length. Their distribution and characteristics are the result of favourable natural conditions as well as long-lasting tourism exploitation (evaluated through an index of Land Use Pressure) and fragmentary and diversified uses of beaches (evaluated through an index of Tourism Pressure on the beach). At the same time, beach/dune nourishment intervention allowed the presence of artificial or sand fenced dunes along 17 km of coast. High dune elevation up to 8–10 m is promoted by the onshore exposition of the beach to dominant wind (from ENE), by stable-to-slowly negative sedimentary budget or by the re-activation of high relict foredunes in the case of shoreline retreat associated with strong negative budget. Present sedimentary budget (evaluated through the code ASPE – Accretion, Stable, Precarious, Erosive) is the tool used for dividing coasts in sedimentary compartments or cells. Past and present sedimentary budget and different human responses to erosive cases (hard and soft interventions) give the foredunes different means to form, grow, survive and evolve over time. The assessment of Human Impact and Active Management Practices on the dunes allows a first evaluation of the Management Effectiveness, which shows strong shortcomings for 81% of the dunes. The great variability of beach usage, human impact and management practises on the different dune stretches highlight the lack of effective and systematic management actions being correctly scheduled and performed.  相似文献   
76.
An interesting aspect of the chemistry of nitrite is the possibility for this compound to interact with other environmental factors and many oxidising species, which results in the oxidation of nitrite to nitrogen dioxide. This is a potentially interesting process that can lead to the formation of nitroaromatic compounds in the environment. In previous papers we have shown that nitrite can interact with dissolved Fe(III) and nitrate under irradiation, Fenton and heterogeneous photo-Fenton reagents, and semiconductor oxides such as TiO2, alpha-Fe2O3, and beta-FeOOH under irradiation. This paper reports on the interaction between nitrite/nitrous acid and the Mn(III,IV) (hydr)oxides beta-MnO2 and gamma-MnOOH, both in neutral solution under irradiation and in acidic conditions in the dark. beta-MnO2 and gamma-MnOOH originate from the oxidation of Mn(II) and play a key role in the redox cycling of manganese in the environment. These Mn(III,IV) (hydr)oxides show some photocatalytic activity, and they can act as thermal oxidants at acidic pH. The photoinduced oxidation of nitrite and the thermal oxidation of nitrous acid by Mn(III,IV) (hydr)oxides yield nitrogen dioxide and lead to the formation of nitrophenols in the presence of phenol. These processes can take place at the water-sediment or water-colloid interface in natural waters and on the surface of atmospheric particulate. Furthermore, the phenol/gamma-MnOOH/HNO2 system in dark acidic solution is an interesting model due to the formation of phenoxyl radical upon phenol monoelectronic oxidation by gamma-MnOOH. The kinetics of nitrophenol generation under such conditions indicates that phenol nitration is unlikely to take place upon reaction between phenoxyl and *NO2 and suggests a solution to a literature debate on the subject.  相似文献   
77.
This study examines defoliation and discoloration findings collected throughout the Italian Level I network between 1997 and 2000. Prior to this period no Quality Assurance procedures had been implemented, so that earlier findings cannot be considered reliable. The aim of the study is to compare differentindices used in reporting findings, in order to determine the full potential and limitations of each. In international surveys,findings are normally expressed in terms of individual trees presenting a defoliation level greater than 2 %; this criterion,however, has been challenged since it is not based on scientificevidence. By analysing the distribution of defoliation values(grouped in 5% classes) relating to the main species (Fagus sylvatica, Quercus pubescens, Quercus cerris, Picea abies), the study examines the behaviour of statistical indices such as the median, the mode and the mean. Instead of using the traditional 25% threshold to determine the part of the population with the highest defoliation values, a procedureis suggested whereby a different threshold can be determined foreach species. It is established based on the 90° percentile of cumulative defoliation values recorded over the four-year period. Each index used to report findings possessesits own information potential, and the findings may at times appear contradictory. The use of a combined defoliation and discoloration index (Ilce = Lacking Crown Equivalent Index) is also proposed, but the results obtained do not differin substance from the results relating to defoliation alone. Thefunctional limitations of this index are due mainly to the way the data are collected: for this reason suggestions are made onhow to improve the procedure in future surveys.  相似文献   
78.
Interactions between meio- and macrofaunal assemblages and food availability were investigated in relation to tourism pressures on three beaches of the northern Adriatic Sea. All beaches were characterised by the presence of artificial reefs, freshwater inputs and tourism pressures. Beach sediments displayed high organic loads and low protein and chlorophyll a contributions to the bulk of the organic matter. Consequently, the organic matter was of mostly refractory composition and, thus, of scarce nutritional quality. Macrofaunal community structure and biomass were related to the quantity and nutritional quality of sedimentary organic matter, whereas meiofauna was apparently not. No relationships were found between physical variables and the metazoan communities. Most likely, the presence of artificial reefs reduced the physical impact of waves on the beach assemblages, whereas the presence of synergistic human impacts, including freshwater inputs and the tourism pressure, negatively influenced both the meio- and the macrofaunal assemblages.  相似文献   
79.
The carbonate radical (CO 3 ) is a photoinduced transient species occurring in surface waters. The carbonate radical can transform both natural compounds and xenobiotics. For instance, it can react with electron-rich substrates such as anilines, phenols and organic sulfur compounds. Here we used the APEX software to assess photochemical reactions, including the formation rates of transient species, based on water chemistry and depth, under summertime irradiation conditions. We found that the reaction between peroxynitrite and carbon dioxide is a potentially significant source of CO 3 in sunlit surface waters, and could account for up to 10–15 % of the total CO 3 formation. The peroxynitrite pathway to CO 3 would be most significant at pH 7–8 and would be enhanced in waters with elevated nitrate and low alkalinity. Therefore, the proposed process could add to the known photochemical sources of CO 3 in surface-water environments.  相似文献   
80.
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