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361.
The Mar Piccolo is a semi-enclosed basin subject to different natural and anthropogenic stressors. In order to better understand plankton dynamics and preferential carbon pathways within the planktonic trophic web, an integrated approach was adopted for the first time by examining all trophic levels (virioplankton, the heterotrophic and phototrophic fractions of pico-, nano- and microplankton, as well as mesozooplankton). Plankton abundance and biomass were investigated during four surveys in the period 2013–2014. Beside unveiling the dynamics of different plankton groups in the Mar Piccolo, the study revealed that high portion of the plankton carbon (C) pool was constituted by small-sized (<2 μm) planktonic fractions. The prevalence of small-sized species within micro- and mesozooplankton communities was observed as well. The succession of planktonic communities was clearly driven by the seasonality, i.e. by the nutrient availability and physical features of the water column. Our hypothesis is that beside the ‘bottom-up’ control and the grazing pressure, inferred from the C pools of different plankton groups, the presence of mussel farms in the Mar Piccolo exerts a profound impact on plankton communities, not only due to the important sequestration of the plankton biomass but also by strongly influencing its structure.  相似文献   
362.
This paper aims to contribute to the ongoing debate on the protection of cultural and biological diversity, and their interconnectedness. It highlights the importance of understanding the dynamic and complex strategies that cultures are developing to protect their biocultural diversity in the face of the ongoing cultural, economic, and social reductionist transformations occurring worldwide. We analyze Totonac society in the present time, and provide evidence on how cultural revitalization processes are emerging from the grass roots, by focusing on the ceremony of the Voladores, a pre-Hispanic ritual performed by several indigenous groups in Mesoamerica. The preoccupation of Totonac communities to safeguard this millenary tradition fostered a process of dialogue, reinforced local institutions, and catalyzed the development of strategies to preserve a tree species and its habitat.  相似文献   
363.
This article focuses on the problems of water governance at a river basin level, and on the role of institutional coordination, participation and partnerships between multiple stakeholders towards sustainable water management. Its approach presupposes that institutional capacity building, strengthening coordination between government institutions (vertical and horizontal), on the one hand, and broadening participation and consolidating partnerships between public, private and civil society actors, on the other hand, is among effective tools in integrated water resource management in river basins. It explores environmental challenges, problems, emerging trends and recent institutional innovations in the Volga basin in Russia—the largest river basin in Europe. Transfer and adaptation of good practices in good water governance between the EU and Russia are discussed. This article presents some research findings and lessons learned from practice by the EC international project ‘CABRI—Cooperation along a big river: Institutional coordination among stakeholders for environmental risk management in the Volga basin’, which is assessed as one of the selected success stories of the European research.’  相似文献   
364.
The potential for agricultural landscapes to support biodiversity may vary greatly based on agricultural land use. Current knowledge suggests that agricultural composition and intensity are dominant drivers of biodiversity in agricultural landscapes, with variable effects of agricultural configuration and landscape diversity. The aim of this study was to determine the relative effects of agricultural composition, intensity, configuration, and landscape diversity on the species diversity of six distinct bird guilds on the landscape scale in a large and complex landscape in Ontario, Canada. We found that agricultural configuration, specifically patchiness of croplands, and to a lesser degree forage lands, was the strongest predictor of bird diversity for three of the six bird guilds considered (forest, shrubland, and town). The effects of increased cropland patchiness were variable, with forest and shrubland bird diversity increasing from small to moderate patchiness, and town bird diversity declining from moderate to high patchiness. Grassland birds, a group of considerable conservation concern, increased near linearly with increased agricultural land cover in the landscape, highlighting the need to consider agricultural lands in conservation planning for this species group. Woodland bird diversity declined significantly with all increasing measures of agricultural intensity, including the proportion of high-intensity agriculture and larger patches of agricultural land. Wetland birds were unique from the other guilds, showing primarily a strong association between diversity of land cover types and guild-level bird diversity. Surprisingly, increased cover of agricultural lands, which we predicted to be a dominant driver of guild-level bird diversity declines due to habitat loss, had weak, non-significant effects relative to the other land use variable being tested, except for the positive association with grassland birds. Our findings suggest that a mix of management strategies should be employed to consider the varying effects of agricultural lands on different bird guilds, such as the inclusion of agricultural land in conservation strategies for grassland species and further managing the configuration of agricultural lands to enhance biodiversity of agricultural landscapes.  相似文献   
365.
咖啡种植、加工和流通既有积极的环境影响也有消极的环境影响.寿命周期分析是可以用来找到缓解这些消极影响的途径的手段之一.一个简单模式的系统化应当有社会经济性质的附加分析加以补充.当提请人们注意与咖啡生产链有关的问题时,即使旨在找到和提出与当地需要相适应的替代办法,也不应当忘记咖啡业给咖啡种植地区以及加工(洗涤、选择、炒制、研磨和掺合)地区带来很多效益.  相似文献   
366.
Advancing land degradation in the irrigated areas of Central Asia hinders sustainable development of this predominantly agricultural region. To support decisions on mitigating cropland degradation, this study combines linear trend analysis and spatial logistic regression modeling to expose a land degradation trend in the Khorezm region, Uzbekistan, and to analyze the causes. Time series of the 250-m MODIS NDVI, summed over the growing seasons of 2000–2010, were used to derive areas with an apparent negative vegetation trend; this was interpreted as an indicator of land degradation. About one third (161,000 ha) of the region’s area experienced negative trends of different magnitude. The vegetation decline was particularly evident on the low-fertility lands bordering on the natural sandy desert, suggesting that these areas should be prioritized in mitigation planning. The results of logistic modeling indicate that the spatial pattern of the observed trend is mainly associated with the level of the groundwater table (odds?=?330 %), land-use intensity (odds?=?103 %), low soil quality (odds?=?49 %), slope (odds?=?29 %), and salinity of the groundwater (odds?=?26 %). Areas, threatened by land degradation, were mapped by fitting the estimated model parameters to available data. The elaborated approach, combining remote-sensing and GIS, can form the basis for developing a common tool for monitoring land degradation trends in irrigated croplands of Central Asia.  相似文献   
367.
This study develops a quantitative approach to the establishment of a maximum allowable thermal discharge into a freshwater body (the Beloyarsk Reservoir) incorporated in the once-through cooling technology at the Beloyarsk nuclear power plant (NPP) (South Urals, Russian Federation). The study is based on a 3-D hydrodynamic model, embracing water circulation, heat transfer, and ice-cover formation in the Beloyarsk Reservoir. The model is driven by atmospheric forcing, river runoff, and the discharge/intake of NPP cooling water. It was used to simulate the horizontal and vertical distribution of water temperature under the effect of the operation of existing (number 3) and anticipated (numbers 4 and 5) nuclear power units. The model is validated by the comparison of the computation results with observed water temperature distribution and ice-cover configuration obtained with remote sensing techniques. The model was also used to predict the future evolution of water temperature after the launching of two new power units, which, having a common cooling system, may affect each other. It was shown that the first of the new units, no. 4, will not dramatically affect the existing thermal conditions in the reservoir, while launching one more unit, no. 5, will apparently result in overheating of the reservoir water in response to the greater volume of cooling-water discharge from the two power units. Because of a specific configuration of the recirculation flow, the reservoir may fail to cope with the dissipation of the generated heat, leading to a steady (uncontrolled) rise of water temperature in the inlet channel to one of the power units. This will reduce the potential of NPP, using the once-through cooling technology, and will most likely have an adverse effect on the survival of aquatic organisms in the Beloyarsk Reservoir. Therefore, some other environment-saving technologies must be developed for removing surplus heat from the unit no. 5 of the Beloyarsk NPP.  相似文献   
368.
369.
Elena Lucchi 《Disasters》2010,34(4):973-995
Cities are fast becoming new territories of violence. 1 The humanitarian consequences of many criminally violent urban settings are comparable to those of more traditional wars, yet despite the intensity of the needs, humanitarian aid to such settings is limited. The way in which humanitarian needs are typically defined, fails to address the problems of these contexts, the suffering they produce and the populations affected. Distinctions between formal armed conflicts, regulated by international humanitarian law, and other violent settings, as well as those between emergency and developmental assistance, can lead to the neglect of populations in distress. It can take a lot of time and effort to access vulnerable communities and implement programmes in urban settings, but experience shows that it is possible to provide humanitarian assistance with a significant focus on the direct and indirect health consequences of violence outside a traditional conflict setting. This paper considers the situation of Port‐au‐Prince (Haiti), Rio de Janeiro (Brazil) and Guatemala City (Guatemala).  相似文献   
370.
Lucchi E 《Disasters》2012,36(Z1):S87-104
Given the rising numbers of crises in urban settings, Médecins Sans Frontières (MSF) is currently shifting its focus from 'why' it should intervene to 'how' it should intervene effectively in these contexts. Beyond communities affected by natural disasters and epidemics, MSF has chosen to target populations in urban settings that are affected by violence or by marginalisation and neglect: these groups appear to suffer the greatest number of severe threats to their health and well-being. Recent reflection within MSF has identified a number of key operational challenges to confront in order to respond efficiently to the needs of these populations. These include: appropriate assessments; measurable indicators of vulnerability and impact; pertinent operational approaches and medical strategies; adapted security management; and responsible closure of activities. This paper summarises the main lessons learned from working in urban settings with the principal aim of mutual sharing and understanding.  相似文献   
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