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141.
Accurate estimations of the abundance of threatened animal populations are required for assessment of species’ status and vulnerability and conservation planning. However, density estimation is usually difficult and resource demanding, so researchers often collect data at local scales. However, anthropogenic pressures most often have landscape-level effects, for example, through habitat loss and fragmentation. We applied hierarchical distance sampling (HDS) to transect count data to determine the effect of habitat and anthropogenic factors on the density of 3 arboreal primate species inhabiting 5 distinct tropical forests across a landscape of 19,000 km2 in the Udzungwa Mountains of Tanzania. We developed a novel, multiregion extension of HDS that allowed us to model density and detectability jointly across forests without losing site-specific information. For all species, the effect of anthropogenic disturbance on density was overwhelmingly negative among metapopulations: −0.63 Angolan colobus (Colobus angolensis palliatus) (95% Bayesian CI −1.03 to −0.27), −0.54 Udzungwa red colobus (Procolobus gordonorum) (−0.89 to −0.22), and −0.33 Sykes' monkey (Cercopithecus mitis monoides) (−0.63 to −0.07). Some responses to habitat factors were shared, notably the negative effect of elevation and the positive effect of climber coverage. These results are important for conservation science and practice because: the among-populations negative responses to anthropogenic disturbance provides a foundation for development of conservation plans that hold at the landscape scale, which is a comprehensive and cost-efficient approach; the among-species consistency in responses suggests conservation measures may be generalized at the guild level, which is especially relevant given the functional importance of primates in tropical rainforests; and the greater primate densities in areas at low elevation, which are closer to human settlements, point to specific management recommendations, such as the creation of buffer zones and prioritization of areas for protection.  相似文献   
142.
After considering the particular problems of atmospheric pollution in megacities, i.e. agglomerations larger than 5 mio. inhabitants, with urbanization of World's population going on steadily, possibilities of active biomonitoring by means of green plants are discussed. Based on specific definitions of active and passive bioindication the chances of monitoring heavy metals in Sao Paulo megacity were demonstrated (first results published before). This is to show that there is need for increased use of bioindication to tackle the particular problems of megacities concerning environmental "health", the data to be processed according to the Multi-Markered-Bioindication-Concept (MMBC). Comparison to other work shows this approach to be reasonable.  相似文献   
143.
We present a modelling framework that combines machine learning techniques and Geographic Information Systems to support the management of an important aquaculture species, Manila clam (Ruditapes philippinarum). We use the Venice lagoon (Italy), the first site in Europe for the production of R. philippinarum, to illustrate the potential of this modelling approach. To investigate the relationship between the yield of R. philippinarum and a set of environmental factors, we used a Random Forest (RF) algorithm. The RF model was tuned with a large data set (n = 1698) and validated by an independent data set (n = 841). Overall, the model provided good predictions of site-specific yields and the analysis of marginal effect of predictors showed substantial agreement among the modelled responses and available ecological knowledge for R. philippinarum. The most influent environmental factors for yield estimation were percentage of sand in the sediment, salinity, and water depth. Our results agree with findings from other North Adriatic lagoons. The application of the fitted RF model to continuous maps of all the environmental variables allowed estimates of the potential yield for the whole basin. Such a spatial representation enabled site-specific estimates of yield in different farming areas within the lagoon. We present a possible management application of our model by estimating the potential yield under the current farming distribution and comparing it to a proposed re-organization of the farming areas. Our analysis suggests a reduction of total yield is likely to result from the proposed re-organization.  相似文献   
144.
145.
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   
146.
This paper focuses on appropriation of natural capital through construction of buildings. The ecological footprint and the Costanza natural capital concepts are applied. The environmental consequences of human settlement are currently of great concern, and a need is felt to reduce the impact of building on the environment. The embodied energy of building materials and the "land area" required to sustain their production are considered to evaluate the demand on nature of this activity. The ecological footprints of 2 typical Italian buildings are compared. The paper also focuses on how to reduce the natural capital appropriation of building construction by means of environmentally inexpensive materials, renewable energy resources, and optimization of the use of bioproductive land by construction of multistoried buildings. Finally, to allocate an environmental load of buildings, an economic evaluation of natural capital appropriation through building construction is proposed.  相似文献   
147.
Increased awareness of the importance of environmental protection and the introduction of international standards like ISO 14001 stimulated development of environmental sustainability indicators as a means to measure systems environmental performance. Here, a thermodynamic approach, emergy analysis (Odum, 1988) was used to obtain sustainability indicators able to analyse and quantify the productive and ecological performance of four famous Italian wine productions: Chianti, Brunello di Montalcino, Nobile di Montepulciano, and Barbera d'hti. The application to agricultural production was motivated by the growing need for productive and environmentally sound development in modern agriculture, in which the resource base, the environment, is preserved. The choice of wines, more precisely, grape production, is due to their importance for Italian agriculture and the economy. All the wines demonstrated a good long-term environmental sustainability, especially in view of their high quality and in comparison with the average Italian wine production. Emergy analysis proved a powerful tool for assessing environmental performance of these systems, and its use could easily be extended to other wine productions to obtain a form of environmental performance classification of this product. Systematic use of emergy analysis to assess environmental performance of different processes and products, not necessarily in agriculture, could be useful for environmental certification.  相似文献   
148.
Forest transitions may significantly contribute to climate change mitigation but also change forest use, affecting the local people benefiting from forests. We analyze forest transitions as contested processes that simplify multifunctional landscapes and alter local livelihoods. Drawing on the Theory of Access, we develop a conceptual framework to investigate practices of multifunctional forest use and the mechanisms that exclude local forest use(r)s during forest transitions in nineteenth century Austria and twenty-first century Lao PDR. Based on historical sources, interviews and secondary literature, we discuss legal, structural and social-metabolic mechanisms to exclude multifunctional forest practices, marginalizing peasants and shifting cultivators. These include, for example, the increasing enforcement of private ownership in forests or the shift from fuelwood to coal in Austria and restrictive land use planning or the expansion of private land concessions in Laos. By integrating political ecology and environmental history in forest transitions research we unravel shifting power relations connected to forest change.  相似文献   
149.
The UN Decade of Ecosystem Restoration is poised to trigger the recovery of ecosystem services and transform structural injustices across the world in a way unparalleled in human history. The inclusion of diverse Indigenous and local communities to co-create robust native seed supply systems is the backbone to achieve the goals for the Decade. Here we show how community-based organizations have co-developed native seed supply strategies for landscape restoration from the bottom-up. We draw on the interconnections over two decades of seed networks in Brazil and the emerging Indigenous participation in native seed production in Australia. From an environmental justice perspective, we provide a participatory seed supply approach for local engagement, noting local geographical, social and cultural contexts. Meeting large-scale restoration goals requires the connection between local seed production and collaborative platforms to negotiate roles, rights and responsibilities between stakeholders. An enduring native seed supply must include a diversity of voices and autonomy of community groups that builds equitable participation in social, economic, and environmental benefits.  相似文献   
150.
This paper presents an evaluation of the consistency of an urban state-of-the-art hydrocarbon (HC) emission inventory. The evaluation was conducted through the comparison of this inventory with hourly HC measurements during two summer months in the centre of Marseille, on the Mediterranean French coast. Factors of under or overestimation could be calculated for each compound on the basis of a systematic HC to HC ratio analysis. These results, associated with a deep analysis of the speciation profiles, show that most of the common and highly concentrated hydrocarbons (such as butanes) are too much predominant in the emission speciation, while the heavy and less common species (branched alkanes, substituted aromatics) are under-represented in the inventory. The urban diffuse sources appear here as one critical point of the inventories. The disagreements were shown to have a strong incidence on the representation of the air mass reactivity. In a last step, the identified uncertainties in emissions were implemented in an air-quality model for sensitivity studies. It was shown that the observed biases in the inventory could affect the regional ozone production, with a probable impact on ozone peaks of 2–10 ppbv over the area.  相似文献   
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