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111.
High-conservation-value forests (HCVFs) are critically important for biodiversity and ecosystem service provisioning, but they face many threats. Where systematic HCVF inventories are missing, such as in parts of Eastern Europe, these forests remain largely unacknowledged and therefore often unprotected. We devised a novel, transferable approach for detecting HCVFs based on integrating historical spy satellite images, contemporary remote sensing data (Landsat), and information on current potential anthropogenic pressures (e.g., road infrastructure, population density, demand for fire wood, terrain). We applied the method to the Romanian Carpathians, for which we mapped forest continuity (1955–2019), canopy structural complexity, and anthropogenic pressures. We identified 738,000 ha of HCVF. More than half of this area was identified as susceptible to current anthropogenic pressures and lacked formal protection. By providing a framework for broad-scale HCVF monitoring, our approach facilitates integration of HCVF into forest conservation and management. This is urgently needed to achieve the goals of the European Union's Biodiversity Strategy to maintain valuable forest ecosystems.  相似文献   
112.
Single territories contribute in different ways to the transition towards a more environmentally sustainable development (SD), according to their structural features. This study returns a multi-dimensional picture of the territorial divides of environmental sustainability across Italy, analysing how it correlates with rurality, with a focus on the urban–rural continuum. Italy represents an interesting case study because of its peculiar territorial urban–rural structure. We first assess the environmental sustainability targets across Italian NUTS 3 regions and their capital cities using two composite sustainability indexes, by referring to both standard values (i.e. conforming to legislation) and optimum values (i.e. desired values). Then, we investigate the relationship between environmental sustainability and rurality. Results suggest that a positive link between the two exists, being stronger at city level. Among major policy implications, the environmental dimensions of territorial cohesion should be integrated more strongly in key European policies to reach a more balanced SD.  相似文献   
113.
In 1991 a co‐operation between Public Health Office (U.S.S.L.) n° 18 of Brescia and the Chemical Section Laboratories of U.S.S.L. n° 38 of Milan concerning the possible environmental impact of foundry industrial activities performing metallic scraps recovering, has been undertaken.

Soil and surfaces have been classified in conformity with the National Toxicological Consultative Commission (C.C.T.N.) recommendation dated 12/02/1988'; owing to the characteristics of the processed material, besides heavy metals, polychlorodibenzo‐p‐dioxins (PCDDs), polychlorodibenzofurans (PCDFs) and polychlorobiphenyls (PCBs) have been looked for.

The particulate matter collected from the filters positioned over the arc furnaces in 14 foundry plants has been characterized and classified, according both to C.C.T.N.1 and to the Interministerial Board regulation dated 27/07/1985 for the first application of the Republic President Decree Law (D.P.R.) n° 915/1982, concerning wastes classification, based, in this case, on these toxic chlorinated compounds concentrations. From the very beginning, high levels of PCDDs and PCDFs have been detected, corroborating the very few literature data from foundry plants2. The results obtained on 14 different foundries allow us to draw already some information, acceptable from the point of view of the statistical validity, about the pollution produced by this industry.  相似文献   
114.
Coastal ecosystems can be thought of as being established by a number of physico-geochemical drivers, e.g. geochemistry and bathymetry of the basins, climate, tidal and freshwater flows, natural and anthropogenic inputs of nutrients and toxins, all of which exert an influence on the resulting communities of organisms. Depending on the interactions among the major drivers, ecosystems may occur on both large and small scales and be basin-wide or within basins. For individual and separate ecosystems to exist with some permanence in time, e.g. reach a steady-state, they also have to be ‘defended’. Defences are mechanisms that counter changes to maintain the status quo. We argue, and present evidence to support the notion, that the defence mechanisms are inextricably tied to primary production and the biogeochemical cycling of organic matter and provide buffers that mitigate potentially adverse impacts by trace toxins. Colloid pumping, production of complexing ligands and sulfide formation are some of the mechanisms that control trace substances. Current methods for assessing ecosystems do not address the issue of steady-state, nor do they take account of defence activities, e.g. buffering. Therefore, they cannot assess the ‘robustness’ of ecosystems or their ability to resist change, for good or bad. Also, defence mechanisms may, for a time, mask future potentially serious impacts, suggesting that monitoring efforts with limited budgets should consider the measurement of the inputs into ecosystems as well as the immediate or short-term result of the inputs.  相似文献   
115.
116.
Among procellariiform seabirds, many burrowing petrels show good olfactory abilities especially in recognising their nest. In particular, it has been reported that Antarctic prions (Pachyptila desolata) discriminate their own and their mate’s odours and, in Y-maze experiments, prefer the odour of a conspecific bird to their own. While traditionally examined from the perspective of homing mechanisms, these recent results have drawn attention to the possible use of chemical signals in birds’ social behaviours. Indeed, the life history of petrels suggests that a mate choice mediated by olfactory mechanisms may have evolved in this group to ensure genetic compatibility. This study was undertaken to validate and extend results obtained on petrels’ olfactory discrimination capabilities. Following the Y-maze experiment protocol, blue petrels (Halobaena caerulea) were offered three different choices: (1) mate versus conspecific’s odour, (2) own versus mate’s odour and (3) own versus conspecific’s odour. We discovered that birds prefer the odour of their mate not only when presented against conspecific’s odour but also against their own. We further verified that blue petrels also avoid their own odour when presented against conspecific’s odour. Our results confirm that olfactory discrimination in burrowing petrels goes beyond self-recognition and that self-odour avoidance may be widespread. We use two mutually non-exclusive behavioural frameworks for the interpretation of our results, homing and mate choice, and explain why homing mechanisms cannot account for all of our observations. This study opens the door to further research on olfactory mechanisms that, in petrels, might mediate individual recognition and mate choice.  相似文献   
117.
We investigate the effect of environmental policies on innovation under different levels of competition. Using information regarding renewable energy policies, competition and green patents for OECD countries since the late 1970s, we develop a pre-sample mean count-data econometric specification that accounts for the endogeneity of policies. We find that renewable energy policies are more effective in fostering green innovation in countries with liberalized energy markets. We also find that environmental policies are crucial only in the generation of high-quality green patents, whereas competition enhances the generation of low-quality green patents.  相似文献   
118.
The nutrient and pesticide abatement efficiency of varying mixtures was examined in a vegetated free water surface constructed wetland. Three different agricultural chemical pollutant mixture conditions were assessed: nutrients only (N and P); pesticides only (atrazine, S-metolachlor and permethrin); and a mixture of nutrients and pesticides. With nutrients only, 672 h nutrient mitigation of 77–91% total phosphorous (TP) and 74–98% total nitrogen (TN) was associated with distance from the injection point and rainfall, whereas with nutrient and pesticide mixtures, 672 h nutrient mitigation of 11–71% TP and 84–98% TN were associated with distance and time. With pesticides only, 672 h pesticide mitigation of 50–99% was associated with distance and time, whereas with nutrients and pesticide mixtures, 672 h pesticide mitigation of 48–99% was associated primarily with distance. Dissipation half-lives were 2–10 times greater for P and 1.5–5 times greater for N when pesticides were present. Pesticide dissipation half-lives showed no clear differences with or without nutrients. While vegetated free water surface constructed wetlands can be effective best management practice tools to trap and abate agricultural run-off during rainfall events, efficiencies can be affected by different types of complex pollutant mixtures and wetland design and implementation should accommodate varying efficiencies.  相似文献   
119.
Some mathematical models for the estimation of the effects of Cry1Ab and Cry1F Bt-maize exposure in the biodiversity are examined. Novel results about these models are obtained and described in this note. The exact formula for the proportion of population that suffers mortality exposed either to Cry1Ab or Cry1AF pollen is derived. Moreover, regarding Cry1F pollen effects, the species sensitivity of Lepidoptera is discussed.  相似文献   
120.
The recent high-resolution multibeam bathymetry surveys around Lipari Island allowed to evidence several submarine canyons, whose head often cut back up to very shallow water and at a few tens of meters far from the coast. These canyons are mainly located in the eastern and southern side of the island and are characterized by an ongoing retrogressive (landward) erosion, that also controlled the shape and the evolution of the coastline. The canyon heads are formed by minor slide scars. By coupling slide scar morphometry and simple numerical model we have been able to roughly estimate the potential tsunami wave amplitudes generated by related slope failures. Moreover, the retrogressive erosion of canyon heads can be claimed as a cause of the enhanced subsidence reported in the last few thousand years in the eastern part of Lipari, where the main villages are located. Based on these evidence, we propose a first assessment of the coastal hazard due to marine retrogressive activity in the largest and most densely populated island of the Aeolian Archipelago.  相似文献   
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