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391.
392.
Many questions relevant to conservation decision-making are characterized by extreme uncertainty due to lack of empirical data and complexity of the underlying ecologic processes, leading to a rapid increase in the use of structured protocols to elicit expert knowledge. Published ecologic applications often employ a modified Delphi method, where experts provide judgments anonymously and mathematical aggregation techniques are used to combine judgments. The Sheffield elicitation framework (SHELF) differs in its behavioral approach to synthesizing individual judgments into a fully specified probability distribution for an unknown quantity. We used the SHELF protocol remotely to assess extinction risk of three subterranean aquatic species that are being considered for listing under the U.S. Endangered Species Act. We provided experts an empirical threat assessment for each known locality over a video conference and recorded judgments on the probability of population persistence over four generations with online submission forms and R-shiny apps available through the SHELF package. Despite large uncertainty for all populations, there were key differences between species’ risk of extirpation based on spatial variation in dominant threats, local land use and management practices, and species’ microhabitat. The resulting probability distributions provided decision makers with a full picture of uncertainty that was consistent with the probabilistic nature of risk assessments. Discussion among experts during SHELF's behavioral aggregation stage clearly documented dominant threats (e.g., development, timber harvest, animal agriculture, and cave visitation) and their interactions with local cave geology and species’ habitat. Our virtual implementation of the SHELF protocol demonstrated the flexibility of the approach for conservation applications operating on budgets and time lines that can limit in-person meetings of geographically dispersed experts.  相似文献   
393.
The aim of the study was to assess the content, distribution, soil binding capacity, and ecological risk of cadmium and lead in the soils of Malopolska (South Poland). The investigation of 320 soil samples from differently used land (grassland, arable land, forest, wasteland) revealed a very high variation in the metal content in the soils. The pollution of soils with cadmium and lead is moderate. Generally, a point source of lead and cadmium pollution was noted in the study area. The highest content of cadmium and lead was found in the northwestern part of the area—the industrial zones (mining and metallurgical activity). These findings are confirmed by the arrangement of semivariogram surfaces and bivariate Moran’s correlation coefficients. Among the different types of land use, forest soils had by far the highest mean content of bioavailable forms of both metals. The results showed a higher soil binding capacity for lead than for cadmium. However, for both metals, extremely high (class 5) accumulation capacities were dominant. Based on the results, the investigated soils had a low (Pb) and moderate (Cd) ecological risk on living components. Soil properties, such as organic C, pH, sand, silt, and clay content, correlated with the content of total and bioavailable forms of metals in the soils. The correlations, despite being statistically significant, were characterized by very low values of correlation coefficient (r?=?0.12–0.20, at p?≤?0.05). Therefore, the obtained data do not allow to define any conclusions as to the relationships between these soil properties. However, it must be highlighted that there was a very strong positive correlation between the total content of cadmium and lead and their bioavailable forms in the soils.  相似文献   
394.
It is generally recognised by the disaster risk management and development communities that disasters have a negative impact on development, and indeed can set back development by years. This realisation led to a new paradigm for the management of hazards and their impacts, namely an integrated approach which emphasises disaster risk reduction being incorporated into national development planning. Awareness, however, does not necessarily translate into implementation. ‘Reduce the underlying risk factors’, Priority for Action 4 of The Hyogo Framework for Action 2005–2015, reported the lowest average score for progress of the five priority areas. Challenges to progress, as reported by Governments included inappropriate development practices, high levels of poverty and other factors which increase vulnerability. Various authors have recognised the difficulty of consistently and successfully integrating disaster risk reduction into development planning. This integration is particularly challenging for Small Island Developing States (SIDS) which face high exposure to hazards, vulnerable populations and limited resources, often both human and financial. The efforts of Jamaica, a Caribbean SIDS, at integrating disaster risk reduction into national development, and some factors which proved to be important in making progress are presented here. This retrospective paper is written from the perspective of a participant observer and traces developments in disaster risk management over three decades, 1980–2010. Integration and inclusiveness, use of quantitative methods and application of risk assessments are identified as being important in gaining acceptance for disaster risk reduction.  相似文献   
395.
Europe has a long history of human pressure on freshwater ecosystems. As pressure continues to grow and new threats emerge, there is an urgent need for conservation of freshwater biodiversity and its ecosystem services. However, whilst some taxonomic groups, mainly vertebrates, have received a disproportionate amount of attention and funds, other groups remain largely off the public and scientific radar. Freshwater mussels (Bivalvia, Unionida) are an alarming example of this conservation bias and here we point out six conceptual areas that need immediate and long-term attention: knowledge, threats, socioeconomics, conservation, governance and education. The proposed roadmap aims to advance research, policy and education by identifying the most pressing priorities for the short- and long-term conservation of freshwater mussels across Europe.  相似文献   
396.
In natural resource management facilitation literature, little attention is paid to sensitive issues in multi-stakeholder interaction and learning. This article aims to fill this gap. It discusses the variety of discursive strategies used by stakeholders to address sensitive issues with regard to fishery management in Benin, in three different settings: individual interviews, homogeneous groups' discussions, and a heterogeneous group meeting. Issues that proved sensitive were discussed openly in the interviews or homogeneous groups' discussions, but not at all, or only indirectly, in the heterogeneous group meeting. With indirect discursive strategies, two out of the seven sensitive issues were put on the discussions' agenda. We conclude that the other issues were too sensitive among others because of historically grown interdependency between interventionists and fishers. We suggest that dealing with sensitive issues is an important dimension of the facilitation of interactive learning processes and provide methodological guidelines to detect and address such issues.  相似文献   
397.
The content of elements in fish tissues and organs from Swarz?dzkie Lake was investigated in order to evaluate the possible risk associated with their consumption by animals as well as humans. Samples of muscle, liver and fish bone of three fish species; roach (Rutilus rutilus), silver bream (Blicca bjoerkna) and crucian carp (Carassius carassius) were collected from seine catches undertaken as part of the biomanipulation of Swarz?dzkie Lake. Element concentration (Al, As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Zn) was determined by inductively coupled plasma mass spectrometry (ICP-MS), with the exception of Hg where the flow injection analysis system cold vapour atomic absorption spectrometry (FIAS-CVAAS) was applied. The study indicated a large variation in the occurrence of the investigated elements in different parts of the fish body. The highest content of Al and Zn was stated in all fish organs for each fish species. The majority of the applied statistical and chemometric methods (e.g., PCA, CA) refer to roach since we had a large number of data for this species. The obtained results were assessed in terms of their accuracy and precision using certified reference material of Fish Muscle ERM BB422.  相似文献   
398.
399.
Environmental Science and Pollution Research - The paper presents the studies on 210Po and 210Pb activity determination in red-capped scaber (Leccinum aurantiacum (Bulliard) Gray) collected in...  相似文献   
400.
Seed and fruit dispersal along watercourses favours the long-distance migration of invasive species, not only for aquatic or wetland species, but also for terrestrial wind-dispersed plants, like the Japanese knotweed. The present paper aims at investigating the role of watercourses in the dispersal of the knotweed due to its frequent occurrence on riverbanks and production of fertile achenes (type of fruit of the Japanese knotweed). This dispersal occurs along two steps after the fruits deposit on the water surface: floatation first and then sinking towards the bottom of the watercourse. Regarding the first step, the effects of agitation of the water, temperature, surface tension and luminosity on the achenes floatability are experimentally studied. While no influence of luminosity is observed, an increase of temperature greatly decreases the floating time. Floating time also decreases as the contact between water and the fruit is enhanced (through submersion of achenes, agitation of the water or lower surface tension). Regarding the second step, the fall velocity of the fruits in water at rest is measured and appears to be independent of the seed history (floating time). 3D helical motions are systematically observed with constant tangential velocity with respect to the falling velocity. The trajectory of the fruits in a shear flow is then measured and the evolution of their velocity components along the sinking process is discussed. Finally, the contribution of both steps to the long-distance migration of the seeds is estimated.  相似文献   
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