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1.
Geometric morphometrics has been used to reveal coupled geographic variation in the mandible shape in two sympatric rodent species, the pygmy wood mouse (Sylvaemus uralensis Pall.) and bank vole (Myodes glareolus Pall.), in the Southern Urals. It has been shown that syntopic samples synchronously collected from the local communities of these species usually display similar, parallel, and unidirectional morphological changes as demonstrated by comparison of species pairs from different localities. The degree of concordance in geographic variation of the species makes it possible to estimate their coevolutionary potential within local communities: the wider the range of ecological conditions under which parallel variation of sympatric species is observed, the higher is their coevolutionary potential.  相似文献   

2.
On the basis of syntaxonomy of primary forests in the Southern Ural region, an analysis of trends in the formation of their species diversity has been performed in regard to heat supply, soil moisture, and general soil richness. The roles of environmental factors have been estimated using Landolt’s scales. The results have shown that communities of forest classes Querco-Fagetea, Brachypodio-Betuletea, and Vaccinio-Piceetea differ in the trends of changes in species richness along gradients of the above factors. In communities of all these classes, species richness depends primarily on heat supply, with soil richness being the second most important factor.  相似文献   

3.
Adaptive strategies of cyclomorphic rodent populations (Rodentia) under extreme conditions of droughts (in 1975 and 2010) have been analyzed on the basis of functional–ontogenetic approach. The following features of these strategies have been revealed: minimization of metabolic processes, block of sexual maturation, intergenerational crossing, prolongation of breeding period, and species-specific features in the dynamics of intrapopulation processes. Profound changes in the level of long-term oscillations of abundance after the drought have been noted in different species. Evidence is provided for the possibility of extremely rapid population rearrangements on an evolutionary scale that are fixed in a series of generations.  相似文献   

4.
Some up-to-date methods of analysis of the spatial and age structures of populations, including local population density maps and Ripley’s functions, are described using 20 cenopopulations (CPs) of Adonis vernalis L. as an example. Pregenerative plants have been found to be the most contagious, irrespective of climatic and phytocenotic conditions and land use type. The spatial distribution pattern and structure of A. vernalis are mainly determined by generative plants forming a tussock, irrespective of the climate and vegetation type. This is explained by higher competitiveness of generative plants, which results in a reduced vegetation density at small distances from them (25–50 cm). Within wider areas, plant distribution may be random due to uniformity of local conditions in microhabitats. The formation of distinct plant aggregations is accounted for by insufficient water supply and the intensity and type of anthropogenic impact.  相似文献   

5.
Ecological economics is a field of enquiry that has had, with a few exceptions, an almost entirely terrestrial focus. Given the fundamental ecological and economic importance of oceanic and coastal ecosystems, and the accelerating deterioration of these ecosystems, we argue that there is an urgent case to redress this imbalance. In so doing, the scope of ecological economics will be extended and compelling insights developed and applied to better understand and govern marine systems. Although we acknowledge that there is no unequivocal or unitary view of what might constitute an ecological economics of the oceans and coasts, we assert that it should consist of at least ‘four cornerstones’: (1) sustainability as the normative goal; (2) an approach that sees the socio-economic system as a sub-system of the global ecological system; (3) a complex systems approach; and (4) transdisciplinarity and methodological pluralism. Using these four cornerstones, we identify a future research agenda for an ecological economics of the oceans and coasts. Specifically, we conclude that ecological economists must work with other disciplines, especially those involved in marine policy and practice, to move from a ‘frontier economics’ (which has dominated marine management) to entrench an ‘ecological economics’ of the oceans and coasts as the dominant paradigm.  相似文献   

6.
It is well known that the incorporation of the intergenerational equity objective has turned the traditional Cost–Benefit Analysis (CBA) approach into an obsolete tool for the evaluation of certain types of projects, particularly those exhibiting many environmental externalities and those whose effects extend throughout a long period of time. Two main changes are taking place in CBA in order to adapt this methodology to the sustainable development paradigm: (a) the development of new tools for the economic valuation of environmental externalities that were traditionally left out of the analysis; and (b) an in-depth revision of the theoretical foundations underlying the traditional approaches to discounting, since the repercussions of decisions that are presently being debated will extend to a distant future (in some cases for centuries), whereas in the classical CBA, we deal with few decades at best. This paper aims at investigating the discounting operation in CBA, trying to summarize the main approaches available in the literature, with specific reference to the tools which allow future generations to be included in the analysis. In order to support the theoretical explanation, a real case study is analysed concerning the evaluation of a waste incinerator that has been constructed in the Province of Turin (Italy).  相似文献   

7.
In seven higher plant species of different taxa, structural features of underground organs have been considered, and the levels of intraspecific variation in some characters of these organs have been determined. Different pathways of the structural adaptation of these species to the environment are demonstrated on the morphological and anatomical levels.Translated from Ekologiya, No. 2, 2005, pp. 97–105.Original Russian Text Copyright © 2005 by Tarshis.  相似文献   

8.
The distribution of morphological, substrate, and latitudinal geographic groups of lichen species has been analyzed in various habitat types on the northwestern coast of the Sea of Japan. The results show that the influence of the sea manifests itself in the presence of halophytes, xerophytic life forms, and species of the suboceanic latitudinal geographic group; soil-plant conditions account for the development of the substrate group of epiphytic lichens, mesophytic life forms, and species of the nemoral latitudinal geographic group.  相似文献   

9.
Mobile coastal dunes are of significant ecological importance both globally and locally. Yet a large portion of these dunes are disappearing due to encroachment of local shrubs and exotic plants, resulting in changes of floristic and faunal composition, and an overall decrease in biodiversity of coastal systems. Active management is therefore required to maintain mobile dune presence. This study focuses on economic valuation of coastal dunes in Israel, based on public and professional ecological perspectives. This comparison allows reflection on the suitability of a contingent valuation method (CVM) to assess ecological restoration and conservation projects. The CVM was applied in Nizzanim LTER nature reserve in Israel, and concurrently, data of plant species composition on stabilized and mobile dunes were used to calculate the ecological value index (EVI) of the different dune states. The EVI was then transformed into monetary terms by combining the public valuation and the relative proportion of the various species to the total coverage. The monetary values derived from the general public and the ecological assessment were then compared and used to estimate the expected change in economic value resulting from a state shift from mobile to stabilized dunes. According to the CVM, the total value of the Nizzanim coastal dunes would drop from 344 to 197 million Israeli Shekels (NIS) (1 Shekel = $0.39) if active management does not take place, a reduction of 42 % in value. However, results from the EVI indicate only a 33 % decrease in ecological value (in monetary terms) in the absence of active management. We suggest that in this case, general public perception is strong enough to justify conservation decisions, even though they are not professional ecologists. However, we still recommend the use of both measures for land use decision making.  相似文献   

10.
The contents of ten metals in the bone and muscle tissues were studied in three fish species from a water body located in the impact zone of a copper smelter. In the course of principal component analysis with “tissue” and “species” taken as instrumental variables (IVs), a high proportion of unexplained IV variance was revealed for xenobiotic elements, and the procedure of optimal scaling by the CATPCA method allowed their pattern to be estimated. It is proposed to use the unexplained variance of multidimensional data on the chemical composition of organisms for identifying the pattern of xenobiotics in environmental objects.  相似文献   

11.
Methods of geometric morphometrics have been used to compare the ranges and directions of geographic and technogenic forms of variation in the morphology of the mandible in Ural populations of pygmy wood mice (Sylvaemus uralensis Pall.) exposed to different types of pollutants (radionuclides, fluorides, and toxic petrochemical products). The range of variation in the mandible morphology consequent to chronic radiation exposure in the zone of the Eastern Ural Radioactive Trace is commensurate to the range of geographic variation of the species observed in the Middle and Southern Urals. Unspecific manifestations of variation have been revealed, which apparently result from exposure to technogenic pollutants of different origin. A probable contribution of technogenic variation to rapid morphogenetic rearrangements in populations is discussed.  相似文献   

12.
Environment, Development and Sustainability - This study assessed the vulnerability of five indigenous agroforestry trees to climate change: Adansonia. digitata, Vitellaria paradoxa, Parkia...  相似文献   

13.
Environmental risk assessment and decision-making strategies over the last several decades have become increasingly more sophisticated, information-intensive, and complex, including such approaches as expert judgment, cost-benefit analysis, and toxicological risk assessment. One tool that has been used to support environmental decision-making is comparative risk assessment (CRA), but CRA lacks a structured method for arriving at an optimal project alternative. Multi-criteria decision analysis (MCDA) provides better-supported techniques for the comparison of project alternatives based on decision matrices, and it also provides structured methods for the incorporation of project stakeholders' opinions in the ranking of alternatives. We argue that the inherent uncertainty in our ability to predict ecosystem evolution and response to different management policies requires shifting from optimization-based management to an adaptive management paradigm. This paper brings together a multidisciplinary review of existing decision-making approaches at regulatory agencies in the United States and Europe and synthesizes state-of-the-art research in CRA, MCDA, and adaptive management methods applicable to environmental remediation and restoration projects. We propose a basic decision analytic framework that couples MCDA with adaptive management and its public participation and stakeholder value elicitation methods, and we demonstrate application of the framework to a realistic case study based on contaminated sediment management issues in the New York/New Jersey Harbor.  相似文献   

14.
The ecological phytoindication scales proposed by Tsyganov (1983) were used for characterizing biotopes at the northern limit of the distribution of three nemoral species:Ajuga reptans, Asarum europaeum, andPulmonaria obscura. Regional ecological amplitudes of the model species were determined. The environmental factors approaching the lower limit of species amplitudes in Tsyganov's scales were classified as unfavorable.  相似文献   

15.
The causes and ecological consequences of alien plant species invasions in the Southern Urals are analyzed. Aggressive invasive species of North American origin??Ambrosia trifida L., A. psylostachya DC., Cyclachaena xanthiifolia (Nutt.) Fresen., Hordeum jubatum L., Oenothera biennis L., Bidens frondosa L., etc.??have invaded synanthropic and natural plant communities and became dominant, with their proportion varying from 10 to 99%. The biomass of these plants may reach 6 kg/m2; density, more than 1000 shoots per square meter; and seed production, up to 30000 seeds per plant, which explains their dominance in communities. The ecological hazard they pose lies in the displacement of native species, overgrowing of disturbed land areas, and allergenicity of their pollen.  相似文献   

16.
The saturation of herbaceous communities with adventive species in the Northern Caucasus has been estimated using as an indicator the number of such species in 0.5-m2 plots. Among factors accounting for variation in the test parameter, consideration has been given to the coverage of the herbaceous layer, the species richness of communities (in 0.5-m2 plots), and the numbers of adventive and indigenous species (in 15-m2 plots). The field data have been processes by methods of ordinary and multivariate regression analysis. The results show that variation in saturation with adventive species between small areas of herbaceous communities largely depends on the number of such species in larger areas, their species-holding capacity, and the level of completeness of communities.  相似文献   

17.
当前有关流域生态补偿的研究和实践探索,均倾向于从责任分配视角来设定流域生态补偿的适用条件。然而,从责任分配视角来界定流域生态补偿之适用条件面临着诸多困境。以水质控制目标作为适用条件的地方立法和以超过Ⅲ类水质标准作为流域生态补偿适用条件之观点,均限缩了流域生态补偿的适用范围,导致了补偿义务主体与受偿主体之间法律关系的混乱,并背离了流域生态补偿的本质和基本功能预设。无论从流域生态补偿的功能定位出发,还是基于该制度构建的正当性基础和可行性考量,均应从权利确认而非责任分配视角来明晰流域生态补偿之适用条件。首先,流域生态补偿的基本功能是流域生态利益正向供给激励,受偿主体的权利确认与保障是这一制度构建的重心。从责任分配的角度来界定流域生态补偿之适用条件,将导致其基本功能的偏离;其次,"最少受惠者的最大利益"原则是流域生态补偿制度构建的正当性基础,流域生态补偿的本质是对"最少受惠者"发展权的弥补。从责任分配视角界定流域生态补偿之适用条件遮蔽了流域生态补偿法律关系中的"最少受惠者";再次,受益主体的非特定性意味着从权利确认视角来界定流域生态补偿之适用条件将更具有可行性。从权利确认视角来看,流域生态补偿的适用条件应包括:有生态增益行为、非有责主体、不问主观动机与现实损害后果。  相似文献   

18.
Water tables are strictly controlled throughout much of the Netherlands. Higher water tables could permit the restoration of wetland ecosystems. Deriving benefits from this requires the spatial matching of physical planning, eco-hydrological processes, and economic activities. This paper reports on a study combining spatial analysis and disciplinary integration to assess management strategies for the Vecht river basin in the Netherlands. The paper addresses two research questions. How can the information generated by spatial models be condensed into performance indicators for the evaluation of strategies? How can spatial information be retained in the evaluation, and does this lead to different rankings and/or insights? Procedures for the construction of performance indicators for three criteria – net present value, environmental quality and spatial equity – are presented. The evaluation concludes that recreation and higher water tables provide a means for restoration, recouping of costs, and stimulating regional incomes. Maintenance of spatial detail led to different insights, and in particular indicated uncertainty about this conclusion.  相似文献   

19.
Ecological scales proposed by H. Ellenberg, E. Landolt, and D.N. Tsyganov have been used to evaluate the roles of three ecological factors—elevation above sea level, soil moisture, and soil nitrogen—in determining the composition of forest communities in the Southern Ural region. The results obtained with all these scales are similar, which indicates that any of them can serve the purpose.  相似文献   

20.
In order to support authorised discharges of low level radioactive liquid effluent into coastal regions, mathematical models are required to robustly predict radiological impacts on critical groups of current and proposed changes to liquid discharges. The grid model presented here simulates the long term dispersion and transport of radioactivity discharged from the Sellafield site in Cumbria, UK, and the subsequent exposure of critical groups in Cumbria and across the Irish Sea in Northern Ireland. The fine grid of the model allows a good resolution of the seabed sediment distribution. This benefits the predictions for the last decades of low discharge level, when bed sediment can become a source of contamination by bringing back the legacy of past high discharges. This is highlighted by the dose comparison, where the predicted dose to Cumbria critical group follows well the dose estimated from environmental data during the low discharge level period.  相似文献   

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