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1.
Eight strains of bacteria capable of degrading polycyclic aromatic hydrocarbons have been isolated from soils and bottom sediments sampled in the region of Verkhnekamskoe potash deposit (Berezniki, Perm krai) and classified with the genus Arthrobacter on the basis of phylogenetic analysis (16S rRNA genes) and morphological and chemotaxonomic characters. According to the results of 16S rDNA sequence alignment, strains B905, SMB11, SMB145, SF27, and DF14 show the highest sequence homology to the type strain of A. crystallopoietes (99.7%), and strain SN17, to the type strain of A. arilaitensis (99.8%). The isolated strains are capable of growing on naphthalene and phenanthrene (as the sole sources of carbon and energy) in the presence of 60 mg/l NaCl. Their cells contain large plasmids ranging in size from 85 to 130 kb. Plasmid elimination from Arthrobacter sp. SF27 has proved to result in the loss of capacity for growing on naphthalene and phenanthrene, suggesting a plasmid localization of genes responsible for degradation of these compounds.  相似文献   

2.
Objectives and methods of mapping the ecological state of the plant cover at different spatial levels—federal, regional, and local—are analyzed. The maps used as examples are as follows: at the federal level, “Ecological State of Rangelands in Russia” (1:10 000 000); at the regional level, “Vegetation of Moscow Oblast” (1:200 000); and at the local level, “Vegetation of Narofominskii Raion” and “Current State of the Plant Cover in Narofominskii Raion” (1:50 000).  相似文献   

3.
The analysis of palaeoenvironmental archives—sediments, archaeological remains, tree-rings, documents and instrumental records—is presented as a key element in the global scientific endeavour aimed at understanding human–environment interactions at the present day and in the future. The paper explains the need for the focus on palaeoenvironmental studies as a means of ‘learning from the past’, and presents the rationale and structure of the IGBP-PAGES Focus 5 programme ‘Past Ecosystem Processes and Human–Environment Interactions’. The past, as described through palaeoenvironmental studies, can yield information about pre-impact states, trajectories of recent change, causation, complex system behaviour, and provide the basis for developing and testing simulation models. Learning from the past in each of these epistemological categories is exemplified with published case-studies.  相似文献   

4.
Efficient protection against global climate change requires international emission reduction measures. Before these ones are decided, the individual states should make arrangements within their own scope of authority for preventing and mitigating the adverse impacts of climate change already in progress as a consequence of carbon dioxide emissions done so far. In spring 2008 Hungary—among the very first ones in the international stage—passed a middle-term National Climate Change Strategy, which determines both the national tasks in order to reduce greenhouse gas emissions, and sectoral tasks of the adaptation to the ongoing climate change for the period of 2008–2025. As a concrete case study we investigated the possible impacts of the regional change in atmospheric carbon dioxide concentration, temperature and precipitation conditions of the Carpathian Basin on the cultivation conditions of maize, based on the downscaled IPCC 2007 scenarios. Temperatures of each scenarios increased significantly to basic run (1961–1990). This change suppressed the positive influence of elevated CO2 on carbon assimilation. Serious depression may be waited during extreme hot days at Keszthely, Hungary.  相似文献   

5.
Forest income and dependency in lowland Bolivia   总被引:1,自引:0,他引:1  
Forests contribute to livelihoods of rural people throughout the tropics. This paper adds to the emerging body of quantitative knowledge on absolute and relative economic importance, through both cash and subsistence income, of moist forests to households. Qualitative contextual information was collected in six villages in lowland Bolivia, followed by a structured survey of randomly selected households (n = 118) that included four quarterly income surveys. We employed a novel data collection approach that allows detailed estimation of total household accounts, including sources of forest income. We estimated the average forest income share of total annual household income (forest dependency) at 20%, ranging from 18 to 24%. Adding environmental income increased the average to 26%, being fairly constant across income quartiles at 24–28%. Absolute levels of forest income increased with total household income, while forest dependency was the highest in the best-off income quartile—the primary harvesters of forest products are better-off households. The pattern of high forest dependency among better-off households has also been reported from other countries, indicating that this pattern may be more common than advocated by conventional wisdom. Using ordinary least squares (OLS) regressions, we found significant determinants of absolute forest income to be household size, sex of household head and area of cultivated land; the significant determinants for forest dependency were level of education, whether household head was born in village and whether household was food self-sufficient. Better-off households were able to realise cash income from forests, while poorer households—in particular if headed by women—were more reliant on subsistence forest income. We argue that the differential patterns of forest income across income quartiles should be considered in future development interventions and that findings indicate a potential for forests to contribute to moving households out of poverty.  相似文献   

6.
Some specific features of the distribution of resident Chiroptera (10 forms) in the eastern East European Plain and adjacent areas (44°–65° N, 40°–60° E) are described. It is noted that in different seasons of the year,Myotis dasycneme, M. daubentonii, M. nattereri, M. mystacinus, M. brandtii, Plecotus auritus, Eptesicus nilssoni, andE. serotinus serotinus are found more often in upland areas with karst and other erosional forms of relief, whereasE. serotinus turcomanus andPipistrellus kuhlii display no preference for these types of relief.  相似文献   

7.
Comparative allozyme analysis of 26 marginal island populations of Pinus sylvestris L. and 20 populations from the center of the species range has confirmed, at the species level, the Wright-Dubinin “island model” of automatic genetic processes and Mayr’s hypothesis about homozygotization of small isolated populations at range boundaries. It has been shown that the polymorphism of isolated populations sharply decreases when their area is reduced below 15–20 km2 and increases to the level observed in the center of the range when the population area exceeds 50–100 km2. A chorogenetic classification of marginal P. sylvestris populations is proposed.  相似文献   

8.
Climate change adaptation in European river basins   总被引:1,自引:1,他引:0  
This paper contains an assessment and standardized comparative analysis of the current water management regimes in four case-studies in three European river basins: the Hungarian part of the Upper Tisza, the Ukrainian part of the Upper Tisza (also called Zacarpathian Tisza), Alentejo Region (including the Alqueva Reservoir) in the Lower Guadiana in Portugal, and Rivierenland in the Netherlands. The analysis comprises several regime elements considered to be important in adaptive and integrated water management: agency, awareness raising and education, type of governance and cooperation structures, information management and—exchange, policy development and—implementation, risk management, and finances and cost recovery. This comparative analysis has an explorative character intended to identify general patterns in adaptive and integrated water management and to determine its role in coping with the impacts of climate change on floods and droughts. The results show that there is a strong interdependence of the elements within a water management regime, and as such this interdependence is a stabilizing factor in current management regimes. For example, this research provides evidence that a lack of joint/participative knowledge is an important obstacle for cooperation, or vice versa. We argue that there is a two-way relationship between information management and collaboration. Moreover, this research suggests that bottom-up governance is not a straightforward solution to water management problems in large-scale, complex, multiple-use systems, such as river basins. Instead, all the regimes being analyzed are in a process of finding a balance between bottom-up and top–down governance. Finally, this research shows that in a basin where one type of extreme is dominant—like droughts in the Alentejo (Portugal) and floods in Rivierenland (Netherlands)—the potential impacts of other extremes are somehow ignored or not perceived with the urgency they might deserve.  相似文献   

9.
The purpose of the present work is to asses the possibility of detecting changes in soil organic carbon (SOC) at the end of the 5-years of the first Commitment Period (CP) of the Kyoto Protocol of the United Nation’s Framework Convention on Climate Change (1 January, 2008–31 December, 2012), by both direct measurement and the use of an opportunely evaluated SOC model, CENTURY. The investigated soil is young, developed since 28 years on virtually C-free spoil banks and under the influence of two managed forest stands, one a mix of English oak (Quercus robur L.) and Italian alder (Alnus cordata Loisel.) and the other pure English oak. The SOC stock of either stand was monitored since the time the stands were planted in 1981, and it was used together with other parameters for the model evaluation, while the future projections for the end of the first (2012) and second (2017) CP were made according to two extreme IPCC climatic scenarios: A1F1, the most dramatic, and B2, among the less impacting. Direct SOC measurements performed at the beginning and at the end of a time frame equivalent to a commitment period (2004–2008) had not shown significant variations in either stands. Compared to the 2008 SOC stock, in both stands the model shows variations at the end of the first CP from 0.7 to 1.8 Mg C ha−1 for the A1F1 scenario and from 0.3 to 1.7 Mg C ha−1 for the B2. These variations are within the standard deviations of the C stocks measured in 2008. On the contrary, at the end of the second CP, the modelled SOC increments range from 2.5 to 3.6 Mg C ha−1 (A1F1) or from 1.9 to 3.4 Mg C ha−1 (B2), indicating the possibility to detect the SOC changes by direct measurement, since the values well agree with the minimum detectable variation estimated for both sites in 3.3–4.5 Mg C ha−1. This work shows that SOC stock changes measured directly in the field can be minimal at the end of both CPs, and that CENTURY well simulates the SOC dynamics of the stands. The use of such a model, validated at long-term experimental sites, hence represents an effective tool for estimating future changes in SOC amounts in support of direct measurements when a short period of time, such as the CP, is considered.  相似文献   

10.
The surface sediments of Vembanad Lake, a tropical estuary on the west coast of India, were analyzed for carbon (TC, TOC, TIC), nitrogen (TN), amino acids and two amino sugars. C/N ratios for the surface sediments vary from 1.0–21.8, indicating terrestrial sources of organic matter. Various biogeochemical indicators based on amino acids such as Asp/β-ala and Glu/γ-aba ratios revealed that the organic matter in the 5- to 10-cm surface sediments was fresh and had not undergone extensive degradation. However, the Gluam/Galam ratio for surface sediments of Vembanad Lake varies from 0.4–2.1, indicating the dominance of bacterial biomass in the sediments. Organic matter in the sediments was found to be highly reactive, with a reactivity index ranging from 2.4–7.4, suggesting rapid remineralization. Electronic Publication  相似文献   

11.
This paper presents the technical aspects of a new methodology for assessing the susceptibility of society to drought. The methodology consists of a combination of inference modelling and fuzzy logic applications. Four steps are followed: (1) model input variables are selected—these variables reflect the main factors influencing susceptibility in a social group, population or region, (2) fuzzification—the uncertainties of the input variables are made explicit by representing them as ‘fuzzy membership functions’, (3) inference modelling—the input variables are used to construct a model made up of linguistic rules, and (4) defuzzification—results from the model in linguistic form are translated into numerical form, also through the use of fuzzy membership functions. The disadvantages and advantages of this methodology became apparent when it was applied to the assessment of susceptibility from three disciplinary perspectives: Disadvantages include the difficulty in validating results and the subjectivity involved with specifying fuzzy membership functions and the rules of the inference model. Advantages of the methodology are its transparency, because all model assumptions have to be made explicit in the form of inference rules; its flexibility, in that informal and expert knowledge can be incorporated through ‘fuzzy membership functions’ and through the rules in the inference model; and its versatility, since numerical data can be converted to linguistic statements and vice versa through the procedures of ‘fuzzification’ and ‘defuzzification’.  相似文献   

12.
On the basis of abundant fossil and subfossil bone remains, the ecological and faunal role of the narrow-skulled vole in zonal rodent communities of northern Eurasia is analyzed over the period from the Late Pleistocene to the present time. Special attention is given to the correlated dynamics of relative abundance of Microtus gregalis and other rodent species in the course of transition from one zonal type to another and to specific features of this correlation in the southern, middle, and northern parts of the species range. It is shown that distinctive dimensional and morphotypic features of the two currently existing subspecies, Microtus gregalis major Ogn. and M. g. gregalis Pall., are the product of concordant development of the species and environmental conditions in the past 3000–4000 years (transition from the Holocene optimum to the present-day climate and state of the natural environment). Published in Russian in Ekologiya, 2007, Vol. 38, No. 2, pp. 117–123. The article was translated by the authors.  相似文献   

13.
Analyzing different pathways by which social–ecological systems can loose resilience and enter trajectories of collapse constitutes an important aspect of our quest towards understanding resource sustainability. This paper’s goal was to better understand the effect of a particular class of disturbance—the accumulative effects of routine stressors—in the context of marine social–ecological systems. To that effect, we built a system dynamics model using empirically collected institutional and biological field data of an artisanal fishery in the Gulf of California, Mexico. Among our findings, we identified different scenarios under which even very small endogenous changes in the relationship between ecological and institutional variables can send a seemingly resilient system into a trajectory of collapse. We discuss why these types of disturbances are so difficult to prevent and be identified by the users of the resource, as well as potential strategies to address these challenges.  相似文献   

14.
The mid altitudinal oak, Quercus floribunda forms predominantly evergreen forest in Central Himalaya between 2000–2400 m. It is late successional, mature phase species that has limited regeneration on disturbance prone sites. This oak produces mast seed crops at an interval of 2–3 years. During masting in Q. floribunda the seed fall and germination is upto ten times greater than in normal years, emphasizing the importance of mast year crop in forest maintenance. However, no mast year in this species since the last nine years (1997–2005) is a matter of serious concern. The rise in the summer and winter temperature over a period of 15 years appear to have affected the frequency of masting in this oak. The importance of masting can be adjudged from the fact that 97% of the surviving seedlings m−2 are of the mast year crop.  相似文献   

15.
Long-term (1985–1999) stationary observations on a polymorphic population of northern mole voles (Ellobius talpinus Pall.) in Kurgan oblast, Russia, using a mark-recapture method yielded original data on the population dynamics and population structure of a polymorphic colony consisting of animals of three color morphs (black, brown, and intermediate or transitional). The period when the northern mole vole population dynamics was studied (15 years) consisted of five distinct three-year population phases: depression, growth, peak (stabilization), decline to depression, and the next growth phase. It was shown that the population dynamics and changes in the population structure of northern mole voles in the Kurtamysh colony are cyclic.  相似文献   

16.
Variations in breeding success of the Whiskered Terns (Chlidonias hybrida) were studied in two wetlands; Anzali (2005 and 2008) and Zarivar (2007–2008) in north and west Iran. Nesting success was modeled and compared using information-theoretic approach implemented in program Mark in order to assess effects of colony locations, years and nest initiation dates on the probability of daily nest survival. Clutch size did not vary between colonies and years. Breeding success varied between colonies (Zarivar > Anzali), and years only in Anzali (2005 > 2008). Overall daily nest survival was 0.977. (95% LCI 0.973, UCI 0.981), equivalent to a Mayfield nest survival of 0.317. (95% LCI 0.255, UCI 0.387). Egg-laying periods and colony site were important covariates affecting the daily survival rates (Σω i = 0.86 and Σω i = 0.83, respectively), while, the support for the effect of year was less (Σω i = 0.41). We concluded that Lake Zarivar provides a more favorable nesting location for Whiskered Terns probably because of little changes in rainfall and water depth during the breeding seasons which influence breeding performance.  相似文献   

17.
Fuelwood is the only important source of energy in the mountainous region of the Garhwal Himalaya, India. Since the commercial source of energy is generally beyond the reach of ordinary people due to their poor socio-economic conditions and due to limited supply and lack of communication facilities for transport of LPG, the villages of the inner region of the Garhwal Himalaya depend on their fuel requirement from the forest. In the present study, two villages of the Nanda Devi Biosphere Reserve in Uttarakhand part of the Indian Himalaya i.e. Lata and Dunagiri located at 2,415 and 3,600 m altitudes, respectively, were selected for the study of socio-economic profile and vegetation and for estimation of per capita fuelwood consumption and the degree of disturbance. The study was conducted from 2002–2005. The population of these villages is migratory and belongs to the Bhotiya community, a scheduled tribe consisting of two subgroups known as Tolcha and Marchha. They grow traditional crops as well as cash crops. Important tree species used for fuelwood include Cedrus deodara, Pinus wallichiana, Cupressus torulosa, Taxus wallichiana, Acer indicum, Quercus dilatata and Viburnum cotinifolium. Maximum density among trees was shown by Pinus wallichiana (169.6 trees ha−1) in village Lata and by Cedrus deodara (89.6 trees ha−1) in village Dunagiri. The average per capita consumption of fuelwood in villages Lata and Dunagiri was 4.03 and 4.77 kg capita−1 day−1. Maximum number of trees (29 and 31% lopping for Lata and Dunagiri, respectively) belonged to disturbance class 1 (1–20% lopping) followed by the disturbance class 2 (20–40% lopping). Due to location of these villages in the buffer zone of the biosphere reserve, the fuelwood consumption may cause an adverse impact on the ecological status of this reserve, which urgently requires employing strategies for the conservation and management of this biosphere in terms of fuelwood sustainability e.g. regulation of livestock stock and grazing, using alternative sources of fuels, plantation of multipurpose trees and adoption of ecotourism.  相似文献   

18.
Geographic information system (GIS), remote sensing (RS), gradient analysis, and landscape pattern metrics were coupled to quantitatively characterize the spatiotemporal change of land use and landscape pattern over the period 1988–2007 in a coastal gulf region, southeast China. The results obtained show an increase in cropland, buildup land, and aquiculture area and decrease in orchard, woodland, and beach area during 1988–2007. Landscape fragmented processes were strengthened and landscape pattern structure became more complicated in the last two decades in Luoyuan gulf region. The dynamics intensity of landscape pattern is stronger during 2002–2007 than that during 1988–2002. Spatial difference of urban–rural landscape pattern can be detected distinctively in two transects in terms of landscape metrics. Urbanization processes and the policy developed to transfer seawater into buildup land are two driving forces leading to the spatiotemporal change of landscape pattern in Luoyuan gulf region in the last two decades.  相似文献   

19.
Climate is one of the more complex physical systems in nature, its behaviour being fundamentally non-linear and chaotic. In assessing the potential risks from climate change and the costs of averting it, researchers and policymakers encounter pervasive uncertainty. Sceptics demand to get rid of the inherent uncertainties, and some experts, on the other end, keep sending out messages of catastrophic scenarios hoping that this will increase people’s awareness of the danger we face. The recent admission of a mistake in IPCC’s Climate change 2007 report (promptly broadcast by all the major media groups and newspapers from Jan. 20th 2010 onwards) made by the head of the Intergovernmental Panel on Climate Change—that Himalayan glaciers could melt away by 2035 (the IPCC claim of 2035 is wrong by over 300 years.)—has already brought a damage to the IPCC’s reputation that is likely to be considerable. But in this paper, perhaps risking being provocative and paradoxical, instead of looking for the right answers to what we think are inevitable uncertainties, we intend to search for new questions that may lead to a new way of thinking and may bring about new lifestyles and behaviour for citizens and firms.  相似文献   

20.
Collections made in the course of long-term field studies on ecology of the northern mole vole Ellobius talpinus Pall. in the Ural Region and neighboring areas (more than 2000 individuals from 24 points of the species range) were used to analyze geographic variation in its coat color (color morphs). On the basis of long-term observations (1985–1999) on marked animals from a polymorphic population (Kurtamyshskii raion, Kurgan oblast), the life spans of males and females and the dependence of life span on population density and structure were estimated in animals of different color morphs. Each color morph of E. talpinus was shown to have specific features of the seasonal dynamics of age structure and migrations.  相似文献   

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