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1.
Abstract

Many relict and endemic legumes are often rare and endangered species, located in remote and almost impenetrable areas. This makes it difficult to study their symbiosis with nodule bacteria. The aim of this work was to obtain root nodules under laboratory conditions of Hedysarum zundukii, Oxytropis popoviana, Oxytropis triphylla, Oxytropis tragacanthoides, Astragalus chorinensis and Glycyrrhiza uralensis belonging to the Miocene-Pliocene relicts, usually growing in restricted habitats of the Baikal Lake region. A pot experiment was conducted with soils and seeds collected in distribution areas of these legumes. The collected soils had low content of N and P, suggesting importance of nitrogen-fixing symbiosis for successful maintenance of plant populations. The symbiotic nodules were observed on roots of all plant species tested and 52 bacterial strains assumed as root nodule bacteria (rhizobia) were isolated from nodules. The proposed method avoids collection of native plants and prevents decrease in plant populations. The isolated bacteria will be used to search for ancestral genes responsible for the specificity and efficiency of rhizobia-legume symbiosis and can contribute to the conservation of rare and endangered species of relict legumes in the Baikal region.  相似文献   

2.
Recent urban ecological research shows high species numbers in slowly developed cities and towns. Urban development is known to fragment, change and weaken urban biodiversity. Conservation areas have been the main tool in protecting threatened species both in rural and urban municipalities in Finland. However, very little is known about how successful conservation areas are in protecting rare and threatened species and their habitats in boreal cities and towns. Helsinki, the capital of Finland, is a rapidly urbanising hemiboreal city, which has a high number of vascular plant species in both native and urban biotopes. One and 0.25 km2 grid square maps and simple overlay methods are being used to analyse data on species occurrence and land use. Total species number, a rarity index and historical and threatened groupings are used to classify species and their habitats. At present, conservation areas can protect only a small proportion of threatened species in Helsinki. More protection areas, green areas in future land-use decisions and new management goals are needed to protect the biodiversity of existing vascular plant species.  相似文献   

3.
Species distribution models have recently become important tools in ecological research. Prediction of suitable habitats for threatened and endangered species is essential for the conservation and management of their native habitats. A landscape scale approach is relevant for biodiversity conservation since landscape planning and management are generally conducted at wide spatial scales, focusing on areas with complex landscape configuration as a consequence of human activities. The aims of this study were to test a maximum entropy approach (Maxent) to the development of a niche-based model for species of conservation interest and to relate this model to landscape structure metrics. The results obtained here showed a good predictive power of Maxent for the three target species and highlighted the importance of landscape structure analysis for the detection of patterns of habitat suitability. Moreover, this work stressed that combining classical environmental information with landscape structure in analysing habitat suitability for species of conservation interest may be used to guide conservation efforts and landscape management practices.  相似文献   

4.
ABSTRACT

Where conservation evolves in contentious political contexts, it can be framed by competing priorities reflecting collective remembering, cultural politics and identities intertwined with the symbolic representation of the built environment. Ireland provides a unique lens to examine these themes as the only western European country to experience colonial domination, which forms a key aspect of the context for the evolution of conservation policy and practice. The aim of this paper is to chart the shifting representations of built heritage in Ireland, and their relevance in the emergence of conservation and heritage policy, set in the context of broader social, political and economic change over time. This is achieved, firstly, by a review of secondary source material to identify key events, eras and trends. Discourses of heritage are then examined in debates of the Oireachtas (the Irish legislature), identifying tensions around the emergence of conservation in a historic environment largely associated with colonial power and identity. These shifting discourses are then related to policy evolution, particularly the late adoption of a legislative framework for conservation (in 1999). Finally, conclusions are developed to identify wider lessons from the production of urban conservation priorities in the context of contested heritage.  相似文献   

5.
Abstract

The paper presents research in eco-coenotic features of cryopetrophyte communities of the Osevoi Ridge in the Western Sayan Mts. All communities studied are in the association Saxifrago oppositifoliaeRhodioletum quadrifidae. This association includes all communities with a predominance of alpine and arctalpine petrophytes, which are largely facultative and obligate calciphile plants. The coenoflora of the association Saxifrago oppositifoliaeRhodioletum quadrifidae is represented by 54 species of higher vascular plants. The dominant species in its structure are those of Holarctic distribution and species generally confined to the Altai-Sayan mountain region, with Papaver pseudocanescens, Poa smirnowii, Sajanella monstrosa, Saussurea foliosa and Saxifraga melaleuca being endemics. In the structure of the belt-zonal groups, arctalpine and alpine species dominate. Among ecological groups, obligate and facultative petrophytes, generally cryophytes, are dominant. The predominance of some particular belt-zonal and ecological groups of species indicates greater specificity of the environmental conditions in which the communities were formed and are currently being formed.  相似文献   

6.
Abstract

This article describes the results of studying the Culicidae species composition in Tomsk region, during 8 years, 2008–2015. The survey revealed 31 mosquito species of five genera, namely Anopheles, Culex, Culiseta, Coquillettidia, Aedes. Dominant, numerous, common and rare species of Aedes genus were detected. The complete list of Culicidae species in Tomsk region was recorded. Ae. annulipes and Ae. sticticus were included in the species composition of Siberia; their presence in Tomsk region had previously been doubted. Some other species were deleted from the list because they were absent at the present time.  相似文献   

7.
Abstract

Sphagnum mosses are a characteristic component of plant communities in the mountain mires of the Altai-Sayan region. The genus Sphagnum L. ranks first in the species diversity and includes 32 species, accounting for 57.1% of the species diversity of sphagnum mosses of Russia and 62.8% of the species diversity of sphagnum mosses of the Asian part of Russia. Twenty-five species of sphagnum moss are revealed in the mires of the Western Sayan and Altai, listed in this paper; 28 species occur on the Kuznetsky Alatau mires. Rare species are Sphagnum aongstroemii, S. auriculatum, S. contortum, S. platyphyllum, S. pulchrum, S. subfulvum, S. tenellum.  相似文献   

8.
《住房,理论和社会》2012,29(4):211-225

It is technically possible to decrease the Danish fossil fuel consumption by 50 % within less than 20 years, without a decrease in the material standard of living and without nuclear power. Although Denmark followed an active and internationally praised energy policy, 1987 will probably see a Danish record in fossil fuel consumption, beating the old record from before the first energy crisis in 1973. Nevertheless there has been some success in developing conservation methods and renewable energy technologies like wind power and biogas—based village energy plants—and therefore it now seems technically possible to initiate a strategy for reduced consumption of fossil fuels. The present sectorized and centralized organization of energy systems makes the supply side based on fossil fuels dominate over consumer‐oriented conservation technologies blocking effective conservation strategies. It is therefore necessary to regionalize and decentralize the energy systems in order to synchronize conservation, supply‐side energy efficiency and renewable energy use, and in that way effectively reduce the consumption of fossil fuel.  相似文献   

9.
《Urban Water Journal》2013,10(5):334-342
ABSTRACT

This study applies an integrated approach to investigate public perception of residential water issues during a period of economic crisis. The study investigates the perceptions and practices of Athenians in water conservation, their satisfaction with the supplied water, their opinion on the privatization of Water Company and their willingness for additional payment for the improvement of water services. A survey was conducted using a structured questionnaire. Results indicate that the respondents have adopted water conservation practices, but there is still room for further saving. Most of the respondents declared to be satisfied with the supplied water and do not agree to the privatization of water companies. Women, older participants and those having lower income are less willing for additional payment. Research findings are useful tool for policymakers to design policies and make decisions regarding water management, ownership of water companies and changes in behavior of water use.  相似文献   

10.
ABSTRACT

The following five species are described as new to science: Inostemma muelleri sp. n., Metaclisis iranica sp. n., Platygaster curvistriata sp. n., Platygaster nepalica sp. n. and Prosynopeas antoni sp. n. The type material of Metaclisis ocalea (Walker) is described, and M. ocalea (Walker) and M. montagnei Maneval are synonymised with M. areolata (Haliday).  相似文献   

11.
Abstract

This article reports the species richness of vascular plants in the young fluvioglacial landscapes in the Severo-Chuiskiy centre of present-day glaciation using the example of the fluvioglacial deposits of the mountain-glacial basin Aktru. These landscapes are four well distinguished classes of habitats: open pebble fields with minimal vegetation, young larch forests on elevated parts of the relief, shrub thickets on the banks of the Aktru river, and sites with ground-frazil near the valley slopes. There are 132 species of vascular plants in the young fluvioglacial landscapes. These include 36 families and 77 genera. There are 3 species of pteridophytes (only Equisetum), 4 species of gymnosperms, and 125 species of angiosperms. The highest species diversity was recorded for Asteraceae, Poaceae and Salicaceae families, and for Salix, Poa, and Carex genera. The highest species richness – 100 species – were recorded for open pebble fields. There were 76 species in the young larch forests, and 58 species occurred in shrub thickets. The lowest richness is characterised for the sites with ground frazil, where 31 species were recorded.  相似文献   

12.
F.  A.  Y. R.  N. 《Landscape and urban planning》2004,67(1-4):195
Understanding the dynamics of biodiversity in changing agricultural landscapes is a goal for nature conservation and agricultural policies. Agriculture operates at several spatio-temporal levels from field to landscape, and induces differential response of communities according to their ecological traits. Reactions of several taxa to landscape and agricultural changes was conducted along landscape gradients in northern Brittany (France) gathering 14 sites. Landscapes ranged from fine grained areas, with a large proportion of permanent grasslands, wood and hedgerows, to coarse grained ones dominated by crops. Response of communities were either loss of species along the gradient (as for Diptera Chironomidae and Empididae), replacement (Coleoptera Carabidae) and no change in species composition (small mammals). In this paper, we present why these taxa react in such different ways according to their life history traits, their mobility patterns and to which parameters of landscape structure or agriculture intensification they are sensitive. Density of hedgerow networks, and permeability of individual hedgerows determine the spatial distribution of adults Diptera according to their flying ability. Mean body size of carabid beetles significantly decreases along the gradient of agricultural intensification, small species adapted to disturbance replacing large ones that are characteristic of stable habitats. The same small mammal species are found all along the two gradients, but their relative abundance is linked to the importance of crops versus more stable habitats in the landscape.We concluded that species survival in those fine grained agricultural landscapes depends on processes operating at the site scale and defining habitat quality, and processes operating at the landscape and/or metapopulation scale such as landscape modifications in connectivity and habitat availability.  相似文献   

13.
Problem, research strategy, and findings: Regional conservation initiatives struggle to meet funding needs when complying with the Endangered Species Act (ESA) of 1996 and need money early to pay for required planning and to acquire land to mitigate the impact of development. Transportation agencies struggle to comply with the ESA and have increasingly been willing to fund regional habitat conservation plans (RHCPs) to do so. We review documents from 22 RHCPs and interview representatives of 16 RHCPs to understand how transportation agencies have contributed to funding RHCPs. We find that transportation agencies mitigate their impacts and provide early and consistent financing to facilitate the planning process, help RHCPs establish initial conservation preserves, and allow RHCPs to capitalize on lower land prices during downturns in the development market. We only sample RHCPs in a few states, however, and these examples may not comply with laws in others. Many of the cases studied are recent; time is needed to assess their long-term success. We recommend further study to assess applications to sectors beyond transportation and beyond the areas we studied.

Takeaway for practice: Transportation agencies have struggled to meet environmental requirements and habitat conservation agencies have typically considered transportation agencies threats to the environment. Where adversarial relationships can be overcome, partnerships between transportation and conservation programs can effectively finance habitat conservation while facilitating capital investments in transportation systems.  相似文献   


14.
Abstract

The paper contains a complete annotated list of freshwater ichthyofauna of the Middle Ob River basin. The list is based on an analysis of publications and on the results of the authors’ research, and it includes 43 species in two classes, 9 orders, 12 families, and 30 genera. Ten of all listed species are introduced and only seven are naturalized. For each species, taxonomic comments are provided where necessary and conservation status, distribution within the Middle Ob River basin, abundance and commercial value are indicated. Latin and English names are given.  相似文献   

15.
Abstract

The paper presents data on the pollination ecology and seed production of three Pedicularis L. species in the high mountains of Altai. It was determined that the investigated species are highly specialised entomophiles. Specialisation to entomophily is expressed in a number of adaptations: the presence of nectar in flowers of Pedicularis, pollen and secondary attractants (visual and tactile) that attract insects, as well as specific morphological structures which facilitate the process of pollen hitting a certain area of the body of the insect. Hercogamy and protogyny and gradual explication of the flowers in the inflorescence and their long lifespan in wide ranges of temperature and humidity are also adaptations to cross-pollination. The investigated species have high fertility and viability of the pollen grains. Seed production ranges from 57.1 to 261.3 seeds per stem. The seeds have organic rest. Promoting agents of seeds germination of the investigated species are cold stratification in conjunction with the gibberellic acid treatment. The biology of louseworts is peculiar because they combine autotrophic feeding with parasitism on other higher plants. The lack of strict species specificity in the choice of host plants was discovered. The complex of host plants includes 27 species.  相似文献   

16.
ABSTRACT

Agriculture and forestry resources are central to African development. In this study, Tokpli mining zone (Togo) soils were characterised and the ones appropriate to garden crops and reforested species identified and located on a map using several database and literature. Results showed that tomato (Solanum Lycopersicum) and chilli pepper (Capsicum annuum) are suitable for slightly acidic clay soils of Ahlimegni. Abelmoschus esculentus is suitable for Assou-kondji soil. Solanum macrocarpon was found appropriate to Ziome-kondji and Anagonou-kpota soils. Forest species such as Salix babylonica, Khaya senegalensis, Eucalyptus spp., and Terminalia superba exhibited best growth on slightly acidic clay soils of Ahlimegni area, rich in organic matter. Acacia auriculiformis, Azadirachta indica, Cola gigantea, and Albizia zigya can grow better on the slightly basic sandy soils of Anagonou-kpota and Ziome-kondji. Other species like Gmelina arborea, Mangifera indica, Salix babylonica, and Morinda lucida were found not selective and could be reforested on all soil types.  相似文献   

17.
18.
Nineteen waterways in the German lowlands were surveyed between 1992 and 1997 to evaluate their fishes conservation capacity. From 277 sites a total of 84 821 fish of 31 species was collected. Number of species in various waterways ranged from 6 to 26 with a mean±standarddeviation of 15.4±5.4. Mean species diversity was H′=1.61±0.29 (range 1.02–2.20), and corresponding evenness 0.61±0.09 (0.51–0.76). Fish communities of waterways were dominated by perch and roach, both contributing in mean 68.5±12.5% to the total catch. The mean relative abundance of threatened fish listed in “Red Data Books” of Germany or Europe was 7.83±4.82%.Percentage of artificial shoreline structures like riprap or sheet pile wall was inversely correlated to species number, species diversity and abundance of intolerant species. This study was a first approach to estimate the percentage of habitat restoration required to increase species diversity. Even the restoration of one-fifth of the river banks, the restoration of natural shoreline structures from close 0 to 20% of the bankline should result in substantial improvement of fish diversity, and significantly contribute to species conservation and persistence of viable populations of threatened fishes in waterways. In regard to such relatively low restoration effort, biodiversity conservation in waterways is compatible with long-term resource use, navigation and human needs. Even though heavily modified, waterways are also recommended for conservation issues by their large area covered as well as their substantial number of fish species.  相似文献   

19.
Sinarundinaria alpina is a species of mountain bamboo which is a source of various conflicts between the managers of the Kahuzi-Biega National Park (KBNP) and surrounding communities. This mountainous species is threatened by these communities to meet their need for various uses. Six permanent plots of 3 hectares were set between 2000–3000 metres above sea level and floristic inventories were made. In addition, information related to anthropogenic threats related to bamboo exploitation was recorded. All data were analysed using quantitative statistical parameters. Results suggest the existence of 196 species in these six permanent plots of the group Bamboo. The position of this Sinarundinaria alpina vegetation in the dynamic rainforest recovery dynamics is confirmed by the presence of trees and tree-nurseries of these trees. Fifty-three species, 27% of the plants observed, including Sinarundinaria alpina seedlings, contribute to the daily feeding of great apes, mainly Grauer’s Gorilla (Gorilla beringei graueri). This forest appears to be one of their critical habitats. The decrease in the area covered by bamboos is due primarily to anthropogenic activities but also some natural hazards (expansion of Sericostachys scandens, natural fading of Bamboo and attacks by beetles). Following these findings, conservation strategies were proposed. Several strengths were noted, including multiplication of bamboo nurseries and distribution of seedlings to local communities. This can be seen as a strong development of this sector in the future. This study is a preliminary assessment for further investigation.  相似文献   

20.
Abstract

The study was conducted during 2004–2015 in West Siberia natural forests. The Tomsk region mycobiota is almost unstudied though this region is considered to be an accumulation zone for North American, European, and Far East fungi species. Sampling was implemented in pure cedar or pine stands. Molecular data and microscoping identified 283 macromycetes species, which form ectomycorrhizas with Pinus sibirica and Pinus sylvestris.  相似文献   

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