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1.
Costa Rica is internationally recognized for its abundant biodiversity and being a leader in the promotion of education strategies for biodiversity conservation. We interviewed staff from 16 institutions developing key environmental communication, education, and participation projects for biodiversity conservation in the country. Through content analysis, hierarchical cluster analysis and Chi-square tests, we examined the characteristics of the projects carried out by these institutions and developed a typology of four categories derived from six variables: primary audience, content, project purpose, location, scale, and facility. Then, we designed a conceptual model describing the integration of conservation and economic development in the educational projects. We found two key approaches related to this integration: vision of nature protection which aims to inform audiences of ecological concepts and focuses on schoolchildren and vision of sustainability which engages adult audiences and is management-oriented. Education for community-based environmental management may serve as a good example of educational projects which integrate conservation and economic development, implementing a vision of sustainability.  相似文献   

2.
Methods of geometric morphometrics and population phenogenetics have been used to evaluate morphogenetic rearrangements in two sympatric species of Myodes voles (M. glareolus Schreb. 1780 and M. rutilus Pall. 1779) from syntopic populations recovering after exposure to local “ecological vacuum” created as a result of rodent extermination in a natural focus of hemorrhagic fever in the southern taiga subzone of the Udmurt Republic. The model used in the study simulates the situation that arises upon nonselective elimination of rodent populations and communities in spring and their subsequent recovery. Analysis of variation in the size and shape of the mandible and in a complex of 30 nonmetric cranial characters has revealed similar (parallel) and species-specific morphogenetic and epigenetic changes occurring during the recovery of local rodent community. Species-specific differences in the pattern of change in the parameter characterizing within-group morphological disparity in the mandible shape (MNND) have been revealed between the dominant species (M. glareolus) and the subdominant species competing with it for territory (M. rutilus). Different reactions of close Myodes species in the course of filling the ecological vacuum are considered as a result of reduction in the level of competition for the subdominant species and a compensatory increase of morphological disparity in the dominant species under conditions of low density and incomplete composition of the community, in accordance with Chernov’s (2005) ecological compensation principle.  相似文献   

3.
Although the coastal salt marshes of Arabian Gulf have been altered extensively by human development activities, there is a paucity of data describing changes in the distribution and abundance of native coastal plant communities. The main objectives of this study are to determine vegetation condition, size structure, and conservation status of Nitraria retusa, a medicinal and salt-tolerant shrub, in disturbed and non-disturbed coastal salt marshes of Kuwait. Size measurements of Nitraria shrubs and nabkas, which are mounds of sediment developed around shrubs, were carried out in 50 quadrats (20 × 20 m2), randomly selected inside and outside Sabah Al-Ahmad Natural Reserve. Species richness and soil properties of nabkas and interspaces, the open areas between the nabkas, were also measured. The results revealed that nabkas of Nitraria in non-disturbed sites are more stable and rich in plant diversity than those in disturbed sites. Mean height and mean canopy diameter of Nitraria shrubs, total plant cover, and species richness are significantly higher in non-disturbed sites than disturbed sites, which indicate the positive influences of conservation for long term on vegetation structure and species richness. The results of soil analyses indicate the important role of nabkas in providing refuges for plant life and species diversity. The present study indicates that more than 50 % of the N. retusa community has been lost during the last few decades. Therefore, N. retusa should be considered an endangered species in Kuwait. The reduction in vegetation cover, a decline in species richness, and the overall degradation of salt marshes are attributed to human development activities along the coast of Kuwait. Effective conservation actions for threatened species in degraded coastal salt marshes of this region include establishment of protective enclosures, prohibitions on development that adversely affects native plant communities, and the planting native salt-tolerant shrubs to facilitate regeneration.  相似文献   

4.
Microbiomes were analyzed in samples of the major soil types of Russia and Western Kazakhstan region from different plant communities (fallow, forest, agrophytocenosis). The representatives of 42 bacterial and 2 archaeal phyla were identified in the samples, among which the dominant positions were occupied by representatives of ten phyla: nine bacterial (Actinobacteria (33.5%), Proteobacteria (28.4%), Acidobacteria (8.3%), Verrucomicrobia (7.7%), Bacteroidetes (4.2%), Chloroflexi (3.0%), Gemmatimonadetes (2.3%), Firmicutes (2.1%), Planctomycetes (2.0%)) and one archaeal Crenarchaeota (2.6%). Data analysis by the methods of multivariate statistics suggests that the taxonomic structure of microbiota is formed under the action of two main factors: the strongest factor is soil acidity, which determines the dynamics of the microbiome at the level of major taxa such as phylum, and the weaker factor is the type of vegetation, which determines the community structure at lower taxonomic level (order, family, genus). Detailed analysis of the samples of podzolic soil in Leningrad Region made it possible to identify bacterial taxa specifically associated both with the type of biome (fallow, forest, agrophytocenosis) and with the specific plant community (specific composition of plant synusia).  相似文献   

5.
While adaptation has received a fair amount of attention in the climate change debate, barriers to adaptation are the focus of a more specific, recent discussion. In this discussion, such barriers are generally treated as having a uniform, negative impact on all actors. However, we argue that the precise nature and impact of such barriers on different actors has so far been largely overlooked. Our study of two drought-prone communities in rural Ethiopia sets out to examine how female- and male-headed households adapt to climate change, particularly focusing on how a variety of barriers influence the choice of adaptation measures to varying extents. To this purpose, we built a conceptual framework based on the Sustainable Livelihood Approach. Data were collected using semi-structured interviews and focus group discussions with male- and female-headed households, community leaders and local extension workers. Our findings suggest that gender-based differences in the choice of adaptation measures at the household level are driven by cultural, social, financial and institutional barriers. Barriers to adaptation—particularly when interacting—have a differentiated impact upon different actors. This outcome hints at the need for donors and policymakers to develop intervention strategies that are sensitive to this fact.  相似文献   

6.
It is shown that the basidiocarps of many wood-decomposing fungi are inhabited by taxonomically and biomorphologically various eukaryotic (Charophyta, Chlorophyta, and Ochrophyta) and prokaryotic (Cyanophyta/Cyanobacteria) algae. They represent widespread eurybiont species and do not include any specialized mycetobionts. The communities formed by them have a host preference and green algae are their basic and obligate component, while other organisms are facultative components. Basidiocarps in which mycetobionts include heterocytic cyanoprokaryotes (Anabaena sp., Calothrix parietina, Hassallia byssoidea, Nostoc commune, N. punctiforme, Nostoc sp., and Scytonema ocellatum) are capable of molecular nitrogen fixation. Its activity is 0.044–0.903 mg of C2H4/m2/h in the basidiocarps of Bjerkandera adusta, Cerrena unicolor, Gloeophyllum sepiarium, and Trametes ochracea and 0.001–0.008 mg of C2H4/m2/h in the basidiocarps of Onnia leporina, Phellinus chrysoloma, Ph. tremulae, and Trametes pubescens. Basidiocarps without algae and those inhabited only by eukaryotic algae have no nitrogenase activity.  相似文献   

7.
Knowledge and knowledge sharing are widely regarded as important assets for the overall performance and competiveness of organizations. This study explored the effect of gender on selected predictors of knowledge sharing behaviors among community-based organizations leaders in the Okavango Delta, Botswana. The study, guided by the patriarchy theory, employed a quasi-experimental research approach, using a counterbalanced design. A sample of 120 subjects, drawn from a cluster sample of 13 villages’ Board of Trustees participating in community-based conservation projects, was used. Data were collected using a retrospective pretest instrument and analyzed using one-way mixed between-within doubly repeated measures ANCOVA. The results revealed that only behavioral intention showed significant effects, F(1, 107) = 6.60, p = .01, suggesting differential effects of gender on intention to share knowledge. The study concluded that females are less likely to share information acquired as part of their portfolio responsibility in the public sphere when compared to their male counterpart.  相似文献   

8.
The topic of carbon sequestration in plants has received much attention recently due to concerns about global climate change, which is being exacerbated by deforestation. In the early days of the global bioenergy boom, the private sector and non-government organizations enthusiastically promoted the planting of Jatropha curcas L. as a key candidate shrub species for the production of bioenergy in West Africa. This study investigates the aboveground biomass production and carbon sequestration potential of J. curcas, which is already widely cultivated for the production of oil seeds, biodiesel and biokerosene. The specific objective is to use a destructive method to develop allometric prediction equations of the aboveground biomass production of J. curcas plantations. 38 J. curcas shrubs were harvested and weighed in order to estimate biomass production. These data were used to develop allometric equations for the estimation of wood, leaf and total aboveground biomass production. The best-fit models found for estimating shrub component biomass and total aboveground biomass production were of the power form. All of the regression equations relating the prediction of leaf biomass, wood biomass and total aboveground biomass with J. curcas diameter at 20 cm above the ground (D) were statistically significant (p < 0.001) and also presented the highest goodness of fit (high R 2). The aboveground biomass carbon content was estimated using the ash method. Carbon content in leaves and wood was, respectively, 48 and 54 %. The current established allometric equations can be helpful to provide a rapid estimation of the aboveground biomass and C stock for J. curcas biofuel projects in semi-arid conditions.  相似文献   

9.
This study was conducted to examine perceptions of the farmers and key informants on the use of low-quality irrigation water for vegetable production in urban and peri-urban areas in Morogoro, Tanzania. The methods used to collect data were farmer surveys (n = 60), focus group discussions (n = 4) and key informants interviews (n = 15). The results showed that the respondents had a positive perception on using low-quality irrigation water for vegetable production. The reported benefits include availability of water throughout the year, highest soil and crop nutrients in irrigation water, less costs of buying commercial fertilizers, vegetable production all year round, sustainable income generation from selling vegetables and also jobs creation in the community among farmers and vegetable sellers. Findings from Mann–Whitney U test and Kruskal–Wallis test score on farmers perception scales indicate an association between the source of low-quality water used and the respondents’ sex. Accordingly, female farmers had higher positive perception on the benefits of low-quality water compared to male farmers. Higher perception score was also observed among farmers who used polluted river water in irrigation vegetable production compared to farmers who used wastewater. Since low-quality irrigation water is a good strategy of coping with scarcity of freshwater for communities which have no alternative source of irrigation water, the study recommends multi-sectorial agencies across the country to be involved in formulating policies and creating health promotion awareness for safe use of low-quality water for benefit maximization and health risk reduction.  相似文献   

10.
Natural resource governance is underpinned by institutions which evolve ‘circumstantially’ over time. An attempt at understanding the contemporary institutions and governance structure of a resource requires an in-depth ethnographic enquiry. Adapting a four-phase institutional analysis framework, this study discusses the evolution and adaptation of wildlife governance structures and institutions using the unique experience of Boabeng–Fiema Monkey Sanctuary in Ghana. The study adopted a transdisciplinary research approach which was participatory and consultative. The key observations are that: wildlife institutions have gone through three main evolutionary phases, a pre-collaborative phase, which was exclusively underpinned by informal institutions; a critical juncture stage, where contextual challenges led to an adaptive response; the third and contemporary phase is a collaborative governance regime, where the erstwhile informal institutions have been complemented by formal state structures and institutions to synergistically enhance viability of the wildlife species. In spite of the problems posed to community members by the monkeys (wildlife), the study still observes a cordial human–wildlife relationship. Based on the study outcomes, we derive four key conclusions which have implications for institutionalism and natural resource governance.  相似文献   

11.
The overgrowing of meadow-bog communities by shrubs and trees (age 5–40 years, crown closure 0.4–0.9) leads to a decrease in incident illumination. As a consequence, juvenile and generative plants disappear from D. incarnata population loci, their average ecological density decreases, and the loci enter the state of regression. The digging activity of wild boars disrupts phytocenotically closed groups of longirhizomatous herbs, thereby creating favorable conditions for seed reproduction of D. incarnata. The species begins to form population loci with a complete ontogenetic spectrum and high ecological density, eventually restoring the normal (definitive) population structure.  相似文献   

12.
Small mammal communities inhabiting natural and anthropogenically transformed areas of the right-bank region of Saratov oblast are fairly similar in species composition. They are represented by wide-spread, common species that, against the background of a low population density of typical steppe species, make a major contribution to the community. The highest ecological tolerance is characteristic of the striped field mouse Apodemus agrarius, which is widespread in the study region and dominates in the majority of natural biotopes and in agrocenoses; the common vole Microtus arvalis is scarce in agrocenoses.  相似文献   

13.
Variation in morphometric parameters of the poorly studied rare species Cephalaria uralensis (Murr.) Schrad. ex Roem. et Schult. has been studied at the northern boundary of its range, in the Southern Urals (Bashkortostan). The species in the region grows in four types of steppe communities of the class Festuco-Brometea. Variation in the majority of parameters is within the species reaction norm. The most variable parameters are the numbers of vegetative and generative shoots and the number of inflorescences per shoot. As shown by discriminant analysis, all 16 cenopopulations included in the study significantly differ from each other (Wilks’ λ = 0.21), with most of them being morphologically and structurally uniform. The state of local C. uralensis appears to be satisfactory, and this species is not at serious risk for extinction in the territory of Bashkortostan.  相似文献   

14.
The structure of genotypic diversity in eight populations of the clonal triploid (2n = 3x = 36) tulip Tulipa riparia inhabiting floodplain communities in the Southern Urals was studied. Analysis of nine polymorphic enzyme systems (ADH, IDH, SkDH, PGI, PGM, FDH, NADHdh, C-EST, GOT) was performed to identify clones. Both monoclonal (D = 0) and polyclonal populations with multiple genotypes from 3 to 12 (D from 0.73 to 0.91) were identified. The polyclonal populations had a high level of heterozygosity. Dispersal of propagules (bulbs) along rivers and even from one bank of a river to the opposite was detected. Some clones disperse along riverbanks to the distance of hundreds meters (up to four kilometres). At the same time, there is an effect of “isolated” or “closed” populations. Almost each sequentially arranged population in one river system have its own set of genotypes. Assessment of the state of the reproductive system components indicates presence of a rare sexual reproduction supporting genetic diversity of T. riparia.  相似文献   

15.
The taxonomic diversity of the Hirudinea fauna and its dependence on the ecological conditions in the Bukhtarma Reservoir (Eastern Kazakhstan) have been studied. The morphological analysis has shown that these leeches belong to two orders and three families: Rhynchobdellida (families Glossiphoniidae and Piscicolidae) and Arhynchobdellida (family Erpobdellidae). On the whole, eight leech species from five genera (Alboglossiphonia, Helobdella, Theromyzon, Piscicola, and Erpobdella) have been identified. Among them, there are three glossiphoniid species (A. heteroclite, H. stagnalis, and T. tessulatum), two species of piscicolids (Piscicola geometra and Piscicola sp.), and three species of predatory leeches (E. octoculata, E. vilnensis, and Erpobdella sp.). Possible effects of hydrochemical parameters of the aquatic environment on the species diversity have been analyzed. Correlation has been revealed between the abundance of species and the physical and chemical characteristics of the environment.  相似文献   

16.
The composition and structure of the Gray mussel (Crenomytilus grayanus) community in Vostok Bay of the Sea of Japan have been studied. A total of 165 species have been identified in the macrobenthos. Its species composition has changed insignificantly since the 1970s. The total biomass of the biocenosis has decreased, and the size-age composition of the C. grayanus population has changed due to poaching. The trophic structure of the community has also changed, with the Shannon indices of species diversity and equitability (E) becoming lower, due to intensive organic pollution of Vostok Bay resulting from increasing recreational activities and sewage discharge.  相似文献   

17.
Increasing rates of deforestation in tropical forests have been linked to agriculturalists. A critical concern generating debate is how well communities of trees recover into a more species rich ecosystem after restoration planting. The aim of the study was to evaluate the pattern of recovery of communities of tree, assess the influence of Acanthus pubescens, Lantana camara and Pennisetum purpureum, on the recovery as well as how restoration planting facilitates recruitment of other native tree seedlings along a gradient of forest restoration in Kibale National Park, Uganda after evictions of illegal settlers. We studied six restoration forests ranging in age from 3 to 16 years, naturally regenerating and three primary forests. Our results showed that recovery with natural regeneration was more effective than restoration planting although the latter enhanced recruitment of other native tree seedling. Tree recovery was generally correlated with age so that species density and diversity increased although at different rates. A reverse pattern was found for dominance but no clear pattern was found for tree density (individual/ha). Communities of tree showed directional patterns of change however community composition were still distinct among the different forests. A. pubescens, L. camara and P. purpureum negatively correlated with species density, tree density and diversity but a positive correlation was found for dominance. Restoration planting can reestablish forests with high species density, tree density and diversity, but this is dependent on age and the extent of the herbs, grasses and shrubs cover in tropical forests.  相似文献   

18.
A view of pollination systems is that they tend to generalization. Here we show that patterns exist in pollination systems that suggest otherwise. We examine how specialization may be affected by latitude, species richness and plant life-forms in 33 plant-pollinator interaction networks. Connectance increases with latitude (P = 0.040), but specialization at the community level significantly declines with increasing latitude, with the strongest evidence in the Northern Hemisphere (P = 0.001). The relationship between specialization level and connectance is negative (P < 0.001). While plants are more specialized in tropical areas and are more generalized at higher latitudes, specialization level also increases with plant richness (P < 0.001), total species richness (P = 0.041) and network size (P = 0.009). Specialization level of life forms of 1129 species differ substantially (P < 0.001), with herbs showing the highest specialization (74%), and tree species the lowest (62%).  相似文献   

19.
A laboratory experiment was performed to evaluate the effect of acrylonitrile (20, 200, and 2000 mg/kg soil) on the abundance and structure of soil microbial community. The results of direct inoculation showed that acrylonitrile at 200 mg/kg stimulated the development of nitrile-utilizing prokaryotes, whereas at 2000 mg/kg it inhibited all test groups of microorganisms, including nitrile- and amide-utilizing bacteria. According to real-time PCR data, representatives of α- and ß-Proteobacteria were the most labile members of the soil microbial community, while Bacteroidetes and Fungi proved to be highly resistant to the effect of the pollutant.  相似文献   

20.
Consideration is given to the examples of suppression of restorative succession by invasive plant species (Solidago canadensis L., Helianthus subcanescens (A. Gray) E. Watson, Impatiens glandulifera Royle) in anthropogenic landscapes of southeastern Belarus. Characteristics of communities blocking the succession process have been revealed: low species richness, dominance of alien species in coverage, high level of synanthropization, and the absence of natural regeneration of trees and shrubs. It is suggested that a delay in succession is caused by the suppressing influence of transformer species on seed germination in apophytic trees.  相似文献   

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