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1.
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   

2.
Many of the problems faced by international projects intending to create adaptive social–ecological systems for climate change stem from lack of stakeholder engagement, limited understanding of local political, economic, and environmental complexities, and restricted time. Local organizations focused on conservation and development might have an advantage in creating adaptive social–ecological systems because they understand local processes and are involved with communities for extended periods of time. A local non-governmental organization, Asociación Ecosistemas Andinos (ECOAN), works in twenty-one communities in the Andean highlands outside of Cusco to conserve the endangered Polylepis forests. As part of the conservation project, ECOAN supports community-led development projects such as building greenhouses. Data for this project were gathered through interviews (with community members in three different communities, ECOAN staff, and donors) and participant observation. This paper shows that ECOAN’s extensive use of participation has led to community ownership of the conservation and development projects. The communities’ close connections to the Polylepis project contribute to resilience through creating networks, extending the local environmental ethic to the Polylepis trees, supporting projects that diversify and strengthen community sustenance, and contributing to the growth of economic activities. This case study provides a positive example of the potential for local organizations and people to take charge of their own resiliency efforts where international projects and protocols may otherwise prove ineffective.  相似文献   

3.
Although knowledge integration and co-production are integral to transdisciplinary approaches to foster sustainable change in social–ecological systems, this type of research is usually not evaluated based on assessments of the learning process. While participants are meant to be central in such approaches, too often, their perspectives are not central to the evaluation. Moreover, there is limited empirical information about how new knowledge is transformed into action. We respond to these knowledge gaps by analyzing (A) farmers’ perspectives on the collaborative learning process and (B) how farmers’ new knowledge can serve as the basis for changed actions. Theoretically, we are guided by second-order cybernetics and have integrated the Control Loop Model with Learning Loops to extend Kirkpatrick (Evaluating training programs: the four levels, 2nd edn. Berrett-Koehler Publisher, San Francisco, 1998) four-level evaluation scheme. We apply this to evaluate a 2-year collaborative learning process with two smallholder dairy farmer groups in Nakuru County, Kenya that aimed to co-develop local sustainable pathways to reduce milk losses. Results showed that farmers learned by (1) implementing corrective actions based on known cause–effect relations (single-loop learning); (2) discovering new cause–effect relations and testing their effect (double-loop learning); and (3) further questioning and changing their aims (triple-loop learning). Highlighting the importance of knowledge integration and co-production, this collaboration between farmers, researchers, and field assistants improved the farmers’ ability to respond, adapt, and intentionally transform their farming system in relation with complex sustainability challenges. Results demonstrate that the potential of our evaluation scheme to better reflect learning and empowerment experienced by actors involved in transdisciplinary research for sustainability.  相似文献   

4.
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   

5.
As climate is an important driver of vegetation distribution, climate change represents an important challenge to forestry. We (1) identify prevailing bioclimatic conditions for 49 relevant forest species in Portugal and (2) assess future shifts under climate change scenarios. We compute two bioclimatic indices (aridity and thermicity) and a new composite index, at ~1 km spatial resolution, and overlap with the species’ current ranges. Locations are based on a digital inventory, while climate parameters for both recent-past (1950–2000) and future climates (2041–2060), under RCP4.5 and RCP8.5, are provided by a multi-model ensemble of climate simulations. Results for future scenarios highlight an overall warming and drying trend. Supramediterranean and mesomediterranean climates will be significantly reduced, while thermomediterranean climates will dramatically increase, from their almost absence in current conditions to an area coverage of ~54 % in 2041–2060 for RCP8.5. There is also a clear shift from hyper-humid and humid to sub-humid and from the latter to semi-arid climates (area coverage of ~13 % in 2041–2060 for RCP8.5). Lower thermomediterranean sub-humid to semi-arid zones will cover the southern half of Portugal. These projections identify the most vulnerable (e.g. Betula pubescens, Quercus pyrenaica and Castanea sativa) and the most adapted (e.g. Quercus suber, Q. rotundifolia, Ceratonia siliqua, Pinus pinea, Quercus coccifera) species in future climates. Current bioclimatic zones associated with Eucalyptus globulus and Pinus pinaster, economically relevant species, will be moderately reduced and relocated. Possible adaptation measures are discussed to improve forest resilience to climate change, while maintaining its economic and environmental benefits.  相似文献   

6.
Using the focusing event framework, a comprehensive analysis of private households’ and businesses’ preparedness was undertaken in the aftermath of the 2002 and 2006 flood events on the Elbe River in Germany. In August 2002, preparedness of households (n = 235) and businesses (n = 103) was low: 30% of the households and 54% of the businesses took no precautionary measures before the flood event. Many undertaken emergency measures were ineffective, since only 26% of all households knew how to react when the flood warning came, and only 9% of businesses had an emergency plan in place. Due to this extreme flood, double-loop learning occurred in many households and businesses, so that many did implement precautionary measures. The distribution of adopted precautionary measures for households fits well to Preisendörfer’s low-cost hypothesis, but does not apply for businesses. Only 10% of the households (n = 112), but still 29% of the businesses (n = 41) were unprepared before the flood in 2006. Significant improvement in flood preparedness activities is still necessary. Particularly for businesses, regulatory programs and programs encouraging proactive behaviour should be implemented. The focusing event framework proofed to be a useful tool for a differentiated analysis of the responses to and learning due to a disaster also in the commercial and private sector.  相似文献   

7.
The forest–grassland mosaics of southern Brazil have been subject to many land use and policy changes over the decades. Like many grasslands around the world, the Campos grasslands are declining with few conservation efforts underway. In contrast, forests receive much attention and many incentives. It is hypothesized that perception of land cover has the potential to shape ecosystems. Here we conduct a questionnaire to further our understanding of decision-making practices that alter landscapes (Campos grassland, Araucaria forest, agriculture and plantation) and direct land policies in the region. Our analysis reveals that plantations are significantly less desirable than the other landscape types. However, plantation land use has increased by 87 % over the past few decades, as a result of industry and government incentives. The proportions of other landscape types have remained consistent over the past two decades. Restoration of native vegetation is not a priority of landowners and restoration would require a financial incentive.  相似文献   

8.
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   

9.
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   

10.
Crop diversity is central to traditional risk management practices on the Andean Altiplano and may find renewed importance in adapting to climate change. This study explored the role of crop diversity in farmers’ adaptation actions in eight Aymara communities on the northern Bolivian Altiplano. Using a combination of quantitative and qualitative methods, including multifactor analysis and a community resilience self-assessment, we investigated how farmers’ use of diversity in adaptation is related to their perceptions of crop and variety tolerances and other environmental, social, and economic factors. Few crops and varieties were perceived as tolerant to increasingly intense and unpredictable drought, frost, hail, and pest and disease outbreaks. Some local crops and varieties were perceived as vulnerable to emerging conditions (e.g. oca, papalisa, isaño), whereas bitter potatoes and wild relatives of quinoa and cañahua were perceived as highly stress tolerant and provide food in harsh periods. A total 19% of households surveyed (N = 193) had introduced new crops or varieties—often disease resistant or early maturing—as an adaptive action. Introduction of commercial crops was a common adaptation action, reflecting farmers’ response to warming temperatures and changing economic opportunities, but greater sensitivity of the introduced crops may cause maladaptation. Despite intensification of cropping systems, households continue to maintain a median four potato varieties with different tolerance traits, yet this risk management practice was not perceived as adaptation. Strengthening resilience will require a combination of actions, including maintaining and expanding crop portfolios and restoring soil and ecosystem health, using both traditional and innovative approaches.  相似文献   

11.
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   

12.
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   

13.
International Disaster Risk Reduction Frameworks and Indian Plans advocate shared responsibility for reducing disaster risk, in which community vulnerability and resilience conditions are central. This paper presents a case study from the Indian Himalaya (Kullu District) of community vulnerability and resilience conditions following damaging floods, primarily the 1994 Phojal Nalla flood, through the concepts of community heritage and capital. Data were collected in the period 2013–2016, using semi-structured interviews (n?=?129), village reconnaissance and archival/contemporary data searches. The connections between heritage, capital, vulnerability and resilience are complex, but results demonstrate ‘knowledge’ is the principal driver of resilience conditions, via facets of heritage (e.g. religious infrastructure and activities, traditional architectural vernacular, and multi-generational attachments to place) and capital (e.g. income diversification, access to communication technologies, societal welfare measures and positive interactions with water). Persisting vulnerabilities stem from differential access to and implementation of best practice knowledge, governed by social, economic and political conditions. Further improvements in risk reduction require greater consideration of the following: (1) the integration of community local knowledge into the overall disaster management process; (2) the opportunities offered by mobile phone and other technologies for generating and sharing knowledge across society; and (3) the value of under-utilised knowledge of past disaster events, assembled from a systematic evaluation of oral, documentary and landscape evidence, to risk reduction.  相似文献   

14.
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   

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.
Eomecon chionantha Hance, the only species in the genus Eomecon, is an angiosperm species endemic to China. Here we investigated the pollination syndrome, pollinator generalization of E. chionantha. Our results showed that the individual flower longevity of E. chionantha was 3–5 days. The flowering phenology of E. chionantha can be divided into five phases. We found significant differences in the pollination efficiency of the different insects visiting E. chionantha with bees and flies being the most efficient pollinators. This, in addition to floral morphology and phenology, suggests that E. chionantha is generalized on bees and flies and possesses an outcrossing, partially self-compatible and pollinator-dependent breeding system.  相似文献   

17.
Experimental studies of interactions between two amphipod species (Gmelinoides fasciatus and Gammarus lacustris) showed that predation is the basic mechanism accounting for their mutual exclusion in nature. Mortality from predation among similar-sized specimens of both species at an equal abundance ratio was similar (24–25% in G. lacustris and 27–30% in G. fasciatus). The displacement of G. lacustris by G. fasciatus was observed when the latter was dominant. Adult G. fasciatus and G. lacustris successfully preyed on juveniles of their competitors and did not differ significantly in daily food consumption as a percentage of body weight: 6–24% at a fresh body weight of 18–24 mg in both species. The potential for rapid population growth under new conditions contributed to the success of the invasive Baikal species G. fasciatus in displacing G. lacustris from many water bodies of Russia.  相似文献   

18.
Dugout canoes are traditional boat types made from a single tree trunk. This type of boat can reveal unique connections between forest and fisheries in coastal areas: their construction and the species used depend on the local ecological knowledge of artisans and the plant resources available and are also influenced by the type of fisheries in which the canoe will be used. Our objective was to analyze how dugout canoes are constructed, maintained, and currently used in the central coastal region of Santa Catarina, Brazil. The study emphasizes the interaction between the use of forest resources and artisanal fishing in this coastal environment. The data collected were based on interviews with 30 artisans and participant observation. Schizolobium parahyba (Vell.) Blake, Ocotea porosa (Nees & Mart.) Barroso, Ocotea Aubl../Nectandra Roll. Ex Rottb., and Aspidosperma Mart. & Zucc. are the main taxa used to construct the canoes. Many canoe sizes are used, and based on the boat type, the trunk diameters needed to construct them varies from 0.6 to 2.9 m and trunk heights from 4 to 10 m. Different types of canoe are used according to the type of fishing and especially to the environment conditions. The construction of canoes in the region has decreased due to difficulties in acquiring wood, changes in fishing activities, and reasons related to labor and apprenticeship, all causes related to modernization of the society and urban growth. The knowledge of plant species used can contribute to shape policies to improve forest management. The survival of cultural practices in artisanal fishing communities should be stimulated in sustainable development programs, and it involves maintaining ecological and technical knowledge related to fishing and the plant resources used to manufacture and maintain fishing equipment.  相似文献   

19.
Despite there being considerable research and knowledge surrounding the risks of climate change on agricultural productivity, fewer studies have examined risks from a whole-of-chain perspective (i.e. from producer to consumer) and the perceptions of consumers about the climate adaptation strategies of food businesses. This paper presents the findings of a survey of 1532 Australian consumers and how they might respond to a food company’s climate adaptation strategy. Three respondent archetypes, ‘Eco-warriors’ (n = 557), ‘Undecideds’ (n = 600) and ‘Abdicators’ (n = 375), were identified based on their perceptions of risks associated with climate change and their attitudes towards climate adaptation. Further analysis was carried out to understand how each group of respondents would respond to adaptation strategies employed by food companies. Based on the findings of this study, two main challenges are presented for food value chains: (1) translating consumer needs and preferences to niche opportunities arising from adaptation and (2) understanding how best to communicate adaptation benefits based on varying attitudes and information needs. By addressing these challenges, synergies between adaptation goals and competitive strategies in food value chains may be achieved.  相似文献   

20.
The remnants of chironomid larvae from layers of the 10-cm-thick bottom sediment in Lake Oron have been studied. Six taxons unknown in the current chironomid fauna of the lake have been identified: Abiskomyia rivalis, Corynoneura arctica-type, Mesocricotopus thienemanni, Metriocnemus eurynotus-type, Nanocladius rectinervis-type, and Robackia pilicauda. The most probable reasons for the disappearance of these species from the Oron fauna, which are related to environmental changes caused by global climate changes, are considered.  相似文献   

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