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1.
Illegal activities and use of park resources are the main challenges facing mountain gorilla (Gorilla beringei beringei) conservation and the protection of their habitats in the East Africa’s Greater Virunga Transboundary Landscape (GVTL). Indigenous residents around GVTL are considered the primary illegal users of park resources. Despite this, there is limited understanding of the current and past perceptions of indigenous residents living in communities adjacent to two GVTL parks; Volcanoes National Park in Rwanda and Mgahinga Gorilla National Park in Uganda. Equally, there is also limited understanding regarding the actual incidences of illegal activities inside both parks. This paper addresses these gaps. Perception data were collected from indigenous residents living adjacent to both parks. Further, Ranger-based Monitoring (RbM) data from both parks were analyzed to determine actual numbers and types of illegal activities over the 9-year period. Interestingly, findings indicated that residents perceived the prevalence of illegal activities to be decreasing across GVTL. To the contrary, RbM findings indicated that the number of actual illegal activities was increasing significantly, particularly in Volcanoes National Park. The discrepancy found between the two perspectives provides for a discussion of the social biases potentially present in these data, and their implications for management. Results also illuminated the subsistence-related nature of most illegal behaviors and suggest that to reduce illegal activities and local dependency on park resources, park management must work with communities and support them in tapping into alternative livelihoods and finding ways to address community household subsistence needs.  相似文献   

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Young, Charles A., Marisa I. Escobar‐Arias, Martha Fernandes, Brian Joyce, Michael Kiparsky, Jeffrey F. Mount, Vishal K. Mehta, David Purkey, Joshua H. Viers, and David Yates, 2009. Modeling the Hydrology of Climate Change in California’s Sierra Nevada for Subwatershed Scale Adaptation. Journal of the American Water Resources Association (JAWRA) 45(6):1409‐1423. Abstract: The rainfall‐runoff model presented in this study represents the hydrology of 15 major watersheds of the Sierra Nevada in California as the backbone of a planning tool for water resources analysis including climate change studies. Our model implementation documents potential changes in hydrologic metrics such as snowpack and the initiation of snowmelt at a finer resolution than previous studies, in accordance with the needs of watershed‐level planning decisions. Calibration was performed with a sequence of steps focusing sequentially on parameters of land cover, snow accumulation and melt, and water capacity and hydraulic conductivity of soil horizons. An assessment of the calibrated streamflows using goodness of fit statistics indicate that the model robustly represents major features of weekly average flows of the historical 1980‐2001 time series. Runs of the model for climate warming scenarios with fixed increases of 2°C, 4°C, and 6°C for the spatial domain were used to analyze changes in snow accumulation and runoff timing. The results indicated a reduction in snowmelt volume that was largest in the 1,750‐2,750 m elevation range. In addition, the runoff center of mass shifted to earlier dates and this shift was non‐uniformly distributed throughout the Sierra Nevada. Because the hydrologic model presented here is nested within a water resources planning system, future research can focus on the management and adaptation of the water resources system in the context of climate change.  相似文献   

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《Local Environment》2007,12(5):457-469
This paper directs attention to conditions for climate adaptation as an important part of governing climate change in the local arena. Empirical focus is put on attempts to manage flood risks by means of risk management and planning in two Swedish municipalities. Following the need to widen our understanding of how, when and under what conditions climate adaptation occurs, three challenges are particularly emphasized from the case studies: facing the safety vs. scenery conflict where political priorities and reducing societal vulnerabilities prove difficult; the process of deciding what to adapt to, in which the troublesome role of knowledge is striking; and finally, taking responsibility for measures of flood protection. At the end of the paper, analytical generalizations illustrate the need to give increased attention to institutional challenges and challenges emanating from the science-policy interface in order to come to terms with the implementation deficit in governing climate change in the local arena.  相似文献   

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Climate change affects public land ecosystems and services throughout the American West and these effects are projected to intensify. Even if greenhouse gas emissions are reduced, adaptation strategies for public lands are needed to reduce anthropogenic stressors of terrestrial and aquatic ecosystems and to help native species and ecosystems survive in an altered environment. Historical and contemporary livestock production—the most widespread and long-running commercial use of public lands—can alter vegetation, soils, hydrology, and wildlife species composition and abundances in ways that exacerbate the effects of climate change on these resources. Excess abundance of native ungulates (e.g., deer or elk) and feral horses and burros add to these impacts. Although many of these consequences have been studied for decades, the ongoing and impending effects of ungulates in a changing climate require new management strategies for limiting their threats to the long-term supply of ecosystem services on public lands. Removing or reducing livestock across large areas of public land would alleviate a widely recognized and long-term stressor and make these lands less susceptible to the effects of climate change. Where livestock use continues, or where significant densities of wild or feral ungulates occur, management should carefully document the ecological, social, and economic consequences (both costs and benefits) to better ensure management that minimizes ungulate impacts to plant and animal communities, soils, and water resources. Reestablishing apex predators in large, contiguous areas of public land may help mitigate any adverse ecological effects of wild ungulates.  相似文献   

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For further development of organic agriculture, it will become increasingly essential to integrate experienced innovative practitioners in research projects. The characteristics of this process of co-learning have been transformed into a research approach, theoretically conceptualized as “experiential science” (Baars 2007, Baars and Baars 2007). The approach integrates social sciences, natural sciences, and human sciences. It is derived from action research and belongs to the wider field of transdiscliplinary research. In a dialogue-based culture of equality and mutual exchange the principal of a “bottom-up” experiential learning process can be stimulated and fully reflective. It provides an opportunity to develop organic agriculture as multiple best-practices based on transdisciplinary projects, cases studies, and case series. The aim of the article is to describe the methodological characteristics and the theoretical and practical potential of experiential science for research in and development of organic farming. Three characteristic projects are outlined to illustrate the main elements of the methodology: the retrospective reflection on intuitive and experiential knowledge held by farmers; the knowledge derived from on-farm experimentation; the exchange of knowledge and experiences between farming pioneers within a “masterclass” setting. The study concludes that experiential science offers an important philosophical reconciliation process whereby a synthesis of different approaches to research becomes possible in solving real-life problems: quantitative and qualitative, subjective and objective, reductionistic and holistic, practice and science. Recognizing that there are multiple elements contributing to the process of acquiring knowledge, experiential science draws on a broad field of scientific methods thereby integrating the hermeneutic approach of social sciences and the Humanities with the established methods of contemporary natural science.  相似文献   

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用果洛藏族自治州玛多1953~2004年气象资料及塘乃亥的黄河径流量资料,分析了玛多平均气温、降水量、累计积雪量、蒸发等与塘乃亥流量变化的关系,从气候角度探讨影响黄河断流的原因。  相似文献   

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/ Various types of recreational traffic impact hiking trails uniquely and cause different levels of trail degradation; however, trail head restrictions are applied similarly across all types of packstock. The purpose of this study was to assess the relative physical impact of hikers, llamas, and horses on recreational trails. Horse, llama, and hiker traffic were applied to 56 separate plots on an existing trail at Lubrecht Experimental Forest in western Montana. The traffic was applied to plots at intensities of 250 and 1000 passes along with a no-traffic control under both prewetted and dry trail conditions. Soil erosion potential was assessed by sediment yield and runoff (using a Meeuwig type rainfall simulator), changes in soil bulk density, and changes in soil surface roughness. Soil moisture, slope, and rainfall intensity were recorded as independent variables in order to evaluate the extent that they were held constant by the experimental design. Horse traffic consistently made more sediment available for erosion from trails than llama, hiker, or no traffic when analyzed across wet and dry trail plots and high and low intensity traffic plots. Although total runoff was not significantly affected by trail user, wet trail traffic caused significantly greater runoff than dry trail traffic. Llama traffic caused a significant increase in sediment yield compared to the control, but caused erosion yields not significantly different than hiker traffic. Trail traffic did not increase soil compaction on wet trails. Traffic applied to dry trail plots generally resulted in a significant decrease in soil bulk density compared to the control. Decreased soil bulk density was negatively correlated with increased sediment yield and appeared to result in increased trail roughness for horse traffic compared to hiker or llama traffic. Differences described here between llama and horse traffic indicate that trail managers may want to consider managing packstock llamas independent of horses.KEY WORDS: Recreational impacts; Sediment yield; Trail degradation  相似文献   

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The environmental impacts created by recreational visitors to the wet-dry tropics of Western Australia raise questions about the type of visitor and the capacity of remote areas to 'carry increasing numbers of visitors. This paper looks at those questions in regard to some of the more remote natural attractions in the tropical North Kimberley region. Three locations—Cape Domett at the mouth of the Ord River, the Admiralty Gulf and the Mitchell Plateau—illustrate the differences between attractions, visitors, patterns of visitor behavior and their impacts on the local environment. As the highly variable nature of the Australian wet-tropics renders the use of conventional site indicators of carrying capacity difficult, an ecological alternative is proposed for research. The dominance of local and other Australian four-wheel drivers to the Kimberley and the impacts they create are shown to challenge the government's promotion of the region to overseas visitors and its notion of tourism as a sustainable industry.  相似文献   

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This study provides an overview of the impacts of a proposed hydroelectric power project in the Western Himalayan region in India, using a primary database on floristic diversity and vegetation analysis. The remote sensing data revealed that in the submergence zone only mixed deciduous forest that occupies 807.5 ha area and has a wood biomass volume of 4,027,503 m3 is likely to be lost due to impoundment. A total of 165 plant species found in the submergence zone also occur in the influence and free draining catchment area of the project. In the influence zone of the project area only one tree species (Acer oblongum) is found under conservation threat category, which is also present in the free draining catchment of the project. The project affected population (6716 people) residing in the submergence and influence zone depend upon the surrounding forests for fuel wood, fodder, wild edibles etc., and most likely they will settle in the nearby areas, thus mounting more pressure on residual forests of the influence zone for various forest products. Further, from the vegetation analysis it is evident that several tree species (e.g. Lannea coromandelica, Terminalia alata, T. bellerica etc.), may face more pressure from exploitation as they provide a number of useful products and are represented in lower numbers in the forests of the project area. To compensate for the loss of various goods and services provided by the forests falling in the submergence zone and to offset the increased pressure of the project affected families on the forests of influence zone, a biodiversity management plan is suggested incorporating socio-economic considerations.  相似文献   

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dentification of groups that are similar in their floristic composition and structure (habitat types) is essential for conservation and forest managers to allocate high priority areas and to designate areas for reserves, refuges, and other protected areas. In this study, the use of indigenous knowledge for the identification of habitat types in the field was compared against an ecological characterization of habitat types, including their species composition obtained by using classification and ordination techniques for a tropical landscape mosaic in a rural Mayan area of Quintana Roo, Mexico. Plant diversity data calculated from 141 sampled sites chosen randomly on a vegetation class’s thematic map obtained by multispectral satellite image classification were used for this propose. Results indicated high similarity in the categorization of vegetation types between the Mayan classification and those obtained by cluster and detrended correspondence analysis. This suggests that indigenous knowledge has a practical use and can be comparable to that obtained by using science-based methods. Finally, identification and mapping of vegetation classes (habitat types) using satellite image classification allowed us to discriminate significantly different species compositions, in such a way that they can provide a useful mechanism for interpolating diversity values over the entire landscape.  相似文献   

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Knowledge of the effects of climate factors on net primary production (NPP) is pivotal to understanding ecosystem processes in the terrestrial carbon cycle. Our goal was to evaluate four different categories of effects (physical, climatic, NDVI, and all effects[global]) as predictors of forest NPP in eastern China. We developed regression models with data from 221 NPP in eastern China and identified the best model with each of the four categories of effects. Models explained a large part of the variability in NPP, ranging from 46.8% in global model to 36.5% in NDVI model. In the most supported global model, winter temperature and sunshine duration negatively affected NPP, while winter precipitation positively affected NPP. Thus, winter climate conditions play an important role in modulating forest NPP of eastern China. Spring temperature had a positive affect on NPP, which was likely because a favorable warm climate in the early growing season promotes forest growth. Forest NPP was also negatively affected by summer and autumn temperatures, possibly because these are related to temperature induced drought stress. In the NDVI model, forest NPP was affected by NDVI in spring (positive), summer (negative) and winter (negative) seasons. Our study provides insight into seasonal effects of climate and NPP of forest in China, as well as useful knowledge for the development of climate-vegetation models.  相似文献   

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Abstract: One of the largest karst springs in North China, the Jinci Springs, dried up and has remained dry since 1994. We develop a correlation analysis with time‐lag and a regression analysis with time‐lag to study the relation between spring flow and precipitation. This allows us to obtain a better understanding of karst hydrological processes by differentiating the contribution of variation in precipitation from anthropogenic impacts on the dry‐up of Jinci Springs. We divided the karstic hydrological processes into two phases: pre‐1961 and post‐1961. In the first phase (i.e., 1954‐1960) the groundwater recharge was affected by precipitation alone, and in the second phase (i.e., 1961‐1994) the groundwater recharge was influenced by both precipitation and human activities. Using precipitation and groundwater recharge data in the first phase, we set up a groundwater recharge model with time‐lags. By running the time‐lags model, we acquired the groundwater recharge likely to occur under the sole effect of precipitation in the second phase. Using a water‐balance calculation, we conclude that the groundwater recharge exhibited statistical stationarity, and the Jinci Springs dry‐up was the result of anthropogenic activities. At least three specific types of anthropogenic activities contributed to the drying‐up of Jinci Springs: (1) groundwater pumping accounts for 51%, (2) the dewatering from coal mining accounts for 33%, (3) and dam‐building 14%. The drying‐up of Jinci Springs meant that the groundwater drained from the aquifer’s fractures, and subsequently changed the structure of the karst aquifer. Although groundwater exploitation has been reduced, the flow at Jinci Springs has not reoccurred.  相似文献   

15.
This article examines key socio-ecological interactions identified during a climate change vulnerability assessment in the Alinytjara Wilurara natural resources management (NRM) region of South Australia. The complex local socio-ecological interactions are highlighted to guide a response to the challenge of adapting to climate change within the region. Recognising several key desert drivers which perpetuate degraded socio-ecological systems, this article recommends that a range of strategies be employed simultaneously to enhance local environmental management in association with remote indigenous communities, including: linking people and NRM more closely; tracking funding but ensuring systems can withstand periods of limited financial support; developing cross-sectoral and cross-institutional links; empowering and engaging communities; communicating effectively; and actively supporting local and traditional environmental knowledge. Unless climate change adaptation responses within the region are conceptualised and enacted within the context of complex local socio-ecological systems, NRM will not improve and social vulnerability will increase.  相似文献   

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Nigeria’s vegetation in general and some important tree species in particular are under increasing threats from several factors. Worsening climate and environmental conditions, enhanced by a huge population pressure on limited resources, are some of the dominant issues of discourse among scientists. This study investigated the density of Faidherbia albida, a nitrogen-fixing tree, that has been an important component of the farming systems of the smallholder farms in the degraded lands of Kano, Nigeria. Results indicate a 55% decrease in the density of the tree in the study area. The overall diversity of trees on the smallholder farms has also declined by 38%. The study concludes that while climate change may be a catalyst, woodfuel extraction and disease are the immediate factors for the decline of F. indica in the area. It recommends (1) the inclusion of this species in the list of endangered species for deliberate regeneration and protection by all stakeholders (2) an extended study that could lead to determining the specific role of climate change on the density of the tree in the study area.  相似文献   

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Abstract: Since the 1940s, snow water equivalent (SWE) has decreased throughout the Pacific Northwest, while water use has increased. Climate has been proposed as the primary cause of base‐flow decline in the Scott River, an important coho salmon rearing tributary in the Klamath Basin. We took a comparative‐basin approach to estimating the relative contributions of climatic and non‐climatic factors to this decline. We used permutation tests to compare discharge in 5 streams and 16 snow courses between “historic” (1942‐1976) and “modern” (1977‐2005) time periods, defined by cool and warm phases, respectively, of the Pacific Decadal Oscillation. April 1 SWE decreased significantly at most snow courses lower than 1,800 m in elevation and increased slightly at higher elevations. Correspondingly, base flow decreased significantly in the two streams with the lowest latitude‐adjusted elevation and increased slightly in two higher‐elevation streams. Base‐flow decline in the Scott River, the only study stream heavily utilized for irrigation, was larger than that in all other streams and larger than predicted by elevation. Based on comparison with a neighboring stream draining wilderness, we estimate that 39% of the observed 10 Mm3 decline in July 1‐October 22 discharge in the Scott River is explained by regional‐scale climatic factors. The remainder of the decline is attributable to local factors, which include an increase in irrigation withdrawal from 48 to 103 Mm3/year since the 1950s.  相似文献   

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An on-site visitor survey instrument was developed to examine visitor perceptions of resource impacts resulting from backcountry hiking activities. The survey was conducted in the Bear Lake Corridor of Rocky Mountain National Park, CO and examined visitor characteristics that may influence visitor perceptions of specific resource conditions. Findings indicate that visitors are more perceptive of recreation-related resource impacts that are the result of undesirable behavior and, while visitors do perceive resource impacts, visitors tend to be more affected by crowding. Factors such as local ecological knowledge and knowledge of minimal-impact practices positively influence visitor perceptions of resource impacts. These findings support the use of visitor education on ecological knowledge and minimum-impact as a means of increasing visitor awareness of recreation impact issues.  相似文献   

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