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1.
Three methods of gathering local and traditional knowledge of Indigenous Peoples were used to assess environmental changes and human impacts in Russian boreal forest communities: structured interviews, followed by an unstructured interview, and an education/training workshop. The most important environment changes reported by Indigenous Peoples included the disappearance of animals and plants, climate changes, a decrease in forest and shrub area, and human impacts such as poaching, forests fires, industrial logging, clearing of forests for firewood, and water pollution by industrial wastes and discharges. We propose establishment of the Boreal Residents' Network for Socio-environment Assessments and Education for Sustainable Development to acquire local and traditional knowledge as a supplement to scientific monitoring. The proposed approach would involve permanent inhabitants living in a broad range of boreal forests to gather local and traditional knowledge and assessments. This could lead to a meta-database to share with international networks.  相似文献   

2.
We synthesize recent results from lake-sediment studies of Holocene fire-climate-vegetation interactions in Alaskan boreal ecosystems. At the millennial time scale, the most robust feature of these records is an increase in fire occurrence with the establishment of boreal forests dominated by Picea mariana: estimated mean fire-return intervals decreased from ≥300 yrs to as low as ∼80 yrs. This fire-vegetation relationship occurred at all sites in interior Alaska with charcoal-based fire reconstructions, regardless of the specific time of P. mariana arrival during the Holocene. The establishment of P. mariana forests was associated with a regional climatic trend toward cooler/wetter conditions. Because such climatic change should not directly enhance fire occurrence, the increase in fire frequency most likely reflects the influence of highly flammable P. mariana forests, which are more conducive to fire ignition and spread than the preceding vegetation types (tundra, and woodlands/forests dominated by Populus or Picea glauca). Increased lightning associated with altered atmospheric circulation may have also played a role in certain areas where fire frequency increased around 4000 calibrated years before present (BP) without an apparent increase in the abundance of P. mariana. When viewed together, the paleo-fire records reveal that fire histories differed among sites in the same modern fire regime and that the fire regime and plant community similar to those of today became established at different times. Thus the spatial array of regional fire regimes was non-static through the Holocene. However, the patterns and causes of the spatial variation remain largely unknown. Advancing our understanding of climate-fire-vegetation interactions in the Alaskan boreal biome will require a network of charcoal records across various ecoregions, quantitative paleoclimate reconstructions, and improved knowledge of how sedimentary charcoal records fire events. In this paper, charcoal refers to macroscopic (≥180 μm) as opposed to microscopic (< 180 μm) particles unless indicated otherwise. Radiocarbon ages were converted to calibrated years before AD 1950 using the atmospheric calibration data set (Stuiver et al. 1998).  相似文献   

3.
全球气候变化对森林生态系统的影响   总被引:52,自引:1,他引:52  
人类活动所引起的温室效应及由此造成的全球气候变化和对全球生态环境的影响正越来越引起人们的关注。作为全球陆地生态系统一个重要组分的森林对未来气候变化的响应更是人们关注的重点。文中系统地论述了未来气候变化对森林生态系统树种组成、林分结构、分布和生产力的潜在响应,提出了今后需要加强的一些研究领域。  相似文献   

4.
Mitigation needs adaptation: Tropical forestry and climate change   总被引:1,自引:0,他引:1  
The relationship between tropical forests and global climate change has so far focused on mitigation, while much less emphasis has been placed on how management activities may help forest ecosystems adapt to this change. This paper discusses how tropical forestry practices can contribute to maintaining or enhancing the adaptive capacity of natural and planted forests to global climate change and considers challenges and opportunities for the integration of tropical forest management in broader climate change adaptation. In addition to the use of reduced impact logging to maintain ecosystem integrity, other approaches may be needed, such as fire prevention and management, as well as specific silvicultural options aimed at facilitating genetic adaptation. In the case of planted forests, the normally higher intensity of management (with respect to natural forest) offers additional opportunities for implementing adaptation measures, at both industrial and smallholder levels. Although the integration in forest management of measures aimed at enhancing adaptation to climate change may not involve substantial additional effort with respect to current practice, little action appears to have been taken to date. Tropical foresters and forest-dependent communities appear not to appreciate the risks posed by climate change and, for those who are aware of them, practical guidance on how to respond is largely non-existent. The extent to which forestry research and national policies will promote and adopt management practices in order to assist production forests adapt to climate change is currently uncertain. Mainstreaming adaptation into national development and planning programs may represent an initial step towards the incorporation of climate change considerations into tropical forestry.  相似文献   

5.
Afforestation has the potential to offset the increased emission of atmospheric carbon dioxide and has therefore been proposed as a strategy to mitigate climate change. Here we review the opportunities for carbon (C) offsets through open lichen woodland afforestation in the boreal forest of eastern Canada as a case study, while considering the reversal risks (low productivity, fires, insect outbreaks, changes in land use and the effects of future climate on growth potential as well as on the disturbances regime). Our results suggest that : (1) relatively low growth rate may act as a limiting factor in afforestation projects in which the time available to increase C is driven by natural disturbances; (2) with ongoing climate change, a global increase in natural disturbance rates, mainly fire and spruce budworm outbreaks, may offset any increases in net primary production at the landscape level; (3) the reduction of the albedo versus increase in biomass may negatively affect the net climate forcing; (4) the impermanence of C stock linked to the reversal risks makes this scenario not necessarily cost attractive. More research, notably on the link between fire risk and site productivity, is needed before afforestation can be incorporated into forest management planning to assist climate change mitigation efforts. Therefore, we suggest that conceivable mitigation strategies in the boreal forest will likely have to be directed activities that can reduce emissions and can increase C sinks while minimizing the reversal impacts. Implementation of policies to reduce Greenhouse Gases (GHG) in the boreal forest should consider the biophysical interactions, the different spatial and temporal scales of their benefits, the costs (investment and benefits) and how all these factors are influenced by the site history.  相似文献   

6.
This paper addresses the combined effects of two sources of disturbance on the boreal forest – climate change and the economic relations of industrial forestry. It describes a theoretical blueprint constructed of concepts from the theory of dissipative structures (derived from the discipline of physical chemistry) and world-systems theory (derived from the discipline of sociology) into a proposed integrated theory pivoting on the concept of social vulnerability. The goal is to examine the key concepts of this theory – vulnerability, resilience and adaptive capacity – as elements of the complex systems perspective provided by dissipative structure principles. The focus on social vulnerability provides the means to establish the role of external economic linkages relevant to industrial forestry – the core/periphery relations of the world-system – as they influence the social vulnerability of the boreal forest SESs. These systems are posited as embedded peripheries, following world-system criteria, and as the focal scale of analysis within a larger hierarchically organized dissipative structure. The goal is to suggest and stimulate ideas for further discussion and exploration, motivated by the premise that any successful climate change mitigation efforts depend on having sound theoretical foundations on which to stand.  相似文献   

7.
Preventing dangerous climate change requires actions on several sectors. Mitigation strategies have focused primarily on energy, because fossil fuels are the main source of global anthropogenic greenhouse gas emissions. Another important sector recently gaining more attention is the forest sector. Deforestation is responsible for approximately one fifth of the global emissions, while growing forests sequester and store significant amounts of carbon. Because energy and forest sectors and climate change are highly interlinked, their interactions need to be analysed in an integrated framework in order to better understand the consequences of different actions and policies, and find the most effective means to reduce emissions. This paper presents a model, which integrates energy use, forests and greenhouse gas emissions and describes the most important linkages between them. The model is applied for the case of Finland, where integrated analyses are of particular importance due to the abundant forest resources, major forest carbon sink and strong linkage with the energy sector. However, the results and their implications are discussed in a broader perspective. The results demonstrate how full integration of all net emissions into climate policy could increase the economic efficiency of climate change mitigation. Our numerical scenarios showed that enhancing forest carbon sinks would be a more cost-efficient mitigation strategy than using forests for bioenergy production, which would imply a lower sink. However, as forest carbon stock projections involve large uncertainties, their full integration to emission targets can introduce new and notable risks for mitigation strategies.  相似文献   

8.
Anthropogenic climate change is progressively transforming the environment despite political and technological attempts to reduce greenhouse gas emissions to tackle global warming. Here we propose that greater insight and understanding of the health-related impacts of climate change can be gained by integrating the positivist approaches used in public health and epidemiology, with holistic social science perspectives on health in which the concept of ‘wellbeing’ is more explicitly recognised. Such an approach enables us to acknowledge and explore a wide range of more subtle, yet important health-related outcomes of climate change. At the same time, incorporating notions of wellbeing enables recognition of both the health co-benefits and dis-benefits of climate change adaptation and mitigation strategies across different population groups and geographical contexts. The paper recommends that future adaptation and mitigation policies seek to ensure that benefits are available for all since current evidence suggests that they are spatially and socially differentiated, and their accessibility is dependent on a range of contextually specific socio-cultural factors.  相似文献   

9.
Forest Fires and Climate Change in the 21ST Century   总被引:3,自引:0,他引:3  
Fire is the major stand-renewing disturbance in the circumboreal forest. Weather and climate are the most important factors influencing fire activity and these factors are changing due to human-caused climate change. This paper discusses and synthesises the current state of fire and climate change research and the potential direction for future studies on fire and climate change. In the future, under a warmer climate, we expect more severe fire weather, more area burned, more ignitions and a longer fire season. Although there will be large spatial and temporal variation in the fire activity response to climate change. This field of research allows us to better understand the interactions and feedbacks between fire, climate, vegetation and humans and to identify vulnerable regions. Lastly, projections of fire activity for this century can be used to explore options for mitigation and adaptation.  相似文献   

10.
The roles of forest management and the use of timber for energy in the global carbon cycle are discussed. Recent studies assert that past forest management has been accelerating climate change, for example in Europe. In addition, the increasing tendency to burn timber is an international concern. Here, we show a new way of carbon accounting considering the use of timber as a carbon neutral transfer into a pool of products. This approach underlines the robust, positive carbon mitigation effects of sustainable timber harvesting. Applying this new perspective, sustainable timber use can be interpreted not as a removal but a prevention of carbon being converted within the cycle of growth and respiration. Identifying timber use as a prevention rather than a removal leads to the understanding of timber use as being no source of carbon emissions of forests but as a carbon neutral transfer to the product pool. Subsequently, used timber will then contribute to carbon emissions from the pool of forest products in the future. Therefore, timber use contributes to carbon mitigation by providing a substantial delay of emissions. In a second step, the carbon model is applied to results of a previous study in which different timber price scenarios were used to predict timber harvests in Bavarian forests (Germany). Thus, the influence of the economic dimension “timber price” on the ecological dimension carbon sequestration was derived. It also shows that these effects are stable, even if an increasing tendency of burning timber products for producing energy is simulated. Linking an economic optimization to a biophysical model for carbon mitigation shows how the impact of management decisions on the environment can be derived. Overall, a sustainably managed system of forests and forest products contributes to carbon mitigation in a positive, stable way, even if the prices for (energy) wood rise substantially.  相似文献   

11.
Pakistan has very low forest cover, but these forests are very diverse in nature and of significant importance for the livelihood security of millions of rural people who live in and around these forests. Policies, institutions and processes form the context within which individuals and households construct and adapt livelihood strategies, on the other hand these institutionally shaped livelihood strategies may have an impact on the sustainability of natural resource use. The present paper aims to critically analyse the forest policies of Pakistan. Implications for sustainable forest management and livelihood security of forest dependent people are also given. The first forest policy of Pakistan was announced in 1955 followed by the forest policies of 1962, 1975, 1980, 1988 as part of the National Agricultural Policy, 1991, and the latest in 2001. Most of the forest policies were associated with the change of government. There was much rhetoric in some recent policies regarding the concept of “participation” and “sustainable livelihoods” but in practice these policies are also replica of the previously top-down, autocratic and non-participatory forest policies. Pakistan needs to develop a sustainable, workable, research-based, and people-friendly forest policy enable to catering to the changing needs of stakeholders including government.  相似文献   

12.
森林植被变化对流域水文影响的争论   总被引:38,自引:2,他引:38  
针对“森林能否增雨、森林能否减少年径流量、调节枯水径流以及能否削减洪峰”等问题,综述了各种观点,分析了出现分歧的原因。作者认为森林对降水量的影响不大,森林植被的存在一般减少年径流量,而对调节枯水径流以及削减洪峰等的作用则因地带、因流域尺度而异。研究方法的局限性、研究对象的复杂性以及区域差异和尺度的影响,是导致争论的主要原因。正确评价森林的水文效应,应该注意地带性差异、尺度的影响以及不同森林的类型等。  相似文献   

13.
Planting urban trees and expanding urban forest canopy cover are often considered key strategies for reducing climate change impacts in urban areas. However, urban trees and forests can also be vulnerable to climate change through shifts in tree habitat suitability, changes in pests and diseases, and changes in extreme weather events. We developed a three-step framework for urban forest vulnerability assessment and adaptation that scales from regional assessment to local on-the-ground action. We piloted this framework in the Chicago region in 10 locations representing an urban-exurban gradient across a range of socioeconomic capacities. The majority of trees across a seven-county region had low to moderate vulnerability, but many of the least vulnerable species were nonnative invasive species. Urban forests in the 10 pilot locations ranged in vulnerability largely due to differences in economic and organizational adaptive capacity. Adaptation actions selected in these locations tended to focus on increased biodiversity and restoration of natural disturbance regimes. However, adaptation actions in more developed sites also included incorporating new species or cultivars. Lessons learned from the pilot area can be used to inform future efforts in other urban areas.  相似文献   

14.

Climate change is a global phenomenon that affects biophysical systems and human well-being. The Paris Agreement of the United Nations Framework Convention on Climate Change entered into force in 2016 with the objective of strengthening the global response to climate change by keeping global temperature rise this century well below 2 °C above pre-industrial levels and to pursue efforts to limit the temperature increase even further to 1.5 °C. The agreement requires all Parties to submit their “nationally determined contributions” (NDCs) and to strengthen these efforts in the years ahead. Reducing carbon emissions from deforestation and forest degradation is an important strategy for mitigating climate change, particularly in developing countries with large forests. Extensive tropical forest loss and degradation have increased awareness at the international level of the need to undertake large-scale ecological restoration, highlighting the need to identify cases in which restoration strategies can contribute to mitigation and adaptation. Here we consider Brazil as a case study to evaluate the benefits and challenges of implementing large-scale restoration programs in developing countries. The Brazilian NDC included the target of restoring and reforesting 12 million hectares of forests for multiple uses by 2030. Restoration of native vegetation is one of the foundations of sustainable rural development in Brazil and should consider multiple purposes, from biodiversity and ecosystem services conservation to social and economic development. However, ecological restoration still presents substantial challenges for tropical and mega-diverse countries, including the need to develop plans that are technically and financially feasible, as well as public policies and monitoring instruments that can assess effectiveness. The planning, execution, and monitoring of restoration efforts strongly depend on the context and the diagnosis of the area with respect to reference ecosystems (e.g., forests, savannas, grasslands, wetlands). In addition, poor integration of climate change policies at the national and subnational levels and with other sectorial policies constrains the large-scale implementation of restoration programs. The case of Brazil shows that slowing deforestation is possible; however, this analysis highlights the need for increased national commitment and international support for actions that require large-scale transformations of the forest sector regarding ecosystem restoration efforts. Scaling up the ambitions and actions of the Paris Agreement implies the need for a global framework that recognizes landscape restoration as a cost-effective nature-based solution and that supports countries in addressing their remaining needs, challenges, and barriers.

  相似文献   

15.
Tropical forests in countries like thePhilippines are important sources and sinks of carbon(C). The paper analyzes the contribution of Philippineforests in climate change mitigation. Since the 1500s,deforestation of 20.9 M ha (106 ha) of Philippineforests contributed 3.7 Pg (1015 g) of C to theatmosphere of which 2.6 Pg were released this century. At present, forest land uses store 1091 Tg(1012 g) of C and sequester 30.5 Tg C/yr whilereleasing 11.4 Tg C/yr through deforestation andharvesting. In the year 2015, it is expected that thetotal C storage will decline by 8% (1005 Tg) andtotal rate of C sequestration will increase by 17%(35.5 Tg/yr). This trend is due to the decline innatural forest area accompanied by an increase intree plantation area. We have shown that uncertaintyin national C estimates still exists because they arereadily affected by the source of biomass and Cdensity data. Philippine forests can act as C sink by:conserving existing C sinks, expanding C stocks, andsubstituting wood products for fossil fuels. Here weanalyze the possible implications of the provisions ofthe Kyoto Protocol to Philippine forests. Finally, wepresent current research and development efforts ontropical forests and climate change in the Philippinesto improve assessments of their role in the nations Cbudgets.  相似文献   

16.
The broad objective of this special issue of Mitigation and Adaptation Strategies for Global Change is to address some of the gaps in our knowledge and understanding of the policies, programs, and measures that might be applied to natural hazards and their impacts in an era of climate change. Given the global impacts of climate change and world-wide pattern of increasing losses from natural hazards we necessarily adopt an international perspective. The specific goals of the special issue are to: (a) encompass experiential aspects, emphasizing current practice of mitigation and its associated measures, and their results; and (b) explore primary or root causes of alarming shifts in human and economic costs of environmental extremes. Special emphasis is placed on how human activities are playing a key role in enhancing vulnerability to NTEE (nature-triggered environmental extremes), quite independently from the anthropogenic causes of climate change. The goals are also (c) to examine costs, risks, and benefits (of all kinds including social, political, ecological) of mitigation, and adjustment and adaptation measures; and (d) analyze policy implications of alternative measures. These components are expected to make significant contributions to policy considerations – formulation, implementation and evaluation. There is much uncertainty about the rate of climate change; however, the fact of increase of the atmospheric temperature in the last century is no longer a subject of scientific or policy debate. Due to such changes in the geophysical parameters, certain types of nature-triggered environmental extreme events are likely to continue to increase. How global warming will affect regional climates and pertinent variables is not well known, limiting our ability to predict consequential effects. This factor poses serious constraints against any straightforward policy decisions. Research findings of the work of this volume reaffirm that human dimensions, specifically our awareness and decision-making behavior, are powerful explanatory factors of increasing disaster losses. Disaster mitigation through addressing human, social, and physical vulnerability is one of the best means for contributing to ‘climate change adaptation plans’, and sustainable development goals. Recent lessons from various countries have depicted that the formulation of mitigation strategies cannot be exclusively top-down as it requires social, political, and cultural acceptance and sense of ownership. An interactive, participatory process, involving local communities, produces best expected outcomes concerning mitigation, preparedness, and recovery. An emerging consensus is that there is a need to move towards the ‘mission’ of the International Strategy for Disaster Reduction which aims at building disaster resilient communities by promoting increased awareness of the importance of disaster reduction as an integral component of sustainable development, with the goal of reducing human, social, economic and environmental losses due to natural hazards and related technological and environmental disasters. Sharing of best practices and lessons globally is certain to produce more efficiency and understanding in policy and decision making.  相似文献   

17.
Nowadays, adaptation has become a key focus of the scientific and policy-making communities and is a major area of discussion in the multilateral climate change process. As climate change is projected to hit the poorest the hardest, it is especially important for developing countries to pay particular attention to the management of natural resources and agricultural activities. In most of these countries such as Cameroon, forest can play important role in achieving broader climate change adaptation goals. However, forest generally receives very little attention in national development programme and strategies such as policy dialogues on climate change and poverty reduction strategies. Using a qualitative approach to data collection through content analysis of relevant Cameroon policy documents, the integration of climate change adaptation was explored and the level of attention given to forests for adaptation analysed. Results indicate that, with the exception of the First National Communication to UNFCCC that focused mostly on mitigation and related issues, current policy documents in Cameroon are void of tangible reference to climate change, and hence failing in drawing the relevance of forest in sheltering populations from the many projected impacts of climate change. Policies related to forest rely on a generalized concept of sustainable forest management and do not identify the specific changes that need to be incorporated into management strategies and policies towards achieving adaptation. The strategies and recommendations made in those documents only serve to improve understanding of Cameroon natural resources and add resilience to the natural systems in coping with anthropogenic stresses. The paper draws attention to the need to address the constraints of lack of awareness and poor flow of information on the potentials of forests for climate change adaptation. It highlights the need for integrating forest for adaptation into national development programmes and strategies, and recommends a review of the existing environmental legislations and their implications on poverty reduction strategy and adaptation to climate change.  相似文献   

18.
As climate changes due to rising concentrations of greenhouse gases in the atmosphere, agriculture will be one of the key human activities affected. Projections show that while overall global food production in the coming decades may keep pace with the food requirements of a growing world population, climate change might worsen existing regional disparities because it will reduce crop yields mostly in lands located at lower latitudes where many developing countries are situated. Strategies to enhance local adaptation capacity are therefore needed to minimize climatic impacts and to maintain regional stability of food production. At the same time, agriculture as a sector offers several opportunities to mitigate the portion of global greenhouse gas emissions that are directly dependent upon land use, land-use change, and land-management techniques. This paper reviews issues of agriculture and climate change, with special attention to adaptation and mitigation. Specifically, as adaptation and mitigation strategies in agriculture are implemented to alleviate the potential negative effects of climate change, key synergies need to be identified, as mitigation practices may compete with modifications to local agricultural practices aimed at maintaining production and income. Under future climate and socio-economic pressures, land managers and farmers will be faced with challenges in regard to selecting those mitigation and adaptation strategies that together meet food, fiber and climate policy requirements.  相似文献   

19.
Old growth mangroves in existing protected areas store more carbon than restored forests or plantations. Carbon storage in such forests has economic value independent of additionality, offering opportunities for policy makers to ensure their maintenance, and inclusion in climate change mitigation strategies. Mangrove forests of the Everglades National Park (ENP), South Florida, though protected, face external stressors such as hydrological alterations because of flooding control structures and agriculture impacts and saltwater intrusion as a result of increasing sea level rise. Moreover, decreased funding of Everglades’ restoration activities following the recent economic crisis (beginning 2008) threatens the restoration of the Greater Everglades including mangrove dominated coastal regions. We evaluate several economic and ecological challenges confronting the economic valuation of total (vegetation plus soil) organic carbon (TOC) storage in the ENP mangroves. Estimated TOC storage for this forested wetland ranges from 70 to 537 Mg C/ha and is higher than values reported for tropical, boreal, and temperate forests. We calculate the average abatement cost of C specific for ENP mangroves to value the TOC from $2–$3.4 billion; estimated unit area values are $13,859/ha–$23,728/ha. The valuation of the stored/legacy carbon is based on the: 1) ecogeomorphic attributes, 2) regional socio-economic milieu, and 3) status of the ENP mangroves as a protected area. The assessment of C storage estimates and its economic value can change public perception about how this regulating ecosystem service of ENP mangrove wetlands (144,447 ha) supports human well-being and numerous economic activities. This perception, in turn, can contribute to future policy changes such that the ENP mangroves, the largest mangrove area in the continental USA, can be included as a potential alternative in climate change mitigation strategies.  相似文献   

20.
This paper aims to contribute new insights globally and regionally on how carbon forest mitigation contributes to sustainable development in South America. Carbon finance has emerged as a potential policy option to tackling global climate change, degradation of forests, and social development in poor countries. This paper focuses on evaluating the socioeconomic impacts of a set of forest based mitigation pilot projects that emerged under the United Nations Framework Convention on Climate Change. The paper reviews research conducted in 2001–2002, drawing from empirical data from four pilot projects, derived from qualitative stakeholder interviews, and complemented by policy documents and literature. Of the four projects studied three are located in frontier areas, where there are considerable pressures for conversion of standing forest to agriculture. In this sense, forest mitigation projects have a substantial role to play in the region. Findings suggest however, that all four projects have experienced cumbersome implementation processes specifically, due to weak social objectives, poor communication, as well as time constraints. In three out of four cases, stakeholders highlighted limited local acceptance at the implementation stages. In the light of these findings, we discuss opportunities for implementation of future forest based mitigation projects in the land use sector.  相似文献   

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