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891.
Anthropogenic biomass burning in insular Southeast Asia facilitates conversion and degradation of ecosystems and emits high amounts of carbon into the atmosphere. We analyzed the influence of peat soil and land cover distribution on the occurrence and characteristics of vegetation fires. Two years of satellite-based active fire detections over Peninsular Malaysia, Sumatra, Borneo and Java were examined together with land cover and peatland maps. Our results showed that fire occurrence nearly tripled (23,000 → 68,000) from a wet La Niña year (2008) to a drier El Niño year (2009). In both years, fires were concentrated in peatlands (in 2009 41% of fires vs. 10% of land area), and the majority of large-scale burning took place in peatlands. Variation in peatland land cover within the study area was noticed to create remarkable different fire regimes. Biomass burning in the intensely managed Sumatran peatlands was characterized by large-scale land clearance fires that took place annually to varying extent. The largely unmanaged degraded peatland ecosystems of Borneo, on the other hand, experienced very little fire activity in a wet year but were ravaged by large-scale wildfires when El Niño conditions arose. We conclude that fire regime characteristics in insular Southeast Asia are strongly connected to occurrence of peat soil and land management status. This leads to high variation of fire activity within this region both annually (depending on weather patters) and over longer time range (depending on land cover/management issues) and greatly complicates estimation of the effects of fires. 相似文献
892.
Chang-Qing Ke Dong Zhang Fu-Qiang Wang Shu-Xing Chen Christance Schmullius Wolfgang-Martin Boerner Hui Wang 《Regional Environmental Change》2011,11(1):161-173
Coastal zones provide habitat cores and corridors that maintain the diversity of entire landscapes, and they can form the
cornerstone elements of regional conservation strategies. Natural environmental driving factors and excessive anthropogenic
activities play important roles in coastal wetland change. Many studies have used remote sensing images to map and assess
coastal wetland change on local or regional scales. This paper aims to provide insight into coastal wetland change in the
Yancheng National Nature Reserve (YNNR) using remote sensing technology and landscape metrics analysis. The results reveal
that grass flat and reed areas have significantly decreased, whereas agriculture fields, aquaculture ponds and built-up areas
have continuously increased from 1988 to 2006. The spatial pattern of the coastal landscape has become fragmented and heterogeneous
under great pressure from rapid economic development and population growth. The wetland changes have important impacts on
natural habitat of the red-crowned cranes. The results of this study provide basic information that is required for developing
measures toward a sustainable management and conservation of the YNNR. 相似文献
893.
Andrea M. Bassi 《Regional Environmental Change》2011,11(2):285-295
Observing the many and varied reactions to the Kyoto Protocol, it becomes clear that different governments find themselves
in different contexts that eventually direct them toward taking dissimilar positions on energy issues. This paper, through
five integrated studies, investigates whether contextualizing energy issues is (are) relevant to support energy policy formulation
and evaluation and provides insights into how to operationalize the contextualization. Instead of considering the most widely
accepted tools currently used to assess and evaluate energy policy, this research proposes the utilization of a holistic framework
that incorporates social, economic and environmental factors as well as their relations to the energy sector to better contextualize
global, regional and national energy issues. This framework, which accounts for feedback loops, delays and non-linearity,
is applied to case studies to investigate the longer-term performance of selected energy policies. Results of the study indicate
the likely emergence of various unexpected side effects and elements of policy resistance over the medium and longer term
due to the interrelations existing between energy and society, economy and environment. Furthermore, while side effects and
unintended consequences may arise both within the energy sector and in the other sectors, they simultaneously influence society,
economy and environment. 相似文献
894.
Marc Gracia Nacima Meghelli Lluís Comas Javier Retana 《Regional Environmental Change》2011,11(2):349-358
The current state of Mediterranean mountain areas has been driven by two main factors: intense traditional human activity
and the dynamics of the ecosystem itself. In this study, we examine land-cover changes in a National Park in the Pyrenees
mountains (NE Iberian Peninsula), which was designated a protected area 55 years ago. First, we have analyzed spatio-temporal
changes in land-cover pattern and forest dynamics from 1957 to 2005. During this period, land-cover dynamics consisted of
two main processes: (i) expansion of the forest area and (ii) increasing cover of forests already present in 1957. To analyze
the role of the conservation level of the park, we have also compared the results obtained within the park with those of unprotected,
peripheral areas. In the two areas with different protection level, dense forests increased throughout the period because
of the reduction in forestry activities. The peripheral area showed a higher rate of forest-cover change from 1957 to 2005
compared to the National Park. This higher increase in forest cover in the peripheral area could be related to a higher proportion
in the National Park of screes and rocky areas and to the decline and transformation of forest activities in these peripheral,
lower elevation areas. 相似文献
895.
Climate change is one of the main factors that will affect biodiversity in the future and may even cause species extinctions. We suggest a methodology to derive a general relationship between biodiversity change and global warming. In conjunction with other pressure relationships, our relationship can help to assess the combined effect of different pressures to overall biodiversity change and indicate areas that are most at risk. We use a combination of an integrated environmental model (IMAGE) and climate envelope models for European plant species for several climate change scenarios to estimate changes in mean stable area of species and species turnover. We show that if global temperature increases, then both species turnover will increase, and mean stable area of species will decrease in all biomes. The most dramatic changes will occur in Northern Europe, where more than 35% of the species composition in 2100 will be new for that region, and in Southern Europe, where up to 25% of the species now present will have disappeared under the climatic circumstances forecasted for 2100. In Mediterranean scrubland and natural grassland/steppe systems, arctic and tundra systems species turnover is high, indicating major changes in species composition in these ecosystems. The mean stable area of species decreases mostly in Mediterranean scrubland, grassland/steppe systems and warm mixed forests. 相似文献
896.
Farming in higher latitudes is generally believed to benefit from a warmer climate due to extended growing season, reduced risk of frost, availability of more productive cultivars, and an opening potential of farming in northern locations. We analyzed the impact of climate change on production of cereals in Russia and found that this general perception of beneficiary effect of a warmer climate is unlikely to hold, primarily due to increasing risk of droughts in the most important agricultural areas of the country. Past impacts of droughts on food security throughout the twentieth century suggest that a number of adaptation options are available to mitigate the increasing risks of crop failure. We analyze the effectiveness of these measures in connection with a set of climate change projections, under two contrasting scenarios of interregional grain trade: “Fortress Market” and “Open Market.” 相似文献
897.
James S. Risbey 《Regional Environmental Change》2011,11(1):197-203
Water resources in Australia are sensitive to changes in rainfall. Ongoing droughts in south-west and south-east Australia are stressing water resources in the major cities and in agricultural regions. Climate change scenarios for Australia include reasonable prospects of long-term drying, which would exacerbate these issues. The dryer scenarios would entail major readjustments and costs on natural and human systems. 相似文献
898.
899.
Payments for Environmental Services in Latin America as a Tool for Restoration and Rural Development
Payments for Environmental Services (PES) can encourage projects that enhance restoration, production, and rural development.
When projects promote differentiated systems by paying farmers for the provision of services, the application of PES requires
evaluation of the environmental services provided by each system. We present evaluations of carbon stocks and biodiversity
in pure and mixed native tree plantations in Costa Rica. To illustrate how monetary values can be assigned, we discuss a project
that awarded PES to silvopastoral systems in Costa Rica, Nicaragua, and Colombia based on carbon stocks and biodiversity.
PES can promote positive environmental attitudes in farmers. Currently this project is being scaled up in Colombia based on
their positive experiences with PES as a tool to promote adoption. Compared to PES systems that include only one environmental
service, systems that incorporate bundling or layering of multiple services can make sustainable land uses more attractive
to farmers and reduce perverse incentives. 相似文献
900.
Policy and research issues in the framing and qualities of uncertainties in risks are analyzed, based on the assessments of
dioxin-like compounds (DLCs) and other ingredients in Baltic Sea fish, a high-profile case of governance. Risks are framed
broadly, to then focus on dioxins and beneficial fatty acids, fish consumption, human health, and science-management links.
Hierarchies of uncertainty (data, model, decision rule, and epistemic) and ambiguity (of values) are used to identify issues
of scientific and policy contestation and opportunities for resolving them. The associated complexity of risks is illustrated
by risk–benefit analyses of fish consumption and by evaluations of guideline values, highlighting value contents and policy
factors in presumably scientific decision criteria, and arguments used in multi-dimensional risk and benefit comparisons.
These comparisons pose challenges to narrow assessments centered, for e.g., on toxicants or on food benefits, and to more
many-sided and balanced risk communication and management. It is shown that structured and contextualized treatment of uncertainties
and ambiguities in a reflexive approach can inform balances between wide and narrow focus, detail and generality, and evidence
and precaution. 相似文献