共查询到20条相似文献，搜索用时 509 毫秒
1.
Recent temperature observations suggest a general warming trend that may be causing the range of tree species to shift to higher latitudes and altitudes. Since biotic interactions such as herbivory can change tree species composition, it is important to understand their contribution to vegetation changes triggered by climate change. To investigate the response of forests to climate change and herbivory by wild ungulates, we used the forest gap model ForClim v2.9.6 and simulated forest development in three climatically different valleys in the Swiss Alps. We used altitudinal transects on contrasting slopes covering a wide range of forest types from the cold (upper) to the dry (lower) treeline. This allowed us to investigate (1) altitudinal range shifts in response to climate change, (2) the consequences for tree species composition, and (3) the combined effect of climate change and ungulate herbivory. We found that ungulate herbivory changed species composition and that both basal area and stem numbers decreased with increasing herbivory intensity. Tree species responded differently to the change in climate, and their ranges did not change concurrently, thus causing a succession to new stand types. While climate change partially compensated for the reductions in basal area caused by ungulate herbivory, the combined effect of these two agents on the mix of the dominant species and forest type was non-compensatory, as browsing selectively excluded species from establishing or reaching dominance and altered competition patterns, particularly for light. We conclude that there is an urgent need for adaptive forest management strategies that address the joint effects of climate change and ungulate herbivory. 相似文献
2.
The Nooksack Indian Tribe (Tribe) inhabits the area around Deming, Washington, in the northwest corner of the state. The Tribe is dependent on various species of Pacific salmonids that inhabit the Nooksack River for ceremonial, commercial, and subsistence purposes. Of particular importance to the Tribe are spring Chinook salmon. Since European arrival, the numbers of fish that return to spawn have greatly diminished because of substantial loss of habitat primarily due to human-caused alteration of the watershed. Although direct counts are not available, it is estimated that native salmonid runs are less than 8 % of the runs in the late 1800’s. In addition, climate change has caused and will continue to cause an increase in winter flows, earlier snowmelt, decrease in summer baseflows, and an increase in water temperatures that exceed the tolerance levels, and in some cases lethal levels, of several Pacific salmonid species. The headwaters of the Nooksack River originate from glaciers on Mount Baker that have experienced significant changes over the last century due to climate change. Melt from the glaciers is a major source of runoff during the low-flow critical summer season, and climate change will have a direct effect on the magnitude and timing of stream flow in the Nooksack River. Understanding these changes is necessary to protect the Pacific salmonid species from the harmful effects of climate change. All nine salmonid species that inhabit the Nooksack River will be adversely affected by reduced summer flows and increased temperatures. The most important task ahead is the planning for, and implementation of, habitat restoration prior to climate change becoming more threatening to the survival of these important fish species. The Tribe has been collaboratively working with government agencies and scientists on the effects of climate change on the hydrology of the Nooksack River. The extinction of salmonids from the Nooksack River is unacceptable to the Tribe since it is dependent on these species and the Tribe is place-based and cannot relocate to areas where salmon will survive. 相似文献
3.
气候变化科学方面的几个最新认知 总被引：1，自引：0，他引：1
IPCC第六次评估报告（AR6）第一工作组报告主要从以下几个方面的进展提升了我们对气候系统变化、气候变化原因以及预估未来气候系统变化等方面的认知,对过去气候变化及其与人类活动的关系有了更加清晰、可靠的认识。综合多重证据评估指出,全球气候正经历着前所未有的变化;包括极端事件在内的归因进展已把人类活动对气候系统影响的认识从大气圈扩展到水圈、冰冻圈和生物圈,进一步强化了人类活动影响全球和区域气候的认识;有关区域气候变化信息的内容更加丰富,与各行业和敏感地区的气候变化影响联系更加紧密,使这些信息能更好地为气候变化风险评估和气候变化区域适应提供支持;气候模式和约束预估方法的发展以及对气候敏感度认识的深化,减少了未来不同排放情景下全球地表温度（Global Surface Temperature,GST)、海平面上升和海洋热含量的变化预估的不确定性。这份最新报告对我国提升气候变化研究水平和防灾减灾应对能力具有十分重要的指导意义。 相似文献
4.
Christopher R. Pyke 《Climatic change》2005,68(1-2):199-218
Combinations of habitat loss and climate change can alter the distribution of environmental conditions available to organisms. The magnitude and direction of these changes may have important implications for ecological processes and species persistence. This study explored the potential impacts of projected changes in climate and land-use for five fairy shrimp species (Crustacea: Anostraca) endemic to vernal pools in the Central Valley ecoregion of California, U.S.A. Scenarios describing habitat extent and climate were developed for 2040 and 2100 and compared to a 1990s baseline. Hydrologic conditions in vernal pools were found to be sensitive to projected climate changes, and, in the absence of habitat loss, warmer temperatures and greater winter precipitation would drive vernal pools toward longer, more frequent periods of inundation. However, existing biological reserves for three of the five species are biased toward drier areas and if unprotected habitat were lost, the net change in hydrologic conditions would be reversed with remaining habitat providing shorter, less frequent inundations. Species with unbiased representation in reserves do not show this reversal, and they have predictable shifts in hydrologic conditions. These results demonstrate the importance of biologically and climatically representative reserve systems under climate change and habitat loss. 相似文献
5.
Nicola Ranger St��phane Hallegatte Sumana Bhattacharya Murthy Bachu Satya Priya K. Dhore Farhat Rafique P. Mathur Nicolas Naville Fanny Henriet Celine Herweijer Sanjib Pohit Jan Corfee-Morlot 《Climatic change》2011,104(1):139-167
Managing risks from extreme events will be a crucial component of climate change adaptation. In this study, we demonstrate an approach to assess future risks and quantify the benefits of adaptation options at a city-scale, with application to flood risk in Mumbai. In 2005, Mumbai experienced unprecedented flooding, causing direct economic damages estimated at almost two billion USD and 500 fatalities. Our findings suggest that by the 2080s, in a SRES A2 scenario, an ??upper bound?? climate scenario could see the likelihood of a 2005-like event more than double. We estimate that total losses (direct plus indirect) associated with a 1-in-100 year event could triple compared with current situation (to $690?C$1,890 million USD), due to climate change alone. Continued rapid urbanisation could further increase the risk level. The analysis also demonstrates that adaptation could significantly reduce future losses; for example, estimates suggest that by improving the drainage system in Mumbai, losses associated with a 1-in-100 year flood event today could be reduced by as much as 70%.,We show that assessing the indirect costs of extreme events is an important component of an adaptation assessment, both in ensuring the analysis captures the full economic benefits of adaptation and also identifying options that can help to manage indirect risks of disasters. For example, we show that by extending insurance to 100% penetration, the indirect effects of flooding could be almost halved. We conclude that, while this study explores only the upper-bound climate scenario, the risk-assessment core demonstrated in this study could form an important quantitative tool in developing city-scale adaptation strategies. We provide a discussion of sources of uncertainty and risk-based tools could be linked with decision-making approaches to inform adaptation plans that are robust to climate change. 相似文献
6.
We explore the impact of future climate change on the risk of forest and grassland fires over Australia in January using a
high resolution regional climate model, driven at the boundaries by data from a transitory coupled climate model. Two future
emission scenarios (relatively high and relatively low) are used for 2050 and 2100 and four realizations for each time period
and each emission scenario are run. Results show a consistent increase in regional-scale fire risk over Australia driven principally
by warming and reductions in relative humidity in all simulations, under all emission scenarios and at all time periods. We
calculate the probability density function for the fire risk for a single point in New South Wales and show that the probability
of extreme fire risk increases by around 25% compared to the present day in 2050 under both relatively low and relatively
high emissions, and that this increases by a further 20% under the relatively low emission scenario by 2100. The increase
in the probability of extreme fire risk increases dramatically under the high emission scenario by 2100. Our results are broadly
in-line with earlier analyses despite our use of a significantly different methodology and we therefore conclude that the
likelihood of a significant increase in fire risk over Australia resulting from climate change is very high. While there is
already substantial investment in fire-related management in Australia, our results indicate that this investment is likely
to have to increase to maintain the present fire-related losses in Australia. 相似文献
7.
M. A. Esteve-Selma J. Martínez-Fernández I. Hernández-García J. P. Montávez J. J. López-Hernández J. F. Calvo 《Climatic change》2012,113(3-4):663-678
South-eastern Spain is a key area for assessing the effects of climate change on biodiversity since it presents an ecotone between the Mediterranean biome and the subtropical shrublands of arid lands. The forests of Tetraclinis articulata constitutes an especially relevant case. A species distribution model has been developed, regionalised climate change scenarios for South-eastern Spain were generated and expected changes in the suitability area of this species were estimated under B2 and A2 SRES scenarios for the time slice 2020–2050. Moreover, land use in the present and future potential habitat has been analysed. The high sensitivity of T. articulata is expressed not only as effects of climate change in the near future when compared to the present-day situation but also in the remarkable differences under scenarios B2 and A2. Under scenario B2 the suitable area for T. articulata would expand six-fold whereas under A2 the potential habitat would disappear from its present-day distribution and would move to a small area in the interior mountains. Under scenario B2 the future potential habitat in the coastal location would include enough area of shrublands, the main effective habitat of the species. Moreover, the present and future potential habitat partially overlaps, which facilitates the species migration. On the contrary, in the interior potential habitat the land use is less favourable for the effective habitat, the actual and future potential habitat do not overlap and the low dispersal capabilities of the species prevents natural migration to the interior to be expected. 相似文献
8.
Éva E. Plagányi Timothy D. Skewes Natalie A. Dowling Malcolm Haddon 《Climatic change》2013,119(1):181-197
Sustainable fisheries management into the future will require both understanding of and adaptation to climate change. A risk management approach is appropriate due to uncertainty in climate projections and the responses of target species. Management strategy evaluation (MSE) can underpin and support effective risk management. Climate change impacts are likely to differ by species and spatially. We use a spatial MSE applied to a multi-species data-poor sea cucumber/béche-de-mer fishery to demonstrate the utility of MSE to test the performance of alternative harvest strategies in meeting fishery objectives; this includes the ability to manage through climate variability and change, and meeting management objectives pertaining to resource status and fishery economic performance. The impacts of fishing relative to the impacts of climate change are distinguished by comparing future projection distributions relative to equivalent no-fishing no-climate-change trials. The 8 modelled species exhibit different responses to environmental variability and have different economic value. Status quo management would result in half the species falling below target levels, moderate risks of overall and local depletion, and significant changes in species composition. The three simple strategies with no monitoring (spatial rotation, closed areas, multi-species composition) were all successful in reducing these risks, but with fairly substantial decreases in the average profit. Higher profits (for the same risk levels) could only be achieved with strategies that included monitoring and hence adaptive management. Spatial management approaches based on adaptive feedback performed best overall. 相似文献
9.
In this paper we study an isolated high-mountain (Sierra Nevada, SE Iberian Peninsula) to identify the potential trends in
the habitat-suitability of five key species (i.e. species that domain a given vegetation type and drive the conditions for
appearance of many other species) corresponding to four vegetation types occupying different altitudinal belts, that might
result from a sudden climatic shift. We used topographical variables and downscaled climate warming simulations to build a
high-resolution spatial database (10 m) according to four different climate warming scenarios for the twenty-first century.
The spatial changes in the suitable habitat were simulated using a species distribution model, in order to analyze altitudinal
shifts and potential habitat loss of the key species. Thus, the advance and receding fronts of known occurrence locations
were computed by introducing a new concept named differential suitability, and potential patterns of substitution among the key species were established. The average mean temperature trend show an
increase of 4.8°C, which will induce the vertical shift of the suitable habitat for all the five key species considered at
an average rate of 11.57 m/year. According to the simulations, the suitable habitat for the key species inhabiting the summit
area, where most of the endemic and/or rare species are located, may disappear before the middle of the century. The other
key species considered show moderate to drastic suitable habitat loss depending on the considered scenario. Climate warming
should provoke a strong substitution dynamics between species, increasing spatial competition between both of them. In this
study, we introduce the application of differential suitability concept into the analysis of potential impact of climate change, forest management and environmental monitoring, and discuss
the limitations and uncertainties of these simulations. 相似文献
10.
IPCC第五次评估报告（AR5）第二工作组（WGII）报告认为,气候变化对世界上大部分区域的自然和人类系统的影响将进一步加剧,其对非洲最大的影响预计发生在半干旱的环境,增加现有的水资源可利用量和农业系统的压力;气候变化已导致北欧地区的谷物产量增加而南欧地区的产量降低,未来的变化将增加欧洲的灌溉需求;在亚洲的许多地区,气候变化将导致农业生产率下降;气候、大气CO2和海洋酸化的进一步变化预计将对大洋洲的水资源、海岸生态系统、基础设施、健康、农业和生物多样性产生实质性的影响;在北美,许多带来风险的气候压迫力的频率和强度将在未来几十年增加;中美洲和南美洲许多国家的持续高水平贫困导致了对气候变率和变化的高脆弱性;在北极,气候变化与非气候相关驱动在确定的物理、生物和社会经济风险上交互作用,变化率可能超过了社会系统适应的速率;在气候和非气候因素的影响下,小岛屿具有高度的脆弱性,同时,气候变暖将增加海洋生态系统的风险。 相似文献
11.
Ecosystem changes in floodplains could be a major issue during the twenty-first century as designated habitat areas are affected by climate change and floodplain management options. As part of the RegIS project, a Regional Impact Simulator has been developed to investigate these potential changes. This paper presents the methodologies and results of biodiversity metamodels used within the Regional Impact Simulator for two regions of the UK: East Anglia and North West England. Potential impacts and adaptations to future climate and socio-economic scenarios are analysed for three habitat types in floodplains (saltmarsh, coastal grazing marsh and fluvial grazing marsh) and selected species. An important finding is that management choices, which can be linked to socio-economic futures have a greater potential impact on habitat viability than climate change. The choices society makes will therefore be key to protection and conservation of biodiversity. The analyses also show that coastal grazing marsh is the most vulnerable habitat to sea-level rise, although there is a scope for substituting losses with fluvial grazing marsh. These results indicate that these methods provide a useful approach for assessing potential biodiversity changes at the regional scale, including the effect of different policies. 相似文献
12.
Models that address the impacts of climate change on forests are reviewed at four levels of biological organization: global, regional or landscape, community, and tree. The models are compared for their ability to assess changes in fluxes of biogenic greenhouse gases, land use, patterns of forest type or species composition, forest resource productivity, forest health, biodiversity, and wildlife habitat. No one model can address all of these impacts, but landscape transition models and regional vegetation and land-use models have been used to consider more impacts than the other models. The development of landscape vegetation dynamics models of functional groups is suggested as a means to integrate the theory of both landscape ecology and individual tree responses to climate change. Risk assessment methodologies can be adapted to deal with the impacts of climate change at various spatial and temporal scales. Four areas of research needing additional effort are identified: (1) linking socioeconomic and ecologic models; (2) interfacing forest models at different scales; (3) obtaining data on susceptibility of trees and forest to changes in climate and disturbance regimes; and (4) relating information from different scales.The U.S. Government right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged.Managed by Martin Marietta Energy Systems, Inc., for the U.S. Department of Energy under contract DE-AC05-84OR21400. 相似文献
13.
Many endangered species persist as a series of isolated populations, with some populations more genetically diverse than others. If climate change disproportionately threatens the most diverse populations, the species’ ability to adapt (and hence its long-term viability) may be affected more severely than would be apparent by its numerical reduction. In the present study, we combine genetic data with modelling of species distributions under climate change to document this situation in an endangered lizard (Eulamprus leuraensis) from montane southeastern Australia. The species is known from only about 40 isolated swamps. Genetic diversity of lizard populations is greater in some sites than others, presumably reflecting consistently high habitat suitability over evolutionary time. Species distribution modelling suggests that the most genetically diverse populations are the ones most at risk from climate change, so that global warming will erode the species’ genetic variability faster than it curtails the species’ geographic distribution. 相似文献
14.
Global Climate Change and Tropical Forest Genetic Resources 总被引：4，自引：0，他引：4
Global climate change may have a serious impact on genetic resources in tropical forest trees. Genetic diversity plays a critical role in the survival of populations in rapidly changing environments. Furthermore, most tropical plant species are known to have unique ecological niches, and therefore changes in climate may directly affect the distribution of biomes, ecosystems, and constituent species. Climate change may also indirectly affect plant genetic resources through effects on phenology, breeding systems, and plant-pollinator and plant seed disperser interactions, and may reduce genetic diversity and reproductive output. As a consequence, population densities may be reduced leading to reduction in genetic diversity through genetic drift and inbreeding. Tropical forest plants may respond to climate change through phenotypic plasticity, adaptive evolution, migration to suitable site, or extinction. However, the potential to respond is limited by a rapid pace of change and the non-availability of alternate habitats due to past and present trends of deforestation. Thus climate change may result in extinction of many populations and species. Our ability to estimate the precise response of tropical forest ecosystems to climate change is limited by lack of long-term data on parameters that might be affected by climate change. Collection of correlative data from long-term monitoring of climate as well as population and community responses at selected sites offer the most cost-effective way to understand the effects of climate change on tropical tree populations. However, mitigation strategies need to be implemented immediately. Because many effects of climate change may be similar to the effects of habitat alteration and fragmentation, protected areas and buffer zones should be enlarged, with an emphasis on connectivity among conserved landscapes. Taxa that are likely to become extinct should be identified and protected through ex situ conservation programs. 相似文献
15.
Although climate change is an urgent problem, behavioural and policy responses have not yet been sufficient to either reduce the volume of greenhouse gas emissions or adapt to a disrupted climate system. Significant efforts have been made to raise public awareness of the dangers posed by climate change. One reason why these efforts might not be sufficient is rooted in people’s need to feel efficacy to solve complex problems; the belief that climate change is unstoppable might thwart action even among the concerned. This paper tests for the effect of fatalistic beliefs on behavioural change and willingness to pay to address climate change using two cross-national surveys representing over 50,000 people in 48 nations.
Key policy insights
The perception that climate change poses a risk or danger increases the likelihood of behavioural change and willingness to pay to address climate change.
The belief that climate change is unstoppable reduces the behavioural and policy response to climate change and moderates risk perception.
Communicators and policy leaders should carefully frame climate change as a difficult, yet solvable, problem to circumvent fatalistic beliefs.
16.
Increasing greenhouse gas emissions are projected to raise global average surface temperatures by 3?–4 °C within this century, dramatically increasing the extinction risk for terrestrial and freshwater species and severely disrupting ecosystems across the globe. Limiting the magnitude of warming and its devastating impacts on biodiversity will require deep emissions reductions that include the rapid, large-scale deployment of low-carbon renewable energy. Concerns about potential adverse impacts to species and ecosystems from the expansion of renewable energy development will play an important role in determining the pace and scale of emissions reductions and hence, the impact of climate change on global biodiversity. Efforts are underway to reduce uncertainty regarding wildlife impacts from renewable energy development, but such uncertainty cannot be eliminated. We argue the need to accept some and perhaps substantial risk of impacts to wildlife from renewable energy development in order to limit the far greater risks to biodiversity loss owing to climate change. We propose a path forward for better reconciling expedited renewable energy development with wildlife conservation in a warming world. 相似文献
17.
James R. Hatten Thomas R. Batt Patrick J. Connolly Alec G. Maule 《Climatic change》2014,124(1-2):427-439
We evaluated the potential effects of two climate change scenarios on salmonid habitats in the Yakima River by linking the outputs from a watershed model, a river operations model, a two-dimensional (2D) hydrodynamic model, and a geographic information system (GIS). The watershed model produced a discharge time series (hydrograph) in two study reaches under three climate scenarios: a baseline (1981–2005), a 1-°C increase in mean air temperature (plus one scenario), and a 2-°C increase (plus two scenario). A river operations model modified the discharge time series with Yakima River operational rules, a 2D model provided spatially explicit depth and velocity grids for two floodplain reaches, while an expert panel provided habitat criteria for four life stages of coho and fall Chinook salmon. We generated discharge-habitat functions for each salmonid life stage (e.g., spawning, rearing) in main stem and side channels, and habitat time series for baseline, plus one (P1) and plus two (P2) scenarios. The spatial and temporal patterns in salmonid habitats differed by reach, life stage, and climate scenario. Seventy-five percent of the 28 discharge-habitat responses exhibited a decrease in habitat quantity, with the P2 scenario producing the largest changes, followed by P1. Fry and spring/summer rearing habitats were the most sensitive to warming and flow modification for both species. Side channels generally produced more habitat than main stem and were more responsive to flow changes, demonstrating the importance of lateral connectivity in the floodplain. A discharge-habitat sensitivity analysis revealed that proactive management of regulated surface waters (i.e., increasing or decreasing flows) might lessen the impacts of climate change on salmonid habitats. 相似文献
18.
Jeremy S. Littell Elaine E. Oneil Donald McKenzie Jeffrey A. Hicke James A. Lutz Robert A. Norheim Marketa M. Elsner 《Climatic change》2010,102(1-2):129-158
Climatic change is likely to affect Pacific Northwest (PNW) forests in several important ways. In this paper, we address the role of climate in four forest ecosystem processes and project the effects of future climatic change on these processes across Washington State. First, we relate Douglas-fir growth to climatic limitation and suggest that where Douglas-fir is currently water-limited, growth is likely to decline due to increased summer water deficit. Second, we use existing analyses of climatic controls on tree species biogeography to demonstrate that by the mid twenty-first century, climate will be less suitable for key species in some areas of Washington. Third, we examine the relationships between climate and the area burned by fire and project climatically driven regional and sub-regional increases in area burned. Fourth, we suggest that climatic change influences mountain pine beetle (MPB) outbreaks by increasing host-tree vulnerability and by shifting the region of climate suitability upward in elevation. The increased rates of disturbance by fire and mountain pine beetle are likely to be more significant agents of changes in forests in the twenty-first century than species turnover or declines in productivity, suggesting that understanding future disturbance regimes is critical for successful adaptation to climate change. 相似文献
19.
This paper reviews the potential vulnerability of solar energy systems to future extreme event risks as a consequence of climate change. We describe the three main technologies likely to be used to harness sunlight—thermal heating, photovoltaic (PV), and concentrating solar power (CSP)—and identify critical climate vulnerabilities for each one. We then compare these vulnerabilities with assessments of future changes in mean conditions and extreme event risk levels. We do not identify any vulnerabilities severe enough to halt development of any of the technologies mentioned, although we do find a potential value in exploring options for making PV cells more heat-resilient and for improving the design of cooling systems for CSP. 相似文献
20.
Climate change in California is altering habitat conditions for many species and exacerbating stress from other factors such
as alien invasive species, pollution, and habitat fragmentation. However, the current legal and planning framework for species
protection does not explicitly take climate change into account. The regulatory framework is primarily reactive, kicking in
only after species’ health is gravely threatened. Neither federal nor state regulations require forward-looking, climate-sensitive
species or ecosystem protection plans. Habitat planning is poorly funded and often piecemeal. In this context, the wrong lands
may be protected, with development allowed to occur in areas that would be most beneficial for species conservation in the
future. A more forward-looking approach to habitat conservation is needed, one based on a statewide strategy to identify and
protect critical habitat areas, including corridors to enable species migration. The approach would also require development
of assessment indicators and assistance strategies not dependent on current habitat structure, and a governance structure
to implement regular, periodic updates of management plans in relation to agreed-upon performance indicators. Such a strategy
should integrate habitat conservation planning with other state and regional plans and objectives, such as for transportation
infrastructure, urban development, and mitigation of climate change. 相似文献