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1.
Extant species of Muridae occupy a wide array of habitats and have diverse dietary habits. Consequently, their dental microwear patterns represent a potential clue to better understand the paleoecology of their extinct relatives, which are abundant in many Old World Neogene localities. In this study, dental microwear is investigated for specimens of 17 extant species of murine and deomyine rodents in order to test the reliability of this method and infer dietary preferences on the fossil species Saïdomys afarensis. This extinct form comes from a mid-Pliocene site (AL 327) located at the Hadar Formation (Ethiopia) known to have delivered many hominid specimens of Australopithecus afarensis. A significant correlation between microwear patterns and diet is detected. Thus, grass, fruit, and insect eaters display, respectively, high amounts of fine scratches, wide scratches, and large pits. Moreover, some aspects of the paleoecology of S. afarensis, including feeding habits, could be assessed in regard to its dental microwear pattern. Indeed, it probably had feeding habits similar to that of living grass eaters. These results concur with the presence of open to woodland areas covered by an herbaceous vegetal layer, including monocotyledons, in the vicinity of this mid-Pliocene locality. 相似文献
2.
Today and in the Tertiary, the geographical distribution of castorids is limited throughout all of the northern continents.
Fossils of the Castoridae genus Steneofiber are abundant in many localities of Eurasia from the late Oligocene to Pliocene period. Recently, Steneofiber fossils were discovered in two localities of northern Thailand, Mae Moh and Chiang Muan coal mines, in layers of late middle
Miocene age. These discoveries represent the first records of castorids from Southeast Asia and correspond to their southernmost
known range. The focus of this study is to describe this new Thai species of Steneofiber and to define its wear stages from the molar occlusal surfaces by using micro-CT scan analysis. The CT scan technique permits
the analysis of the virtual occlusal surface changes from wear, allowing easier comparison to related species of Steneofiber cheek teeth without destroying the teeth. The new species, Steneofiber siamensis n. sp., can be distinguished from the other species of Steneofiber by several distinct characters, longer mesostriid on p4, presence of premesostria and metastria on P4, which are smaller
than most of the other known species. The occurrence of this new castorid also supports a subtropical to tropical paleoclimate
for these two localities of northern Thailand. 相似文献
3.
Dental microwear in relation to changes in the direction of mastication during the evolution of Myodonta (Rodentia,Mammalia) 总被引:1,自引:1,他引:1
Observations of dental microwear are used to analyse the correlation between changes in molar tooth crown morphology and the
direction of masticatory movement during the evolution of Myodonta (Rodentia, Mammalia). The studied sample includes 36 specimens
representing both superfamilies of Myodonta (Muroidea and Dipodoidea) spanning 16 dipodoid and 9 muroid species. Microscopic
scratches on occlusal surfaces resulting from contact between opposite teeth during mastication are analysed. Using these
features, we determine the direction of masticatory movements. Microwear patterns display diverse orientations among Dipodoidea:
oblique in Sicistinae, Euchoreutinae and Zapodinae, propalinal in Dipodinae and intermediary in Allactaginae. Similarly, Muroidea
exhibit the following orientations: oblique in Cricetinae and propalinal in Arvicolinae, Cricetomyinae, Gerbillinae and Murinae.
These various chewing types illustrate different evolutionary grades within the superfamilies. Acquisition of the antero-posterior
masticatory movement in Dipodoidea is related to flattening of the molar occlusal surface. However, in some muroid subfamilies,
this direction of mastication is associated with low-crowned and cuspidate molars (Cricetomyinae, Murinae). 相似文献
4.
This article examines farmers’ livelihood responses and vulnerability to climate variability and other stressors in Morogoro, Tanzania, to understand their implications for adaptation to climate change by agricultural households in developing world more generally. In Morogoro, agricultural households have extended cultivation, intensified agriculture, diversified livelihoods and migrated to gain access to land, markets and employment as a response to climatic and other stressors. Some of these responses have depleted and degraded natural resources such as forest, soil and water resources, which will complicate their living with climate change in the future. This will be particularly problematic to vulnerable groups such as women, children and pastoralists who have limited access to employment, markets and public services. In this light, fair adaptation to climate change by agricultural households in Morogoro and elsewhere in developing countries requires several complementary responses. Adaptation efforts should involve effective governance of natural resources because they function as safety nets to vulnerable groups. In addition, strengthening of national markets by infrastructure investments and institutional reforms is needed to give incentives to intensification and diversification in agriculture. Market participation also demands enhancement of human capital by public programs on health, education and wellbeing. 相似文献
5.
This article re-conceptualizes Climate Policy Integration (CPI) in the land use sector to highlight the need to assess the level of integration of mitigation and adaptation objectives and policies to minimize trade-offs and to exploit synergies. It suggests that effective CPI in the land use sector requires i) internal climate policy coherence between mitigation and adaptation objectives and policies; ii) external climate policy coherence between climate change and development objectives; iii) vertical policy integration to mainstream climate change into sectoral policies and; iv) horizontal policy integration by overarching governance structures for cross-sectoral coordination. This framework is used to examine CPI in the land use sector of Indonesia. The findings indicate that adaptation actors and policies are the main advocates of internal policy coherence. External policy coherence between mitigation and development planning is called for, but remains to be operationalized. Bureaucratic politics has in turn undermined vertical and horizontal policy integration. Under these circumstances it is unlikely that the Indonesian bureaucracy can deliver strong coordinated action addressing climate change in the land use sector, unless sectoral ministries internalize a strong mandate on internal and external climate policy coherence and find ways to coordinate policy action effectively. 相似文献
6.
Shimpei Iwasaki Bam Haja Nirina Razafindrabe Rajib Shaw 《Mitigation and Adaptation Strategies for Global Change》2009,14(4):339-355
Climate change combined with human activities poses significant risks to people’s livelihood especially in developing countries.
Adaptation at the community level is of crucial importance in enabling them to respond to the direct and indirect effects
of changes in climate. In a case study of fishing communities in Chilika lagoon, India, the focus is made on understanding
climate change adaptation at the community level and scaling it up into the policy perspective through application of Sustainable
Livelihood Approach. This article challenges the research and policy community to encourage the identification of locally
negative constraints and positive strengths toward climate resilient communities in rural areas.
相似文献
Rajib ShawEmail: |
7.
The double trade-off between adaptation and mitigation for sea level rise: an application of FUND 总被引:4,自引:2,他引:4
Richard S. J. Tol 《Mitigation and Adaptation Strategies for Global Change》2007,12(5):741-753
This paper studies the effects of adaptation and mitigation on the impacts of sea level rise. Without adaptation, the impact
of sea level rise would be substantial, almost wiping out entire countries by 2100, although the globally aggregate effect
is much smaller. Adaptation would reduce potential impacts by a factor 10–100. Adaptation would come at a minor cost compared
to the damage avoided. As adaptation depends on socio-economic status, the rank order of most vulnerable countries is different
than the rank order of most exposed countries. Because the momentum of sea level rise is so large, mitigation can reduce impacts
only to a limited extent. Stabilising carbon dioxide concentrations at 550 ppm would cut impacts in 2100 by about 10%. However,
the costs of emission reduction lower the avoided impacts by up to 25% (average 10%). This is partly due to the reduced availability
of resources for adaptation, and partly due to the increased sensitivity to wetland loss by adaptation.
相似文献
Richard S. J. TolEmail: |
8.
Recent interest in sustainable forest management planning in the Yukon has coincided with growing public awareness of climate
change, providing an opportunity to explore how forestry plans are incorporating climate change. In this paper, the Strategic
Forest Management Plans for the Champagne and Aishihik First Nations Traditional Territory (CATT) and the Teslin Tlingit Traditional
Territory (TTTT) are examined for evidence of adaptation to climate change. For each plan, management policies and practices
that are also recognized as ways to adapt to climate change are identified to provide information on the incremental costs
and benefits of additional adaptation efforts. A typology for classifying sustainable forest management plans according to
how they address climate change is proposed and applied to the CATT and TTTT plans. This typology, which may be useful to
any future retrospective assessments on how successful these or other sustainable forest management plans have been in addressing
and managing the risks posed by climate change, consists of a matrix that categorizes plans into one of four types; (1) proactive-direct,
(2) proactive-indirect, (3) reactive-direct, and (4) reactive-indirect. Neither of the plans available for the southern Yukon
explicitly identifies climate change vulnerabilities and actions that will be taken to reduce those vulnerabilities and manage
risks. However, both plans have incorporated some examples of ‘best management practices’ for sustainable forest management
that are also consistent with appropriate climate adaptation responses. Even in a jurisdiction facing rapid ecological changes
driven by climate change, where there is a relatively high level of awareness of climate change and its implications, forestry
planning processes have yet to grapple directly with the risks that climate change may pose to the ability of forest managers
to achieve the stated goals and objectives of sustainable forest management plans.
相似文献
J. L. InnesEmail: |
9.
The relationship between adaptation and mitigation in managing climate change risks: a regional response from North Central Victoria,Australia 总被引:1,自引:0,他引:1
Roger N. Jones Paul Dettmann Geoff Park Maureen Rogers Terry White 《Mitigation and Adaptation Strategies for Global Change》2007,12(5):685-712
This two-part paper considers the complementarity between adaptation and mitigation in managing the risks associated with
the enhanced greenhouse effect. Part one reviews the application of risk management methods to climate change assessments.
Formal investigations of the enhanced greenhouse effect have produced three generations of risk assessment. The first led
to the United Nations Intergovernmental Panel on Climate Change (IPCC), First Assessment Report and subsequent drafting of
the United Nations Framework Convention on Climate Change. The second investigated the impacts of unmitigated climate change
in the Second and Third IPCC Assessment Reports. The third generation, currently underway, is investigating how risk management
options can be prioritised and implemented. Mitigation and adaptation have two main areas of complementarity. Firstly, they
each manage different components of future climate-related risk. Mitigation reduces the number and magnitude of potential
climate hazards, reducing the most severe changes first. Adaptation increases the ability to cope with climate hazards by
reducing system sensitivity or by reducing the consequent level of harm. Secondly, they manage risks at different extremes
of the potential range of future climate change. Adaptation works best with changes of lesser magnitude at the lower end of
the potential range. Where there is sufficient adaptive capacity, adaptation improves the ability of a system to cope with
increasingly larger changes over time. By moving from uncontrolled emissions towards stabilisation of greenhouse gases in
the atmosphere, mitigation limits the upper part of the range. Different activities have various blends of adaptive and mitigative
capacity. In some cases, high sensitivity and low adaptive capacity may lead to large residual climate risks; in other cases,
a large adaptive capacity may mean that residual risks are small or non-existent. Mitigative and adaptive capacity do not
share the same scale: adaptive capacity is expressed locally, whereas mitigative capacity is different for each activity and
location but needs to be aggregated at the global scale to properly assess its potential benefits in reducing climate hazards.
This can be seen as a demand for mitigation, which can be exercised at the local scale through exercising mitigative capacity.
Part two of the paper deals with the situation where regional bodies aim to maximise the benefits of managing climate risks
by integrating adaptation and mitigation measures at their various scales of operation. In north central Victoria, Australia,
adaptation and mitigation are being jointly managed by a greenhouse consortium and a catchment management authority. Several
related studies investigating large-scale revegetation are used to show how climate change impacts and sequestration measures
affect soil, salt and carbon fluxes in the landscape. These studies show that trade-offs between these interactions will have
to be carefully managed to maximise their relative benefits. The paper concludes that when managing climate change risks,
there are many instances where adaptation and mitigation can be integrated at the operational level. However, significant
gaps between our understanding of the benefits of adaptation and mitigation between local and global scales remain. Some of
these may be addressed by matching demands for mitigation (for activities and locations where adaptive capacity will be exceeded)
with the ability to supply that demand through localised mitigative capacity by means of globally integrated mechanisms. 相似文献
10.
Human adaptation to climate change: a review of three historical cases and some general perspectives
To study mitigation and adaptation to climate change, social scientists have drawn on different approaches, particularly sociological approaches to the future and comparative history of past societies. These two approaches frame the social and temporal boundaries of decision-making collectivities in different ways. A consideration of the responses to climate variability in three historical cases, the Classic Maya of Mexico and Central America, the Viking settlements in Greenland, and the US Dust Bowl, shows the value of integrating these two approaches. 相似文献
11.
Urban areas are increasingly seen as having distinct need for climate adaptation. Further, as resources are limited, it is essential to prioritize adaptation actions. At the municipal scale, we suggest that priorities be placed where there is a gap between adaption need and existing adaptation effort. Taking Seattle, USA, as an example, we present this gap in terms of four categories of adaptation options (no-regret, primary, secondary, and tertiary) for the three primary urban hazards—flooding, heat wave, and drought. To do so, we first establish current adaptation need by identifying and categorizing adaptation options. Next, we consider for each option the number of hazards addressed and benefit to and beyond climate adaptation, the projected magnitude of the hazards addressed, the projection’s uncertainty, and the required scale and irreversibility of investment. Third, we assessed Seattle’s current adaptation efforts by reviewing adaptation plans and related materials. Finally, we identify the distance or “gap” as the proportion of adaptation options not identified by existing adaptation plans.For Seattle, we categorized seven options as no-regret adaptation, five as primary, two as secondary, and three as tertiary. Each level’s adaptation gap highlights significant opportunities to take steps to reduce climate risks in key areas. 相似文献
12.
In the wake of the failures to date of well-publicized multilateral and multi-sectoral mitigation efforts to control greenhouse gases, attention is now increasingly focused on the effectiveness and capacity of national and sub-national level sectoral plans, including forestry, to usher in a new era of adaptation efforts. In Canada, the government of British Columbia spent several years developing its Future Forest Ecosystems Initiative as part of a larger climate change response strategy in the forest sector. Similarly, in the United States, wildfire related events have led to climate change inspired efforts by individual states (e.g., Alaska, California) and the US Forest Service has recently undertaken plans to incorporate climate change considerations in national forest planning beginning with the National Road Map for Responding to Climate Change. This paper highlights a number of shortcomings with both these national and sub-national strategies with respect to the relationships existing between governance, forestry and climate change. It proposes incorporating considerations of governance mechanisms directly into forest sector planning and the need to assess not only natural system level changes but also the extent to which new problems can be dealt with by ‘old’ or ‘new’ governance arrangements. 相似文献
13.
Toward an integrated analysis of mitigation and adaptation: some preliminary findings 总被引:4,自引:0,他引:4
Thomas J. Wilbanks Paul Leiby Robert Perlack J. Timothy Ensminger Sherry B. Wright 《Mitigation and Adaptation Strategies for Global Change》2007,12(5):713-725
Between 1999 and 2003, the Oak Ridge National Laboratory (ORNL) made a preliminary effort to integrate an analysis of mitigation
and adaptation to climate change impact vulnerabilities in two ways: top-down and bottom-up. This paper briefly describes
these early experiments and summarizes their findings, both about climate change vulnerability reduction and about the challenges
of integrated analysis, expanding upon results previously reported [Wilbanks et al. (Environment 45/5:28–38, 2003); ORNL (Integrated analysis of mitigation and adaptation as responses to concerns about impacts of global climate change,
ORNL Working paper 2003); ORNL and CUSAT 2003; Wilbanks 2005].
The U.S Government’s right to retain a non-exclusive, royalty-free license in and to any copyright is acknowledged 相似文献
14.
Burrows play an important role for many species, providing them with shelter and access to food resources. For subterranean
rodents, living underground imposes constraints on morphology and physiology. The convergence in burrow architecture among
subterranean rodents has been related to the energy demands imposed by the cost of constructing an entire system. The low
frequency of tunnels with downward angles steeper than 40° appears to be a common feature in burrow design. In the subterranean
habitat, movements through the soil are expensive and gravity can exert important restrictions on digging energetics when
individuals push out the soil removed in steeper digging angles. The aim of this study was to determine the effect of digging
angle on digging energetics in Ctenomys talarum. The mass of the removed soil and burrowing speed were similar while digging metabolic rate and net cost of transport were
higher in individuals digging in tunnels with angles >40° than in those digging tunnels with angles <40°. The cost of constructing
a burrow in the horizontal plane differed by 20% from others in which the natural representation of tunnels >40° was considered.
Even given that tunnels >40° represented only 6% of the total burrow length, burrow architecture appears to be constrained
by the high energetic cost of constructing in steeper angles. 相似文献
15.
Issues in developing a capacity for integrated analysis of mitigation and adaptation 总被引:2,自引:0,他引:2
As policymakers and stakeholders increasingly consider relative merits and complementarities of climate change mitigation and adaptation strategies, it is important to improve analytical capacities to support this process. Because a single analytical approach is unlikely to fit all needs, this paper explores potentials for an integrated analytical framework that incorporates both top–down and bottom–up approaches. 相似文献
16.
The rains are disappointing us: dynamic vulnerability and adaptation to multiple stressors in the Afram Plains, Ghana 总被引:3,自引:0,他引:3
Lisa Westerhoff Barry Smit 《Mitigation and Adaptation Strategies for Global Change》2009,14(4):317-337
This paper builds on work on the dynamics of vulnerability and multiple stressors through a case study in the Afram Plains
of the Eastern region in Ghana. A vulnerability framework is applied in the community of Mimkyemfre to identify and explain
the multiple underlying political, socioeconomic and environmental forces that influence the ways in which people are exposed
and sensitive to climate, and their capacities to adapt to changing conditions. The results of the study indicate that the
community experiences a range of biophysical and socioeconomic conditions that contribute to its vulnerability. Vulnerability
was found to change over time and in some cases was cyclical, in that certain actions taken for the purposes of adaptation
were found to exacerbate existing vulnerabilities. Processes of vulnerability were also found to occur at several scales and
were experienced unevenly at the community level. The findings of this assessment have important implications for the design
and implementation of successful adaptation initiatives, both in Africa and elsewhere. In particular, they demonstrate the
need to understand the social, economic and institutional challenges to development as a basis for any contemplation of adaptation
to climate change. 相似文献
17.
气候变化问题日益凸显。应对和适应气候变化刻不容缓。然而,短期内无法有效减缓气候变化产生的不利影响。因此,有必要针对不同领域制定相应的适应措施来提高人们对气候变化的适应能力。北京作为人口众多的大城市及我国的缺水城市之一,气候变化无疑将加剧水资源的供需矛盾。本文针对北京市水资源现状及气候变化对北京市水资源领域已经形成的影响,从自然、工程、政策制度三个角度探讨了北京市水资源领域适应气候变化可采取的对策及保障措施。 相似文献
18.
H. G. Thomas M. Scantlebury D. Swanepoel P. W. Bateman N. C. Bennett 《Die Naturwissenschaften》2013,100(11):1023-1030
Sociality in mole rats has been suggested to have evolved as a response to the widely dispersed food resources and the limited burrowing opportunities that result from sporadic rainfall events. In the most arid regions, individual foraging efficiency is reduced, and energetic constraints increase. In this study, we investigate seasonal differences in burrow architecture of the social Cryptomys hottentotus hottentotus in a mesic region. We describe burrow geometry in response to seasonal weather conditions for two seasons (wet and dry). Interactions occurred between seasons and colony size for the size of the burrow systems, but not the shape of the burrow systems. The fractal dimension values of the burrow systems did not differ between seasons. Thus, the burrow complexity was dependent upon the number of mole rats present in the social group. 相似文献
19.
Preety M. Bhandari Suruchi Bhadwal Ulka Kelkar 《Mitigation and Adaptation Strategies for Global Change》2007,12(5):919-933
India occupies 2.4% of the world’s geographical area with a large percentage of its land under agriculture. About 228 Million
hectares (Mha) of its geographical area (nearly 69%) fall within the dryland (arid, semi-arid and dry sub-humid) region. Of
the total cultivated area of 142 Mha, major part of agriculture in the country is rainfed, extending to over 97 Mha and constituting
nearly 68% of the net cultivated area, therefore making the agricultural sector vulnerable and exposed to the vagaries of
weather conditions. Climate change adds to this dimension of stress. A strong need is felt for targeting programmes in these
areas that address issues related to employing suitable soil and water conservation measures. In this context this paper seeks
to examine the case for watershed development as an adaptive strategy. An examination of the possibility of fortifying the
existing programme with a view to adapting to expected changes in climate in future is undertaken. Also, the possibility of
watershed development integrating into a suitable mitigation strategy for the country is assessed.
相似文献
Preety M. BhandariEmail: |
20.
The value of indigenous knowledge in climate change mitigation and adaptation strategies in the African Sahel 总被引:6,自引:0,他引:6
A. Nyong F. Adesina B. Osman Elasha 《Mitigation and Adaptation Strategies for Global Change》2007,12(5):787-797
Past global efforts at dealing with the problem of global warming concentrated on mitigation, with the aim of reducing and
possibly stabilizing greenhouse gas (GHG) concentrations in the atmosphere. With the slow progress in achieving this, adaptation
was viewed as a viable option to reduce the vulnerability to the anticipated negative impacts of global warming. It is increasingly
realized that mitigation and adaptation should not be pursued independent of each other but as complements. This has resulted
in the recent calls for the integration of adaptation into mitigation strategies. However, integrating mitigation and adaptation
into climate change concerns is not a completely new idea in the African Sahel. The region is characterized by severe and
frequent droughts with records dating back into centuries. The local populations in this region, through their indigenous
knowledge systems, have developed and implemented extensive mitigation and adaptation strategies that have enabled them reduce
their vulnerability to past climate variability and change, which exceed those predicted by models of future climate change.
However, this knowledge is rarely taken into consideration in the design and implementation of modern mitigation and adaptation
strategies. This paper highlights some indigenous mitigation and adaptation strategies that have been practiced in the Sahel,
and the benefits of integrating indigenous knowledge into formal climate change mitigation and adaptation strategies. Incorporating
indigenous knowledge can add value to the development of sustainable climate change mitigation and adaptation strategies that
are rich in local content, and planned in conjunction with local people. 相似文献