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1.
In order to assess agricultural adaptation to climate impacts, new methodologies are needed. The translog distance function allows assessing interactions between different factors, and hence the influence of management on climate impacts. The Farm Accountancy Data Network provides extensive data on farm characteristics of farms throughout the EU15 (i.e. the 15 member states of the European Union before the extension in 2004). These data on farm inputs and outputs from 1990−2003 are coupled with climate data. As climate change is not the only change affecting European agriculture, we also include effects of subsidies and other changes on inputs and outputs of farms throughout Europe. We distinguish several regions and empirically assess (1) climate impacts on farm inputs and outputs in different regions and (2) interactions between inputs and other factors that contribute to the adaptation to these impacts. Changes in production can partly be related to climatic variability and change, but also subsidies and other developments (e.g. technology, markets) are important. Results show that impacts differ per region, and that ‘actual impacts’ cannot be explicitly separated into ‘potential impacts’ and ‘adaptive capacity’ as often proposed for vulnerability assessment. Farmers adapt their practices to prevailing conditions and continuously adapt to changing conditions. Therefore, ‘potential impacts’ will not be observed in practice, leaving it as a mainly theoretical concept. Factors that contribute to the adaptation also differ per region. In some regions more fertilizers or more irrigation can mitigate impacts, while in other regions this amplifies impacts. To project impacts of future climate change on agriculture, current farm management strategies and their influence on current production should be considered. This clearly asks for improved integration of biophysical and economic models.  相似文献   

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3.
The field of climate change is full of uncertainties that are limiting strategic disaster risk reduction planning. In this paper, however, we argued that there is lot to do before we get our hands on reliable estimates of future climate change impacts. It includes bringing together different stakeholders in a framework suggested in this paper, developing case studies that reflect long-term local impacts of climate change, capacity building of local stakeholders that enables them to take decisions under uncertainty etc. We proposed a simple scheme that brings together climate, disaster and policy community together to start a dialogue in a run-up to understanding wider aspects of long-term risk reduction at local level. Strategic thinking, which has only been restricted to national and regional planning to date, needs to be inculcated in local level disaster risk reduction and policy personnel as well. There is a need to move from the attitude of considering local level players as ‘implementers’ to ‘innovators’ for which developing a network of self learning and evolving organizations are required at the local level.  相似文献   

4.
Previous attempts to determine palaeoenvironmental preferences in dinosaurs have generally been qualitative assessments based upon data from restricted geographical areas. Here, we use a global database of Cretaceous herbivorous dinosaurs to identify significant associations between clades and broad palaeoenvironmental categories (‘terrestrial’, ‘coastal’, ‘marine’). Nodosaurid ankylosaurs and hadrosaurids show significant positive associations with marine sediments, while marginocephalians (Ceratopsia, Pachycephalosauria), saurischians (herbivorous theropods, Sauropoda) and ankylosaurid ankylosaurs are significantly positively associated with terrestrial sediments. These results provide quantitative support for the hypothesis that some clades (Nodosauridae, Hadrosauridae) were more abundant in coastal and/or fluvial environments, while others (e.g. Marginocephalia, Ankylosauridae) preferentially inhabited more distal environments. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. An erratum to this article can be found at  相似文献   

5.
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   

6.
The Clean Development Mechanism (CDM) under the Kyoto Protocol to the UN Framework Convention on Climate Change (UNFCCC) has its origins in the decade of UNFCCC negotiations. ‘Joint implementation’ and ‘activities implemented jointly pilot’ opened the door for the project-based mechanisms between developed and developing countries. The US proposal of the Joint Implementation in the Kyoto Protocol negotiations was almost identical with CDM approved in Kyoto; however, a detour around the Clean Development Fund (CDF) concept raised by Brazil in the negotiations catalyzed the mutual understanding on the win-win nature of the concept of joint implementation.CDM has been played an important role to bridge the developed and developing countries in its development process initiated as the joint implementation in the UNFCCC, and can lead to the cooperative future in the implementation stage starting from the year 2003, including the development of future commitments beyond 2013. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

7.
Distinct acoustic whistles are associated with the wing-beats of many doves, and are especially noticeable when doves ascend from the ground when startled. I thus hypothesized that these sounds may be used by flock-mates as cues of potential danger. To test this hypothesis, I compared the responses of mourning doves (Zenaida macroura), northern cardinals (Cardinalis cardinalis), and house sparrows (Passer domesticus) to audio playbacks of dove ‘startle wing-whistles’, cardinal alarm calls, dove ‘nonstartle wing-whistles’, and sparrow ‘social chatter’. Following playbacks of startle wing-whistles and alarm calls, conspecifics and heterospecifics startled and increased vigilance more than after playbacks of other sounds. Also, the latency to return to feeding was greater following playbacks of startle wing-whistles and alarm calls than following playbacks of other sounds. These results suggest that both conspecifics and heterospecifics may attend to dove wing-whistles in decisions related to antipredator behaviors. Whether the sounds of dove wing-whistles are intentionally produced signals warrants further testing.  相似文献   

8.
Workers never mate in the large majority of ants, and they have usually lost the spermatheca, an organ specialized for long-term storage of sperm. Such ‘non-sexual’ workers are restricted to laying unfertilized eggs that give rise to males, and they cannot compete with the queens for the production of female offspring. In sharp contrast, workers in 200–300 species from phylogenetically basal subfamilies can reproduce sexually (‘gamergates’) because they retain a functional spermatheca like the queens. Importantly, ‘non-sexual’ workers in closely related species have a vestigial spermatheca. In this study, we compared the reservoir epithelium of ‘sexual’ workers to that of congeneric queens and ‘non-sexual’ workers using 21 species of Amblyoponinae, Ponerinae and Ectatomminae. We show that a pronounced thickening of the epithelium near the opening of the sperm duct is strictly associated with sexual reproduction in both castes. This is unlike ‘non-sexual’ workers in which this epithelium is always very thin, with few organelles; but all other structures remain intact. We discuss this evolutionary degeneration of the spermatheca and how it relates to behavioural or physiological modifications linked to mating. Our results help understand the loss of sexual reproduction by ant workers, a critical step in the extreme specialization of their phenotype.  相似文献   

9.
In ants, winged queens that are specialized for independent colony foundation can be replaced by wingless reproductives better adapted for colony fission. We studied this shift in reproductive strategy by comparing two Mystrium species from Madagascar using morphometry, allometry and dissections. Mystrium rogeri has a single dealate queen in each colony with a larger thorax than workers and similar mandibles that allow these queens to hunt during non-claustral foundation. In contrast, Mystrium ‘red’ lacks winged queens and half of the female adults belong to a wingless ‘intermorph’ caste smaller and allometrically distinct from the workers. Intermorphs have functional ovaries and spermatheca while those of workers are degenerate. Intermorphs care for brood and a few mate and reproduce making them an all-purpose caste that takes charge of both work and reproduction. However, their mandibles are reduced and inappropriate for hunting centipedes, unlike the workers’ mandibles. This together with their small thorax disallow them to perform independent colony foundation, and colonies reproduce by fission. M. rogeri workers have mandibles polymorphic in size and shape, which allow for all tasks from brood care to hunting. In M. ‘red’, colonial investment in reproduction has shifted from producing expensive winged queens to more numerous helpers. M. ‘red’ intermorphs are the first case of reproductives smaller than workers in ants and illustrate their potential to diversify their caste system for better colonial economy.  相似文献   

10.
Climate change associated global warming, rise in carbon dioxide concentration and uncertainties in precipitation has profound implications on Indian agriculture. Maize (Zea mays L.), the third most important cereal crop in India, has a major role to play in country’s food security. Thus, it is important to analyze the consequence of climate change on maize productivity in major maize producing regions in India and elucidate potential adaptive strategy to minimize the adverse effects. Calibrated and validated InfoCrop-MAIZE model was used for analyzing the impacts of increase in temperature, carbon dioxide (CO2) and change in rainfall apart from HadCM3 A2a scenario for 2020, 2050 and 2080. The main insights from the analysis are threefold. First, maize yields in monsoon are projected to be adversely affected due to rise in atmospheric temperature; but increased rainfall can partly offset those loses. During winter, maize grain yield is projected to reduced with increase in temperature in two of the regions (Mid Indo-Gangetic Plains or MIGP, and Southern Plateau or SP), but in the Upper Indo-Gangetic Plain (UIGP), where relatively low temperatures prevail during winter, yield increased up to a 2.7°C rise in temperature. Variation in rainfall may not have a major impact on winter yields, as the crop is already well irrigated. Secondly, the spatio-temporal variations in projected changes in temperature and rainfall are likely to lead to differential impacts in the different regions. In particular, monsoon yield is reduced most in SP (up to 35%), winter yield is reduced most in MIGP (up to 55%), while UIGP yields are relatively unaffected. Third, developing new cultivars with growth pattern in changed climate scenarios similar to that of current varieties in present conditions could be an advantageous adaptation strategy for minimizing the vulnerability of maize production in India.  相似文献   

11.
This study investigates the influence of policy interests on resource sustainability. Information on ‘colonial interest’ of the British regime and the ‘commercial interest’ of the post-colonial regimes on forest land use of Bangladesh have been drawn on to show the interplay of interests on sustainability impacts. The findings show that both colonial and commercial interests have caused intensification of forest land use for production of economic crops like teak (Tectona grandis) and cash crops like tea (Camellia sinensis), cotton (Gossypium herbaceum and G. arboreum) and tobacco (Nicotiana tabacum). The ‘colonial interest’ has also initiated the dispute of ownership, rights and tenure of forest land and resources. The post-colonial regimes have utilized colonial legacy as the privilege for implementing ‘commercial interests’. In both the cases traditional interests of people were disregarded. As a result, peoples’ participation in forestry was discouraged and the sustainability of forest land use was impeded.  相似文献   

12.
中国粮食安全系统脆弱性评价及其驱动机制分析   总被引:4,自引:0,他引:4  
从粮食安全系统的视角出发,运用VSD的脆弱性分析框架,从暴露性、敏感性、适应能力三个层面构建了中国粮食安全脆弱性评价指标体系,采用主成分分析方法对1991-2015年中国粮食安全脆弱性的暴露性、敏感性、适应能力进行定量分析,并探究了中国粮食安全脆弱性变化的总体趋势及其驱动因子。研究结果表明:(1)暴露性指数呈现出2阶段下降特征,年均下降0.121;敏感性指数呈现出快速上升和基本稳定的两阶段变化特征;适应能力指数则一直上升,年均提高0.117。(2)1991-2015年粮食安全系统脆弱性指数整体呈现下降趋势,表明中国粮食安水平有了明显提高;其变化过程可划分为1991-1999年、2000-2003年和2004-2015年三个阶段,第一、二阶段粮食安全水平的总体提高是基于“吃饱”水平上的提高,而第三阶段是基于“吃好”水平上的提高。(3)人均GDP、城镇化水平和城乡居民人均可支配收入四个因子共同驱动中国粮食安全脆弱性的变化,2000-2015年的第二阶段四因子对粮食安全脆弱性的驱动作用明显小于1991-1999的第一阶段,且第一驱动因子由第一阶段的农村居民人均可支配收入转变为第二阶段的人均GDP和城镇居民可支配收入。  相似文献   

13.
山东沿海七市耕地面积占全省耕地面积的37.91%,农业产值占全省的41.12%。由于经常受风暴潮的影响,农业损失巨大。沿海耕地分布区地势较为低平,潮水灌入农田,使当季农作物损失率为100%,同时又改变土壤性质,影响下一季农作物的生长,而防潮堤标准低且达标率不高,对百年一遇风暴潮抵抗力较弱。因此,对山东沿海地区耕地脆弱性评价有利于防灾减灾。本文利用landsat ETM、数字高程模型和地表覆盖数据,运用GIS系统评价山东沿海地区百年一遇潮位淹没影响的耕地脆弱性。将脆弱程度划分为七级,研究结果如下:极高脆弱性的地区是垦利县、东营区;很高脆弱性的地区有河口区、昌邑县、广饶县与寒亭区;高脆弱性的地区是城阳区、崂山区与寿光市;中脆弱区的地区有莱州市、平度市、垦利县与东营区;低脆弱的地区有岚山区、牟平市、文登市、荣成市、即墨市、胶州市、无棣县、东港区、龙口市、海阳市、河口区、沾化县与黄岛区;很低脆弱的地区有蓬莱市、环翠区、利津、芝罘区、崂山区、乳山市与城阳区;极低脆弱的地区有福山区、莱山区与招远市。其中垦利县、东营区、寒亭区、广饶县、昌邑县与寿光市的脆弱性是由于百年一遇潮位较高,淹没耕地比值大;河口区脆弱性是由于当地淹没耕地比值大。  相似文献   

14.
Bamboo in climate change and rural livelihoods   总被引:1,自引:0,他引:1  
Climate change negotiations, assessments, and greenhouse gas inventory guidelines have all but bypassed bamboo. Disallowing stands of tree-like bamboos as forests disparages their function in the carbon (C) cycle, and disregards pillars of smallholder livelihoods. Exposing bamboo not as a panacea, but as an overlooked option for C conservation, sequestration, and adaptation, we screen details of distribution, morphology, growth, physiology, and impacts for pertinence to climate change. Additional to 40 million hectares of existing bamboo forests, many potential host countries for C projects harbor suitable sites. Definitions, methods and default values, such as the root/shoot- ratio, biomass conversion factors, allometric equations and sampling variables need adjusting. Rapid maturation, persistent rhizomes, a rich palette of species, and wind-firmness may mitigate risk. Bamboos can accommodate agro-and urban forestry, and reign in unsustainable shifting cultivation. Distribution functions of bamboo biomass stocks and growths do not deviate drastically from those of trees. If anything, bamboo stocks are slightly lower, and growths slightly higher, with medians of 87 t*ha−1 and 10.5 t*ha−1*yr−1, respectively. However, bamboo’s outstanding socio-economic effects might well determine its future in mitigation and adaptation. Early, continuous yields, selective harvesting on even small parcels of land, low capital and high labor intensity, virtually 100% conversion efficiency to about 1,500 products, and, typically, 75% of economic returns benefiting rural people are advantageous attributes. Regional studies on suitability, silviculture, yields, economics, risk, and C assessment would strengthen bamboo’s function as ‘the poor man’s timber’ and promote its niche as the smallholder’s C sink.  相似文献   

15.
Carbon dioxide emissions from 1990 to 2100 AD are decomposed into the product of four factors: population size, affluence (measured here as GDP per capita), energy intensity (energy use per unit GDP) and carbon intensity (carbon dioxide emissions per unit energy). These emissions factors are further subdivided into three regions: more developed countries (MDCs), China, and the remaining less developed countries (LDCs). Departures from a baseline scenario (based on IPCC, 1992a — the so-called ‘business-as-usual’ scenario) are calculated for a variety of alternative assumptions concerning the four emissions factors in the three regions. Although the IPCC scenario is called a ‘non-intervention’ scenario, it is shown, for example, that large decreases in energy intensity in China or carbon intensity in MDCs are built into the ‘business as usual’ case — and such large changes vary considerably from region to region. We show what CO2 emissions would look like if each of these four emissions factors projected in the baseline case somehow remained constant at 1990 levels. Certain factors like energy intensity improvements and long-term population growth in LDCs, or GDP growth and carbon intensity improvements in MDCs, are shown to have a big contribution to cumulative global emissions to 2100 AD, and consequently, changes in these projected factors will lead to significant deviations from baseline emissions. None of the scenarios examined in this analysis seems to indicate that any one global factor is clearly dominant, but cultural, economic, and political costs or opportunities of altering each factor may differ greatly from country to country.  相似文献   

16.
Physiological clocks have been selected in various eukaryotic organisms in relation to daily, tidal, lunar and annual cycles of the environment. Insect species are appropriate experimental objects for the analysis of biological timing mechanisms and their evolutionary adaptation to the local environment. The most complex periodic environment occurs in the interface between the land and the sea, i.e., in the range of spring and neap tides. By the combination of ’circadian‘ and ’circalunar‘ clocks and their reliably perceptible ’zeitgeber‘ conditions, a few marine insects can temporally program their development to distinct tidal situations that occur only on distinct lunar days and at a distinct time of day every 14–15 days.  相似文献   

17.
This paper examines Sweden’s role as a pioneer in mitigating climate change. Critical discourse analysis of climate and energy policy unveils Sweden’s ambition to ‘lead-by-example’, by virtue of a win–win combination of economy and environment via stringent regulations and an early-mover strategy on eco-innovations. The extent of the unilateral approach is constrained by concerns for the competitiveness of energy-intensive industries and a persistent debate on the fate of Swedish nuclear power. Whilst Sweden has made significant demonstrative progress in reducing emissions and introducing renewable energy sources, these issues may limit her role as a pioneer in years to come.  相似文献   

18.
关注耕地转出行为对农户贫困脆弱性的影响,对于农民家庭的持久脱贫及农村反贫困政策的制定意义重大。基于CFPS两期全国整合样本的面板数据,在对农户贫困脆弱性进行测算的基础上,运用倍差法、OLS模型及倾向得分匹配倍差法,实证检验耕地转出对农民家庭贫困脆弱性的影响及其区域差异。结果表明:(1)耕地转出行为的发生降低了农户的贫困脆弱性,是一种有效的扶贫手段,在帮助部分农户抵御收入风险上起到了积极作用;(2)耕地转出规模的扩大并未显著改善农户的贫困脆弱性状况;(3)控制变量也对农户贫困脆弱性产生了不同程度的影响,其中户主性别、户主年龄和家庭住房净资产显著正向影响农户的贫困脆弱性水平,而户主受教育程度、家庭劳动力数、健康状况、现金和存款数及当地经济发展水平等变量显著负向影响农户的贫困脆弱性水平;(4)耕地转出行为对农民家庭贫困脆弱性的影响呈现出一定的区域差异性,对东、中和东北地区农户贫困脆弱性的降低起到了显著促进作用,但对西部地区农户的减贫作用并不明显。  相似文献   

19.
Among the key issues of concern to the Climate Convention is the stabilization of greenhouse gas concentrations and the minimization of impacts to global agriculture, natural ecosystems and economic development. The purpose of this paper is to couple these issues in consistent, integrated scenarios, using the IMAGE 2.0 model as an integrating tool. Scenarios of gradual stabilization of atmospheric CO2 at 350 and 450 ppm are compared to a baseline of no policy action in which CO2 concentration increases to 777 ppm. Under the stabilizaton scenarios substantially smaller areas of wheat and millet, as well as nature reserves, are threatened by climate change, especially in temperate regions. The amount of sea level rise is also reduced under the stabilization scenarios. However, climate continues to change under the stabilization scenarios and therefore some ‘residual’ climate impacts occur. Hence the integrated scenarios indicate that stabilizing greenhouse gas concentrations at or slightly above current levels will lessen impacts as compared to baseline levels, but not eliminate them. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

20.
Due to large scale afforestation programs and forest conservation legislations, India’s total forest area seems to have stabilized or even increased. In spite of such efforts, forest fragmentation and degradation continues, with forests being subject to increased pressure due to anthropogenic factors. Such fragmentation and degradation is leading to the forest cover to change from very dense to moderately dense and open forest and 253 km2 of very dense forest has been converted to moderately dense forest, open forest, scrub and non-forest (during 2005–2007). Similarly, there has been a degradation of 4,120 km2 of moderately dense forest to open forest, scrub and non-forest resulting in a net loss of 936 km2 of moderately dense forest. Additionally, 4,335 km2 of open forest have degraded to scrub and non-forest. Coupled with pressure due to anthropogenic factors, climate change is likely to be an added stress on forests. Forest sector programs and policies are major factors that determine the status of forests and potentially resilience to projected impacts of climate change. An attempt is made to review the forest policies and programs and their implications for the status of forests and for vulnerability of forests to projected climate change. The study concludes that forest conservation and development policies and programs need to be oriented to incorporate climate change impacts, vulnerability and adaptation.  相似文献   

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