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1.
Climate Vulnerability Index (CVI) is being proposed to assess climate change vulnerability of communities with a case study. The index consists of household parameters of all the three dimensions of vulnerability such as Exposure, Sensitivity and Adaptive Capability. Exposure is defined by ‘Natural disaster and Climate variability’, however Sensitivity by ‘Health’, Food’, and ‘Water’ and Adaptive Capability by ‘Socio-demographic profile’, ‘Livelihood strategies’, and ‘Social networks’. Respective parameters were based on the peers and literature. The CVI vulnerable status ranges from high (0) to low (1). Household questionnaire survey was undertaken from two regions namely, near to district (NDH) and away to district (ADH), in Srinagar, Uttrakhand, India. Data for desired parameters for CVI was collected from 50 randomly selected households. Data were aggregated using a composite index and differential vulnerabilities were compared. High vulnerability was observed for livelihood strategies, food and natural disaster for ADH households, and health and water for NDH households. It was found that the adaptive capability and sensitivity of ADH households was higher than NDH, however, exposure realization was similar in both the regions. The CVI was 0.69 and 0.64 for NDH and ADH, respectively, suggests high vulnerability to NDH households. This pragmatic CVI approach may be used to assess and monitor vulnerability under various stress condition, and/or evaluate potential program/ policy effectiveness in various data-scarce regions by comparing various anticipated scenarios with baseline. Further, the result obtained by index may have implications for developing adaptation or coping strategies to the region.  相似文献   

2.
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   

3.
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   

4.
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   

5.
It is now widely accepted that climate change is happening and that future changes will impact on many aspects of society, including agriculture. To maintain food supplies, the agricultural industry must address climate change adaptation. Key to this is the attitudes of those within the industry likely to have responsibility for adapting. This study investigated stakeholder attitudes towards adaptation to climate change in the livestock industry. Findings reveal four attitudinal groups. First, there is a ‘farmer-focused group’ that has a positive attitude about the ability of livestock farmers to adapt to climate change, but that also has the opinion that they will need additional support to adapt. Second, there is an ‘incentive for enterprise, anti-GM (genetic modification) group’ with an attitudinal position stressing that the government should have a role in implementing regulations and providing finance. This group has a negative attitude towards GM technology and does not think it will be the answer to climate change. Third, there is an ‘information and education group’ whose attitude is that the provision of information is crucial for ensuring that the livestock industry adapts. Fourth, there is a ‘pro-technology group’ who have a positive attitude towards GM technology and who are therefore willing to embrace it as the route to adaptation. Three of these four groups favour soft adaptations that maintain flexibility within the system, and only the fourth is of the opinion that adaptive capacity is not an issue and that the industry is ready to implement hard adaptations.  相似文献   

6.
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   

7.
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   

8.
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   

9.
Fires have attracted interest and generated alarm since the early 1980s. This concern has been particularly evident in tropical forests of Southeast Asia and the Amazon, but disastrous fires in recent summers in Australia, Europe, and the United States have drawn worldwide attention. Concern about forest fires, and related air pollution and biodiversity impacts, led international organisations and northern countries – such as the Asian Development Bank, the European Union, the Food and Agriculture Organisation, the United Nations Environment Programme, the World Bank, and the government of Germany – to undertake fire assessments and provide technical assistance. Nongovernmental organisations, such as the International Union for Conservation of Nature and Natural Resources and World Wide Fund for Nature, have also devoted increased attention to fires. Aiming at prevention of future fires, 40 fire projects and missions costing well over US$30 million have worked in Indonesia over the last 20 years. Despite the money and effort spent on them, fires continue to burn every year. It may appear to some that efforts to address the ‘fire problem’ have not been effective as fires still occur. There remains a lack of clarity about ‘fire problems’, which has, at times, led to the adoption of policies that may have negative impacts on livelihoods, the environment, and the economy. Two ‘simple’ changes in the way fires are considered would significantly improve fire-related policies and initiatives.
•  Fires should be seen as a component of land management processes, rather than as a ‘problem’ to be prevented, suppressed, or mitigated.
•  Not all fires are the same.
These two points are discussed in the context of Southeast Asia, and particularly Indonesia, as an example of the problems and questions faced by tropical countries. We argue that efforts on fires so far have generated increased knowledge of the ’fire problem’; now, we need to capitalize on that knowledge to avoid wasting money in the future.  相似文献   

10.
Giant honeybees (Apis dorsata) nest in the open and have therefore evolved a variety of defence strategies. Against predatory wasps, they produce highly coordinated Mexican wavelike cascades termed ‘shimmering’, whereby hundreds of bees flip their abdomens upwards. Although it is well known that shimmering commences at distinct spots on the nest surface, it is still unclear how shimmering is generated. In this study, colonies were exposed to living tethered wasps that were moved in front of the experimental nest. Temporal and spatial patterns of shimmering were investigated in and after the presence of the wasp. The numbers and locations of bees that participated in the shimmering were assessed, and those bees that triggered the waves were identified. The findings reveal that the position of identified trigger cohorts did not reflect the experimental path of the tethered wasp. Instead, the trigger centres were primarily arranged in the close periphery of the mouth zone of the nest, around those parts where the main locomotory activity occurs. This favours the ‘special-agents’ hypothesis that suggest that groups of specialized bees initiate the shimmering.  相似文献   

11.
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   

12.
Joint Implementation is a theoretically efficient instrument of climate policy at least in the short run. This need not apply for the long run. Joint Implementation can reduce innovation in the industrialized countries because of reduced incentives for emission reduction. To realize short run efficiency gains and to avoid long run efficiency losses, we need a ‘strategic’ climate policy. This policy should start with full crediting of Joint Implementation allowing short-run efficiency gains which can foster technology transfer and thus lead to ‘leapfrogging’ by developing countries. Over time, the crediting ratio should be gradually reduced while domestic carbon taxes are raised. Experiences from the second oil shock have shown that energy-saving innovation is positively correlated to energy prices. Both, the reduced crediting and the raising domestic carbon tax, will therefore lead to long-run innovation.  相似文献   

13.
The Dead Sea of Israel, Jordan and Syria is a severely disturbed ecosystem, greatly damaged by anthropogenic intervention in its water balance. During the 20 th century, the Dead Sea level dropped by more than 25 meters, and presently (2003) it is at about 416 meters below mean sea level. This negative water balance is mainly due to the diversion of water from the catchment area of the lake by Israel, Jordan and Syria. During the 2002 World Summit on Sustainable Development Israel and Jordan jointly announced their interest in saving the Dead Sea by constructing the ‘Peace Conduit’ that will pipe water from the Red Sea to the Dead Sea. The inflow of seawater (or reject brine after desalinization) into the Dead Sea will have a major impact on its limnology, geochemistry and biology. During the filling stage, relatively diluted surface water will form and the rate of evaporation will therefore increase. Dilution of the surface water will most likely result in microbial blooming whose duration is not known, while the lower water layer is likely to develop reducing conditions, including bacterial sulfate reduction and presence of hydrogen sulfide (H2S). Mixing between the calcium-rich Dead Sea brine and the sulfate-rich seawater will result in gypsum precipitation (CaSO4·2H2O). Once the target level is reached, inflow will be outbalanced by evaporation and salinity of the surface water will increase due to accumulation of sea water-salts. The water column will remix when the density of the surface water will equal that of the lower water column. In spite of its large volume and high salinity relative to that of the inflowing water, over the long run the composition of this unique lake will change. Before a decision is made on the planning and construction of the Conduit, it is essential that the long term evolution and characteristics of the ‘renewed’ Dead Sea be known and anticipated changes examined. Once decided upon, the planning and construction of the Conduit should be conducted so as to minimize possible negative impacts of seawater introduction on the Dead Sea. This can only be achieved through a thorough understanding of the expected changes in the limnological physical/chemical characteristics of the Dead Sea and its unique brine.  相似文献   

14.
We proposed the carbon sink project called “Carbon Sequestration by Forestation and Carbonization (CFC),” which involves biomass utilization and land conservation by incorporating the products of biomass carbonization into the agents for soil improvement, water purification, etc. Our purpose was to demonstrate the potential of the CFC scheme for carbon sequestration, particularly carbon storage in soil. Case studies were conducted in both developing and developed countries. 1. In southern Sumatra, Indonesia, 88,369 Mg-C year−1 of wood residue from a plantation forest and excess bark from a pulp mill would be converted into 15,571 Mg-C year−1 of the net carbon sink by biochar for soil improvement. The fixed carbon recovery of the system is 21.0%. 2. In a semiarid region in western Australia, the carbonization of wood residue was incorporated with multipurpose projects of a mallee eucalyptus plantation that involved the function of salinity prevention. During the project period of 35 years, the total carbon sink would reach 1,035,450 Mg-C with 14.0% by aboveground biomass, 33.1% by belowground biomass and 52.8% by biochar in soil. 3. In southern Kyushu, Japan, the study was focused on the effective use of surplus heat from a garbage incinerator for carbonizing woody materials. Sawdust of 936.0 Mg-C year−1 would be converted into the net carbon sink of 298.5 Mg-C year−1 by carbonization, with the fixed carbon recovery of the system being 31.9%. Consequently, the CFC project could encourage the creation of a carbon sink in soil. However, we recognize that the quality standard of biochar, the stability of biochar in soil, and the methods for monitoring biochar utilization must be clarified before incorporating biochar carbon into the carbon credit system. Throughout this article (except for diagrams and in citation details) carbonized biomass is, with the authors'agreement, called ‘biochar’ in lieu of the commonly used but misleading word ‘charcoal’ (Editor).  相似文献   

15.
为揭示我国北方温带水库——周村水库水体季节性分层现象及其水质响应特性,于2014年7月~2015年6月对周村水库进行了37次采样,并对水体理化指标和浮游植物进行了原位监测.结果表明,周村水库在4~11月间处于水体分层,全年呈典型的温带单循环混合模式.水温分层对水库水环境的变化起着重要的作用,热分层引起的底层水体季节性缺氧,导致了沉积物中营养盐以及还原性物质的大量释放,其中热分层期底层水体总氮、总磷、锰和硫化物的平均值分别为1.18、0.11、0.47和0.48 mg·L~(-1);浮游植物垂向分布受水温分层的显著影响,热分层期上层水体浮游植物丰度较高,其均值为16.35×106cells·L~(-1),下层水体浮游植物丰度维持在较低水平.  相似文献   

16.
The use of species distribution models (SDMs) to predict potential distributions of species is steadily increasing. A necessary assumption when projecting models throughout space or time is that climatic niches are conservative, but recent findings of niche shifts during biological invasion of particular plant and animal species have indicated that this assumption is not categorically valid. One reason for observed shifts may relate to variable selection for modelling. In this study, we assess differences in climatic niches in the native and invasive ranges of the Greenhouse frog (Eleutherodactylus planirostris). We analyze which variables are more ‘conserved’ in comparison to more ‘relaxed’ variables (i.e. subject to niche shift) and how they influence transferability of SDMs developed with Maxent on the basis of ten bioclimatic layers best describing the climatic requirements of the target species. We focus on degrees of niche similarity and conservatism using Schoener's index and Hellinger distance. Significance of results are tested with null models. Results indicate that the degrees of niche similarity and conservatism vary greatly among the predictive variables. Some shifts can be attributed to active habitat selection, whereas others apparently reflect variation in the availability of climate conditions or biotic interactions between the frogs' native and invasive ranges. Patterns suggesting active habitat selection also vary among variables. Our findings evoke considerable implications on the transferability of SDMs over space and time, which is strongly affected by the choice and number of predictors. The incorporation of ‘relaxed’ predictors not or only indirectly correlated with biologically meaningful predictors may lead to erroneous predictions when projecting SDMs. We recommend thorough assessments of invasive species' ecology for the identification biologically meaningful predictors facilitating transferability.  相似文献   

17.
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   

18.
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   

19.
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   

20.
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