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1.
The pivotal question in the debate on the ecological effects of climate change is whether species will be able to adapt fast enough to keep up with their changing environment. If we establish the maximal rate of adaptation, this will set an upper limit to the rate at which temperatures can increase without loss of biodiversity.The rate of adaptation will primarily be set by the rate of microevolution since (i) phenotypic plasticity alone is not sufficient as reaction norms will no longer be adaptive and hence microevolution on the reaction norm is needed, (ii) learning will be favourable to the individual but cannot be passed on to the next generations, (iii) maternal effects may play a role but, as with other forms of phenotypic plasticity, the response of offspring to the maternal cues will no longer be adaptive in a changing environment, and (iv) adaptation via immigration of individuals with genotypes adapted to warmer environments also involves microevolution as these genotypes are better adapted in terms of temperature, but not in terms of, for instance, photoperiod.Long-term studies on wild populations with individually known animals play an essential role in detecting and understanding the temporal trends in life-history traits, and to estimate the heritability of, and selection pressures on, life-history traits. However, additional measurements on other trophic levels and on the mechanisms underlying phenotypic plasticity are needed to predict the rate of microevolution, especially under changing conditions.Using this knowledge on heritability of, and selection on, life-history traits, in combination with climate scenarios, we will be able to predict the rate of adaptation for different climate scenarios. The final step is to use ecoevolutionary dynamical models to make the link to population viability and from there to biodiversity loss for those scenarios where the rate of adaptation is insufficient.  相似文献   

2.
Aeroterrestrial phototrophic biofilms colonize natural and man-made surfaces and may damage the material they settle on. The occurrence of biofilms varies between regions with different climatic conditions. The aim of this study was to evaluate the influence of meteorological factors on the growth of aeroterrestrial phototrophs. Phototrophic biomass was recorded on roof tiles at six sites within Germany five times over a period of five years and compared to climatic parameters from neighboring weather stations. All correlating meteorological factors influenced water availability on the surface of the roof tiles. The results indicate that the frequency of rainy days and not the mean precipitation per season is more important for biofilm proliferation. It is also inferred that the macroclimate is more important than the microclimate. In conclusion, changed (regional) climatic conditions may determine where in central Europe global change will promote or inhibit phototrophic growth in the future.  相似文献   

3.
Climate, physical landscapes, and biota interact to generate heterogeneous hydrologic conditions in space and over time, which are reflected in spatial patterns of species distributions. As these species distributions respond to rapid climate change, microrefugia may support local species persistence in the face of deteriorating climatic suitability. Recent focus on temperature as a determinant of microrefugia insufficiently accounts for the importance of hydrologic processes and changing water availability with changing climate. Where water scarcity is a major limitation now or under future climates, hydrologic microrefugia are likely to prove essential for species persistence, particularly for sessile species and plants. Zones of high relative water availability – mesic microenvironments – are generated by a wide array of hydrologic processes, and may be loosely coupled to climatic processes and therefore buffered from climate change. Here, we review the mechanisms that generate mesic microenvironments and their likely robustness in the face of climate change. We argue that mesic microenvironments will act as species‐specific refugia only if the nature and space/time variability in water availability are compatible with the ecological requirements of a target species. We illustrate this argument with case studies drawn from California oak woodland ecosystems. We posit that identification of hydrologic refugia could form a cornerstone of climate‐cognizant conservation strategies, but that this would require improved understanding of climate change effects on key hydrologic processes, including frequently cryptic processes such as groundwater flow.  相似文献   

4.
在气候变化背景下,深入揭示玉米气候生产力的变化趋势及其空间差异、明晰玉米气候资源利用规律,可为黑龙江省农业生产宏观决策提供科学依据.基于黑龙江省72个气象站1981—2014年的气象资料和对应的产量资料,采用逐步订正、空间插值、线性趋势分析等方法,研究玉米的光合、光温、气候生产力的时空变化特征、主要影响因素和增产潜力,并对未来不同气候情景下玉米气候生产力进行评估.结果表明: 研究期间,黑龙江省玉米光合、光温和气候生产力平均值分别为26558、19953和18742 kg·hm-2;在空间分布上均表现为平原高山地低、由西南向东北逐渐减少;光合、光温、气候生产力均表现为显著增加趋势,其增幅分别为378、723和560 kg·hm-2·(10 a)-1,且辐射量和气温的增加对黑龙江省玉米生产具有正效应;玉米气候生产力对气候变化响应明显,松嫩平原西部因光能资源的减少导致玉米光合生产力降低,气温升高则在一定程度上弥补了光照带来的负面效应,玉米光温生产力下降趋势有所减缓,北部和东部对气候变暖的响应表现尤为明显,玉米光温生产力表现为明显上升趋势,而松嫩平原西南部及三江平原易旱区则对降水变化反映敏感;玉米实际单产与其气候生产力比率的平均值仅为24.1%,仍有75.9%的潜力有待开发;未来“暖湿型”气候对提高玉米气候生产力有利,而“冷干型”气候则不利于玉米气候生产力的提高.  相似文献   

5.
Invertebrates,ecosystem services and climate change   总被引:1,自引:0,他引:1  
The sustainability of ecosystem services depends on a firm understanding of both how organisms provide these services to humans and how these organisms will be altered with a changing climate. Unquestionably a dominant feature of most ecosystems, invertebrates affect many ecosystem services and are also highly responsive to climate change. However, there is still a basic lack of understanding of the direct and indirect paths by which invertebrates influence ecosystem services, as well as how climate change will affect those ecosystem services by altering invertebrate populations. This indicates a lack of communication and collaboration among scientists researching ecosystem services and climate change effects on invertebrates, and land managers and researchers from other disciplines, which becomes obvious when systematically reviewing the literature relevant to invertebrates, ecosystem services, and climate change. To address this issue, we review how invertebrates respond to climate change. We then review how invertebrates both positively and negatively influence ecosystem services. Lastly, we provide some critical future directions for research needs, and suggest ways in which managers, scientists and other researchers may collaborate to tackle the complex issue of sustaining invertebrate‐mediated services under a changing climate.  相似文献   

6.
Industrial ecology (IE) has made great contributions to climate change mitigation research, in terms of its systems thinking and solid methodologies such as life cycle assessment, material flow analysis, and environmentally extended input–output analysis. However, its potential contribution to climate change adaptation is unclear. Adaptation has become increasingly urgent in a continuously changing climate, especially in developing countries, which are projected to bear the brunt of climate‐change‐related damages. On the basis of a brief review of climate change impacts and adaptation literature, we suggest that IE can play an important role in the following two aspects. First, with the emphasis on a systems perspective, IE can help us determine how climate change interacts with our socio‐economic system and how the interactions may aggravate (or moderate) its direct impacts or whether they may shift burden to other environmental impacts. Second, IE methodologies can help us quantify the direct and indirect environmental impacts of adaptation activities, identify mitigation opportunities, and achieve sustainable adaptation. Further, we find that substantial investment is needed to increase the resilience of infrastructure (e.g., transport, energy, and water supply) and agriculture in developing countries. Because these sectors are also the main drivers of environmental degradation, how to achieve sustainable climate‐resilient infrastructure and agriculture in developing countries deserves special attention in future IE studies. Overall, IE thinking and methodologies have great potential to contribute to climate change adaptation research and policy questions, and exploring this growing field will, in turn, inspire IE development.  相似文献   

7.
F. P. O'Mara 《Annals of botany》2012,110(6):1263-1270

Background

Grasslands are a major part of the global ecosystem, covering 37 % of the earth''s terrestrial area. For a variety of reasons, mostly related to overgrazing and the resulting problems of soil erosion and weed encroachment, many of the world''s natural grasslands are in poor condition and showing signs of degradation. This review examines their contribution to global food supply and to combating climate change.

Scope

Grasslands make a significant contribution to food security through providing part of the feed requirements of ruminants used for meat and milk production. Globally, this is more important in food energy terms than pig meat and poultry meat. Grasslands are considered to have the potential to play a key role in greenhouse gas mitigation, particularly in terms of global carbon storage and further carbon sequestration. It is estimated that grazing land management and pasture improvement (e.g. through managing grazing intensity, improved productivity, etc) have a global technical mitigation potential of almost 1·5 Gt CO2 equivalent in 2030, with additional mitigation possible from restoration of degraded lands. Milk and meat production from grassland systems in temperate regions has similar emissions of carbon dioxide per kilogram of product as mixed farming systems in temperate regions, and, if carbon sinks in grasslands are taken into account, grassland-based production systems can be as efficient as high-input systems from a greenhouse gas perspective.

Conclusions

Grasslands are important for global food supply, contributing to ruminant milk and meat production. Extra food will need to come from the world''s existing agricultural land base (including grasslands) as the total area of agricultural land has remained static since 1991. Ruminants are efficient converters of grass into humanly edible energy and protein and grassland-based food production can produce food with a comparable carbon footprint as mixed systems. Grasslands are a very important store of carbon, and they are continuing to sequester carbon with considerable potential to increase this further. Grassland adaptation to climate change will be variable, with possible increases or decreases in productivity and increases or decreases in soil carbon stores.  相似文献   

8.
To investigate the relationships between tick-borne encephalitis (TBE) virus and the bacterial spirochaete Borrelia burgdorferi sensu lato in vectors with mixed infections, unfed adult Ixodes persulcatus ticks were collected by flagging from vegetation in southern-taiga forests of the Pre-Urals region of Russia where both infections circulate sympatrically. Prevalences of TBE and Borrelia infections in a total of 4234 ticks were compared over 5 years. No significant differences were revealed between the prevalence of Borrelia infection in ticks with and without TBE virus (29.4+/-7.8% vs 23+/-3.6%), or between the prevalence of TBE virus infection in ticks with and without Borrelia (24.0+/-6.6% vs 18.4+/-3.4%). In ticks with mixed infection (40/689 = 5.8%), concentrations of TBE virus and Borrelia were not significantly correlated with one another. Field observations showed parallel trends in the prevalence of these pathogens in tick populations from year to year (1993-1997) indicating that, in I. persulcatus with mixed infection, Borrelia and TBE virus do not seem to interfere with each other and are apparently not involved in any antagonistic relationships.  相似文献   

9.
Observed ecological responses to climate change are highly individualistic across species and locations, and understanding the drivers of this variability is essential for management and conservation efforts. While it is clear that differences in exposure, sensitivity, and adaptive capacity all contribute to heterogeneity in climate change vulnerability, predicting these features at macroecological scales remains a critical challenge. We explore multiple drivers of heterogeneous vulnerability across the distributions of 96 vegetation types of the ecologically diverse western US, using data on observed climate trends from 1948 to 2014 to highlight emerging patterns of change. We ask three novel questions about factors potentially shaping vulnerability across the region: (a) How does sensitivity to different climate variables vary geographically and across vegetation classes? (b) How do multivariate climate exposure patterns interact with these sensitivities to shape vulnerability patterns? (c) How different are these vulnerability patterns according to three widely implemented vulnerability paradigms—niche novelty (decline in modeled suitability), temporal novelty (standardized anomaly), and spatial novelty (inbound climate velocity)—each of which uses a distinct frame of reference to quantify climate departure? We propose that considering these three novelty paradigms in combination could help improve our understanding and prediction of heterogeneous climate change responses, and we discuss the distinct climate adaptation strategies connected with different combinations of high and low novelty across the three metrics. Our results reveal a diverse mosaic of climate change vulnerability signatures across the region's plant communities. Each of the above factors contributes strongly to this heterogeneity: climate variable sensitivity exhibits clear patterns across vegetation types, multivariate climate change data reveal highly diverse exposure signatures across locations, and the three novelty paradigms diverge widely in their climate change vulnerability predictions. Together, these results shed light on potential drivers of individualistic climate change responses and may help to inform effective management strategies.  相似文献   

10.
Interval between clutches, fitness, and climate change   总被引:2,自引:0,他引:2  
Timing of optimal reproduction can be affected by the presenceof multiple broods, with multi-brooded species breeding earlier(and later) than the optimal timing of breeding as comparedwith single-brooded species that only need to optimize the timingof a single brood. Approximately two-thirds of barn swallowsHirundo rustica produce 2 broods per year, and I tested whetherthe constraints on timing of reproduction were affected by climatechange because climatic amelioration would allow both an earlierstart and a later termination of reproduction. The durationof the interval between first and second clutches and the variancein the duration increased during 1971–2005 when temperatureduring spring, but not summer, increased rapidly. Interclutchinterval was shorter when mean date of breeding was late andalso among late-breeding individuals during individual years.When clutch size and brood size of the first clutch were large,interval until the second brood increased. Pairs with a longinterval produced more fledglings than pairs with a short interval.Pairs with first broods with strong mean T-cell–mediatedimmune responses took shorter time to start their second clutch,whereas mean body mass or tarsus length of first broods werenot significantly related to interclutch interval. Interclutchinterval increased with the size of a secondary sexual character,the length of the outermost tail feathers of adult male barnswallows, but not with tail length of females, or with sizeof several other phenotypic characters in either sex. Thesefindings are consistent with the hypothesis that the durationof the interclutch interval is determined by a combination ofenvironmental conditions, reproductive effort, and sexual selection.  相似文献   

11.
12.
Protandry, sexual selection and climate change   总被引:6,自引:0,他引:6  
Protandry refers to the earlier appearance of males before females at sites of reproduction. Sexual selection has been hypothesized to give rise to sex differences in benefits and costs of early arrival, thereby selecting for earlier appearance by the sex subject to more intense sexual selection. If sexual selection is more intense, there is a greater premium on early arrival among individuals of the chosen sex because of direct selection for earlier arrival. This hypothesis leads to the prediction that changes in the costs and benefits of early arrival related to changes in environmental conditions should particularly affect the sex that arrives first and hence the degree of protandry. I tested this hypothesis using the Barn Swallow Hirundo rustica. During 1971–2003, the degree of protandry increased significantly in a Danish population because males advanced arrival date while females did not. This earlier arrival by males compared with females was correlated with a significant increase by over 1.2 standard deviations in the length of the outermost tail feathers of males, a secondary sexual character, suggesting direct selection on both protandry and the secondary sexual character. Environmental conditions during spring migration in Northern Africa, as reflected by the normalized difference vegetation index, have deteriorated since 1984, resulting in increased mortality among males during spring migration, but not among females, and this deterioration of climatic conditions was positively correlated with an increasing degree of protandry. Likewise, an increase in April temperatures at the breeding grounds during recent decades is positively correlated with increased protandry, apparently because males can arrive earlier without increasing the fitness cost of early arrival. Local population size did not predict changes in arrival date. These findings suggest that rapid changes in climate can cause a change in degree of protandry and secondary sexual characters.  相似文献   

13.
Impact of expected climate change on mangroves   总被引:6,自引:0,他引:6  
C. D. Field 《Hydrobiologia》1995,295(1-3):75-81
There is a consensus of scientific opinion that the activities of man will cause a significant change in the global climate over the next hundred years. The rising level of carbon dioxide and other industrial gases in the atmosphere may lead to global warming with an accompanying rise in sea-level. Mangrove ecosystems grow in the intertidal zones in tropical and sub-tropical regions and are likely to be early indicators of the effects of climate change. The best estimates of predicted climate change in the literature are presented. It is suggested that a rise in mean sea-level may be the most important factor influencing the future distribution of mangroves but that the effect will vary dramatically depending on the local rate of sea-level rise and the availability of sediment to support reestablishment of the mangroves. The predicted rise in mean air temperature will probably be of little consequence to the development of mangroves in general but it may mean that the presence of mangroves will move further north and south, though this will depend on a number of additional factors. The effect of enhanced atmospheric CO2 on the growth of mangroves is unknown at this time but that there is some evidence that not all species of mangroves will respond similarly. The socio-economic impacts of the effects of climate on mangrove ecosystems may include increased risk of flooding, increased erosion of coast lines, saline intrusion and increased storm surges.  相似文献   

14.
气候变化对鸟类影响的研究进展   总被引:1,自引:0,他引:1  
气候变化对生物多样性的影响已成为热点问题.本文以鸟类为研究对象,根据鸟类受气候变化影响的最新研究成果,综述了气候变化对鸟类的分布、物候和种群等方面的影响.结果表明,在气候变化影响下,鸟类分布向高纬度或高海拔区移动,速度比以往加快,繁殖地和非繁殖地的分布移动变化并不相同,并且多数分布范围缩小,物候期发生复杂变化,种群数量下降明显.文章还讨论了该领域主要的预测和评估方法,以及进化适应等生物因素对气候变化预测结果的影响,除了以往单一的相关性模型外,目前应用最多的是集成模型,而未来最具发展潜力的是机理模型.进化适应方面的研究近来取得新进展,证实了生物个体积极应对气候变化影响的事实,从而对人为模型预测的准确性带来挑战.文章最后进行了总结和展望,结合国外研究经验和我国实际情况,提出一些建议:由于气候变化的影响及其研究是长期性的,从而对鸟类的历史监测数据提出很高的要求,当前我国急需建立一套长期、全面和可靠的鸟类数据监测系统;此外,人们需要综合评估现有各种预测模型的可靠性,在此基础上探索新的研究方法.  相似文献   

15.
人工绿洲对夏季气候变化趋势的影响   总被引:4,自引:0,他引:4  
杨青  雷加强  魏文寿  赵景峰 《生态学报》2004,24(12):2728-2734
在绿洲的气候环境效应方面 ,此前的研究主要是基于个别地点的短期 (几天或几个月 )观测资料进行对比 ,分析绿洲与荒漠之间的要素差异和能量交换机制。通过细致筛选那些观测环境变化小、人口密度低、没有进行大规模水土开发地区的气象站 ,建立了反映背景变化的气候序列 ,同时选择不同地区的气象站建立了绿洲气候序列 ,分析背景与绿洲在气温、降水、水汽压、蒸发、风速等 9个气候因子近 5 0 a来气候趋势变化率的差异 ,研究绿洲发展对长年代气候变化的综合影响。结果表明 ,绿洲发展产生的气候环境效应在影响局部地区长期气候变化趋势方面是十分明显的。在夏季 ,绿洲平均气温的增温变化趋势要小于背景变化趋势 ,有些绿洲地区如吐 -善 -托盆地和叶尔羌河流域绿洲气温变化趋势还略呈下降趋势。绿洲地区对最高气温的变化趋势有着明显的抑制作用。其中 ,叶尔羌河流域绿洲和塔里木河中游地区绿洲最高气温变化趋势略呈下降趋势。绿洲地区对最低气温上升的变化趋势有一定的加强影响 ,绿洲效应使日较差正在变的越来越小。夏季绿洲对空中水汽压的增加十分明显 ,使蒸发潜力变得越来越弱 ,对降水有一定程度的增加作用。绿洲效应最为显著的一个方面是风速的变化 ,绿洲使平均风速和大风日数大幅度减少  相似文献   

16.
Yuan HY  Zhang XY  Xu HJ  Yang XG 《应用生态学报》2011,22(5):1247-1254
基于1961-2009年宁夏21个气象站点的气象资料,分析了宁夏各区农业气候资源的时空变化趋势.结果表明:研究期间,宁夏各地气温逐渐升高,呈北高南低的空间分布特征,年均气温的气候倾向率为0.4℃·(10 a)-1;大部分地区年降水量呈逐渐减少趋势,年降水量的气候倾向率为4.26 mm·(10 a)-1;无霜期和作物生长季天数随着气候变暖逐渐延长;≥10℃积温在3200℃·d以上的区域向南扩展,宁夏适宜种植中晚熟水稻的区域有所扩大;2001-2009年,宁夏大部分地区适宜种植冬小麦,全区各地几乎都适宜种植春小麦;宁夏南部山区各地7月平均气温≤20℃的区域面积逐渐缩小,适宜种植马铃薯的地域也随之缩小.  相似文献   

17.
Phenology of British butterflies and climate change   总被引:14,自引:0,他引:14  
Data from a national butterfly monitoring scheme were analysed to test for relationships between temperature and three phenological measures, duration of flight period and timing of both first and peak appearance. First appearances of most British butterflies has advanced in the last two decades and is strongly related to earlier peak appearance and, for multibrooded species, longer flight period. Mean dates of first and peak appearance are examined in relation to Manley's central England temperatures, using regression techniques. We predict that, in the absence of confounding factors, such as interactions with other organisms and land‐use change, climate warming of the order of 1 °C could advance first and peak appearance of most butterflies by 2–10 days.  相似文献   

18.
The rapid increase of atmospheric CO2 resulting from anthropogenic activites has stimulated a great deal of interest in the carbon cycle. Important decisions need to be made about future tolerable levels of atmospheric CO2 content, as well as the land and fossil fuel use strategies that will permit us to achieve these goals. The vast amount of new data on atmospheric CO2 content and ancillary properties that has become available during the last decade, and the development of models to interpret these data, have led to significant advances in our capacity to deal with such issues. However, a major continuing source of uncertainty is the role of photosynthesis in providing a sink for anthropogenic emissions. It is thus appropriate that a new evaluation of the status of our understanding of this issue should be made at this time.The aim of this paper is to provide a setting for the papers that follow by giving an overview of the role of carbon dioxide in climate, the biogeochemical processes that control its distribution, and the evolution of carbon dioxide through time from the origin of the earth to the present. We begin with a discussion of relevant processes. We then proceed to a more detailed discussion of the time periods that are best documented: the late Pleistocene (during which time large continental ice sheets waxed and waned) and the modern era of anthropogenic impact on the carbon cycle.  相似文献   

19.
The velocity of climate change is an elegant analytical concept that can be used to evaluate the exposure of organisms to climate change. In essence, one divides the rate of climate change by the rate of spatial climate variability to obtain a speed at which species must migrate over the surface of the earth to maintain constant climate conditions. However, to apply the algorithm for conservation and management purposes, additional information is needed to improve realism at local scales. For example, destination information is needed to ensure that vectors describing speed and direction of required migration do not point toward a climatic cul‐de‐sac by pointing beyond mountain tops. Here, we present an analytical approach that conforms to standard velocity algorithms if climate equivalents are nearby. Otherwise, the algorithm extends the search for climate refugia, which can be expanded to search for multivariate climate matches. With source and destination information available, forward and backward velocities can be calculated allowing useful inferences about conservation of species (present‐to‐future velocities) and management of species populations (future‐to‐present velocities).  相似文献   

20.
为鉴定我国森林脑炎病毒亚型,了解基因组结构与生物功能的关系,同时为森林脑炎病毒新型疫苗研制打下基础,对森林脑炎病毒森张株编码区序列进行测定。根据已发表的Sofjin-HO、Oshima5-10株序列设计9对重叠引物,通过RT—PCR扩增不同的cDNA片段,分别克隆至pGEM—T载体,转化DH5α菌,挑阳性克隆PCR、酶切鉴定后测序。结果表明森张株编码区全长10245nt,编码3414个氨基酸。我国森林脑炎病毒森张株与Oshima5—10、Sofiin—HO、Sofiin同源性最近,属于远东亚型。  相似文献   

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