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1.
    
The equations used to account for the temperature dependence of biological processes, including growth and metabolic rates, are the foundations of our predictions of how global biogeochemistry and biogeography change in response to global climate change. We review and test the use of 12 equations used to model the temperature dependence of biological processes across the full range of their temperature response, including supra‐ and suboptimal temperatures. We focus on fitting these equations to thermal response curves for phytoplankton growth but also tested the equations on a variety of traits across a wide diversity of organisms. We found that many of the surveyed equations have comparable abilities to fit data and equally high requirements for data quality (number of test temperatures and range of response captured) but lead to different estimates of cardinal temperatures and of the biological rates at these temperatures. When these rate estimates are used for biogeographic predictions, differences between the estimates of even the best‐fitting models can exceed the global biological change predicted for a decade of global warming. As a result, studies of the biological response to global changes in temperature must make careful consideration of model selection and of the quality of the data used for parametrizing these models.  相似文献   

2.
  总被引:5,自引:0,他引:5  
Climate change treatments – winter warming, summer drought and increased summer precipitation – have been imposed on an upland grassland continuously for 7 years. The vegetation was surveyed yearly. In the seventh year, soil samples were collected on four occasions through the growing season in order to assess mycorrhizal fungal abundance. Mycorrhizal fungal colonisation of roots and extraradical mycorrhizal hyphal (EMH) density in the soil were both affected by the climatic manipulations, especially by summer drought. Both winter warming and summer drought increased the proportion of root length colonised (RLC) and decreased the density of external mycorrhizal hyphal. Much of the response of mycorrhizal fungi to climate change could be attributed to climate‐induced changes in the vegetation, especially plant species relative abundance. However, it is possible that some of the mycorrhizal response to the climatic manipulations was direct – for example, the response of the EMH density to the drought treatment. Future work should address the likely change in mycorrhizal functioning under warmer and drier conditions.  相似文献   

3.
1. We explored differential population responses to climate in 18 populations of threatened spring-summer Chinook salmon Onchorynchus tshawytscha in the Salmon River basin, Idaho. 2. Using data from a long-term mark-release-recapture study of juvenile survival, we found that fall stream flow is the best predictor of average survival across all populations. 3. To determine whether all populations responded similarly to climate, we used a cluster analysis to group populations that had similar annual fluctuations in survival. The populations grouped into four clusters, and different environmental factors were important for different clusters. 4. Survival in two of the clusters was negatively correlated with summer temperature, and survival in the other two clusters was positively correlated with minimum fall stream flow, which in turn depends on snow pack from the previous winter. 5. Using classification and regression tree analysis, we identified stream width and stream temperature as key habitat factors that shape the responses of individual populations to climate. 6. Climate change will likely have different impacts on different populations within this metapopulation, and recognizing this diversity is important for accurately assessing risks.  相似文献   

4.
    
Soil micronutrients are capital for the delivery of ecosystem functioning and food provision worldwide. Yet, despite their importance, the global biogeography and ecological drivers of soil micronutrients remain virtually unknown, limiting our capacity to anticipate abrupt unexpected changes in soil micronutrients in the face of climate change. Here, we analyzed >1300 topsoil samples to examine the global distribution of six metallic micronutrients (Cu, Fe, Mn, Zn, Co and Ni) across all continents, climates and vegetation types. We found that warmer arid and tropical ecosystems, present in the least developed countries, sustain the lowest contents of multiple soil micronutrients. We further provide evidence that temperature increases may potentially result in abrupt and simultaneous reductions in the content of multiple soil micronutrients when a temperature threshold of 12–14°C is crossed, which may be occurring on 3% of the planet over the next century. Altogether, our findings provide fundamental understanding of the global distribution of soil micronutrients, with direct implications for the maintenance of ecosystem functioning, rangeland management and food production in the warmest and poorest regions of the planet.  相似文献   

5.
Climate change has been predicted to lead to changes in local and regional species richness through species extinctions and latitudinal ranges shifts. Here, we show that species richness of fish in the North Sea, a group of ecological and socio-economical importance, has increased over a 22-year period and that this rise is related to higher water temperatures. Over eight times more fish species displayed increased distribution ranges in the North Sea (mainly small-sized species of southerly origin) compared with those whose range decreased (primarily large and northerly species). This increase in species richness can be explained from the fact that fish species richness in general decreases with latitude. This observation confirms that the interaction between large-scale biogeographical patterns and climate change may lead to increasing species richness at temperate latitudes.  相似文献   

6.
The relative stimulation of photosynthesis by elevated carbon dioxide in C3 species normally increases strongly with increasing temperature. This results from the kinetic characteristics of Rubisco, and has potentially important implications for responses of vegetation to increasing atmospheric carbon dioxide. It is often assumed that because Rubisco characteristics are conservative, all C3 species have the same temperature dependence of the response of photosynthesis to elevated carbon dioxide. However, in this field study of Taraxacum officinale, there were no significant differences in the relative stimulation of photosynthesis by elevated carbon dioxide among days with temperatures ranging from 15 to 34 °C. Nevertheless, short-term measurements indicated a strong temperature dependence of the stimulation. This suggested that acclimation to temperature caused the lack of variation in the seasonal data. Experiments in controlled environments indicated that complete acclimation of the relative stimulation of photosynthesis by elevated carbon dioxide occurred for growth temperatures of 10 – 25 °C. The apparent specificity of Rubisco for carbon dioxide relative to oxygen at 15 °C, as assayed in vivo by measurements of the carbon dioxide concentration at which carboxylation equalled oxygenation, also varied with growth temperature. Changes in the apparent specificity of Rubisco accounted for the acclimation of the temperature dependence of the relative stimulation of photosynthesis by elevated carbon dioxide. It is premature to conclude that low temperatures will necessarily reduce the relative stimulation of photosynthesis caused by rising atmospheric carbon dioxide. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

7.
    
The first decade of the new millennium saw a flurry of experiments to establish a mechanistic understanding of how climate change might transform the global biota, including marine organisms. However, the biophysical properties of the marine environment impose challenges to experiments, which can weaken their inference space. To facilitate strengthening the experimental evidence for possible ecological consequences of climate change, we reviewed the physical, biological and procedural scope of 110 marine climate change experiments published between 2000 and 2009. We found that 65% of these experiments only tested a single climate change factor (warming or acidification), 54% targeted temperate organisms, 58% were restricted to a single species and 73% to benthic invertebrates. In addition, 49% of the reviewed experiments had issues with the experimental design, principally related to replication of the main test‐factors (temperature or pH), and only 11% included field assessments of processes or associated patterns. Guiding future research by this inventory of current strengths and weaknesses will expand the overall inference space of marine climate change experiments. Specifically, increased effort is required in five areas: (i) the combined effects of concurrent climate and non‐climate stressors; (ii) responses of a broader range of species, particularly from tropical and polar regions as well as primary producers, pelagic invertebrates, and fish; (iii) species interactions and responses of species assemblages, (iv) reducing pseudo‐replication in controlled experiments; and (v) increasing realism in experiments through broad‐scale observations and field experiments. Attention in these areas will improve the generality and accuracy of our understanding of climate change as a driver of biological change in marine ecosystems.  相似文献   

8.
There is considerable interest in understanding how ectothermic animals may physiologically and behaviourally buffer the effects of climate warming. Much less consideration is being given to how organisms might adapt to non-climatic heat sources in ways that could confound predictions for responses of species and communities to climate warming. Although adaptation to non-climatic heat sources (solar and geothermal) seems likely in some marine species, climate warming predictions for marine ectotherms are largely based on adaptation to climatically relevant heat sources (air or surface sea water temperature). Here, we show that non-climatic solar heating underlies thermal resistance adaptation in a rocky–eulittoral-fringe snail. Comparisons of the maximum temperatures of the air, the snail''s body and the rock substratum with solar irradiance and physiological performance show that the highest body temperature is primarily controlled by solar heating and re-radiation, and that the snail''s upper lethal temperature exceeds the highest climatically relevant regional air temperature by approximately 22°C. Non-climatic thermal adaptation probably features widely among marine and terrestrial ectotherms and because it could enable species to tolerate climatic rises in air temperature, it deserves more consideration in general and for inclusion into climate warming models.  相似文献   

9.
    
Anthropogenic climate change poses substantial challenges to biodiversity conservation. Effects of climate change on summer conditions and associated heat and desiccation stress have attracted much research interest, while the implications of changing winter conditions on hibernation have hitherto received fairly little attention. This is surprising as the latter may also strongly affect biodiversity. By investigating the effects of overwintering conditions on diapause and postdiapause survival in a temperate-zone butterfly, we found that warmer and moister winter conditions substantially decreased survival rates. However, detrimental effects were restricted to survival during diapause and subsequent development and had no clear effects on butterfly performance. We suggest that overwintering survival is an important driver of vulnerability to climate change. Our study stresses the importance of collating more data on overwintering survival in species with different hibernation strategies to predict the impact of ongoing climate change on biodiversity.  相似文献   

10.
    
The deteriorating state of the environment and global warming pose a serious and unprecedented threat to humanity. Yet, public response and personal behavior do not reflect the proportions of such a threat. In the present research we explored possible reasons for this discrepancy. Past research has shown that people perceive events as more threatening based on their immediacy, certainty, or personal implications. Liberman and Trope (2008) developed the concept of “psychological distance” (PD), according to which more immediate events are seen as “closer in time,” more certain events as “closer in probability,” and events with greater potential for personal harm as “socially closer.” Adopting this concept, we examined how distant, in terms of PD, people perceive environmental threats to be. Using a structural equations model, we measured how PD influences environmental threat perception. In a sample of 305 Israeli students who completed a computerized questionnaire, we found that environmental threats were perceived as psychologically distant in all of the PD dimensions, and that PD strongly affected perceived severity of environmental threats and willingness to engage in pro-environmental behavior. The reasons for the psychological remoteness of environmental threats and possible approaches to cope with its implications are discussed.  相似文献   

11.
  总被引:2,自引:0,他引:2  
Mean temperature of establishment years for warm‐ and cold‐year subpopulations of a naturally occurring stand of Betula pendula (birch) shows a difference equivalent to that between current temperatures and temperatures projected for 35–55 years hence, given ‘business as usual.’ The existence of ‘pre‐adapted’ individuals in standing tree populations would reduce temperature‐based advantages for invading species and, if general, bring into question assumptions currently used in models of global climate change. Our results demonstrate a methodology useful for investigating the important ecological issue of adaptation vs. range shifts as a means of response to climate change.  相似文献   

12.
There is ample evidence for ecological responses to recent climate change. Most studies to date have concentrated on the effects of climate change on individuals and species, with particular emphasis on the effects on phenology and physiology of organisms as well as changes in the distribution and range shifts of species. However, responses by individual species to climate change are not isolated; they are connected through interactions with others at the same or adjacent trophic levels. Also from this more complex perspective, recent case studies have emphasized evidence on the effects of climate change on biotic interactions and ecosystem services. This review highlights the ‘knowns’ but also ‘unknowns’ resulting from recent climate impact studies and reveals limitations of (linear) extrapolations from recent climate-induced responses of species to expected trends and magnitudes of future climate change. Hence, there is need not only to continue to focus on the impacts of climate change on the actors in ecological networks but also and more intensively to focus on the linkages between them, and to acknowledge that biotic interactions and feedback processes lead to highly complex, nonlinear and sometimes abrupt responses.  相似文献   

13.
杨玉盛 《生态学报》2017,37(1):1-11
随着全球环境变化和人类活动对生态系统影响的日益加深,生态系统结构和功能发生强烈变化,生态系统提供各类资源和服务的能力在显著下降。在这种背景下,全面认识生态系统的结构功能与全球环境变化的关系已成为当前生态学研究的热点之一。本文综述了全球环境变化对典型生态系统(包括森林生态系统、河口湿地生态系统、城市生态系统)影响以及全球环境变化适应的研究现状,分析研究面临的困难及挑战。在此基础上,提出对未来研究发展趋势的展望。在森林生态系统与全球环境变化研究上,未来应重视能更好模拟现实情景的、多因子、长期的全球环境变化控制试验,并注重不同生物地球化学循环之间的耦合作用。在湿地生态系统与全球环境变化研究上,未来应加强氮沉降、硫沉降及盐水入侵对湿地生态系统碳氮循环的影响,明晰滨海湿地的蓝碳功能,加强极端气候和人类干扰影响下湿地生态系统结构和功能变化及恢复力的研究。在城市生态系统与全球环境变化研究上,未来应深化城市生物地球化学循环机制研究,实现城市生态系统的人本需求侧重与转向,并开展典型地区长期、多要素综合响应研究。在全球环境变化适应研究上,未来应构架定量化、跨尺度的适应性评价体系,加强典型区域/部门的适应性研究以及适应策略实施的可行性研究,注重适应与减缓对策的关联研究及实施的风险评估。期望本综述为我国生态系统与全球环境变化研究提供一些参考。  相似文献   

14.
气温上升对草地土壤微生物群落结构的影响   总被引:11,自引:3,他引:11       下载免费PDF全文
张卫建  许泉  王绪奎  卞新民 《生态学报》2004,24(8):1742-1747
在 2 0世纪内 ,全球气温已经上升了 0 .6℃ ,并预计到本世纪末仍将上升 1.4~ 5 .8℃。全球气候变暖对生态系统的潜在影响 ,生态系统对气温上升的反馈已成为国际生态学界的研究热点 ,而且所研究的系统也已经从过去简化的模拟系统到复杂的真实生态系统。但是 ,现有对真实生态系统的研究大部分集中在地上植物群落和土壤气体交换等领域 ,对在土壤有机碳分解和保护中起决定作用的土壤微生物研究较少。为此 ,在美国大平原地区进行人工提高气温 (上升 1.8℃ ) ,来研究土壤微生物对气温上升的反应。结果表明 :增温对土壤微生物的总生物量没有显著效应 ,但可以提高微生物的 C∶ N比。另外 ,磷脂肪酸分析发现 ,气温上升显著降低土壤微生物量中的细菌比重 ,提高真菌的份额 ,从而显著提高了群落中真菌与细菌的比值。而且 ,通过对土壤微生物底物利用方式和磷脂肪酸特征的主成份分析 ,发现增温导致了土壤微生物群落结构的转变。可见 ,气温上升可能是通过提高土壤微生物中真菌的优势 ,而导致群落结构的变化。该变化将可以提高微生物对土壤有机碳的利用效率 ,并利于土壤有机碳的保护  相似文献   

15.
In highly seasonal environments, offspring production by vertebrates is timed to coincide with the annual peak of resource availability. For herbivores, this resource peak is represented by the annual onset and progression of the plant growth season. As plant phenology advances in response to climatic warming, there is potential for development of a mismatch between the peak of resource demands by reproducing herbivores and the peak of resource availability. For migratory herbivores, such as caribou, development of a trophic mismatch is particularly likely because the timing of their seasonal migration to summer ranges, where calves are born, is cued by changes in day length, while onset of the plant-growing season on the same ranges is cued by local temperatures. Using data collected since 1993 on timing of calving by caribou and timing of plant growth in West Greenland, we document the consequences for reproductive success of a developing trophic mismatch between caribou and their forage plants. As mean spring temperatures at our study site have risen by more than 4 degrees C, caribou have not kept pace with advancement of the plant-growing season on their calving range. As a consequence, offspring mortality has risen and offspring production has dropped fourfold.  相似文献   

16.
董兆克  戈峰 《昆虫知识》2011,48(5):1141-1148
全世界地表平均温度在上个世纪增加了0.74℃,并且在未来还会持续增加。在过去的20年,气候变暖对生物系统的影响吸引了大量的研究。本文综述了由温度升高为主要驱动因子的气候变化对昆虫适合度的影响,主要从昆虫越冬存活率、化性(世代数)、扩散迁移、发生分布、物候关系5个方面阐述气候变暖对昆虫发生发展的作用,认为未来应长期进行昆虫种群动态监测预警,更关注气候变暖下植物-害虫-天敌互作关系的研究。  相似文献   

17.
18.
    
Aim Land use and climate are two major components of global environmental change but our understanding of their simultaneous and interactive effects upon biodiversity is still limited. Here, we investigated the relationship between the species richness of neophytes, i.e. non‐native vascular plants introduced after 1500 AD, and environmental covariates to draw implications for future dynamics under land‐use and climate change. Location Switzerland, Central Europe. Methods The distribution of vascular plants was derived from a systematic national grid of 1 km2 quadrates (n = 456; Swiss Biodiversity Monitoring programme) including 1761 species, 122 of which were neophytes. Generalized linear models (GLMs) were used to correlate neophyte species richness with environmental covariates. The impact of land‐use and climate change was thereafter evaluated by projections for the years 2020 and 2050 using scenarios of moderate and strong changes for climate warming (IPCC) and urban sprawl (NRP 54). Results Mean annual temperature and the amount of urban areas explained neophyte species richness best, with a high predictive power of the corresponding model (cross‐validated D2 = 0.816). Climate warming had a stronger impact on the potential increase in the mean neophyte species richness (up to 191% increase by 2050) than ongoing urban sprawl (up to 10% increase) independently from variable interactions and model extrapolations to non‐analogue environments. Main conclusions In contrast to other vascular plants, the prediction of neophyte species richness at the landscape scale in Switzerland requires few variables only, and regions of highest species richness of the two groups do not coincide. The neophyte species richness is basically driven by climatic (temperature) conditions, and urban areas additionally modulate small‐scale differences upon this coarse‐scale pattern. According to the projections climate warming will contribute to the future increase in neophyte species richness much more than ongoing urbanization, but the gain in new neophyte species will be highest in urban regions.  相似文献   

19.
The global environment is changing with increasing temperature and atmospheric carbon dioxide concentration, [CO2]. Because these two factors are concomitant, and the global [CO2] rise will affect all biomes across the full global range of temperatures, it is essential to review the theory and observations on effects of temperature and [CO2] interactions on plant carbon balance, growth, development, biomass accumulation and yield. Although there are sound theoretical reasons for expecting a larger stimulation of net CO2 assimilation rates by increased [CO2] at higher temperatures, this does not necessarily mean that the pattern of biomass and yield responses to increasing [CO2] and temperature is determined by this response. This paper reviews the interactions between the effects of [CO2] and temperature on plants. There is little unequivocal evidence for large differences in response to [CO2] at different temperatures, as studies are confounded by the different responses of species adapted and acclimated to different temperatures, and the interspecific differences in growth form and development pattern. We conclude by stressing the importance of initiation and expansion of meristems and organs and the balance between assimilate supply and sink activity in determining the growth response to increasing [CO2] and temperature.  相似文献   

20.
1. Hyphantria cunea Drury invaded Japan at Tokyo in 1945 and expanded its distribution gradually into northern and south-western Japan. All populations in Japan were bivoltine until the early 1970s, at which time trivoltine populations appeared in several southern regions. Presently, H. cunea exists as separate bivoltine and trivoltine populations divided around latitude 36 degrees . In the course of this voltinism change, the mean surface temperature in Japan rose by 1.0 degrees C. 2. To determine whether and how this temperature increase might be responsible for the voltinism change, we constructed an age-structured model incorporating growth speed driven by actual daily temperature and detailed mechanisms of diapause induction triggered by both daily photoperiod and temperature. 3. The simulation result suggests that both the acceleration of the growth speed and the prolongation of diapause induction are necessary to cause changes in voltinism, regardless of temperature increase. We concluded that the H. cunea population changed its life-history traits as an adaptation parallel with its invasion into the south-western parts of Japan. 4. Though the temperature increase had little effect on the fitness and heat stress in bivoltine and trivoltine populations, the trivoltine life cycle has become advantageous at least in marginal regions such as Tokyo.  相似文献   

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