气候变化对植物有性生殖影响的研究进展

植物对全球气候变化的响应近年来已成为植物学研究热点之一,而有性生殖阶段对环境的变化最敏感。本文较系统地综述了过去数十年气候变化主要因子温度、温室气体、紫外线B辐射和气溶胶对植物花期、授粉受精和生殖产量等有性生殖过程的影响。主要概括:(1)温度适度升高促使大部分植物花期提前,加速授粉受精过程,但同时使传粉者活动期和花期分离而影响授粉受精,其部分增加生殖产量,但温度过高则减少产量。(2)温室气体中水汽过多或过少都减少植物生殖产量;CO2浓度升高一般有利于植物授粉受精,增加生殖产量;O3浓度增加则不利于植物生殖生长。(3)增强的UV-B辐射影响植物花期,不利于授粉受精,对生殖产量影响复杂。(4)气溶胶排放量增加对植物生殖产量的影响依据气溶胶浓度、植物冠层结构和环境条件不同而异。最后分析总结了国内外相关研究中仍存在的不足之处,为更好理解和深入研究植物对气候变化的响应机制提供参考。     

Climate Change Effects on Vegetation Distribution and Carbon Budget in the United States

The Kyoto protocol has focused the attention of the public and policymarkers on the earth's carbon (C) budget. Previous estimates of the impacts of vegetation change have been limited to equilibrium “snapshots” that could not capture nonlinear or threshold effects along the trajectory of change. New models have been designed to complement equilibrium models and simulate vegetation succession through time while estimating variability in the C budget and responses to episodic events such as drought and fire. In addition, a plethora of future climate scenarios has been used to produce a bewildering variety of simulated ecological responses. Our objectives were to use an equilibrium model (Mapped Atmosphere–Plant–Soil system, or MAPSS) and a dynamic model (MC1) to (a) simulate changes in potential equilibrium vegetation distribution under historical conditions and across a wide gradient of future temperature changes to look for consistencies and trends among the many future scenarios, (b) simulate time-dependent changes in vegetation distribution and its associated C pools to illustrate the possible trajectories of vegetation change near the high and low ends of the temperature gradient, and (c) analyze the extent of the US area supporting a negative C balance. Both models agree that a moderate increase in temperature produces an increase in vegetation density and carbon sequestration across most of the US with small changes in vegetation types. Large increases in temperature cause losses of C with large shifts in vegetation types. In the western states, particularly southern California, precipitation and thus vegetation density increase and forests expand under all but the hottest scenarios. In the eastern US, particularly the Southeast, forests expand under the more moderate scenarios but decline under more severe climate scenarios, with catastrophic fires potentially causing rapid vegetation conversions from forest to savanna. Both models show that there is a potential for either positive or negative feedbacks to the atmosphere depending on the level of warming in the climate change scenarios. Received 12 May 2000; accepted 22 November 2000.     

Climate induced increases in species richness of marine fishes

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.     

Climate impacts at multiple scales: evidence for differential population responses in juvenile Chinook salmon

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.     

Predictions of response to temperature are contingent on model choice and data quality

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.     

The Role of Biota in Global Climate Change

The problem of global climate change is analyzed in the context of the balance of interdependent biotic sources and reservoirs of greenhouse gases in the continental part of northern Eurasia. Current problems are identified and the prospects for further studies of the problem are outlined.     

气候变化对鸟类影响：长期研究的意义

过去一个多世纪全球气候发生了明显变化,地球表面温度正在逐渐变暖。已有大量研究结果表明,鸟类已经在种群动态变化、生活史特性以及地理分布范围等方面对全球气候变化作出了相应的反应。根据全球范围内气候变化对鸟类影响的研究资料,尤其是北美和欧洲的一些长期研究项目的成果,综述了气候变化对鸟类分布范围、物候、繁殖和种群动态变化等方面的可能影响。这些长期研究项目为探讨气候变化在个体和种群的水平上如何长时间地影响鸟类提供了独特的机会,对未来中国鸟类学研究也会有所裨益。     

Climate change reduces reproductive success of an Arctic herbivore through trophic mismatch

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.     

亚高山草甸植物群落对气候变化的响应

为了研究气温升高、氮素增加和人为干扰对亚高山草甸植物生长和非结构性碳水化合物(NSC)的影响,该研究采用开顶式生长箱(OTC)模拟增温,同时进行施加氮肥和除草处理,对青藏高原东南缘邛崃山脉东坡巴郎山(四川盆地向青藏高原的过渡地带)的亚高山草甸植物的生长和NSC含量进行测定分析。结果显示:(1)各处理土壤全磷(P)和全钾(K)含量与对照均无显著差异,增温加施肥处理的土壤全氮(N)含量与对照无显著差异,但增温处理、施肥处理、除草处理、增温加除草处理、施肥加除草处理和增温加施肥加除草处理的土壤全氮含量较对照均显著降低。(2)增温促进禾本科和杂类草功能群生长,抑制莎草科功能群生长,提高禾本科功能群重要值,降低杂类草功能群重要值,且对莎草科功能群重要值的作用受施氮和除草的影响;施肥促进禾本科和杂类草功能群的高生长,并且促进莎草科功能群生长;除草促进莎草科功能群生长,抑制禾草科和杂类草功能群的生长;而施肥和除草的交互作用有利于禾草科功能群生长,施肥和除草都提高了莎草科功能群的重要值,降低了禾草科功能群的重要值。(3)不同物种NSC含量及分配对于各处理的响应有所不同,紫地榆的NSC含量与物种分盖度相关性显著,珠芽蓼的NSC含量与物种高度相关性显著。研究表明,气候变暖和土壤氮素增加有利于禾本科和莎草科植物的生长,并使植物改变体内非结构性碳水化合物的分配来抵御环境压力。     

全球气候变化对沈阳地区春玉米生长的可能影响

利用玉米（Ｚｅａ ｍａｙｓ Ｌ．）生长生理生态学模拟模型（ＭＰＥＳＭ）,分别模拟了未来气候变化的１２种气候条件下（ＣＯ２浓度倍增,平均气温上升１．５℃、３．０℃和４．５℃,降水量增加２０％、减少２０％、减少４０％和降水量不变）,沈阳地区土壤湿度、玉米发育和玉米生长的变化,并与当前条件下进行了比较,以评价玉米生长对各气候因子变化的敏感性和全球气候变化下沈阳地区春玉米的生长趋势。研究表明：土壤湿度对降     

全球气候变化对沈阳地区春玉米生长的可能影响

Physiological ecology simulation modelling of maize growth (MPESM) was used to simulate the variation of soil moisture, maize development and maize growth under twelve prescribed climate scenarios, which include doubling CO2, raising mean temperature by 1.5 ℃, 3.0 ℃ and 4.5 ℃, and changing precipitation by 0, +20%, -20%, and -40%. The simulated results were compared with that of the present climate, to assess the sensitivity of maize to climatic change. The analysis indicated that soil moisture is sensitive to reduced precipitation, maize development is sensitive to the rise of temperature, and maize growth is affected greatly by temperature elevation and precipitation variation, which cancel out the positive effects of CO2 elevation. It was found that with the severe change of climate, the leaf biomass, the female fringe biomass, and the leaf area index would decline greatly, and the biomass of stem and root would increase greatly. The average yield of maize will decline between 5% and 30%.     

Climate Change Enhances the Potential Impact of Infectious Disease and Harvest on Tropical Waterfowl

Global warming exacerbates threats to biodiversity as ecological systems shift in response to altered climatic conditions. Yet the long-term survival of populations at direct risk from climate change may also be undermined by local factors such as infectious disease or anthropogenic harvest, which leave smaller and more isolated populations increasingly vulnerable to the rapid pace of global change. We review current and future threats to an exemplar tropical waterfowl species, magpie geese Anseranas semipalmata , and focus on the potential synergies between infectious diseases, harvest, and climate change. We outline viral, bacterial, and fungal pathogens likely to cause disease in geese, and give mention to parasites. Further, we elaborate on a previously developed, spatially explicit population viability model to simulate demographic responses to hunting and novel or enhanced disease outbreaks due to climate change. With no harvest, the simulated disease epizootics only threatened metapopulation viability when both mortality rate was high and outbreaks were regular (a threshold response). However, when contemporary site-specific harvest is included as an additive impact, the response to disease severity and probability was linear. We recommend field research to test these hypotheses linking drivers of waterfowl population decline to disease–climate change interactions.     

适应全球气候变化的中国林业适应对策探讨

全球气候变化对生态系统的影响是当今世界上人们普遍关注的问题[1～3],目前我国林业界正在研究大气二氧化碳浓度增加及全球气候变化对我国林业的影响,并取得了一些研究成果。现有研究表明,全球气候正在变化而且有可能发生更剧烈的变化。因为气候变化是生态因子变化的先兆,进而会影响到林木生长季节的长短、雨量分布、树种分布和进化、边际生境、树木生长、病原体和害虫的活动及火灾发生频度和强度,所以气候变化将对我国林业产生很大的影响[4～6]。为此,研究我国适应全球气候变化的林业对策已是刻不容缓的事。本文在现有研究的基础上,根据我…     

Contrasting Effects of Climate Change on Alpine Chamois

Global climate change can affect animal ecology in numerous ways, but researchers usually emphasize undesirable consequences. Temperature increases, for instance, can induce direct physiological costs and indirect effects via mismatches in resource needs and availability. Species living in mountainous regions, however, could experience beneficial effects because winters might become less severe. We examined the potentially opposing effects of climate change during spring, summer, and winter on recruitment in Alpine chamois (Rupicapra rupicapra). We examined initial recruitment (i.e., the ratio of kids to adult females) and net recruitment (i.e., the ratio of yearlings to adult females) of Alpine chamois through the use of linear mixed effects models and data from block count censuses performed across a 1,500-km² study area in the Italian Alps during summer from 2001 to 2015. Initial recruitment was relatively resistant to the effects of climate change, declining slightly over the study period. We suggest that the effects of increased forage availability and lower snow cover in winter may benefit the reproductive output of adult females, compensating for any negative effects of trophic mismatch and higher temperatures during summer. By contrast, net recruitment strongly declined throughout the study period, consistent with the slight decline of initial recruitment and the negative effects of increasing summer temperatures on the survival of kids during their first winter. These negative effects seemed to outweigh positive effects of climate change, even in a species strongly challenged by winter conditions. These findings provide important information for hunted populations; setting more appropriate hunting bags for yearling chamois should be considered. The ecological plasticity of the chamois, which also inhabits low altitudes, may allow a possible evolutionary escape for the species. © 2020 The Wildlife Society.     

Novel Approaches to Study Climate Change Effects on Terrestrial Ecosystems in the Field: Drought and Passive Nighttime Warming

This article describes new approaches for manipulation of temperature and water input in the field. Nighttime warming was created by reflection of infrared radiation. Automatically operated reflective curtains covered the vegetation at night to reduce heat loss to the atmosphere. This approach mimicked the way climate change, caused by increased cloudiness and increased greenhouse gas emissions, alters the heat balance of ecosystems. Drought conditions were created by automatically covering the vegetation with transparent curtains during rain events over a 2–5-month period. The experimental approach has been evaluated at four European sites across a climate gradient. All sites were dominated (more than 50%) by shrubs of the ericaceous family. Within each site, replicated 4-m × 5-m plots were established for control, warming, and drought treatments and the effect on climate variables recorded. Results over a two-year period indicate that the warming treatment was successful in achieving an increase of the minimum temperatures by 0.4–1.2°C in the air and soil. The drought treatment resulted in a soil moisture reduction of 33%–82% at the peak of the drought. The data presented demonstrate that the approach minimizes unintended artifacts with respect to water balance, moisture conditions, and light, while causing a small but significant reduction in wind speed by the curtains. Temperature measurements demonstrated that the edge effects associated with the treatments were small. Our method provides a valuable tool for investigating the effects of climate change in remote locations with minimal artifacts.     

Effects of Climate Change on Plant Population Growth Rate and Community Composition Change

The impacts of climate change on forest community composition are still not well known. Although directional trends in climate change and community composition change were reported in recent years, further quantitative analyses are urgently needed. Previous studies focused on measuring population growth rates in a single time period, neglecting the development of the populations. Here we aimed to compose a method for calculating the community composition change, and to testify the impacts of climate change on community composition change within a relatively short period (several decades) based on long-term monitoring data from two plots—Dinghushan Biosphere Reserve, China (DBR) and Barro Colorado Island, Panama (BCI)—that are located in tropical and subtropical regions. We proposed a relatively more concise index, Slnλ, which refers to an overall population growth rate based on the dominant species in a community. The results indicated that the population growth rate of a majority of populations has decreased over the past few decades. This decrease was mainly caused by population development. The increasing temperature had a positive effect on population growth rates and community change rates. Our results promote understanding and explaining variations in population growth rates and community composition rates, and are helpful to predict population dynamics and population responses to climate change.     

Climate change‐associated trends in net biomass change are age dependent in western boreal forests of Canada

The impacts of climate change on forest net biomass change are poorly understood but critical for predicting forest's contribution to the global carbon cycle. Recent studies show climate change‐associated net biomass declines in mature forest plots. The representativeness of these plots for regional forests, however, remains uncertain because we lack an assessment of whether climate change impacts differ with forest age. Using data from plots of varying ages from 17 to 210 years, monitored from 1958 to 2011 in western Canada, we found that climate change has little effect on net biomass change in forests ≤ 40 years of age due to increased growth offsetting increased mortality, but has led to large decreases in older forests due to increased mortality accompanying little growth gain. Our analysis highlights the need to incorporate forest age profiles in examining past and projecting future forest responses to climate change.     

Global Change Effects on Plant Chemical Defenses against Insect Herbivores

This review focuses on individual effects of major global change factors, such as elevated CO2, Oa, UV light and temperature,on plant secondary chemistry. These secondary metabolites are well-known for their role in plant defense against insect herbivory. Global change effects on secondary chemicals appear to be plant species-specific and dependent on the chemical type. Even though plant chemical responses induced by these factors are highly variable, there seems to be some specificity in the response to different environmental stressors. For example, even though the production of phenolic compounds is enhanced by both elevated CO2 and UV light levels, the latter appears to primarily increase the concentrations of fiavonoids. Likewise, specific phenolic metabolites seem to be induced by O3 but not by other factors, and an increase in volatile organic compounds has been particularly detected under elevated temperature. More information is needed regarding how global change factors influence inducibility of plant chemical defenses as well as how their indirect and direct effects impact insect performance and behavior, herbivory rates and pathogen attack. This knowledge is crucial to better understand how plants and their associated natural enemies will be affected in future changing environments.