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1.
Data series for bud burst, beginning of flowering and petal fall for 20 species of deciduous trees and conifers at four sites in different regions of southern Norway have been analysed and related to temperature series. On average, the spring phenophases occurred 7 days earlier during the period 1971-2005. The most significant linear trends were observed for the earliest phases. The trends in this period were compared with trends in other periods, the longest one starting in 1927. Those starting in cold decades and ending in 2005 were in most instances statistically significant, whereas hardly any significant trend appeared for series starting in warm decades. This fact showed that the results of trend studies are very sensitive to the choice of starting year. There were significant decadal variations in 40% of the series. The dates of occurrence of the phenophases, varying from the first days of May to the first days of June, correlated with seasonal temperature series, in most cases strongest to mean temperatures for the seasons March-May and April-May. The North Atlantic Oscillation Index (NAOI) for January and February appeared to have some predictive power for the date of occurrence of the recorded phases. The basis for this may be that the oscillations described by the index are of importance for the fulfilment of physiological chilling requirements needed to break bud dormancy. The same genotypes of the trees were grown in region West Norway and in Central Norwegian region; during the period 1965-2005 the trends towards earlier bud burst were more pronounced and steeper at the western site.  相似文献   

2.
As a consequence of global warming, environmental conditions such as temperature and salinity are likely to change in near-shore waters. Early life history phases are expected to be particularly vulnerable to changes in these abiotic variables. To evaluate the effect of multiple stressors on the responses of invertebrate larvae, to conditions anticipated under scenarios of climate change, we examined the cellular responses of embryos of three common rocky intertidal gastropod species to temperature and salinity changes. Encapsulated embryos of each species were exposed for 72 h to six combinations of ecologically realistic temperature and salinity levels (22° and 30 °C and 25, 35 and 45 ppt). Embryonic mortality and the responses of two biomarkers: total antioxidant capacity and lipid peroxidation, were then determined. We predicted that those organisms exposed to physiologically stressful levels of the combined stressors would show the strongest responses. The general trend was that both extremes of salinity (25 and 45 ppt) and high temperature (30 °C) negatively affected the embryos studied inducing oxidative stress and increasing lipid peroxidation, leading to increased embryonic mortality. The intensity of the response remained species-specific, with no clear pattern established as to which species was the most sensitive to salinity and temperature changes. Consequently, climate change induced temperature and salinity changes do exert molecular and physiological effects on early life stages of rocky shore gastropods, however, response to these stressors is species-specific.  相似文献   

3.
Phenological stages of natural species and their use as climate indicators   总被引:7,自引:0,他引:7  
 The objectives of this paper are to: (1) present 10 years of phenological data for nine natural species growing in a Mediterranean-type climate, (2) present threshold temperatures that were derived for the computation of cumulative degree-days (CDD), and (3) evaluate the sensitivity of the nine natural species to weather variability. The study was conducted at the Phenological Research Garden of Oristano, Sardinia, Italy, during the period 1986–96. The observations were made on five typical Mediterranean species and four species that are typical of higher latitudes. The mean annual pattern of phenological events and the CDD from 1 January are given for each development stage. Temperature thresholds were evaluated by comparing the standard deviation about the mean number of days in the development period for each species. A good relationship between timing of phenophase occurrence and temperature was observed for the Mediterranean species, which were little affected by variations in rainfall. Phenological development of the non-native species was affected by springtime rainfall. Accepted: 28 October 1998  相似文献   

4.
5.
In Britain death rates from several important causes, particularly circulatory and respiratory diseases, rise markedly during the colder winter months. This close association between temperature and mortality suggests that climate change as a result of global warming may lead to a future reduction in excess winter deaths. This paper gives a brief introductory review of the literature on the links between cold conditions and health, and statistical models are subsequently developed of the associations between temperature and monthly mortality rates for the years 1968 to 1988 for England and Wales. Other factors, particularly the occurrence of influenza epidemics, are also taken into account. Highly significant negative associations were found between temperature and death rates from all causes and from chronic bronchitis, pneumonia, ischaemic heart disease and cerebrovascular disease. The statistical models developed from this analysis were used to compare death rates for current conditions with those that might be expected to occur in a future warmer climate. The results indicate that the higher temperatures predicted for 2050 might result in nearly 9000 fewer winter deaths each year with the largest contribution being from mortality from ischaemic heart disease. However, these preliminary estimates might change when further research is able to make into account a number of additional factors affecting the relationship between mortality and climate.  相似文献   

6.
Ecological processes are changing in response to climatic warming. Birds, in particular, have been documented to arrive and breed earlier in spring and this has been attributed to elevated spring temperatures. It is not clear, however, how long-distance migratory birds that overwinter thousands of kilometers to the south in the tropics cue into changes in temperature or plant phenology on northern breeding areas. We explored the relationships between the timing and rate of spring migration of long-distance migratory birds, and variables such as temperature, the North Atlantic Oscillation (NAO) and plant phenology, using mist net capture data from three ringing stations in North America over a 40-year period. Mean April/May temperatures in eastern North America varied over a 5°C range, but with no significant trend during this period. Similarly, we found few significant trends toward earlier median capture dates of birds. Median capture dates were not related to the NAO, but were inversely correlated to spring temperatures for almost all species. For every 1°C increase in spring temperature, median capture dates of migratory birds averaged, across species, one day earlier. Lilac (Syringa vulgaris) budburst, however, averaged 3 days earlier for every 1°C increase in spring temperature, suggesting that the impact of temperature on plant phenology is three times greater than on bird phenology. To address whether migratory birds adjust their rate of northward migration to changes in temperature, we compared median capture dates for 15 species between a ringing station on the Gulf Coast of Louisiana in the southern USA with two stations approximately 2,500 km to the north. The interval between median capture dates in Louisiana and at the other two ringing stations was inversely correlated with temperature, with an average interval of 22 days, that decreased by 0.8 days per 1°C increase in temperature. Our results suggest that, although the onset of migration may be determined endogenously, the timing of migration is flexible and can be adjusted in response to variation in weather and/or phenology along migration routes.  相似文献   

7.
羊草物候特征对气候因子的响应   总被引:21,自引:5,他引:16  
研究了内蒙古高原典型草原优势植物羊草的物候特征及其对气候因子的响应,结果表明,3~4月的平均温度与羊草的展叶显著相关,温度每升高1℃,羊草展叶提前4.35d;日照时数与羊草枯黄期显著相关,随着日照时数增加,羊草展叶期推后,枯黄期提前;4~10月平均风速与羊草生长季长相关,平均风速越大,生长期越长。  相似文献   

8.
民勤荒漠区不同生活型植物物候响应气候变暖的差异   总被引:1,自引:0,他引:1  
运用1974年以来民勤荒漠区植物物候观测资料和气象观测资料,将22种植物分别按生长类型划分为乔木、灌木和草本植物3种生活型,再按更新芽着生部位将22种植物划分为高位芽植物、地上芽植物和地面芽植物植物3种生活型,分析了按这2种方法划分的不同生活型植物物候响应气候变化的差异.结果表明:1)不论以哪种方法划分的植物生活型,春季物候响应气温变化的敏感程度均大干秋季;2)按生长类型划分的3种生活型植物之间的物候变化差异较按更新芽着生部位划分的3种生活型植物之间的物候变化差异大,主要表现为乔木和灌木的物候差异较大;3)当地植物的生长期长度、乔木的春季物候提前幅度和高位芽植物的春季物候提前幅度大干其他文献报导;4)更新芽着生部位越高,春季物候响应当月和当年气温变暖越敏感,表明在地面以上、乔木高度以内,距地面越高气温对春季物候的影响越显著.  相似文献   

9.
The discussion on the effects of climate change on human activity has primarily focused on how increasing temperature levels can impair human health. However, less attention has been paid to the effect of increased climate variability on health. We investigate how in utero exposure to temperature variability, measured as the fluctuations relative to the historical local temperature mean, affects birth outcomes in the Andean region. Our results suggest that exposure to a temperate one standard deviation relative to the municipality’s long-term temperature mean during pregnancy reduces birth weight by 20 g. and increases the probability a child is born with low birth weight by a 0.7 percentage point. We also explore potential channels driving our results and find some evidence that increased temperature variability can lead to a decrease in health care and increased food insecurity during pregnancy.  相似文献   

10.
This paper summarises the trends of 943 phenological time-series of plants, fishes and birds gathered from 1948 to 1999 in Estonia. More than 80% of the studied phenological phases have advanced during springtime, whereas changes are smaller during summer and autumn. Significant values of plant and bird phases have advanced 5–20 days, and fish phases have advanced 10–30 days in the spring period. Estonia’s average air temperature has become significantly warmer in spring, while at the same time a slight decrease in air temperature has been detected in autumn. The growing season has become significantly longer in the maritime climate area of Western Estonia. The investigated phenological and climate trends are related primarily to changes in the North Atlantic Oscillation Index (NAOI) during the winter months. Although the impact of the winter NAOI on the phases decreases towards summer, the trends of the investigated phases remain high. The trends of phenophases at the end of spring and the beginning of summer may be caused by the temperature inertia of the changing winter, changes in the radiation balance or the direct consequences of human impacts such as land use, heat islands or air pollution.  相似文献   

11.
利用Thomson Data Analysis软件对Zoology Record数据库中收录的1942篇哺乳动物对气候变化响应领域的期刊论文做了重点分析。以关键词为核心分析了不同哺乳动物物种、不同地质年代的研究热点分布和研究热点演变,以及2001-2005年、2006-2010年、2011-2015年3个年代段中的研究热点的演变规律。结果显示:进入2000年以后,该领域文献呈现逐年递增;研究热点显示出了较强的物种相关性;不同地质年代对应的物种研究有细微变化;3个文献发表年代段的研究热点显示出了该领域的热点演变规律。  相似文献   

12.
We must consider the role of multitrophic interactions when examining species' responses to climate change. Many plant species, particularly trees, are limited in their ability to shift their geographic ranges quickly under climate change. Consequently, for herbivorous insects, geographic mosaics of host plant specialization could prohibit range shifts and adaptation when insects become separated from suitable host plants. In this study, we examined larval growth and survival of an oak specialist butterfly (Erynnis propertius) on different oaks (Quercus spp.) that occur across its range to determine if individuals can switch host plants if they move into new areas under climate change. Individuals from Oregon and northern California, USA that feed on Q. garryana and Q. kelloggii in the field experienced increased mortality on Q. agrifolia, a southern species with low nutrient content. In contrast, populations from southern California that normally feed on Q. agrifolia performed well on Q. agrifolia and Q. garryana and poorly on the northern, high elevation Q. kelloggii. Therefore, colonization of southern E. propertius in higher elevations and some northern locales may be prohibited under climate change but latitudinal shifts to Q. garryana may be possible. Where shifts are precluded due to maladaptation to hosts, populations may not accrue warm‐adapted genotypes. Our study suggests that, when interacting species experience asynchronous range shifts, historical local adaptation may preclude populations from colonizing new locales under climate change.  相似文献   

13.
Pinus sylvestris, the most widely distributed pine species, is commonly used in dendrochronological studies. Based on a lack of studies at its southeastern distribution, we analysed the growth responses of P. sylvestris to temperature and precipitation. We selected 13 sites to study the effects of climate on the growth of Scots pine stands throughout a geographic gradient over time. Trees were sampled from pure stands at different elevations and landscape conditions. The linear and non-linear associations between tree-ring widths and climate variables were calculated with locally specific linear correlation analysis and a mixed generalised additive model. Moving window correlation function was also performed to understand the temporal stability of limiting factors on growth from 1930 to 2013. Our findings showed that early spring temperature (March-April) and late spring-early summer precipitation (May-June) are the major drivers of growth at all sites, where high temperature constraints and high precipitation enhances the growth. Moving window correlation analysis highlighted that the response to precipitation was stationary while temperature changed over time. Our non-linear analysis provided a threshold for March-April temperature. The threshold indicates that the relative additional increment sharply increases up to 7 °C and then slightly decreases.  相似文献   

14.
An understanding of plant responses to fluctuations in environment is critical to predictions of plant and ecosystem responses to climate change. In the northern hemisphere, the northern limits of distribution of major biomes are probably determined by the tolerance of their dominant physiognomic types (e.g., deciduous hardwood trees) to minimum winter temperatures and can thus be predicted from long-term patterns of temperature fluctuations. At a more detailed level, the responses of functional groups of plants to altered climate can be predicted from their known responses to fluctuations in soil resources (nutrients and water) and the expected effect of climatic change on these soil resources. Laboratory and field experiments demonstrate the feasibility of this approach.  相似文献   

15.
河北省草本植物物候特征及其对气候变暖的响应   总被引:3,自引:0,他引:3  
高祺  陈静  阎访  赵卫亮 《生态学杂志》2012,31(3):600-605
以1981—2006年河北省8个国家农业气象观测站的草本植物物候观测资料和47个气象站的地面观测资料为基础,运用EOF和REOF等统计学方法,研究了河北省草本植物物候期的变化特征及其对气候变暖的响应。结果表明:河北省草本植物展叶始期总体呈提前趋势,其中东部沿海平原提前趋势最大,中南部平原次之,西北部山区最小;黄枯始期主要表现出推迟趋势,生长季长度以延长趋势为主;春季气温对展叶始期的影响显著,河北省春季气温上升1℃,草本植物展叶始期提前4.1d;各站点生长季倾向率与年均温倾向率呈正相关,即年均温升幅大的站点,生长季延长的幅度也较大;草本植物物候变化特征及其对气候变暖的响应与木本植物基本一致,研究结果对丰富河北省物候与气候变化关系研究具有一定意义。  相似文献   

16.
气候变暖对陆生植物的影响   总被引:7,自引:4,他引:3  
曾小平  赵平  孙谷畴 《应用生态学报》2006,17(12):2445-2450
温度是影响植物生长、发育和功能的重要环境因子,是调节许多陆地生态系统生物地球化学过程的关键因素之一.全球气候持续变暖直接或间接地对陆生植物产生不同程度的影响.本文从不同方面分析了植物对温度升高及其它生态环境因子变化交互作用下的生理生态适应机制,包括生态系统的土壤呼吸、植物的气体交换、水分关系、生物量和生产力的响应等方面的研究进展,并就未来开展陆生植物对气候变暖响应研究提出加强和改进的设想.  相似文献   

17.
Peck LS 《Marine Genomics》2011,4(4):237-243
There is great concern currently over environmental change and the biotic responses, actual or potential, to that change. There is also great concern over biodiversity and the observed losses to date. However, there has been little focus on the diversity of potential responses that organisms can make, and how this would influence both the focus of investigation and conservation efforts. Here emphasis is given to broad scale approaches, from gene to ecosystem and where a better understanding of diversity of potential response is needed. There is a need for the identification of rare, key or unique genomes and physiologies that should be made priorities for conservation because of their importance to global biodiversity. The new discipline of conservation physiology is one aspect of the many ways in which organismal responses to environmental variability and change can be investigated, but wider approaches are needed. Environmental change, whether natural or human induced occurs over a very wide range of scales, from nanometres to global and seconds to millennia. The processes involved in responses also function over a wide range of scales, from the molecular to the ecosystem. Organismal responses to change should be viewed in these wider frameworks. Within this overall framework the rate of change of an environmental variable dictates which biological process will be most important in the success or failure of the response. Taking this approach allows an equation to be formulated that allows the likely survival of future change to be estimated:Ps=(f(PF)xf(GM)xf(NP)xf(F)xf(D)xf(RA))/(ΔExf(C)xf(PR)xF(HS)),where Ps = Probability of survival; PF = Physiological flexibility; GM = Gene pool modification rate; NP = number in population; F = Fitness; D = Dispersal capability; RA = Resource availability; ΔE = rate of change of the environment; C = Competition; PR = Predation and parasitism; HS = Habitat separation. Functions (f) are used here to denote that factors may interact and respond in a non-linear fashion.  相似文献   

18.
Torti VM  Dunn PO 《Oecologia》2005,145(3):486-495
Many recent studies have shown that birds are advancing their laying date in response to long-term increases in spring temperatures. These studies have been conducted primarily in Europe and at local scales. If climate change is a large-scale phenomenon, then we should see responses at larger scales and in other regions. We examined the effects of long-term temperature change on the laying dates and clutch sizes of six ecologically diverse species of North American birds using 50 years of nest record data. As predicted, laying dates for most (four of six) species were earlier when spring temperatures were warmer. Over the long-term, laying dates advanced over time for two species (red-winged blackbirds, Agelaius phoeniceus and eastern bluebirds, Sialia sialis). Laying date of song sparrows (Melospiza melodia) also advanced with increasing temperature when the analysis was restricted to eastern populations. Neither laying date nor clutch sizes changed significantly over time in the remaining species (American coot, Fulica americana, killdeer, Charadrius vociferous, and American robin, Turdus migratorius), an unsurprising result given the lack of increase in temperatures over time at nest locations of these species. This study indicates that the relationship between climate change and breeding in birds is variable within and among species. In large-scale analyses of North American birds, four of seven species have shown advances in laying dates with increasing temperature (including song sparrows in the east). These variable responses within and among species highlight the need for more detailed studies across large spatial scales.  相似文献   

19.
Governing climate change in cities entails a good understanding of urban vulnerabilities. This research presents an Indicator-based Vulnerability Assessment for 571 European cities. Basing on panel data from Urban Audit database and a set of newly developed indicators, we assessed urban vulnerabilities for the following impact chains: (i) heatwaves on human health; (ii) drought on water planning, and; (iii) flooding (sub-divided into pluvial, fluvial and coastal) on the socio-economic tissue and the urban fabric. Results shed light on the key challenges that specific groups of European cities face in order to better deal with the expected impacts of climate change. This knowledge is a necessary step to advance in the understanding of urban risks to climate change and the development of effective EU policies for urban adaptation.  相似文献   

20.
Concerns are rising about the capacity of species to adapt quickly enough to climate change. In long‐lived organisms such as trees, genetic adaptation is slow, and how much phenotypic plasticity can help them cope with climate change remains largely unknown. Here, we assess whether, where and when phenological plasticity is and will be adaptive in three major European tree species. We use a process‐based species distribution model, parameterized with extensive ecological data, and manipulate plasticity to suppress phenological variations due to interannual, geographical and trend climate variability, under current and projected climatic conditions. We show that phenological plasticity is not always adaptive and mostly affects fitness at the margins of the species' distribution and climatic niche. Under current climatic conditions, phenological plasticity constrains the northern range limit of oak and beech and the southern range limit of pine. Under future climatic conditions, phenological plasticity becomes strongly adaptive towards the trailing edges of beech and oak, but severely constrains the range and niche of pine. Our results call for caution when interpreting geographical variation in trait means as adaptive, and strongly point towards species distribution models explicitly taking phenotypic plasticity into account when forecasting species distribution under climate change scenarios.  相似文献   

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