Increasing Spring Temperatures Research Articles

First egg dates of Tree Swallows ( Tachycineta bicolor ) nesting in boxes in west Michigan advanced with increasing spring temperatures between 1993 and 2018

First egg dates of Tree Swallows ( Tachycineta bicolor ) nesting in boxes in west Michigan advanced with increasing spring temperatures between 1993 and 2018

The timing of reproduction is responding plastically, not genetically, to climate change in yellow‐bellied marmots (Marmota flaviventer)

AbstractWith global climates changing rapidly, animals must adapt to new environmental conditions with altered weather and phenology. The key to adapting to these new conditions is adjusting the timing of reproduction to maximize fitness. Using a long‐term dataset on a wild population of yellow‐bellied marmots (Marmota flaviventer) at the Rocky Mountain Biological Laboratory (RMBL), we investigated how the timing of reproduction changed with changing spring conditions over the past 50 years. Marmots are hibernators with a 4‐month active season. It is thus crucial to reproduce early enough in the season to have time to prepare for hibernation, but not too early, as snow cover prevents access to food. Importantly, climate change in this area has, on average, increased spring temperatures by 5°C and decreased spring snowpack by 50 cm over the past 50 years. We evaluated how female marmots adjust the timing of their reproduction in response to changing conditions and estimated the importance of both microevolution and plasticity in the variation in this timing. We showed that, within a year, the timing of reproduction is not as tightly linked to the date a female emerges from hibernation as previously thought. We reported a positive effect of spring snowpack but not of spring temperature on the timing of reproduction. We found inter‐individual variation in the timing of reproduction, including low heritability, but not in its response to changing spring conditions. There was directional selection for earlier reproduction since it increased the number and proportion of pups surviving their first winter. Taken together, the timing of marmot reproduction might evolve via natural selection; however, plastic changes will also be extremely important. Further, future studies on marmots should not operate under the assumption that females reproduce immediately following their emergence.

Contrasting impacts of climate warming on Himalayan Hemlock growth: Seasonal and elevational variations

Ongoing climate change can have varying impacts on tree growth within the growing season and across their elevation ranges, with important implications for forest ecosystem functions and services. However, our knowledge of these effects on climate-sensitive Himalayan forests is still limited. Here, we explore the elevational changes in climatic factors driving long-term changes in the radial growth of Himalayan Hemlock (Tsuga dumosa), including recent responses to unprecedented climate warming in the central Himalayas. We evaluated several growth parameters, including total ring width, earlywood width, adjusted latewood width, and maximum latewood density, in unique > 400-year-old forests along an elevational gradient of 2500–3100 m on the southern slopes of Dhaulagiri, Nepal. Our findings show that changing climatic conditions, characterized by increasing temperatures and variable precipitation patterns, had a more detrimental effect on Tsuga growth at the edge of its elevation range compared to the optimal mid-elevation zone. Specifically, at lower elevations, the combination of spring and preceding autumn warming restricted earlywood growth, while warmer temperatures in late summer stimulated growth at the mid-elevation site by alleviating the cool growth-limiting conditions caused by high monsoonal precipitation. Furthermore, increased spring temperatures enhance latewood density, while summer warming promotes latewood growth at higher elevations. Additionally, we observed that the recent rise in autumn temperatures has begun to impede Tsuga growth across all elevations. In conclusion, our study reveals that the growth of Tsuga trees is influenced by multiple climatic factors that vary within the growing season and across different parts of its elevation range. Recent spring warming has constrained growth in lower elevations, while higher previous autumn temperatures have reduced growth at both higher and lower boundaries of the species' range. These findings contribute to a better understanding of the complex relationship between climate change and tree growth dynamics, particularly in vulnerable Himalayan forests.

The phenology and clutch size of UK Blue Tits does not differ with woodland composition

The deciduous tree‐herbivorous caterpillar‐insectivorous bird food chain is a well‐studied system for investigating the impacts of climate change across trophic levels. To date, across Europe, most attention has focused on the impacts of increasing spring temperature on changes to phenology in Oak‐dominated (Quercus spp.) woodlands. Paridae species and Pied Flycatcher Ficedula hypoleuca are the most studied secondary consumers, all of which demonstrate an advancement in reproductive phenology with increases in spring temperature. Shifts in climate and phenology may also impact on reproductive investment in clutch size, and the effects of climate on phenology and clutch size may vary depending on woodland composition. To date, the effects of among‐habitat variation in phenology and reproductive investment have received little attention. Insectivorous birds inhabiting woodlands that differ in tree composition may differ in the timing of breeding, due to local tree leafing phenology acting as a cue for egg‐laying date and/or clutch size. Moreover, for most insectivorous birds, woodland composition within a territory is likely to be the main determinant of food availability for both adults and chicks. Consequently, if warming springs affect the temporal patterns of food availability differently across different woodland compositions, this may affect the optimal average local phenology for nesting birds. Here, using data from 34 long‐term (mean 15 years) nest monitoring sites across the UK, we investigate the effect of woodland tree composition and temperature on Blue Tit Cyanistes caeruleus first egg date (FED) and clutch size. We supplemented the nest monitoring data by quantifying woodland composition, at a site level, through modified point counts. We predict that birds breeding in woodlands with greater proportions of late‐leafing species, such as Oak and Ash Fraxinus excelsior, will breed later than those breeding in woodlands with greater proportions of early‐leafing species, such as Birch Betula spp. and Beech Fagus sylvatica. We found no evidence for differences in Blue Tit FED or clutch size in relation to the proportion of any of the tree species investigated, after controlling for temperature and latitude (FED: −3.4 and 2.2, clutch size: −0.4 and − 0.2 eggs for one‐unit increase in temperature and latitude, respectively). In recent decades and across all sites, clutch size has decreased as spring temperatures have increased, a strategy which could allow birds flexibly to adjust their breeding phenology such that nestling demand coincides with peak food availability. The lack of an effect of woodland composition on Blue Tit phenology suggests Blue Tits do not fine‐tune their reproductive phenology to the local tree composition. Whether this lack of evidence for phenological divergence is due to an absence of divergent selection on breeding phenology and clutch size or to gene flow is not clear.

Potential to reduce pesticides in intensive apple production through management practices could be challenged by climatic extremes

Apples are the third most produced fruit in the world, but their production is often pesticide-intensive. Our objective was to identify options for pesticide reduction using farmer records from 2549 commercial apple fields in Austria during five years between 2010 and 2016. Using generalized additive mixed modeling, we examined how pesticide use was related to farm management, apple varieties, and meteorological parameters, and how it affected yields and toxicity to honeybees. Apple fields received 29.5 ± 8.6 (mean ± SD) pesticide applications per season at a rate of 56.7 ± 22.7 kg ha−1, which included a total of 228 pesticide products with 80 active ingredients. Over the years, fungicides accounted for 71 % of the pesticide amounts applied, insecticides for 15 %, and herbicides for 8 %. The most frequently used fungicides were sulfur (52 %), followed by captan (16 %) and dithianon (11 %). Of insecticides, paraffin oil (75 %) and chlorpyrifos/chlorpyrifos-methyl (6 % combined) were most frequently used. Among herbicides, glyphosate (54 %), CPA (20 %) and pendimethalin (12 %) were most often used. Pesticide use increased with increasing frequency of tillage and fertilization, increasing field size, increasing spring temperatures, and drier summer conditions. Pesticide use decreased with increasing number of summer days with maximum temperatures >30 °C and number of warm, humid days. Apple yields were significantly positively related to the number of heat days, warm humid nights, and pesticide treatment frequency, but were not affected by frequency of fertilization and tillage. Honeybee toxicity was not related to insecticide use. Pesticide use and yield were significantly related to apple varieties. Our analysis shows that pesticide use in the apple farms studied can be reduced by less fertilization and tillage, partly because yields were >50 % higher than the European average. However, weather extremes related to climate change, such as drier summers, could challenge plans to reduce pesticide use.

气候变化对北京常见树种春季萌芽的影响——基于控制实验研究

PDF HTML阅读 XML下载 导出引用 引用提醒 气候变化对北京常见树种春季萌芽的影响——基于控制实验研究 DOI: 10.5846/stxb202112183591 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家杰出青年基金项目（42025101）；高等学校学科创新引智计划项目（B18006） Effects of climate change on spring budburst of typical tree species in Beijing based on manipulative experiments Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:气候变化对植物物候产生了重要影响，春季萌芽时间的变化不仅会通过改变植物的光合作用影响碳汇能力，还会通过改变群落内的种间关系影响生态系统结构和功能。因此，掌握群落内不同树种春季萌芽对气候变化的响应对于深刻理解物候时间位分化、认识陆地生态系统碳水循环和能量平衡具有重要意义。为提高春季物候模型的预测精度，阐明气候变化对不同树种春季萌芽的影响，以鹅耳枥（Carpinus turczaninowii）、黑桦（Betula dahurica）、华北落叶松（Larix principis-rupprechtii）、糠椴（Tilia mandshurica）和元宝枫（Acer truncatum）5个温带森林的典型树种为研究对象，通过剪枝实验分析了冬季冷激、春季温度和光周期对枝条春季萌芽时间的影响。结果表明，温度升高和冷激增加显著提前了所有树种的春季萌芽时间，从5℃到20℃，春季萌芽时间平均提前了54.5 d；在较高的冷激条件下，春季萌芽时间平均缩短了17.8 d；光周期对各树种春季萌芽时间均没有显著影响，8 h和16 h光周期条件下各树种平均萌芽时间分别为30.3和30.5 d。此外，随着温度升高，5个树种萌芽时间间隔显著缩短，这主要是由于温度升高萌芽热量需求降低导致的，冷激对树种间萌芽时间间隔无显著影响。在气候变暖背景下，森林群落中不同树种萌芽时间间隔将显著缩短，进而影响物候时间生态位分化，导致种间竞争加剧。研究阐明了气候变化对温带阔叶树种春季萌芽及其时间间隔的影响，为气候变化条件下森林生态系统群落动态及森林可持续经营与管理策略的制定提供了理论支撑。 Abstract:Climate change has caused substantial effects on plant phenology over the past decades. Shifts in spring budburst not only affect carbon sink capacity by changing plants' photosynthesis but also influence the structure and function of the ecosystem by altering the relationship between species within the forest community. Understanding how spring budburst of different species respond to climate change is thus essential to improve our knowledge of phenological temporal niche differentiation, carbon and water cycles, as well as the energy balance of terrestrial ecosystems. In order to improve the ability of the spring phenology model and the influence underlying the responses of spring budburst to climate change, we selected five typical temperate tree species in Beijing, i.e. Carpinus turczaninowii, Betula dahurica, Larix principis-rupprechtii, Tilia mandshurica, and Acer truncatum, to test the effects of winter chilling, spring temperature and photoperiod on spring budburst by using twig cutting experiment. We found that photoperiod had no significant effect on spring budburst while increasing spring temperature and winter chilling significantly advanced budburst date. From 5℃ to 20℃, the budburst was advanced by 54.5 days on average, and it was shortened under high chilling conditions by about 17.8 days. The photoperiod had no significant effect on the budburst of each tree species. The average budburst of tree species was 30.3 and 30.5 days under the condition of 8 hours and 16 hours of photoperiod, respectively. In addition, the time interval of budburst between the five tree species was significantly shortened with the spring warming, which might be caused by the heating requirements of budburst under different temperature treatments, which was mainly caused by the decrease of heat requirement for budburst with the increase of temperature, and the chilling had no significant effect on their time interval. Under the background of climate change, the budburst and time interval of budburst between tree species is likely to largely shorten, which would change the differentiation of temporal niche, leading to the increased inter-species competition. This study clarifies the impact of climate change on the budburst and time interval of temperate broad-leaved tree species and provides theoretical support for the formulation of forest ecosystem community dynamics and forest sustainable operation and management strategies under the condition of climate change. 参考文献 相似文献 引证文献

Effects of drought and climate factors on vegetation dynamics in Central Asia from 1982 to 2020

Ecological security and ecosystem stability in Central Asia depend heavily on the local vegetation. Vegetation dynamics and the response and hysteresis relationships to climate factors and drought on multiple scales over long time series in the region still need to be further explored. Using the net primary productivity (NPP) values as the vegetation change index of interest, in this study, we analyzed vegetation dynamics in Central Asia from 1982 to 2020 and assessed the responses and time lags of vegetation to climate factors and drought. The results showed that NPP gradually decreased from north to south and from east to west. Vegetation was distributed along both sides of the mountains. The temperatures rose from northeast to southwest, while precipitation gradually increased from southwest to northeast. The proportion of dry and wet years was as follows: normal (56.41%) > slightly dry (28.2%) > slightly humid (15.39%). Precipitation and drought conditions were positively correlated with NPP during the growing season, while temperature was negatively correlated with NPP. Increased spring temperature, precipitation, and drought conditions positively affected vegetation, while sustained summer temperature resulted in suppressed vegetation growth. Autumn vegetation was positively affected by temperature and drought, and precipitation was negatively correlated with autumn vegetation. Increasing winter temperatures promoted vegetation growth. The time lag between NPP and temperature gradually increased from northeast to southwest, and the time lag between NPP and precipitation gradually increased from south to north. Spring temperatures had the greatest beneficial impact on forestlands; summer climatic factors and drought had little effect on shrublands; the autumn climate exhibited small differences in its influence of each plant type; and winter temperatures had the greatest positive effect on grasslands. No time lag effect was found between any of the four vegetation types and precipitation. A one-month lag was found between cultivated lands and temperature; a two-month lag was found between forestlands and temperature; and a one-month lag was found between forestlands and drought and between shrublands and drought. The results can provide a scientific foundation for the sustainable development and management of ecosystems.

Identifying mechanisms underlying individual body size increases in a changing, highly seasonal environment: The growing trout of West brook.

As air temperature increases, it has been suggested that smaller individual body size may be a general response to climate warming. However, for ectotherms inhabiting cold, highly seasonal environments, warming temperatures may increase the scope for growth and result in larger body size. In a long-term study of individual brook trout Salvelinus fontinalis and brown trout Salmo trutta inhabiting a small stream network, individual lengths increased over the course of 15 years. As size-selective gains and losses to the population acted to reduce body sizes and mean body size at first tagging in the autumn (<60 mm) were not observed to change substantially over time, the increase in body size was best explained by higher individual growth rates. For brook trout, increasing water temperatures during the spring (when both trout species accomplish most of their total annual growth) was the primary driver of growth rate for juvenile fish and the environmental factor which best explained increases in individual body size over time. For brown trout, by contrast, reduction in and subsequent elimination of juvenile Atlantic salmon Salmo salar midway through the study period explained most of the increases in juvenile growth and body size. In addition to these major trends, a considerable amount of interannual variation in trout growth and body size was explained by other abiotic (stream flow) and biotic (population density) factors with the direction and magnitude of these effects differing by season, age-class and species. For example, stream flow was the dominant growth rate driver for adult fish with strong positive effects in the summer and autumn, but flow variation could not explain increases in body size as we observed no trend in flow. Overall, our work supports the general contention that for high-latitude ectotherms, increasing spring temperatures associated with a warming climate can result in increased growth and individual body size (up to a point), but context-dependent change in other factors can substantially contribute to both interannual variation and longer-term effects.

The Prawn Palaemon adspersus in the Hypersaline Lake Moynaki (Crimea): Ecology, Long-Term Changes, and Prospects for Aquaculture

For several years, the prawn Palaemon adspersus population was studied in a hypersaline lake (Crimea) for the first time. P. adspersus is a more halotolerant species than previously thought and can survive and breed up to a salinity of 55 g/L and probably higher. A significant positive correlation was found between the number and biomass of the prawns and the seagrass Ruppia shoot density. The spring temperature increase from 5.5 to 24 °C was accompanied by a significant increase in the prawn number (p = 0.001). In the males and females, the spatial heterogeneity of the distribution of prawns significantly (p = 0.005) negatively correlated with the abundance of prawns. In the period from 2018 to 2021, the area of Ruppia cover and the prawn abundance in the lake decreased, and a significant correlation was found between those changes. High salinity, judging by our data, can reduce the production potential of the species, but the absence of predators in Lake Moynaki allowed the prawns to reach a higher abundance than was observed in other habitats. P. adspersus can be successfully cultivated in hypersaline waters with a salinity up to 55 g/L as a perspective object for Integrated Multi-Trophic Aquaculture. The development of aquaculture in hypersaline waters may help to save freshwater resources, and the development of aquaculture in brines formed during the desalination of seawater will make it more economically viable to obtain freshwater from seawater.

Selection against early flowering in geothermally heated soils is associated with pollen but not prey availability in a carnivorous plant.

In high-latitude environments, plastic responses of phenology to increasing spring temperatures allow plants to extend growing seasons while avoiding late frosts. However, evolved plasticity might become maladaptive if climatic conditions change and spring temperatures no longer provide reliable cues for conditions important for fitness. Maladaptative phenological responses might be related to both abiotic factors and mismatches with interacting species. When mismatches arise, we expect selection to favor changes in phenology. We combined observations along a soil temperature gradient in a geothermally heated area with pollen and prey supplementation experiments and examined how phenotypic selection on flowering time in the carnivorous plant Pinguicula vulgaris depends on soil temperature, and pollen and prey availability. Flowering advanced and fitness decreased with increasing soil temperature. However, in pollen-supplemented plants, fitness instead increased with soil temperature. In heated soils, there was selection favoring later flowering, while earlier flowering was favored in unheated soils. This pattern remained also after artificially increasing pollen and prey availability. Plant-pollinator mismatches can be an important reason why evolved plastic responses of flowering time to increasing spring temperatures become maladaptive under novel environmental conditions, and why there is selection to delay flowering. In our study, selection for later flowering remained after artificially increasing pollen availability, suggesting that abiotic factors also contribute to the observed selection. Identifying the factors that make evolved phenological responses maladaptive under novel conditions is fundamental for understanding and predicting evolutionary responses to climate warming.

Larval Ecology of Gobiid Fishes in a Subtropical Embayment: Environmental Preferences and Spatiotemporal Habitat Partitioning

Larval ecology of gobiid fishes in Xiangshan Bay of the east coast of China was examined from ichthyoplanktonic data collected during 10 weekly cruises in spring–early summer of 2015. Particular attention was given to their environmental preferences and spatiotemporal habitat partitioning. A total of 87, 007 gobiid larval individuals, distributed in 9 species, were collected. The thermal and salinity preferences of 6 of the 9 gobiid larvae have been determined using a quotient-rule analysis. This work filled some gaps in larval ecology of these poorly studied gobiids. Temporal succession in gobiid larvae composition was strongly evident. The bay ecosystem was mainly occupied by Asian freshwater goby Acanthogobius ommaturus, branded goby Chaeturichthys stigmatias and tank goby Glossogobius giuris, with preferences for temperature bellow 19°C during April to early May, while striped sand goby Amoya pflaumi and burrowing goby Trypauchen vagina, which preferred water temperature above 22°C, predominated the larval assemblage in early June. With respect to spatial distribution, relatively little variation was detected among species. Most of gobiid larvae exhibited little obvious habitat preference except pinkgray goby Amblychaeturichthys hexanema and A. ommaturus, which distributed preferably in the inner zone and mouth of the bay ecosystem, respectively. Water temperature was the major structuring factor of gobiid larvae assemblage structure in the bay. The gobiid larvae exhibited to be particularly susceptible to the rapid rising temperature shocks. Sharp decline in the total abundance of gobiid larvae was detected with each rapid heating process. In addition, significant shift in larval fish composition occurred following the process. The results suggest that pattern of temperature increase in spring and early summer plays a vital role in recruitment success of the gobiid larvae.

Seasonal shift in carabid phenology over a period of 18 years

The present study is based on a 20-year study of fields that were previously farmed conventionally and then changed to being farmed organically and a 10-year study of a conventionally farmed field in south-eastern and central Schleswig-Holstein, North Germany, respectively. The carabid beetles were sampled throughout each year using pitfall traps. The analysis aimed to study the changes in the phenology in terms of activity-density associated with changing climate. Climate data revealed an increase in temperature during the period of this study, which was not significant during the single study periods, but significant if a longer period of 70 years is considered. In particular, spring temperatures (March/April) increased. Approximately 36% of the species became active earlier. For 25% of the species their earlier start was not significant but nevertheless associated with temperature increase in spring or the number of cold days (&lt; 0°C) and warm days (&gt; 5°C) in March/April. In total, the earlier start of 69% of the species can in some way be associated with a change in climate in spring. Species with a flexible response to temperature were mostly indifferent to the temperature increase. Comparisons of the data over the 30-year period indicate that the process lasted for at least one to three decades. It is likely that the changes in biological processes caused by global climate change will affect the composition of species and competition between them in the future.

Winter barley grown in a long-term field trial with a large variation in N supply: Grain yield, yield components, protein concentration and their trends

Information on the responsiveness of winter barley to nitrogen (N) is scarce. Based on a long-term field trial (1978–2015) with different winter barley varieties in northern Germany combined with 64 N fertilizer treatments differing in amount (0–360 kg N ha−1) and distribution, the effects of N fertilizer amount and variety on the grain yield and its components, grain protein concentration (GPC), N use efficiency (NUE), and apparent fertilizer N recovery (AFR) were determined. In addition, quadratic N response curves and linear trends over the experimental period (parameters derived from annual N response curves) were estimated. N fertilization increased grain yield in all varieties, mainly due to a larger number of grains m−2 rather than to an improved thousand grain weight (TGW). The newer varieties released since the late 1990s outyielded the older ones, especially at higher N supply, revealing a clear breeding progress, which in turn resulted in an improved NUE and AFR. Only if exceeding 190 kg N ha−1 AFR started to decrease. During the trial, GPC in the unfertilized control significantly decreased, while the yield slightly, but non-significantly increased. In contrast, at economic optimum N supply, a significant increase in grain yield and number of grains m−2 occurred while TGW and GPC remained stable over time. From the practical view of barley growing in humid climates, our results suggest to provide sufficient grains per area (sinks) in order to tap the full yield potential, especially against the background of climate change with its predicted temperature increase in spring and summer impairing grain filling.

Bird-Arrival Dates and Climate Change, Sherbrooke, Quebec

Evidence for earlier spring arrival times of migratory breeding birds is often linked to changing climatic conditions, especially increasing temperatures. Using data collected and recorded in a research diary, this article documents changes in bird-arrival dates within the city of Sherbrooke, QC, Canada. Spring arrival dates of 31 bird species were observed and recorded over a 26-year period, from 1994 to 2019, during a series of 1376 walks along a regular 6.5–7.5-km route. Temperature data for this period were collected from the regional Environment Canada climate station. Arrival dates displayed a strong correlation to changing climate conditions; 28 species had a trend toward arrival dates when correlated to mean temperatures, and this effect was significant in 12 species. Climate change, as indicated by increasing spring temperatures, seems to be having a major influence on the advancement in bird-arrival dates in the spring at this locality.

Shifted dynamics of plankton communities in a restored lake: exploring the effects of climate change on phenology through four decades

Lake surface temperatures have increased globally in recent decades. Climate change can affect lake biota directly via enhanced water temperatures, shorter ice cover duration and prolonged stratification, and indirectly via changes in species interactions. Changes in the seasonal dynamics of phytoplankton and zooplankton can further affect whole lake ecosystems. However, separating the effects of climate change from the more direct and dominating effects of nutrients is a challenge. Our aim was to explore the ecological effects of climate change while accounting for the effects of re-oligotrophication in Lake Mjøsa, the largest lake in Norway. While restoration measures since the 1970s have resulted in strongly reduced nutrient levels, the surface water temperature has increased by almost 0.4°C decade-1 during the same period. We analysed long-term trends and abrupt changes in environmental and biological time series as well as changes in the seasonal dynamics of individual plankton taxa. The general long-term trends in phenology were diverging for phytoplankton (later peaks) vs. zooplankton (earlier peaks). However, individual taxa of both phytoplankton and zooplankton displayed earlier peaks. Earlier peaks of the phytoplankton group Cryptophyceae can be explained by increased spring temperature or other climate-related changes. Earlier onset of population growth of certain zooplankton species (Limnocalanus macrurus and Holopedium gibberum) can also be explained by climatic change, either directly (earlier temperature increase) or more indirectly (earlier availability of Cryptophyceae as a food source). In the long run, climate-related changes in both phytoplankton and zooplankton phenology may have implications for the fish communities of this lake.

Elevation-dependent response of spring phenology to climate and its legacy effect on vegetation growth in the mountains of northwest Mongolia

Vegetation spring phenology in mountains has undergone profound changes due to climate change. In this paper, which made use of the Harmonic Analysis of Time Series (HANTS) smoothing algorithm and logistic models, the start of the vegetation growing season (SOS) inferred from MODIS datasets with different spatial resolutions from 2001 to 2018 was extracted. The MODIS data closest to the ground-truth observation data were then selected to reflect spring phenology. Combined with temperature and precipitation data, the spatio-temporal patterns and elevation-dependent change mechanisms of the SOS and its legacy effect on vegetation growth in the mountains of northwest Mongolia was examined and the following results were obtained: (1) Compared with the MOD13A1 and MOD13A2 datasets, the high spatial resolution MOD13Q1 dataset provided stronger correlations and the lowest errors with ground-truth observation data. (2) In this study, the SOS usually occurred between 120 and 152 day-of-year (DOY) with the earlier SOS detected in the low-elevation areas. Later SOS occurred mostly in the higher elevation areas. (3) The spatio-temporal variations in the SOS are mainly influenced by both spring temperature and winter precipitation, with increasing precipitation in winter tending to delay the SOS, while increasing spring temperature tended to advance the SOS. (4) At elevation gradient, the spring temperature showed a significant negative effect on SOS at all elevations, except between 1037 m and 1137 m and 3337 m to 3437 m above sea level (ASL), with a significant positive correlation between SOS and winter precipitation between 1337 m and 2937 m ASL. It is expected that spring temperature is closely linked to the heat accumulation of plants, while winter precipitation indirectly affects the temperature in spring. (5) In lower elevation areas (below 1437 m ASL), the SOS was found to be negatively correlated with spring and summer growth, with advancing SOS leading to increased vegetation growth during spring and summer. In higher elevation areas (above 1437 m ASL), the SOS was significantly negatively correlated with spring growth and positively correlated with summer growth. Hence, delayed SOS leads to decreased spring growth and increased summer growth. Also, we found the effect of SOS on vegetation growth gradually weakened from spring to summer. These findings can help to determine the mechanisms and functional consequences of spring phenological changes in mountain regions.

The effects of four decades of climate change on the breeding ecology of an avian sentinel species across a 1,500-km latitudinal gradient are stronger at high latitudes.

Global warming affects breeding phenology of birds differentially with latitude, but there is contrasting evidence about how the changing climate influences the breeding of migrating songbirds at their northern breeding range. We investigate the effect of climate warming on breeding time and breeding success of European pied flycatchers Ficedula hypoleuca in Sweden during a period of 36 years using nest reports from bird ringing. To account for the latitudinal variation, we divided Sweden into three latitudinal bands (northern, intermediate, and southern). We applied a sliding window approach to find the most influential period and environment characteristics (temperature, vegetation greenness, and precipitation), using linear mixed models and model averaging. Our results show a long‐term advancement of breeding time related to increasing spring temperature and vegetation greenness during a period before hatching. Northern breeders revealed a larger advancement over the years (8.3 days) compared with southern breeders (3.6 days). We observed a relatively stronger effect of temperature and greenness on breeding time in the north. Furthermore, northern birds showed an increase in breeding success over time, while birds breeding at southern and intermediate latitudes showed reduced breeding success in years with higher prehatching temperatures. Our findings with stronger environment effects on breeding time advancement in the north suggest that pied flycatchers are more responsive to weather cues at higher latitudes. Breeding time adjustment and, potentially, low competition help explain the higher long‐term success observed in the north. Reduced breeding success at more southerly latitudes suggests an inability to match breeding time to very early and warm springs, a fate that with continued climate change could also be expected for pied flycatchers and other long‐distance migrants at their very northern breeding range.

Soil moisture gradients and climate change: predicting growth of a critical boreal tree species

Understanding the complex relationships among climate, tree growth, and water availability is key for predicting the performance of environmentally and economically salient tree species like Pinus banksiana Lamb. Ecologically, P. banksiana occupies the extreme habitats of soil moisture gradient, from very sandy dry soils to waterlogged bogs. However, little is known about how its growth may be affected by future climate in these two habitats. We assessed the effect of climatic variability on the growth of this species under different moisture conditions (sandy dry soils and bogs). Trees in the bog site had the highest growth rates. Individuals in all sites responded positively to increased spring temperature, whereas those in the bog site showed the highest response to increased summer moisture. However, in dry years, growth response in the bog site declined by 17%, whereas in the two drier sites, growth declined between 1% and 9.6%, equalizing growth rates across sites. Further, the decline in growth associated with drier summers eliminated the benefits of warmer springs at the bog site. Sites near bogs are currently associated with high growth performance and are commonly planted with this species. Yet, under the projected climate for the region, trees growing in these sites will likely lose their advantage.

Interaction of climate change with effects of conspecific and heterospecific density on reproduction

We studied the relationship between temperature and the coexistence of great tit Parus major and blue tit Cyanistes caeruleus, breeding in 75 study plots across Europe and North Africa. We expected an advance in laying date and a reduction in clutch size during warmer springs as a general response to climate warming and a delay in laying date and a reduction in clutch size during warmer winters due to density‐dependent effects. As expected, as spring temperature increases laying date advances and as winter temperature increases clutch size is reduced in both species. Density of great tit affected the relationship between winter temperature and laying date in great and blue tit. Specifically, as density of great tit increased and temperature in winter increased both species started to reproduce later. Density of blue tit affected the relationship between spring temperature and blue and great tit laying date. Thus, both species start to reproduce earlier with increasing spring temperature as density of blue tit increases, which was not an expected outcome, since we expected that increasing spring temperature should advance laying date, while increasing density should delay it cancelling each other out. Climate warming and its interaction with density affects clutch size of great tits but not of blue tits. As predicted, great tit clutch size is reduced more with density of blue tits as temperature in winter increases. The relationship between spring temperature and density on clutch size of great tits depends on whether the increase is in density of great tit or blue tit. Therefore, an increase in temperature negatively affected the coexistence of blue and great tits differently in both species. Thus, blue tit clutch size was unaffected by the interaction effect of density with temperature, while great tit clutch size was affected in multiple ways by these interactions terms.

Climatic changes and the fate of mountain herbivores

Mountains are strongly seasonal habitats, which require special adaptations in wildlife species living on them. Population dynamics of mountain ungulates are largely determined by the availability of rich food resources to sustain lactation and weaning during summer. Increases of temperature affect plant phenology and nutritional quality. Cold-adapted plants occurring at lower elevations will shift to higher ones, if available. We predicted what could happen to populations of mountain ungulates based on how climate change could alter the distribution pattern and quality of high-elevation vegetation, using the “clover community-Apennine chamois Rupicapra pyrenaica ornata” system. From 1970 to 2014, increasing spring temperatures (2 °C) in our study area led to an earlier (25 days) onset of green-up in Alpine grasslands between 1700 and 2000 m, but not higher up. For 1970–2070, we have projected trends of juvenile winter survival of chamois, by simulating trajectories of spring temperatures and occurrence of clover, through models depicting four different scenarios. All scenarios have suggested a decline of Apennine chamois in its historical core range, during the next 50 years, from about 28% to near-extinction at about 95%. The negative consequences of climate changes presently occurring at lower elevations will shift to higher ones in the future. Their effects will vary with the species-specific ecological and behavioural flexibility of mountain ungulates, as well as with availability of climate refugia. However, global shifts in distributional ranges and local decreases or extinctions should be expected, calling for farsighted measures of adaptive management of mountain-dwelling herbivores.