Seasonal Climate Variability Research Articles

Hydraulic and volume change behaviors of compacted highly expansive soil under cyclic wetting and drying

The wide engineered application of compacted expansive soils necessitates understanding their behavior under field conditions. The results of this study demonstrate how seasonal climatic variation and stress and boundary conditions individually or collectively influence the hydraulic and volume change behavior of compacted highly expansive soils. The cyclic wetting and drying (CWD) process was applied for two boundary conditions, i.e. constant stress (CS) and constant volume (CV), and for a wide range of axial stress states. The adopted CWD process affected the hydraulic and volume change behaviors of expansive soils, with the first cycle of wetting and drying being the most effective. The CWD process under CS conditions resulted in shrinkage accumulation and reduction in saturated hydraulic conductivity ( k sat ). On the other hand, CWD under CV conditions caused a reduction of swell pressure while has almost no impact on k sat . An elastic response to CWD was achieved after the third cycle for saturated hydraulic conductivity ( k sat ), the third to fourth cycle for the volume change potential under the CV conditions, and the fourth to fifth cycle for the volume change potential under the CS conditions. Finally, both swell pressure ( σ s ) and saturated hydraulic conductivity ( k sat ) are not fundamental parameters of the expansive soil but rather depend on stress, boundary and wetting conditions.

Seasonality rather than average temperature explains body size variation in a Neotropical fruit‐eating bat

AbstractWe investigated variation in body size of the widely distributed Neotropical bat Chiroderma villosum across its entire range. Our objective was to verify if the size‐related geographic variation in the species is related to environmental variables. We took 13 measurements of 410 specimens from 198 localities in Mesoamerica and South America, and collected information on latitude, longitude, altitude, precipitation, and temperature, totalling 22 variables. We detected clinal variation in size related to latitude and longitude, with a pattern that conforms to the Bergmann's rule. Clinal variation of size along longitude was influenced by the taxonomic component, with subspecies C. v. jesupi being smaller than C. v. villosum. In contrast the latitudinal cline was explained by temperature seasonality and precipitation, with a 14% increase in size between the north and south extremes of the range. In other words, size of individuals is larger in areas with more seasonal oscillations in temperature and with lower precipitation. Our results support the notion that low temperatures alone do not explain large size of mammals in high latitudes. One hypothesis is that large size is favoured in more seasonal climates because somatic growth is faster when resources are abundant, and also larger animals can endure food scarcity better than small ones. We also postulate that pressures related to interspecific competition and resource use may be more intense in more areas marked by seasonal climatic variations. Specifically, a larger size in seasonal areas may allow individuals to explore a wider niche. We suggest that future approaches, refining regional variation in the diet of C. villosum may serve as a further test to this hypothesis.

Development of a Conceptual Framework for Integrated Vector Management in the Heterogeneous Malaria Ecosystem of Western Kenya Highlands

Malaria heterogeneity in the highlands is due to range of factors including seasonal weather changes, climate variability, land-use changes, topography, drug resistance, and malaria control programs. High coverage of long lasting insecticide treated nets is the basis of vector control in epidemic prone western Kenya highlands. Long lasting insecticide treated nets have effectively controlled malaria in the hypo-endemic zones, but not in meso-endemic and hyper-endemic zones where significant residue of transmission remains despite control efforts. Inadequate policy on integrated vector management application for ecologically heterogeneous ecosystems hinders effective malaria control. Advances in ecological and epidemiological studies have improved our understanding on vector distribution determinants and malaria transmission enabling us to effectively integrate indoor residual spraying into the existing long lasting insecticide treated nets programme. Data on malaria vector abundance and parasite prevalence for different malaria ecosystems within western Kenya highlands before and after mass insecticide treated bed-net distribution campaigns was gathered to assess the efficacy of the long lasting insecticide treated nets based control efforts. Field tests were carried out to determine the impact of combined indoor residual spray and long lasting insecticide treated nets on vector indoor resting densities in zones where insecticide treated nets alone had limited efficacy or zero efficacy was observed. Female An. gambiae s.l resting densities of 0.1 mosquitoes/ house/night were associated with a plasmodium falciparum (pf) prevalence rate of 10% or below. This observation enabled the development of a framework for the inclusion of indoor residual spray in integrated vector management with the suggestion that IRS should be applied in malaria eco-epidemiological zones where An. gambiae s.l resting densities exceeds 0.1 females/ house/ night. Similarly, only those houses with a resting density of 0.1 females An. gambiae s.l and above should be targeted during spraying. Such an approach would significantly reduce the cost associated with indoor residual spray and provides a rationale for judicious integration of indoor residual spray within existing long lasting insecticide treated nets control programmes.

Climatic triggers of the phenophases of Elaphoglossum macrophyllum in Southern Brazil

Abstract Although ferns have a prominent floristic position with their richness center in Atlantic Forest in Brazil, the effect of climate on their phenophases is still poorly known. This group shows different phenological patterns due to the great latitudinal extent, the strong climatic seasonality of this forest, and the leaf dimorphism found in some species. In this scenario, we evaluated the phenological events of Elaphoglossum macrophyllum and related them to climatic factors. Fertility, leaf renewal, and leaf senescence in E. macrophyllum were analyzed based on the monthly survey of 152 plants growing for two years in the subtropical Atlantic Forest, Brazil. The three analyzed phenophases showed the same intra-annual pattern regarding continuity, regularity, and seasonality along the two years, revealing a phenological pattern for the specie. The generalized additive models for location, scale, and shape (GAMLSS) indicated that photoperiod was the most important trigger for fertility and leaf renewal. Temperature, as an important phenology modulator, was related to leaf renewal and senescence. Our data indicate that E. macrophyllum, an endangered species in southern Brazil, withstands the consequences of seasonal climatic variations without the individual mortality, total leaf shedding, or fertility loss.

Regional integrated assessment of climate change impact on cotton production in a semi-arid environment

Climate change has a negative impact on the productivity of agricultural crops at local, regional and global levels. Foodstuff security and sustainable livelihood of cotton farmers in the core cotton growing region in Punjab, Pakistan is under threat because of decreased yield due to climate change. The quantification of the integrated impact assessment of climate change for developing adaptation approaches for cotton is vital for improving productivity at a regional level and improving food security at a national level. Two crop models were evaluated with on-farm survey data of 165 farms employing stratified random sampling techniques. Representative agricultural pathways (RAPs) were developed for characterizing future cotton production. Global climate models (GCMs) depicted a rise of 3.6 and 4.3°C for maximum and minimum temperature, respectively, along with a decreased in rainfall of 600 mm under Representative Concentration Pathway (RCP) 8.5. The expected temperature rise for the hot-dry climate would cause a reduction in productivity of 35.3 and 39.2% by mid-century for RCP4.5 and RCP8.5, respectively, according to the Decision Support System for Agrotechnology Transfer (DSSAT) model, while the Agricultural Production System Simulator (APSIM) showed a reduction of 51.1 and 59.6%, respectively. Increases under the current adaptation of a 15% increase in each of nitrogen and planting density ranged from 1.1 to 6.3% for DSSAT and 2.6 to 8.2% for APSIM. Climate-adapted cotton productivity was projected to rise from 18.7 to 35.9% for DSSAT and from 13.8 to 42% for APSIM for all GCMs. Results showed that current and future cotton systems are adversely impacted by climate change; however, climate-change-adapted management approaches could offset possible reductions in productivity. Sustained cotton productivity in the core cotton zone requires capacity building amongst farmers, enabling them to improve their crop management in the face of seasonal climate variability and future climate change.

Effects of diversity on thermal niche variation in bird communities under climate change

Climate change alters ecological communities by affecting individual species and interactions between species. However, the impacts of climate change may be buffered by community diversity: diverse communities may be more resistant to climate-driven perturbations than simple communities. Here, we assess how diversity influences long-term thermal niche variation in communities under climate change. We use 50-year continental-scale data on bird communities during breeding and non-breeding seasons to quantify the communities’ thermal variability. Thermal variability is measured as the temporal change in the community’s average thermal niche and it indicates community’s response to climate change. Then, we study how the thermal variability varies as a function of taxonomic, functional, and evolutionary diversity using linear models. We find that communities with low thermal niche variation have higher functional diversity, with this pattern being measurable in the non-breeding but not in the breeding season. Given the expected increase in seasonal variation in the future climate, the differences in bird communities’ thermal variability between breeding and non-breeding seasons may grow wider. Importantly, our results suggest that functionally diverse wildlife communities can mitigate effects of climate change by hindering changes in thermal niche variability, which underscores the importance of addressing the climate and biodiversity crises together.

Progress in high-resolution isotope-ratio analysis of tree rings using laser ablation.

Stable isotope ratio analysis of tree rings has been widely and successfully applied in recent decades for climatic and environmental reconstructions. These studies were mostly conducted at an annual resolution, considering one measurement per tree ring, often focusing on latewood. However, much more information could be retrieved with high-resolution intra-annual isotope studies, based on the fact that the wood cells and the corresponding organic matter are continuously laid down during the growing season. Such studies are still relatively rare, but have a unique potential for reconstructing seasonal climate variations or short-term changes in physiological plant properties, like water-use efficiency. The reason for this research gap is mostly technical, as on the one hand sub-annual, manual splitting of rings is very tedious, while on the other hand automated laser ablation for high-resolution analyses is not yet well established and available. Here, we give an update on the current status of laser ablation research for analysis of the carbon isotope ratio (δ13C) of wood, describe an easy-to-use laser ablation system, its operation and discuss practical issues related to tree core preparation, including cellulose extraction. The results show that routine analysis with up to 100 laser shot-derived δ13C-values daily and good precision and accuracy (ca. 0.1‰) comparable to conventional combustion in an elemental analyzer are possible. Measurements on resin-extracted wood is recommended as most efficient, but laser ablation is also possible on cellulose extracted wood pieces. Considering the straightforward sample preparation, the technique is therefore ripe for wide-spread application. With this work, we hope to stimulate future progress in the promising field of high-resolution environmental reconstruction using laser ablation.

Seasonal variations in diet (δ13C) and climate (δ18O) inferred through toxodonts enamel teeth during the Late Pleistocene in the brazilian intertropical region

To access the annual isotopic variation of Toxodon platensis Owen, 1837, tooth enamel samples found in tanks in two localities in the Brazilian Intertropical Region (Puxinanã, Paraíba and Caruaru, Pernamuco) was analyzed isotopically (δ13C, δ18O). We suggest that one annual growth cycle of toxodonts could be represented by 11–17 mm of enamel. The carbon and oxygen isotopic values of the studied samples (LEG 2249–2253) are statistically different, interpreted as reflecting different climatic conditions in both localities. The interpretation of the carbon isotopic results shows little variation in the diet. The oxygen isotopic values of all samples represent the record of at least three years under different climate regimes. The carbon and oxygen isotopic values suggested that the feeding behaviour of these toxodonts were not influenced by the prevailing climatic conditions in both localities.

Shifting climate conditions affect recruitment in Midwestern stream trout, but depend on seasonal and spatial context

AbstractClimate change is a complex threat to freshwater ecosystems. Effects on aquatic species will likely differ among populations depending on seasonal and spatial context, which makes a detailed understanding of population responses to shifting climate conditions key to guiding strategic decision‐making. However, few empirical studies have tested for such context dependency on distinct populations across seasons or at large spatial scales. We used 26 years of standardized survey data on recreationally and economically important brook trout (Salvelinus fontinalis) and brown trout (Salmo trutta) in Wisconsin, USA to assess short‐ and long‐term variability in population trends, and quantify the influence of seasonal and spatial climate variability (air temperatures and precipitation) on annual recruitment strength (as indexed by young‐of‐year [YOY] relative abundance in summer). Some short‐term population fluctuations were spatially consistent across the state, indicative of broadscale environmental forcing. Over the longer term, average YOY and age 1 and older brook trout relative abundance has declined since 2006, especially for YOY, while brown trout abundance has substantially increased. The effects of climate conditions on recruitment varied by species, season, and latitude. Increasing maximum summer temperatures were associated with lower brook trout recruitment, but higher brown trout recruitment. The effect for both species was stronger at lower latitudes. Spring temperatures were positively related to brown trout recruitment at lower latitudes; in mid‐latitude and northern streams, they were related to increasing recruitment up to about 1 standard deviation, above which recruitment declined. High and low winter and spring precipitation were associated with precipitous declines in recruitment for both species. By contrast, summer precipitation was positively related to recruitment in northern streams for brook trout and southern streams for brown trout. Our results demonstrate that shifts in climate can affect recruitment in similar species differently depending on temporal (seasonal) and spatial (warm, southern regions compared with cool, northern regions) context. Given trout population trends in Wisconsin and climate projections for the Midwestern United States, location‐ and species‐specific management actions are needed that account for this context dependency. Management should aim to maximize the resiliency of populations to extreme climate conditions by buffering negative influences on recruitment.

Seasonal Climatic Variations Inferred From Pollen in a Laminated Glacier in the Southeastern Tibetan Plateau

AbstractA new, seasonal, laminated ice core pollen record spanning the last 13 years (2000–2012) from Zuoqiupu Glacier (5,600 m a.s.l.), located on the southeastern Tibetan Plateau (TP), reveals clear variations in pollen concentration and assemblage. A total of 117 continuous ice core layers were used for pollen analysis. Samples with high concentrations of Pinus and Tsuga could be identified as layers accumulated in spring, samples with high concentrations of Alnus and Artemisia could be identified as layers accumulated in autumn, and samples rich in herbaceous plant pollen could be regarded as layers deposited in summer. Three peaks of Tsuga pollen concentration accompanied by high Pinus content occurred in the spring of 2003, 2007, and 2010, which corresponded to wetter and warmer conditions modulated by the El Niño decaying phase (April–May in 2003, 2007, and 2010). Thus, pollen grains deposited on the Zuoqiupu Glacier can be used to study the impacts of atmospheric circulations on seasonal climate change over the southeastern TP.

Spatial-Coherent Dynamics and Climatic Signals in the Radial Growth of Siberian Stone Pine (Pinus sibirica Du Tour) in Subalpine Stands along the Western Sayan Mountains

Siberian stone pine (Pinus sibirica Du Tour) is one of the keystone conifers in Siberian taiga, but its radial growth is complacent and thus rarely investigated. We studied its growth in subalpine stands near the upper timberline along the Western Sayan Mountains, Southern Siberia, because climatic responses of trees growing on the boundaries of species distribution help us better understand their performance and prospects under climate change. We performed dendroclimatic analysis for six tree-ring width chronologies with significant between-site correlations at distances up to 270 km (r = 0.57–0.84, p < 0.05). We used ERA-20C (European Reanalysis of the Twentieth Century) daily climatic series to reveal weak but spatially coherent responses of tree growth to temperature and precipitation. Temperature stably stimulated growth during the period from the previous July–August to current August, except for an adverse effect in April. Precipitation suppressed growth during periods from the previous July–September to December (with reaction gradually strengthening) and from the current April to August (weakening), while the snowfall impact in January–March was neutral or positive. Weather extremes probably caused formation of wide tree rings in 1968 and 2002, but narrow rings in 1938, 1947, 1967, 1988, and 1997. A subtle increase in the climatic sensitivity of mature trees was observed for all significant seasonal climatic variables except for the temperature in the previous October–January. The current winter warming trend is supposedly advantageous for young pine trees based on their climatic response and observed elevational advance.

Recent Seasonal Variations in Ecosystem Water Use Efficiency in China's Key Tropical‐Subtropical Transitional Zones in Response to Climate Change

AbstractUnderstanding the response of terrestrial ecosystem water use efficiency (WUE) to climate change is critical to accurately represent the carbon‐water cycle processes. However, how WUE dynamics are evolving under seasonal climate variations and biome‐specific characteristics remains still unclear. In this study, we integrated two state‐of‐the‐art retrieval algorithms to estimate gross primary productivity (GPP) and evapotranspiration (ET) from satellite MODIS records. Such metrics served as input to quantify ecosystem WUE, expressed as the ratio of GPP to ET, and explore its dynamics during the dry and wet season from 2001 to 2018 in China's key tropical to subtropical transitional zones, that is, Yunnan Province. Results show large spatial and seasonal variability in WUE over the observational period. During the dry season, the increasing trends in GPP and ET have led to contrasting WUE patterns in forest and non‐forest biomes, leading to positive and negative WUE trends, respectively. During the wet season, the declining trends in GPP occurring in combination with opposite trends in ET, have caused decreasing WUE consistently across all biomes except croplands, likely further modulated by human factors. The observed changes in WUE appear primarily driven by variations in air temperature (Ta) and vapor pressure deficit (VPD) during both dry and wet seasons. Overall, these results contribute to a better understanding of the carbon‐water interplay in tropical‐subtropical transitional zones and provide new insights to improve our capacity to predict the terrestrial ecosystem's response to climate change.

Spatiotemporal trends in mean and extreme climate variables over 1981–2020 in Meki watershed of central rift valley basin, Ethiopia

Understanding the spatiotemporal changes of climate extremes is essential for managing climatic risk. In the present study, trends of annual and seasonal climate variables along with extreme temperature and precipitation were examined in eight climatic stations of Meki watershed, the Central Rift Valley Basin, Ethiopia during the period 1981 to 2020. A set of 20 precipitation and temperature extreme indices were selected and computed in RClimDex package of the R program to detect climate extreme events. The recent method of Innovative trend analysis, the non-parametric Mann–Kendall trend test, and Sen's slope estimator were applied to evaluate trends of the annual and seasonal precipitation and temperature. The result indicates that the annual precipitation has been decreasing in 71% of climatic stations and 43% of these stations showed a significant trend. The annual minimum temperature declined in 75% of the stations, whereas all stations indicated a significant increasing trend in annual mean maximum temperature. The Mann–Kendall test detected a significant increasing and decreasing trend in most of the temperature and precipitation extreme indices respectively. For the temperature extremes, more frequent warm and fewer cold temperature extremes were observed. In more than 75% of the climatic stations, a considerable drying trend was found for the precipitation extreme indices. Besides, stations with significant warming and drying trends were located in the downstream areas of the watershed. Overall, this study proved that the observed warming trend in mean annual temperature contributed to changes in the normal thresholds of extremes. The change in precipitation and temperature extremes have increased the frequency, intensity, and duration of extreme events in most of the stations. Likewise, climate extreme events that occur more frequently with high intensity are likely to exacerbate climatic risks, which require proper planning of risk management strategies in Meki watershed.

Species richness and asynchrony maintain the stability of primary productivity against seasonal climatic variability.

The stability of grassland communities informs us about the ability of grasslands to provide reliable services despite environmental fluctuations. There is large evidence that higher plant diversity and asynchrony among species stabilizes grassland primary productivity against interannual climate variability. Whether biodiversity and asynchrony among species and functional groups stabilize grassland productivity against seasonal climate variability remains unknown. Here, using 29-year monitoring of a temperate grassland, we found lower community temporal stability with higher seasonal climate variability (temperature and precipitation). This was due to a combination of processes including related species richness, species asynchrony, functional group asynchrony and dominant species stability. Among those processes, functional group asynchrony had the strongest contribution to community compensatory dynamics and community stability. Based on a long-term study spanning 29 years, our results indicate that biodiversity and compensatory dynamics a key for the stable provision of grassland function against increasing seasonal climate variability.

Seasonal Variation of Tropical Savanna Altered Agronomic Adaptation of Stock-6-Derived Inducer Lines

Tropicalization is one of the major objectives in breeding haploid inducers to address the poor adaptation of temperate haploid inducers in doubled haploid production in tropical maize. Gaining a better understanding of weather profiles in targeted agroecology is important. This study aimed to investigate the seasonal variation of tropical savanna climate and its impact on agronomic traits and haploid induction rate (HIR) of Stock-6-derived haploid inducer lines. A total of 14 haploid inducers were evaluated across two typical growing seasons between 2020 and 2021. Weather data were collected on daily minimum and maximum temperatures, relative humidity, precipitation, and solar radiation whereas phenotypic data were recorded on plant phenology, tassel attributes, plant stature, ear components, inducer seed rate (ISR), and HIR. The effects of season, genotype, and genotype by season were significant for all traits except season factor on ISR. Seasonal variation existed where the dry season was more suitable for haploid induction and inducer maintenance, as haploid inducers revealed better agronomic performance and seed set, delayed flowering dates, and higher HIR. Since the crossover performance of haploid inducers over seasons was detected, further implications on genotype selection in each season are discussed.

Serviceability of cut slope and embankment under seasonal climate variations

Serviceability of cut slope and embankment under seasonal climate variations

Dynamic Prediction of Preharvest Strawberry Quality Traits as a Function of Environmental Factors

Fruit quality is of increasing importance for consumers but is a complex trait for growers, as it is affected by environment, genotype, and crop management interactions. Decision support tools, such as computer models that simulate crop growth and development can help optimize production but require further improvement to simulate quality aspects. The goal of this study was to apply the newly developed CROPGRO-Strawberry model in the Decision Support System for Agrotechnology Transfer (DSSAT) model framework and develop a module for the dynamic prediction of quality traits for strawberry. Experimental data from Florida with quality measurements from multiple harvests were correlated with indices based on preharvest weather conditions (temperature, radiation, rainfall) and simulated model parameters (evapotranspiration) during fruit development. Two quality relationships based on linear equations were identified and integrated into the model to simulate strawberry fruit soluble solids content (r2 = 0.89, d = 0.97) and titratable acidity (r2 = 0.55, d = 0.85) based on preharvest temperature. A strategic analysis with historical weather data for a subtropical growing region over a 10-year period showed the importance of seasonal climate variability for simulated strawberry yield and fruit quality across different harvest months. The improved CROPGRO-Strawberry model is the first process-based crop model to predict selected quality traits across multiple harvests throughout the season and can be extended to other crop models for which quality traits are important.

Intra-annual growing season climate variability drives the community intra-annual stability of a temperate grassland by altering intra-annual species asynchrony and richness in Inner Mongolia, China.

Understanding the factors that regulate the functioning of our ecosystems in response to environmental changes can help to maintain the stable provisioning of ecosystem services to mankind. This is especially relevant given the increased variability of environmental conditions due to human activities. In particular, maintaining a stable production and plant biomass during the growing season (intra‐annual stability) despite pervasive and directional changes in temperature and precipitation through time can help to secure food supply to wild animals, livestock, and humans. Here, we conducted a 29‐year field observational study in a temperate grassland to explore how the intra‐annual stability of primary productivity is influenced by biotic and abiotic variables through time. We found that intra‐annual precipitation variability in the growing season indirectly influenced the community intra‐annual biomass stability by its negative effect on intra‐annual species asynchrony. While the intra‐annual temperature variability in the growing season indirectly altered community intra‐annual biomass stability through affecting the intra‐annual species richness. At the same time, although the intra‐annual biomass stability of the dominant species and the dominant functional group were insensitive to climate variability, they also promoted the stable community biomass to a certain extent. Our results indicate that ongoing intra‐annual climate variability affects community intra‐annual biomass stability in the temperate grassland, which has important theoretical significance for us to take active measures to deal with climate change.

No strong evidence that modularity, specialization or nestedness are linked to seasonal climatic variability in bipartite networks

AbstractAimGiven the influence of seasonality on most ecological systems, an emerging research area attempts to understand how community network structure is shaped by seasonal climatic variations. To do so, most researchers conduct their analyses using open networks due to the high cost associated with constructing their own community networks. However, unwanted structural differences from the unique sampling and construction methods used to create each open network likely make comparing these networks a difficult task. Here, with the largest set of open bipartite networks collected to date, we test whether seasonal climatic variations explain network structure while additionally accounting for construction/sampling differences between networks.LocationTrying to approach global.Time periodContemporary.Major taxa studiedPlants and animals.MethodsUsing 723 open bipartite networks, we test whether temperature and/or precipitation seasonality explains (un)weighted metrics of nestedness, modularity or specialization across plant–pollinator, seed‐dispersal, plant–ant, host–parasite or plant–herbivore systems.ResultsGenerally, seasonality only weakly explained network structure: at most 16% of the variation in weighted metrics and 5% of the variation in unweighted metrics. Instead, a control for sampling bias in networks, sampling intensity, often better explained many of the network structural metrics. When limiting our analyses to only intensely sampled networks, however, about 33% of the variation in weighted modularity and specialization was explained by seasonality, but only in plant–pollinator networks.Main conclusionsAltogether, we do not find strong evidence that seasonality explains network structure. Our study also highlights the large amount of structural differences in open networks, likely from the many different sampling and network construction techniques adopted by researchers when constructing networks. Hence, a definitive test for the relationship between network structure and seasonality across large spatial extents will require a dataset free from sampling and other biases, where networks are derived from a consistent sampling protocol that appropriately characterizes communities.

The stationary and non-stationary character of the silver fir, black pine and Scots pine tree-growth-climate relationships

Tree-growth-climate relationships are usually assumed to have a stationary character, i.e., continuous and/or time-independent, along the lifetime of the trees. The fact that non-stationarity, i.e., discontinuous and/or time-variable, is more likely to actually be their general rule, has been often neglected in dendrochronology. Nine silver fir, black pine and Scots pine residual ring-width index chronologies (RWIresidual) and five precipitation- and temperature-derived seasonal climatic variables, covering the 20th century and the beginning of the 21st one, were used in this study. Heat map analyses based on rolling window correlations, using corrected p-values in order to deal with the type I errors (i.e., the multiple testing or comparison problem) and reduce them, were conducted to evaluate the evolution and stability of tree-growth-climate relationships along the lifetime of the trees, i.e., their stationary and/or non-stationary character. The obtained results showed that stationary tree-growth-climate relationships were well conserved within trees belonging to a given genus: positive effects, both at young and mature stages, of Twinter (winter temperature) on the Abies trees and of Psprsum(t) (spring-summer precipitation of the current-to-growth year) on the Pinus trees. Non-stationary tree-growth-climate relationships were instead species- and site-dependent and stopped in the 1970s/1980s/1990s. Growth decoupling from seasonal climatic variables was linked in many cases with climatic anomalies but the obtained results did not yield a general rule in this regard. Heat map analyses based on rolling window correlations proved to be a powerful statistical tool in disentangling between the stationary and/or non-stationary character of the tree-growth-climate relationships. Summarizing, this study puts into perspective the critical aspect of looking at the stationary and/or non-stationary character of the tree-growth-climate relationships if we want to better predict the impact of climate change on the future forest tree growth and dynamics based on past tree-growth-climate relationships.