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Regional climatic differences increase the complexity of tree radial growth responses to climate change in the monsoon marginal zones and may alter the carbon sequestration capacity of forests. In this study, we collected cores of Pinus tabulaeformis trees at nine sampling sites across different regions. We analysed the relationship between tree-ring width chronology and climatic factors at different sites using dendroecological methods. We used the tree-ring index to calculate resistance, recovery, and resilience as well as to explore the capacity of radial growth to cope with drought events. The results indicate that (1) Drought was the primary factor limiting tree growth, and tree-ring climate response patterns varied across three regions. Tree growth was sensitive to both temperature and precipitation in the eastern Qilian Mountains, while it was more sensitive to temperature in the Hassan Mountains and more sensitive to precipitation in the Helan Mountains. (2) The tree-ring climate response pattern remained unstable over time, and the relative influence of current climate on tree growth increased. (3) The ecological resilience of trees to extreme events varies across three regions, which could be attributed to regional moisture conditions and the duration of drought. In the context of the management and protection of trees in the study area in the future, more attention should be paid to the elasticity of tree growth after drought events., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Avena sterilis L. (A. sterilis) and Avena ludoviciana Dur. (A. ludoviciana) are extremely invasive weeds with strong competitive ability and multiple transmission routes. Both species can invade a variety of dryland crops, including wheat, corn, and beans. Asia, as the world's major food-producing continent, will experience significant losses to agricultural production if it is invaded by these weeds on a large scale. This study used the MaxEnt model and ArcGIS to map the distribution of suitable habitats of the two species in Asia under climate change conditions. The constructed model comprised four levels, with a total of 25 index-level indicator factors used to evaluate the invasion risk of the two species. The results showed that the distribution of suitable habitats for both Avena species was highly dependent on precipitation and temperature. Under climate warming conditions, although overall the total suitable area is predicted to decrease compared to the current period, there are still moderately or highly suitable areas. Asian countries need to provide early warning for areas with significant increases in moderate and highly suitable zones for these two species of weeds under the background of climate change. If there is already an invaded area or if the suitability of the original area is increased, this should be closely monitored, and control measures should be taken to prevent further spread and deterioration., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

The impact of drought on terrestrial ecosystems is increasing, and the spatiotemporal heterogeneity of drought changes exacerbates the difficulty of determining ecosystem responses, especially in arid regions far from oceans. Tree rings have been widely used to understand how forest ecosystems respond to drought. However, the link between local hydroclimate variations related to tree rings and large-scale climate changes is not clear in the Qilian Mountains. Here, we used the tree ring width index to analyze the trend of Picea crassifolia growth and its relationship with climate in the middle Qilian Mountains. The results showed that the radial growth trend of Picea crassifolia is synchronized in the middle Qilian Mountains by calculating the Gleichläufigkeit index (GLK). Our analyses indicated that tree radial growth is positively correlated with drought during the growing season. Tree growth responds stably to drought (scPDSI and SPEI) and precipitation but unstably to temperature during 1950-2019. We further traced the meteorological factors that cause regional drought changes associated with radial growth. An increased total precipitation and decreased evaporation contribute to drought alleviation, favoring an increased tree radial growth. The increased total precipitation is mainly due to increased large-scale precipitation, which is related to water vapor transport changes. This study attempts to explore the influence of large-scale meteorology on regional drought change and its related tree radial growth response, which helps us to better understand the changes in forest ecosystems under climate change., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The northern fringe area of the East Asian summer monsoon (EASM) between arid and semiarid regions is a fragile eco-environment zone and ecological transition zone, and it is highly sensitive to climate change. Predicting the future migration of the northern boundary of the EASM is important for understanding future East Asian climate change and formulating of decisions on ecological protection and economic development in arid and semiarid regions. The reanalysis dataset and simulations of 23 models from the Coupled Models Intercomparison Project Phase 6 (CMIP6) were used to investigate the response of the boundary of the ESAM to the global warming. The multi-model ensemble showed a northwestward migration of the EASM northern boundary during the near-term (2020-2060) and late-term (2061-2099) of the twenty-first century under various Shared Socioeconomic Pathways (SSPs). The northern boundary migrated northwestward by 23-28 and 74-76 km in the near-term and late-term respectively, under SSP1-2.6, 2-4.5 and 3-7.0 and by ~ 44 km and ~ 107 km respectively during the near-term and late-term under SSP5-8.5. During the twenty-first century, under various SSPs, the surface of the East Asian subcontinent warmed more than the ocean, thereby increasing the contrast of near-surface temperature and sea level pressure in summer between the East Asian subcontinent and the surrounding oceans. In turn, the intensified land-sea thermal contrast reinforced the EASM meridional circulation and thus transported more moisture from the Indian Ocean into northern China. Additionally, a poleward migration and weakening of the East Asian subtropical westerly jet would also favor an increase in precipitation, eventually caused a northwestward migration of the EASM northern boundary. The results suggest that the arid and semiarid ecotone will become wetter, which could dramatically improve the eco-environment in the future., (© 2022. The Author(s).)

This study assesses present-day extreme climate changes over China by using a set of phase 6 of the Coupled Model Intercomparison Project (CMIP6) statistical downscaled data and raw models outputs. The downscaled data is produced by the adapted spatial disaggregation and equal distance cumulative distribution function (EDCDF) method at the resolution of 0.25° × 0.25° for the present day (1961-2014) and the future period (2015-2100) under the Shared Socioeconomic Path-way (SSP) 2-4.5 than SSP5-8.5 emission scenario. The results show that the downscaling method improves the spatial distributions of extreme climate events in China with higher spatial pattern correlations, Taylor Skill Scores and closer magnitudes no matter single model or multi model ensemble (MME). In the future projections, large inter-model variability between the downscaled models still exists, particular for maximum consecutive 5-day precipitation (RX5). The downscaled MME projects that total precipitation (PTOT) and RX5, will increase with time, especially for the northwest China. The projected heavy precipitation days (R20) also increase in the future. The region of significant increase in R20 locates in the south of river Yangtze. Maxi-mum annual temperature (TXX) and percentage of warm days (TX90p) are projected to increase across the whole country with larger magnitude over the west China. Projected changes of minimum annual temperature (TNN) over the northeastern China is the most significant area. The higher of the emission scenario, the more significant of extreme climates. This reveals that the spatial distribution of extreme climate events will become more uneven in the future.

To date, few attempts have been made to assess the influence of climate change on forest ecosystems and on the relationship between tree growth and climate in humid areas of low latitudes. In this paper, we studied the response of tree growth and forest ecosystem to climate change by using Fokienia hodginsii tree-ring cores from the northern Yunnan-Guizhou Plateau, southwest of China. Tree growth correlates the highest (r = -0.64, p < 0.01) with mean temperature (July-September), but the coefficients were changing with time as revealed by a moving correlation analysis. Tree growth is significantly (p < 0.05) and positively correlated with January-April mean temperature from AD 1961-1987, while correlations with precipitation are insignificant. In contrast, from 1988 to 2014, tree growth correlated negatively with mean temperature of previous summer and positively with precipitation of previous August-September. This indicated that the limiting factors for tree growth have changed under different climate conditions. The meteorological data suggested that from 1961 to 1987 it was cold and wet in the study area and radial growth is limited by winter and spring temperatures. This restriction is weaker if the climate is appropriate in general. However, from 1988 to 2014, the combined effects of recent warming and decreasing precipitation have led to an increasing response of tree-ring width to drought. In addition, a large proportion of mature F. hodginsii mortality occurred from 2007 to 2013, which corresponds with a drastic reduction of radial growth (narrowest in recent 100 years). The recent drought, induced by decreasing precipitation and increasing temperature, may have passed the threshold which F. hodginsii could tolerate, causing tree growth reduction, tree growth-climate relationship change, as well as catastrophic tree mortality. All these changes may lead to further responses of the local ecosystem to climate change which should be highly regarded.

Defining moisture sources and evolution of precipitation is of significance for further exploration of complex hydro‐climatic interactions, especially under global warming with alternations of evapotranspiration capacity and precipitation moisture source structure. As a sensitive indicator, d‐excess has been widely used to quantify the proportion of recycled vapor to precipitation (fre). However, existing d‐excess‐based models ignore to take transpiration vapor into account and the calculated fre tends to be lower than the true value, thus underestimating the importance of recycled vapor in precipitation. Herein, the existing model was modified with transpiration vapor considered and applied in Guyuan, China located in a monsoon marginal zone with complex precipitation moisture sources. After modification, the estimated annual average fre was increased from 7.5% to 14.8%, well calibrating the existing model. This study highlights the contribution of transpiration vapor to precipitation and provides more information on the formation and evolution of precipitation to better serve future hydro‐climatic research. Plain Language Summary: In the context of global warming, remarkable changes have occurred in the evapotranspiration capacity and precipitation, which inevitably caused a series of alternations to the hydrological and atmospheric cycles. Defining the moisture sources of precipitation and its evolution in the atmosphere is of great significance for further exploration of complex interactions between hydrology and climate change. Recently, increasing studies have emphasized the importance of recycled vapor derived from local evapotranspiration to precipitation. As a sensitive indicator, d‐excess has been widely used to quantify the proportion of recycled vapor in precipitation (or called the recycling ratio). However, existing d‐excess‐based models for determining the recycling ratio ignore to take the transpiration vapor into account, and the calculated ratio tends to be lower than the true value, thus underestimating the important role of recycled vapor in precipitation. In this study, the existing model was modified by considering the contribution of transpiration vapor and applied well in Guyuan, China located in a monsoon marginal zone with complex precipitation moisture sources. This study highlights the importance of the transpiration vapor contribution to local precipitation and provides more information on the formation and evolution of precipitation to better serve future hydro‐climatic research. Key Points: A modified and generic d‐excess‐based model was presented to determine the contribution of recycled moisture to local precipitationThe annual average recycling rate estimated using the modified model was 14.8% in Guyuan, higher than that of 7.5% before modificationTranspiration vapor accounts for an important part for formation of precipitation and significantly influences hydro‐atmospheric cycle [ABSTRACT FROM AUTHOR]

Tibetan Plateau is the headwater region of many major Asian rivers and very susceptive to climate change. Therefore, knowledge about climate and its spatiotemporal variability in this area is very important for ecological conservation, water resource management and social development. The aim of this study was to reconstruct and analyze the hydroclimate variation on eastern Tibetan Plateau (ETP) over many centuries and explore possible forcing factors on regional hydroclimate variability. We used 118 tree-ring chronologies from ETP to reconstruct the gridded May-July Standardized Precipitation Evapotranspiration Index for the ETP over the last millennium. The reconstruction was developed using an ensemble point-by-point reconstruction method, and a searching region method was used to locate the candidate tree-ring chronologies. The reconstructions have nicely captured the spatial and temporal features of the regional drought variation. The drought variations in south and north of 32.5°N are notably different, which may be related to the divergence influence of North Atlantic Oscillation on the climate systems in the south and north, as well as differences in local climate. Spectral analysis and series comparison suggest that the drought variation in the northeastern Tibetan Plateau has been possibly influenced by solar activity on centurial and longer time scale. [ABSTRACT FROM AUTHOR]

ABSTRACT Drought is a recurrent natural disaster in northwestern China and it can have a substantial impact on the affected region; therefore, knowledge of drought variability is very important for drought adaptation and mitigation. However, the observed climate data are generally limited in length, which may hamper our understanding the full range of drought variability. Using tree-ring width measurements of 155 series from 81 Pinus tabulaeformis trees at three sites in the northern Min Mountains of northwestern China, the standardized precipitation evapotranspiration index ( SPEI) for May-August from 1804 to 2011 were reconstructed, which account for 64.8% of the variance in the instrumental record over 1954-2011. The new reconstruction is generally consistent with other moisture reconstructions nearby. Two notable features of the SPEI reconstruction is the severe drought starting in the late 1990s and the gradual drying trend since 1954. These features are also apparent in areas located in the north boundaries of Eastern Asian Summer Monsoon ( EASM), which indicates that the study area may be affected by the EASM. [ABSTRACT FROM AUTHOR]

Knowledge about the spatiotemporal tree growth variability and its associations with climate provides key insights into forest dynamics under future scenarios of climate change. We synthesized 17 tree-ring width chronologies from four tree species at the high-elevation sites in the southeast Tibetan Plateau (SETP) to study the regional tree growth variability and climate-growth relationships. Despite of diverse habitats and different physiological characteristics of these species, these tree-ring chronologies shared a significant common variance in SETP. An unprecedented increase in the shared variance is found along the latter half of the 20th century, coinciding with the enhancement of the frequency of extreme rings among chronologies. It is found that minimum winter temperature tends to be the dominant climate for trees in this region. The site-specific responses in cold (1965–1980) and warm (1990–2005) intervals by means of Fuzzy Cmeans (FCM) clustering reveal that the remarkable enhancement of growth synchrony among trees mainly occur in warm conditions. This is different from previous findings indicating that increased consistence among temperature sensitive tree rings in cold periods. This may be related to the reduced temperature sensitivity of regional tree growth as winter minimum temperature is lower than a certain threshold, which is in agreement with the “principle of ecological amplitude”. In addition, it is worth noting that precipitation in June have started to restrain the tree growth since the beginning of the 1980s, which is possibly an important contributor for synchronized growth among trees in SETP. [ABSTRACT FROM AUTHOR]

Satellites are an effective source of atmospheric carbon dioxide (CO2) monitoring; however, city-scale monitoring of atmospheric CO2 through space-borne observations is still a challenging task due to the trivial change in atmospheric CO2 concentration compared to its natural variability and background concentration. In this study, we attempted to evaluate the potential of space-based observations to monitor atmospheric CO2 changes at the city scale through simple data-driven analyses. We used the column-averaged dry-air mole fraction of CO2 (XCO2) from the Carbon Observatory 2 (OCO-2) and the anthropogenic CO2 emissions provided by the Open-Data Inventory for Anthropogenic Carbon dioxide (ODIAC) product to explain the scenario of CO2 over 120 districts of Pakistan. To study the anthropogenic CO2 through space-borne observations, XCO2 anomalies (MXCO2) were estimated from OCO-2 retrievals within the spatial boundary of each district, and then the overall spatial distribution pattern of the MXCO2 was analyzed with several datasets including the ODIAC emissions, NO2 tropospheric column, fire locations, cropland, nighttime lights and population density. All the datasets showed a similarity in the spatial distribution pattern. The satellite detected higher CO2 concentrations over the cities located along the China–Pakistan Economic Corridor (CPEC) routes. The CPEC is a large-scale trading partnership between Pakistan and China and large-scale development has been carried out along the CPEC routes over the last decade. Furthermore, the cities were ranked based on mean ODIAC emissions and MXCO2 estimates. The satellite-derived estimates showed a good consistency with the ODIAC emissions at higher values; however, deviations between the two datasets were observed at lower values. To further study the relationship of MXCO2 and ODIAC emissions with each other and with some other datasets such as population density and NO2 tropospheric column, statistical analyses were carried out among the datasets. Strong and significant correlations were observed among all the datasets.

Knowledge of natural long-term drought variability is essential for water resource management and planning, especially in arid and sub-arid regions of the world. In the eastern Qilian Mountains of China, long-term drought variability based on high-resolution proxy records such as tree-ring data are still scarce to date. Here we present a new tree-ring chronology from the eastern Qilian Mountains which provides a valuable 1,002-year record (1009-2010 CE) of drought variability. The new reconstruction of June-July 5-month scale standardized precipitation and evapotranspiration index is the first millennium tree-ring estimate of past climate developed in the eastern Qilian Mountains. The record shows that this region has experienced several persistent droughts and pluvials over the past millennium, with significantly drier climate during the fifteenth century and dramatic wetting since the nineteenth century. The low frequency generally agrees with other nearby studies based on both tree-ring data and other proxy data. [ABSTRACT FROM AUTHOR]

Abstract: Tree-line ecotones are strongly climatically limited and serve as potential monitors of climate change. We employed annual growth increment from tree-rings, and tree density and age structure data derived from two Juniperus przewalskii tree-line sites in the eastern part of the Qilian Mountains, northeastern Tibetan Plateau, to detect the responses of tree growth and population dynamics to climate change. High temperature favors tree growth and is associated with increased tree density at tree-line, and an advance in tree-line position. Significantly positive correlations were found between ring-width and mean monthly air temperatures in current and previous June, July and August. Tree recruitment began to increase rapidly at the two sites after the Little Ice Age, but then decreased starting in the 1970s. The number of trees established coincides with temperature changes. The warming trend after the Little Ice Age favors increases of tree density and an advance of tree-line. The majority of trees established during the period of 1931–1970, which coincides well with the rapid radial growth of the trees. [Copyright &y& Elsevier]

The Chinese vegetable production system is characterized by high fertilizer inputs and environmental risks. However, the spatial patterns and mitigation potential of greenhouse gas emissions from the Chinese vegetable production systems are unknown. In this study, greenhouse gas emissions and intensity in the Chinese vegetable production systems were quantified via life cycle assessment. The weighted average greenhouse gas emissions and intensity for Chinese vegetable production were 6,244 kg CO 2 -eq ha−1 and 116 kg CO 2 -eq t−1, respectively. The total greenhouse gas emissions were 139 Mt CO 2 -eq. N fertilizer was the largest contributor, accounting for 78.2 % of greenhouse gas emissions. Large variations in greenhouse gas emissions and intensity were detected among the regions as well as cultivation methods. Greenhouse gas emissions in the North region were 9.7–30.0 % greater than those in the South region due to 18.2–58.2 % higher N fertilizer rate in the North region. Greenhouse gas emissions from greenhouse vegetable production were 55.4–84.1 % greater than those from open-field vegetable production because the former had 13.0–51.3 % higher N fertilizer rate and more material structure input. Greenhouse gas intensity for greenhouse vegetable production was 39.6 % higher than that for open-field vegetable production in the North region. In contrast, greenhouse gas intensity was similar for both greenhouse and open-field vegetable production in the South region. The mitigation potential for greenhouse gas emissions on a per-hectare basis was higher for the North region than that for the South region, which was attributed to a relatively greater N fertilizer reduction potential in the North region. Optimizing the N rate could reduce the total greenhouse gas emissions from the Chinese vegetable production systems by 16.7 %. This work could enable researchers and policymakers to reduce the contribution of vegetable production to global climate change. [Display omitted] • The average GHG emission from Chinese vegetable production was 6,244 kg CO 2 -eq ha−1. • The North region had 9.7–30.0 % higher GHG emission than the South region. • The greenhouse system had 55.4–84.1 % higher GHG emission than the open-field system. • The North region had greater GHG mitigation potential than the South region. • Optimizing the N fertilizer rate could reduce the total GHG emission by 16.7 %. [ABSTRACT FROM AUTHOR]

• Soil N availability increased at alpine treeline ecotones. • Plant N and P stoichiometry indicates nutrient patterns at alpine treeline ecotones. • Soil N pools drive plant growth and might have a strong effect on treeline dynamics. • Alpine treeline might respond quickly to available nutrients change with global warming. Alpine treeline ecotone is one of the most vulnerable ecosystems and considered an ideal "warning line" for the monitoring of global climate change. However, shifts in the nutrient traits of plant biomass and soils of alpine treeline ecotones along the elevation gradient are poorly investigated. This study aimed to quantify nitrogen (N) and phosphorus (P) traits of Qinghai spruce (Picea crassifolia) and their driving factors for seven typical treelines (timberline - treeline - tree species line) covering 800 km southeast-to-northwest transect within the northeastern Tibetan Plateau. The biomass of plant tissue (leaves, twigs, and fine roots) and the N and P contents in them and soil nutrients (total and available N and P) were determined. Two mechanisms, which can drive the nutrient content in plants, namely, temperature-plant physiology and the sink (growth) limitation hypotheses were checked here. The N and P contents in plant tissue increased with the elevation, and temperature negatively impacted tissue N and N:P in all of the seven typical treelines, which supported both of the hypotheses. Soil N availability increased along the altitudinal gradient in 1.23 times. Soil TN explained 13.4% (p < 0.01), NO 3 –-N 10.1% (p < 0.05), and NH 4 +-N 8.6% (p < 0.05) of the variations in plant tissue N and P stoichiometry and biomass. Thus, soil N pools stimulated Qinghai spruce growth and have a strong effect on treeline dynamics. [ABSTRACT FROM AUTHOR]

Key message: Late-season extreme climatic events induced variations in wood density and extended growth for more than a month in 2016 inJuniperus przewalskiiKom. growing on the Northeastern Tibetan Plateau, suggesting extraordinary growth resilience of the species in response to short extreme events over the cold and arid region. Context: Monitoring xylem formation (xylogenesis) during extreme meteorological events helps assessing climate change impacts on tree growth. Aims: For better insight into tree-growth responses, here we compare the intra-annual formation of annual ring with and without intra-annual density fluctuation in J. przewalskii in a cold and arid environment on the Northeastern Tibetan Plateau. Methods: Cambial phenology and xylogenesis observations of five mature trees during the 2016 intra-annual density fluctuation growth ring and the five-preceding year (2011–2015) were used for comparison. The frequency of population level occurrence of intra-annual density fluctuation in 2016 was examined on additional 50 randomly selected trees. Results: The return of precipitation in conjunction with warm temperatures after summer drought promoted the growth resumption in 64% of our study trees, resulting in the observed intra-annual density fluctuation. These trees experienced a growing season 1 month longer than trees without intra-annual density fluctuation. The extended growth period resulted in a 17% increase in stem biomass in trees that experienced intra-annual density fluctuation. Conclusion: Our results highlight the extraordinary resilience of J. przewalskii trees in response to extreme climatic events in the cold and dry conditions of the Tibetan Plateau. [ABSTRACT FROM AUTHOR]

Hydroclimate variations inferred from proxies, such as tree rings, provide a long‐term context for the understanding of the current climate change. In humid Southeastern China (SEC), relatively limited long‐term tree‐ring records were published due to the paucity of old trees. This study develops a robust tree‐ring width chronology from the Chinese cedar (Cryptomeria fortune) Fengshui woods, spanning from 1781 to 2015, by far the longest in SEC. Common growth anomalies of the Fengshui trees can well capture long‐term springtime (March–May) Standardized Precipitation Evapotranspiration Index (SPEI) changes over the past 230 years in SEC. This hydroclimate‐sensitive chronology shows significant correlations with El Niño‐Southern Oscillation (ENSO) like sea surface temperature modes, indicating that ENSO may act as an important regulator in local springtime SPEI. However, interdecadal shifts in the relationships between the variances of tree rings and ENSO reveal that the ENSO‐SPEI teleconnection over SEC was an unstable process, and it collapsed during the periods of 1820s–1860s and 1920s–1960s, when ENSO was in its decaying phases. Key Points: A robust tree‐ring width chronology is developed based on Chinese cedar Fengshui woods, by far the longest for Southeast ChinaENSO acts as a major regulator in local springtime hydroclimate, however, the teleconnection between them is dynamic through timeA conspicuous dipole hydroclimate pattern between Southeast and North China is modulated by PDO during the historical periods [ABSTRACT FROM AUTHOR]

• Cambial phenology and xylogenesis of trees were monitored over six years. • Warming advanced and lengthened the growing season. • Growth onset advanced 3.1 days decade−1 while growth end advanced 1.8 days decade−1. • A longer growing season did not result in a greater wood production. • Early summer drought reduced growth rate and wood production. Studies of xylogenesis can provide mechanistic understandings of the influence of climate on wood production and carbon sequestration at the cellular level. It is not yet clear how trees will respond to increasing temperature and precipitation variability and other extreme meteorological events that are expected to occur as climate continues to change. Here, we analyzed cambial phenology and xylogenesis of Juniperus przewalskii Kom. weekly (2011–2014) or biweekly (2015–2016) over six years on the northeastern Tibetan Plateau. We found that temperature plays a decisive role in the onset of xylogenesis and a daily mean temperature of 6.1 °C appears to be the threshold that determines growth onset. Additionally, we observed the end of xylogenesis is related to summer drought conditions. During the course of our observations, the onset of xylogenesis advanced nearly twice as much as the end of xylogenesis (3.1 vs 1.8 days decade−1, respectively), indicating a slight lengthening of the growing season. However, an increase in the duration of the growing season did not necessarily result in a greater level of wood production. In fact, we found that water availability affects the growth rate and early summer precipitation appears to be a key factor of wood production over the northeastern Tibetan Plateau. Our study provides new evidence of the malleable nature of tree growth and reveals potential mechanisms of how tree growth adjusts to climatic variations in cold and arid region. [ABSTRACT FROM AUTHOR]