中图分类号：S791.247 文献标识码：A DOI：10.7525/j.issn.1006-8023.2025.04.004

Abstract：As the global climate warms，the frequency of extreme events increases，resulting in the decline and even death of some of the world's forests，and insome places theimpactis more pronouncedon large trees.The climate in Northeast China is graduall becoming warmer and drier，and Pinus koraiensis，asthe main precious tree species in Northeast China，has alreadyexperiencedadeclinein the studyarea.However，thediferences inthe effctsof temperatureriseand extreme events onthe growth of Pinus horaiensis ofdiferent diameter classs have not been studied in detail.Theresponseofdiferentdiameterclasssof Pinus horaiensis toclimatechangeandtheadaptabilitycharacteristics （resistance，resilience，restoring elasticityand relative resilience to extreme drought were analyzed and compared by dendrochronology inthe natural forest areaof southern Xiaoxing'anling.Theresults showed as folows：1）There was a negativecorrelation betweenlarge diameter and the maximum temperature at the begining of the growing season，and a positive correlationbetweenlargediameterandtheprecipitation in Juneof thesame year；the minor grade was negatively correlatedwiththe precipitationat theendofthegrowing seasoninthecurrentyearandthepreviousyear.2）The growth trendof large diameter class and small diameter classwas basicallythesame，inwhich theresponsestabilityoflargediameter classtothe maximum temperature of the growing season was lower than thatof small diameter class，and the growthofsmall diameterclasswas mainlyafected bythedecreaseof precipitation.3）Withthewarmingofclimate，the resistanceand relativeresilienceof diffrent diameter classs to extremedrought showedadownward trend，and the adaptabilityoflarge diameterclasstodrought was slightlylower thanthatofsmalldiameterclass，butthedifference was notobvious.The diffrenceof response to climate and the stabilityof responseof different diameterclasses of Pinus horaiensis mainlyappearedintheearlygrowingseasonofrapid growth，reflectingthediferentdemandofdifferentdiameter classes forhydrothermalconditions.Withthewarmingof climate，theadaptabilityofradial growthofdiferentdiameter classes of Pinus horaiensis to extremedrought events decreased，and itcouldnotrecover tothe pre-droughtlevel in the shortterm.Itispredicted thatthefutureclimatewillcontinuetorise，andtheadaptabilityoflargediameterclass Pinus koraiensis may weaken.Further analysis shouldbecarried out basedonthefrequencyand time of drought，and the research cope shouldbe expanded todeal withthe adverse efects of warmingon Pinus horaiensis forest，which will play animportant role in forest management.

Keywords： Tree ring；diameter grade；restoring elasticity；drought； climate warming; Pinus koraiensis

0 引言

全球气候变暖，伴随着干旱频率和强度的增加[1]，导致森林普遍减少和树木死亡[2-3]，严重影响了人类活动和生态系统的稳定性。树木死亡率可能会随着气候变化而增加，其频率和影响范围也会增加[4-6]。通常大径级的树在森林中起着关键作用，大径级树木比小径级树木对干旱的反应更敏感，研究结果表明，对干旱胁迫的脆弱性是随着树高增加而增加[7]。由于干旱等原因引起的森林衰退现象已经在世界各地发生，预计未来会随着气候变化而增多，并且对生态系统固碳能力产生负面作用。所以，了解不同径级树木应对干旱事件的反应能力以及对气候变化的响应稳定性变得尤为重要。

通常认为树木与气候之间的关系是稳定的[8]，但是随着研究的不断深人，发现一些树木对气候响应会随着某些气候因子变化而变化[9-10]。研究证实树木在北半球中高纬度寒冷且暖干化严重的地区会出现与气候响应不稳定的现象[11-13]，且多发生在对土壤水分要求较高的浅根性树种，也有可能发生在干旱区的深根性树种，比如青海云杉（Piceacrassifolia）[14]、冷杉（Abiesfabri）[15]和红松[13]等。除了变暖可能改变树木生长气候响应特征以外，一些极端事件对于树木生长的影响更加明显，而且变暖可能导致树木生长对于极端事件的适应性降低。研究表明[16-19]，树种、径级、年龄、竞争、纬度和海拔等生物和非生物因素会影响干旱对树木的影响。一般认为，当树木经历了长期的干旱胁迫并到达一个阈值，将无法恢复到干旱发生前的状态，最后导致树木大面积的衰退或死亡[20-21]。……