文献类型：期刊文献

中文题名：极端干旱条件下亚热带杉木人工混交林林木受损特征及影响因素

英文题名：Damaged Characteristics and Influencing Factors of Cunninghamia lanceolata Mixed Plantations in Subtropics under Extreme Drought Conditions

作者：王旭[1,2] 郭昊[1,2,3] 宝音满达[1,2] 周光益[1,2] 陈跃华[4] 李党仁[4]

第一作者：王旭

机构：[1]中国林业科学研究院热带林业研究所,广州510520;[2]南岭北江源国家森林生态系统观测站,广州510520;[3]海南大学,海口570100;[4]湖南省临武县西山国有林场,临武424300

年份：2025

卷号：61

期号：5

起止页码：12-22

中文期刊名：林业科学

外文期刊名：Scientia Silvae Sinicae

收录：;EI(收录号：20252218511887);北大核心:【北大核心2023】；

基金：南岭北江源森林生态系统国家定位观测研究站建设项目(林规批字〔2023〕10号)。

语种：中文

中文关键词：降水格局;林分结构;土壤物理性质;林木受损;混交林

外文关键词：precipitation pattern;stand structure;soil physical properties;damage to trees;mixed forest

分类号：Q958.15;S154.5;S718.5

摘要：【目的】探索南方人工林林分中更易受到干旱的影响的类型,以及干旱导致树木受损或死亡的关键影响因子,以期为全球变化背景亚热带森林经营管理提供理论支撑。【方法】以2022年发生在我国南方地区极端干旱为契机,以林龄相近的杉木-闽楠为主的人工混交林为研究对象,按陡坡缓坡2种坡度、2种树种混交与3种以上树种混交4个类型,分别设置3块植物样地,调查样地内物种组成、胸径、树高、单木受损率以及土壤物理性等,分析本次极端干旱气候特征、不同坡度林分受损率、受损木组成及影响因素等。【结果】坡度对土壤团聚体影响较大,而混交类型对土壤团聚体无影响,混交类型对表层(0~20 cm)土壤孔隙度、土壤密度、最大持水量、毛管持水量和最小持水量均产生较大的影响,且随着土层深度的增加影响减少,相同混交类型中,不同坡度对这些指标无显著的影响;干旱导致树木不同程度的损伤,平均受损率为29.18%,其中轻度受损、中度受损和重度受损分别为15.46%、2.42%和11.3%;受损木中主要为林冠层优势种和林下更新层受损严重,其中阔叶树比针叶树受损严重,人工栽培种比天然更新种受损严重;坡度和坡位对树木受损率影响最大,此外还受林分密度、土壤密度、土壤团聚体、海拔、20 cm土层总孔隙度、土壤最大持水量和毛管持水量等因素影响。【结论】2022年南方极端干旱呈降水格局显著变化的特征,该变化与全球气候变化的预测具有一致性,多树种混交有利于提高森林的抗旱能力,坡和上坡位易受干旱的影响,干旱对森林的影响是多因素相互作用的结果。亚热带森林经营管理应以构建多树种混交林为主,确定合理的林分密度,加强表层土壤管理。
【Objective】Global climate change has altered precipitation patterns,and tree mortality caused by drought is a magnitude threat to global forest ecosystems.The impact of severe seasonal drought on Cunninghamia lanceolata plantations in southern China has become a hot topic in ecological research.However,the investigation into the damage characteristics and influencing factors of extreme drought on subtropical Chinese fir mixed forests remains limited.This article aims to explore which types of forest stands are more susceptible to the impact of drought,the key influencing factors of tree damage or death caused by drought,in order to provide theoretical support for subtropical forest management in the context of global change.【Method】An extreme drought event occurred in southern China in 2022,with the opportunity,this study targeted at mixed plantations of C.lanceolata and Phoebe bournei with similar age.Three plant plots were set up in each of two types of slopes of steep slope and gentle slope,and two types of mixed patterns of mixed plantations with two tree species and mixed plantations with three or more than three tree species.The species composition,diameter at breast height(DBH),tree height,damage rate of individual trees and soil physical properties in the plots were investigated,the characteristics of the extreme drought climate occurred in southern China in 2022,the stand damage rate at various slopes,the composition of damaged trees,and the influencing factors were analyzed.【Result】Slope had a greater effect on soil aggregates,while the mixed type of plantations had no effect on soil aggregates.The mixed type had a significant effect on surface(0–20 cm)soil porosity,soil bulk density,maximum water holding capacity,capillary water holding capacity and minimum water holding capacity,and the effect decreased with the increase of soil depth.Different slopes had no significant effect on above these indexes.The drought resulted in varying degrees of damage to trees,with an average damage rate of 29.18%.Among them,mild damage accounted for 15.46%,moderate damage for 2.42%,and severe damage for 11.3%.The severely damaged trees mainly consisted of dominant species in the canopy and understory regeneration layers,with broadleaf trees being more severely impacted than coniferous trees,and planted species more affected than natural regenerating species.Slope gradient and position had the greatest impact on tree damage rates,along with factors such as stand density,soil bulk density,soil aggregate stability index(SASI),elevation,total porosity of the 20 cm soil layer,maximum water holding capacity of soil,and capillary water holding capacity.【Conclusion】The extreme drought occurred in southern China in 2022 has demonstrated the characteristics of altered precipitation patterns under global climate change.The mixed plantations with multiple advantageous species are beneficial for improving the drought resistance of forests.Steep slopes and uphill areas are more susceptible to drought,and the impact of drought on forests is the result of multiple factors interacting.In future management of subtropical forests,priority should be given to constructing mixed forests with multiple tree species,determining reasonable stand density,and strengthening surface soil management.