摘要
为揭示全球变暖和降水格局改变对我国中亚热带地区森林生态系统地下生态过程的影响,在福建三明森林生态系统国家野外科学观测研究站内开展杉木(Cunninghamia lanceolata)幼树土壤增温和隔离降水双因子试验,研究增温和隔离降水在夏季对杉木幼树细根生物量、形态及养分特征的影响。结果表明,增温(+5℃,W)、隔离降水(-50%,P)和增温+隔离降水(WP)处理的细根总生物量分别比对照(CT)显著降低35.7%、51.7%和59.1%,P和WP处理的细根总生物量分别比W处理显著降低24.9%和36.4%;W、P和WP处理的0~1 mm细根比根长(specific root length,SRL)比对照均显著增加,而0~1和1~2 mm细根比表面积(specific root area,SRA)均无显著变化;与对照相比,W处理的细根N含量、C/N和δ^(15)N均无显著变化,P处理的细根N含量和C/N分别显著增加和下降,WP处理的细根N含量和δ^(15)N显著增加,而C/N显著降低。因此,未来在全球变暖和降水减少的双重环境胁迫下,调整表层细根形态特征可能不是杉木幼树的主要应对策略;而相较于温度升高,降水减少可能是影响杉木幼树细根生物量及表层化学元素分配的主要环境因子。
In order to reveal the effects of global warming and changes in precipitation pattern on the below-ground ecological processes of forest ecosystems in the mid-subtropical regions of China,two-factor test of soil warming and isolating precipitation on Cunninghamia lanceolata was conducted at the National Field Station of Forest Ecosystems and Global Change in Sanming,Fujian Province.The results showed that compared with control(CT),the total fine root biomass of C.lanceolata saplings treated with warming(ambient+5℃,W),precipitation exclusion(ambient-50%,P)and W+P(WP)were significantly reduced by 35.7%,51.7%,and 59.1%,respectively;the total fine root biomass treated with P and WP was significantly reduced by 24.9%and 36.4%compared with W treatment.W,P and WP increased specific root length(SRL)of 0-1 mm fine roots,while the specific root area(SRA)of 0-1 and 1-2 mm fine root had no significant changes.Compared with the CT,W had no effect on fine root N content,C/N andδ^(15)N;P increased fine root N content and decreased fine root C/N;WP increased fine root N content,δ^(15)N,and decreased fine root C/N.Therefore,adjusting the morphological characteristics of surface fine roots might not be the main strategy for C.lanceolata saplings under the dual environmental stress of global warming and precipitation reduction in the future.Compared with the increase of temperature,the precipitation reduction might be the main environmental factor affecting the fine root biomass and surface chemical element distribution of C.lanceolata saplings.
作者
吴帆
熊德成
周嘉聪
魏智华
郑蔚
张丽
杨智杰
WU Fan;XIONG Decheng;ZHOU Jiacong;WEI Zhihua;ZHENG Wei;ZHANG Li;YANG Zhijie(Fujian Provincial Key Laboratory for Plant Eco-physiology,School of Geographical Sciences,Fujian Normal University,Fuzhou 350007,China;FujianSanming Forest Ecosystem National Observation and Research Station,Sanming 365000,Fujian,China)
出处
《热带亚热带植物学报》
CAS
CSCD
北大核心
2022年第4期509-517,共9页
Journal of Tropical and Subtropical Botany
基金
国家自然科学基金项目(32071743,31930071)
国家重点基础研究计划(2014CB954003)资助。
关键词
土壤增温
隔离降水
细根生物量
养分
氮同位素
Soil warming
Precipitation exclusion
Fine-root biomass
Nutrient
Nitrogen isotope
