三峡消落带优势植物狗牙根在水库落干期的叶性状变化  

Intra-annual variations in leaf traits of Cynodon dactylon(L.)Pers.during exposure period in riparian zone of Three Gorges Reservoir Area

作　　者：张爱英 樊大勇[2] 马良[3] 杨丹 熊高明 谢宗强[2] Zhang Ai-Ying;Fan Da-Yong;Ma Liang;Yang Dan;Xiong Gao-Ming;Xie Zong-Qiang(China Jiliang University,Hangzhou 310018,China;State Key Laboratory of Vegetation and Environmental Change,Institute of Botany,Chinese Academy of Sciences,Beijing 100093,China;Shaanxi Mineral Resources and Geological Survey,Xi’an 710068,China;College of Life Sciences,Guizhou University,Guiyang 550025,China)

机构地区：[1]中国计量大学,杭州310018 [2]中国科学院植物研究所,植被与环境变化国家重点实验室,北京100093 [3]陕西省矿产地质调查中心,西安710068 [4]贵州大学生命科学学院,贵阳550025

出　　处：《植物科学学报》2022年第4期453-461,共9页Plant Science Journal

基　　金：国家自然科学基金(31901211);浙江省自然科学基金探索项目(LY21C030006);中国科学院知识创新工程项目(KZCX2-XB3-09)。

摘　　要：为研究三峡消落带植物叶片功能性状在落干期的变化,于2014年6月和8月,在湿-干-湿循环的落干阶段,分别在176、170、164、158 m(不同淹水强度)调查消落带优势草本植物狗牙根(Cynodon dactylon(L.)Pers)的8个叶片功能性状,包括:最大净光合速率(A _(area)、A _(mass))、比叶面积(SLA)、气孔导度(G _(s))、叶片氮含量(N _(area)、N _(mass))、叶片磷含量(P _(area)、P _(mass))。结果显示:(1)生长时长(6月和8月)对A _(area)、A _(mass)、G _(s)、SLA和P _(mass)的变异性贡献率与淹水强度相近甚至高于后者,而生长时长对N _(area)、N _(mass)和P _(area)变异性的贡献率较低;(2)在8个性状的两两耦合关系中,有5对(A _(area) vs.G _(s),A _(mass) vs.G _(s),SLA vs.G _(s),A _(area) vs.N _(area),P _(mass) vs.N _(mass))受到了生长时长的显著影响;(3)A _(mass)、N _(mass)和P _(mass)在各淹水强度之间无明显变化规律。无论在6月还是8月,158 m的A _(area)均大于未淹水的176 m;消落带的SLA显著小于未淹水对照带;N _(area)的大小依次为:158 m>164 m>176 m>170 m;P _(area)均表现出消落带高于对照带。研究结果表明,在三峡水库消落带,年内生长时长差异会导致狗牙根的光合能力、比叶面积等多个性状发生显著变化,且对功能性状间的耦合关系影响显著;较少受到生长时长影响的稳定性状N _(area)和P _(area)可能更具群落与环境梯度之间关系的指示作用。To study intra-annual variations in leaf traits of long-term submerged plants in the riparian zone of the Three Gorges Reservoir Area(TGA)during the dry period of the flood-dry-flood cycle,we investigated eight leaf functional traits(maximum net photosynthesis rate(A _(area),A_(mass)),stomatal conductance(G_(s)),specific leaf area(SLA),leaf nitrogen concentration(N_(area),N_(mass)),and leaf phosphorus concentration(P_(area),P_(mass)))of Cynodon dactylon(L.)Pers.at four elevations(176,170,164,and 158 m)in June and August 2014.Results showed that:(1)Exposed period significantly contributed to variations in A_(area),A_(mass),G_(s),SLA,and P_(mass)(more than 26%of total variation),similar to or even higher than submergence intensity.However,exposed days contributed little to variations in N_(area),N_(mass),and P_(area)(less than 15%).(2)Five bivariate relationships between leaf traits(A_(area) vs.G_(s),A_(mass) vs.G_(s),SLA vs.G_(s),A_(area) vs.N _(area),P_(mass) vs.N_(mass))showed significant changes between two exposed periods.The intercept of A_(mass) vs.G_(s) changed significantly between June and August.(3)A_(mass),N_(mass),and P_(mass) showed no obvious trends in submergence intensity between June and August;A_(area) was significantly higher at 158 m than at 176 m regardless of month;SLA and P_(area) were significantly lower in the riparian zone(170,164,and 158 m)than at 176 m;variation in N_(area) was in the order:158 m>164 m>176 m>170 m.These results suggest that annual exposed period can lead to significant variations in C.dactylon leaf traits,as well as the relationships between them.As N_(area) and P_(area) were stable traits(less affected by exposed days and submergence intensity),they may be candidate predictors for the structure and function of the TGA riparian ecosystem.

关 键 词：淹水强度 生长时长 功能性状 最大净光合速率 耦合关系 SMA分析 

分 类 号：Q948[生物学—植物学]