水位波动的幅度与频率对刺苦草(Vallisneria spinulosa)生物量和形态特征的影响  

Impact of water level fluctuations with different amplitudes and frequencies on biomass and morphological traits of Vallisneria spinulosa

作　　者：丁明明 黎磊 金斌松 陈家宽 Ding Mingming;Li Lei;Jin Binsong;Chen Jiakuan(Jiangxi Province Key Laboratory of Watershed Ecosystem Change and Biodiversity,Center for Watershed Ecology,Institute of Life Science and School of Life Sciences,Nanchang University,Nanchang 330031,P.R.China;Jiangxi Poyang Lake Wetland Conservation and Restoration National Permanent Scientific Research Base,National Ecosystem Research Station of Jiangxi Poyang Lake Wetland,Nanchang University,Nanchang 330031,P.R.China;The Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering,Institute of Biodiversity Science,Fudan University,Shanghai 200438,P.R.China)

机构地区：[1]江西省流域生态演变与生物多样性重点实验室,南昌大学生命科学研究院流域生态学研究所,南昌大学生命科学学院,南昌330031 [2]江西鄱阳湖湿地保护与恢复国家长期科研基地,江西鄱阳湖湿地生态系统定位观测研究站,南昌330031 [3]复旦大学生物多样性科学研究所,生物多样性与生态工程教育部重点实验室,上海200438

出　　处：《湖泊科学》2021年第1期192-203,共12页Journal of Lake Sciences

基　　金：国家重点研发计划项目(2018YFD0900904);国家自然科学基金项目(31400403,31960248);江西省自然科学基金项目(20192BAB204006)联合资助.

摘　　要：沉水植物是维持浅水湖泊清水稳态以及湖泊生态系统结构与功能的关键生物类群.近年来,气候变化和人类活动的双重作用造成湖泊水文情势的明显改变,对沉水植物的生长、繁殖和演替有着较大的影响.本文选取2个水位波动幅度与2个波动频率(逐渐改变水位),以恒定水位作为对照,研究湿地中具有重要生态功能的沉水植物刺苦草(Vallisneria spinulosa)的生物量及地上和地下营养器官形态结构对水位波动的响应.结果表明,相对于恒定水位,波动水位(低幅度低频率、低幅度高频率、高幅度低频率、高幅度高频率)对刺苦草的总生物量和获取限制资源相关器官有显著影响.相比于对照组,水位波动能够显著降低刺苦草分株数、叶片数、根数、根长、匍匐茎数、总匍匐茎长以及叶、根、地上和地下生物量,但会显著增加其株高和比叶面积.不同波动频率(低频率和高频率)和幅度(低幅度和高幅度)对光合器官的形态特征都没有显著影响,但叶和地上部分的生物量积累均受到波动幅度的显著影响.水位波动幅度显著改变了刺苦草的根数和根长,而波动频率的影响不显著.因此,对浅水湖泊受损刺苦草群落进行重建时,应避免较大幅度的水位波动,从而有利于增强植株快速恢复的能力.Submerged macrophytes are key biological components in maintaining the clear water state of shallow lakes and structure and function of lake ecosystems.In recent years,the ongoing climate change and increasing human activities have led to prominent changes in the hydrological regime of lakes,having major influences on growth,reproduction,and succession of submerged macrophyte species.In this study,we set up two water level fluctuation amplitudes and two fluctuation frequencies,with constant water level as a control,to explore the responses of biomass and above-and belowground morphological traits of the submerged macrophyte Vallisneria spinulosa to water level fluctuations.Our results showed that compared with the constant water level,fluctuating water level treatments(small amplitude and low frequency,small amplitude and high frequency,large amplitude and low frequency,and large amplitude and high frequency)had a significant effect on total biomass and the resource-harvesting structures of V.spinulosa.Compared with the control,water level fluctuations significantly decreased the number of ramets,leaves and roots,length of roots,number and total length of stolons,as well as leaf,root,above-and belowground biomass.However,water level fluctuations obviously enhanced plant height and specific leaf area.Both frequency(low and high)and amplitude(small and large)of water level fluctuations had no significant effect on morphology of aboveground photosynthetic organs,but the biomass accumulation of leaves and the aboveground part were significantly affected by the amplitude of water level fluctuations.Furthermore,both the number and length of roots were affected by amplitudes but not by frequencies of water level fluctuations.Therefore,it is necessary to avoid large range of water level fluctuations during the V.spinulosa community reestablishment in shallow lakes,in order to enhance the recovery ability of submerged macrophytes.

关 键 词：水位 波动幅度 波动频率 形态响应 营养生长 沉水植物 刺苦草 

分 类 号：Q948[生物学—植物学]