摘要
鹅绒委陵菜(Potentilla anserina)是高寒草甸的广布种和典型的杂类草,随生境变化其无性繁殖能力、空间拓展性、形态可塑性等差异显著。为探明该种在不同高寒生境下的光合特性及其与环境因子的关系,同时寻找影响其繁殖拓展能力的主要环境诱因,在若尔盖高原选择沼泽湿地、湿草甸和干草甸三类样地对鹅绒委陵菜的光合日变化进行比较。结果表明:7月下旬,由于光辐射强、大气温度高,各生境中鹅绒委陵菜的叶片净光合速率(P_n)、蒸腾速率(T_r)、瞬时水分利用效率(IWUE)和光能利用效率(LUE)均显著高于8月下旬(P<0.05);同一月份,干草甸环境下的P_n显著高于湿草甸和沼泽湿地(P<0.05);相关性分析显示,各环境中光合有效辐射(PAR)与P_n均呈显著正相关(P<0.05),干草甸环境下空气相对湿度(RH)、土壤质量含水量(SWC)与P_n亦呈显著正相关关系(P<0.05);从沼泽湿地、湿草甸到干草甸,鹅绒委陵菜的净光合速率和水分利用效率增大;光补偿点(LCP)降低,光饱和点(LSP)升高,光合作用时间延长;表观量子效率(AQY)和羧化效率(CE)提高。这表明,在相对干旱的生境下,鹅绒委陵菜的光合能力得到增强,各光合生理参数朝着有利于其生长的方向发展。水分条件可能是影响鹅绒委陵菜繁殖能力和盖度的重要环境因子。
Potentilla anserina is a cosmopolitan species and miscellaneous forb in alpine meadow,whose asexual reproduction,space expansibility,and morphological plasticity vary significantly with different habitats. The main aims of this study were to ascertain the photosynthetic characteristics of P. anserine under different alpine conditions and their relationship with the environmental factors,and thus find the main environmental factors influencing their propagation ability. Three types of ecosystems（ swamp,wet meadow and dry meadow） were selected in the Zoige Plateau to compare the diurnal changes of photosynthesis in P. anserine. The results showed that the average values of net photosynthetic rate（ Pn）,transpiration rate（ Tr）,instantaneous water use efficiency（ IWUE） and light use efficiency（ LUE） of P. anserine in different habitats in late July were significantly higher than those in late August（ P〈0.05） due to the stronger radiation and higher atmospheric temperature. In each month,the daily average of Pnof dry meadow was significantly higher than that of wet meadow and swamp（ P〈0.05）. The photosynthetically active radiation（ PAR） was significantly positively correlated with Pnin three habitats（ P 0. 05）. In dry meadow,air relative humidity（ RH） and soil water content（ SWC） also had a significantly positive correlation with Pn（ P〈0.05）. From swamp to wet meadow to dry meadow,Pn,WUE,light saturation point（ LSP）,photosynthetic time,apparent quantum yield（ AQY） and carboxylation efficiency（ CE） of P. anserine gradually increased and the light compensation point（ LCP）decreased. The variations of all parameters indicated that the photosynthetic capacity of P. anserine was enhanced in relatively dry habitats,and its photosynthetic characteristics were moving in the favorable direction for its growth. Water availability may be an important environmental factor that affects the reproduction ability and coverage of P. anserina.
作者
侍瑞
苏培玺
周紫鹃
解婷婷
SHI Rui;SU Pei-xi;ZHOU Zi-juan;XIE Ting-ting(Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China)
出处
《生态学杂志》
CAS
CSCD
北大核心
2018年第7期1943-1951,共9页
Chinese Journal of Ecology
基金
国家重大科学研究计划课题(2013CB956604)
国家自然科学基金青年科学基金项目(41701106)资助
作者简介
通讯作者 侍瑞，女，1986年生，博士研究生，研究方向为生态过程与气候变化。E-mail：18634936969@163．com
