Sex-specific strategies of resource utilization and determining mechanisms of Hippophae rhamnoides in response to community succession  

中国沙棘响应群落演替性别特异的资源利用策略及决定机制

作　　者：Baoli Fan Pengfei Gao Tingting Tian Nana Ding Yongkuan Wan Xianhui Zhou 

机构地区：[1]College of Life Science,Northwest Normal University,Lanzhou 730000,China [2]Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education,Lanzhou 730000,China [3]College of Ecology,Lanzhou University,Lanzhou 730000,China

出　　处：《Journal of Plant Ecology》2024年第4期114-130,共17页植物生态学报（英文版）

基　　金：supported by National Natural Science Foundation of China(32201525);the Gansu province’s Key Research and Development Plan(21YF5NA069);the Longyuan Talent Youth Innovation and Entrepreneurship Team project;the Key Laboratory of Eco-functional Polymer Materials of the Ministry of Education(YDZX20216200001007);the Foreign Expert Introduction Special Project of Gansu Province(22JR10KA010).

摘　　要：The dioecious plant,Hippophae rhamnoides,is a pioneer species in community succession on the Qinghai-Tibet Plateau(QTP),plays great roles in various ecosystem services.However,the males and females of the species differ both in their morphology and physiology,resulting in a change in the ratio of male to female plants depending on the environment.To further explore the functional traits critical to this sex-based distinctive response in the alpine grassland,we have surveyed the sex ratios,measured their photosynthetic parameters,height,leaf area and biomass allocation.The results showed that(i)The males had higher Pn,light saturation point,apparent quantum efficiency,A_(max) and lower water-use efficiency(WUE),which exhibited higher utilization efficiency or tolerance to strong light,while the females indicated higher utilization efficiency for low light and water.And it showed sex-specific biomass allocation patterns.(ii)H.rhamnoides populations across the successional stages all showed a male-biased sexual allocation,which was closely related to sex-specific WUE,Pn,root biomass/total biomass and root-crown ratio.(iii)The leaf traits of H.rhamnoides changed from higher N_(area),P_(area) and leaf mass per area in the early and late to lower in the middle,which meant they moved their growth strategy from resource rapid acquisition to conservation as the succession progressed.(iv)The increasing soil total phosphorus mostly contributed to regulating the sex bias of populations and variations of traits during the succession.The results are vital for the management of grassland degradation and restoration due to shrub encroachment on the QTP.雌雄异株的中国沙棘(Hippophae rhamnoides)作为青藏高原群落演替的先锋物种,在多种生态系统服务功能方面发挥着极为重要的作用。然而,由于中国沙棘雌、雄株在形态和生理上的性别差异,导致雌、雄株的比例随环境变化发生了显著变化。为进一步探究引起高寒草地中国沙棘种群性比偏倚特异性响应的关键功能性状,我们对其种群性比,以及可能影响性比变化的光合特征、高度、叶面积和生物量分配等进行测定。结果表明:(i)中国沙棘雄株具有较高的Pn、LSP、AQE、A_(max)和较低的WUE,雄株对强光具有较高的利用效率或耐受性,而雌株对弱光和水分的利用效率较高,同时种群的生物量分配格局亦具有性别特异性。(ii)不同演替阶段中国沙棘种群均呈现出偏雄的性分配,这与性别特异的WUE、Pn、RB/TB以及R/S密切相关。(iii)随着演替的进行,中国沙棘的叶性状由初期较高的N_(area)、P_(area)以及LMA转变为中末期较低的N_(area)、P_(area)以及LMA,其生长策略由资源快速获取型向保守型转变。(iv)STP的增加能够最大程度调节演替过程中中国沙棘种群性比的偏倚和性状的变异。以上研究结果对青藏高原灌木扩张导致的草地退化和恢复管理具有重要意义。

关 键 词：DIOECIOUS sex ratio shrub encroachment functional traits physiological and ecological strategies 

分 类 号：Q948[生物学—植物学]