氮水添加对黑沙蒿种子功能性状的影响  

Effects of nitrogen and water addition on seed functional traits of Artemisia ordosica

作　　者：马斌 佘维维[1,3] 秦欢 宣瑞智 宋春阳 袁新月 苗春 刘靓 冯薇[1,3] 秦树高[1,4] 张宇清[1,2,3,5] MA Bin;SHE Wei-Wei;QIN Huan;XUAN Rui-Zhi;SONG Chun-Yang;YUAN Xin-Yue;MIAO Chun;LIU Liang;FENG Wei;QIN Shu-Gao;ZHANG Yu-Qing(Yanchi Research Station of the Mu Us Desert,School of Soil and Water Conservation,Beijing Forestry University,Beijing 100083,China;State Key Laboratory of Efficient Production of Forest Resource,Beijing Forestry University,Beijing 100083,China;Engineering Research Center of Forestry Ecological Engineering,Ministry of Education,Beijing Forestry University,Beijing 100083,China;Key Laboratory of National Forestry and Grassland Administration on Soil and Water Conservation,Beijing Forestry University,Beijing 100083,China;National Engineering Research Center for Tree Breeding and Ecological Restoration,Beijing Forestry University,Beijing 100083,China)

机构地区：[1]北京林业大学水土保持学院,宁夏盐池毛乌素沙地生态系统国家定位观测研究站,北京100083 [2]北京林业大学林木资源高效生产全国重点实验室,北京100083 [3]北京林业大学林业生态工程教育部工程中心,北京100083 [4]北京林业大学水土保持国家林业和草原局重点实验室,北京100083 [5]北京林业大学林木育种与生态修复国家工程研究中心,北京100083

出　　处：《植物生态学报》2024年第12期1637-1649,共13页Chinese Journal of Plant Ecology

基　　金：国家自然科学基金(U22A20504、32071844和32001373)。

摘　　要：种子性状对植物种群繁殖更新具有重要影响,了解黑沙蒿(Artemisiaordosica)种子性状对氮沉降及降水变化的响应,可为预测未来气候变化背景下荒漠植物群落演替方向提供理论基础。该研究以宁夏毛乌素沙地连续8年(2015–2022)的野外氮、水控制实验(自然降雨、增水20%、增水40%和0、20、60 kg N·hm^(–2)·a^(–1)全因子交互)平台为依托,测定了氮、水添加对黑沙蒿种子形态、生理和化学性状的影响;采用培养皿萌发实验并通过观测萌发种子数量计算各萌发指标,探究了各处理种子在两种培养温度下(25℃/15℃、20℃/10℃)的萌发特性。结果表明:(1)氮、水添加及其交互作用均显著改变了黑沙蒿种子质量、长度、宽度、曲率、体积、形状系数等形态性状,增水使种子变小,氮添加使种子变大,增水20%削弱了氮添加对种子变大的作用,增水40%时,氮添加使种子变小;(2)常温(25℃/15℃)下种子萌发率总体高于低温(20℃/10℃),低温下,种子萌发性状受亲本氮、水添加影响更大,且仅增水20%、40%处理下,种子萌发率更高;(3)氮、水添加处理下,种子长、宽、质量等形态大小性状调节扩散和幼苗建立功能,种子形状系数、2 h吸水率、萌发率和萌发速率共同调节种子萌发时间,单独增水或氮添加使黑沙蒿种子只倾向于单一功能(扩散建立或萌发)的变异,而同时增水与氮添加使黑沙蒿种子两类功能均发生变异。研究结果表明,黑沙蒿种群繁殖更新策略在全球气候变化中有较大的可塑性,可通过种子性状变异改变在氮沉降及降雨增多情形下的种子扩散建立与萌发功能策略。Aims Seed traits are of great significance for clarifying plant population reproduction and regeneration strategies.Exploring responses of Artemisia ordosica seed traits to nitrogen and water addition can improve our understanding of desert plant community succession in the context of global change.Methods The study was conducted based on a 8-year field water and nitrogen control experiment(2015-2022)in Mu Us Desert.A full factor interaction experiment of ambient precipitation,20%water increase,40%water increase and 0,20,60 kg N·hm^(−2)·a^(−1) were carried out to determine the morphological,physiological,chemical and germination traits of A.ordosica seed.Seed germination traits under each treatment at two temperatures(25℃/15℃ and 20℃/10℃)were explored by using the petri dish germination experiment and calculating the germination indexes by observing the number of seedling emergence.Important findings(1)Nitrogen and water addition,as well as their interactions,significantly influenced A.ordosica seed morphological traits,including seed mass,length,width,curvature,volume,form coefficient and other traits.Water addition resulted in smaller seeds while nitrogen alone led to larger seeds.However,20%water increase mitigated the effect of nitrogen increase on seed size.Conversely,with a 40%water increase,nitrogen addition caused smaller seeds.(2)Germination percentage was higher at normal temperature(25℃/15℃)than that at low temperature conditions(20℃/10℃).At low temperature,seed germination traits were more affected by water and nitrogen addition experienced by parental organisms,and when only adding 20%and 40%water,A.ordosica had higher germination percentage.(3)Under the treatments of water and nitrogen addition,the morphological traits such as seed length,width,quality jointly regulated function of dispersal and establishment while form coefficient,2 h water absorption,germination percentage and germination speed jointly regulated ecological function of germination timing.Adding water or nitrog

关 键 词：氮沉降 降雨增多 黑沙蒿 种子性状 萌发 繁殖 

分 类 号：S793.9[农业科学—林木遗传育种]