降水量和短期极端干旱对典型草原植物群落及优势种羊草(Leymus chinensis)叶性状的影响  

Effects of Precipitation and Short Term Extreme Drought on Leaf Traits in Inner Mongolia Typical Steppe

作　　者：岳喜元 左小安 庾强 徐翀[4] 吕朋 张晶 Yue Xiyuan;Zuo Xiaoan;Yu Qiang;Xu Chang;Lv Peng;Zhang Jing(Urat Desert Grassland Research Station,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China;University of Chinese Academy of Sciences,Beijing 100049,China;Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences,Beijing lO0081,China： 4.College of Pastoral Agriculture Science and Technology,Lanzhou University,Lanzhou 730000,China)

机构地区：[1]中国科学院西北生态环境资源研究院乌拉特荒漠草原研究站,甘肃兰州730000 [2]中国科学院大学,北京100049 [3]中国农业科学院农业资源与农业区划研究所,北京100081 [4]兰州大学草地农业科技学院,甘肃兰州730000

出　　处：《中国沙漠》2018年第5期1009-1016,共8页Journal of Desert Research

基　　金：国家自然科学基金项目(41622103;41320104002);国家重点研发计划项目(2016YFC0500506)

摘　　要：植物叶性状在植物响应环境变化中具有重要作用。在气候变化的背景下,典型草原植物叶性状如何响应降水格局与短期极端干旱还不十分清楚。利用野外控制试验,研究了降水量(323 mm和236 mm)和短期极端干旱(生长季减雨66%和生长季干旱60 d)对典型草原植物群落及优势植物羊草(Leymus chinensis)叶性状的影响。结果表明:降水格局显著影响着植物群落和羊草的叶性状(P<0.05),短期极端干旱对典型草原群落和羊草叶面积具有显著影响(P<0.05)。随着降水量的减少,群落和羊草的叶面积与叶干物质含量降低,而比叶面积与叶片氮含量增加。降水格局与短期极端干旱交互作用显著影响着群落的叶面积与叶片氮含量(P<0.05),323 mm降水量下短期极端干旱显著降低了叶面积,266 mm降水量下生长季干旱60 d增加了叶片氮含量。降水格局与短期极端干旱交互作用也显著影响着羊草叶面积与比叶面积(P<0.01),323 mm降水量下短期极端干旱降低了叶面积,266 mm降水量下生长季干旱60 d显著增加了比叶面积。回归分析表明,不同处理下羊草叶面积、叶干物质含量、叶片氮含量能较好地解释群落叶性状。典型草原植物群落通过优势植物的主要叶性状改变来适应降水格局变化,而通过叶面积改变来适应短期极端干旱。Leaf functional traits play an important role in the response of plants to environmental change. How leaf traits respond to precipitation pattern and short term extreme drought is still not very clear in Inner Mongolia typical steppe under climate change. By using manipulative experiment in the field, the leaf traits of dominant species Leymus chinensis and community leaf traits were studied under precipita- tion pattern （323 m and 255 mm） and short terra extreme drought （precipitation reduced by 55% from May to September; drought for 60 days from June to July） in Inner Mongolia typical steppe. The results showed that precipitation had significant effects on leaf traits L. chinensis and community leaf traits （P〈 0.05）, and short term extreme drought significantly affected leaf area of L. chinensis and community weighted means of leaf area. Specifically, leaf area and leaf dry matter content of L. chinensis and com- munity weighted means of leaf area and leaf dry matter content decreased from high precipitation site to low precipitation site, while leaf nitrogen content increased. The interaction of precipitation pattern and short term extreme drought significantly affected community weighted means of leaf area and leaf nitro- gen content （P〈0.05）. Short term extreme drought significant decreased community weighted means of leaf area in 323 mm, and drought for 60 days significantly increased community weighted means of leaf nitrogen content in 255 mm. Precipitation pattern and short term extreme drought interactively affected leaf area and specific leaf area of L.chinensis （P〈0.01）. Short term extreme drought significantly de- creased leaf area of L.chinensis in 323 mm, and drought for 60 days increased specific leaf area in 256 mm. Leaf area, leaf dry matter content and leaf nitrogen content of L. chinensis can well explain commu- nity leaf traits under control and short term extreme drought treatments. Dominant species can alter the key leaf traits to acclimate to precipitation pattern,

关 键 词：叶性状 短期极端干旱 降水 羊草(Leymus chinensis) 典型草原 

分 类 号：Q948.11[生物学—植物学]