Effects of water and nitrogen on growth and relative competitive ability of introduced versus native C_(4)grass species in the semi-arid Loess Plateau of China

作     者：DING Wenli XU Weizhou GAO Zhijuan XU Bingcheng DING Wenli;XU Weizhou;GAO Zhijuan;XU Bingcheng

作者机构：State Key Laboratory of Soil Erosion and Dryland Farming on the Loess PlateauNorthwest A&F UniversityYangling 712100China College of Life ScienceYulin UniversityYulin 719000China Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water ResourcesYangling 712100China 

出 版 物：《Journal of Arid Land》 (干旱区科学（英文版）)

年 卷 期：2021年第13卷第7期

页      面：730-743页

核心收录：

学科分类：07[理学] 0713[理学-生态学] 

基　　金：The study was supported by the National Natural Science Foundation of China(41371509,41771553) the Intergovernmental International Cooperation on Science and Technology Innovation under the Ministry of Science and Technology of People's Republic of China(2018YFE0112400) 

主　　题：aggressivity nitrogen deposition relative competitive ability root trait water stress 

摘      要：Switchgrass is an introduced C_(4)grass in the semi-arid Loess Plateau of China,but there is a lack of information to assess its ecological invasive *** this study,Old World bluestems(native C_(4)grass)and switchgrass were sowed at five mixture ratios(8:0,6:2,4:4,2:6 and 0:8)under two soil water levels(80%field capacity(FC)and 40%FC)and two nitrogen(N)treatments(0 and 100 mg N/kg dry soil,termed N0-unfertilized and N1-fertilized treatments,respectively)in a pot experiment in ***,root morphological traits and relative competitive abilities of these two species were *** showed that biomass of both species was significantly greater under 80%FC or N fertilization,and switchgrass had a relatively larger root:shoot ratio(RSR).Total root length(TRL)and root surface area(RSA)of switchgrass were significantly higher under 80%FC irrespective of N treatment,while those of Old World bluestems were only significantly higher under N fertilization.N had no significant effect on TRL and RSA of switchgrass,while RSA of Old World bluestems significantly increased under 80%FC and N *** 40%FC and N0-unfertilized treatment,the aggressivity of Old World bluestems was larger than zero at 2:6 and 4:4 mixture ratios of two species,whereas it was close to zero at 6:2 mixture *** competitive ability of switchgrass significantly increased under 80%FC or N *** aggressivity of Old World bluestems was negative at 6:2 mixture ratio under 80%FC and N fertilization,while it was positive at 2:6 mixture *** may become more aggressive when N deposition or rainfall increases,while a proper mixture ratio with appropriate water and N management could help with grassland management in the semi-arid Loess Plateau.