草甸草原关键物种功能性状对长期放牧和停牧恢复的响应  

Response of Functional Traits of Key Species in Meadow Steppe to Long-Term Grazing and Grazing Exclusion

作　　者：司雨凡 李辉 李子好[2,3] 姜翠霞 郭昊南 杨培志 席杰军[1] 闫瑞瑞[2] 乌仁其其格[4] 山丹 辛晓平 SI YuFan;LI Hui;LI ZiHao;JIANG CuiXia;GUO HaoNan;YANG PeiZhi;XI JieJun;YAN RuiRui;WURENQIQIGE;SHAN Dan;XIN XiaoPing(College of Prataculture and Grassland,Northwest A&F University,Yangling 712100,Shaanxi;National Field Scientific Observation and Research Station of Hulunbuir Grassland Ecosystem/Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences,Beijing 100081;College of Ecology,Lanzhou University,Lanzhou 730000;School of Agriculture and Forestry,Hulunbuir University,Hulunbuir 021008,Inner Mongolia)

机构地区：[1]西北农林科技大学草业与草原学院,陕西杨凌712100 [2]呼伦贝尔草原生态系统国家野外科学观测研究站/中国农业科学院农业资源与农业区划研究所,北京100081 [3]兰州大学生态学院,兰州734000 [4]呼伦贝尔学院农林学院,内蒙古呼伦贝尔021008

出　　处：《中国农业科学》2023年第18期3693-3708,共16页Scientia Agricultura Sinica

基　　金：国家自然科学基金重点项目(32130070);国家重点研发计划(2021YFD1300500)。

摘　　要：【目的】植物功能性状对环境变化及外部干扰的响应,反映了植物的表型塑性、生存策略及适应能力。通过长期放牧条件下草原植物功能性状的变化及停止放牧后的恢复响应研究,为草原恢复管理的研究提供理论依据。【方法】探究了生长季不同放牧梯度下呼伦贝尔草甸草原6个关键物种(羊草、日阴菅、糙隐子草、斜茎黄芪、裂叶蒿、细叶白头翁)叶片功能性状(叶片干重、叶片含水量、叶面积、比叶面积、叶片氮含量、叶片磷含量、叶片C/N、叶片N/P)的变化,以及生长季停止放牧后的草甸草原关键物种叶片功能性状的即时恢复响应。【结果】(1)6个关键物种的相对生物量和重要值随放牧强度增加而减小,轻度和重度放牧强度停止放牧后的值大于继续放牧。(2)6个关键物种的叶片干重、叶片C/N整体随放牧强度的增加呈减小趋势;叶片含水量、比叶面积、叶片氮含量整体随放牧强度的增加呈增大趋势;除裂叶蒿外各物种叶面积都随放牧强度增加而减小;叶片磷含量除糙引子草外都随放牧强度增加呈增大趋势;随放牧强度增加,羊草、日阴菅、糙隐子草、细叶白头翁的叶片N/P整体呈增大趋势,而斜茎黄芪、裂叶蒿呈减小趋势。(3)停止放牧后,重度放牧的恢复程度高于轻度放牧,6个关键物种的功能性状整体恢复较好,叶片干重、叶片含水量、叶面积、比叶面积、叶片N/P都表现为正响应、叶片磷含量呈现负响应,叶片氮含量、叶片C/N在6个关键物种中正负响应不一,叶片氮含量的正响应少于负响应,叶片C/N的正响应多于负响应。(4)禾草类的叶片形态学性状、杂类草的养分特征对停止放牧后的恢复更敏感,且叶片干重、叶面积和叶片磷含量对放牧强度和物种的交互作用的响应更为显著。停止放牧后,随6个关键种叶面积、叶片氮含量、叶片N/P的增加,叶片干重也在增加。【【Objective】The response of plant functional traits to environmental changes and external disturbances reflects the phenotypic plasticity,survival strategies and adaptability of plants.The study on the changes of functional traits of grassland plants under long-term grazing and the recovery response after stopping grazing can provide a theoretical basis for grassland restoration management.【Method】In this study,the changes of leaf functional traits(leaf dry mass,leaf total water content,leaf area,specific leaf area,leaf nitrogen content,leaf phosphorus content,leaf C/N raito,leaf N/P ratio)of six key species(Leymus chinensis,Carex pediformis,Cleistogenes squarrosa,Astragalus adsurgens,Artemisia tanacetifolia L.,Pulsatilla turczaninovii)in Hulunbuir meadow steppe under different grazing intensities during growing season were studied.The immediate recovery response of leaf functional traits of key species in meadow steppe after stopping grazing during growing season was discussed.【Result】(1)The relative biomass and importance values of the six key species decreased with the increase of grazing intensity,and the values of light and heavy grazing intensity after stopping grazing were greater than that after continuing grazing.(2)The leaf dry mass and leaf C/N ratio of six key species decreased with the increase of grazing intensity;the leaf total water content,specific leaf area and leaf nitrogen content increased with the increase of grazing intensity;the leaf area of all species except Artemisia tanacetifolia L.decreased with the increase of grazing intensity;the leaf phosphorus content increased with the increase of grazing intensity except Cleistogenes squarrosa;with the increase of grazing intensity,the leaf N/P ratio of Leymus chinensis,Carex pediformis,Cleistogenes squarrosa,Pulsatilla turczaninovii showed an increasing trend,while that of Astragalus adsurgens,Artemisia tanacetifolia L.decreased.(3)After stopping grazing,the resilience of heavy grazing was higher than that of light grazing,and the f

关 键 词：长期放牧 停止放牧 叶片功能性状 恢复力 草甸草原 

分 类 号：S812[农业科学—草业科学]