全球气候变化对全球生态环境的影响越来越引起人们的关注。荒漠植被作为荒漠生态系统的一个重要组分,对全球气候变化的响应较为敏感。本文以准噶尔盆地南缘的典型荒漠植被梭梭(Haloxylon ammodendron)作为研究对象,采用OTC(Open top chamber)开顶箱方式模拟温室效应。通过研究增温处理对梭梭同化枝气体交换参数(PAR,Tleaf,Pn,Gs)、丙二醛(MDA)含量、抗氧化酶(SOD,POD,CAT)活性和渗透调节物质(Pro,SS,Pr)含量的影响,为荒漠植被在全球进一步变暖下产生的反映提供科学的预判和依据。结果表明:增温组梭梭的PAR,Pn及Gs均低于对照组;而Tleaf,MDA含量、抗氧化酶(SOD,POD,CAT)活性及渗透调节物质(Pro,SS,Pr)含量均高于对照组,说明增温生境下梭梭受胁迫程度加强。与此同时,也更进一步预示着未来全球气候变化格局下,梭梭将面临的一个更为严峻的生存挑战。
英文摘要:
The impact of global climate change on the global ecological environment,especially the responses of desert vegetation to global climate change,have increasingly aroused the concerns worldwide.The desert vegetation,as an important component of desert ecosystem,is more sensitive to the global climate change.In this paper,we selected the typical desert vegetation of the southern margin of Junggar Basin, Haloxylon ammodendronas the research object,and used OTC(Open top chamber)Open top way to simulate the greenhouse effect.Through studying the effects of warming treatment on gas exchange parameters(PAR,Tleaf,Pn,Gs),malondialdehyde(MDA)content,antioxidase(SOD,POD and CAT)activities, osmotic adjustment substances(Pro,SS and Pr)content of Haloxylon ammodendron,the study could provide scientific prediction and basis for the responses of desert vegetation in the predicted further global warming condition.Results showed that the PAR,Pn,and Gs of warming group were lower than those of control group.However,other physiological indexes of warming group,including Tleaf,MDA content,SOD,POD,CAT activities,Pro,SS and Pr content,were all higher than those of control group. These revealed that the degree of stress of Haloxylon Ammodendron was strengthened under the condition of warming.Meanwhile,it further indicates that under the future pattern of global climate change condition Haloxylon ammodendron will face a more severe challenge of survival.