荒漠植被草本层片植物对火因子的响应  

Response of Desert Herb Synusia to Fire

作　　者：贺郝钰[1,2] 李新荣[1] 李小军[1] 苏洁琼[1,2] 刘扬[1,2] 郭群[1,2] 

机构地区：[1]中国科学院寒区旱区环境与工程研究所沙坡头沙漠研究试验站,甘肃兰州730000 [2]中国科学院研究生院,北京100049

出　　处：《中国沙漠》2010年第4期885-890,共6页Journal of Desert Research

基　　金：国家自然科学基金项目(40825001;40701002)资助

摘　　要：火因子是生态系统中重要的干扰因素,对生态系统格局与过程有着深远的影响。采用人为放火的方法研究了草原化荒漠草本层片植物物种丰富度、地上部生物量、植物多度以及高度等群落学特征对火因子的响应。结果表明,火烧后两年(2008—2009年),火烧样地单位面积中草本层片植物物种丰富度有所降低;植物多度多于对照样地,但无显著性差异(P>0.05)。火烧后当年,火烧样地中草本植物地上部生物量显著高于对照样地(P<0.05),第2年地上部生物量无显著性差异(P>0.05),说明火烧后当年有利于提高荒漠生态系统生物生产力,而第2年该效应消除。火烧后当年,研究区3种主要草本植物多根葱、无芒隐子草和茵陈蒿的高度受到了抑制,第2年其高度较对照样地又有所增长,但另一主要植物刺蓬则与其他3种植物反应相反,这可能与荒漠草本植物种不同生长特性有关。Fire is a significant influencing factor that affects ecosystem pattern and process. In an experiment of man-made grassland burning, the responses to fire of plant abundance, aboveground biomass, species richness, dominant species height were studied. The results are as follows. In the initial two post-fire years （2008--2009）, the species richness of herbaceous synusia in burned site decreased, and the plant abundance was higher than that in the unburned sites, but the difference wasn＇t remarkable （P〉0.05）. In the first post-fire year （2008）, the aboveground biomass in burned site was significantly higher than that in the unburned sites （P〈0. 05）; In 2009 the difference wasn＇t remarkable （P〉0. 05）. In other words, fire can only increase the productivity of desert ecosystem in the first post-fire year, has no effect in the second year. The height growth of three dominant species Allium polyrhizum, Cleistogennes songorica and Artemisia capillaris was restrained in the first post-fire year in burned site, and showed a slight more increase than that in check site in the second year. Whereas, another dominant species Cornulaca alaschanica appeared opposite response to fire, which was probably related to different growth characteristics of desert plants.

关 键 词：火烧 荒漠化草原 草本层片 物种丰富度 地上部生物量 

分 类 号：S812.8[农业科学—草业科学]