元谋干热河谷Savanna草地优势植物的种间关系  

Interspecific relationships in Savanna grassland in Yuanmou,a dry-hot valley upstream of the Yangtze River

作　　者：何光熊[1] 闫帮国[1] 纪中华 史亮涛[1] 樊博[1] 范建成[1] 张梦寅[1] HE Guang- xiong;YAN Bang- guo;JI Zhong -hua;SHI Liang- tao;FAN Bo;FAN Jian -cheng;ZHANG Meng- yin(Institute of Tropical Eco agricultural Sciences,Yunnan Academy of Agricultural Sciences,Yuanmou 651300,China;Insti tute of Agricultural Environment and Resources,Y-unnan Academy of Agricultural Sciences,Kunm ing 650205,China)

机构地区：[1]云南省农业科学院热区生态农业研究所,云南元谋651300 [2]云南省农业科学与农业环境资源研究所,云南昆明650205

出　　处：《草业学报》2018年第6期62-71,共10页Acta Prataculturae Sinica

基　　金：国家自然科学基金项目(31460127); 农业部现代农业产业技术体系专项资金(CARS-19)资助

摘　　要：对逆境群落植物种间关系进行剖析是理解群落组配规则及物种适应性与逆境环境条件间相互关系的重要基础。采用方差比率(VR)法、χ~2检验结合Jaccard指数法以及Spearman秩相关系数法对元谋干热河谷Savanna草地18个优势植物的种间关系进行分析。结果表明:1)元谋干热河谷Savanna草地植物整体的种间关系主要呈现显著的负关联,优势物种间存在较高的资源竞争或生态关系的相互排斥;2)18个优势物种间联结性较弱,在同一样方中18个优势物种间共同出现的频率较低,具有独立分布的特点;Spearman秩相关分析结果显示,由18个优势物种组成的153个种对中显著相关的种对31对,呈极显著相关的种对18对,分别占总种对数的20.3%和11.8%,主要呈现正相关关系;3)18个优势种划分为4个生态种组,优势种橘草、拟金茅、孔颖草及广布种扭黄茅是干热河谷Savanna草地种间关系维持的关键种。该结论提示干热河谷Savanna草地物种间存在较高的资源竞争或生态关系的相互排斥,具有明显的独立分布特征,因而群落易受到环境或人为因素的影响。该区域植被恢复宜优先恢复扭黄茅等关键种,而功能性植被重建应按群落的功能需求恢复及保护相适应的生态种组物种。Understanding the interspecific relationships in harsh environments can reveal how plant species adapt and assemble into communities under disadvantageous conditions.In this study,we used variance tests to detect species＇ associations,and used chi-squared tests,the Jaccard index,and Spearman＇s rank correlation analyses to analyze interspecies associations and correlations for 18 dominant species from Savanna communities in Yuanmou,a dry-hot valley of the Jinsha River,upstream of the Yangtze River in southwest China.The results showed that：1）There were significant negative correlations among Savanna grassland plants in Yuanmou.These negative correlations were indicative of strong resource competition or difficult ecological relationships among dominant species;2）The 18 dominant species were weakly inter-associated,and had a low frequency of common occurrence in plots.Spearman＇s rank correlation analyses of the 18 dominant species revealed positive interspecific correlations,with 31 significant or very significant species pairs and 18 very significant species pairs（20.3% and 11.8%,respectively,of a total of 153 species pairs）;3）The 18 dominant species were divided into four specific ecological groups.Among these species,Cymbopogon goeringii,Eulaliopsis binata,Bothriochloa pertusa and widespread species Heteropogon contortus were key band species bundled with other species to form communities in the dry-hot ecosystem in Yuanmou valley.These results suggested that Savanna grassland plants have strong resource competition and/or difficult ecological relationships.The main species showed insolated distribution patterns and the communities were easily disturbed.In practice,species like H.contortus should be prioritized as key species for vegetation restoration,and functional communities should be protected to preserve groups of species that are adapted to the harsh conditions of the hot-dry ecosystem.

关 键 词：干旱 逆境 群落结构 生态种组 

分 类 号：Q948[生物学—植物学]