库布齐沙地不同沙丘类型植物多样性研究

Study on Plant Diversity of Different Dunes in the Eastern Kubuqi Desert

选择库布齐沙漠东缘三种沙丘类型(固定沙丘、半固定沙丘、流动沙丘)为研究对象,采用样线与样方结合法定位监测调查10年来沙化草地植被多样性的动态变化、生物量变化,结合气候数据,探讨多样性与生产力、生态系统的关系,为库布齐沙漠的退化草地恢复与重建提供科学依据。结果表明:(1)三种类型沙丘的地上总生物量随年限的增加而增长,半固定沙丘中灌木比重升高而草本比重降低。(2)物种丰富度呈递增趋势,Shannon-Wiener指数、Simpson指数和Pielous均匀度指数在每种类型沙丘上变化趋势一致,在固定沙丘和半固定沙丘几乎保持不变,而在流动沙丘上递增。(3)相关性分析,固定、流动沙丘中,物种多样性与生物量呈正相关(P>0.05),在半固定沙丘中物种丰富度与生物量呈显著性正相关(P<0.05),地上生物量与年降水量呈正相关关系。

The objective of our study was to investigate the dynamic changes of three types of dunes(Fixed dune,Semi-fixed dune,Moving dune)in the eastern Kubuqi Desert during the past 10 year.Plant diversity,biomass were detected using the quadrat and line intercept method.The relationship between diversity,productivity and ecosystem is discussed basing on climate data,which provides scientific basis for restoration and reconstruction of degraded grassland in Kubuqi desert.The results showed that:(1)The total aboveground biomass of three types of dunes increased with the growth of the year,and the proportion of shrubs in Semi-fixed dune increased while that of herbs decreased.(2)The species richness showed an increasing trend,Shannon-Wiener index,Simpson index and Pielous evenness index were consistent on each type of dunes,and almost remained unchanged in Fixed and Semi-fixed dune,and increased on the Moving dune.(3)Species diversity was positively correlated with biomass,in Fixed and Moving dune,the species richness in Semi-fixed dunes was significantly positively correlated with biomass(P<0.05),and the aboveground biomass was positively correlated with annual precipitation.