浑善达克沙地赖草分株种群与土壤资源异质性分析  

Hetergeneityies of Leymus secalinus ramet population and it's soil resources in the Otindag Sandland

作　　者：朱选伟[1] 刘海东[1] 梁士楚[1] 叶永忠[2] 董鸣[1] 

机构地区：[1]中国科学院植物研究所植被数量生态开放研究重点实验室,北京100093 [2]河南农业大学农学院,河南郑州450002

出　　处：《生态学报》2004年第7期1459-1464,共6页Acta Ecologica Sinica

基　　金：中国科学院知识创新重大资助项目 ( KSCX1-0 8-0 2 )~~

摘　　要：对浑善达克沙地低湿滩地、滩地 -风沙沉积过渡区到风沙沉积区的赖草分株数、地上生物量、土壤水分和养分异质性进行了研究。结果表明 ,从低湿滩地、滩地 -风沙沉积过渡区到风沙沉积区 ,赖草的分株数和地上生物量与养分含量具有不同的变化趋势。赖草的分株数在 3种生境中都存在空间自相关 ,并且 ,从低湿滩地、过渡区到风沙沉积区空间自相关的变程逐渐增加。地上生物量同样存在空间自相关 ,但变程以过渡区最大 ,风沙沉积区最低。土壤水分仅仅在风沙沉积区存在空间自相关。在 3种生境条件下 ,土壤全氮和有机质的空间分布格局相似 ,都在低湿滩地和过渡区存在空间自相关且变程相似 ,在风沙沉积区不存在空间自相关。赖草的空间分布格局在低湿滩地为偏离随机适度聚集的分布格局 ,在过渡区近似于聚居分布 。Clonal plants can exploit resources with heterogeneous patterns by ramets anchoring in different patches. They can be very successful and can dominate many ecosystems. The Otindag Sandland is a semi-arid area in China and Leymus secalinus is a dominant clonal grass in the Otindag Sandland. The objectives of this study were to investigate the spatial pattern in Leymus secalinus and of resource heterogeneity in the Otindag Sandland. Field investigation was conducted in the center of the Otindag Sandland, Zhenglan County, Inner Mongolia, China (42°53′～42°58′N, 116°01′～116°08′E). One pot was positioned at random in the lowland meadow, the ecotone of lowland meadow to sand accretion area and the sand accretion area, respectively. A plot consisted of a square grid divided into 20 × 20 subplots of 20 × 20 cm^2 each. Number of ramet of Leymus secalinus in a subplot was counted. Materials of L. secalinus' aboveground were harvested and taken back to the laboratory, then oven-dried at 70℃ to the constant weight. And the soil water content, organic matter and N total in each subplot were determined. Using semivariance analysis, heterogeneity of number of ramet and aboveground biomass in L. secalinus, soil water content and soil nutrient were analyzed. And spatial pattern in L. secalinus was investigated by lacunarity analysis. Results showed that there was different tendency in the changes of number of ramet and aboveground biomass in Leymus secalinus, soil water content and soil nutrient from the lowland meadow, the ecotone of lowland meadow to the sand accretion area. The distribution of number of ramet in L. secalinus was significant spatial autocorrelation in the lowland meadow and the ecotone and the sand accretion area. And their ranges increased from the lowland meadow, the ecotone of lowland meadow to the sand accretion area. The soil water content was only autocorrelation in the sand accretion area. The spatial distribution of N total and C organic was similar in these habits. In the lowland m

关 键 词：克隆植物 异质性 赖草 土壤养分 土壤水分 空间格局 

分 类 号：Q948.15[生物学—植物学]