期刊名称：ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences
印刷版ISSN：2194-9042
电子版ISSN：2194-9050
出版年度：2015
卷号：XL-1/W5
页码：163-168
DOI：10.5194/isprsarchives-XL-1-W5-163-2015
出版社：Copernicus Publications
摘要：Evaluating the interactions of woody plants has been a major research topic of ecological investigations in arid ecosystems. Plant-plant interactions can shift from positive (facilitation) to negative (competition) depending on levels of environmental stress and determine the spatial pattern of plants. The spatial distribution analysis of plants via different summary statistics can reveal the interactions of plants and how they influence one another. An aggregated distribution indicates facilitative interactions among plants, while dispersion of species reflects their competition for scarce resources. This study was aimed to explore the intraspecific interactions of eshnan ( Seidlitzia rosmarinus ) shrubs in arid lands, central Iran, using different summary statistics (i.e., pair correlation function g( r ), O-ring function O( r ), nearest neighbour distribution function D( r ), spherical contact distribution function Hs( r )). The observed pattern of shrubs showed significant spatial heterogeneity as compared to inhomogeneous Poisson process (α=0.05). The results of g( r ) and O( r ) revealed the significant aggregation of eshnan shrubs up to scale of 3 m (α=0.05). The results of D( r ) and Hs( r ) also showed that maximum distance to nearest shrub was 6 m and the distribution of the sizes of gaps was significantly different from random distribution up to this spatial scale. In general, it was concluded that there were positive interactions between eshnan shrubs at small scales and they were aggregated due to their intraspecific facilitation effects in the study area
关键词：Eshnan; Dryland; Modelling; Spatial distribution; Summary statistic; Irano-Turanian zone
