Small-scale point pattern analysis based on different null models for detecting spatial patterns of dominant species in Sanjiang Plain,China

To study the spatial distribution pattern of plant populations in marsh is supplementary for spatial pattern theory because the distinctive environmental conditions. Thus, we analysis the spatial distribution pattern of main dominant species (C. lasiocarpa, C. pseudocuraica, D. angustifolia and G. spiculosa) by point pattern analysis based on different null models. The plot was divided into 256 contiguous 25x25 cm quadrats, as the basic unit of vegetation survey, using the bamboo pole and the white rope. Nineteen Monte-Carlo simulations were used to generate 95% confidence envelopes. Our results showed that: The four main dominant species mainly depart from complete spatial randomness (CSR) and shows aggregation in 0-200cm scales, but have varying degrees of deviation: The C. lasiocarpa, C. pseudocuraica and G. spiculosa depart from poisson cluster process (NS) in small-scale, except D. angustifolia; The C. lasiocarpa and G. spiculosa depart from nested double-cluster process (DC) in a very small-scale, but not significant.