Spatial Heterogeneity Dynamics of Canopy Structure in a Montane Evergreen Broadleaved Forest Following a Natural Disturbance in North Guangdong

The spatial heterogeneity dynamics of canopy structure were successively investigated (from 2008 to 2010) in Chebaling montane evergreen broadleaved forest following an ice storm in 2008.We used hemispherical photography to acquire canopy pictures and geostatistics to analyze the spatial heterogeneity and spatial autocorrelation of canopy structure.The mean,standard deviation,variation coefficient,minimum and maximum of canopy openness,and spatial heterogeneity of canopy structure decreased from 2008 to 2010,and the values were more similar to each other in 2009 and 2010.Geostatistical analysis indicated that semivariance function of the 2008 canopy structure fitted with the pure nugget model and demonstrated stochastic factors in interpreting canopy structure,while 2009 and 2010 fitted with the spherical model and demonstrated structural factors,especially in 2010.No spatial autocorrelation was found in the canopy structure of 2008,while spatial autocorrelation became stronger with time.Our results indicated that canopy structure could recover to its pre-disaster level gradually without human intervention and reflect spatial distribution in natural state conditions.