[Fractal properties of the spatial pattern of rare and endangered plant populations in Houhe Nature Reserve in Hubei: Box-counting dimension].

The fractal properties of the spatial distribution pattern of 4 dominant plant populations and 7 rare and endangered plant populations were reflected through the box-counting dimensions. The results showed that the box-counting dimensions of 4 dominant populations ranged between 1.346 and 1.414, and occupied relatively larger ecological spaces in the community. Camellia cuspidata population occupied the largest ecological space because of its biggest box-counting dimensions. However, most of other populations occupied relatively smaller spaces due to their smaller values of the box-counting dimensions. The box-counting dimensions of 7 rare and endangered populations were smaller than 1 except Dipteronia sinensis population. The inflexion scales of 11 populations covered the range from 5 m to 12.5 m. According to the self-similarity of the fractal, the distribution pattern types under certain scales larger than the inflexion scale could be inferred as similar, and the results partly proved the ideas. The populations of Disopyros lotus, Pterostyrax psilophyllus, Davidia involucrata, Tetracentron sinense and Aesculus wilsonii were changed at the inflexion scale, and other 6 populations had the same distribution pattern types despite of the scale changed.