Population Dynamics of Wild Cotoneaster horizontalis in the Maidiping of Fengdu County,Southwest China

Cotoneaster horizontalis is a good ornamental plant and has a wide range of applications in garden.In order to provide scientific basis and reference for developing and protecting the resources of wild C.horizontalis in Nantianhu region,a sample plot survey of the C.horizontalis population was carried out at Mediping in Nantianhu Village of Fengdu County,Southwest China,on the basis of which the change pattern of the population of C.horizontalis was analyzed,its static life table was prepared,its survivorship curve,mortality curves and killing power curve were plotted and its population structure dynamics was calculated.The results showed that the average density of Cotoneaster horizontalis decreased with increasing perimeter-class,which suggested a negative correlation between density and perimeter-class,with a correlation coefficient of-0.193 63(p0.01),which showed that the edge effect of C.horizontalis population was not great The survivorship curve of C.horizontalis belonged to the Deevey-Ⅲ type.The mortality and killing power rate peaks of C.horizontalis population were in the first and eighth age grades.The age structure of C.horizontalis was close to the type of growth,and Vpi=0.066 837,closed to zero,which showed its population was almost stabilized.