Abstract: In order to understand how the Yangtze River shelter forest community highness class construction be made of, we investigated plant community highness class number of plants, cover degree and number of species in 11 model of run-off plots of vegetation types in this area. The plant community highness class was regarded as coordinate axis. A series of new targets and equations, e. g. lost stable rate of plant number, cover degree fluctuative rate and species sharing degree, were put forward, for examining plant population or community dynamics and community construction. With this targets and equations, we quantitatively analyzed this series of highness class constructions of run-off plots of vegetation types and compared these models′advantages and shorters for their soil and water conservation effect.