Abstract: The spatial-temporal variations of Caragana korshinskii vegetation growth were investigated based on the 23 a monitoring data on fixing plots of Caragana korshinskii plantations on terrace and non-terrace barren land in Guyuan, Ningxia Hui Atonomous Region. The investigation was carried out in different slope positions and with different ages of the plantations, including young-age period (1-7 a), middle-age period (8-15 a) and old-age period (16-23 a). The results showed: The plant height of C. korshinskii was affected by the slope position and the soil preparation methods. The change tendencies of average heights showed that lower slope>middle slope>upper slope in juvenile period, and upper slope>middle slope>lower slope in middle period. Compared with the non-terrace barren land, the plant height of leveled terrace were improved by 23.48%～45.33% in both young-age period and middle-age period, while there were no significant differences in the heights in the old-age period. With the slope position increased, the individual branches number, ground diameter and biomass decreased. Compared with the non-terrace barren land, the branches number, ground diameter, aboveground biomass and underground biomass of level terrace were improved by 26.79%-78.82%, 37.50%-50.00%, 3.50%-91.97%, and 19.59%-50.17%, respectively. The growth of C. korshinskii fit the logistic curve model. It is concluded that the best time for utilizing C. korshinskii is the middle period according to the obtained results.

Key words: Caragana korshinskii vegetation, spatial-temporal variations, analysis of variance, Logistic model, multiple linear regressions