Dynamics On Experimental Population At Simulated Later Restoration Succession Stage For Degenerated Meadow

Leymus chinensis is clonal plant which is a long rhizome typical gramineae grasses, existing in the form of a dominant species, Carex duriuscula and Hierochloe glabra are two important companion species on Leymus chinensis meadow in northeast of China. In the process of degradation, C. duriuscula and H. glabra often takes advantage of community. Population dynamics between L.chinensis and other companion species were the key point during restoration succession. By transplanting the different proportion in the experiment community, the research did a continuous observation on population dynamics of experimental populations, and revealed that the population dynamic and population status changes in the community during restoration succession. They have great contribution to restoration succession theory and restoration practice of meadow ecosystem.In this work we studied the population dynamics of L. chinensis and C. duriuscula which grown in each transplanted spot ( transplanted proportion of L. chinensis and C. duriuscula were 1:0, 1:1, 1:2, 1:3, 1:4, 1:5 and 1:6, respectively ) in 2008 and 2009 continuously. And we analyzed the same as above of L. chinensis, H. glabra and C. duriuscula which grow in each spot (transplanted proportion of L. chinensis and H. glabra were 0:0:1, 1:1:1, 1:1:2, 1:2:3, 1:2:4, 1:3:5 and 1:3:6, respectively ) in 2008 and 2009 continuously. We researched on dynamics and the structures of experimental population in simulated restoration succession at later stage for degenerated Leymus chinensis meadow.Researches on spatio-temporal changes of L. chinensis and C. duriuscula in each transplanted proportion approved that:In the seventh year and the eighth year at later stage of the simulated restoration succession, the number of tiller and its biomass, the rhizomes length and its biomass and the number of buds of L. chinensis and C. duriuscula in each transplanted proportion had no significant differences in the two years and in the great mass of spots. They kept the stability in time and in all spots. The relationship between the two experimental populations has been very stable.Researches on spatio-temporal changes of L. chinensis, H. glabra and C. duriuscula in each transplanted proportion approved that:In the seventh year and the eighth year at later stage of the simulated restoration succession, the number of tiller and its biomass, the rhizomes length and its biomass, the number of buds of L. chinensis, H. glabra and C. duriuscula in each transplanted proportion had no significant differences in the two years and in the great mass of spots. They kept the stability in time and in all spots. The relationship between the three experimental populations has been stable relatively. Researches on age structure of L. chinensis and C. duriuscula in each transplanted proportion approved that:Age structure of the tiller number and the rhizomes length of L. chinensis and C. duriuscula kept stability relatively. And the young age classes of tiller number accounted for larger proportion showing the characteristics of the expansive structures; while age structure of rhizomes length presented stably.Researches on age structure of L. chinensis, H. glabra and C. duriuscula in each transplanted proportion approved that:Age structure of the tiller number and the rhizomes length of L. chinensis and C. duriuscula kept stability relatively. And young age classes of tiller number accounted for larger proportion showing the characteristics of the expansive structures; while rhizomes length indicated the expansive or stable structures.