东北退化草原恢复演替系列羊草和寸草无性系种群构件营养繁殖特征比较OA北大核心CSTPCD

Populations of clonal herbaceous plants mainly regenerate by vegetative propagation. The age structure of modules of rhizomatous herbaceous plants generated by vegetative propagation is an important factor in population status analysis,and in the prediction of vegetation and restoration succession dynamics. In this study,we analyzed and compared the age structures of tillers and rhizomes,the productivity of tillers,the storage capacity of rhizomes,and the vegetative propagation capacity of both tillers and rhizomes at different ages between two major clonal herbaceous species,Leymus chinensis and Carex duriuscula,at five stages of restoration in the succession of degraded grassland in northeast China. The tillers of L. chinensis and C. duriuscula showed an expanding age structure,and the rhizomes exhibited a stable or expanding age structure at each stage of restoration succession. The tiller productivity and rhizome storage capacity of L. chinensis were greater than those of C. duriuscula at different stages of restoration succession. With the process of grassland restoration succession,the storage capacity of rhizomes of L. chinensis in the first age class showed a significant increasing trend,and the productivity of tillers of C. duriuscula in the second age class showed a significant decreasing trend. At the stages of restoration succession when L. chinensis and C. duriuscula coexisted,the vegetative propagation capacity of L. chinensis rhizomes was higher than that of C. duriuscula. Overall,the age structure characteristics of the modules of L. chinensis and C. duriuscula were similar at various stages of restoration succession. However,with the process of grassland restoration succession,the vegetative propagation strategy of the L. chinensis population to enhance the vegetative propagation capacity of young and prime tillers was more conducive to the maintenance and expansion of the population than that of the C. duriuscula population to only increase the vegetative propagation capacity of young tillers. Therefore,L. chinensis gradually replaced C. duriuscula as the dominant species in the community during succession.