Response of the clonal plant Carex brevicuspis to clipping disturbance in Dongting Lake Wetlands: the role of bud banks in compensatory growth

Compensatory growth following disturbance is a prevalent phenomenon in clonal plants within natural ecosystems, and the bud bank serves as a crucial source for population regeneration in clonal plants. This study focused on Carex brevicuspis, a dominant species in the Dongting Lake wetlands, and established two experimental groups—severe clipping and mild clipping—along with one control group. By collecting and analyzing data on growth performance, regenerative potential, and reproductive strategy, the responses of the Carex brevicuspis population and its bud bank to different clipping intensities were investigated. The results demonstrated that, clipping led to a decline in the growth performance of the Carex brevicuspis population. Compared with the control group, severe clipping significantly reduced plant density, height, aboveground biomass, and belowground biomass, while mild clipping significantly decreased plant height and aboveground biomass. Clipping impaired the regenerative potential of the Carex brevicuspis population; basal bud density was significantly reduced under all clipping treatments, and apical bud density was also significantly decreased following severe clipping. Mild clipping had no effect on the reproductive strategy of Carex brevicuspis, whereas severe clipping altered its reproductive strategy, shifting it from guerrilla-type growth to phalanx-type growth. Overall, the Carex brevicuspis population exhibited a certain degree of resistance to clipping stress; however, excessively high clipping intensity adversely affected the regenerative capacity of the Carex brevicuspis population. This study provides a scientific basis for plant species conservation, waterbird habitat management, and the development of ecological restoration strategies in the context of habitat changes in the Dongting Lake wetlands.