Author(s): Qing Wang; Baoshan Cui; Tian Xie
Linked Author(s):
Keywords: Plant recruitment; Seed retention; Bare patch; Facilitation; Microtopographic structure
Abstract: Plant recruitment, especially key species recruitment, is crucial in a succession process, and is the base of restoration ecology. There are various factors restrict plant recovery in degraded wetland ecosystems, such as seed limitation, physical stresses and interactions between species. Only the key limitations are overcome can the plants be recovered. In this study, plant recruitment on bare patches in a salt marsh via the facilitation of microtopographic structures was studied by field experiments. Since seeds can be dispersed by tidal waters, and can be entrapped in microtopographic structures to establish, limitation of these bare patches is not seed dispersal, but seed retention. Thus, more attention is paid on seed retention, rather than soil conditions and the interaction between species. Microtopographic structures can facilitate plant recruitment via seeds trapping, and this facilitation is relevant to the relative surface elevation differences (RSED) of microtopographic structures. With the increasing of RSED, more seeds can be entrapped and established. Moreover, RSED of microtopographic structures can be altered by the disturbance of tidal events, which will affect the facilitation in turn. With the increasing frequency of tidal disturbance, the relative surface elevation difference of microtopographic structure decreasing, which will decrease its facilitation effect. Our findings have important implications for plant restoration applications and suggest that constructing microtopographic structures with suitable relative surface elevation difference during seed dispersal to pre-emergence stages can be crucial to the success of plant recruitment in bare areas limited by seed retention.
Year: 2018