Field Observation of Saltmarsh-Edge Morphology and Associated Vegetation Characteristics in an Open-Coast Tidal Flat

Chen, L.; Zhou, Z.; Xu, F.; Möller, I., and Zhang, C.K., 2020. Field observation of saltmarsh-edge morphology and associated vegetation characteristics in an open-coast tidal flat. In: Malvárez, G. and Navas, F. (eds.), Global Coastal Issues of 2020. Journal of Coastal Research, Special Issue No. 95, pp. 412-416. Coconut Creek (Florida), ISSN 0749-0208. Saltmarshes are vulnerable morphological units, while their edges serve as an important indicator for regional sediment budget. The relation between three forms of saltmarsh edges and the vegetation characteristics was explored. Saltmarsh quadrats as well as their associated hydrodynamics were analyzed on the tidal flat of the Yancheng Nature Reserve in the middle Jiangsu coast, China. Results indicate that different marsh-edge morphologies were associated with different vegetation parameters, i.e., density, mean diameter, and dry biomass. These parameters showed different spatial variational trends and certain phase differences existed between these trends. However, the mean plant height presented a comparable spatial variational trend in different marsh-edge forms, indicating that the plant height was likely controlled by tidal range which was nearly the same in different sites. A transitional zone was defined between the smooth section and the cliff section, where the young seeding marsh showed a cyclic growth-erosion-regrowth behavior. Therefore, the hydrodynamic condition in this transitional area may be considered as a probe of the critical state between the cliff form and the smooth form.