|Tidal flat dynamics|
de Blok, M. (2020). Tidal flat dynamics. MSc Thesis. NIOZ Royal Netherlands Institute for Sea Research: Yerseke. 26 pp.
The coast, the interface between the earth’s landmasses and its oceans, is of unparalleled beauty and one of the most essential ecosystems globally. Several important functions such as tourism and foraging areas for many bird- and fish species are provided by coastal ecosystems. Due to the wide range of environmental circumstances that occur near coastlines, a large range of landforms exists with highly variating characteristics in terms of morphological development (Christopherson & Birkeland, 2015). In this research, the primary focus lies towards the landforms that become regularly inundated; tidal flats, marshes and mangroves. These coastal ecosystems pose several other important ecosystem functions, including a critical primary production, high species richness and biodiversity and coastal protection (Tong et al., 2020). Being constantly subject to the diurnal cycle of the tides, tidal flats are the most dynamic of the coastal ecosystems, and a major part of the coastal defence (Leuven et al., 2019). Increasing anthropogenic pressures have impacted river basins and their estuaries worldwide through changes in the suspended sediment load carried by rivers (Murray et al., 2019). Both the development of sediment transport- and delivery to the estuary, as well as urban expansion at the estuaries themselves have resulted in diversification of tidal flat behaviour. Considering future expectations in the perspective of ongoing climate change, rising sea levels, enhanced subsidence and ongoing urban expansion at the cost of tidal areas and -dynamics, tidal flats will continue to be increasingly subject to environmental pressures (Ladd et al., 2019). These arguments of essentiality, lacking scientific knowledge and vulnerability reconfirm the need for a proper assessment tool. Identifying tidal flat development for a large number of estuaries worldwide may provide valuable insights into the response of tidal flats to these environmental and anthropogenic changes over the past decades. The essential question; whether tidal flats are sufficiently dynamic and resilient to cope with the rapidly changing conditions, will be one step closer to being answered. Recently, research groups such as Murray et al. (2019), have made progress regarding the calculation of global tidal flat extension, as derived from enormous collections of satellite imagery. However, Murray et al. (2019), only determined the changes in size, while the changes in morphology will provide more detailed information on how these tidal flats respond to their environments.