(This textual content was kindly contributed on our request by Dr. Hans-Ulrich Rösner, WWF Germany, relating to the German expertise with embankments in tidal flats.)
Dr. Hans-Ulrich Rösner, WWF Germany:
Initially, I wish to emphasize that I don’t want to touch upon actions in Korea, as I can’t adequately assess the native state of affairs from afar. Nevertheless, I can provide some insights into how we might consider comparable measures within the context of the German-Dutch-Danish Wadden Sea.
The constructions proven within the photographs are generally known as Lahnungen (sea embankments), which have been traditionally used on a big scale within the Wadden Sea to calm tidal currents and facilitate land reclamation. By lowering the circulate of water, these constructions enable sediment to build up extra quickly, enabling the formation – or accelerated formation – of saltmarshes, which might later be embanked by dykes. Luckily, the development of such embankments has been prohibited within the Wadden Sea for a number of many years. Nevertheless, even right now, Lahnungen are nonetheless constructed or maintained immediately in entrance of dykes – not for the aim of land reclamation anymore, however to advertise the event of a saltmarsh or ‘foreshore’ that serves to dampen wave vitality and thereby defend the dyke from erosion.
The {photograph} reveals such a case within the Wadden Sea. It additionally illustrates that, regardless of the presence of Lahnungen, the hydrodynamic situations at that location don’t, underneath real-world situations, allow the pure improvement of saltmarshes.
It’s value noting that the constructions depicted within the Korean context differ considerably from these historically used within the Wadden Sea. In Korea, the Lahnungen look like crammed with stones, whereas within the Wadden Sea they’re usually crammed with brushwood. This methodology is extra ecologically applicable for the Wadden Sea, given the absence of a stony shoreline within the area.
Importantly, the development or upkeep of Lahnungen at a larger distance from the dyke is often not permitted within the Wadden Sea, as in these extra seaward areas such constructions not serve a significant operate for coastal defence, thus nature conservation has precedence.
From a conservation perspective, I might typically advise in opposition to the synthetic creation of salt marshes within the Wadden Sea on the expense of intertidal mudflats. The first conservation goal for the Wadden Sea is to permit pure processes to proceed so far as attainable in an undisturbed approach. Accordingly, it isn’t applicable to put a better worth on saltmarshes than on mudflats and to create them artificially. Pure dynamics within the Wadden Sea outcome within the pure formation of salt marshes in some areas and their erosion in others, giving approach to mudflats. This ever-changing panorama is a key facet of the Wadden Sea’s Excellent Common Worth (OUV) and kinds the inspiration for its recognition as a UNESCO World Heritage Web site.
As regards to birdlife, a large-scale transformation of mudflats into salt marshes might cut back accessible feeding grounds for a lot of species. Provided that meals sources within the Wadden Sea would possibly virtually totally be utilized by waders and waterfowl, such habitat loss might probably have antagonistic results on chook populations.
