SalFar framework on salinization processes: A comparison of salinization processes across the North Sea Region

The following text discusses the manifold processes that create or aggravate saline conditions in the North Sea Region. To clarify, this text focusses on the underlying ecological processes and the socio-economical or environmental drivers of salinization. The text does not address the subsequent saline conditions, equally diverse throughout the North Sea Region. For more information about the diversity in saline conditions across the North Sea Region we refer to the SalFar baseline study (WP3).

It is important to clarify that this text focuses exclusively on salinization processes in the North Sea Region. Other researchers have developed a framework for all processes that effect the coastal aquifer. For example, Oude Essink (2001) defines six categories that have an impact of the coastal aquifer, and as a result, six categories that influence the occurrence of salinization (see figure 1). While this framework is very comprehensive, it does not facilitate the discussion amongst the SalFar partners since the six-fold categorization is simply too complex. It is not suited for quick comparison between the various coastal areas of the North Sea Region.

Recently Daliakopoulos et al. (2016) reviewed the academic literature on salinization in Europe, and subsequently constructed an all-encompassing framework on salinization processes. They delineate two main categories of salinization processes: primary and secondary salinization (see figure 2). The first category, primary salinization, comprises all natural salinization processes, including physical or chemical weathering and transport from parent material, geological deposits or groundwater. Secundary salinization, on the other hand, results from human interventions, mainly irrigation with saline water or other ill-suited irrigation practices often coupled with poor drainage conditions. In the SalFar project we didn’t opt to make use of this framework as it is not specific to coastal regions. Moreover, the division is too extensive and in many coastal regions there is a complex interaction of natural and human-driven salinization processes.

Finally, Manca et al. (2015) define eight different types of salinization in their study of the Litorale Romano Natural Reserve. Similar to Daliakopoulos et al. (2016), Manca et al. (2015) divided eight types into a set of primary (natural) salinization processes and a set of secondary (anthropogenic) salinization processes. Equally, this eight-fold categorization of salinization processes is too fine-coarse in order to facilitate quick cross-region comparison in the SalFar project.
This report constructs an easily readable framework on salinization process in the North Sea Region. It aims to facilitate quick cross-region comparison.