## 3 Results  
### Hitelmoor and Its Coast 1980-2040: Comparative Expert Assessments  
The Hitelmoor and its coast were assessed in four scenarios representing the situation in these years: 1980 (traditional coastal protection and pasture farming), 2000 (traditional coastal protection and partial rewetting), 2020 (narrow coast and extensive rewetting) and 2040 (future coastal realignment and occasional flooding by the sea) (Figure 2). We used 1980 as the baseline scenario and the other years were compared to it (Figure 5). Figure 5: Comparative ecosystem service assessment of the four scenarios addressing Hitelmoor and its coast. Compared are the baseline scenario 1980 with the scenarios for the years 2000, 2020 and 2040. A score of 3 indicates a high increase (green) and \(-3\) a high decrease (red) in ecosystem service provision compared to 1980. The scores for the relative importance of the ecosystem services (grey) range from 0 (irrelevant) to 8 (very important). Shown are median, minimum and maximum scores based on 10 involved experts. The median scores for the relative importance of every ecosystem service indicate that provisioning ecosystem services in general were perceived as less important compared to regulating and cultural ecosystem services. The importance among the single ecosystem services varies very much, depending on the relevance, for the topic of flooding and moor restoration. However, the minimum and maximum scores for the relevance vary strongly among the experts. Practically every ecosystem service shows this variability and was by some perceived as important/very important and by others as of low relevance. Between 1980 and 2040, the median scores for nearly all ecosystem services show a steady increase or decrease. The exception is freshwater for drinking purposes, which only shows a decrease in the last scenario because of saltwater intrusion. Over the 60 years of development, the provisioning services show a diverse pattern with services increasing and others decreasing, resulting in a slight overall decrease. For the regulating services, a strong increase is assumed, with one exception: the control of erosion rates. The cultural services show strong increases in service provision. A comparison between 1980, representing an agricultural system, with the year 2040, the system in a natural state, shows that regulating as well as cultural services strongly benefit from renaturation. The strongest absolute changes in ecosystem service provision take place between 2000 and 2020 with the rewetting of the area. This is true for the regulating as well as for the cultural ecosystem services. While the increase in regulating ecosystem service provision meets the expectations, the assumed strong increase in cultural service is in contrast to the expectations of locals before the renaturation. Several locals expressed the opinion that the renaturation would be a threat to local tourism and considered it as not beneficial. These results suggest that an ES assessment may provide a more comprehensive view on consequences of measures and increase their acceptance. The minimum and maximum scores for many single ecosystem services differ strongly. For the control of erosion rates, coastal protection and freshwater purification, the minimum scores were \(-3\) and the maximum \(+3\). For most other ecosystem services, a significant variability among experts' scores is visible too. This reflects strong differences in the perception of the restoration consequences among the experts. To obtain better insight into the reasons, the experts were interviewed about the context for their scorings. Some of the experts explained that their scores were strongly based on the historic and actual use of the H\(\ddot{\text{u}}\)telmoor, i.e., the ecosystem service flow, while others scored the site's potential to provide services. Another reason for the score variability resulted from misunderstandings and inaccuracies in the definition of the scenarios and/or the provided ecosystem service description/definition.