Biodiversity makes numerous contributions to a variety of ecosystem services (MA 2005). Regulating services (climate protection services, filtering functions, cooling services, water retention services) as well as cultural and social ecosystem services (services enhancing the quality of recreation, education, or appreciation of nature) are positively impacted by a rich biodiversity (SenStadtUm 2012).
To categorise this group of ecosystem services, habitat services are covered as „supporting service“ by the project Berlin's Peatlands and Climate Change. Habitat services are tied to site or location specific characteristics associated with the peatland habitat. The level to which peatland is undisturbed and in a natural state is critical for the provision of these services, and this is, therefore, the most significant aspect in their assessment.
The ecosystem service of biodiversity is designated by the project Berlin's Peatlands as a „Service“ to communicate and underscore its immediate positive effect on human well-being. After all, the tremendous value of biodiversity for human well-being is widely recognized within the scientific community. However, the term of „service“ is not ideally suited to get the message across to the public. In the public perception, the idea still persists that biodiversity only has value in and of itself rather than that it provides direct benefits to humankind.
The term „Habitat Services“ is considered to be well suited because the combination of biotic and abiotic site indicators characterizes the quality of a peatland ecosystem as habitat, which is being associated with a certain potential species diversity. This approach has a lot in common with the concept of the habitat types of the Fauna-Flora-Habitat Directive of the EEC (short Habitats Directive), where indicators regarding the site (e.g. water budget or overgrowing of shrubs) are combined with such regarding species diversity. Those for the site included such as water balance and land cover, or shrub overgrowth. By the InVEST Models, those ecosystem services linked to biodiversity, are referenced as „specific habitat quality“ (Holfeld & Rosenberg 2013). The basic idea to describe the quality of a habitat using a three-graded scale also corresponds to that used for the peatlands of Berlin here.
The advantage of assessing peatland habitats using biotope types is that necessary basic information, e.g. maps of biotope types is already available in most cases. This means that large areas can be covered and asessed. The result, however, depends on the scale of mapping, its accuracy and how up-to-date it is. As the method focusses on habitats, it is not possible to get information on species diversity. However, it is possible to describe specific site potentials for planning/management projects in which species-oriented targets will be defined. Compared to that, the project-oriented approach used for MoorFutures (Joosten et al. 2013) assesses „site-typical, or mire-typical biodiversity“ and requires defined „species types, groups or communities“ in order to predict development trends after a period of time within a defined project duration. The latter approach could be used as a complementary tool for the work on conservation projects, as it complements the proposed assessment of habitat services by its additional focus on target species or communities.