Military land use and the impact on nature and landscape a study of Danish military areas 1900 - 2017

Military use of land for preparations for war, such as training areas, ranges and depots constitutes a special form of land use, as it is governed by different drivers and logic compared to the civil landscape. Several studies imply that the military use of land for training and maintenance purposes generates landscapes, with a positive effect on nature and biodiversity. This paper reports on a comprehensive study of military land holdings in Denmark between 1900 to present. The relationship between military land use and nature quality as well as biodiversity was studied on all known military sites larger than 10 hectares (N=113) covering a total of 38.576 hectares. For each military site, land use trajectories were identified based on interpretation of historical topographic maps. Additional spatial data were applied to assess the present land use and land cover composition as well as the content of biological diversity. Results suggest, that military activities, in general, generate landscapes with a land cover and land use composition different from the Danish landscape in general, which is dominated by agriculture and urban land use. This difference is also reflected by a relatively high biodiversity on military sites. The analysis of historical topographical maps also revealed six typical development trajectories for military sites. (1) conserving original marginal land (with high nature quality); (2) change from agriculture to nature or open areas; (3) afforestation of former marginal lands; (4) permanent and continues forest cover; (5) change from arable land or nature to build environment and (6) development into recreationalland. Interestingly, results also indicated that high nature quality and biodiversity on military sites, which originated from arable land. This suggests that military activities not only conserve nature and biodiversity but also create new valuable nature. However, some results also suggest that the benefitsfor nature are related to specifics types of military activity, such as maneuver grounds and ranges, while the positive impact of depots and technical installations are less significant or even negative