BMBF-Förderschwerpunkt "Sustainable Landmanagement"

The expansion of settlements and the settlement structure have a considerable impact on climate change. A decentralised and compact settlement structure, which is nevertheless green and geared to expanding the public transport infrastructure, is said to have an important share in reducing CO2 emissions especially from transport and domestic fuel. However, compact and qualitatively concentrated settlement structures also bring about resilience and, thus, helping areas to proactively adapt to the inevitable impacts of climate change.

But the expansion of settlements and the related dispersion and fragmentation of settlements also have a direct impact on open areas especially used as agricultural land. These trends indirectly reduce options for a climate-proof land-use management. Its impact on climate protection and adaptation to climate change is again impaired by urban restructuring activities including demolition, land recycling and unsealing activities as well as by the transformation of urban-like landscapes such as conversion areas in the open land, open-cast mining landscapes or renewable energy production areas.

Aims:

The subproject “Land-Use Scenario 2030” is oriented towards the built-up parts of landscapes, especially settlement areas, and focuses on scenarios of their future development. The latter are to calculate the amount of future settlement and transport areas, thus also defining the amount of remaining open areas, which again provides the basis for other CC-LandStraD subprojects. Furthermore the scenarios shall help to identify strategies for a CO2-reducing settlements development.

The objective of the subproject is to develop a land-use scenario 2030. A trend forecast (business as usual) is used to identify the land use expected as well as scenarios for 2030. The subproject “Land-Use Scenario 2030” thus mainly serves to forecast and regionalise the development of settlement and transport areas in Germany. The results will be examined in terms of their climatic effect and combined with the results of the other subprojects.

First of all, a trend forecast will be produced to develop the land-use scenarios 2030. A trend forecast is a likely future development that results from historic development, adopted policies and expert judgment. Other development scenarios, which are based on different economic, political and demographic estimates, are to illustrate the variety of possible development trends of land use in 2030.

The expansion of settlement and transport areas in Germany nearly exclusively goes along with the rezoning of former agricultural areas. The calculations are to demonstrate how much (agricultural) land tends to be required by additional settlement and transport areas according to each scenario. The climate effect of the scenarios will then be evaluated. It will also be necessary to check the possibility of bringing the estimated land use into line with the climate-optimised land use.

Modelling framework – settlement and transport areas

In a first step, projections of regional claims for every single land use type are developed (e.g. settlement and transport area, agriculture, forest). The claims for urban land use types are estimated by the model PANTA RHEI REGIO that was developed by the GWS Osnabrück. The model estimates the settlement and transport area, differentiated by urban land use type (residential, industry / commercial, transport area, leisure facilities, urban green areas), based on the historic trends of settlement structure, demographic and economic development on Nuts3 level for the year 2030. The demographic development is provided by the population and household forecast of the BBSR.

In a second step, these results serve as input information for the land use change model Land Use Scanner. It is a GIS based simulation model where qualitatively formulated scenarios are underlaid quantitatively and are explicitly simulated spatially. On the basis of spatial land use data, the spatial planning and further location factors such as relief or accessibility the local suitability of individual land uses will be assessed. Regional spatial demands and local suitability are ultimately integrated in the Land Use Scanner. The model simulates the explicit land use changes spatially, based on the microeconomic theory of land rents. With the help of further land use patterns, the effectiveness of single simulated adaptation methods can ultimately be assessed