RO-R-5: Land used for human settlements and transport infrastructure

The picture shows a large open ground area on a construction site. In the background, an excavator is standing on the area to the right of a mound of earth, and parts of an industrial hall can be seen to the left. Click to enlarge
Once soils are sealed by buildings, they are unable to provide important ecosystem services.
Source: Photograph: © Superingo / stock.adobe.com

2019 Monitoring Report on the German Strategy for Adaptation to Climate Change

Table of Contents

 

RO-R-5: Land used for human settlements and transport infrastructure

Based on the four-year average, the peak of land use for settlements and transport infrastructures occurred in 2000. Above all, there has been a slowdown in the growth in terms of settlement and open areas. It is true to say, however, that this growth has been increasing again over recent years. It must be borne in mind that the conversion processes required in terms of land registry in the ‘newly’ joined Länder have limited the informative value provided by land categories.

The stacked column graph shows the daily increase in hectares per day from 1997 to 2015 for building and open space, operational area excluding quarrying land with a quadratically increasing trend, recreational and cemetery area with a quadratically decreasing trend, and transport area with no trend.
RO-R-5: Land used for human settlements and transport infrastructure

The stacked column graph shows the daily increase in hectares per day from 1997 to 2015 for building and open space, operational area without quarrying land with a quadratically increasing trend, recreational and cemetery area with a quadratically decreasing trend, and transport area without a trend. Up to 2004, the category of building and open space, operational area without quarrying land clearly predominates, from 2005 to 2009 recreational and cemetery area. From 2013 to 2015, corrected data apply due to method changes in individual federal states. In 2016, due to regroupings between types of use, there is only a 4-year mean value from 2013 to 2016, which is not differentiated by category. In addition, the four-year moving average of the daily increase in settlement and transport area is plotted as a line. The value for 2016 is 60 hectares. The time series shows a significant downward trend.

Source: StBA (Sustainable development indicators)
 

Provident new land use also contributes to adaptation

A terrain that has not been built on, is unfragmented and free from urban sprawl is a limited and desirable resource which is much in demand and the object of competition among agriculture, forestry, developers, transport infrastructure, nature conservation, the exploitation of raw materials and the generation of energy. The designation of priority and restricted areas is a tool used by spatial planning in order to guide any new land use and to moderate various claims on utilisation. Last not least the intention is to conserve or further enhance ecosystem services important to humans and nature.

In connection with changing climatic conditions, ecosystem services address the potential of unsealed surfaces to allow the infiltration of precipitation and also – at times of flooding – to provide temporary retention. Alluvial meadows free from housing developments provide space for rivers and take the pressure off downstream areas of the river basin at times of flooding. In bioclimatically stressed spaces, the passage of fresh and cool air to residential areas is paramount. On the periphery of conurbations, air can cool off faster in the summer months above meadows and arable land than in residential areas. Air channels such as parts of open valleys transport the cool air to neighbouring residential areas thus mitigating any thermal stress. As far as agriculture and forestry are concerned, and also in respect of the harvesting of renewable raw materials, it is above all relevant to protect fertile soil and productive land in a sustainable way for the future. Moreover, animals and plants depend on open spaces and networked, unfragmented habitats and landscape structures for their survival and reproduction. If habitat conditions change as a result of climate change, fauna and flora are in need of functioning biotope networks enabling them to adapt.

These potentials for use or change of use for agricultural or forestry purposes are maintained or relatively easily restored if the new type of land use is, for example, the generation of renewable energy or nature conservation, whereas these potentials would be permanently lost, if the new land use were to involve developing the terrain for settlement or transport infrastructure or if it were to involve any form of mining such as large-scale quarrying projects. Using tools from its toolbox, spatial planning can reduce the amount of adverse effects from unsuitable types of land use; consequently this action can be seen as a general adaptation measure. At the same time, reducing any new land use is also one of the key sustainability objectives pursued by the Federal Government. The target is to reduce the daily new land use for the development of settlements and transport infrastructure by 2020 to 30 hectares, and by 2030 to less than 30 hectares (minus X). Since 2000 new land use has been declining. This can be attributed above all to a slowdown in growth regarding the development of settlement and open areas as well as factory or workshop areas with the exception of extraction land. This growth has diminished by half, and since 2005 it has been fluctuating between 30 and 40 hectares per day. At present, the level of activity in the building industry is rising again, especially in respect of space-saving multi-storey residential buildings, less so regarding the space-hungry construction of detached and semi-detached houses. Up until 2007, the increase in transport infrastructure remained largely consistent between 20 and 25 hectares per day, owing to the continued enhancement of the interurban roads network. Since 2008 this growth has slowed down: with approximately 11 hectares per day, 2012 reached the lowest level so far; however, in view of changes in the methodology underpinning spatial statistics, these statements are subject to major uncertainties. However, the strong increase in recreational and cemetery areas between 2003 and 2009, does not constitute an altogether real change in land use; in fact, this rise should be attributed to the conversion of official land registry methods, especially in the ’newly’ joined Länder of the Federal Republic, which the survey is based on. In other words, the real change in land use therefore tended to be lower than indicated by spatial statistics.

To what extent the tools employed by spatial planning have contributed to the overall slow-down in new land use is hard to tell from looking at spatial statistics. Actually, the reasons for subdued growth in new land use for settlement and transport infrastructures over recent years are considered to be related to the development of demographics and the economy. However, the sustainability goal aspired to in the run-up to 2020 seems rather hard to achieve, even if current development trends continue and despite the temporarily major influx of immigrants. Any additional efforts required to achieve provident land use will have to take account of potential impacts from climate change. An intensified development of settlements in an inward direction, that is to say, by means of land recycling or retro-densification, must not increase any existing bio-climatic stresses.

 

Interfaces

BAU-I-1: Heat stress in urban environments

WW-I-3: Floodwater

RO-R-6: Settlement use in flood-risk areas - case study

 

 

Objectives

Enhancing the infiltration potential of soils by reducing the amount of new land use and by supporting the renaturation and desealing of land (DAS, ch. 3.2.14)

Land use reduced to less than 30 hectares per day by 2030 (NHS 2016, Part C, II 11)83

Protective and provident handling of ground, reducing any additional use of areas for building purposes, giving priority to internal development (BauGB, § 1a (2))

Reducing any first-time utilisation of open spaces for settlement or transport infrastructure, in particular by means of quantified targets to reduce land use (ROG, § 2 (2) 6)

Non-renewable natural assets should be used in a provident and prudent manner. (BNatSchG, § 1 (3))

83 - Die Bundesregierung 2016: Deutsche Nachhaltigkeitsstrategie – Neuauflage 2016. Berlin, 258 S.
www.bundesregierung.de/resource/blob/975274/318676/3d30c6c2875a9a08d364620ab7916af6/2017-01-11-nachhaltigkeitsstrategie-data.pdf