Green volume number
Green volume number ( GVZ for short ) is a term from landscape planning and describes the product of the area covered by vegetation (e.g. the area of a forest) and the height of the vegetation.
In 1984 the Hamburg environmental authority published “Expertise - Values for Landscape and Urban Development Planning” for the first time the possibilities for establishing a so-called soil function number and green volume number were examined with the aim of establishing these as norms in spatial planning.
relevance
The number of green spaces is relevant as a guideline for setting urban climatic quality goals with regard to air humidity , as this is not only influenced by the climate factor sealing (determined by the degree of sealing ), but also by vegetation. The decisive factor here is not the area of the vegetation, but its surface, as it regulates the amount of moisture-increasing evapotranspiration . The green volume number is an attempt to include the vegetation surface, which is otherwise difficult to determine, as a measure of the planning.
Examples
- A wooded area with a floor area of 100 m² and a total height of 8 m has a green volume of 800 m³
- A meadow with a floor area of 100 m² and a total height of 0.10 m has a green volume of 10 m³
literature
- M. Großmann, W. Pohl, HD Schulze: Green volume number and soil function number in landscape and urban development planning , publications of the authority for district affairs, nature conservation and environmental design, volume 9, Hamburg, 1983