1. Land-use

Land-use describes the type of land that covers the surface. It is important to establish deposition velocities, in particular the uptake rate and the surface roughness. Also it is required to determine the biogenic emission fluxes, such as isoprene and terpene emissions from forests.

Land use and land cover are also important for future calculations of NO-soil emissions and wind blown dust and agricultural emissions from ploughing etc

The land-use data set that is used in the model is the so-called PELINDA data-base (de Boer et al., 2000). The NOAA AVHRR NDVI monthly maximum value composites are the main data source for the land cover classification. The 1997 composites have been used. The land cover categories are listed in Table 9.1.

Table 9.1 Land use classes used in Pelinda (de Boer et al., 2000)

urban area

arable land

irrigated arable land

permanent crops

pastures

natural grassland

shrubs and herbs

coniferous forest

mixed forest

deciduous forest

bare soil

permanent ice and snow

wetlands

inland water

sea

The PELINDA data base has a resolution of approximately 1x1 km. This is converted into a database on the LOTOS-EUROS grid. Each grid is characterised by the fraction of land-use in that particular grid cell. A grid cell is not typified by one land-use category but is often a combination of several categories.

For European Russia a comparison was made with land-use databases from Russian sources and it was decided to use the Russian data base (Stolbovoi and McCallum, 2002)

To apply the EDACS system for dry deposition we have adapted the land use data used by LOTOS-EUROS, since DEPAC only uses a subset of the land use categories. The conversion of these land use classes is not trivial, and it needs further attention. The conversions we made are listed in Table 9.2.

Table 9.2 Conversion of Land use categories from Pelinda to DEPAC

DEPAC	Pelinda database
Grass	Pastures + natural grassland + shrubs and herbs
Arable	Arable land + irrigated arable land
Permanent crops	permanent crops
Coniferous forest	Coniferous forest + 0.5 Mixed forest
Deciduous forest	Deciduous forest + 0.5 Mixed forest
Water	inland water + sea + wetlands + snow or ice
Urban	Urban area
Other	Bare soil
Desert	0.0

As has been mentioned under biogenic emissions, recently in the UBA project a new land use data base has been made based upon CORINE/Smiatek.

Because the CORINE land use data base has an official status, the so-called Corine/Phare land cover data from EEA, this land use data base will be incorporated into the LOTOS-EUROS model in the near future