The map of actual water erosion risk in Poland
METHODS / RESULTS
Methods and results
The first stage of the project, which has been finished recently assumed estimation of qualitative indicators of PWER (Potential Water Erosion Risk) and AWER (Actual Water Erosion Risk) indicators. These two indicators have been developed in our research team some 20 years ago and implemented in Polish legal regulations regarding soil protection agains water erosion and used in policy support till present.
A few words about PWER indicator. In late '80 the team has developed
a country-wide map od PWER indicator. It was a huge work, done on analogue
maps. With growing appearance of GIS our host Institute became a pioneer
within that wield in Poland. In result of one of GIS related projects
we have deigitized the PWER map, which became a part of AgroGIS application.
The PWER indicator represents a potential erosion risk and bases upon
three data layers: soil suscebility to erosion, terrain's slope and average
annual precipitation while the AWER indicator consists also from land
use and land managament information. Since there was no reliable enough
spatial informaiton layer on land use in Poland, the AWER indicator has
been used only in local case studies (i.e. Grodarz
Erosion COntrol programme)
Within that projects we have re-estimated the PWER map basing on avaiable digital datasets: 90m SRTM DEm, 1:100.000 vector soil map and a grid of average annual rainfall. The results show substancial differences between PWER done on analogue and digital data. We think, that the main difference is caused by the huge distance between source data: analogue PWER was based on 1:25.000 topographical maps - which gives a reference grid resolution of about 25-30mm, while the resolution of SRTM DEM equals 90m, meaning 9 times less detailed reflection on detail of terrain's relief.
The detailed methodology and results are presented in our recent publication in English which should appear before August 2007: Wawer R., Nowocień E., 2007. DIGITAL MAP OF ACTUAL WATER EROSION RISK IN POLAND. A QUALITATIVE, VECTOR BASED APPROACH. Polish Journal of Environmental Studies. forthcoming
The synthesis of the results, covering also data quality issue, will be published very soon in form of a monography in both: Polish and English.
The map of AWER indicator will be avauable for wider public in form of an UMN MapServer WebGIS application.