Added soil map section to GIS docs

CHANGELOG.md

@@ -8,11 +8,28 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [1.0.0] - in planning
 
-*Aim: 3 species, 2 crop growth models, farm model, GAEC scenarios, experimental analysis*
+*Aim: 4 species, 2 crop growth models, farm model, GAEC scenarios, experimental analysis*
 
 *Plan: decouple CairoMakie (#81), fix & test ALMaSS, set up first experiments*
 
-## [0.6.0]
+## [0.6.1] - unreleased
+
+*Plan: add soil maps, update GIS documentation, add more regions*
+
+### Added
+
+### Changed
+
+- added soil map section to GIS docs
+
+### Deprecated
+
+### Removed
+
+### Fixed
+
+
+## [0.6.0] - 13-01-2025
 
 **This point release re-implements the ALMaSS crop model**
 

docs/src/gis.md

 # Maps and weather data
 
-Persefone currently requires two separate map input files: one for land cover,
-the other for field geometry. Additionally, a weather input file is needed. 
-This documents describe how to obtain and process the data needed for each 
-of these.
+Persefone.jl requires three map input files: one for land cover, one for
+for field geometries, and one for soil types. Additionally, a weather input 
+file is needed. This documents describe how to obtain and process the data 
+needed for each of these.
 
 ## Land cover maps
 
@@ -72,6 +72,17 @@ the advanced parameters, set the output data type to `UInt32`. Finally, enter an
 output file name and run. The resulting TIF file can be passed to Persefone
 as the `farmfieldmap` parameter.
 
+## Soil data
+
+Soil data for Germany is provided by the Bundesanstalt für Geowissenschaften und
+Rohstoffe in form of the [Bodenatlas](https://bodenatlas.bgr.de/). This provides
+a (coarse, but for our purposes sufficient) map of the distribution of the basic
+soil types such as clay, silt, sand, and loam.
+
+To create the Persefone input file, you need crop this national map to the same 
+region as the other maps, then rasterise it (see instructions in the last paragraph
+of the previous section).
+
 ## Weather data
 
 Currently, Persefone uses historical weather data from the closes weather station