Ontwikkelen en toepassen van een methodiek voor de vertaling van de Belgische bodemclassificatie van de kustpolders naar het internationale WRB systeem en generaliseren van de WRB-bodemkaart voor gans Vlaanderen naar het 1 : 250 000 schaalniveau The soil map of the Flemish region converted to the 3 rd edition of the World Reference Base for soil resources Stefaan Dondeyne, Laura Vanierschot, Roger Langohr Eric Van Ranst and Jozef Deckers Oct. 2014 Opdracht van de Vlaamse Overheid Bestek nr. BOD/STUD/2013/01 Contents Contents............................................................................................................................................................3 Acknowledgement ...........................................................................................................................................5 Abstract............................................................................................................................................................7 Samenvatting ...................................................................................................................................................9 1. Background and objectives.......................................................................................................................11 2. The soil map of Belgium............................................................................................................................12 2.1 The soil survey project..........................................................................................................................12 2.2 Legend of the soil map of Belgium........................................................................................................14 The inland parts .....................................................................................................................................14 Legend of the polders ............................................................................................................................17 3. The World Reference Base for Soil Resources........................................................................................20 3.1 WRB as a classification system.............................................................................................................20 Example .................................................................................................................................................22 3.2 WRB for constructing map legends.......................................................................................................25 3.3 Characteristics of the Reference Soil groups of the Flemish region.....................................................27 Histosols ................................................................................................................................................28 Anthrosols..............................................................................................................................................29 Technosols .............................................................................................................................................30 Leptosols................................................................................................................................................32 Gleysols .................................................................................................................................................32 Podzols...................................................................................................................................................33 Planosols................................................................................................................................................35 Stagnosols..............................................................................................................................................36 Phaeozems .............................................................................................................................................38 Umbrisols...............................................................................................................................................39 Retisols ..................................................................................................................................................40 Alisols and Luvisols...............................................................................................................................42 Cambisols ..............................................................................................................................................44 Arenosols ...............................................................................................................................................47 Fluvisols.................................................................................................................................................48 Regosols.................................................................................................................................................48 4. General approach......................................................................................................................................50 4.1 Soil variability per soil district .............................................................................................................50 4.2 Use of legacy soil profile data ..............................................................................................................52 4.3 Heuristic rules ......................................................................................................................................53 Identification of Reference Soil Groups ................................................................................................53 Qualifiers for drainage status.................................................................................................................55 Variations in parent material, and/or occurrence of substratum ............................................................55 Qualifiers pertaining to base saturation .................................................................................................57 Qualifiers pertaining to soil texture .......................................................................................................58 4.4 Convertion of the mapping units of the coastal polders and dunes ......................................................60 5. Conversion to WRB units .........................................................................................................................62 5.1 Classification of soil profiles ................................................................................................................62 5.2 File attribute table of the conversion....................................................................................................63 5.3 Map legends and soil classification......................................................................................................65 Map legends...........................................................................................................................................65 Soil classification...................................................................................................................................67 5.4 Supplementary qualifiers ......................................................................................................................69 Soil map of the Flemish region converted to 3 rd edition of WRB 5.5 Generalisation to 1 : 250 000 scale map ..............................................................................................70 6. Discussion and conclusions .......................................................................................................................72 6.1 General considerations.........................................................................................................................72 6.2 Observations and encountered difficulties............................................................................................73 Soils with profile development "..h"......................................................................................................73 Errors in the digital soil map..................................................................................................................74 6.3 Limitations of the current maps............................................................................................................78 Nature of legacy data .............................................................................................................................79 Cartographic inconsistency....................................................................................................................79 Accuracy of the original maps ...............................................................................................................80 Land-use changes...................................................................................................................................82 References ......................................................................................................................................................83 Annexes ..........................................................................................................................................................85