Sampling framework for the common breeding bird survey in Flanders, Belgium

<p>The sampling framework is based on 1 x 1 km UTM squares in Flanders. We determined the landscape composition of every square at the start of the survey in 2007. The Biological Valuation Map (Vriens et al., 2011) served as the basis for the landscape composition.</p><p>The file contains the following fields</p><ul><li>`UTM`: the UTM code of the square</li><li>`Stratum`: the stratum assigned to the square</li><li>`Oppervlakte`: the surface area of the square (in km²) contained within Flanders.</li><li>`Landbouw`: the fraction of aggriculture land use within `Oppervlakte`.</li><li>`Urbaan`: the fraction of urban land use within `Oppervlakte`.</li><li>`Bos`: the fraction of forest land use within `Oppervlakte`.</li><li>`Suburbaan`: the fraction of suburban land use within `Oppervlakte`.</li><li>`HeideDuin`: the fraction of heather or dunes land use within `Oppervlakte`.</li><li>`MoerasWater`: the fraction of heather or dunes land use within `Oppervlakte`.</li></ul><p>We distinguish six different strata based on the rules below.</p><ol><li>`Landbouw`: at least 80% `Landbouw`.</li><li>`Urbaan`: at least 80% `Urbaan`.</li><li>`Bos`: at least 80% `Bos`.</li><li>`Suburbaan`: at least 80% `Suburbaan`.</li><li>`Heide en duin`: at least 20% `HeideDuin`.</li><li>`Moeras en water`: at least 20% `MoerasWater`.</li></ol><p><strong>References</strong></p><p>Vriens L., Bosch H., De Knijf G., De Saeger S., Guelinckx R., Oosterlynck P., Van Hove M. &amp; Paelinckx D. (2011). De biologische waarderingskaart: biotopen en hun verspreiding in vlaanderen en het Brussels Hoofdstedelijk Gewest. Mededelingen van het Instituut voor Natuur- en Bosonderzoek, Nr. INBO.M.2011.1. Instituut voor Natuur- en Bosonderzoek, België.</p><p>&nbsp;</p>