Standardized map of habitat types and regionally important biotopes in Flanders

<p>The&nbsp; <code>habitatmap_stdized.gpkg</code> file&nbsp;is a processed version of the&nbsp;<a href="https://www.vlaanderen.be/datavindplaats/catalogus/biologische-waarderingskaart-en-natura-2000-habitatkaart-toestand-2023">Natura 2000 habitat map of Flanders</a> (De Saeger et al., 2023; see also De Saeger et al. 2017). It contains all polygons with Natura 2000 habitat types or regional important biotopes (RIB). This file is used as a basis for designing monitoring schemes in Flanders.&nbsp;&nbsp;&nbsp;</p> <p>In the original habitat map, every polygon&nbsp;can consist of maximum 5 different types (habitat (sub)types and regionally important biotopes). This information is stored in the columns&nbsp; <code>HAB1</code>, <code>HAB2</code>,..., <code>HAB5</code> of the attribute table. The fraction of each type within the polygons is stored in the columns <code>PHAB1</code>, <code>PHAB2</code>, ..., <code>PHAB5</code>.</p> <p>The <code>habitatmap_stdized.gpkg</code> file is a GeoPackage that contains:</p> <ul> <li><code>habitatmap_polygons</code>: a spatial layer with every habitat map polygon that contains a Natura 2000 habitat or RIB&nbsp;type.</li> <li><code>habitatmap_types</code>: a table with information on the habitat and RIB types (HAB1, HAB2,..., HAB5) that occur within each polygon of&nbsp;<code>habitatmap_polygons.</code></li> </ul> <p>The processing of the habitatmap_types table included following adjustments:</p> <ul> <li>For some polygons the&nbsp;type is uncertain, and the type code in the raw habitatmap data source consists of 2 or 3 possible types, separated with a ','. The different possible types are split up and one row is created for each of them, with <code>phab</code> for each new row simply set to the original value of <code>phab</code>. The variable <code>certain</code> will be <code>FALSE</code> if the original type code consists of 2 or 3 possible&nbsp;types, and <code>TRUE</code> if only one type is provided.</li> <li>Some polygons contain both a standing water habitat type and <code>rbbmr</code>: <ul> <li><code>3130_rbbmr</code>,</li> <li><code>3140_rbbmr</code>,</li> <li><code>3150_rbbmr</code>, and</li> <li><code>3160_rbbmr</code>.</li> </ul> </li> <li>Since <code>habitatmap_stdized_2020_v1</code>, the two types <code>31xx</code> and <code>rbbmr</code> are split up and one row is created for each of them, with <code>phab</code> for each new row simply set to the original value of <code>phab</code>. The variable certain in this case will be <code>TRUE</code> for both types.</li> <li>After those steps, a given polygon could contain the same type with the same value for <code>certain</code> repeated several times, e.g. when <code>31xx_rbbmr</code> is present with <code>phab</code> = yy% and <code>31xx</code> is present with <code>phab</code> = zz%. In that case the rows with the same <code>polygon_id</code>, <code>type</code> and <code>certain</code> were gathered into one row and the respective phab values were added up.</li> </ul> <p>The R-code for creating the <code>habitatmap_stdized</code> data source can be found&nbsp;in the GitHub repository&nbsp;<a href="https://github.com/inbo/n2khab-preprocessing/tree/abf596e/src/generate_habitatmap_stdized">'n2khab-preprocessing' at commit abf596e</a>.</p> <p>A reading function to return the data source in a standardized way into the R environment&nbsp;is provided by the R-package&nbsp;<a href="https://github.com/inbo/n2khab">n2khab</a>.</p> <p>Attributes of <code>habitatmap_polygons</code>:</p> <ul> <li><code>polygon_id</code></li> <li><code>description_orig</code>: polygon description based on the original type codes in the raw habitatmap&nbsp;</li> </ul> <p>Attributes of <code>habitatmap_types</code>:</p> <ul> <li><code>polygon_id</code></li> <li><code>type</code>: the interpreted habitat or RIB type</li> <li><code>certain</code>: <code>TRUE</code> when type is certain and <code>FALSE</code> when type is uncertain</li> <li><code>code_orig</code>: original type code in raw habitatmap</li> <li><code>phab</code>: proportion of polygon covered by type, as a percentage.</li> </ul> <p>Since version <code>habitatmap_stdized_2020_v1</code>, rows are unique only by the combination of the <code>polygon_id</code>, <code>type</code> and <code>certain</code> columns.</p>