A city-wide tree-planting programme allocates funding to the boroughs with the least canopy, and the allocation formula needs one number per borough from a source every borough accepts. The ESA WorldCover map is that source. The programme office wants the share of each borough under tree cover, on the borough polygons, ready to shade.
Return one feature per borough — the borough polygon — carrying:
nametree_pct — the share of the borough's land-cover pixels in class 10, percent, two decimalsCut the raster to each borough polygon and count. A pixel belongs to a borough when its centre is inside the polygon (rasterio's default; QGIS zonal statistics agrees). Return all 33, in EPSG:4326, least tree cover first.
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Zonal shares of a land-cover class per administrative unit are the standard input to canopy targets, heat-island programmes and biodiversity net-gain baselines.
7 scored, 0 informational
One feature per borough
15%Carries name and tree_pct
15%The greenest borough's share
15%The least-treed borough's share
15%Sum of the shares across all boroughs
23%Result is polygons
8%Submitted in EPSG:4326
8%