QDGC

QDGC - Quarter Degree Grid Cells (or QDS - Quarter degree Squares) are a way of dividing the longitude latitude degree square cells into smaller squares, forming in effect a system of geocodes. Historically QDGC has been used in a lot of African atlases. Several African biodiversity projects uses QDGC, among which The atlas of Southern African Birds^[1] is the most prominent one. In 2009 a paper by Larsen et al. ^[2] describes the QDGC standard in detail.

^ HARRISON, J.A., ALLAN, D.G., UNDERHILL, L.G., HERREMANS, M., TREE, A.J., PARKER, V. & BROWN, C.J. (1997) The atlas of southern African birds. Vols 1 and 2, BirdLife South Africa, Johannesburg, South Africa.
^ Larsen, R.; Holmern, T.; Prager, S.D.; Maliti, H.; Røskaft, E. (2009). "Using the extended quarter degree grid cell system to unify mapping and sharing of biodiversity data". African Journal of Ecology. 47 (3): 382–392. doi:10.1111/j.1365-2028.2008.00997.x.

[1] HARRISON, J.A., ALLAN, D.G., UNDERHILL, L.G., HERREMANS, M., TREE, A.J., PARKER, V. & BROWN, C.J. (1997) The atlas of southern African birds. Vols 1 and 2, BirdLife South Africa, Johannesburg, South Africa.

[Larsen_et_al_2009-2] Larsen, R.; Holmern, T.; Prager, S.D.; Maliti, H.; Røskaft, E. (2009). "Using the extended quarter degree grid cell system to unify mapping and sharing of biodiversity data". African Journal of Ecology. 47 (3): 382–392. doi:10.1111/j.1365-2028.2008.00997.x.

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