The indicator is based on the method of Effective Mesh Size (meff, Jaeger 2000). The effective mesh size (meff) can be interpreted as the area that is accessible when starting a movement at a randomly chosen point inside a landscape without encountering a physical barrier (hereafter a Fragmentation Geometry. The index Effective Mesh Density (seff) is a measure of landscape fragmentation, i.e. the degree to which movement between different parts of the landscape is interrupted by FGs. The seffvalue is calculated as 1000/meff, hence number of meshes per 1000 km2.1km2cell size regular grid is used as reporting units.Please note that the size of the reporting unit does not have an effect on the indicator. For a detailed methodology, please consult the indicator fact sheet.