Alternative area-perimeter ratios for measurement of 2D shape compactness of habitats

摘要

Area-perimeter ratios are often used to quantify 2D shape compactness. Shape compactness is of main importance to evaluate the effect of external disturbance on natural habitats. Reference values (Amin(p), Amax(p), Pmin(a), Pmax(a)) for area (A) and perimeter (P) are defined and proven. The calculation of these reference values is based on the characteristics of the object studied and on pixel geometry. The cases for 4- and 8-connectivity are discussed. Using these references, alternative area-perimeter ratios are composed. Examples are elaborated to illustrate the use of the indices and their performance.