Gesamtabundungsfähigkeit

Gesamtabundung, literally “total abundance” in German, is a term used in ecology to denote the total number of individual organisms of all species within a defined sampling unit—such as a plot, quadrat, or survey area. It provides a measure of community size and is commonly used alongside species richness and evenness to describe community structure. In many contexts, Gesamtabundung is referred to as total abundance or simply abundance, and it is distinct from relative abundance, which expresses the proportion of individuals of each species within the total.

Measuring Gesamtabundung typically involves counting all individuals observed within the sampling unit, or estimating this total when complete counts are impractical. In small or sessile communities (plants, stationary invertebrates), direct counts in fixed areas are feasible. For mobile or cryptic organisms, researchers use standardized sampling effort, replication, or models (capture-recapture, removal methods, occupancy modelling) to estimate total abundance. Data are often standardized by area, time, or effort to allow comparisons across sites or time.

Interpretation: A higher Gesamtabundung indicates a larger or denser community, but it does not convey how individuals are distributed among species. Two communities can have the same total abundance but very different species richness and evenness. Therefore, Gesamtabundung is most informative when interpreted alongside other metrics such as species richness, evenness, and diversity indices (e.g., Shannon, Simpson). Limitations include detection probability, observer bias, and sampling bias.