ABSTRACT
At fi rst, the notion of diversity seems clear and intuitive. However, other terms have sometimes been used synonymously, such as variety, heterogeneity, variability, complexity, etc. At the scientifi c level these synonymous usages cause confusion and vagueness. Since the foundation of natural-resource sciences, experts from different disciplines have recognized the impressive global diversity surrounding them, regardless of whether their interest was in living organisms, rocks, landforms or soils. The increased diversities over larger spaces and areas can probably be traced back centuries, perhaps including prehistoric times, when fi rsthand knowledge of natural resources and their diversity was fundamental for survival. Thus, any search for the foundation of the diversity concept in any branch of natural sciences must be subjective, biased and the origin somewhat arbitrary.
