COMPARISON OF TECHNIQUES DESCRIBING SCLEROBIONT ABUNDANCE AND DISTRIBUTION ON SHELLY SUBSTRATES

摘要

Patterns of sclerobiont encrustation constitute important data in studies of paleosynecology and autecology, yet methods used to collect this information are not standardized. The variation among different methods may be attributed to the need for uniquely designed methods applied to address a specific question. As a result, comparisons between sclerobiont studies are cumbersome, results are sometimes contradictory, and the interpretive value among published results is low. A comparison of techniques commonly used for computing sclerobiont abundance and distribution upon host substrates revealed that the simplest measure of abundance, numerical abundance, under-reported large colonial organisms and over-reported small colonial and solitary organisms when compared to calculated baseline values obtained from digitized photos in ArcGIS. Spatial abundance methods, also examined, show areal percent coverage estimation over-reports total encrustation, but not substantially.