Invertebrates of Geothermally Influenced Aquatic and Terrestrial Ecosystems: Longitudinal and Lateral Linkages

Abstract

The landscape and water bodies overlying geothermal areas are characterised by zones of high temperature, high ion concentrations, unusual pH conditions, and the influence of geothermal activity on these waters is also often highly variable between and within each system. The biodiversity of geothermally influenced aquatic ecosystems is typically low but little is known of the fauna of associated terrestrial ecosystems. As part of studies investigating the food web linkages between geothermally influenced aquatic and terrestrial ecosystems, the longitudinal distribution of invertebrates in two geothermal streams has been quantified. Species counts varied little downstream but abundance varied. Studies of ground-dwelling invertebrates at a single geothermal site showed a variety of species transient within the geothermally influenced zones alongside streams and varied with distance from the waterway. Most invertebrates found were commonly-occurring types.