dragonflies, environmental indicators, dragonfly biotic index

Many dragonfly species are closely associated to specific environmental conditions. The close linkage to the specific conditions is a good presumption to indicator ability of species. Many studies point out that dragonflies do not reflect environmental pollution, but the general state of aquatic ecosystems. That is why dragonflies are used as indicators of environmental state of freshwater aquatic habitats. A very wide indicating potential has the dragonfly biotic index (DBI), which reflects the distribution, red list status and the sensitivity to habitat changes of each species regarding to environmental conditions. DBI represents a sophisticated tool for evaluating the quality of freshwater habitats.