Bioindicator beetles and plants in desertified and eroded lands in Turkey

Abstract

The xerophilous vegetation with characteristic insect assemblages is described in the main agricultural regions and native landscapes of Turkey. Long term intensive investigations documented vast biotic degradation of soil and vegetation (commonly referred to as desertification) by overgrazing, construction, recreation etc. Two main types of xeric landscape are under investigation: 1) natural highly specific deserts, semi-deserts, dry mountain slopes and screes; and 2) anthropogenic, newly emerged, floristically impoverished desertified areas. The presence of a multi-species insect assemblage on a xerophilous plant in certain area testifies its indigenous nature, whereas the absence of the specific consortium suggests recent plant invasion. The examples of the first case are the consortia of 3–6 species of Coleoptera, mainly Buprestidae, Chrysomelidae, and Curculionoidea, on some Apiaceae, Asteraceae, Brassicaceae, Chenopodiaceae, Ephedraceae (Ephedra spp.) and Polygonaceae (Calligonum polygonoides L.). Extreme examples of anthropogenic vegetation are overgrazed wormwood steppe and semidesert which lack usually diversified coleopterous consortia, including the most characteristic of this landscape, e.g., tenebrionids, and orthopterans. Rapid disappearance of the xerophilous complexes from the extraordinarily diversified and largely uninventoried Turkish biota makes preservation of the endangered plant and animal assemblages in different climatic zones of Turkey an urgent task.