干旱区生态环境知识资源中心

The stabilization of sandy and loamy surfaces in semiarid and and areas by topsoil crusts protecting the soil against wind or runoff erosion is well known. Destruction of such crusts, often by overgrazing, can enhance erosion and desertification. Crust recovery does not depend purely on biotic components of the crust and vegetation. Mineral components in the initial surface stabilization process are often overlooked. The present study focuses on the relative importance of the biotic and mineral components in the process of topsoil crust recovery in a sandy desert area located in the northwestern Negev Desert of Israel. Observations of the initial crust and of the disturbed surface, in the field and under the scanning electron microscope, showed that the mineral components of the crust recovered more quickly than its biotic elements. The implications for the rehabilitation of the disturbed ecosystem are discussed. Copyright (C) 2002 John Wiley Sons, Ltd.