干旱区生态环境知识资源中心

This paper presents a synthesis of results from investigations into palaeolimnology and dune chronology in the Manga Grasslands and adjacent areas of NE Nigeria, in order to reconstruct the evolution of this semi-arid landscape since the late glacial. A marked wet phase gave way to a Fall in lake levels during the late glacial. Dune emplacement was active at this time to the south of the Manga Grasslands, but seems to have been absent from the grasslands themselves. Wet conditions prevailed during much of the early to mid-Holocene, accompanied by periods of significant barchanoid dune reactivation. A marked deterioration in climate and vegetation commenced around 4.1 ka sp, leading to the formation of the present-day semi-arid landscape. The data suggest that there have been major changes in humidity in this part of Subsaharan West Africa during the late glacial to Holocene and that the relationship between changes in precipitation and aeolian activity is complex.