Palaeohydrology of the Gobi Desert

Funding

BMBF - Federal Ministry of Education and Research (2011-2014, 2016-2019)

This research work is integrated in the BMBF programs "CAME I: WTZ Central Asia – Monsoon Dynamics & Geo-Ecosystems" and "CAME II: Crossing Climatic Tipping Points - Consequences for Central Asia".

CAME I was supported through the bundle project "QUASI - Supra-regional signal pathways and long-time archives: Quaternary monsoon dynamics at the northern margin of the Tibetan Plateau". The successor bundle project in CAME II is "Q-TiP – Tipping Points of Lake Systems in the arid zone of Central Asia" with the subproject "Hydrological System of the Gaxun-Nur Basin", steered by the Free Universiity and AWI Potsdam.

Cooperation

• Eberhard Karls University Tübingen: Prof. Dr. Erwin Appel &  Prof.Dr. Todd Ehlers
• RWTH Aachen University: Prof. Dr. Frank Lehmkuhl , Dr. Georg Stauch, Prof. Dr. Klaus Reicherter
• Technical University Berlin: Prof. Dr. Dieter Scherer
• Ruprecht Karl University Heidelberg: Prof. Dr. Jörg Pross
• Free University Berlin: Dr. Kai Hartmann & Prof. Dr. Bernd Wünnemann
• Senckenberg Research Institute and Natural Museum Frankfurt: Prof. Dr. Volker Mosbrugger

Background

The northern foreland of the Tibetan Plateau with its endorheic basins plays a key role in the geological and palaeoenvironmental development of central Asia. The depositional environment is characterized by aeolian, fluvial, and lacustrine conditions. Sediment supply is also controlled by glacial dynamics and periglacial processes in the mountainous hinterland of the Qilian Shan. The mountains represent important sources for water supply to the agriculture belt of the adjacent Hexi Corridor and the endorheic basins. The sediments in the basins represent sediment repositories for dust transport over Central Asia and northern China and are directly connected with the Chinese Loess Plateau.

Water availability is of crucial importance for the arid areas in central Asia, influencing the living conditions on-site as well as the dust transport over the entire continent. Q-TiP is devoted to the recognition of climatic and non-climatic environmental factors that caused sudden status changes of hydrological systems in the past. Expected findings will provide the key for the understanding of modern environmental change and projections to the future. Therefore two main question must be answered:

• How had huge lake systems been preserved over a long-time period and what had caused tipping points that lead to their desiccation?
• How do tipping points influence the modern landscape with special regard to a recent and prospective climate change?

The methodic approach combines the anticipated inference of climate proxies from drill cores in combination with geomorphological surveys of the first project stage during CAME/QUASI and climate modeling. Our Work package "Hydrological System of the Gaxun-Nur Basin" is jointly operated between AWI Potsdam and the FU Berlin and is dedicated to the study of a long drill core from the Gaxun-Nur Basin, recovered during the first project stage (QUASI). The record covers the last 250 kyr at 230 m core length. Based on granulometric, palynologic, isotopic, geochemical and mineralogical analysis and a broad multivariate statistical approach, threshold responses of the hydrological system in the Gaxun Nur Basin and their causes in the past will be identified.