Himalayan Lake Study - Reconstruction of the Holocene climatic history and recent anthropogenic changes in the southwestern Himalayas (Panjab and Kumaun Lakes)

点击翻译按钮获取中文摘要

The sedimentation in lakes is much more affected by regional tectonic and climatic processes than the sedimentation in the oceans. However, many lake studies have shown that regional climatic oscillations can be related to global climatic processes. Here we propose to investigate lake sediments from the southwestern Himalayas the climate of which is determined by the Asian monsoon circulation. The marine monsoon record from the northern Indian Ocean has been extensively studied during the last few years. Data from the continent are, however, very scarce. The aims of this investigation are (i) a reconstruction of the Holocene climatic history in the southwestern Himalayas based on sediment cores from the Mansar Lake as well as (ii) the investigation of the impact of anthropogenic activity on lake chemistry and sedimentation during the last 200-300 years in the Panjab and Kumaun Himalaya. Samples provided by our partner at the Panjab University, Chandigarh, India, consist of subsamples from a long core from the Mansar Lake spanning almost the complete Holocene record. Furthermore, samples from six short sediment cores from Himalayan lakes with different levels of anthropogenic pollution have been supplied (Renuka, Rewalsar, Nainital, Bhimtal, Naukuchiyatal and Sattal Lakes). Inorganic geochemical as well as biogeochemical investigations on these samples will provide information on the changes in the sources of clastic material, the weathering intensity, primary productivity and the organic matter source. The combination of these results will add to a reconstruction of the climatic history of the western Himalayas and will be compared to the information from the marine record of the northern Indian Ocean, the ice core record, and results from other lake studies.