Bakhira Lake Sediments and Water Resource Management in the Central Ganga Plain

Context

• Recently, researchers of Birbal Sahni Institute of Palaeosciences, under the Department of Science & Technology (DST), analysed nearly 25,000-year-old sediments from Bakhira Lake, Uttar Pradesh, to reconstruct monsoon, hydrology, erosion and sediment-transport variability in the Central Ganga Plain.

About the Research

• Researchers studied a ~25,000-year sediment sequence from Bakhira Lake and used seven AMS radiocarbon dates to establish the age of the sediment layers.
• Researchers analysed magnetic properties of the sediments to identify changes in hydrology, erosion, sediment input and weathering, and combined these with sedimentological, geochemical and clay-mineralogical data from the same core.

About Seven AMS Radiocarbon Dates

• AMS (Accelerator Mass Spectrometry) is a highly sensitive technique used for radiocarbon (Carbon-14) dating.
• It measures the remaining Carbon-14 in organic material to determine its age.
• In this study, seven AMS radiocarbon dates established when different Bakhira Lake sediment layers were deposited.
• These dates provided a reliable ~25,000-year chronological framework, allowing researchers to link sediment changes with past climate and Indian Summer Monsoon variability.

Geographical and Ecological Profile of Bakhira Lake

• Bakhira Lake is located in Sant Kabir Nagar, Uttar Pradesh, within the Ghaghara–Rapti alluvial system.
• Bakhira Lake is a perennial oxbow/floodplain wetland formed by the migration and subsequent cut-off of the Rapti River.
• It is one of Uttar Pradesh’s largest natural wetlands, it was designated a Ramsar Site in 2022.
• Its floodplain–lacustrine setting enables continuous sediment accumulation from the lake and surrounding catchment, preserving signals of monsoon-driven runoff, weathering and sediment transport.

Conclusion

• The Bakhira Lake sediment study provides a nearly 25,000-year, radiocarbon-dated record of Indian Summer Monsoon (ISM) variability in the Central Ganga Plain (CGP), offering a scientific baseline for future monsoon prediction and water-resource management.

Important CTC from this article for UPSC Why are Wetlands Important.Indian Summer Monsoon (ISM) and Palaeoclimate Reconstruction.What are Ox-Bow Lakes.AMS Radiocarbon dating