Sedimentation rates and sediment age of the high-altitude cold desert Ramsar Wetland, the Chandratal, inferred from radionuclide (210Pb and 137Cs) technique.

Abstract

In the current scenario, the pristine Himalayan Wetlands are under endangerment due to higher sedimentation rate, including siltation, reduction of ecological value, pollution, and significant anthropogenic encroachment along with advanced civilization. The more increased sedimentation reduces the depth and existing expansion of the Wetland. This study articulates the record of sedimentation in the Chandratal present in Western Himalaya, Himachal Pradesh, India, at the altitude of 4300m. The sedimentation rate of the Chandratal was calculated based on a 1-m core sample considering isotopes of 137Cs and 210Pb dating techniques. The present study based on the Constant Rate of Supply (CRS) model of 210Pb reveals that the Wetland experienced an average sedimentation rate of 1.75 ± 0.04cm/year during the last 63years observed from 1953 to 2016. The 137Cs peak method-based calculated sedimentation rate of the Chandratal is 1.6 ± 0.02cm/year representing the years for about 62years from 1954 to 2016. The Wetland's functional survival prevalence was estimated to be 420 and 459years based on 210Pb and 137Cs dating techniques, respectively. The study communicates that the magnified human interference in the catchment area of the Chandratal is accountable for the faster sedimentation in recent years.