An appraisal of the sedimentation pattern and age profile of Perumal Lake, using radiometric analysis of 210Pb and 137Cs tracers

This present investigation delves into the intricate 210 Pb and 137 Cs radionuclides dating to govern the study of sedimentation rate, age modeling, and lifespan of the Perumal lake in the Cuddalore district, Tamil Nadu. In the study area, the 01 core sediment was excavated at the length of 51 cm, and concern for the 210 Pb and 137 Cs radionuclides dating using an Alpha spectrometer 7200-04 and a Gamma-ray spectrometer GC-3520 instruments. From the robust outcome, the bathymetry survey investigates the bottom topography, with a mean depth of 3.1 m and a maximum length of 11.54 km. Subsequently, the mean value of bulk density, porosity, and water content in the vertical profile of the sediment esteems as 1.52 g/cm 3 , 32.47 g/cm 3 , and 1.61%, and sediment textures unveils predominately consists of clay composition and attributes with higher content of 210 Pb radionuclide in the sediments to affirms the rate and accumulation of the sediments in the aquatic environment. From the Constant Rate Supply (CRS) method, the 210 Pb radionuclide activity shows the mean accumulation rate (kg/m 2 /year) and sedimentation rate (cm/year) indicates 0.57 ± 0.05 (kg/m 2 /year) and 0.84 ± 0.07 (cm/year) dated since 1944AD to 2023AD. The mean sedimentation rate of 137 Cs radionuclides activity for 1963AD and 1986AD implies 0.57 ± 0.04 (cm/year) and 0.43 ± 0.03 (cm/year). From the computation, the lifespan of the lake is 369.05 years and 543.86 years with respect to 210 Pb and 137 Cs activities, respectively. The sedimentation rate is crucial in diminishing the lake from the future accumulation of water and sediments in the aquatic environments.