Monitoring of wetland turbidity using multi-temporal Landsat-8 and Landsat-9 satellite imagery in the Bisalpur wetland, Rajasthan, India

Raj Singh; Vara Saritha; Chaitanya B Pande

doi:10.1016/j.envres.2023.117638

Monitoring of wetland turbidity using multi-temporal Landsat-8 and Landsat-9 satellite imagery in the Bisalpur wetland, Rajasthan, India

Environ Res. 2024 Jan 15:241:117638. doi: 10.1016/j.envres.2023.117638. Epub 2023 Nov 14.

Authors

Raj Singh¹, Vara Saritha², Chaitanya B Pande³

Affiliations

¹ Department of Environmental Science, GITAM Deemed to be University, Visakhapatnam, 530045, India.
² Department of Environmental Science, GITAM Deemed to be University, Visakhapatnam, 530045, India. Electronic address: svara@gitam.edu.
³ Indian Institute of Tropical Meteorology, Pune, 411008, India; New Era and Development in Civil Engineering Research Group, Scientific Research Center, Al-Ayen University, Thi-Qar, Nasiriyah, 64001, Iraq.

PMID: 37972812
DOI: 10.1016/j.envres.2023.117638

Abstract

Satellite imagery has emerged as the predominant method for performing spatial and temporal water quality analyses on a global scale. This study employs remote sensing techniques to monitor the water quality of the Bisalpur wetland during both the pre and post-monsoon seasons in 2013 and 2022. The study aims to investigate the prospective use of Landsat-8 (L8) and Landsat-9 (L9) data acquired from the Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS) for the temporal monitoring of turbidity. Concurrently, the study examines the relationship of turbidity with water surface temperature (WST) and chlorophyll-a (Chl-a) concentrations. We utilized visible and near-infrared (NIR) bands to conduct a single-band spectral response analysis of wetland turbidity. The results reveal a notable increase in turbidity concentration in May 2022, as this timeframe recorded the highest reflectance (0.28) in the NIR band. Additionally, the normalized difference turbidity index (NDTI) formula was used to assess the overall turbidity levels in the wetland. The results indicated that the highest concentration was observed in May 2013, with a value of 0.37, while the second-highest concentration was recorded in May 2022, with a value of 0.25. The WST was calculated using thermal band-10 in conjunction with Chlorophyll-a, utilizing the normalized difference chlorophyll index (NDCI). The regression analysis shows a positive correlation between turbidity and WST, as indicated by R2 values of 0.41 in May 2013 and 0.40 in May 2022. Furthermore, a robust positive relationship exists between turbidity and Chl-a, with a high R2 value of 0.71 in May 2022. These findings emphasize the efficacy of the L8 and L9 datasets for conducting temporal analyses of wetland turbidity, WST, and Chl-a. Additionally, this research underscores the critical role of satellite imagery in assessing and managing water quality, particularly in situations where in-situ data is lacking.

Keywords: Chlorophyll-a; Normalized difference turbidity index; Remote sensing; Water quality; Water surface temperature.

MeSH terms

Chlorophyll / analysis
Chlorophyll A / analysis
Environmental Monitoring / methods
India
Satellite Imagery*
Wetlands*

Substances

Chlorophyll A
Chlorophyll