Ministry of Science & Technology

Reduced anthropogenic activities during COVID-19 imposed lockdown period indicated by decreased Colored Dissolved Organic Matter (CDOM) build-up and nutrients in the Mandovi Estuary

Posted On: 22 MAY 2021 5:26PM by PIB Mumbai

Goa: May 22, 2021


Monitoring the water quality is of utmost necessary for managing the health of the water body. Water quality can be assessed by its physical, chemical, biological, and microbiological characteristics of water. One of the chemical parameters of importance is the dissolved organic matter in the water (DOM), which is the largest reservoir of organic carbon in the aquatic environment. A fraction of this organic carbon absorbs light and imparts color to the water and hence known as colored dissolved organic matter (CDOM). The origin of CDOM can be either natural or from anthropogenic sources. CDOM absorbs light highly in the UV and blue regions of the solar spectrum and hence can have a positive or negative impact on the ecosystem. If a high amount of CDOM is present in the water it will not allow light to penetrate the water column and hence primary production will be hampered. While low levels of CDOM allow penetration of UV light to greater depths affecting the marine biota. The Mandovi and Zuari are the two main estuaries of Goa and have been exploited in recent years for various anthropogenic activities. The CDOM in the Mandovi Estuary was monitored since 2014, wherein high CDOM absorption was observed in the summer (especially in the midstream region) due to anthropogenic activities. In 2020 following the Government of India imposed COVID-19 lockdown (24th March- 8th June), a significant decrease of CDOM by almost 2 folds was observed in the midstream region. The Sentinel-2 satellite data also showed similar variations of CDOM absorption with low values during 2020. Apart from this, the concentration of dissolved nutrients in 2020 was also low compared to the previous reports. There was a complete standstill of anthropogenic activities such as operating pleasure cruises, water transport systems like barges, shipbuilding activities, and commercial establishments following the government-imposed lockdown, which might have reduced the CDOM and nutrients in the estuary.

Publication: Dias, A., Kurian, S., Thayapurath, S., and Pratihary, A.K. (2021). Variations of Colored Dissolved Organic Matter in the Mandovi Estuary, Goa, During Spring Inter-Monsoon: A Comparison With COVID-19 Outbreak Imposed Lockdown Period. Front. Mar. Sci. 8:638583. doi: 10.3389/fmars.2021.638583.





Follow us on social media: @PIBMumbai   Image result for facebook icon /PIBMumbai    /pibmumbai

(Release ID: 1720901) Visitor Counter : 82

Read this release in: Marathi