{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T14:56:15Z","timestamp":1784300175914,"version":"3.55.0"},"reference-count":14,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2020,8,11]],"date-time":"2020-08-11T00:00:00Z","timestamp":1597104000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The SARS-CoV-2 (or COVID-19) lockdown in India, which started at an early stage of its infection curve, has been one of the strictest in the world. Air quality has improved in all urban centers in India, a major emitter of greenhouse gases (GHG). This study is based on the hypothesis that an abrupt halt in all urban activities resulted in a massive decline in NO2 emissions and has also altered coastal nitrogen (N) inputs; in-turn, this affected the trophic status of coastal waters across the country. We present the first evidence of an overall decline in pre-monsoon chlorophyll-a, a proxy for phytoplankton biomass, in coastal waters off urban centers during the peak of the lockdown in April. The preliminary field data and indirect evidence suggests the reduction in coastal chlorophyll-a could be linked to a net decline in nutrient loading, particularly of bioavailable N through watershed fluxes and atmospheric deposition. The preliminary results stress the importance of a further understanding of the relationship between fluctuations in anthropogenic N, due to lockdown measures and coastal ecosystem responses, as countries open-up to a business-as-usual scenario.<\/jats:p>","DOI":"10.3390\/rs12162584","type":"journal-article","created":{"date-parts":[[2020,8,11]],"date-time":"2020-08-11T09:28:57Z","timestamp":1597138137000},"page":"2584","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":49,"title":["Decline in Phytoplankton Biomass along Indian Coastal Waters due to COVID-19 Lockdown"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8192-7681","authenticated-orcid":false,"given":"Deepak R.","family":"Mishra","sequence":"first","affiliation":[{"name":"Department of Geography, University of Georgia, Athens, GA 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0956-1766","authenticated-orcid":false,"given":"Abhishek","family":"Kumar","sequence":"additional","affiliation":[{"name":"Department of Geography, University of Georgia, Athens, GA 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3213-7434","authenticated-orcid":false,"given":"Pradipta R.","family":"Muduli","sequence":"additional","affiliation":[{"name":"Wetland Research and Training Centre, Chilika Development Authority, Balugaon 752030, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sk. Md.","family":"Equeenuddin","sequence":"additional","affiliation":[{"name":"Department of Earth and Atmospheric Sciences, National Institute of Technology, Rourkela 769008, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gurdeep","family":"Rastogi","sequence":"additional","affiliation":[{"name":"Wetland Research and Training Centre, Chilika Development Authority, Balugaon 752030, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tamoghna","family":"Acharyya","sequence":"additional","affiliation":[{"name":"School of Sustainability, Xavier University, Puri 752050, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6324-4107","authenticated-orcid":false,"given":"Debadatta","family":"Swain","sequence":"additional","affiliation":[{"name":"School of Earth, Ocean and Climate Sciences, Indian Institute of Technology, Bhubaneswar 752050, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,8,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ramesh, R., Selvam, A.P., Robin, R., Ganguly, D., Singh, G., and Purvaja, R. (2017). Nitrogen Assessment in Indian Coastal Systems. The Indian Nitrogen Assessment, Elsevier BV.","DOI":"10.1016\/B978-0-12-811836-8.00023-9"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"20130121","DOI":"10.1098\/rstb.2013.0121","article-title":"The marine nitrogen cycle: Recent discoveries, uncertainties and the potential relevance of climate change","volume":"368","author":"Voss","year":"2013","journal-title":"Philos. Trans. R. Soc. B Biol. Sci."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"237","DOI":"10.1080\/00785236.1995.10422046","article-title":"Coastal eutrophication in relation to atmospheric nitrogen deposition: Current perspectives","volume":"41","author":"Paerl","year":"1995","journal-title":"Ophelia"},{"key":"ref_4","unstructured":"U.S. Environmental Protection Agency (USEPA) (1999). Deposition of Air Pollutants to the Great Waters. 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Nutrient load in the River Ganges during the COVID-19 lockdown phase: A ground zero observation. J. Regul. Stud., 79\u201391."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/12\/16\/2584\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T09:59:18Z","timestamp":1760176758000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/12\/16\/2584"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,8,11]]},"references-count":14,"journal-issue":{"issue":"16","published-online":{"date-parts":[[2020,8]]}},"alternative-id":["rs12162584"],"URL":"https:\/\/doi.org\/10.3390\/rs12162584","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,8,11]]}}}