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On a worldwide scale, land use and land cover changes (LULCC) is a major driver of global change and biodiversity erosion. This study aims to monitor at the scale of Sri Lanka, LULCC and vegetation dynamics, to identify the main changes and their drivers. It places emphasis on multiscale geospatial monitoring with satellite data but also mobilises the interdisciplinary knowledge of a research programme. First, national scale data allows the identification of major changes with the MODIS NDVI dataset using Mann-Kendall tests and time profile analysis. A second local scale was mobilised with a systematic diachronic visual interpretation of high-resolution images on Google Earth. The third step, a macro-regional scale focus on the South and East coasts, used LANDSAT imagery (Stacked K-means) verified by field studies (botanical and vegetation analysis, and interviews). About 92.5% of the island of Sri Lanka is stable or presents no significant trends in the vegetation cover. 5% show a significant positive (greening) trend between 2000 and 2020 around the Puttalam lagoon, west of the Samanalawewa Reservoir, in the Udawalawe National Park, east and north of Ella, and the Nuwaragala Forest Reserve. Only about 2.5% (165,000 ha) of the Island shows a negative significant trend mainly in the periphery of Colombo and Trincomalee. The first driver is a set of national planning decisions in terms of infrastructure development (including urban growth, housing programmes and agricultural fields, and the management of protected areas). The second driver comes under rural dynamics with increasing tree density in rural landscapes over the Uva Province. Infrastructure development initiated by the state, creates both underlying conditions for other activities and negative impacts on coastal ecosystems, such as degradation of wetlands (including protected areas). [ABSTRACT FROM AUTHOR]

Remote sensing images of AD 1991-2011 and field observations help evaluate shoreline changes (erosion and accretion) in Puducherry and Tamil Nadu states of southeastern India. A minor harbor was constructed during AD 1986-1989 in the coast of Puducherry, and it initiated the gradual process of shoreline modification. In the subsequent years, beaches located toward the north of the harbor suffered erosion (−0.12-−4.19 m/year) and there was accretion (0.27-7.25 m/year) in the southern beaches. However, the man-made structures (seawall and groin) have reduced the shoreline changes after AD 2004. In the last two decades, the rate of erosion area-wise gradually decreased (0.24-0.013 km/year) and accretion remained constant (0.019 km/year). Our results suggest that accretion happened in the southern side of the breakwaters and erosion occurred in the northern part. Presence of groins structures in the region in the northern part has also provoked accretion in the south and erosion in the northern side close to the State of Tamil Nadu. [ABSTRACT FROM AUTHOR]

A violent outbreak of civil unrest (Jul 7–19, 2021) triggered immediately after the incarceration of the former South African president claimed 337 lives and brought disruptive damages to societal movements, environment, and COVID-19 containment measures. The present work aimed to analyze the hotspots of fire sites, its significances on societal activities, air quality and COVID-19 pandemic using ground based and geospatial data. The results revealed steady rise in air pollution levels all through the region due to increase in fire activities. Positive influence on the regional air quality was observed to be high than the limits set forth by WHO. The daily mean values of PM 2.5 (62.37–104.34 μg/m3) and PM 10 (108.86–156.78 μg/m3) presented potential short and long-term risks to public health. Similarly, COVID-19 cases also increased during the social unrest period even when the community mobility was less than the normal conditions. This type of cost benefit analysis proves to provide evidence of deteriorating air quality and aids to examine the adverse impacts on human health during the global pandemic. • Remote Sensing and GIS tools to evaluate environmental degradation due to civil unrest. • Evidences of decreased public mobility during the unrest period. • Increase in PM 2.5 and PM 10 particles during the unrest period due to arson. • Riot episodes eventually resulted in a surge of COVID-19 cases. [ABSTRACT FROM AUTHOR]