Colombia has approximately 379,954 hectares of mangrove forests distributed along the Pacific Ocean and the Caribbean Sea coasts. Such forests are experiencing the highest annual rate of loss recorded in South America and, in the last three decades, approximately 40,000 hectares have been greatly affected by natural and, especially, human impacts. This study determined, by the use of Landsat multispectral satellite images, the evolution of three mangrove forests located in the Colombian Caribbean Sea: Malloquín, Totumo, and La Virgen swamps. Mangrove forest at Mallorquín Swamp recorded a loss of 15 ha in the period of 1985–2018, associated with alterations in forest hydrology, illegal logging, urban growth, and coastal erosion. Totumo Swamp lost 301 ha in the period 1985–2018 associated with changes in hydrological conditions, illegal logging, and increased agricultural and livestock uses. La Virgen Swamp presented a loss of 31 ha in the period of 2013–2018 that was linked to the construction of a roadway, alterations of hydrological conditions, illegal logging, and soil urbanization, mainly for tourist purposes. Although Colombian legislation has made efforts to protect mangrove ecosystems, human activities are the main cause of mangrove degradation, and thus it is mandatory for the local population to understand the value of the ecosystem services provided by mangroves.

In the Antarctic Peninsula, most important activities are touristic visits, from the second half of the 20th Century, and scientific investigation linked to 75 research stations. Beach litter content/abundance was investigated at 17 beaches in Admiralty Bay (King George Island, Antarctica) and the type of plastic material was determined by Raman spectroscopy. An average value of 0.16 items m−1 was observed. Wood items consisted of processed wood fragments representing 47.27% of the total. Foam represented 21%, hard plastic pieces 9.68% (consisting of polyvinyl chloride or high density polyethylene), metal 3.37%, rubber fragments 2.81%, foamed plastic pieces 2.66% (composed by polystyrene), the rest of categories representing less than 2% of the total. Wood debris and metal are essentially remnant objects of ancient whaling activities and research expeditions, polyurethane and expanded polystyrene materials have different origins and hard plastic, rubber, paper/cardboard and paint fragments seem mostly linked to present research activities.

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The levels of four toxic heavy metals (Hg; Cr; Cd; Ni) present in 17 sediment samples of the Mallorquin lagoon -Barranquilla (N Colombia) were investigated in order to assessing the potential risks of accumulation. The sample preparation was performed by acid microwave digestion with "Multiwave" system, carried out using GFAAS. High contamination levels, especially for Hg, Cr and Cd, were detected in samples M4 (0

Beaches on the eastern margin of Tayrona National Natural Park experienced stability and even accretion over the last decade, in contrast to general erosion along the Colombian Caribbean coast. The objective of this study is to characterize shoreline change and analyze the factors contributing to the accretionary trend. Orthorectified satellite images, combined with topography from both drone images and RTK-DGPS measurements, were used to map successive shorelines from 2002-2008. Net shoreline movement and shoreline migration rates revealed these beaches had an accretionary trend, with the exception of Piscina Beach that eroded during the time period. The maintenance of natural inputs of sediment from local rivers, redistributed by littoral drift with sediment bypassing across the small headlands limiting the beaches, the resilience of the beaches to the impact of hurricanes and low human pressure allows for a positive sedimentary budget for the beaches. Piscinas Beach is the most cut off from fluvial sediment input, and despite it has a coral reef barrier, its dissipative profile indicate that it is the most exposed to wave impact.