Environmental Degradation

Wetland loss/degradation is a negative trend in wetland condition, caused by physical or direct/indirect human-induced processes, expressed as a long-term reduction or loss of at least one of the following: biological productivity, ecological role or value to humans (Olsson et al., 2019).

Seawater intrusion is the process by which saltwater infiltrates a coastal aquifer, leading to contamination of fresh groundwater (Prince Edward Island Department of Environment, Labour and Justice, 2011). 

A point source of air pollution is an identifiable stationary location or fixed facility from which air pollutants are released, which may be human-made or natural in origin (adapted from Kibble and Harrison, 2005; Dunne et al., 2014). 

Corals are subject to ‘bleaching’ when the seawater temperature is too high: they lose the symbiotic algae that give coral its colour and part of its nutrients. Severe, prolonged or repeated bleaching can lead to the death of coral colonies (United Nations, 2017).

Acid rain is rain that, in the course of its history, has combined with chemical elements or pollutants in the atmosphere and reaches the Earth’s surface as a weak acid solution (WMO/UNESCO, 2012).

Ambient (outdoor) air pollution is pollution that is present at concentrations that affect human health, ecosystems and agriculture. It is primarily measured through the presence of particulate matter (PM10 and PM2.5), ozone, nitrogen dioxide, sulphur dioxide and carbon monoxide in the air. Ambient air pollution is one of the leading environmental risk factors affecting urban and rural populations around the world, resulting in an estimated 4.2 million premature deaths in 2019 (WHO, 2024).

Permafrost is defined as ground that remains frozen at or below 0°C for a minimum of two consecutive years. Permafrost loss, also known as permafrost thaw, is the progressive loss of ground ice in permafrost, usually due to input of heat. Thaw can occur over decades to centuries over the entire depth of permafrost ground, with impacts occurring while thaw progresses. During thaw, temperature fluctuations are subdued because energy is transferred by phase change between ice and water.

Land degradation is the reduction or loss, in arid, semi-arid and dry sub-humid areas, of the biological or economic productivity and complexity of rainfed cropland, irrigated cropland or range, pasture, forest and woodlands resulting from land uses or from a process or combination of processes, including processes arising from human activities and habitation patterns such as soil erosion caused by wind and/or water; deterioration of the physical, chemical and biological or economic properties of soil; and long-term loss of natural vegetation (UNCCD, 1993). 

Sand mining (extraction) is defined as the removal of primary (virgin) natural sand and sand resources (mineral sands and aggregates) from the natural environment (terrestrial, riverine, coastal, or marine) for extracting valuable minerals, metals, crushed stone, sand and gravel for subsequent processing (UNEP, 2019).

Nonpoint sources of pollution refer to pollution that does not have a single point of origin or has not been introduced into a receiving freshwater or maritime environment from a specific outlet. The pollutants are generally carried off from the land by agricultural runoff, urban stormwater, atmospheric deposition or subaqueous groundwater discharges. The most common categories of nonpoint pollution are agriculture, forestry, urban areas, mining, construction, dams and channels, land disposal and saltwater intrusion.