Coral Bleaching

Coral Bleaching

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).

Land Degradation

Land Degradation

Land degradation means reduction or loss, in arid, semi-arid and dry subhumid 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).

Compressive Soils

Compressive Soils

Compressible soils include both compressive and collapsible soils. Compressive soils are soils that are prone to volumetric change when subject to mechanical loading (USDA, 1990:30). Collapsible soils are metastable in that they are prone to volumetric change (collapse) on wetting and loading (Rogers, 1995).

Runoff / Nonpoint Source Pollution

Runoff / Nonpoint Source Pollution

Nonpoint sources of pollution refer to pollution sources that are diffused and without a single point of origin or not introduced into a receiving freshwater or maritime environment from a specific outlet. The pollutants are generally carried off the land by storm-water run-off. The commonly used categories for nonpoint sources are agriculture, forestry, urban areas, mining, construction, dams and channels, land disposal and saltwater intrusion (UN data, no date).

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