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Environmental Impact of Gold Mining
Published in Mritunjoy Sengupta, Environmental Impacts of Mining, 2021
Small-scale mining in Ghana poses serious environmental impact on the surrounding communities. Virgin forest and fertile farmlands located in the middle belt of the country, which includes a part of the Brong Ashante region, western region, and some parts of the eastern regions are disappearing as gold mining has become the dominant activity in these areas. The majority of the challenges posed by small-scale mining in Ghana are experienced in environmental degradation and destruction and its effect on several ecological systems. Land degradation, mercury pollution, and pollution of water bodies are some of the major challenges posed by small-scale surface gold mining. Small-scale surface mining is one of the greatest agents of land degradation, destroying about 13% of the total forested land that surface mining has destroyed in Ghana. A study revealed that surface mining resulted in about 58% deforestation and a substantial 45% loss of farmland within the western region of Ghana. In some places, riverbanks are mined to a depth of 35 m expanding to about 60 m wide. Land degradation results in a threat to biodiversity conservation, with devastating effects on soil ecosystem leading to increase in soil temperature, loss and depletion of soil nutrients, changes in topography, erosion, destruction of its unique habitats and fauna, and making land less productive. The majority of the mining concessions are found in forests, agricultural lands, and human settlements resulting in competition for land and depriving farmers access to farming land.
Drought Management for Landscape and Rural Security
Published in Saeid Eslamian, Faezeh Eslamian, Handbook of Drought and Water Scarcity, 2017
Sandra Reinstädtler, Shafi Noor Islam, Saeid Eslamian
Landscapes and rural areas are becoming highly disturbed while being threatened in the context of land degradation by intensified land use, reduced groundwater accessibility, reduced precipitation to under 250–80 or even 0 mm/year, as well as water scarcity and aridity in general, resulting in the desertification of dry lands in the long run. But it has to be emphasized that drought is not to be equated with aridity or desertification: aridity is a dominant feature of dry regions, which refers to the permanent condition of low average precipitation or the destruction of available water. For precising the difference between drought, land degradation, or desertification, the terms next to the already described one of “drought” should be clear: “land degradation” in general describes surface decomposition in productive dry lands. Degradation of land resources is one step before desertification. It may lead to desertification of an area, which in its place was not compulsorily an arid region earlier. Desertification is a form of land degradation in arid, semiarid, and dry wet–dry areas, which results from different factors including climatic changes and human activities [89]. In 1949 the term “desertification” was used for the first time in west Africa by the French forester Aubréville [89], whereas in 1972 the term was adopted by the United Nations Conference on the Human Environment (later UNEP) and in 1977 the first world map of desertification was drawn up in Nairobi. In this process, up to 1977, desertification was realized for the first time as being a continuing worldwide process.
Land Degradation Assessment and Monitoring of Drylands
Published in Prasad S. Thenkabail, Remote Sensing Handbook, 2015
Marion Stellmes, Ruth Sonnenschein, Achim Röder, Thomas Udelhoven, Stefan Sommer, Joachim Hill
A nowadays widely accepted definition of land degradation and desertification is provided by the UNCCD. According to the UNCCD (1994), land degradation is defined as “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”. Desertification is defined as “land degradation in arid, semiarid and dry sub-humid areas, resulting from various factors, including climatic variations and human activities”.
Assessment of the effects of land use/cover changes on soil loss and sediment export in the Tul Watershed, Northwest Ethiopia using the RUSLE and InVEST models
Published in International Journal of River Basin Management, 2023
At the worldwide level, land degradation is a severe challenge to the productive capacity of land and water resources (Nachtergaele et al., 2013). Although the majority of the rural poor in the region rely largely on land resources, Sub-Saharan Africa has seen severe land degradation as a result of land use/cover changes (Nkonya et al., 2016). Losses of soil, water, vegetation cover, biodiversity, as well as nutrient depletion, are all signs of land degradation. The most important indication of land degradation is soil degradation. Soil erosion by water and nutrient depletion are the most important indicators of soil degradation (Ewunetu et al., 2021). Due to LULC dynamics, bare land growth, soil erosion, and sediment yield are all serious issues of soil degradation in Ethiopia (Borrelli et al., 2013).
Heavy Metal Phytoremediation by Bioenergy Plants and Associated Tolerance Mechanisms
Published in Soil and Sediment Contamination: An International Journal, 2021
Land degradation is a general term used for denoting a wide variety of land conditions, such as desertification, salinization, heavy metal contamination, erosion, or encroachment of invasive species (Gibbs and Salmon 2015). This condition can reduce the productivity of the land and can make it unfit for agriculture (Noojipady, Prince, and Rishmawi 2015). The land degradation is increasing and extending to several parts of the world including cultivated areas (20%), broadleaved forests (24%), needle-leaved forests (19%) and rangelands (20–25%) (Bai et al. 2008). In European economic area and the West Balkans, approximately 3 million sites are potentially polluted due to industrial activities such as mining and smelting; domestic and municipal wastes; fertilizers and chemicals used in agriculture; petroleum-derived products; and fumes generated by transportation (Food and Agricultural organization of United States (FAO) 2018).
Monitoring interannual dynamics of desertification in Minqin County, China, using dense Landsat time series
Published in International Journal of Digital Earth, 2020
Xiaolin Zhu, Kwok Huen Leung, Wing Sze Li, Lek Kin Cheung
Desertification indicates land degradation and conversion to drylands (Zucca et al. 2011). Currently, deserts occupy approximately 40% of the global land area, and desertification affects more than 1 billion people around the world (Tang et al. 2016). China is one of the countries facing serious desertification. By 2014, desertified lands consist of 2.61 million km2, accounting for 27.2% of the total land of China (Feng, Jia, and Li 2016), and 99.6% of these deserts are located in north and northwest China (Zhou et al. 2015). Northwest China has most of the deserts of China and is the origin of sandstorms in China (Wang et al. 2004). Northwest China still faces the threat of desertification. Over 90% of the grassland in the region has suffered different degrees of land degradation (Zhou et al. 2015).