Desertification is a type of gradual land degradation of fertile land into arid desert due to a combination of natural processes and human activities. This spread of arid areas is caused by a variety of factors, such as overexploitation of soil as a result of human activity and the effects of climate change. Geographic areas most affected are located in Africa, Asia and parts of South America. Drylands occupy approximately 40–41% of Earth's land area and are home to more than 2 billion people. Effects of desertification include sand and dust storms, food insecurity, and poverty.
The geography of New Caledonia (Nouvelle-Calédonie), an overseas collectivity of France located in the subregion of Melanesia, makes the continental island group unique in the southwest Pacific. Among other things, the island chain has played a role in preserving unique biological lineages from the Mesozoic. It served as a waystation in the expansion of the predecessors of the Polynesians, the Lapita culture. Under the Free French it was a vital naval base for Allied Forces during the War in the Pacific.
Land degradation is a process in which the value of the biophysical environment also biochemical environment is affected by a combination of human-induced processes acting upon the land. It is viewed as any change or disturbance to the land perceived to be deleterious or undesirable. Natural hazards are excluded as a cause; however human activities can indirectly affect phenomena such as floods and bush fires.
The Sahel region of Africa has long experienced a series of historic droughts, dating back to at least the 17th century. The Sahel region is a climate zone sandwiched between the Sudanian Savanna to the south and the Sahara desert to the north, across West and Central Africa. While the frequency of drought in the region is thought to have increased from the end of the 19th century, three long droughts have had dramatic environmental and societal effects upon the Sahel nations. Famine followed severe droughts in the 1910s, the 1940s, and the 1960s, 1970s and 1980s, although a partial recovery occurred from 1975-80. The most recent drought occurred in 2012.
Regime shifts are large, abrupt, persistent changes in the structure and function of ecosystems, the climate, financial systems or other complex systems. A regime is a characteristic behaviour of a system which is maintained by mutually reinforced processes or feedbacks. Regimes are considered persistent relative to the time period over which the shift occurs. The change of regimes, or the shift, usually occurs when a smooth change in an internal process (feedback) or a single disturbance triggers a completely different system behavior. Although such non-linear changes have been widely studied in different disciplines ranging from atoms to climate dynamics, regime shifts have gained importance in ecology because they can substantially affect the flow of ecosystem services that societies rely upon, such as provision of food, clean water or climate regulation. Moreover, regime shift occurrence is expected to increase as human influence on the planet increases – the Anthropocene – including current trends on human induced climate change and biodiversity loss. When regime shifts are associated with a critical or bifurcation point, they may also be referred to as critical transitions.
The Great Green Wall or Great Green Wall of the Sahara and the Sahel is a project adopted by the African Union in 2007, initially conceived as a way to combat desertification in the Sahel region and hold back expansion of the Sahara desert, by planting a wall of trees stretching across the entire Sahel from Djibouti, Djibouti to Dakar, Senegal. The original dimensions of the "wall" were to be 15 km wide and 7,775 km long, but the program expanded to encompass nations in both northern and western Africa. The concept evolved into promoting water harvesting techniques, greenery protection and improving indigenous land use techniques, aimed at creating a mosaic of green and productive landscapes across North Africa. Later it adopted the view that desert boundaries change based on rainfall variations.
In hydrology, oasification is the antonym to desertification by soil erosion. This technique has limited application and is normally considered for much smaller areas than those threatened by desertification.
The Lancaster Environment Centre (LEC) in Lancaster, England, is an interdisciplinary centre for teaching, research and collaboration at Lancaster University, founded in 2007.
Billie Lee Turner II is an American geographer and human-environmental scientist, member of the National Academy of Sciences and other honorary institutions. Prominent among the third generation of the Berkeley School of Latin Americanist Geography and cultural ecological research, he has been a leader in bridging this work with the Chicago School of natural hazards and risk research. In August 2008, he took a position as the first Gilbert F. White Chair in Environment and Society at Arizona State University, where he is affiliated with the School of Geographical Sciences and Urban Planning and the School of Sustainability. In November 2015, he was named a Regent’s Professor, the highest faculty honor that can be bestowed by Arizona State University.
Mark A. Burgman is an Australian ecologist, Professor at the University of Hawaiʻi at Mānoa from 2024 and Emeritus Professor of Risk Analysis & Environmental Policy and former Director of the Centre for Environmental Policy at Imperial College London. He was Director of the Australian Centre of Excellence for Risk Analysis (ACERA), latterly CEBRA, and Adrienne Clarke Chair of Botany at the University of Melbourne until 2017. He co-led The SWARM Project at the University of Melbourne.
Ibi, Burkina Faso is a village in Rollo Department of Bam Province in northern Burkina Faso, West Africa. It has a population of 1374, mostly Mossi peoples. It is accessed by a track from Rollo and is very remote, even by the standards of northern Burkina Faso. There are no vehicles in the village other than mopeds, carts and bicycles and traditional agriculture is the main occupation.
Environmental anthropology is a sub-discipline of anthropology that examines the complex relationships between humans and the environments which they inhabit. This takes many shapes and forms, whether it be examining the hunting/gathering patterns of humans tens of thousands of years ago, archaeological investigations of early agriculturalists and their impact on deforestation or soil erosion, or how modern human societies are adapting to climate change and other anthropogenic environmental issues. This sub-field of anthropology developed in the 1960s from cultural ecology as anthropologists borrowed methods and terminology from growing developments in ecology and applied them to understand human cultures.
Nickel mining in New Caledonia is a major sector of the New Caledonian economy. The island contains about 7.1 million tonnes of nickel reserves, about 10% of the world's total. With an annual production of 200,000 tonnes in 2020, New Caledonia was the world's fourth largest producer after Indonesia (760,000), Philippines (320,000), and Russia (280,000), followed by Australia (170,000) and Canada (150,000).
Michael Mortimore was a British geographer and a prolific researcher of issues in the African drylands. He was an academic in Nigerian universities for over 25 years. He ran a British research consultancy, Drylands Research. He is best known for an anti-Malthusian account of population-environment relationships, More People, Less Erosion, and field-based studies of adaptation to drought.
The Journal of Political Ecology is an annual open access peer-reviewed academic journal covering political ecology. It was established in 1994 as one of the first open access journals in the social sciences, by James B. Greenberg and Thomas K. Park, to experiment with online formats and to showcase new work in the emerging field of political ecology. The current editors-in-chief are Simon Batterbury, Casey Walsh, Judith Krauss and Jens Friis Lund. There is an international editorial board.
Andrew Warren is a British physical geographer. He is Emeritus Professor of Geography at University College London, UK.
Ecofeminism is a branch of feminism and political ecology. Ecofeminist thinkers draw on the concept of gender to analyse the relationships between humans and the natural world. The term was coined by the French writer Françoise d'Eaubonne in her book Le Féminisme ou la Mort (1974). Ecofeminist theory asserts a feminist perspective of Green politics that calls for an egalitarian, collaborative society in which there is no one dominant group. Today, there are several branches of ecofeminism, with varying approaches and analyses, including liberal ecofeminism, spiritual/cultural ecofeminism, and social/socialist ecofeminism. Interpretations of ecofeminism and how it might be applied to social thought include ecofeminist art, social justice and political philosophy, religion, contemporary feminism, and poetry.
Caroline King-Okumu is an international development opportunities manager for the UK Centre for Ecology and Hydrology. She was formerly a senior researcher for the International Institute for Environment and Development (IIED). Her major areas of research are dryland ecosystems, economic and environmental assessment, and climate change. She is considered an international expert on land and water management, particularly drylands agriculture. King-Okumu is based in Kenya but is involved in research and projects throughout the world.
Jayne Belnap is an American soil ecologist. Her expertise lies in desert ecologies and grassland ecosystems.
Elisabeth Huber-Sannwald is an Austrian researcher specializing in ecosystem ecology. She is a Full Research Professor in Ecology and Global Environmental Change as well as the Department Head of Instituto Potosino de Investigación Científica y Tecnológica (IPICYT) in San Luis Potosí, Mexico.
