Deforestation and desertification

The Great Green Wall or Great Green Wall for the Sahara and the Sahel (French: Grande Muraille Verte pour le Sahara et le Sahel; Arabic: السور الأخضر العظيم, as-Sūr al-ʾAkhḍar al-ʿAẓīm) 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 City, Djibouti to Dakar, Senegal. The original dimensions of the "wall" were to be 15 km (9 mi) wide and 7,775 km (4,831 mi) 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.

Environmental philosophy is the branch of philosophy that is concerned with the natural environment and humans' place within it. It asks crucial questions about human environmental relations such as "What do we mean when we talk about nature?" "What is the value of the natural, that is non-human environment to us, or in itself?" "How should we respond to environmental challenges such as environmental degradation, pollution and climate change?" "How can we best understand the relationship between the natural world and human technology and development?" and "What is our place in the natural world?" Environmental philosophy includes environmental ethics, environmental aesthetics, ecofeminism, environmental hermeneutics, and environmental theology. Some of the main areas of interest for environmental philosophers are:

Mountaintop removal mining (MTR), also known as mountaintop mining (MTM), is a form of surface mining at the summit or summit ridge of a mountain. Coal seams are extracted from a mountain by removing the land, or overburden, above the seams. This process is considered to be safer compared to underground mining because the coal seams are accessed from above instead of underground. In the United States, this method of coal mining is conducted in the Appalachian Mountains in the eastern United States. Explosives are used to remove up to 400 vertical feet (120 m) of mountain to expose underlying coal seams. Excess rock and soil is dumped into nearby valleys, in what are called "holler fills" ("hollow fills") or "valley fills".

Agroforestry (also known as agro-sylviculture or forest farming) is a land use management system that integrates trees with crops or pasture. It combines agricultural and forestry technologies. As a polyculture system, an agroforestry system can produce timber and wood products, fruits, nuts, other edible plant products, edible mushrooms, medicinal plants, ornamental plants, animals and animal products, and other products from both domesticated and wild species.

Afforestation is the establishment of a forest or stand of trees in an area where there was no recent tree cover. There are three types of afforestation: natural regeneration, agroforestry and tree plantations. Afforestation has many benefits. In the context of climate change, afforestation can be helpful for climate change mitigation through the route of carbon sequestration. Afforestation can also improve the local climate through increased rainfall and by being a barrier against high winds. The additional trees can also prevent or reduce topsoil erosion (from water and wind), floods and landslides. Finally, additional trees can be a habitat for wildlife, and provide employment and wood products.

Water scarcity (closely related to water stress or water crisis) is the lack of fresh water resources to meet the standard water demand. There are two types of water scarcity. One is physical. The other is economic water scarcity. Physical water scarcity is where there is not enough water to meet all demands. This includes water needed for ecosystems to function. Regions with a desert climate often face physical water scarcity. Central Asia, West Asia, and North Africa are examples of arid areas. Economic water scarcity results from a lack of investment in infrastructure or technology to draw water from rivers, aquifers, or other water sources. It also results from weak human capacity to meet water demand. Many people in Sub-Saharan Africa are living with economic water scarcity.

Reforestation is the practice of restoring previously existing forests and woodlands that have been destroyed or damaged. The prior forest destruction might have happened through deforestation, clearcutting or wildfires. Three important purposes of reforestation programs are for harvesting of wood, for climate change mitigation, and for ecosystem and habitat restoration purposes. One method of reforestation is to establish tree plantations, also called plantation forests. They cover about 131 million ha worldwide, which is 3% of the global forest area and 45% of the total area of planted forests.

Desertification is a type of gradual land degradation of fertile land into arid desert due to a combination of natural processes and human activities.

Slash-and-burn agriculture is a farming method that involves the cutting and burning of plants in a forest or woodland to create a field called a swidden. The method begins by cutting down the trees and woody plants in an area. The downed vegetation, or "slash", is then left to dry, usually right before the rainiest part of the year. Then, the biomass is burned, resulting in a nutrient-rich layer of ash which makes the soil fertile, as well as temporarily eliminating weed and pest species. After about three to five years, the plot's productivity decreases due to depletion of nutrients along with weed and pest invasion, causing the farmers to abandon the field and move to a new area. The time it takes for a swidden to recover depends on the location and can be as little as five years to more than twenty years, after which the plot can be slashed and burned again, repeating the cycle. In Bangladesh and India, the practice is known as jhum or jhoom.

Illegal logging is the harvest, transportation, purchase, or sale of timber in violation of laws. The harvesting procedure itself may be illegal, including using corrupt means to gain access to forests; extraction without permission, or from a protected area; the cutting down of protected species; or the extraction of timber in excess of agreed limits. Illegal logging is a driving force for a number of environmental issues such as deforestation, soil erosion and biodiversity loss which can drive larger-scale environmental crises such as climate change and other forms of environmental degradation.