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No Turning Back after Desertification: The Future of Southern California
Desertification is defined as the dilapidation of biological productivity, which ultimately leads to desert-like conditions. The deterioration of land due to desertification is closely linked to climate change and other anthropogenic activities. Although the relationship between climate change and desertification is not fully understood, studies conducted by the United Nations Convention to Combat Desertification Secretariat (UNCCD) and the Millennium Ecosystem Assessment suggest that unsustainable agricultural practices paired with increased greenhouse gas emissions and a reduced carbon sink could lead to prolonged periods of extreme drought. Such events can have a dramatic impact on soil already depleted of nutrients, and freshwater availability.
Unsustainable agricultural practices that contribute to desertification include over-cultivation, overgrazing and poor irrigation practices. Deforestation also plays a role, as a decrease in vegetation results in a loss of topsoil. All of these activities are the result of the increasing imbalance between an expanding human population and an environment ill equipped to sustain it. The growing population is not the direct cause of desertification but it has led to the misuse of the land on a massive scale. Our rapidly increasing population has changed the former balance upon which the survival of agriculture depends, such as long uncultivated periods to allow the land to regain its fertility.