Interactions amongst multiple causes
The main direct drivers of land degradation and associated biodiversity loss are expansion of crop and grazing lands into native vegetation (i.e., habitat loss via ecosystem transformation), unsustainable agricultural and forestry practices, climate change, and, in specific areas, urban expansion, infrastructure development and extractive industry. Rapid expansion and unsustainable management of croplands and grazing lands is the most extensive global direct driver of land degradation. Intensified land-management systems have greatly increased crop, livestock and wood fiber yields in many areas of the world, but, when inappropriately managed, can result in high levels of land degradation, including soil erosion, fertility loss, excessive ground and surface water extraction, salinization, and eutrophication of aquatic systems.
Land degradation is almost always the result of multiple interacting causes. Human activities that are the direct causes of land degradation are ultimately determined by multiple underlying causes, including economic, demographic, technological, institutional and cultural drivers. Extreme poverty, combined with resource scarcity and inequitable access to resources, can contribute to land degradation and unsustainable levels of natural resource use, but is rarely the major underlying cause of either. Single-factor explanations, such as extreme poverty, fail to address the multiplicity of underlying causes that typically lead to unsustainable land-use practices. In many impoverished rural areas, these underlying causes typically include disputes over land rights, poor access to markets and financial credit, insufficient investment in research and development, sector-focused development plans that pay no attention to other sectors, and weak governance institutions. Local land-use practices that degrade land have to be interpreted in the context of wider national policies and integration with regional and global markets.
Some major knowledge gaps related to causes/drivers of land degradation are
- The social and environmental consequences of interactions between climate change and land degradation drivers, including for efforts to avoid land degradation and restore degraded land
- Linkages between land degradation and restoration and distant social, economic and political processes
- Interactions among land degradation, poverty, climate change and the risk of conflict and of migration
John Parrotta