Land use and reclamation

Land use and reclamation affect and are affected by climate change in complex ways. The creation of new land from sea- or riverbeds or the restoration of an area to its previous natural state has the potential to shape the complex interaction between land cover and the atmosphere, an interaction that affects climate change as much as do GHG emissions.

Background

The different types of land surface differently affect the interaction between the Earth and the atmosphere. Land cover and land-use patterns are affected by the distribution and density of human population, by its activities, and by natural causes. Land-use changes in urban and peri-urban areas, including land reclamation, often drive environmental change, reducing or increasing greenhouse gas (GHG) emissions. In turn, land use and land cover are affected by climate change through erosion, desertification, drought, heavy precipitation, ocean warming, sea-level rise, salinization, heat waves, increases in wind intensity, decline of glaciers and snow cover, and drying of wetlands, among other processes.

The role of land-use change in overall climate change is not well understood. However, if most of the observed increase in temperatures in recent decades can be attributed to GHG emissions, then urban and industrial land uses can be seen as coresponsible for global warming.

Land Creation, Land Rehabilitation, and Soil Remediation

Land reclamation as a vehicle of land-use change can be one of two different processes. One consists in the creation of new land where there was once water, either in the sea or in a riverbed. Many cities on all continents have used this process to create new residential or business areas, harbors, airports, and other infrastructure. also includes the construction of artificial islands for tourism-related activities or the creation or restoration of beaches in areas affected by beach erosion. Another form of land reclamation is the draining of seasonally submerged lands to convert them to agricultural uses and, in some places, also to control the agent of malaria.

The other form of land reclamation, also called land rehabilitation, consists in restoring an area after it has suffered physical degradation. Such degradation may be natural (for example, erosion) or (for example, pollution, soil contamination, or mining operations). Land can be rehabilitated to allow a new use, such as housing or commercial development, or it may be restored to its natural state in the interests of conservation. In the latter case, knowledge of the land’s original soil, flora, and fauna characteristics will facilitate their restoration. Soil remediation, a soft form of land rehabilitation, is the removal of industrial contaminants in soil and water to reduce the risks for human health and for the ecosystem.

Land-Use and Climate Change

GHG emissions and other anthropogenic and natural factors have the capacity to affect climate change. Urban and peri-urban areas have probably the greatest influence on climate change, being responsible for most GHG emissions. This influence is expected to increase, according to United Nations projections of urban population growth and urban sprawl. Outside urban areas, changes in land cover—including deforestation, reforestation, agriculture, and irrigation—affect temperatures, precipitation, and atmospheric circulation. Replacing a with agricultural lands reduces evaporation and consequently raises temperatures, while irrigation increases evaporation and, eventually, precipitation. Similar changes can be associated with of snow areas, with planting trees as carbon sinks, and with the creation of new areas for growing crops for fuel.

A changing climate can in turn affect land cover and land use. Climate change affects land cover by creating new risks associated with temperature rise, flooding of low areas, dike collapses, sea-level rise, storms and other natural disasters, erosion of coastal areas, salinization, droughts, the quantity and quality of groundwater resources, water scarcity, air quality, land subsidence, and deterioration of soils. These events can lead to habitat destruction, invasion by alien species, ecosystem fragmentation, and species loss, with profound and irreversible impacts on biodiversity. Climate change also directly affects many other economic and social activities that in turn affect land-use patterns. In some parts of the world, for example in small island states, the forecasted climate change and sea-level rise will make land one of the rarest and most vulnerable resources. In this context, cities will probably be the land-use type most affected by climate change, especially cities located on low coastal zones.

Land-Use Planning in Adaptation and Mitigation Strategies

The interaction between climate changes and land-use calls for innovative adaptation and mitigation measures. Land-use planning can have an important role in climate change adaptation strategies at the local level, and can contribute to wider mitigation strategies as well. These measures include, for example, the coordination of public and private stakeholders involved in land-use and land reclamation processes, tax benefits, innovative financing mechanisms, and other incentives for the use of renewable energy.

Building codes can also be changed to incorporate norms for GHG emissions in public buildings, green roofs, within household dwellings, and energy to prevent the production of carbon dioxide. Land-use planning strategies, including land zoning, must discourage automobile use, provide adequate incentives for mass transit, promote mixed land use and infill development in sites previously used by other urban functions (including land rehabilitated or areas subjected to soil remediation), and promote higher densities and compact urban layouts, stimulating walkability.

Context

The interaction between landuse and land reclamation, on one side, and climate change, on the other, is exceptionally complex and is still insufficiently understood. However, the evidence available suggests that changes on each side of this relation affect the other, and, consequently, failure to consider these interactions and to act accordingly may have long-lasting negative consequences for the environment and for the economy and society. For that reason, measurable, verifiable, and reportable actions on adaptation and mitigation, in the field of land-use planning, must be taken sooner rather than later, in all countries, to reduce the environmental, economic, and social effects that would otherwise result from inaction. Special support for adaptation measures, including technology transfer and innovative finance, should be provided by the international community to the poorer and more vulnerable countries.

Key Concepts

• anthropogenic: due to human sources or activities
• greenhouse gases (GHGs): trace atmospheric gases that trap heat, preventing it from escaping into space
• land reclamation: modification of unsuitable land to allow for some form of human use or for a return to its original natural state
• land rehabilitation: restoration of land that has suffered environmental degradation

Bibliography

"The Climate Benefits of Degraded Lands Reclamation and Restoration." National Wildlife Federation, 8 Sept. 2022, www.nwf.org/Educational-Resources/Reports/2022/The-Climate-Benefits-of-Degraded-Lands-Reclamation-and-Restoration. Accessed 21 Dec. 2024.

Intergovernmental Panel on Climate Change. Climate Change, 2007—Synthesis Report: Contribution of Working Groups I, II, and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Edited by the Core Writing Team, Rajendra K. Pachauri, and Andy Reisinger. Geneva, Switzerland: Author, 2008.

‗‗‗‗‗‗‗. Emissions Scenarios. Geneva, Switzerland: Author, 2000.

‗‗‗‗‗‗‗. Land Use, Land-Use Change, and Forestry: A Special Report of the IPCC. Edited by Robert T. Watson et al. New York: Cambridge University Press, 2000.

Organization for Economic Cooperation and Development. Literature Review on Climate Change Impacts on Urban City Centres: Initial Findings. Paris: Author, 2007.

‗‗‗‗‗‗‗. OECD Environmental Outlook to 2030. Paris: Author, 2008. es.