Land use change can broadly be defined as the conversion of land from its natural state to an alternative state providing a function to humans.
As the human population has grown, increased demands on land have come from:
This has led to land being modified from its natural state to support these anthropogenic demands. Land use, land use change and forestry (LULUCF) has an impact on the local environment through altering vegetation, hydrology and soil conditions which, in certain cases, also contributes to climate change.
For example, direct releases of carbon stored in terrestrial stores (such as organic material) to the atmospheric stores (resulting in increased concentrations of greenhouse gases) results from agricultural activity (see below) and deforestation.
A combination of the global population growing to over 7.5bn people, and a significant increase in the average wealth of the population, has resulted in significant increases in demand for food and other natural resources (such as cotton). This, in turn, has led to increases in agricultural activity to provide for this demand. This increase in farming has contributed to climate change in a number of ways:
It is estimated that livestock are responsible for 18% of greenhouse gas emissions, which is greater than those from all means of transportation combined (see Link)
The removal of natural vegetation to make room for agriculture, urban areas or to extract the natural resources (such as wood for energy or furniture or plants that have medical properties) as part of such natural vegetation is a further component of land use change that has contributed to climate change. Vegetation and soils are key components of the terrestrial carbon store, and are responsible for the biological pump that extracts carbon from the atmospheric store and locks this carbon in the terrestrial store, through the natural process of photosynthesis (see link). The removal of this vegetation risks the release of this trapped carbon (in particular where the vegetation is burnt for energy or decomposes over time) back to the atmosphere, and removes the capacity of the land to absorb carbon from the atmosphere.
Reduction in the demand for wood and carbon intensitive meat and dairy products, or an alternative (low carbon) means of producing these products is required to reduce the impact of LULUCF. This requires technological advances and the wider adoption of agricultural best practices, changing behaviour to reduce the carbon intensity of an individual's diet and/or reducing population growth. This is explored more in this section
