ABSTRACT
Land-use and land-cover change (LULCC), or more succinctly land change, is an integral component of global environmental change.[1] Land cover refers to the physical characteristics of Earth’s surface such as water, grass, trees, or concrete. Land use, on the other hand, refers to how the land is utilized by humans for various social and economic purposes. The same land cover may be used for different purposes. For example, a forest may be used for timber extraction or set aside as a protected area for conservation of wildlife. Land-use change refers to a change in the management of land by humans, which may or may not lead to land cover-change. LULCC is important for biogeochemical cycles such as nutrient cycling,[2,3] for biodiversity through its impacts on habitats,[4,5] and for climate by changing sources and sinks of greenhouse gases and land-surface properties.[6,7] LULCC also has important implications for the provision of ecosystem services on which both rural and urban societies depend.[8]
There is a large body of both theoretically and empirically grounded work on LULCC. These studies fall under the umbrella of the relatively new but growing discipline of land-change science. Several international science efforts such as the Global Land Project,[9] a joint research project of the International Geosphere-Biosphere Programme (https:// www.igbp.net) and the International Human Dimensions Programme (https://www.ihdp.org), are devoted to issues revolving around LULCC in recognition of the pivotal role it plays in the functioning of the Earth system. These issues
are treated at length in the many books and reports published specifi cally on the subject of LULCC.[10-20]
CAUSES AND CONSEQUENCES
The processes that lead to land change are numerous. These processes in many cases interact and collectively lead to larger impacts on the land cover than they would individually.[21,22] Although biophysical processes and predominant climatic conditions broadly determine the land cover in a particular location, human activities play a key role in creating the observed land-use and landcover patterns (Fig. 1) and may even create land uses that could not be supported by the climatic conditions at that locale (e.g., irrigated agriculture in extremely arid environments).
