Land Use Analysis

What is Land Use?

The first step in land use analysis is to map the land covers and land uses of a study area. There is an important distinction between land cover and land use.

Land cover is the physical cover of the land. For example, two common types of land cover are built and forest. Land cover can be observed and documented via remote sensing using sensors that are mounted on satellites, airplanes, or ground-based platforms. Cartographic methods are necessary to convert the information from the sensors into maps of land cover categories. Maps of land cover indicate what is on the landscape physically.

Land use is the purpose for which humans use the land. For example, common land uses are residential and recreational. Remote sensing techniques usually do not reveal land use because they give information about only the physical state of the land. A single land cover type may have many uses. For example, humans can use the forest land cover simultaneously for tourism, biodiversity conservation, and water quality protection. It is usually necessary to collect social data to determine land use, because land use is a social phenomenon.

Scientists are constantly developing more sophisticated methods to generate maps of land cover and to record the various land uses for each land cover. When maps of land use are available from more than one point in time, investigators usually want to characterize land use and land cover change. If the land uses are categories, then a transition matrix is commonly used to summarize the land transitions among the categories over time.

Why do Humans use the Land the Way they Do?

The second step in land use analysis is to understand why humans choose some land uses over other possible uses. The philosophical orientation of the investigator can influence the approach taken to attain this understanding. For example, an economist is likely to examine land prices and financial subsidies in an attempt to understand why developers prefer some locations over others for suburbanization. Sociologists may consider family dynamics and customs to understand how settlers decide to colonize a forest in a manner that maximizes land for future generations. Geologists might examine the soil fertility to explain the spatial distribution of farms. Regardless of the orientation of the investigator, analysts usually find it helpful to use both quantitative and qualitative techniques. Quantitative techniques include statistical methods to examine the association between the patterns in the land use maps and other variables such as prices, family structure, and soil fertility. Qualitative techniques include interviews with stakeholders and historical research concerning the policies that have guided land use decisions.

Land use analysis faces daunting methodological and conceptual challenges. Statistical analysis is complicated by the fact that the results can be sensitive to many characteristics of scale. These characteristics include the spatial, temporal, and categorical scales of the data in terms of both extent and resolution. Furthermore, the data are usually observational, that is, the data are not obtained from controlled experiments, and so large statistical associations do not necessarily guarantee cause-and-effect relationships. Qualitative analysis faces the same challenges. Some of these challenges derive from the fact that the land use system is a complex web of many interacting decision makers who are constantly responding to a variety of types of dynamic information. A major challenge for land use analysts is to be able to state clearly the evidence for a particular hypothesis for a particular domain at a particular scale and not get lost in the complexity. Some scientists use modeling to help gain an understanding of the land system. A land-change model is a computerized algorithm that shows the implications of the many assumptions that it synthesizes. It usually includes a calibration procedure during which it examines the past dynamics of the land use system. Then it can project future land uses based on either an extrapolation of past trends or alternative assumptions.

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