Zoning, Landscape zoning or landscape functional zoning is a method, main working mode of spatial planers precisely landscape planners. In short it is a method of theoretically segmenting the land due to it's best using purposes, in other words ascribing the functions to the land like: agricultural land, recreation land, protected land, urbanized land and so on. And it is generally made on national scale by government. But more precisely, many land usage categories are used, due to different methodologies used by different countries simply due to different scope, different criterion for land quality, vegetation, the level of urbanization, that also depends on historical reasons and so on.
Briefly, and maybe more scientifically the concept is described in wikipedia.
Zoning was and still is made using logical methods, cartographically visualizing territory: overlaying many layers (GIS works here perfectly), analyzing and making deductions.
Nowadays, mathematical models are created to help to solve this ambiguate problem.
One of a quantitative methods for zoning protected natural areas are presented in argentinians paper (Verdiell et all, 2003) that talks about model based on a simulated annealing algorithm.
Another well known computational method that is more and more used in landscape planning, is cellular automata (CA) (check wikipedia), that mostly helps to model the land use change or indeed to simulate the land use change.
Indeed, W. Tobler, the one who defined the first law of geography, was the first proposing to use cellular automata as a tool for modeling spatial dynamics.
