MAPPING THE ECOLOGICAL STRUCTURE OF A TERRITORY - A CASE-STUDY IN MADRID (CENTRAL SPAIN)

A procedure to map the ecological structure of a territory is shown. T he ecological structure is considered to be the result of the spatial coincidence of numerous physical and biological variables and the spat ial connections between territorial sectors. The spatial correspondenc e patterns of such Variables and sectors are detected by multivariate ordination analyses and were mapped using trend surface analysis (TSA) . According to these premises an ecological map of the Madrid area was designed. This ecological map is objective: its characteristics do no t depend on decisions by the specialists who compile it. The informati on it contains is based on the systematic analysis of the spatial rela tionships between numerous variables and territorial sectors. The use of TSA allows a synthesis of the way in which general gradients easily show the ecological spatial variability of the territory (low degree polynomials) or a superimposed-cellular or equipotential-structure app ears on those gradients (high degree polynomials). The usefulness of t he map is that it shows the ecological structure of the territory and the spatial linkages between the elements of this structure. The accur acy of the map showing these relationships may be ascertained by the f it to trend surfaces of increasing degree. The test was considered to be satisfactory as the results agreed with the prior ecological descri ptions of the area. The procedure is thus deemed applicable to lesser known areas and can be very useful in planning studies.