Concepts of Soil Mapping and Interpretation

Fuzzy soil mapping based on prototype category theory

“…Although soils have been traditionally mapped as discrete polygons, it has long been recognized that soil classes have indeterminate boundaries in both geographic space and attribute space (Burrough, 1996). In the mapping of soil polygons in terms of soil-landscape units (Hudson, 1990), definitions have always been relative, as in a convex (versus concave) position or steep (versus not steep) slopes. Prototypes may change and criteria for determining memberships evolves through years of field work by experiencing more and more real instances of a soil category.…”

Effects of variable attribute weights on landform classification

“…Simple GIS overlay of digital terrain data or remotely sensed vegetation data with digital soil maps often results in poor estimates of the co-occurrence of these variables.' However, it is still reasonable to assume the existence of inherent linkages, as well as certain spatial correlations, between landform classification and soil maps, because soil map production relied heavily on the traditional soil-landscape model (Soil Survey Staff, 1951, 1999Hudson, 1990Hudson, , 1992. Figure 3 shows the results of comparing the soil map (Figure 1(b)) and landform classification maps (Figure 1(c)).…”

Toward Accurate and Reliable Soil Surveys

“…Data Analysis Hudson (1990) believes that there is a widespread feeling within our profession that something is fundamentally wrong with soil maps and no one can figure out how to fix it. Is there a possibility that there is nothing wrong with soil maps and the perception that there is a problem is a result of a poor conceptual model of how we interpret map units?…”

“…One symptom of this problem is the obsession with variability in map units. Recently, no technical meeting has been complete without a discussion of transects and new computer programs to calculate statistics (Hudson, 1990).…”