Determining the Level of Certainty in Finnish Soil Maps

摘要

The relevant issues about uncertainty in geographic information are being researched worldwide and the numbers of applications dealing with spatial data uncertainty increase every year. The subject is also widely discussed and being taken into consideration in Finland. The Ministry of Agriculture and Forestry, which concern is the geological information in Finland, committed a project to study the imprecision of soil data sets. In this paper the procedure of evaluating soil polygon boundaries is studied to model the imprecision in this process. Information is gathered from experts (among them are geologists, soil surveyors and soil scientists) by questionnaires and this information is used to construct a model to evaluate the unceitainty of the soil mapping process and its influence on uncertain boundaries in soil maps. There are many alternatives to study and indicate the uncertainty and certainty information of soil maps. From the authors' perspective based on previous research, there are some alternatives that can be taken into consideration including methods that relate to kriging interpolation for imprecise soil polygon boundaries, fuzzy soil maps and level of certainty of soil maps. In this paper, we focus on the level of uncertainty of soil maps based on the variables from the soil mapping process. To get a certainty measure on soil maps we identified and included several variables into our model. The result will be an equation to calculate the level of estimated certainty of soil maps.