Category: Blog

The Real Benefits of Digital Soil Mapping

Proponents of digital soil mapping sometimes criticize traditional soil mapping for using a discrete data model to describe a continuous surface (field) and lacking a quantified estimation of error. Although most of my research is on digital soil mapping, I like to give due credit to the accomplishments of traditional soil mapping. I understand the need for … Continue reading The Real Benefits of Digital Soil Mapping

Types of Measurement Error

We always want to avoid error, but it is a fact of life. At the foundation of analysis and modelling, we rely on measurements. Because errors in measurements are inescapable, the important question is how much does the error affect the result? I start the conversation by explaining what measurement error is, including its component parts, and what we can do to minimize its effect.

CLORPT: Spatial Association in Soil Geography

From as early as 500 BCE, humans have recognized that some things vary together in space. This is essentially correlation, but the spatial aspect sometimes adds a special twist. Also, correlation requires evaluation of quantitative data, while this concept is not limited to quantitative characteristics. For example, Diophanes of Bithynia observed that “you can judge … Continue reading CLORPT: Spatial Association in Soil Geography

Colluvium vs Alluvium

UPDATE: The tremendous response to this blog post led to an international and interdisciplinary survey on how these terms are/should be defined. The results of that survey were combined with an in-depth review of the literature to produce an article that has now been published in Earth-Science Reviews. The article updates and refines the patterns … Continue reading Colluvium vs Alluvium

Fundamentals of Spatial Prediction

In the process of creating a map, geographers often have to engage in the activity of spatial prediction. Although there are many tools we use to accomplish this task, they generally boil down to the use of one or two fundamental concepts. Waldo Tobler is credited for identifying the ‘first law of geography’, stating “Everything … Continue reading Fundamentals of Spatial Prediction