Like many other substances that scientists want to study, soils vary greatly and thus present many challenges in measuring them. In fact, the lack of homogeneity is the greatest problem in measuring and analyzing soil.
Every time a scientist collects a sample of soil, that sample is only a small part of a much greater area of soil. The components tend to differ substantially, and as a result, accurate analysis is difficult. The scientist can measure the soil with significant accuracy, despite the difficulties. But in doing so, they need to keep several things in mind.
First, the scientist needs to have knowledge of how diverse the soil is. They must also understand the differences to be expected in soil samples before performing their analysis. Second, scientists have to use high-quality sampling equipment in the proper manner. They must analyze their samples using correct methods. Third, statistical analysis must be extremely extensive. This process must be
used both in deciding how to sample the soil and in analyzing the soil samples. Scientists use a variety of different methods for collecting soil. Sometimes they will take the soil back to a laboratory, but at other times experiments will be performed on site to avoid removing the soil and potentially disrupting an ecosystem. | 
