Evaluation of point-scale assessments of soil quality

ABSTRACT:

This study was conducted to evaluate four approaches to point-scale assessment of soil quality: farmers' perceptions and field-descriptive, field-analytical and laboratory-analytical assessments. Twenty-four conventional and organic farmers were paired within ecoregions, and perceptions of soil quality indicators on their “good” and “problem” soils were surveyed. Using results from laboratory-analytical assessments as a standard, farmers' perceptions were accurate or near-accurate in over 75% of the cases for the majority of indicators evaluated in the study. Field-descriptive assessments of topsoil depth and soil texture were accurate or near-accurate in at least 92% of the cases. Results from field-analytical assessments of electrical conductivity, soil pH, and soil nitrate were accurate in at least 46% of the cases. From an assessment-efficiency standpoint, seeking out farmers' perceptions of soil quality indicators seems to be an appropriate first iteration to point-scale evaluations.