Student Conceptions of Biogeochemical Cycles and the Earth System

Biogeochemical cycles are an important component of Earth systems thinking.  Often, it is assumed that students understand the cycling of elements carbon, nitrogen, and phosphorus from high school, and these cycles are not explicitly taught.  This work took a largely qualitative approach using both interviews and drawings to understand undergraduate students' mental models of these cycles.  Initial work has found that across disciplines, students tend to hold relatively simplistic mental models of these cycles that tend to be related only to short-term biotic parts of these cycles (i.e. photosynthesis and respiration in the the carbon cycle).  This work demonstrates the importance of explicitly teaching biogeochemistry as well as systems thinking skills across disciplines.  This work also revealed an lack of conception of the role of the hydrosphere in any of these cycles.  One study based on this work is currently in revision for the Journal of Research on Science Teaching.  A second paper based on systems component present in drawings is in preparation potentially for Biogeosciences.