Resumen
This paper analyzes the impact of fieldwork on the development of students? mental models concerning glaciers and their effects on the landscape. Data were collected by means of an open-ended questionnaire that was administered to 279 pre-service teachers before and after an educational field trip, which analyzed its impact on short-term and long-term outcomes. In general, students? mental models about how glaciers function and how they create landforms are relatively simplistic and incomplete. Students are unaware of the major erosional properties associated with glaciers and many of them do not specify that glaciers are bodies of ice that have a tendency to move down slope. The analysis of the data yielded four mental model categories. Fieldwork influenced the short-term effects on mental model development even though its positive impact decreases over time. Mental models including scientific views were only found in the post-instruction group. On the other hand, the pre-instruction group was strongly influenced by a catastrophic event that occurred in the region in 1959 (the Ribadelago flooding), which interferes with students? mental reasoning on the formation of landscape features. This way of thinking is reinforced and/or mixed with a religious myth (Villaverde de Lucerna legend), which also invokes a catastrophic origin of the lake. In this case, this includes mystic flooding.