DECOMPOSITION RATE IN THE FOREST OF SCHOOL YARD: A DIDACTIC INTERVENTION

Abstract

For the preparation of theoretical instruction of the concept of natural decomposition, and the teaching research through an annual project for the paper decomposition rate in soil, utilized, in a Lyceum, variety of teaching tools and techniques. For the demands of the teaching, was searched the synonymous and linked terms to decomposition and decomposers into the Curricula of the Lyceum Biological courses and textbooks. Papers, sealed in perforated plastic bags, buried in the soil periodically during the school year, and with their haul, dried, weighed and thus exported their weight reductions as result of the action of soil decomposers.During the decomposition are taking place many and varied changes relating to and affected by many factors. These are the effects particularly of the temperature influences the speed of the chemical reactions occurring in the degradable materials and on the microorganisms that carry out it, the effects of moisture, since water hydrolyzes biological macromolecules of the organic matter degraded to smaller, and generally any changes in the structure and synthesis of the molecules of the decomposing organic materials. The rate of reduction of the initial paper weight shows that cellulose degradation has different rates in different seasons. Decomposition was faster in the early autumn, when drought ceased to be a limiting factor and in late spring when the temperature no longer was a limiting factor. In Mediterranean climates, like Crete, where the sun and wet winters alternating with warm, long and dry summer, intense decomposing activity observed at the time of the high temperature associated with water availability, high soil moisture, and even the moisture preceded, that the chemical bonds in molecules of paper cellulose to weaken and break down readily.