Calorimetry and soil

This paper is a review about the application of calorimetry to study soil properties and its metabolism. Although this research has increased slowly but continuously during the last 30 years, it is true that it has received poor attention. One reason for that could be the complexity of the soil and the difficulties to investigate it from a thermodynamic point of view. In this paper we would like to demonstrate that calorimetry constitutes a very suitable method to face the main topics related to soil quality and activity. Very well known indicators used in soil research can be measured by different thermal and calorimetric methods such as differential scanning calorimetry (I)SQ, thermogravimetry (TG) and isothermal calorimetry (ITC). TG and I)SC are both temperature scanning methods used for estimation of certain properties of the soil material such as organic matter, ignition temperature, humification index, quartz content, so on, whereas the study of the soil microbial metabolism is conducted under essentially isothermal conditions by ITC. In this review, the contributions of these techniques to different topics in soil research are described and their importance for the environmental concern is discussed in the light of this new era. (C) 2007 Elsevier B.V. All rights reserved.