The contribution of the soil biophysical properties to the management of temperate agrosystems

THE CONTRIBUTION OF THE SOIL BIOPHYSICAL PROPERTIES TO THE MANAGEMENT OF TEMPERATE AGROSYSTEMS Several studies point to the influence of soil aggregation on microbial communities and their activities. The soil aggregates, or more in detail their pores are habitats where microorganisms live and biogeochemical processes occur. The most widely used traditional approaches for the aggregates separation are based on the wet sieving or on density fractionation. On the obtained aggregate fractions it is then possible to determine the microbial biomass functionality. In contrast with the standard methods, in this project we will study fractions of macro and microaggregates separated on the base of the different breakdown mechanisms induced by water. The goal is to identify and to test biophysical, innovative and effective indexes for the assessment of the maintenance or improvement of soil quality induced by different management procedures, in forest and agricultural ecosystems. More in detail, for the forest ecosystem the study concerns an oak wood and an alfalfa grassland located in the Apennine mountain belt, while for the agricultural ecosystem agrarian sites differently managed for their fertility will be considered in Bologna plain. For both ecosystems the main pools of organic matter and microbial activity will be investigated both in soils and in aggregate fractions. The microbial activity evaluation concern the quantification of extracellular enzyme activity using fluorimetric assays in microplate scale. The obtained data will be related to the data of the aggregates stability and soil porosity in order to identify the representative parameters of soil quality and, therefore, the useful indicators for the assessment of the soil quality changes caused by the different management.