ABSTRACT
Monitoring ecosystem components is essential for acquiring basic data to assess the impact of land-management systems and to plan resource conservation. For this reason, soil scientists have always sought to link soil type and soil variables to potentials or limitations of land use. During the last decade, numerous authors have highlighted a fourth soil function, indicating that soil represents one of the leading reservoirs of biodiversity, as reported by Menta. All these authors relate these soil functions to the need to identify soil-quality indicators (SQI). SQI indices are needed to identify problem production areas, to make realistic estimates of food and natural resource production, to monitor changes in sustainability and environmental quality as related to agricultural and forest management, and to assist national and state or regional agencies in formulating and evaluating sustainable agricultural and forest land-use policies.
