Sampling and analysis or visual examination of soil to assess its status and use potential is widely practiced from plot to national scales. However, the choice of relevant soil attributes and interpretation of measurements are not straightforward, because of the complexity and site-specificity of soils, legacy effects of previous land use, and trade-offs between ecosystem services. Here we review soil quality and related concepts, in terms of definition, assessment approaches, and indicator selection and interpretation. We identify the most frequently used soil quality indicators under agricultural land use. We find that explicit evaluation of soil quality with respect to specific soil threats, soil functions and ecosystem services has rarely been implemented, and few approaches provide clear interpretation schemes of measured indicator values. This limits their adoption by land managers as well as policy. We also consider novel indicators that address currently neglected though important soil properties and processes, and we list the crucial steps in the development of a soil quality assessment procedure that is scientifically sound and supports management and policy decisions that account for the multi-functionality of soil. This requires the involvement of the pertinent actors, stakeholders and end-users to a much larger degree than practiced to date.

Soil quality – A critical review

Selecting biological indicators for monitoring soils: A framework for balancing scientific and technical opinion to assist policy development

Soil quality is threatened by the increase in human population and by the fact that most of the cultivable land is intensively used. The initial interest in this topic focused on defining soil quality but shifted into how to measure soil quality in the late 1990s. There is a general agreement that soil biochemical, microbiological and biological properties are more suitable than physical and/or chemical properties for the purpose of estimating alterations in soil quality and hence soil degradation. To date, most studies have used microbial biomass, soil respiration and enzymatic activities to obtain soil quality indices, whereas less focus has been given to soil fauna (microarthropods and nematodes). This article aims to do a critical review of soil quality indices based on soil biological and biochemical activities, mainly microbial biomass, soil respiration and the activity of several enzymes. Limitations within the database of articles that are focussed on broad scale application of soil quality indices include the difficulty of selecting the highest quality soils for comparison purposes, lack of standardisation of analytical methods, and inclusion of an insufficient number of soil types and ecosystems. There is a need to validate soil quality indices, both, spatially and temporally and to explore the use of indices that integrate faunal and microbial measurements

Biological Indices for Soil Quality Evaluation: Perspectives and Limitations

Tillage-induced changes in the functional diversity of soil biota – A review with a focus on German data

Human societies rely on the vast diversity of benefits provided by nature, such as food, fibres, construction materials, clean water, clean air and climate regulation. All the elements required for these ecosystem services depend on soil, and soil biodiversity is the driving force behind their regulation. With 2010 being the international year of biodiversity and with the growing attention in Europe on the importance of soils to remain healthy and capable of supporting human activities sustainably, now is the perfect time to raise awareness on preserving soil biodiversity. The objective of this report is to review the state of knowledge of soil biodiversity, its functions, its contribution to ecosystem services and its relevance for the sustainability of human society. In line with the definition of biodiversity given in the 1992 Rio de Janeiro Convention1, soil biodiversity can be defined as the variation in soil life, from genes to communities, and the variation in soil habitats, from micro-aggregates to entire landscapes.

https://hal-bioemco.ccsd.cnrs.fr/bioemco-00560420/document

Enrico Mozzanica

Papers

Microarthropod communities as a tool to assess soil quality and biodiversity: a new approach in Italy