Jacqueline Baar

Series: Environmental Science, Engineering and Technology
BISAC: SCI026000

The interest in maintaining and increasing biodiversity has increased worldwide since The Treaty on Biological Diversity of Rio de Janeiro in 1992. This century, awareness of sustainability has grown too. The awareness of biodiversity and sustainability is not only focused on the above-ground environment, also the below-ground soil environment is considered. The soil environment occurring globally provides services that humans draw from nature. The so-called ecosystem services include products like food and processes like nutrient transfer. Numerous people consider the ecosystem services as public benefits contributing to welfare for free and infinitely available. The ecosystem services have considerable economic value and the consideration on this value is growing.

However, the services provided by the soil can be used within certain conditions for sustainability reducing the risks of irreversible changes. Durable and sustainable soil ecosystem services have more economic value, certainly on the long term, than those services used for welfare without any consideration for the environment and biodiversity. Sustainable soil ecosystem services require a good soil quality integrating the physical, chemical, and biological components of soils and their interactions. This implies elimination of soil degradation, reduction of input of chemical fertilizers and crop protection agents as well as decrease of dehydration of soil and management of beneficial soil organisms. A good soil quality determines agricultural sustainability, environmental quality and, consequently, plant, animal and human health. For such good soil quality, knowledge is needed on the contribution of soil-organisms to durable and sustainable soil. Mycorrhizal fungi are an important group of the soil-organisms being beneficial to sustainable soils.

These soil fungi live in symbiosis with the great majority of plants, trees and crops. Evidence is growing that mycorrhizal fungi enhance the plant health and crop yield. The efficacy of mycorrhizal fungi vary with abiotic factors including soil type and structure. In this paper, the efficacy of mycorrhizal fungi in relation to abiotic factors will be presented based on recent data. Preconditions on the soil characteristics for sustainable soils of good quality and for optimal development of mycorrhizal fungi are provided. The economic value of optimal mycorrhizal fungal development is shown and related to soil ecosystem services. European policy makers are working on legislation for soil protection and management.

The European Commission has proposed a Soil Framework Directive to address soil degradation across the European Union, and to repair the damage that has already been done. Indicators for soil quality could contribute to monitoring the condition of soils when reflected in standards, like soil quality metrics. Mycorrhizal fungi are indicative for changes in soils being sensitive to changes in the physical-chemical conditions of the soil. In this book, it is shown that mycorrhizal fungi are reliable and sensitive indicators for disturbances in the soils to be used for the development of soil quality metrics. Different soil quality metrics with different categories ranging from very bad to very good are described based on a considerable number of root samples. The applicability of the soil quality metrics is discussed and their potential usefulness for the legislations for protection of soil quality is shown. (Imprint: )