In search of biological indicators for soil health
Soil health is compared to soil qualtiy and defined as "The capacity of a soil to function within ecosystem boundaries to sustain biological productivity, maintain environmental quality, and promote plant and animal health” (Doran et al., 1996).
The function of soil is: life support processes, i.e. plant anchorage and nutrient supply, water retention and conductivity, support of soil food webs, and environmental regulatory functions. For example; nutrient cycling, source of microbial diversity,
remediation of pollutants, and sequestration of heavy metals. Therefore you can associate health of soil to biological diversity and stability. Stress can affect the health and this may result in diseases.
This study tries to find indicators that can define soil health. Besides that the relationship between disease suppression and soil health will be discussed.
It is said that "a healthy soil is a stable soil". Ecosystem stability has been related to biodiversity and resilience in response to stress. Stress tolerance means that soil has buffering capacity and the ability to regenerate. There are 3 kinds of stress factors: physical, chemical, and biological. The researchers will further discuss these factors and there influence.It is said that "a healthy soil is a stable soil". Ecosystem stability has been related to biodiversity and resilience in response to stress. Stress tolerance means that soil has buffering capacity and the ability to regenerate. There are 3 kinds of stress factors: physical, chemical, and biological.
Biodiversity refers to a variaty of groups like bacteria, fungi, protozoa, nematodes, earthworms and arthropods. The researchers suggest that indicators of soil health could be found by monitoring responses of the soil microbial community to the application of different stress factors. Disease suppression can be viewed as a manifestation of ecosystem stability and health. Thus, indicators for soil health could possibly also function as indicators for disease suppressiveness.
The article shows that there are parallels between the search for indicators of soil health and disease suppression. However the results are very difficult to interpret. Therefore, the researchers suggest a more systematic approach to the search of indicators for soil health and disease suppression for a even better review.
> From: Bruggen et al., Applied Soil Ecology 15 (2000) 13-24. All rights reserved to Elsevier B.V.. Click here for the online summary.
