Soil can now be tested for microbe activity. The ability to determine the “health” of a field’s soil is a recent and exciting opportunity. Knowing the biological short falls allows us to change our farming practices to enhance plant and soil fertility and add nutrients more cost effectively.
Farming can destroy soil’s rhiziobiome (microbial ecosystem) by using soil amendments such as fertilizer and pesticide without consideration for their effects. By contrast, healthy soil can increase fertility in multiple ways including supplying nutrients such as nitrogen and protecting against pests and disease while reducing the need for water and other inputs. Some approaches may even allow agriculture in soils that were never considered viable.
Soil microbiology is the study of organisms in soil, their functions, and how they affect soil properties. Microorganisms in soil are important because they affect soil structure and fertility. Microbes can make nutrients and minerals in the soil available to plants, produce hormones that spur growth, stimulate the plant immune system and trigger or dampen stress responses. In general, a more diverse soil microbiome results in fewer plant diseases and higher yield.
Soil microorganisms can be classified as bacteria, actinomycetes, fungi, algae and protozoa. Each of these groups has characteristics that define them and their functions in soil.
One of the most distinguishable features of bacteria is their biochemical versatility. A bacterial genus called Pseudomonas can metabolize a wide range of chemicals and fertilizers. Bacteria are also responsible for the process of nitrogen fixation, which is the conversion of atmospheric nitrogen into nitrogen-containing compounds (such as ammonia) that can be used by plants.
Actinomycetes are soil microorganisms. They are a type of bacteria but they share some characteristics with fungi. One of the most notable characteristics of the actinomycetes is their ability to produce antibiotics. Streptomycin, neomycin, erythromycin and tetracycline are only a few examples of these antibiotics.
Fungi are important in the soil as food sources for other, larger organisms, pathogens, as well as providing beneficial symbiotic relationships with plants or other organisms and in this fashion can effect the overall soil health. The quality as well as quantity of organic matter in the soil has a direct correlation to the growth of fungi due to the fact that most fungi consume organic matter for nutrition.