Soil microorganisms are both components and producers of soil organic carbon, a substance that locks carbon into the soil for long periods. Abundant soil organic carbon improves soil fertility and water-retaining capacity. There is a growing body of research that supports the hypothesis that soil microorganisms, and fungi in particular, can be harnessed to draw carbon out of the atmosphere and sequester it in the soil.
Soil microorganisms may provide a significant means of reducing atmospheric greenhouse gasses and help to limit the impact of greenhouse gas-induced climate change.
We can see that healthy soils contain enormous numbers of microbes and substantial quantities of microbial biomass. The potential for activity must be stressed because, under normal situations, the microbial population does not receive a constant supply of readily-available substrates to sustain prolonged high rates of growth.
Almost all soil organisms except some bacteria need the same things that we need to live: food, water and oxygen. They eat a carbon-based food source, which provides all their nutrients, including nitrogen and phosphorus. They require a moist habitat, with access to oxygen in the air spaces in soil.
These reasons explain why 75 per cent of soil organisms are found in the top five centimetres of soil. It also explains, however, why many of our agricultural soil microorganism populations are depleted. Unfortunately, some of the agricultural practices that were standard in Australia up until the s, such as excessive land clearance, the burning of stubble, inappropriate fertiliser application and over-tillage, have degraded soils and produced conditions such as salinity, acidification, soil structural decline and desertification.
While in many areas, our agricultural soils are still considered to be under threat, in recent decades, changes to the farming practices detailed above are helping to create healthier soils. Until recently, this was considered the only way to improve biological fertility.
Creating the right conditions and microbes will come and, alternatively, if the conditions are not correct, efforts to introduce beneficial microbes are doomed to fail. Recently, however, scientific research has achieved significant success in the inoculation of soils and seeds with beneficial bacterial and, in particular, mycorrhizal fungi to improve yields and to promote healthier soils.
While still in an early stage of development, field trials have been positive and may, in the future, lead to a wide range of benefits based upon improved soil biological fertility. In the past, soil microbiological science has focussed upon the harmful or pathogenic threat posed by a small number of soil-dwelling microorganisms. This is has skewed our understanding away from most of soil microorganisms that pose no threat to human health or to agricultural production and that perform essential roles in mechanisms that are fundamentally important to the sustainability of human civilisation and life on the planet generally.
This emphasis, however, is changing. Interdisciplinary soil research of the future must acknowledge a dynamic region of interacting processes: the holistic nature of living soil and that this portion of soil itself is but a part of a greater soil system. By using integrative methods including non-destructive imaging, next-generation chemical analysis with substantial space and time resolution, and simulation modelling, the secrets of the dynamic soil and biological relationship will be revealed.
Holistic soil science has the potential to substantially increase understanding of plant-soil systems and provide guidance for pressing issues of the 21st century, such as agricultural sustainability and environmental change.
Print Email. Key Points Fertile soils teem with microorganisms, which directly contribute to the biological fertility of that soil.
Biological fertility is under-studied and our scientific knowledge of it is incomplete. In addition to fertility, soil microorganisms also play essential roles in the nutrient cycles that are fundamentally important to life on the planet.
In the past, agricultural practices have failed to promote healthy populations of microorganisms, limiting production yields and threatening sustainability. Scientific research is exploring new and exciting possibilities for the restoration and promotion of healthy microbial populations in the soil. Definition Soil microbiology is the study of organisms in soil, their functions and how they affect soil properties.
Some of the functions performed in soil by fungi are: Decomposers — saprophytic fungi — convert dead organic material into fungal biomass, carbon dioxide CO 2 , and small molecules, such as organic acids. Mutualists — the mycorrhizal fungi — colonise plant roots. In exchange for carbon from the plant, mycorrhizal fungi help to make phosphorus soluble and bring soil nutrients phosphorus, nitrogen, micronutrients and, perhaps, water to the plant.
One major group of mycorrhizae, the ectomycorrhizae , grow on the surface layers of the roots and are commonly associated with trees. Here, some highlights. Microbes play defense. The oodles of microbes that live on and inside us protect us from pathogens simply by taking up space. By occupying spots where nasties could get access to and thrive, good microbes keep us healthy.
Microbes boost the immune system. Researchers at Loyola University demonstrated in a study how Bacillus, a rod-shaped bacteria found in the digestive tract, bind to immune system cells and stimulate them to divide and reproduce.
The research suggests that, years down the road, those with weakened immune systems could be treated by introducing these bacterial spores into the system. These microbes could potentially even help the body fight cancerous tumors. Microbes protect us from auto-immune diseases. Boost biogas production. Main menu. English EN. Microbes Microbes do more Microbes are microscopic, single-celled organisms like bacteria and fungi.
Future proof with innovation Although miniscule, microbes have the power to solve daunting global challenges and unlock new ways we can work towards a greener future. By using biology, we can make a sustainable difference together. Millions of years of mutual benefits Essential. Our solutions Tiny powerhouses Crop protection, sustainable farming, wastewater treatment and environmentally-friendly cleaning solutions. Healthier harvests. Poultry power. Fitter fish. Crystal clear. Bacteria More than just pathogens - can be friend or foe.
Viruses Smallest of all the microbes, but are they alive? Fungi More than just mushrooms. Protozoa Microbes with a taste for poo and so much more. Algae Microbial powerhouses essential for life.
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