Article
Tiny Life a Big Driver
by Dr Ash Martin PhD BSc(For)Hons
Think of soil “breathing”(respiration) as a vital sign of its overall health and how well it supports your crops. This study looked at what things in the soil are most important for this “breathing” and why it’s crucial for everything your farm does. Healthy soil breathing means good nutrient cycling, which feeds your plants and provides them with more carbon to turn into sugar through photosynthesis.
What they did: Scientists set up mini-soil experiments in the lab using two different soil types – one with more clay and one sandier. They also added different fertilisers and then measured how much the soil breathed. They looked at things like the amount of clay in the soil, the nutrients available, and the types and amounts of tiny living things (microbes like bacteria) in the soil. Then, they used some fancy maths to figure out which of these things had the biggest impact on soil breathing.
What they found:
- Clay, nitrogen, and the amount and variety of bacteria are key: The amount of clay in the soil, the amount of soluble nitrogen (the kind plants can easily use), and how many bacteria were present, along with the variety of those bacteria, were all important in how much the soil breathed. These things together explained over 60% of the differences in soil breathing they saw.
- The tiny life in your soil is a big driver: When they looked at the bigger picture, the microbes (especially the bacteria) were the biggest reason why some soils breathed more than others. They contributed about 31% to the soil breathing.
- Soil texture (like how much sand or clay) also matters: The physical makeup of the soil, especially how much clay it had, was the next most important factor, contributing about 20% to soil breathing.
- The soil itself is more important than just adding fertilisers: The natural characteristics of the soil (like its texture and the microbes already living there) had a bigger impact on soil breathing than just adding fertilisers.
What this means for you:
- Healthy soil is alive! The tiny organisms in your soil are doing a lot of work, and their activity (which we see as soil “breathing”) is vital for healthy soil and good plant growth.
- Clay can be your friend (to a point): Soils with more clay tend to have more activity, which leads to more soil breathing.
- Nitrogen needs to be balanced: Having enough usable nitrogen is important for soil life activity.
- A diverse community of soil microbes is a good thing: Just like a diverse farm is often more resilient, a variety of bacteria in your soil helps keep things active and healthy.
- Focus on building healthy soil: This study highlights that the inherent qualities of your soil and the community of microbes living there are really important for soil health and productivity. While fertilisers play a role, focusing on building good soil structure and supporting a thriving soil microbiome can have a big impact.
In simple terms, this research shows that the living things in your soil, especially bacteria, are a major engine for soil health. The type of soil you have (sandy or clay-rich) also plays a significant role. Taking care of your soil’s natural health and the community of microbes living there is key for good nutrient cycling and productive crops.
> Try it out!: Our Microbe Activity Wise and Microbe Activity Wise Pro tests measure your soil’s potential microbial activity using respiration. The Pro version includes estimates of potential nitrogen and phosphorus availability.
Read the in-depth article:
Zou et al. (2024). Factors Driving Soil Respiration Rate After Different Fertilisers Sources Addition. Agronomy. 14 (11): 2468.
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