Article
The Breath of Life in Your Fields
by Dr Ash Martin PhD BSc(For)Hons
Think of your soil as a living, breathing thing, and how much it “breathes” (soil respiration) is a good sign of how healthy it is. This study dug into what makes some soils breathe more than others in our fields.
What they did: Scientists took soil samples from different spots in soybean, alfalfa, and corn fields – tops of hills, slopes, and bottom areas. They looked at a bunch of things in the soil and how much it was breathing. Then, they used a fancy computer program to figure out what the most important things were.
What they found:
- Topsoil breathes more: The top layer of soil (0-5 cm) generally showed more “breathing” than the deeper layer (5-20 cm). This makes sense because that’s where a lot of the action is with roots and organic matter.
- What you plant matters: Soybean fields seemed to have soil that “breathed” more. Different crops have different effects on the soil life.
- Where you are on the slope counts: Soil at the top of the slope (“summit”) also showed higher respiration in this study.
- Key players in soil breathing: The most important things influencing how much the soil breathed were:
- How deep you go: As mentioned, topsoil is more active.
- Ammonia (NH4-N): This is a type of nitrogen in the soil.
- What crop is growing: Different plants, different soil life.
- Where you are on the hill: Slope position affects things like water and nutrients.
- Silt (the amount of fine stuff in your soil): More silt seemed to mean less breathing in this study.
- Other important things: Things like potassium, phosphorus, pH (how acidic or alkaline the soil is), how well the soil holds onto nutrients (cation exchange capacity), and how chunky the soil is (mean weight diameter) also had an impact. Soil breathing liked higher levels of these.
- Things that mattered less in this study: Surprisingly, things like organic matter and clay content didn’t seem to be the biggest drivers of soil breathing in this particular study.
What this means for you:
- Soil health is complex: It’s not just one thing that makes soil healthy. Lots of things work together.
- Soil “breathing” is a useful sign: While it’s not the whole story, how much your soil breathes can give you an idea of how active and healthy it is.
- Consider different parts of your farm: Soil health can vary across your fields depending on the crop you’re growing and even where you are on a slope.
- Keep an eye on your nutrients and pH: Making sure your soil has the right balance of nutrients and the right pH can help keep the soil life active.
- Don’t rely on just one test: Soil respiration is a good indicator, but it’s best to look at it along with other soil health tests to get a full picture.
In simple terms, this research highlights that healthy soil is a mix of the right biology, the right nutrients, and even the lay of the land. While measuring how much your soil breathes can be helpful, remember to look at the whole picture to make the best decisions for your farm.
> 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:
Adhikari et al. (2023). Identifying key factors controlling potential soil respiration in agricultural fields.
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