You do not need perfect measurement to notice whether a soil is becoming more alive.
Common signs include:
- soil that smells earthy rather than sour or stale
- more crumb structure and less hard setting
- better water infiltration
- mulch breaking down steadily
- more worms, fungi, insects, and visible life
- roots moving more easily through the soil
- plants looking more resilient rather than just greener
You may also notice that the soil becomes easier to work over time and less extreme in wet-dry swings.
Healthy biology is usually a system response, not a single input response. Cover, roots, organic matter, moisture, and reduced disturbance all help.
The simplest useful question is: **Is this soil becoming easier for life to inhabit?**