Management › Tillage › Tillage system → Properties › Biology › Plants

Reduced tillage → Aboveground biomass

The studies disagree

43 %

of 7 studies with a clear result report a significant decrease

-3 %

typical change (7 studies with numbers)

studies · 9 findings

Count each study by

7 studies · 9 findings

What the studies show

3 of 7 studies report a significant decrease (43 %, 95 % confidence interval 16–75 %).

By the direction of each study’s results, significant or not: 2 of 6 studies with a direction point up (33 %, 95 % confidence interval 10–70 %; sign test p = 0.688).

↑ 2 increase
↓ 3 decrease
= 2 no effect

How large: typically -3 % (middle half -17 % to +7 %), from 7 studies with numbers
Basis: 7 studies, 9 findings; 0 entered by hand, 7 read by the library

Every study counts once, however many findings it reports: one with 40 sampling dates does not outvote ten others. A study with a significant increase and decrease (say at different depths) counts as "both". A first synthesis for orientation, not a substitute for a systematic review.

Where the studies are

goes up
stays the same
goes down
both ways

Through the soil profile

Each layer on its own: a study that reports the topsoil and the subsoil counts in both. Choose a layer to see what goes with it.

goes up
stays the same
goes down
both ways

In layers of unstated depth, aboveground biomass goes up in 29 % of the studies under reduced tillage, stays the same in 29 % and goes down in 43 %.

What makes a difference

The conditions whose levels differ most clearly, each with the outcome that differs most between its levels of at least 10 study layers. Choose a layer in the profile to see them for that layer alone, or a level here to filter by it.

Testing every condition on every study layer…

Along the conditions

Testing every condition on every study layer…