Management → Properties › Physics

Organic farming → Bulk density

A clear tendency, not consistent

25 %

of 4 studies with a clear result report a significant increase

+5 %

typical change (3 studies with numbers)

studies · 4 findings

Count each study by

4 studies · 4 findings

What the studies show

1 of 4 studies report a significant increase (25 %, 95 % confidence interval 5–70 %).

By the direction of each study’s results, significant or not: 2 of 3 studies with a direction point up (67 %, 95 % confidence interval 21–94 %; sign test p = 1).

↑ 1 increase
↓ 1 decrease
= 2 no effect

How large: typically +5 % (middle half -0 % to +8 %), from 3 studies with numbers
Basis: 4 studies, 4 findings; 0 entered by hand, 4 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

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…