Management › Tillage › Tillage system → Properties › Chemistry › Nitrogen compounds › Total Nitrogen › Total dissolved Nitrogen

Reduced tillage → NO3-/Nitrate

A clear tendency, not consistent

71 %

of 7 studies with a clear result report a significant increase

+42 %

typical change (5 studies with numbers)

studies · 7 findings

Count each study by

7 studies · 7 findings

What the studies show

5 of 7 studies report a significant increase (71 %, 95 % confidence interval 36–92 %).

By the direction of each study’s results, significant or not: 6 of 7 studies with a direction point up (86 %, 95 % confidence interval 49–97 %; sign test p = 0.125).

↑ 5 increase
↓ 1 decrease
= 1 no effect

How large: typically +42 % (middle half +15 % to +101 %), from 5 studies with numbers
Basis: 7 studies, 7 findings; 1 entered by hand, 6 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…