Agronomy Library > Soil Conservation

Direct Seeding and Soil Quality
Author: Reduced Tillage LINKAGES
Date Created: May 13, 2002
Last Reviewed: February 01, 2007

The practice of direct seeding presents unique opportunities for soil quality enhancement. Some of these are:
 
Increases organic matter and thereby soil quality.
 
Changes in Organic Matter under Direct Seeding System
Year
Percent Organic Matter
Direct Seed
Conventional
0
4.0
4.0
5
4.5
4.0
10
5.0
4.0
                Source: Agriculture-Agri-Food, Lethbridge Research Station
 
Improves seedbed moisture – In direct seeding systems 80-100% of crop residue is left on the soil surface. This residue acts as a sponge for water to soak into the soil surface, thereby improving the soil moisture availability to the germinating crop.
 
Location
Previous Crop
Seedbed Moisture (0-15 cm)
Zero-till
Conventional
Tisdale, SK
Barley
5.4
4.9
Vauxhall, AB
Wheat
4.7
4.2
Lethbridge
Wheat
6.1
4.7
Rolla, B.C.
Barley
9.4
8.6
 
Improves water infiltration after soil reaches its maximum water holding capacity. Recent research has shown that direct seeding systems have more magapores due to increased earthworm activity and root channels, resulting in better water infiltration to the soil profile.
 
Changes in Water Infiltration Rate under Direct Seeding System
Year
Total infiltration* at I hour
Zero-till
Conventional
5
2.1
1.5
10
2.5
1.5
13
2.7
1.5
 
 
 
·          3.2 inches of water was applied in 1 hour.
 
Improves soil structure, tilth and reduces soil compaction.
 
Reduces erosion potential – crop residues on the soil surface protect the soil against wind and water erosion. Crop residues also hold the soil and associated nutrients (phosphorus) and pesticides, thereby reducing pollutant loads in the runoff and ultimately in surface water.