Management effects on soil C storage on the Canadian prairies

Journal Article · Mon Jul 06 04:00:00 EDT 1998 · Soil & Tillage Research

DOI:https://doi.org/10.1016/S0167-1987(98)00105-6· OSTI ID:1578150

Janzen, H H. ^[1]; Campbell, C A. ^[2]; Izaurralde, R Cesar C. ^[3]; Ellert, BH ^[1]; Juma, N G. ^[4]; Mcgill, William B.; Zentner, R P. ^[1]

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1. Agriculture and Agri-Food Canada
2. ROCKWELL HANFORD OPER.
3. BATTELLE (PACIFIC NW LAB)
4. University of Alberta

The Canadian prairie, which accounts for about 80% of Canada's farmland, has large reserves of soil organic carbon (SOC). Changes in the size of the SOC pool have implications for soil productivity and for atmospheric concentrations of CO2, an important `greenhouse gas'. We reviewed recent Ændings from long-term research sites to determine the impact of cropping practices on SOC reserves in the region. From this overview, we suggest that: (1) the loss of SOC upon conversion of soils to arable agriculture has abated; (2) signiÆcant gains in SOC (typically about 3 Mg C ha?1 or less within a decade) can be achieved in some soils by adoption of improved practices, like intensiÆcation of cropping systems, reduction in tillage intensity, improved crop nutrition, organic amendments, and reversion to perennial vegetation; (3) changes in SOC occur predominantly in `young' or labile fractions; (4) the change in SOC, either gain or loss, is of Ænite duration and magnitude; (5) estimates of SOC change from individual studies are subject to limitations and are best viewed as part of a multi-site network; and (6) the energy inputs into agroecosystems need to be included in the calculation of the net C balance. The long-term sites indicate that Canadian prairie soils can be a net sink for CO2, though perhaps only in the short term. These sites need to be maintained to measure the effects of continued agronomic evolution and predicted global changes.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1578150
• Report Number(s): PNNL-SA-42209
• Journal Information: Soil & Tillage Research, Journal Name: Soil & Tillage Research Journal Issue: 3-4 Vol. 48
• Country of Publication: United States
• Language: English

Related Subjects

Carbon
Greenhouse gas
Carbon dioxide
Tillage
Crop rotation
Fertilizer