HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in Web of Science Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (15) Citing Articles via Google Scholar Google Scholar Articles by Campbell, C. A. Articles by Zentner, R. P. Search for Related Content PubMed Articles by Campbell, C. A. Articles by Zentner, R. P. Agricola Articles by Campbell, C. A. Articles by Zentner, R. P. Related Collections Other Legumes Crop Rotation Systems Best Management Practices Dryland Cropping Systems Soil Organic Matter Other Oil Crops Tillage

Carbon Storage in Soils of the North American Great Plains

Effect of Cropping Frequency

^a Agric. and Agri-Food Canada, Cent. Exp. Farm, Ottawa, ON K1A 0C6, Canada
^b Agric. and Agri-Food Canada Res. Cent., Lethbridge, AB T1J 4B1, Canada
^c Dep. of Soil and Crop Sci., Colorado State Univ., Fort Collins, CO, 80523
^d Great Plains Syst. Res. Unit, USDA-ARS, P.O. Box E, Fort Collins, CO, 80522
^e Pollution Data Res., Environ. Canada, 851 St. Joseph Blvd., 9th Floor, Hull, QC K1A 0H3, Canada
^f Agric. and Agri-Food Canada Res. Centre, Swift Current, SK S9H 3X2, Canada

View larger version (28K): [in a new window]   Fig. 1. Changes in soil organic C in a Swinton loam at Swift Current, SK, after land that had been in fallow–wheat for 70 to 80 yr, with minimal N inputs and conventional tillage (CT), was converted to a continuous wheat (Cont W), fertilized, no-tillage (NT) system. (Note: Estimated initial soil organic C using adjacent fallow–wheat area gives poor estimate.) (Adapted from Campbell et al., 1995.)

View larger version (25K): [in a new window]   Fig. 2. Changes in soil organic C (SOC) in (a) 0- to 10- and (b) 0- to 20-cm depth over 12 yr as a function of site [potential evapotranspiration (PET)], slope, and cropping frequency in a no-till study in Colorado, USA. Soil organic C in the 0- to 20-cm depth in 1986 for the summit, sideslope, and toeslope positions was 21.9, 21.5, and 29.0 Mg ha–1, respectively, at Sterling; 25.1, 21.8, and 33.9, respectively, at Stratton; and 9.2, 12.6, and 21.4, respectively, at Walsh. (Note: In this and subsequent figures, cropping frequency for fallow–crop, fallow–crop–crop, fallow–crop–crop–crop, and continuous crop = 50, 66, 75, and 100%, respectively.) [From Sherrod et al. (2003) and unpublished data (2004).]

View larger version (29K): [in a new window]   Fig. 3. Effect of cropping frequency on soil organic C (SOC) trends (1967–1999) (a) in four monoculture wheat rotations and (b) in two continuous cropping rotations in Swift Current Old Rotation study (0- to 15-cm depth). (Adapted from Campbell et al., 2001b.) F-W = fallow–wheat, oat (hay)-W-W = oat (hay)–wheat–wheat, Flx-W-W = flax–wheat–wheat, Cont-W = continuous wheat, and W-Lent = wheat–lentil.

View larger version (14K): [in a new window]   Fig. 4. Effect of cropping frequency on soil organic C (SOC) trends (1967–1999) in 0- to 15-cm depth in Swift Current Old Rotation Study as estimated by model of Campbell et al. (2000a). Cont-W = continuous wheat, F-W-W = fallow–wheat–wheat, and F-W = fallow–wheat.

View larger version (30K): [in a new window]   Fig. 5. Change in soil organic C (SOC) (1967–1999) in 0- to 15-cm depth in Swift Current Old Rotation study, as measured and as estimated by the model of Campbell et al. (2001b). (All treatments receive N and P.) (Assumed SOC in 1967 = 30.5 Mg ha–1 as measured in F-W, which was rotation on test site during previous 70 yr.) (a) Effect of cropping frequency. (b) Effect of crop type. F-W = fallow–wheat, Cont-W = continuous wheat, F-Ry-W = fallow–rye–wheat, W-Lent = wheat–lentil, and F-Flx-W = fallow–flax–wheat.

View larger version (16K): [in a new window]   Fig. 6. Annual change in soil organic C (SOC) relative to continuous cropping with no-till on U.S. Great Plains (0- to 20-cm depth) (from Sherrod et al., 2003). (Note: The box plots show the median, quartiles, and extreme values in the data set. The box represents the interquartile range containing 50% of the values. The whiskers are lines that extend from the box to the highest and lowest values excluding outliers. The thick line across the box is the median.)

View larger version (19K): [in a new window]   Fig. 7. Annual change in soil organic C (SOC) relative to continuous cropping on conventional tillage as control: (a) Brown and Dark Brown Chernozems and (b) Black Chernozems and Gray Luvisols, in the Canadian Prairies.

View larger version (21K): [in a new window]   Fig. 8. Effect of cropping frequency on mean annual rate of change in soil organic C (SOC) relative to well-fertilized continuous cropping, tilled treatments (control) in Canadian Prairie studies (developed from data in Table 5).

View larger version (45K): [in a new window]   Fig. 9. Effect of fertilizer N and P and cropping frequency on soil organic C (SOC) in 0- to 15-cm depth, measured in a Black Chernozem at Indian Head, SK, in 1987 after 30 yr of conventional tillage and again in 1997, 7 yr after conversion to no-tillage management and increased rates of N (from Campbell et al., 2001a). F-W = fallow–wheat, F-W-W = fallow–wheat–wheat, and Cont W = continuous wheat.

View larger version (15K): [in a new window]   Fig. 10. Effect of cropping frequency on soil organic C in 0- to 15-cm depth in the Old Rotation Experiment at Swift Current, SK (1967–1999)—simulation with Century Model. F-W = fallow–wheat, F-W-W = fallow–wheat–wheat, and Cont W = continuous wheat.

View larger version (19K): [in a new window]   Fig. 11. Effect of cropping frequency on rate of change in soil organic C (SOC) (0- to 15-cm depth) in well-fertilized treatments of the Old Rotation Experiment at Swift Current, SK, during 1967–1999 (adapted from Campbell et al., 2001b).