- Authors:
- Harker, K. N.
- Beckie, H. J.
- Blackshaw, R. E.
- Upadhyay, B. M.
- Smith, E. G.
- Clayton, G. W.
- Source: Canadian Journal of Plant Science
- Volume: 86
- Issue: 4
- Year: 2006
- Summary: Integrated weed management (IWM) systems that combine seeding date, seeding rate, herbicide rate, and timing of nitrogen (N) fertilizer application were assessed for their economic performance in the Dark Brown and Black soil zones. A barley-field pea IWM system in the Black soil zone at Lacombe, Alberta, and a wheat-canola IWM system in the Dark Brown soil zone at Lethbridge, Alberta, and Scott, Saskatchewan, were used to assess contributions of seeding date (April or May), seeding rate (recommended or 150% of recommended), fertilizer timing (fall or spring), and in-crop herbicide rate (50% or 100% of recommended). The factorial set of treatments was applied in 4 consecutive years at each site. For barley-field pea production, the highest contribution margin (CM) (returns over variable production costs) was earned with 50% of the recommended herbicide rate, spring application of N fertilizer, seeding barley later at the high seeding rate, and seeding field pea early at the recommended seeding rate. This IWM system had a CM benefit of at least $51 ha(-1) compared with current common practices. The wheat-canola system results were site specific. At Lethbridge, it was more profitable to use 50% of recommended herbicide rates and to seed both crops early, with an early seeding date being very important for canola. The CM of this IWM system was $48 ha(-1) higher than current common practices. At Scott, the wheat-canola system was more profitable with spring fertilizer application, 50% of the recommended herbicide rate, and an early seeding date for canola. The best IWM system had a CM $15 to $75 ha-1 higher, depending on the year, than common practices. Our results confirmed the economic merits of using IWM practices for cereal-oilseed and cereal-pulse cropping systems in these regions of western Canada.
- Authors:
- Schillinger, W. F.
- Wuest, S. B.
- Williams, J. D.
- Gollany, H. T.
- Source: Soil & Tillage Research
- Volume: 86
- Issue: 2
- Year: 2006
- Summary: Water erosion and runoff can be severe due to poor infiltration through frozen soil in the dryland wheat (Triticum aestivum L.) production region of the inland Pacific Northwest (PNW), USA. For more than 70 years, farmers and researchers have used various methods of subsoiling to reduce runoff and erosion and to improve infiltration and soil moisture storage. The practice and equipment have evolved from chiseling continuous open channels across hillslopes to the rotary subsoiler that pits the soil. Farmers often subsoil wheat stubble after harvest, but do not employ this practice on newly planted winter wheat fields. These fields are especially vulnerable to erosion because of meager residue cover after a year of fallow. A 6-year field study was conducted in eastern Washington to determine the effect of rotary subsoiling in newly planted winter wheat on over-winter water storage. erosion, infiltration, and grain yield. There were two treatments, rotary subsoiling and control. The rotary subsoiler created one 40 cm-deep pit with 4 L capacity every 0.7 m(2). Natural precipitation did not cause rill erosion in either treatment because of mild winters during the study period. Net change in water stored over winter was significantly (P < 0.05) improved with rotary subsoiling compared to the control in 2 of 6 years. Grain yield was not affected by treatments in any year or when averaged over years. In 2003, we simulated rainfall for approximately 3 h at a rate of 18 mm/h on both subsoiled and control plots to determine runoff and erosion responses on frozen soils. Rotary subsoiling reduced runoff (P < 0.01) by 38%. Rotary subsoiling also significantly reduced erosion (P < 0.01) during the 20-45 min period after runoff had begun. The total quantities of eroded soils were 1.3 and 3.4 Mg/ha for the subsoiled and control treatments, respectively, with inter-rill the dominant erosion process. The average infiltration rate for the control treatment (3.3 mm/h) was half of the rate for the subsoiled treatment (6.6 mm/h), at the end of the 3 h simulation. Rotary subsoiling of newly-planted winter wheat can increase soil moisture stored over-winter and reduce runoff and soil loss on frozen soils, but the benefit of this practice for increasing grain yield has not been proven.
- Authors:
- Roose, E.
- Mededjel, N.
- Arabi, M.
- Mazour, M.
- Morsli, B.
- Source: Soil Erosion and Carbon Dynamics
- Year: 2006
- Summary: Considering the effects of land use change during 1990s in the Tell mountains of northern Algeria, a research programme was developed by the Algerian INRF and the French IRD, to study the influence of land uses and cultural practices on runoff, erosion, soil fertility, and soil organic carbon (SOC) dynamics at the scale of runoff plots (100 to 220 m 2). The study included comparisons between traditional and improved land management systems for the principal soils of northern Algeria. The field experiments were conducted: (i) from 1993 to 1998 in the Beni-Chougran mountains near Mascara, in western Algeria; (ii) from 1991 to 2001 in the Tlemcen mountains in western Algeria; and (iii) from 1988 to 1992 around Medea in central Algeria. These regions are representative of the Tell mountains with regards to landscape, erosion manifestations (sheet erosion, gullies, floods and mass movements), and the various programmes of soil conservation since 1950s. The plots were set up on three soil types: (i) clayey brown Vertic soils on marl (Vertic Haploxeroll in Mascara and Tlemcen, Typic Haploxerert in Medea); (ii) brown calcareous soils on sandstone or limestone (Typic Haploxeroll in Mascara, Tlemcen and Medea); and (iii) red Fersiallitic soils on sandstone (Typic Haploxerept in Tlemcen and Medea). Data showed that at the plot scale, runoff and sheet erosion risks were generally moderate in the semiarid mountains of northern Algeria, even when the fields were cropped on steep slopes. Sediments were richer in OC than the topsoil (0-10 cm depth), and that this enrichment increased with soil surface cover (i.e., bare plots<grazed and cropped plots
- Authors:
- Bolland, M. D. A.
- Brennan, R. F.
- Source: Australian Journal of Experimental Agriculture
- Volume: 46
- Issue: 10
- Year: 2006
- Summary: Zinc (Zn) oxide is the most widely used fertiliser for the predominantly acidic to neutral soils of southwestern Australia. For these soils, the residual value of Zn oxide has been determined for wheat and lupin, but not for barley, oats, canola and triticale, which are also grown in the region. Just after termination of a long-term (17 year) field experiment that measured the residual value of Zn oxide for wheat, soil samples were collected from selected plots to use in 2 glasshouse experiments. The field experiment was on previously unfertilised, newly cleared duplex soil (sand with much lateritic ironstone gravel over clay) and before the experiment started DTPA extractable Zn for the top 10 cm of soil was 17 years for triticale. The 1.0 kg Zn/ha treatment remained fully effective for all crop species. As determined from projected estimates of the data, the time taken for Zn concentrations in young mature growth to reach critical values, the residual value of the 0.5 and 1.0 kg Zn/ ha treatments were least for wheat, barley and oats, were greater for lupin and canola, and greatest for triticale. There were a total of 7 wheat crops and 10 pasture years during the 17 years of the field experiment. For the 0.5 and 1.0 kg Zn/ha treatment applied in the field in 1983, 30 - 34% of the applied Zn was removed in grain of the 7 wheat crops grown before soil samples were collected to do the glasshouse experiments. The pasture was grazed by sheep and it was estimated that 16 - 24% of the Zn applied in 1983 may have been removed in wool and meat. Removal of Zn in grain and animal products therefore decreased the residual value of the Zn oxide fertiliser.
- Authors:
- Kushnak, G. D.
- Riveland, N.
- Eckhoff, J. L.
- Wichman, D. M.
- Carlson, G. R.
- Kephart, K. D.
- Cook, C. R.
- Stougaard, R. N.
- Berg, J. E.
- Nash, D. L.
- Bruckner, P. L.
- Source: Crop Science
- Volume: 46
- Issue: 3
- Year: 2006
- Summary: MT1159CL (Reg. No. CV-992, PI 641221) hard red winter wheat ( Triticum aestivum) was developed by Montana Agricultural Experiment Station and released in September 2004, for its tolerance to imazamox herbicide, adaptation to dryland production in central and south-central Montana, and improved milling and bread baking qualities relative to other available Clearfield winter wheat cultivars. This double-haploid line developed using the wheat * maize hybridization method from the cross FS2/Tiber (PI 517194) has moderate resistance to stripe rust ( Puccinia striiformis f.sp. tritici).
- Authors:
- Barker-Reid, F.
- Gates, W. P.
- Eckard, R. J.
- Wilson, K.
- Baigent, R.
- Galbally, I. E.
- Meyer, C. P.
- Weeks, I. A.
- Source: 4th International Symposium on non-CO2 Greenhouse Gases
- Year: 2005
- Authors:
- Kelly, K.
- Baigent, R.
- Eckard, R.
- Weeks, I.
- Leuning, R.
- Phillips, F.
- Barker-Reid, F.
- Gates, W.
- Grace, P.
- Galbally, I.
- Meyer, M.
- Bentley, S.
- Source: Environmental Sciences
- Volume: 2
- Issue: 2-3
- Year: 2005
- Authors:
- Ding, H.
- Edis, R.
- Zhang, Y.
- Chen, D.
- Li, Y.
- Source: Global Biogeochemical Cycles
- Volume: 19
- Year: 2005
- Authors:
- Source: Soil Use and Management
- Volume: 21
- Issue: 4
- Year: 2005
- Authors:
- Castellanos, J. Z.
- Buenger, E. D.
- Follett, R. F.
- Source: Soil & Tillage Research
- Volume: 83
- Issue: 1
- Year: 2005
- Summary: Conservation tillage could enhance soil organic carbon (SOC) sequestration, but is rarely used in cropping systems in Mexico, especially under irrigation. A study was conducted on a clayey, smectitic, isothermic Udic Pellustert to evaluate the use of traditional-deep and no-tillage systems on SOC dynamics for wheat (Triticum aestivum L.)-corn (Zea mays L.) and wheat-bean (Phaseolus vulgaris L.) cropping systems. Experimental design was a randomized block of five tillage/crop-rotation (two crops per year) systems with four replications: (WC-CTb) wheat-corn, burning the residues of both crops, plowing and disking twice (WC-CT) wheat-corn under conventional tillage (plowing and disking twice to incorporate crop residues following the harvest of each crop), (WC-NT) wheat-corn under no-till, (WB-CT) wheat-bean under conventional tillage, and (WB-NT) wheat-bean under no-till. Each crop in the sequence received one of three fertilizer-N rates broadcast as urea: (a) 0, 150, and 300 kg N ha(-1) for corn; (b) 0, 40, and 80 kg N ha(-1) for bean; and (c) 0, 125, and 250 kg N ha(-1) for wheat. The baseline year was 1994, and relative changes were measured from 1994 to 1999 for grain yield and residue production, crop residue C and delta(13)C, SOC, soil C/N ratio, and change in soil delta(13)C. Interaction of cropping system x fertilizer-N rate was highly important to grain yield and crop residue production and amount of crop-residue C produced. High N rates increased SOC sequestration and decreased soil C/N ratios. In WC systems, more negative delta(13)C was associated with higher N rates, indicating increased contribution of wheat (a C(3) plant) residue C relative to corn (a C(4) plant). In WB, N-rate and tillage had no effect on SOC sequestration. Highest rate of SOC sequestration was under WC-NT and when increases in SOC from 1994 to 1999 were annualized was 1.0 and 1.9 Mg SOC yr(-1) in the 0-15- and 15-30-cm depths, respectively. Corresponding SOC in 0-15- and 15-30-cm depths in the WC-CT treatment was 0.2 and 0.6 Mg yr(-1) and amounts in all other treatments were equal or lower than those observed for WC-CT. There was a significant correlation between aboveground crop-residue C produced and amount of SOC sequestered. Results from this study indicate no-till on N-fertilized WC systems can potentially increase SOC sequestration on large areas of irrigated Vertisols in Central Mexico while maintaining high crop yields.
