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D G Christian - One of the best experts on this subject based on the ideXlab platform.
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interactions of straw disposal methods and Direct Drilling or cultivations on winter wheat triticum aestivum grown on a clay soil
Journal of Agricultural Engineering Research, 1999Co-Authors: D G Christian, E T G Bacon, D Brockie, D M Glen, R J Gutteridge, J F JenkynAbstract:A field experiment was started in 1979 on a clay soil to compare effects of baling to leave stubble only, chopping and spreading straw or burning on the yield of winter wheat (Triticum aestivum). Results are reported for the period 1982–1988 with occasional references to earlier years. The crop was either Direct drilled or sown after incorporation of straw or ash by cultivation to depths of 5, 15 or 25 cm. Tine cultivation was used until 1983 then replaced by ploughing. Averaged over a nine-year period, Direct Drilling into chopped straw caused a one-third reduction in yield compared to Direct Drilling where the straw was burnt. Over the same period, 5 cm deep straw incorporation resulted in one-fifth less yield compared to crops after burning. From 1985 to 1988, ploughing to 15 or 25 cm resulted in respectively 1 and 9% less yield if straw was incorporated rather than burnt. There was no evidence that these reductions were a consequence of consistent differences in pests or diseases. Temporary (1 year) burning after seven years of incorporating chopped straw increased average yield on tillage treatments by 17%. On this soil, ploughing at least to 15 cm is recommended to improve reliability of crop establishment. The average yields obtained from the straw returned treatments indicates that it was the presence of straw rather than the amount that most influenced yield.
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losses of nitrate nitrogen in water draining from under autumn sown crops established by Direct Drilling or mouldboard ploughing
European Journal of Soil Science, 1993Co-Authors: M J Goss, D G Christian, K. R. Howse, P W Lane, G L HarrisAbstract:SUMMARY The leaching of nitrate-N under autumn-sown arable crops was measured using hydro-logically isolated plots, about 0.24 ha in area, from 1984–1988. Fluxes of water and nitrate moving over the soil surface (surface runoff), at the interface between topsoil and subsoil (interflow), and in the subsoil (drainflow) were monitored in plots with mole-and-pipe drain systems (drained plots); surface runoff and interflow only were monitored in ‘undrained’ plots. Half the drained and undrained plots were Direct-drilled, and on the other half seedbeds were prepared by tillage to 200 mm. Tillage increased the total leaching loss of nitrate by 21 % compared with Direct Drilling in drained plots. About 95% or the nitrate moving from the soil was present in the water intercepted by the subsoil drains in these plots. In undrained plots less water and nitrate were collected in total; more of the nitrate was present in interflow on ploughed plots and in surface runoff in Direct-drilled land. Losses of nitrate for the whole experiment from 1978-1988 were analysed. This showed that, between the harvest of one crop and the spring application of fertilizer to the next, loss of nitrate-N from ploughed land (Lp) was approximated by Lp=22+Fkg N ha−1, where F was the autumn fertilizer-N applied. After fertilizer was applied in spring, loss of nitrate-N depended on rainfall such that for 100 mm rainfall about 30% of the fertilizer-N was lost by leaching. About 18% more nitrate-N was lost from Direct-drilled land than from ploughed land in spring, but the total loss was generally small compared to that over winter. The apparent net mineralization of organic-N was measured in 1988. In autumn and winter there was little effect of tillage treatment (26 and 31 kg N ha−1 on Direct drilled and tilled plots respectively). However, over the year 83 kg N ha−1 were mineralized in tilled plots, and 67 kg N ha−1 in Direct-drilled plots. Five factors governing the leaching of nitrate are assessed and this identified that fertilizer nitrogen application to the seedbed of winter sown crops and the mineralization of nitrogen from the residues of the previous crop are the most significant factors for nitrogen leaching in the UK.
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a long term comparison of ploughing tine cultivation and Direct Drilling on the growth and yield of winter cereals and oilseed rape on clayey and silty soils
Soil & Tillage Research, 1990Co-Authors: D G Christian, E T G BaconAbstract:Abstract The effects of mouldboard ploughing, shallow tined cultivation and Direct Drilling on yields of winter wheat, barley, oats and oilseed rape were compared over 10 years. Three field experiments were conducted on two non-calcareous clays (stagnogleys) and a weakly structured silty soil (argillic brown earth). Two spring N levels were applied to the winter wheat plots on the clay soil in three years and to the winter barley plots on the silty soil in one year. This paper reports the soil bulk density and water content at sowing and the crop growth, yield components and yields obtained during the later years of the study: 1979–1984 on the clayey soils and 1981–1984 on the silty soil. In the years when cereals were grown, differences in yield between cultivation treatments were small and inconsistent. Oilseed rape yielded significantly more after Direct Drilling than ploughing because of better establishment and uniformity of growth. The success of continuous reduced tillage depended on both burning crop residues and good weed control.
E T G Bacon - One of the best experts on this subject based on the ideXlab platform.
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interactions of straw disposal methods and Direct Drilling or cultivations on winter wheat triticum aestivum grown on a clay soil
Journal of Agricultural Engineering Research, 1999Co-Authors: D G Christian, E T G Bacon, D Brockie, D M Glen, R J Gutteridge, J F JenkynAbstract:A field experiment was started in 1979 on a clay soil to compare effects of baling to leave stubble only, chopping and spreading straw or burning on the yield of winter wheat (Triticum aestivum). Results are reported for the period 1982–1988 with occasional references to earlier years. The crop was either Direct drilled or sown after incorporation of straw or ash by cultivation to depths of 5, 15 or 25 cm. Tine cultivation was used until 1983 then replaced by ploughing. Averaged over a nine-year period, Direct Drilling into chopped straw caused a one-third reduction in yield compared to Direct Drilling where the straw was burnt. Over the same period, 5 cm deep straw incorporation resulted in one-fifth less yield compared to crops after burning. From 1985 to 1988, ploughing to 15 or 25 cm resulted in respectively 1 and 9% less yield if straw was incorporated rather than burnt. There was no evidence that these reductions were a consequence of consistent differences in pests or diseases. Temporary (1 year) burning after seven years of incorporating chopped straw increased average yield on tillage treatments by 17%. On this soil, ploughing at least to 15 cm is recommended to improve reliability of crop establishment. The average yields obtained from the straw returned treatments indicates that it was the presence of straw rather than the amount that most influenced yield.
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a long term comparison of ploughing tine cultivation and Direct Drilling on the growth and yield of winter cereals and oilseed rape on clayey and silty soils
Soil & Tillage Research, 1990Co-Authors: D G Christian, E T G BaconAbstract:Abstract The effects of mouldboard ploughing, shallow tined cultivation and Direct Drilling on yields of winter wheat, barley, oats and oilseed rape were compared over 10 years. Three field experiments were conducted on two non-calcareous clays (stagnogleys) and a weakly structured silty soil (argillic brown earth). Two spring N levels were applied to the winter wheat plots on the clay soil in three years and to the winter barley plots on the silty soil in one year. This paper reports the soil bulk density and water content at sowing and the crop growth, yield components and yields obtained during the later years of the study: 1979–1984 on the clayey soils and 1981–1984 on the silty soil. In the years when cereals were grown, differences in yield between cultivation treatments were small and inconsistent. Oilseed rape yielded significantly more after Direct Drilling than ploughing because of better establishment and uniformity of growth. The success of continuous reduced tillage depended on both burning crop residues and good weed control.
A. G. Hopkins - One of the best experts on this subject based on the ideXlab platform.
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Plant development, and N and P use of winter barley
Plant and Soil, 1991Co-Authors: A. G. HopkinsAbstract:Winter barley ( Hordeum vulgare L. cv. ‘Kamiak’) was grown at three landscape positions of a representative toposequence in the Palouse region of eastern Washington. This region is typified by rolling topography marked by severe erosion of steep slope positions that has altered soil productivity in the landscape. The objectives of this research were to identify soil factors which limit plant development and nutrient use efficiency in the eroded slope positions, and to suggest potential management practices for overcoming these limitations. Direct Drilling into cereal stubble resulted in retardation of early plant development of winter barley. Lower N and P accumulation by early tillering under no-till conditions were related these effects on dry matter. These reductions were generally overcome by anthesis. Comparison of tillage systems demonstrated that Direct Drilling into crop residues increased yields by 16% over conventional tillage at an eroded ridgetop position of one of the two toposequences examined. Benefits derived in the no-till system under the high N rates occurred during grainfilling, as indicated by greater numbers of heads and higher kernel weights at final harvest. Tillage system had no effect on grain production at other landscape positions that featured higher overall yields under either tillage system. Short-term benefits of no-till systems may be most evident at slope positions where water use is most limited.
Y Duval - One of the best experts on this subject based on the ideXlab platform.
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Direct Drilling of sugar beet beta vulgaris l into a cover crop effects on soil physical conditions and crop establishment
Soil & Tillage Research, 1995Co-Authors: Guy Richard, J Boiffin, Y DuvalAbstract:Abstract Direct Drilling of sugar beet ( Beta vulgaris L.) into an autumn sown cover crop may reduce field work in spring and environmental damage, such as soil erosion and nitrate leaching, but the balance of its negative and positive effects on crop establishment is unknown. This study compared the effects of Drilling sugar beet Directly into a cover crop of wheat ( Triticum aestivum L.) or rye ( Secale cereal L.), or after conventional tillage in spring, on soil physical conditions and crop establishment. The experiments were conducted over 4 years in the north of France on three soil types: chalky soil (rendzina), loam soil (calcic cambisol) and silt loam soil (gleyic luvisol). Direct Drilling caused less soil compaction than conventional Drilling; the wheel tracks for seed bed preparation were made in drier conditions for Direct Drilling because of the change in tillage time (autumn for Direct Drilling vs. spring for conventional Drilling). Seed bed structure, temperature and water content, and seed placement were very similar for the two Drilling techniques (except in the silt loam soil) because of soil tillage done by the sugar beet seed drill and removal of cover crop residues over the sugar beet rows. Final emergence percentage was lower with Direct Drilling because of predator damage (by skylarks ( Alauda arvensis ) and/or field mice ( Apodemus sylvaticus ). Seedling growth after emergence was slower with Direct Drilling. The negative effects of Direct Drilling on sugar beet establishment may be counteracted by increasing the seed density, or by its positive effects on soil structure and consequently the possibility to sow sugar beet earlier. Because of its environmental advantages, Direct Drilling of sugar beet into a cover crop is an interesting technique for large farms with heavy work loads in spring in areas where the soil has a high aggregate stability.
Bernward Marlander - One of the best experts on this subject based on the ideXlab platform.
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yield decrease in sugar beet caused by reduced tillage and Direct Drilling
European Journal of Agronomy, 2009Co-Authors: Heinzjosef Koch, Jan Dieckmann, Andreas Buchse, Bernward MarlanderAbstract:Abstract In a long-term series of on-farm tillage trials (10 loessial sites in southern and eastern Germany; annual mouldboard ploughing 0.25–0.3 m deep, mulching with a rigid-tine cultivator 0.1–0.15 m deep, Direct Drilling with no tillage except seedbed preparation for sugar beet solely) sugar beet yield was significantly decreased by Direct Drilling compared to ploughing. This study was conducted to (i) show that the lower plant density caused by mulching and Direct Drilling contributes to yield decrease but explains effects just partially, and (ii) determine the relation between soil structural properties and sugar beet yield. In 2003–2005 plant density experiments (53,000, 65,000 and 82,000 plants ha −1 ) were introduced to tillage plots on five selected environments. Yield and soil structural properties of four layers representing 0–0.43 m soil depth were determined. White sugar yield (WSY) significantly declined with Direct Drilling compared to ploughing treatment, whereas mulching treatment diminished WSY less pronounced. Moreover, decreasing plant density significantly lowered WSY. No interactions between tillage and plant density occurred, revealing that both factors additively affected WSY. Decreasing tillage depth increased penetration resistance (PR) and dry bulk density (DBD), and diminished air filled pore volume (AFPV) in the topsoil down to 0.27 m depth. Several soil structural parameters were closely correlated with each other as well as WSY. Variation of single parameters explained up to 60% of WSY variance attributed to tillage. Combining DBD from 0.03 to 0.07 m depth, average PR from 0.03 to 0.27 m and AFPV from 0.03 to 0.18 m soil depth explained 77% of the tillage effect. Nevertheless, multi-collinearity of soil physical parameters allowed no clear conclusions on the cause-and-effect mechanisms. Conclusively, lowered plant density and soil structure degradation due to reduced tillage may independently decrease sugar beet yield. When grown on loessial soils this crop requires mechanical loosening down to 0.15–0.20 m depth to produce high yields.