• Authors:
    • Pauletti, V.
    • Piva, J.
    • Santos, N.
    • Dieckow, J.
    • Bayer, C.
    • Molin, R.
    • Favaretto, N.
  • Source: Soil & Tillage Research
  • Volume: 111
  • Issue: 2
  • Year: 2011
  • Summary: To improve C sequestration in no-till soils requires further development of crop rotations with high phytomass-C additions. The objectives of this study were (i) to assess long-term (17 years) contributions of cover crop- or forage-based no-till rotations and their related shoot and root additions to the accumulation of C in bulk and in physical fractions of a subtropical Ferralsol (20-cm depth); and (ii) infer if these rotations promote C sequestration and reach an eventual C saturation level in the soil. A wheat ( Triticum aestivum L., winter crop)-soybean ( Glycine max (L.) Merr, summer crop) succession was the baseline system. The soil under alfalfa ( Medicago sativa L., hay forage) intercropped every three years with maize ( Zea mays L., summer crop) had the highest C accumulation (0.44 Mg C ha -1 year -1). The bi-annual rotation of ryegrass ( Lolium multiflorum Lam., hay winter forage)-maize-ryegrass-soybean had a soil C sequestration of 0.32 Mg C ha -1 year -1. Among the two bi-annual cover crop-based rotations, the vetch ( Vicia villosa Roth, winter cover crop)-maize-wheat-soybean rotation added 7.58 Mg C ha -1 year -1 as shoot plus root and sequestered 0.28 Mg C ha -1 year -1. The counterpart grass-based rotation of oat ( Avena strigosa Schreb., winter cover crop)-maize-wheat-soybean sequestered only 0.16 Mg C ha -1 year -1, although adding 13% more C (8.56 Mg ha -1 year -1). The vetch legume-based rotation, with a relative conversion factor (RCF) of 0.147, was more efficient in converting biomass C into sequestered soil C than oat grass-based rotation (RCF=0.057). Soil C stocks showed a close relationship ( R2=0.72-0.98, P<0.10) with root C addition, a poor relationship with total C addition and no relationship with shoot C addition. This suggests a more effective role of root than shoot additions in C accumulation in this no-till soil. Most of the C accumulation took place in the mineral-associated organic matter (71-95%, in the 0-5 cm layer) compared to the particulate organic matter. The asymptotic relationship between root C addition and C stocks in bulk soil and in mineral-associated fraction supports the idea of C saturation. In conclusion, forages or legume cover crops contribute to C sequestration in no-till tropical Ferrasols, and most of this contribution is from roots and stored in the mineral-associated fraction. This combination of soil and rotations can reach an eventual soil C saturation.
  • Authors:
    • Sarker, S. C.
    • Patra, P. S.
    • Mula, G.
    • Paramanik, B.
  • Source: Journal of Crop and Weed
  • Volume: 7
  • Issue: 1
  • Year: 2011
  • Summary: Zero tillage saves tillage and irrigation costs, results in yield gains through a possible improvement in sowing time and enhanced fertilizer and water use efficiencies. The present study was conducted to explore the possibilities of saving critical inputs and to enhance the profit margin of the rural farmers of Uttar Dinajpur, Dakshin Dinajpur, Malda and Murshidabad districts of West Bengal through National Agricultural Innovation Project. Mean grain yield of 10 villages showed that zero tillage practices produced 8.004% more grain yield than conventional tillage method. On an average zero tillage method save total cost of Rs. 4449.67 ha -1 and increase profit margin of Rs. 7056.25 ha -1. Zero till field also recorded higher B:C ratio of 0.923 as compared to conventional tillage method (0.432).
  • Authors:
    • Scherer, E. E.
  • Source: Agropecuaria Catarinense
  • Volume: 24
  • Issue: 2
  • Year: 2011
  • Summary: Organic agriculture in no-till system requires a new set of producer skills especially in the area of soil fertility and fertilizer use. In a field experiment in organic system in Chapeco, SC, Southern Brazil, the effect of different organic fertilizers (poultry dry litter, swine deep litter, swine composted manure, cattle composted manure and liquid swine manure) on the corn and common been yields was investigated. The organic fertilizers were scattered on the soil surface in the no-till system on the day of the sowing of common bean and corn. The solid manure was applied at 5 and 10 t/ha, dry weight, and the liquid manure at 30 and 60 m 3/ha for common beans and corn, respectively. A completely randomized block experimental design with six replications was used. The utilization of solid and liquid organic manure increased the grain yield of both cultures in all six years. Common beans and corn grain average yield with organic fertilizers use was 30% and 54% greater than yield without fertilizer, respectively. Solid swine manure and organic compost had a better performance on common bean grain yield, and liquid swine manure on corn yield.
  • Authors:
    • Schindler, U.
    • Muller, L.
  • Source: AMA-Agricultural Mechanization in Asia, Africa and Latin America
  • Volume: 42
  • Issue: 4
  • Year: 2011
  • Summary: Efficient water use and intelligent water management are essential for sustainable agricultural production. Long-term soil hydrological measurements were used to quantify deep drainage rates and nitrate losses from arable land managed under various farming regimes (integrated, integrated with irrigation, ecologic and low input) and tillage systems (plough and no till) in the Pleistocene region of Northeast Germany from 1994 to 2007. As dependent on the management system, the nitrate concentration varied between 40 and 150 mg l -1. In connection with annual deep drainage rates between 100 mm and 200 mm during the study period, the annual nitrogen loss varied between 14 and 41 kg ha -1. Differences in nitrogen loss observed between the farming systems were low, but yields increased and nitrogen losses decreased as a result of irrigation throughout the variants. No-till treatment resulted in reduced nitrate leaching (18 kg ha -1) as compared with the tillage systems with plough and tooth cultivator (27 kg ha -1).
  • Authors:
    • Jones, B. P.
    • Sequeira, C. H.
    • Alley, M. M.
  • Source: Soil Biology and Biochemistry
  • Volume: 43
  • Issue: 2
  • Year: 2011
  • Summary: Particulate organic matter (POM) and light fraction (LF) organic matter are potentially labile (active) fractions of soil organic matter (SOM) that have been shown to be indicators of short-term changes in soil management practices (e.g. tillage, manure and fertilizer applications, and crop rotation). These two fractions consist mainly of partially decomposed plant residues, microbial residues, seeds, and spores forming organo-mineral complexes with soil mineral particles; however, they cannot be used as synonyms because of their different chemical composition and structure. Particulate-OM is recovered by size-based procedures while LF is generally recovered in two distinct fractions [free-LF (FLF) and occluded-LF (OLF)] using density-based solutions in conjunction with soil-aggregate disruption. Solutions used in these density-based separations have most commonly varied in density from 1.6 to 2.0 g cm -3. Sodium iodide (NaI) and sodium polytungstate (SPT) are the chemicals most often used to prepare the density solutions in LF recovery but comparisons of the effectiveness of two solutions have not been conducted. The objectives of this research were: (1) compare the efficiency of similar density solutions of NaI and SPT in recovering FLF; and (2) compare POM, FLF, and OLF as possible sensitive indices of short-term soil changes due to tillage management. Soil samples were collected at 0-15 cm depth from a cropping system experiment conducted on a silt loam Ultisol. Plots selected for sampling had received either reduced till (RT) or no-till (NT), and cropping was continuous corn silage for a period of 3 years prior to sampling. Solutions of NaI and SPT at densities of 1.6 and 1.8 g cm -3 were used to recover FLF, and OLF was recovered with SPT solution at a density of 2.0 g cm -3 from the soil pellet remaining after FLF recovery with SPT 1.6 g cm -3. The average total soil organic carbon (SOC) content of these samples was of 12.7 g kg -1, and carbon-POM (C-POM), carbon-FLF (C-FLF), and carbon-OLF (C-OLF) represented 22.4, 5.5, and 5.2% of it, respectively. In general, C-FLF and nitrogen-FLF (N-FLF) contents recovered did not differ significantly between chemical solutions (NaI or SPT) adjusted to the same density (1.6 or 1.8 g cm -3). Increasing the density within a specific solution (NaI or SPT) resulted in significantly higher C-FLF and N-FLF recovery. For instance, C-FLF recovery averaged 637 and 954 mg kg -1 at 1.6 and 1.8 g cm -3, respectively. For both chemicals increasing density from 1.6 to 1.8 g cm -3 reduced the variability in recovering C-FLF and N-FLF with coefficient of variation values decreasing from a range of 14.9-19.1% for densities of 1.6 g cm -3 to 6.7-10.4% when densities increased to 1.8 g cm -3. In the present work, POM and OLF were more sensitive than FLF to changes in tillage management, with significantly greater amounts of the sensitive fractions in RT samples. A better sensitivity of FLF would be expected if treatments dealing with residue input (e.g. crop rotation and cover crop) were evaluated.
  • Authors:
    • Sequeira, C. H.
    • Alley, M. M.
  • Source: Soil Science Society of America Journal
  • Volume: 75
  • Issue: 5
  • Year: 2011
  • Summary: Soil organic matter (SOM) is commonly used as an indicator of soil quality, with different fractions being used as indices to measure changes in SOM caused by management. The objective of this study was to compare whether selected SOM fractions exhibited sensitivity to short-term changes in management. The experiment was conducted for similar to 3 yr as a split-split-plot design with crop rotation as the whole-plot treatment factor, tillage as the subplot treatment factor, and cover crop management as the sub-subplot treatment factor. Soil samples were collected at the 0- to 15-cm depth. Soil organic C (SOC) and N, particulate organic matter (POM), free light fraction (FLF), Illinois soil N test (ISNT), and easily oxidizable C (EOC) were tested as possible sensitive indices to changes in management. The stable fraction SOC was only affected by cover crop management, while C and N contents and C/N ratio of the labile POM and FLF fractions were affected by additional management practices. Between POM and FLF, the latter was the most sensitive, with cover crop management having the greatest effect. Because FLF is chemically and structurally closer to plant residues than POM, the sensitivity rank position of these fractions would probably be at least more similar if only tillage management was considered. In addition, the lack of sensitivity of ISNT and EOC to any tested management practice is added to previous studies that have raised questions of the representation of the labile SOM pool through these fractions.
  • Authors:
    • Shipitalo, M. J.
    • Owens, L. B.
  • Source: Journal of Environmental Quality
  • Volume: 40
  • Issue: 4
  • Year: 2011
  • Summary: Residual herbicides regularly used in conjunction with conservation tillage to produce corn ( Zea mays L.) and soybean [ Glycine max (L.) Merr] are often detected in surface water at concentrations that exceed their U.S. maximum contaminant levels (MCL) and ecological standards. These risks might be reduced by planting glyphosate-tolerant varieties of these crops and totally or partially replacing the residual herbicides alachlor, atrazine, linuron, and metribuzin with glyphosate, a contact herbicide that has a short half-life and is strongly sorbed to soil. Therefore, we applied both herbicide types at typical rates and times to two chisel-plowed and two no-till watersheds in a 2-yr corn/soybean rotation and at half rates to three disked watersheds in a 3-yr corn/soybean/wheat-red clover ( Triticum aestivum L.- Trifolium pratense L.) rotation and monitored herbicide losses in surface runoff for three crop years. Average dissolved glyphosate loss for all tillage practices, as a percentage of the amount applied, was significantly less ( P≤0.05) than the losses of atrazine (21.4*), alachlor (3.5*), and linuron (8.7*) in corn-crop years. Annual, flow-weighted, concentration of atrazine was as high as 41.3 g L -1, much greater than its 3 g L -1 MCL. Likewise, annual, flow-weighted alachlor concentration (MCL=2 g L -1) was as high as 11.2 and 4.9 g L -1 in corn- and soybean-crop years, respectively. In only one runoff event during the 18 watershed-years it was applied did glyphosate concentration exceed its 700 g L -1 MCL and the highest, annual, flow-weighted concentration was 3.9 g L -1. Planting glyphosate-tolerant corn and soybean and using glyphosate in lieu of some residual herbicides should reduce the impact of the production of these crops on surface water quality.
  • Authors:
    • Shrivastava, A. K.
    • Satyendra, J
  • Source: Agricultural Engineering International
  • Volume: 13
  • Issue: 2
  • Year: 2011
  • Summary: A tractor drawn (TD) till plant machine was designed and developed with the help of computer aided design package for adoption of minimum till technology by the farmers, in black cotton soil conditions. This machine was evaluated and compared with the performance of a zero till drill and conventional practices at Jawaharlal Nehru Agricultural University farms as well as at a farmer's fields. It was found that the total time and cost required for tillage and sowing operations by till plant machine was 5.09 h/ha and Rs. 410.37/ha, which is 72.23 per cent less time required than conventional practices of wheat cultivation but is 28.83 per cent more time required than zero till drill practices. The average yield by tractor till plant machine was 26.96 q/ha, whereas, by conventional practices and tractor drawn zero till drill was 25.91 and 22.72 q/ha. respectively. The soil conditions were also found better in the case of the T.D. till plant machine.
  • Authors:
    • Mahapatra, B. S.
    • Saini, S. K.
    • Shweta
    • Singh, R. K.
  • Source: Indian Journal of Agricultural Sciences
  • Volume: 81
  • Issue: 2
  • Year: 2011
  • Summary: To ameliorate the ill effects of traditional rice-wheat cropping system efforts have been made to develop several resource conservation technologies. Conventional method of wheat sowing requires intensive pre-planting cultivation, which are labour, time and energy intensive. The field experiment was conducted at Govind Ballabh Pant University of Agriculture and Technology, Pantnagar during rainy season of 2005-06 to winter season of 2006-07. Maximum mean grain (4 237 kg/ha) and straw (6 235 kg/ha) yields of wheat were obtained from direct-seeded rice plots. Nutrient uptake (NPK) by the wheat crop was highest under direct-seeded rice due to rice establishment methods. Maximum mean grain (4 535 kg/ha) and straw (6 423 kg/ha) yields were obtained under zero till. The mean wheat grains/spike under zero till drill wheat was 0.79, 6.93 and 4.09% more than that of strip till drill, bed planted and conventional wheat, respectively. Zero till drill wheat exhibited significantly higher nutrient uptake than that of conventional, bed planted and strip till drill wheat.
  • Authors:
    • Silveira, F. de M.
    • Silva, E. D. B. da
    • Pauletti, V.
    • Favaretto, N.
    • Vezzani, F. M.
    • Dieckow, J.
  • Source: Revista Brasileira de Ciencia do Solo
  • Volume: 35
  • Issue: 5
  • Year: 2011
  • Summary: The use of manure in agricultural system is a possibility to dispose of the waste generated in animal production, but improper use can cause environmental problems. The general objective of this study was to evaluate carbon and nitrogen concentrations and losses in runoff in four doses of liquid dairy manure (0, 60, 120, 180 m 3 ha -1 yr -1) applied to a silt clay loam Oxisol with 13% slope, in no-till with soybean, oat, corn, and wheat in crop rotation. The runoff was collected for two years and seven months in 60 L containers after every rain with runoff from at least one plot. Soluble nutrients were analyzed in runoff samples filtered through a 0.45 m membrane and total nutrients in unfiltered samples. The application of liquid dairy manure reduced the losses of organic carbon and nitrogen, with positive consequences for water quality. However, higher rates tended to increase the concentrations of these elements and, consequently, reduce water quality. The weighted average concentrations of nitrate were below the limit allowed by Brazilian legislation, but ammonium exceeded the threshold values, indicating the need of control measures to prevent the runoff from reaching the water bodies, even in no-tillage systems. It should be pointed out that these data were obtained under low potential polluting conditions, i.e, on 13% slope, low rainfall and with a minimum interval of ten days between manure application and rainfall. Further studies should also evaluate nitrate leaching.