• Authors:
    • Jorge, R. F.
    • Cora, J. E.
    • Martins, M. dos R.
    • Marcelo, A. V.
  • Source: Soil & Tillage Research
  • Volume: 104
  • Issue: 1
  • Year: 2009
  • Summary: The adaptation of no-tillage system in tropical regions depends on the suitable choice of summer and winter crops which should contribute to improvement of soil properties. The aim of the present study was to determine the effect of crop sequences on soil aggregation and contents of organic C and polysaccharides in aggregates of a Rhodic Eutrudox under no-tillage. The treatments consisted of the combination of four summer crop sequences and seven winter crop sequences. The summer crop sequences were: maize monocrop ( Zea mays L.) (MM); soybean monocrop ( Glycine max (L.) Merrill) (SS); crop sequence of soybean/maize/soybean/maize (SM); crop sequence of rice ( Oryza sativa L.)/bean ( Phaseolus vulgaris L.)/cotton ( Gossypium hirsutum L.)/bean (RB). The winter crops were: maize, sunflower ( Helianthus annuus L.), radish ( Raphanus sativus L.), pearl millet ( Pennisetum americanum (L.) Leeke), pigeon pea ( Cajanus cajan (L.) Millsp), grain sorghum ( Sorghum bicolor (L.) Moench) and sunn hemp ( Crotalaria juncea L.). The highest total organic C, total polysaccharides and dilute acid-extracted polysaccharides contents were found in 2.00-1.00 mm water-stable aggregates and the lowest contents were found in
  • Authors:
    • Raper, R. L.
    • Reddy, K. C.
    • Nyakatawa, E. Z.
    • Reddy, S. S.
    • Reeves, D. W.
    • Lemunyon, J. L.
  • Source: Field Crops Research
  • Volume: 114
  • Issue: 2
  • Year: 2009
  • Summary: Long-term field experiments are needed to fully realize positive and negative impacts of conservation tillage and poultry litter application. A study was initiated on a Decatur silt loam soil at the Tennessee Valley Research and Extension Center, Belle Mina, AL, USA in 1996 to evaluate cotton (Gossypium hirsutum L.) performance with long-term poultry litter (PL) application under different tillages and to Study the build up of phosphorus (P) With application of PL. Treatments include incomplete factorial combinations of three tillage systems [conventional till (CT), mulch till (MT), and no-till (NT)], two cropping systems [cotton-fallow and cotton-winter rye (Secale cereale L.)], and two nitrogen sources and rates [100 kg N ha(-1) from ammonium nitrate (AN), and 100 and 200 kg N ha(-1) from poultry litter (PL)]. Cotton was rotated with corn (Zea mays L.) every third year. Results from 2003 to 2008 showed that all tillages gave similar cotton lint yields with AN at 100 kg N ha(-1). Application of PL at 100 kg N ha(-1) in NT plots resulted in 12 and 11% yield reductions compared to that of CT and MT, respectively. However, NT plots with higher quantity of PL (200 kg N ha(-1)) gave similar yields to CT and MT at 100 kg N ha(-1). During corn years, higher residual fertility of PL, in terms of grain yields, was observed in NT plots compared to CT and MT. Long-term PL application (100 kg N ha(-1) year(-1)) helped to maintain original soil pH in CT and MT while AN application decreased soil pH. In NT plots, PL at 100 kg N ha(-1) was not sufficient to maintain original soil pH, but 200 kg N ha(-1) maintained original pH. Although not-significant, elevated P levels were observed in all tillages compared to original P levels which indicates possibility of P build up in future with further application of PL. Application of PL at double rate (200 kg N ha(-1)) in NT plots resulted in significant build up of P. Results indicate that NT gives similar yields to CT when received AN. but needs higher rate of PL application to achieve similar yields to CT. (C) 2009 Elsevier B,V. All rights reserved.
  • Authors:
    • Salado-Navarro, L. R.
    • Sinclair, T. R.
  • Source: Agricultural Systems
  • Volume: 102
  • Issue: 1/3
  • Year: 2009
  • Summary: Cropping schemes have developed in east-central Argentina for rainfed soybean (Glycine max Merr.) production that invariably employ no-tillage management. Often these schemes include growing soybean in a sequence of crops including wheat ( Triticum aestivum L.) and maize ( Zea mays L.). The full impact of various rotation schemes on soil water balance through a sequence of seasons has not been explored, although the value of these rotations has been studied experimentally. The objective of this work was to investigate through simulations, potential differences in temporal soil water status among rotations over five years. In this study, mechanistic models of soybean (Soy), maize (Maz), and wheat (Wht) were linked over a five-years period at Marcos Juarez, Argentina to simulate soil water status, crop growth, and yield of four no-till rotations (Soy/Soy, Soy/Wht, Soy/Maz, and Soy/Maz/Wht). Published data on sowing dates and initial soil water contents in the first year from a no-till rotation experiment were used as inputs to the model. After the first year, soil water status output from the model was used to initiate the next crop simulation in the sequence. The results of these simulations indicated a positive impact on soil water balance resulting from crop residue on the soil surface under no-till management. Continuous soybean and the two-year soybean/maize rotation did not efficiently use the available water from rainfall. Residue from maize was simulated to be especially effective in suppressing soil evaporation. Thus, the Soy/Maz simulation results indicated that this rotation resulted in enhanced soil water retention, increased deep water percolation, and increased soybean yields compared with continuous soybean crops. The simulated results matched well with experimental observations. The three-crop rotation of Soy/Maz/Wht did not increase simulated soybean yields, but the additional water retained as a result of decreased soil evaporation resulting from the maize residue allowed the addition of a wheat crop in this two-year rotation. Simulated soybean yields were poorly correlated with both the amount of soil water at sowing and the rainfall during the cropping period. These results highlight the importance of temporal distribution of rainfall on final yield. These models proved a valuable tool for assessing the consequences of various rotation schemes now being employed in Argentina on temporal soil water status, and ultimately crop yield.
  • Authors:
    • Sandor, M.
    • Domuta, C.
    • Samuel, A. D.
    • Vuscan, A.
  • Source: Research Journal of Agricultural Science
  • Volume: 41
  • Issue: 2
  • Year: 2009
  • Summary: Agricultural practices that reduce soil degradation and improve agricultural sustainability are needed particularly for preluvosoil. No-tillage planting causes minimal soil disturbance and combined with crop rotation may hold potential to meet these goals. Soil enzyme activities can provide information on how soil management affects the soil potential to perform processes, such as decomposition and nutrient cycling. Soil enzyme activities (actual and potential dehydrogenase, catalase, acid and alkaline phosphatase) were determined in the 0-20-, 20-40- and 40-60-cm layers of a preluvosoil submitted to a complex tillage (no-till and conventional tillage) and crop rotation (2- and 6-crop rotations) experiment. Each activity in both non-tilled and conventionally tilled soil under all crops of both rotations decreased with increasing sampling depth. No-till - in comparison with conventional tillage - resulted in significantly higher soil enzymatic activities in the 0-20- and in significantly lower activities in the deeper layers. The soil under maize or wheat was more enzyme-active in the 6- than in the 2-crop rotation. In the 2-crop rotation, higher enzymatic activities were recorded under wheat than under maize. The enzymatic indicators of soil quality were calculated from the values of enzymatic activities determined in the plots of the 6-crop rotation. The results obtained show that the different hierarchies of the six plots as registered in 2008 may be related to the different nature of crops and kind of fertilisers. This means that by determination of enzymatic activities, valuable information can be obtained regarding fertility status of soils.
  • Authors:
    • Fontaneli, R. S.
    • Santos, H. P. dos
    • Spera, S. T.
    • Tomm, G. O.
  • Source: Revista Brasileira de Ciência do Solo
  • Volume: 33
  • Issue: 1
  • Year: 2009
  • Summary: Soil physical characteristics were evaluated of a typical dystrophic Red Latosol (Typic Haplorthox) located in Passo Fundo, State of Rio Grande do Sul, Brazil, after ten years (1993 to 2003) under mixed production systems. The effects of production systems integrating grain production with winter annual and perennial forages under no-tillage were assessed. Five mixed cropping systems were evaluated: (i) wheat/soyabean, white oat/soyabean, and common vetch ( Vicia sativa)/maize; (ii) wheat/soyabean, white oat/soyabean, and annual forages (black oat ( Avena nuda) + common vetch)/maize; (iii) perennial cool season forages (fescue ( Festuca) + white clover ( Trifolium repens) + red clover ( T. pratense) + birdsfoot trefoil ( Lotus corniculatus)); and (iv) perennial warm season forages (bahiagrass ( Paspalum notatum) + black oat + ryegrass ( L. perenne) + white clover + red clover + birdsfoot trefoil). System V lucerne as hay crop was established in an adjacent area in 1994. Half of the areas under the systems III, IV, and V returned to system I after the summer of 1996 (southern hemisphere). The crops, both summer and winter, were grown under no-till. The treatments were arranged in a randomized complete block design, with four replications. Soil core samples were also collected in a subtropical forest fragment adjacent to the experimental area. The variations in soil bulk density, total porosity, microporosity and macroporosity due to grain production systems with forages were not severe enough to cause soil degradation. The soil bulk density in the production systems with perennial forages was lower and total porosity and macroporosity, in the 0-2 cm layer, higher than in the production systems of grain or of grain with annual forages.
  • Authors:
    • Pérez, R.
    • Ayuso, J. L.
    • Taguas, E. V.
    • Yuan, Y.
    • Peña, A.
  • Source: Earth Surface Processes and Landforms
  • Volume: 34
  • Issue: 5
  • Year: 2009
  • Summary: Despite the high risk of erosion in olive Orchards located in mountainous areas in Spain, little research has been carried out to account for the complexity and interaction of the natural processes of runoff and soil erosion on the catchment scale or small catchment scale. In this Study, a microcatchment of 6.7 ha in a mountainous area under no-tillage farming with hare soil was Set Up to record runoff and sediment. Soil erosion and runoff patterns were monitored Over a two-year period. Totally events were observed. The data were analysed, and then Used to calibrate the, AnnAGNPS model, which allowed Lis to complete the data period and describe the hydrological and erosive behaviour on a monthly and annual basis. A high variability in catchment responses was observed, due to differences in the storms and to the effect of the surface Soil moisture content. Maximum intensities of 10 and 30 min determined the final runoff Values while the total sediment leads were dependent on the rainfall depth. The impact of management on the reduction of porosity can explain the relationship between runoff and intensity in the microcatchment. However, the impact of the spatial scale meant that the transport of sediment required substantial rainfall depths to ensure a Continuous flew front the hillslopes. The results of the calibration (E > 0.60 and r > 0.75) on the event and monthly scale confirmed the applicability of AnnAGNPS to predict runoff and erosion in the microcatchment. The predicted average runoff coefficient was 3.3% for the study period and the total average Sediment loads, 1.3 Mg/ha/yr. Despite these low Values, the model Simulation Showed that much larger runoff coefficients and soil losses can be expected for periods with several consecutive years in which the annual rainfall depth was over 500 mm). The use of cover is recommended to prevent the high levels of erosion associated with these conditions. Copyright (C) 2009 John Wiley & Sons, Ltd,
  • Authors:
    • Chen, P.
    • Gbur, E. E.
    • Popp, J. H.
    • Brye, K. R.
    • Verkler, T. L.
    • Amuri, N.
  • Source: Journal of Sustainable Agriculture
  • Volume: 33
  • Issue: 7
  • Year: 2009
  • Summary: Soil, water, and air quality can be positively impacted by alternative crop residue management practices that return residue to the soil. Double-crop production systems, particularly those with a grass included in the rotation, rely on successful residue management practices. Soil quality and overall soil tilth are often low in regions with a long history of intensely cultivated, row-crop production, such as in the Mississippi River Delta region of the mid-South. Therefore, the objective of this study was to evaluate the effects of alternative residue (i.e., tillage, residue burning, and residue level) and water management practices on soil properties, soybean [ Glycine max (L.) Merr.] production, and net economic returns, over two consecutive rotations in a wheat ( Triticum aestivum L.) - soybean double-crop system in the Mississippi River Δ region of eastern Arkansas. Initiated in 2001, this study reports results from years 4 and 5 of the experiment. Residue management effects were inconsistent among soil properties and years, and differences were generally agronomically non-significant. Averaged across irrigation treatments, soybean yield was unaffected by tillage, burning, and residue level either year. Within the non-irrigated treatment, conventionally tilled (CT) soybean yield was 38% greater ( p
  • Authors:
    • da S. Volk, L. B.
    • Cogo, N. P.
    • Volk, L. B. da S.
  • Source: Revista Brasileira de Ciência do Solo
  • Volume: 33
  • Issue: 5
  • Year: 2009
  • Summary: This work was accomplished with the purpose of establishing quantitative relationships between the D 50 index of the size distribution of the soil-eroded sediments, the runoff velocity, the SR index of the tillage-induced soil surface roughness, and the mean weight diameter (MWD) of the soil aggregates, in a soil submitted to different forms of management. The study was developed in the field, at the Agricultural Experimentation Station of the Federal University of Rio Grande do Sul (EEA/UFRGS), in Eldorado do Sul (RS), Brazil, by applying simulated rainfall on an Ultisol with a sandy clay loam texture in the surface layer and 0.115 m m -1 average slope steepness. This soil had been put into agricultural use by different manners (continuous and discontinued cultivation), with different crop sequences (winter and summer, grass and legume crop species, planted in rows, using no-tillage), for a 7.5 year period (starting at the original condition of native pasture). Seven erosion tests were performed in the study, each one of them at 63.5 mm h -1 rainfall intensity and 1.5 h duration, using the rotating-boom rainfall simulator and 3.5*11.0 m experimental plots. The referred erosion tests were performed in the following soil surface physical conditions: (a) non-mobilized soil, with complete and no cover by crop residues, and (b) soil successively mobilized by the passage of a light disc-harrow (five times, one at a time), with no cover. It was observed that the crop sequences provided values of the MWD index significantly different each other, which reflected in significantly different values of the SR index and, as consequence, of the runoff velocity and the D 50 index, with the sequences with none or less time of discontinued cultivation (in the last period of the research) having produced the best results. In the non-mobilized, completely mulch-covered soil, with a firm and smooth surface, the mulch of crop residues was the dominant factor either in reducing the runoff velocity or in trapping the eventually detached soil particles of larger size, which led to very small values of the D 50 index. In the non-mobilized, uncovered soil, where runoff reached its highest velocities, the size of the eroded sediments was determined by the consolidation of the soil surface and by the values of the MWD index, being the smaller for the greater values of the two last variables mentioned. Yet in the soil successively mobilized by the one at a time passage of a light disc-harrow and bare, with a loose and rough surface, the roughness of the soil surface created by tillage was the dominant factor either in reducing the runoff velocity or in trapping the detached soil particles of larger size, which increased the percentage of eroded sediments
  • Authors:
    • Tarkalson, D. D.
    • Shapiro, C. A.
    • Hergert, G. W.
    • Ferguson, R. B.
    • Dobermann, A. R.
    • Wortmann, C. S.
    • Walters, D. T.
  • Source: Agronomy Journal
  • Volume: 101
  • Issue: 3
  • Year: 2009
  • Summary: Nutrient management recommendations may change as yield levels and efficiency of crop production increase. Recommendations for P, K, and S were evaluated using results from 34 irrigated corn ( Zea mays L.) trials conducted in diverse situations across Nebraska. The mean yield was 14.7 Mg ha -1 with adequate fertilizer applied. The median harvest index values were 0.52, 0.89, 0.15, and 0.56 for biomass, P, K, and S, respectively. Median grain yields were 372, 49, and 613 kg kg -1 of aboveground plant uptake of P, K, and S, respectively. The estimated critical Bray-1 P level for corn response to 20 kg P ha -1 was 20 mg kg -1 when the previous crop was corn compared with 10 mg kg -1 when corn followed soybean [ Glycine max (L.) Merr.]. Soil test K was generally high with only three site-years
  • Authors:
    • He, J.
    • Wang, X. Y.
    • Gao, H. W.
    • Li, H. W.
    • Yao, Z. L.
  • Source: Soil Research
  • Volume: 47
  • Issue: 8
  • Year: 2009
  • Summary: The furrow opening configuration used by no-till seeders can have a major effect on crop emergence in conservation tillage systems. This is particularly important in annual double-cropping regions (winter wheat and summer maize) of northern China where large volumes of residue remain on the soil surface after maize harvesting. This problem has been investigated using 3 different opening configurations for no-till wheat seeding near Beijing in 2004-05 and 2005-06, and assessing performance in terms of soil disturbance, residue cover index, soil cone index, fuel consumption, winter wheat emergence, plant growth, and subsequent yield. In this cropping system, the single-disc opening configuration significantly decreased mean soil disturbance and increased residue cover index compared with the combined strip-chop and strip-till opening configurations, but winter wheat emergence was 6-9% less, probably due to greater levels of residue cover and greater seed zone soil cone index. Winter wheat growth after seeding in combined strip-chop and strip-till seeded plots was faster than that in single-disc seeded plots and mean yield was greater. The most suitable furrow opening configuration in heavy residue cover conditions appeared to be the strip-chop one, which can provide similar crop performance with marginally better fuel economy than the strip-till opening configuration. These results should be seen as preliminary, but they are still valuable for the design and selection of no-till wheat seeders for double cropping in this region of China.