• Authors:
    • Mundra, M. C.
    • Singh, B. P.
    • Gupta, S. C.
  • Source: Crop Research (Hisar)
  • Volume: 25
  • Issue: 3
  • Year: 2003
  • Summary: Field experiments were conducted in Haryana, India, on sandy loam soil to investigate the suitability of various cropping systems under irrigated conditions in an semi-arid environment. Thirteen kharif-rabi-summer cropping systems were tested and recommended rates of NPK fertilizers were applied to each crop. Among the cropping systems, pearl millet-potato-tomato, pearl millet-potato-green gram, cotton-wheat and soyabean-wheat-fodder cowpea produced yields of 13 948, 10 374, 8965 and 8316 kg/ha, respectively, on an equivalent basis. The lowest yield (6065 kg/ha) was obtained in the pearl millet-Indian mustard system. The maximum net return of Rs. 42 462/ha, benefit:cost ratio of 2.43, system productivity of 42.26 kg/ha per day, land use efficiency of 90.41% and total energy of 48 521 Cal * 100 calories were obtained from the pearl millet-potato-tomato system. The maximum stability indices of 0.98, 0.96 and 0.79 for kharif, rabi and summer seasons, respectively, were obtained in the pearl millet-mustard and pearl millet-mustard-fodder maize systems. The maximum system index of 0.90 was obtained in the fodder sorghum-wheat system followed by soyabean-wheat-fodder cowpea with 0.83. Pearl millet-potato-greengram showed the maximum risk of Rs. 10 915/ha, while the lowest risk of Rs. 3847/ha was obtained in the pigeon pea-wheat system.
  • Authors:
    • Grove, J. H.
    • Diaz-Zorita, M.
  • Source: Soil & Tillage Research
  • Volume: 65
  • Issue: 1
  • Year: 2002
  • Summary: The western part of the Argentine Pampas is a subhumid and semiarid region consisting of extensive plain with deep sandy and sandy-loam soils. The agricultural system includes pastures in rotation with annual grain crops and grazed crops or continuous annual row cropping. The objective of this review was to present and discuss changes in soil properties due to different soil management systems, mainly no-tillage practices, in the western part of the Argentine Pampas. The effects of tillage, crop sequences under no-till, and grazing on soil properties and crop productivity have been studied since 1990 on loamy and sandy Haplic Phaeozem (Typic Hapludolls and Entic Hapludolls) and Haplic Kastanozem (Typic Haplustolls). A database developed from the yield and soil test records of growers affiliated with Regional Consortium for Agricultural Experimentation (CREA) were also utilized in the study. The results showed that soil organic C (SOC) content depends both on soil texture and soil management. SOC decreases when the length of the row crop cycle increases and also in moldboard plow and chisel-tillage systems. Pastures and no-till row crop sequences with more years of maize (Zea mays L.) and wheat (Triticum aestivum L.), than sunflower (Helianthus annus L.) or soybean (Glycine max (L.) Merrill) tended to increase the SOC content in the 0-20 cm layer. Deep tillage of no-till soils with compacted layers improved maize dry matter production but, in the same experiment, yield was increased more by nitrogen fertilization than by subsoil tillage. The grazing of crop residues increases the soil bulk density only in the 0-5 cm layer of tilled soils, but did not significantly change bulk density on soils under continuous no-till. Crop productivity was related to SOC content of the 0-20 cm layer of the soils. Due to the positive effect of SOC on crop yields, no-till soil management and pasture-annual row crop rotations are two practices that permit the development of sustainable production systems in the western part of the Argentine Pampas.
  • Authors:
    • Lal, R.
    • Kimble, J. M.
    • Follett, R. F.
  • Year: 2001
  • Summary: Grazing lands represent the largest and most diverse land resource-taking up over half the earth's land surface. The large area grazing land occupies, its diversity of climates and soils, and the potential to improve its use and productivity all contribute to its importance for sequestering C and mitigating the greenhouse effect and other conditions brought about by climate change. The Potential of U.S. Grazing Lands to Sequester Carbon and Mitigate the Greenhouse Effect gives you an in-depth look at this possibility.
  • Authors:
    • Ries, R.
    • Merrill, S.
    • Krupinsky, J.
    • Tanaka, D.
  • Source: Proceedings of the 5th International Safflower Conference, Williston, North Dakota and Sidney, Montana, USA, 23-27 July, 2001. Safflower: a multipurpose species with unexploited potential and world adaptability
  • Year: 2001
  • Summary: Safflower is a good crop to include in cereal based cropping systems in the Northern Great Plains of the USA and Canada because it is adapted to semi-arid regions of the world. No-till field research was conducted 11 km southwest of Mandan, ND to determine the influences of previous crop and crop residue on safflower ( Carthamus tintorius) production. Four replicates of safflower were seeded over ten crop residues [canola ( Brassica napus), crambe ( Crambe abysinnica), dry pea ( Pisum sativum L.), dry bean ( Phaseolus vulgaris L.), flax ( Linum usitatissimum L.), safflower, soybean (Glycine max (L.) Merr.), sunflower ( Helianthus annuus L.), wheat ( Triticum aestivum L.), and barley ( Hordeum vulgare L.)] in 1999 and 2000. Averaged over the two years, surface residue cover after seeding safflower was the highest for wheat, barley, and flax (95 to 86%) and the lowest for dry pea, dry bean, and sunflower (82 to 31%). Safflower production after flax, barley, wheat, and dry pea was 220 to 150% greater than safflower production after safflower. The sustainability of diversified cropping systems that include safflower will be determined by the previous crop and crop residues and the crop sequence in which safflower is grown.
  • Authors:
    • Avci, M.
  • Source: Efficient soil water use: the key to sustainable crop production in the dry areas of West Asia, and North and Sub-Saharan Africa. Proceedings of the workshops organized by the Optimizing Soil Water Use Consortium, Niamey, Niger, 26-30 April, 1998, Amman, J
  • Year: 1999
  • Summary: Semi-arid areas cover about 55% of Turkey and are mainly found in the Central Anatolian Plateau. The main crop production systems are fallow/wheat and legume/wheat. Wheat is generally prone to droughts, which severely affect the yields. Research on soil moisture use in fallow-wheat systems started in the 1930s. Its focus was on water interception and conservation techniques, and detailed research on rainfall interception led to practices which have been adopted by most of the plateau farmers. In the 1980s research focused on the replacement of fallow by a crop in the rotation systems. In most areas, fallow can best be replaced in terms of yield by forage crops and economically by edible legumes. Characterization of the other regions will identify fallow or continuous cropping target areas, and extrapolation of research results to them. Regarding technologies, the importance of terracing for moisture conservation increases with the degree of slope and the occurrence of erosive rainfall. Contour tillage and sowing were effective only on steep slopes. Future research is needed on supplemental irrigation to increase the water-use efficiencies of the wheat and barley varieties especially developed for irrigation.
  • Authors:
    • Heinemeyer, O.
    • Lyon, D. J.
    • Drijber, R. A.
    • Doran, J. W.
    • Mosier, A. R.
    • Kessavalou, A.
  • Source: Journal of Environmental Quality
  • Volume: 27
  • Issue: 5
  • Year: 1998
  • Summary: Cropping and tillage management can increase atmospheric CO2, N2O, and CH4 concentrations, and contribute to global warming and destruction of the ozone layer. Fluxes of these gases in vented surface chambers, and water-filled pore space (WFPS) and temperature of survace soil were measured weekly from a long-term winter wheat (Triticum aestivum L.)-fallow rotation system under chemical (no-tillage) and mechanical tillage (noninversion subtillage at 7 to 10 cm or moldboard plowing to 15 cm) follow management and compared with those from "native" grass sod at Sidney, NE, from March 1993 to July 1995. Cropping, tillage, within-field location, time of year, soil temperature, and WFPS influenced net greenhouse gas fluxes. Mean annual interrow CO2 emissions from wheat-fallow ranged from 6.9 to 20.1 kg C ha-1 d-1 and generally increased with intensity and degree of tillage (no-till least and plow greatest). Nitrous oxide flux averaged summer > autumn > winter. Winter periods accounted for 4 to 10% and 3 to 47% of the annual CO2 and N2O flux, respectively, and 12 to 21% of the annual CH4 uptake. Fluxes of CO2 and N2O, and CH4 uptake increased linearly with soil temperature. No-till fallow exhibited the least threat to deterioration of atmospheric or soil quality as reflected by greater CH4 uptake, decreased N2O and CO2 emissions, and less loss of soil organic C than tilled soils. However, potential for increased C sequestration in this wheat-fallow system is limited due to reduced C input from intermittent cropping.
  • Authors:
    • Peterson, G. A.
    • Lyon, D. J.
    • Halvorson, A. D.
    • Leavitt, S. W.
    • Paul, E. A.
    • Follett, R. F.
  • Source: Soil Science Society of America Journal
  • Volume: 61
  • Issue: 4
  • Year: 1997
  • Summary: The purposes of this study were to improve knowledge of regional vegetation patterns of C-3 and C-4 plants in the North American Great Plains and to use delta(13)C methodology and long-term research sites to determine contributions of small-grain crops to total soil organic carbon (SOC) now present, Archived and recent soil samples were used, Detailed soil sampling was in 1993 at long-term sites near Akron, CO, and Sidney, NE, After soil sieving, drying, and deliming, SOC and delta(13)C were determined using an automated C/N analyzer interfaced to an isotope-ratio mass spectrometer, Yield records from long-term experimental sites were used to estimate the amount of C-3 plant residue C returned to the soil, Results from delta(13)C analyses of soils from near Waldheim, Saskatchewan, to Big Springs, TX, showed a strong north to south decrease in SOC derived from C-3 plants and a corresponding increase from C-4 plants. The delta(13)C analyses gave evidence that C-3 plant residue C (possibly from shrubs) is increasing at the Big Springs, TX, and Lawton, OK, sites, Also, delta(13)C analyses of subsoil and topsoil layers shows evidence of a regional shift to more C-3 species, possibly because of a cooler climate during the past few hundreds to thousands of years, Data from long-term research sites indicate that the efficiency of incorporation of small-grain crop residue C was about 5.4% during 84 Jr at Akron, CO, and about 10.5% : during 20 yr at Sidney, NE, The C-14 age of the SOC at 0- to IO-tm depth was 193 yr and at 30 to 45 cm was 4000 yr; C-14 age of nonhydrolyzable C was 2000 and 7000 yr for these same two respective depths, Natural partitioning of the C-13 isotope by the photosynthetic pathways of C-3 and C-4 plants provides a potentially powerful tool to study SOC dynamics at both regional and local scales.
  • Authors:
    • Unger, P. W.
    • Alemu, G.
    • Jones, O. R.
  • Source: Communications in Soil Science and Plant Analysis
  • Volume: 28
  • Issue: 1-2
  • Year: 1997
  • Summary: Soil and water conserving practices must be used to sustain dryland crop production in semiarid regions. In this 1994 study, we evaluated the effects of different cropping system and tillage method treatments on surface residue cover, organic matter content, aggregation, and water infiltration for a soil used for grain sorghum [Sorghum bicolor (L.) Moench] production in the United States Southern Great Plains from 1982 to 1994. Cropping systems were continuous sorghum (CS) and winter wheat (Triticum aestivum L.)-fallow-grain sorghum-fallow (designated WSF) and tillage methods were no-tillage (NT) and stubble mulch tillage (SMT). Treatments were CS-NT, CS-SMT, WSF-NT, and WSF-SMT. Surface residue cover before planting sorghum was >70% with CS-NT and WSF-NT, 29% with CS-SMT, and 12% with WSF-SMT. Surface cover after planting was approximate to 50% with both NT treatments, whereas amounts with other treatments were similar to those before planting. Soil organic matter contents (0- to 10-cm depth) were greater on CS than on WSF plots, but were not affected by tillage method in either cropping system. Water stable aggregation (0- to 2-cm depth) was greater with SMT than with NT in both cropping systems, but differences between cropping systems were not significant. Dry aggregates were smaller with NT than with SMT. Water infiltration was or tended to be greater on CS than on WSF plots, apparently because the WSF plots contained more water when infiltration was measured. Infiltration was not affected by tillage method, apparently because the greater amount of surface residues on NT plots counteracted the less water stable aggregates and smaller dry aggregates that had potential for reducing infiltration on the NT plots. This study indicates that no cropping system-tillage method combination treatment had a consistently beneficial or detrimental effect on soil conditions. In conclusion, both cropping systems (CS and WSF) and both tillage methods (NT and SMT) are suitable for conserving soil and water resources and, therefore, for sustaining dryland crop production in the semiarid United States Southern Great Plains.
  • Authors:
    • Lamm,F. R.
    • Manges,H. L.
    • Stone,L. R.
    • Khan,A. H.
    • Rogers,D. H.
  • Source: Transactions of the ASAE
  • Volume: 38
  • Issue: 2
  • Year: 1995
  • Summary: Irrigation development during the last 50 years has led to overdraft in many areas of the large Ogallala aquifer in the central United States. Faced with the decline in irrigated acres, irrigators and wafer resource personnel are examining many new techniques to conserve this valuable resource. A three-year study (1989 to 1991) was conducted on a Keith silt loam soil (Aridic Argiustoll) in northwest Kansas to determine the water requirement of corn (Zea mays L.) grown using a subsurface drip irrigation (SDI) system. A dryland control and five irrigation treatments, designed to meet from 25 to 125% of calculated evapotranspiration (ET) needs of the crop were examined. Although cumulative evapotranspiration and precipitation were near normal for the three growing seasons, irrigation requirements were higher than normal due to the timing of precipitation and high evapotranspiration periods. Analysis of the seasonal progression of soil water revealed the well-watered treatments (75 to 125% of ET treatments) maintained stable soil water levels above approximately 55 to 60% of field capacity for the 2.4-m soil profile; while the deficit-irrigated treatments (no irrigation to 50% of ET treatments) mined the soil water. Corn yields were highly linearly related to calculated crop water use, producing 0.048 Mg/ha of grain for each millimeter of water used above a threshold of 328 mm. Analysis of the calculated water balance components indicated that careful management of SDI systems can reduce net irrigation needs by nearly 25%, while still maintaining top yields of 12.5 Mg/ha. Most of these water savings can be attributable to minimizing nonbeneficial water balance components such as soil evaporation and long-term drainage. The SDI system is one technology that can make significant improvements in water use efficiency by better managing the water balance components.
  • Authors:
    • Zuberer, D. A.
    • Hons, F. M.
    • Franzluebbers, A. J.
  • Source: Soil Science Society of America Journal
  • Volume: 58
  • Issue: 6
  • Year: 1994
  • Summary: Crop management strategies that alter the timing, placement, quantity, and quality of crop residue input can affect the size, turnover, and vertical distribution of the active and passive pools of soil organic matter (SOM). Our objectives were to quantify long-term changes in soil organic, soil microbial biomass (SMB), and mineralizable C and N in continuous wheat (Triticum aestivum L.), continuous wheat/soybean [Glycine max (L.) Merr.], and wheat/soybean-sorghum [Sorghum bicolor (L.) Moench.] sequences under conventional tillage (CT) and no tillage (NT) with and without N fertilizer. A Weswood silty clay loam (fine, mixed, thermic Fluventic Ustochrept) in southcentral Texas was collected from a 9-yr field study. Soil microbial biomass C (SMBC) and N (SMBN) were determined with the chloroform fumigation-incubation method and mineralizable C and N were determined from 10-d aerobic incubations at 25{degrees}C. More crop residue C input was retained as soil organic C (SOC), SMBC, and mineralizable C under NT than under CT. Soil organic C, SMBC, and mineralizable C at a depth of 0 to 50 mm were 33 to 125% greater under NT than under CT. Increasing cropping intensity increased SOC up to 22%, SMBC up to 31%, and mineralizable C up to 27% under NT. Differences in crop management systems significantly altered SMB and the associated mineralizable N level, which supplies crops with mineral N. High clay content soils of central Texas can be effectively managed to increase the active and passive pools of SOM using minimal fallow with NT.