• Authors:
    • Halvorson, A. D.
    • Archer, D. W.
  • Source: Soil Science Society of America Journal
  • Volume: 74
  • Issue: 2
  • Year: 2010
  • Summary: Recent soil and crop management technologies have potential for mitigating greenhouse gas emissions; however, these management strategies must be profitable if they are to be adopted by producers. The economic feasibility of reducing net greenhouse gas emissions in irrigated cropping systems was evaluated for 5 yr on a Fort Collins clay loam soil (a fine-loamy, mixed, superactive, mesic Aridic Haplustalf). Cropping systems included conventional tillage continuous corn ( Zea mays L.) (CT-CC), no-till continuous corn (NT-CC), and no-till corn-bean (NT-CB) including 1 yr soybean [ Glycine max (L.) Merr.] and 1 yr dry bean ( Phaseolus vulgaris L.). The study included six N fertilization rates ranging from 0 to 246 kg ha -1. Results showed highest average net returns for NT-CB, exceeding net returns for NT-CC and CT-CC by US$182 and US$228 ha -1, respectively, at economically optimum N fertilizer rates. Net global warming potential (GWP) generally increased with increasing N fertilizer rate with the exception of NT-CC, where net GWP initially declined and then increased at higher N rates. Combining economic and net GWP measurements showed that producers have an economic incentive to switch from CT-CC to NT-CB, increasing annual average net returns by US$228 ha -1 while reducing annual net GWP by 929 kg CO 2 equivalents ha -1. The greatest GWP reductions (1463 kg CO 2 equivalents ha -1) could be achieved by switching from CT-CC to NT-CC while also increasing net returns, but the presence of a more profitable NT-CB alternative means NT-CC is unlikely to be chosen without additional economic incentives.
  • Authors:
    • Raut, D. V.
    • Bhopale, A. A.
    • Awaghad, P. R.
    • Rathod, A. L.
  • Source: Annals of Plant Physiology
  • Volume: 24
  • Issue: 1
  • Year: 2010
  • Summary: The study of cropping pattern assumes a great significance as it is one of the important path for balanced development of agriculture to meet the human requirements. In this context, an effort has been made to examine the changes in cropping pattern in Akola district (M.S.) extent of crop diversification and economics. The present study was based on secondary data collected from different government publications. The data covered a period of 21 years i.e. 1986-87 to 2006-07. In all 8 crops were considered for study. Simple tabular analysis was used to examine the changes in cropping pattern in various tahsils of Akola district (M.S.). In order to study the extent of crop diversification Herfindahl index has been used. In order to study the economics of crop diversification, land concentration ratio in tahsils with comparative advantage was computed for selected years. Tahsil wise analysis showed that the area under kharif jowar has found to be decreased in all the tahsils of Akola district Area under tur crop was decreased in Barshitakali and patur tahsil. The area under mung has found to be increased in all the tahsils. Cotton still remains as major crop of the district. In majority of tahsils of Akola district i.e. Balapur, Barshitakali and Patur, Crop diversification has significantly increased during the study period. While in Murtizapur tahsil it has showed more or less stationery diversification. The results of analysis of economics of crop diversification revealed that, no one crop has shown increasing or decreasing trend of land concentration ratio over the time. Particular crop was beneficial in the particular year in the district.
  • Authors:
    • Domua, C.
    • Borza, I.
    • Ardelean, I.
    • Domuta, C.
    • Bandici, G.
    • Radu, B.
  • Source: Natural Resources and Sustainable Development
  • Issue: 2010
  • Year: 2010
  • Summary: The paper sustain the importance of the crop rotation on quality of the wheat yield and is based on the results carried out during 2003-2006 in a long term trial out placed on the preluvosoil from Oradea in 1990. Both in nonirrigated and irrigated conditions the smallest values of the protein, wet gluten and dry gluten were obtained in wheat monocrop; the values increased in the crop rotation wheat maize and the biggest values were registered in the crop rotation wheat-maize-soybean.
  • Authors:
    • Bartosik, R.
  • Source: Julius-Kühn-Archiv
  • Issue: 425
  • Year: 2010
  • Summary: Concerning grain production, South America is divided in two main regions: (1) the Mercosur region (Argentina, Brazil, Uruguay and Paraguay) which produces more than 250 million tonnes of grains and oilseeds, and (2) the Andes Mountain region countries, which are net importers of these products. The main challenges related to grain postharvest that South America is facing are to minimize the quality and quantity losses; improve the food safety; enhance the capability for segregation and traceability of identity preserved (IP) grains; and incorporate technology to maintain the overall efficiency of the postharvest system. Among the critical points affecting the efficiency of the system are the shortage of permanent storage capacity; large storage structures which affects the segregation of IP grains; deficient transportation system (roads and railroads); poor management of integrated pest control system; and unsatisfied demand of formal and informal education in suitable grain postharvest technologies and practices. However, the region remains highly competitive in producing and delivering food for the rest of the world and it has demonstrated high capacity for incorporating cost efficient grain handling technologies. As a result, one of the main changes in the region was the appearance of the silobag system for temporary storage of dry grain and oilseeds. Each silobag can hold approximately 200 tonnes of wheat and with the available handling equipment is quite simple to load and unload. During the 2008 harvest season, more than 33 million tonnes of grain were stored in these plastic bags in Argentina (including corn, soybean, wheat, sunflower, malting barley, canola, cotton seed, rice, lentils, sorghum, beans and even fertilizers). The silobag technology is also being adopted not only in neighbor countries, but also in countries around the world such as the USA, Mexico, South Africa, Australia, Russia and Ukraine, among others.
  • Authors:
    • Maghirang, R. G.
    • Casada, M. E.
    • Boac, J. M.
    • Harner, J. P.,III
  • Source: Transactions of the ASABE
  • Volume: 53
  • Issue: 4
  • Year: 2010
  • Summary: Experimental investigations of grain flow can be expensive and time consuming, but computer simulations can reduce the large effort required to evaluate the flow of grain in handling operations. Published data on material and interaction properties of selected grains and oilseeds relevant to discrete element method (DEM) modeling were reviewed. Material properties include grain kernel shape, size, and distribution; Poisson's ratio; shear modulus; and density. Interaction properties consist of coefficients of restitution, static friction, and rolling friction. Soybeans were selected as the test material for DEM simulations to validate the model fundamentals using material and interaction properties. Single- and multi-sphere soybean particle shapes, comprised of one to four overlapping spheres, were compared based on DEM simulations of bulk properties (bulk density and bulk angle of repose) and computation time. A single-sphere particle model best simulated soybean kernels in the bulk property tests. The best particle model had a particle coefficient of restitution of 0.6, particle coefficient of static friction of 0.45 for soybean-soybean contact (0.30 for soybean-steel interaction), particle coefficient of rolling friction of 0.05, normal particle size distribution with standard deviation factor of 0.4, and particle shear modulus of 1.04 MPa.
  • Authors:
    • Domuta, C.
    • Sandor, M.
    • Bara, L.
    • Bara, C.
    • Bara, V.
    • Domuta, C.
    • Borza, I. M.
    • Brejea, R.
    • Vuscan, A.
  • Source: Analele Universităţii din Oradea, Fascicula: Protecţia Mediului
  • Volume: 15
  • Year: 2010
  • Summary: The paper based on the researche carried out in the Agricultural Research and Development Station Oradea in the long term trial placed in 1990 on a preluvosoil. Two factors were studied: crop rotation (maize-monocrop; maize-wheat; maize-soybean-wheat) and water regime (unirrigated and irrigated). In comparison with unirrigated and irrigated monocrop, in the maize-wheat crop and especially in the maize-soybean-wheat crop rotation very significant yield gains were obtained all the three years. The irrigation determined the yield gains very significant statistically every year and in every crop rotation. The smallest protein content and protein production were registered in the variant with maize monocrop and the biggest in the variant with wheat-maize-soybean crop. The irrigation determined the increase of the protein content.
  • Authors:
    • Kochsiek, A. E.
    • Knops, J. M. H.
    • Walters, D. T.
    • Arkebauer, T. J.
  • Source: Agricultural and Forest Meteorology
  • Volume: 149
  • Issue: 11
  • Year: 2009
  • Summary: The litter carbon (C) pool of a single litter cohort in an agroecosystem is the difference between net primary productivity and decomposition and comprises 11-13% of the total C pool (litter and soil 0-15 cm depth) post-harvest. This litter-C pool is highly dynamic and up to 50% can be decomposed in the first 12 months of decomposition. Thus, understanding litter-C dynamics is key in understanding monthly and annual total ecosystem carbon dynamics. While the effects of management practices such as irrigation and fertilization on productivity are well understood, the effects on decomposition are less studied. While irrigation and fertilization increase productivity, this will only lead to increased litter-C residence time and litter-C pool accretion if these techniques do not also result in equivalent or greater increases in decomposition. Management could potentially have impacts on litter-C accretion by increasing litter inputs, changing plant-C allocation, plant tissue quality, or decomposition rates. We examined carbon loss of one annual cohort of maize litter using in situ nylon litter bags for 3 years in three no-till fields with differing management regimes: irrigated continuous maize with a pre-planting fertilization application and two fertigation events, irrigated maize-soybean rotation with the same fertilization regime as the irrigated continuous maize management regime, and rainfed maize-soybean rotation with a single pre-planting fertilization event. We addressed the effects of these different management regimes on net primary productivity and litter inputs, litter nitrogen (N) concentrations and carbon quality measures, plant C allocation, decomposition rates and the potential changes in the overall litter-C balance. We found that irrigation/fertigation management increased litter inputs, led to changes in plant tissue quality, had no effect on carbon allocation, and increased decomposition rates. This balance of both greater litter inputs and outputs of C from the irrigated management regimes led to a similar litter-C balance for this litter cohort in the irrigated and rainfed management regimes after 3 years of decomposition. Our data clearly show that merely increasing litter-C inputs through irrigation/fertigation practices is not sufficient to increase litter-C residence time because decomposition rates also increase. Therefore, close monitoring of decomposition rates is essential for understanding litter-C pool dynamics.
  • Authors:
    • Nel, A. A.
  • Source: South African Journal of Plant and Soil
  • Volume: 26
  • Issue: 3
  • Year: 2009
  • Summary: Crop rotation is known to enhance crop yields. It is therefore recommended, regardless of rainfall and soil type, as a counter measure for the risks associated with monoculture maize ( Zea mays). Experience in the western Highveld where rainfall is low and erratic, has shown that the yield of maize does not necessarily improve as expected when preceded by alternative crops, but in fact, is often reduced. The present study was initiated to determine the effect of crop rotation with cowpea, groundnut, soyabean, sunflower or fallow on the yield and rainfall use efficiency of maize under marginal conditions on the western Highveld. Dryland maize was grown in five crop rotation systems on Mutton type soils at the farms Holfontein (four years) and Noodshulp (five years), both situated close to Ottosdal (2649′S; 2600′E). The soil profiles had an effective depth of >1.5 m at Holfontein and 1.25 m at Noodshulp. Crop rotation systems consisted of two-year rotations of cowpea-, groundnut, soybean-, sunflower-, and fallow-maize; as well as groundnut-, soybean-, and sunflower-fallow. A continuous monoculture maize treatment was included to serve as control. At Noodshulp where the rainfall was more variable, crop rotation induced maize yield deviations from the monoculture control occurred more often than at Holfontein. Apart from yield neutral and positive effects, instances of a decline in maize yield in some years due to crop rotation with cowpea, groundnut and sunflower also occurred. Taking the long-term rotational effect and the possibility of a yield decline into account, fallowing and the rotational crops ranked from best to worse were groundnut, soyabean, fallowing, cowpea and sunflower. The long-term effect of cowpea on the yield of maize was neutral and that of sunflower negative. The mean rainfall use efficiency of monoculture maize was, with the exception of maize preceded by groundnut, similar to that of maize grown in rotation.
  • Authors:
    • Sousa, D. M. G. de
    • Rein, T. A.
  • Source: Informações Agronômicas
  • Issue: 126
  • Year: 2009
  • Summary: Soyabean monoculture with inadequate agricultural practices has resulted in losses of soil organic matter in the Brazilian cerrado, especially in sandy soils. This has led to erosion, reduced cation exchange capacity and water storage, and diminished fertilizer use efficiency. One of the ways of avoiding the loss of soil organic matter is to reduce tillage, as in the system of direct (as opposed to conventional) planting, and the use of this system is growing in the cerrado region. This paper reviews work that has been done on the correction of soil acidity and fertilizing with macronutrients in the direct planting system, both before and after crop establishment. The section on soil acidity discusses both surface (0-20 cm) and subsurface (20-60 cm) acidity, and the effects of correction with limestone or gypsum under conventional and no tillage systems, and on cotton and soyabean yields under a direct planting system. The section on fertilizers looks at the effects of liming, conventional and no tillage systems and dry farming on soil macronutrient content (with particular reference to nitrogen, phosphorus and potassium) and crop yield (with data for maize). Soil organic matter content is also compared under conventional and no tillage systems.
  • Authors:
    • Gomes, A. da S.
    • Vernetti Junior, F. de J.
    • Schuch, L. O. B.
  • Source: Revista Brasileira de Agrociencia
  • Volume: 15
  • Issue: 1/4
  • Year: 2009
  • Summary: In the state of Rio Grande do Sul, Brazil, there are 5,5 million ha of tilled plain soils that have been partly cropped with irrigated rice ( Oryza sativa L.), the remainder area lodging extensive beef cattle raising. This research was undertaken aiming chiefly to identify one or more technical solutions to the agribusiness associated with the agro-ecosystem of the "Temperate Climate region". The work was carried out at experimental area of Lowland Agricultural Research Station of Embrapa Temperate Climate (31degrees 52′S; 52degrees 21′24W), Brazil. The experiment was planned in a split-plot randomized blocks design with three replications and performed along ten years. The treatments were successive winter and spring-summer crops growing during five years, followed by two years of no-cropping and then three years of irrigated rice crop growing. The spring-summer crops were corn and soybean, besides rice; the winter crops were poaceae (Ps), fabaceae (Fs), species mixtures (Ms), turnip (T) and native grass species (NG). Seeding was performed either by no-ploughing (PD) or conventional (SC). Grain and dry-matter yields were estimated and evaluated. The evaluations were performed by analysis of variance (F and Duncan tests). The results allowed the following conclusions: (1) Ps and Fs had the highest yields; (2) corn yields were higher when its crop followed Fs species and/or Ms; (3) corn crop in tiled plains shows better performance when planted in no-plow; (4) soybean crop following Ps performed better than following Fs; (5) no-plough favors the soybean crop in tilled plains; (6) irrigated rice yields are higher succeeding the corn crop.