• Authors:
    • Sohngen, B.
    • Choi, S. W.
  • Source: Climatic Change
  • Volume: 99
  • Issue: 1-2
  • Year: 2010
  • Summary: This study investigates the cost of soil carbon sequestration in the Midwest US. The model addresses several missing components in earlier analyses: the link between the residue level choice and carbon payments, crop rotations, carbon loss when shifting from conservation to conventional tillage and the spatial pattern of carbon sequestration across different soil types. The results suggest that for $100 per metric ton of carbon, 1.5 million metric tons of carbon could be sequestered per year on the 19.9 million hectares of cropland in the study region. These estimates suggest less carbon potential than existing studies because the opportunity costs associated with conservation tillage are fairly high. Annual carbon rental payments are found to be more efficient, as expected, but for smaller programs, per hectare rental payments are not substantially more costly.
  • Authors:
    • Schulze, E. D.
    • Houwelling, S.
    • Rivier, L.
    • Friedrich, R.
    • Scholz, Y.
    • Pregger, T.
    • Levin, I.
    • Piao, S. L.
    • Peylin, P.
    • Marland, G.
    • Paris, J. D.
    • Ciais, P.
  • Source: Global Change Biology
  • Volume: 16
  • Issue: 5
  • Year: 2010
  • Summary: We analyzed the magnitude, the trends and the uncertainties of fossil-fuel CO2 emissions in the European Union 25 member states (hereafter EU-25), based on emission inventories from energy-use statistics. The stability of emissions during the past decade at EU-25 scale masks decreasing trends in some regions, offset by increasing trends elsewhere. In the recent 4 years, the new Eastern EU-25 member states have experienced an increase in emissions, reversing after a decade-long decreasing trend. Mediterranean and Nordic countries have also experienced a strong acceleration in emissions. In Germany, France and United Kingdom, the stability of emissions is due to the decrease in the industry sector, offset by an increase in the transportation sector. When four different inventories models are compared, we show that the between-models uncertainty is as large as 19% of the mean for EU-25, and even bigger for individual countries. Accurate accounting for fossil CO2 emissions depends on a clear understanding of system boundaries, i.e. emitting activities included in the accounting. We found that the largest source of errors between inventories is the use of distinct systems boundaries (e.g. counting or not bunker fuels, cement manufacturing, non-energy products). Once these inconsistencies are corrected, the between-models uncertainty can be reduced down to 7% at EU-25 scale. The uncertainty of emissions at smaller spatial scales than the country scale was analyzed by comparing two emission maps based upon distinct economic and demographic activities. A number of spatial and temporal biases have been found among the two maps, indicating a significant increase in uncertainties when increasing the resolution at scales finer than ~200 km. At 100 km resolution, for example, the uncertainty of regional emissions is estimated to be 60 g C m-2 yr-1, up to 50% of the mean. The uncertainty on regional fossil-fuel CO2 fluxes to the atmosphere could be reduced by making accurate 14C measurements in atmospheric CO2, and by combining them with transport models.
  • Authors:
    • Grignani, C.
    • Zavattaro, L.
    • Bertora, C.
    • Alluvione, F.
  • Source: Soil Science Society of America Journal
  • Volume: 74
  • Issue: 2
  • Year: 2010
  • Summary: Alternative N fertilizers that stimulate low greenhouse gas emissions from soil are needed to reduce the impact of agriculture on global warming. Corn (Zea mays L.) grown in a calcareous silt loam soil in northwestern Italy was fertilized with a municipal solid waste compost and vetch (Vicia villosa Roth.) green manure. Their potential to reduce N2O and CO2 emissions was compared with that of urea (130 kg N ha-1). Gaseous fluxes were measured for 2 yr in the spring (after soil incorporation of fertilizers) and in summer. In spring, the slow mineralization of compost reduced N2O emissions (0.11% of supplied N) relative to urea (3.4% of applied N), without an increase in CO2 fluxes. Nitrous oxide (2.31% of fixed N) and CO2 emissions from rapid vetch decomposition did not differ from urea. When N2O and CO2 fluxes were combined, compost reduced by 49% the CO2 equivalent emitted following urea application. Vetch did not show such an effect. In summer, no fertilizer effect was found on N2O and CO2 emissions. Compost proved to be potentially suitable to reduce the CO2 equivalent emitted after soil incorporation while vetch did not. For a thorough evaluation, net greenhouse gas emissions assessment should be extended to the entire N life cycle. Differences between calculated N2O emission factors and the default Tier 1 value of the Intergovernmental Panel on Climate Change (1%) confirmed the need for site- and fertilizer-specific estimations.
  • Authors:
    • McDougal, R.
    • Pennock, D.
    • Badiou, P.
  • Year: 2010
  • Authors:
    • Blanco-Canqui, H.
  • Source: Agronomy Journal
  • Volume: 102
  • Issue: 2
  • Year: 2010
  • Summary: Interest in producing cellulosic ethanol from renewable energy sources is growing. Potential energy crops include row crops such as corn (Zea mays L.), perennial warm-season grasses (WSGs), and short-rotation woody crops (SRWCs). However, impacts of growing dedicated energy crops as biofuel on soil and environment have not been well documented. This article reviews the (i) impacts of growing WSGs and SRWCs on soil properties, soil organic carbon (SOC) sequestration, and water quality, and (ii) performance of energy crops in marginal lands. Literature shows that excessive (>= 50%) crop residue removal adversely impacts sod and environmental quality as well as crop yields. Growing WSGs and SRWCs can be potential alternatives to crop residue removal as biofuel. Warm-season grasses and SRWCs can improve soil properties, reduce soil erosion, and sequester SOC. Crop residue removal reduces SOC concentration by 1 to 3 Mg ha(-1) yr(-1) in the top 10 cm, whereas growing WSGs and SRWCs increase SOC concentration while providing biofuel feedstocks. The WSGs can store SOC between 0 and 3 Mg C ha(-1) yr(-1) in the top 5 cm of soil, while the SRWCs can store between 0 and 1.6 Mg ha(-1) yr(-1) of SOC in the top 100 cm. The WSGs and SRWCs have more beneficial effects on soil and environment when grown in marginal lands than when grown in croplands or natural forests. Indeed, they can grow in nutrient-depleted, compacted, poorly drained, acid, and eroded soils. Development of sustainable systems of WSGs and SRWCs in marginal lands is a high priority.
  • Authors:
    • McKenzie, R. H.
    • Bremer, E.
    • Olson, B. M.
    • Bennett, D. R.
  • Source: Canadian Journal of Soil Science
  • Volume: 90
  • Issue: 2
  • Year: 2010
  • Summary: The risk of P leaching increases on land that receives manure at rates sufficient to meet crop N requirements, but calcareous subsoils may minimize P loss due to P adsorption. An 8-yr field experiment was conducted to determine the effects of different rates of manure on the accumulation and leaching of soil P in a coarse-textured (CT) soil and a medium-textured (MT) soil under typical irrigation management in southern Alberta. Treatments included a non-manured control and four rates of cattle ( Bos taurus) manure (20, 40, 60, and 120 Mg ha -1 yr -1, wet-weight basis). In manured treatments, P addition ranged from about 80 to 450 kg P ha -1 yr -1, while P removal by annual cereal silage crops ranged from 15 to 22 kg P ha -1 yr -1. High soil test P (STP) concentrations occurred to a depth of 0.6 m at the CT site and 0.3 m at the MT site. Increase in STP concentration to 0.6 m was equivalent to 43% of net P input, and increase in total soil P was equivalent to 78% of net P input. Non-recovery of net P input suggests that P loss by leaching occurred at these sites and that leaching was more prevalent at the CT site. These calcareous soils have considerable potential to hold surplus P, but may still allow P leaching.
  • Authors:
    • Larney, F. J.
    • McKenzie, R. H.
    • Olson, B. M.
    • Bremer, E.
  • Source: Canadian Journal of Soil Science
  • Volume: 90
  • Issue: 4
  • Year: 2010
  • Summary: Land application of livestock manure has caused concern about excess nutrients in soil and the potential risk to water quality. Application of manure based on crop-nutrient requirements is considered a beneficial management practice. A field study was conducted to assess the feasibility and impact of crop-based N and P application rates of cattle ( Bos taurus) manure and compost for crop productivity and accumulation of extractable soil N and P. The 6-yr (2002-2007), small-plot field study included 10 amendments: control (CONT), annual synthetic fertilizer N (F-N), annual synthetic fertilizer P (F-P), annual synthetic fertilizer N plus P (F-NP), annual N-based manure (M-N), annual P-based manure (M-P), three times the P-based manure once per 3 yr (M-3P), annual N-based compost (C-N), annual P-based compost (C-P), and three times the P-based compost once per 3 yr (C-3P). Amendments were arranged in randomized complete block design with five replicates and applied based on annual soil testing and nutrient recommendations. The test crops were triticale (* Triticosecale rimpaui Wittm.) and barley ( Hordeum vulgare L.) silage managed under irrigation. Dry matter yields for CONT and F-P were significantly smaller than for the other treatments. There were generally no significant differences among the six organic and F-NP amendments. Apparent N recovery (ANR) was greatest for F-NP (45%) and F-N (41%), followed by the P-based organic amendments (26-34%), M-N (15%), and smallest for C-N (10%). Apparent P recovery (APR) was greatest for F-NP (30%) and smallest for M-N (6%) and C-N (4%). The APR for the P-based organic amendments ranged from 14 to 22%. Application of the amendments did not result in the accumulation of excess nitrate N in the soil profile. The M-N and C-N amendments applied for 6 yr increased extractable P in the 0- to 0.15-m soil layer from 12 mg kg -1 to 121 and 156 mg kg -1, respectively. Crop productivity and soil nutrient responses indicated that assumptions made for P and N availability in manure and compost were reasonably accurate. Based on the results, P-based application of manure or compost can achieve optimum crop yield and prevent nutrient build-up in soil. Under the conditions of this study, the amount of land required to accommodate P-based application would be five to seven times more for manure and eight to ten times more for compost compared with N-based application.
  • Authors:
    • Horvath, G. V.
    • Sass, L.
    • Majer, P.
    • Lelley, T.
    • Feherne, J. E.
    • Szenasi, M.
    • Mihaly, R.
    • Lantos, C.
    • Cseuz, L.
    • Pauk, J.
    • Vass, I.
    • Dudits, D.
  • Source: Tagung der Vereinigung der Pflanzenzüchter und Saatgutkau fleute Österreichs
  • Year: 2010
  • Summary: Breeding for drought tolerance is becoming a more and more important challenge in case of crop plants, notably in wheat in Europe, not only in the Mediterranean area, but in central Europe too. The breeding process includes the characterization of the basic breeding material in regard to performance under well-watered and drought stressed conditions. For our experiments we set up a mobile automatic rain shelter (MARS) system in the breeding nursery and a complex stress diagnostic system (CSDS) in greenhouse tests of the Cereal Research Non-Profit Limited Company, where we could analyze the responses of different wheat materials to drought stress. Wheat plants were grown under ideal water regime in parallel experiments using sprinkler irrigation and shadowing by MARS. In greenhouse the tested wheat materials were grown under optimal (watering to 60% of the 100% soil water capacity) and suboptimal stress (watering to 20%) conditions. The effect of water withholding on plant growing was registered by a digital imaging system in CSDS and traditional way under MARS. After harvesting, plant heights, spike lengths, grain numbers, total grain weights and other agronomical parameters were measured and values of well-watered and stressed plants were compared.
  • Authors:
    • Pepo, P.
  • Source: 45th Croatian & 5th International Symposium on Agriculture
  • Year: 2010
  • Summary: In non-irrigated treatment the maximum yields of winter wheat were 5590 kg ha -1 in biculture (maize-wheat) and 7279 kg ha-1 in triculture (peas-wheat-maize) in 2007 year characterized by water-deficit stress. In 2008 (optimum rain amount and distribution) the maximum yields were 7065 kg ha -1 (biculture) and 8112 kg ha -1 (triculture) in non irrigated conditions. The fertilization surpluses of wheat were 2853-3698 kg ha -1 (non-irrigated) and 3164-5505 kg ha -1 (irrigated) in a dry cropyear (2007) and 884-4050 kg ha -1 (non-irrigated) and 524-3990 kg ha -1 (irrigated) in an optimum cropyear (2008). The optimum fertilizer doses varied N150-200+PK in biculture and N50-150+PK in triculture depending on cropyear and irrigation. The optimalization of agrotechnical elements provides 7,8-8,5 t ha -1 yields in dry cropyear and 7,1-8,1 t ha -1 yields of wheat in good cropyear, respectively. Our scientific results proved that in water stress cropyear (2007) the maximum yields of maize were 4316 kg ha -1 (monoculture), 7706 kg ha -1 (biculture), 7998 kg ha -1 (triculture) in non irrigated circumstances and 8586 kg ha -1, 10 970 kg ha -1, 10 679 kg ha -1 in irrigated treatment, respectively. In dry cropyear (2007) the yield-surpluses of irrigation were 4270 kg ha -1 (mono), 3264 kg ha -1 (bi), 2681 kg ha -1 (tri), respectively. In optimum water supply cropyear (2008) the maximum yields of maize were 13 729-13 787 (mono), 14 137-14 152 kg ha -1 (bi), 13 987-14 180 kg ha -1 (tri) so there was no crop-rotation effect. We obtained 8,6-11,0 t ha -1 maximum yields of maize in water stress cropyear and 13,7-14,2 t ha -1 in optimum cropyear on chernozem soil with using appropriate agrotechnical elements.
  • Authors:
    • Adamczewski, K.
    • Kaczmarek, S.
    • Matysiak, K.
  • Source: Acta Scientiarum Polonorum - Agricultura
  • Volume: 9
  • Issue: 4
  • Year: 2010
  • Summary: The aim of this study was to compare the herbicidal efficiency of mixture florasulam+2,4-D (Mustang 306 SE) in spring wheat cultivar Bryza, spring barley cultivar Antek and oat cultivar Cwa sown in monocrops and two-species mixtures. Field experiments were carried out in 2005-2007 at the Experimental Station in Winna Gora (5212′N; 1727′E), owned by the Institute of Plant Protection - National Research Institute in Poznan. Herbicyd Mustang 306 SE was applied in a dose of 0.5 dm 3.ha -1 at 3-5 leaf stage of cereals using the knapsack sprayer Gloria. The analysis of weed infestation of cereal stand was made with the quantitative-weighing method twice in the growing period (3-4 weeks after the application and 7-8 weeks after the application). Efficiency of herbicide action in mixtures was compared with its effectiveness in monocrops of individual species. From the analyses made it follows that of the cereal mixtures, the barley-oat mixture was infested in the least degree, and the wheat-oat mixture in the most degree. Strongest effect of cultivation in mixtures on reduction of weed infestation was noticeable on the control treatments, where the herbicide was not applied, whereas the cereal cultivation system (pure or mixed sowing) not always differentiated the herbicide efficiency. Cereal grain yields in mixtures after the application of mixture florasulam+2,4-D were significantly higher than yields of at least one of the component, and yields of mixtures harvested from the control treatments exceeded grain yields of both cereal species in monocrops.