• Authors:
    • Mu,J. E.
    • Wein,A. M.
    • McCarl,B. A.
  • Source: Mitigation and Adaptation Strategies for Global Change
  • Volume: 20
  • Issue: 7
  • Year: 2015
  • Summary: We examine the effects of crop management adaptation and climate mitigation strategies on land use and land management, plus on related environmental and economic outcomes. We find that crop management adaptation (e.g. crop mix, new species) increases Greenhouse gas (GHG) emissions by 1.7 % under a more severe climate projection while a carbon price reduces total forest and agriculture GHG annual flux by 15 % and 9 %, respectively. This shows that trade-offs are likely between mitigation and adaptation. Climate change coupled with crop management adaptation has small and mostly negative effects on welfare; mitigation, which is implemented as a carbon price starting at $15 per metric ton carbon dioxide (CO2) equivalent with a 5 % annual increase rate, bolsters welfare carbon payments. When both crop management adaptation and carbon price are implemented the effects of the latter dominates. © 2013, Springer Science+Business Media Dordrecht.
  • Authors:
    • Nugroho,P. A.
    • Shimizu,M.
    • Nakamato,H.
    • Nagatake,A.
    • Suwardi,S.
    • Sudadi,U.
    • Hatano,R.
  • Source: Plant, Soil and Environment
  • Volume: 61
  • Issue: 9
  • Year: 2015
  • Summary: The effect of mineral fertilizer (F) and mineral combined with organic fertilizer (MF) on N 2O flux in grassland and cornfield was investigated for one year in Southern Hokkaido, Japan. Annual N 2O flux was higher in grassland than in cornfield, and it was higher in MF plot (14.9 kg N/ha/period) than in F plot (11.1 kg N/ha/period) in grassland. However, in cornfield, the annual N 2O flux was equal between both plots (5.6 kg N/ha/period). These results clarified that high nitrogen application was not always responsible for the high soil N 2O flux. N 2O flux was significantly correlated with air, soil temperature and water-filled pore space. More than 80% of the annual N 2O flux occurred before freezing and less than 4% during melting period. Denitrification was the main process of N 2O flux during study, it was evidenced by the distribution of N 2O and NO ratio which is from 1 to 1000. The denitrification activity (DEA) potentially increased in grassland soil in the beginning and the end of winter season when NO 3-N was abundant; on the other hand the abundance of carbon potentially increased DEA in cornfield soil.
  • Authors:
    • Panday,D.
    • Nkongolo,N. V.
  • Source: Procedia Environmental Sciences
  • Volume: 29
  • Year: 2015
  • Summary: Knowledge of the impact of soil and crop management practices on soil processes is important in the study of greenhouse gases emissions from agricultural fields. We assessed the effect of soil air (pore space indices) and water (content, theta; and potential, Psi) on greenhouse gases emissions in corn/soybean field. The study was conducted in 2011 and 2012 on a silt loam soil at Freeman farm of Lincoln University. Soil samples were collected at four depths: 0-10, 10-20, 20-40 and 40-60 cm and they were oven dried at 105°C for 72 h for the calculation of air filled porosity (AFP), total pore space (TPS) and other soil physical properties. Pore space indices were computed using diffusivity models based on AFP and TPS. Soil samples were later saturated then brought into a pressure plate for measurements of moisture content (theta) at five different water potentials (Psi). Soil air samples for the measurements of greenhouse gases emissions were collected using static and vented chambers of 30 cm height and 20 cm diameter. The concentrations of CO2, CH4 and N2O in soil air samples were determined using a Gas Chromatograph GC-14. Results showed that pore space indices significantly correlated with greenhouse gases fluxes (p<0.05) with correlation coefficient (r) ranged from 0.27 to 0.53. More correlations were found in 2012 than 2011. Similarly, significant correlations were found between greenhouse gases and theta at Psi=0 and Psi=-0.05. Moisture content (theta) held at Psi=0 positively correlated with CO2 (r=0.49), N2O (r=0.64) and negatively correlated with CH4 (r=-0.43) at p<0.05. Soil pore space indices and soil water (content and potential) seem to control greenhouse gases emissions in this soil. Inclusion of these controlling factors in models will certainly improve our understanding of the dynamics of greenhouse gases fluxes from soil.
  • Authors:
    • Schmer,Marty R.
    • Jin,Virginia L.
    • Wienhold,Brian J.
  • Source: Biomass and Bioenergy
  • Volume: 81
  • Year: 2015
  • Summary: Changes in direct soil organic carbon (SOC) can have a major impact on overall greenhouse gas (GHG) emissions from biofuels when using life-cycle assessment (LCA). Estimated changes in SOC, when accounted for in an LCA, are typically derived from near-surface soil depths (30 cm) could have a large positive or negative impact on overall GHG emissions from biofuels that are not always accounted for. Here, we evaluate how sub-surface SOC changes impact biofuel GHG emissions for corn (Zea mays L.) grain, corn stover, and switchgrass (Panicum virgatum L.) using the (Greenhouse Gases, Regulated Emissions, and Energy Use in the Transportation) GREET model. Biofuel GHG emissions showed as much as a 154% difference between using near-surface SOC stocks changes only or when accounting for both near- and sub-surface SOC stock changes. Differences in GHG emissions highlight the importance of accounting for sub-surface SOC changes especially in bioenergy cropping systems with potential for soil C storage to deeper soil depths. Published by Elsevier Ltd.
  • Authors:
    • Solaiman,Zakaria M.
    • Anawar,Hossain M.
  • Source: Pedosphere
  • Volume: 25
  • Issue: 5
  • Year: 2015
  • Summary: Biochar addition to soil is currently being considered as a means to sequester carbon while simultaneously improving soil health, soil fertility and agronomic benefits. The focus of this special issue is on current research on the effects of biochar application to soil for overcoming diverse soil constraints and recommending further research relating to biochar application to soil. The biochar research has progressed considerably with important key findings on agronomic benefits, carbon sequestration, greenhouse gas emissions, soil acidity, soil fertility, soil health, soil salinity, etc., but more research is required before definitive recommendations can be made to end-users regarding the effects of biochar application across a range of soils, climates and land management practices.
  • Authors:
    • Thomas,B. W.
    • Sharifi,M.
    • Whalen,J. K.
    • Chantigny,M. H.
  • Source: Soil Science Society of America Journal
  • Volume: 79
  • Issue: 5
  • Year: 2015
  • Summary: Manuring soil alters mineralizable N pools and organic matter fractions, but the magnitude is manure-type and soil-texture specific, complicating prediction of N mineralization. Our objective was to determine the responses of residual soil mineralizable N parameters to manure-type and evaluate their relationships to initial organic C and N fractions, C/N ratios, and mineral N concentrations in sandy loam and silty clay soils after three annual spring applications of manure. Manure types were liquid swine manure (LSM), liquid dairy cattle manure (LCM), or solid poultry manure (SPM), all applied at 90 kg available N ha-1 yr-1. Mineral fertilizer (NPK) and a zero-N control (CTL) were also included. Composite soil samples collected (0-to 20-cm depth) before manure application were aerobically incubated at 25°C for 48 wk. Both soils mineralized N linearly over 48 wk (r2 = 0.96-0.99) and the silty clay soil did not converge to nonlinear, first-order kinetics. Pool I (N mineralized in first 2 wk) was the only mineralizable N pool affected by manure-type, which was depleted by SPM in the sandy loam and increased by LCM in the silty clay. Salt extractable organic N was significantly correlated to Pool I in both soil textures. Only Pool I was significantly correlated with N mineralized over 48 wk in the sandy loam and silty clay soils (r = 0.92 and 0.64, respectively). Overall, readily mineralizable N (Pool I) was the most sensitive and robust indicator of mineralizable N after three annual manure applications to agricultural soils from a humid temperate region. © Soil Science Society of America, 5585 Guilford Rd., Madison WI 53711 USA. All Rights reserved.
  • Authors:
    • Bailey,Rebecca R.
    • Butts,Thomas R.
    • Lauer,Joseph G.
    • Laboski,Carrie A. M.
    • Kucharik,Christopher J.
    • Davis,Vince M.
  • Source: Weed Science
  • Volume: 63
  • Issue: 4
  • Year: 2015
  • Summary: Nitrous oxide (N2O) is a potent greenhouse gas with implication for climate change. Agriculture accounts for 10% of all greenhouse gas emissions in the United States, but 75% of the country's N2O emissions. In the absence of PRE herbicides, weeds compete with soybean for available soil moisture and inorganic N, and may reduce N2O emissions relative to a weed-free environment. However, after weeds are killed with a POST herbicide, the dead weed residues may stimulate N2O emissions by increasing soil moisture and supplying carbon and nitrogen to microbial denitrifiers. Wider soybean rows often have more weed biomass, and as a result, row width may further impact how weeds influence N2O emissions. To determine this relationship, field studies were conducted in 2013 and 2014 in Arlington, WI. A two-by-two factorial treatment structure of weed management (PRE + POST vs. POST-only) and row width (38 or 76 cm) was arranged in a randomized complete block design with four replications. N2O fluxes were measured from static gas sampling chambers at least weekly starting 2 wk after planting until mid-September, and were compared for the periods before and after weed termination using a repeated measures analysis. N2O fluxes were not influenced by the weed by width interaction or width before termination, after termination, or for the full duration of the study at P <= 0.05. Interestingly, we observed that POST-only treatments had lower fluxes on the sampling day immediately prior to POST application (P = 0.0002), but this was the only incidence where weed influenced N2O fluxes, and overall, average fluxes from PRE + POST and POST-only treatments were not different for any period of the study. Soybean yield was not influenced by width (P = 0.6018) or weed by width (P = 0.5825), but yield was 650 kg ha(-1) higher in the PRE + POST than POST-only treatments (P = 0.0007). These results indicate that herbicide management strategy does not influence N2O emissions from soybean, and the use of a PRE herbicide prevents soybean yield loss. Nomenclature: Soybean; Glycine max (L.) Merr.
  • Authors:
    • Beach,R. H.
    • Cai,Y.
    • Thomson,A.
    • Zhang,X.
    • Jones,R.
    • McCarl,B. A.
    • Crimmins,A.
    • Martinich,J.
    • Cole,J.
    • Ohrel,S.
    • Deangelo,B.
    • McFarland,J.
    • Strzepek,K.
    • Boehlert,B.
  • Source: Environmental Research Letters
  • Volume: 10
  • Issue: 9
  • Year: 2015
  • Summary: Increasing atmospheric carbon dioxide levels, higher temperatures, altered precipitation patterns, and other climate change impacts have already begun to affect US agriculture and forestry, with impacts expected to become more substantial in the future. There have been numerous studies of climate change impacts on agriculture or forestry, but relatively little research examining the long-term net impacts of a stabilization scenario relative to a case with unabated climate change. We provide an analysis of the potential benefits of global climate change mitigation for US agriculture and forestry through 2100, accounting for landowner decisions regarding land use, crop mix, and management practices. The analytic approach involves a combination of climate models, a crop process model (EPIC), a dynamic vegetation model used for forests (MC1), and an economic model of the US forestry and agricultural sector (FASOM-GHG). We find substantial impacts on productivity, commodity markets, and consumer and producer welfare for the stabilization scenario relative to unabated climate change, though the magnitude and direction of impacts vary across regions and commodities. Although there is variability in welfare impacts across climate simulations, we find positive net benefits from stabilization in all cases, with cumulative impacts ranging from $32.7 billion to $54.5 billion over the period 2015-2100. Our estimates contribute to the literature on potential benefits of GHG mitigation and can help inform policy decisions weighing alternative mitigation and adaptation actions. © 2015 IOP Publishing Ltd.
  • Authors:
    • Pikula, D.
    • Faber, A.
    • Syp, A.
  • Source: Plant Soil Environ.
  • Volume: 61
  • Issue: 10
  • Year: 2015
  • Summary: The study presents the impact of management practices on greenhouse gas emissions (GHG) and nitrogen (N) losses calculated with a denitrification-decomposition model. Two cropping systems were analysed. The first rotation (A) consisted of potato, winter wheat, spring barley and corn. The second (B) included potato, winter wheat, spring barley and clover with grasses mixture. In A1 and B1 scenarios, fluxes were estimated on the basis of mineral fertilizers input, whereas in A2 and B2 scenarios the assessment of emissions was made with regards to manure. The results indicated that the application of manure in A rotation led to the increase of nitrous oxide (N 2O) emission, N leaching, N surplus, crop yields, and the decrease of nitrogen use efficiency higher than in B rotation. Additional doses of manure in A2 scenario increased the potential of the accumulation of soil organic carbon (SOC) and global warming potential (GWP) by 157%. In B2 scenario, SOC augmented more than three-fold but GWP increased only by 10%. The N losses and GHG emissions could be minimised by controlling N application through the implementation of nutrient management plan in which N doses are defined based on the crop needs and soil quality.
  • Authors:
    • Wilkens,S.
    • Weimer,P. J.
    • Lauer,J. G.
  • Source: Agronomy Journal
  • Volume: 107
  • Issue: 6
  • Year: 2015
  • Summary: Full-season corn ( Zea mays L.) hybrids take advantage of more of the growing season than shorter-season hybrids often leading to greater grain and biomass yield. Many agronomic experiments aimed at corn stover production have been performed at forage harvest rather than later when stover is normally harvested for biofuel measurements. The objective of this research was to evaluate the influence of hybrid relative maturity (days RM) on stover ethanol production, ruminant digestibility, and biomass composition. Hybrids selected were high-yielding commercial grain hybrids grown throughout Wisconsin and ranged from 85 to 115 d RM in 10 d RM increments during 2009, and in 5 d RM increments during 2010. Hybrids were harvested at physiological maturity or after a killing frost. Overall, stover and theoretical ethanol yields increased as RM increased at a linear rate of 0.211 Mg ha -1 RM -1 and 67.1 L ha -1 RM -1. Stover nutritional and biomass composition improved as RM increased, but yield variability was greater than nutritional and biomass compositional variability. Increasing ethanol yields will likely occur by increasing stover yields rather than by altering stover composition. Therefore, until price premiums for stover composition are made available to farmers for ethanol production, the adoption of full-season or longer maturing hybrids should be implemented for increased stover and ethanol yields.