• Authors:
    • Simmons, A.
    • Muir, S.
    • Brock, P.
  • Source: Conference Paper
  • Volume: 3
  • Year: 2014
  • Summary: Australian agricultural industries contribute approximately 14.6% of net annual national greenhouse gas (GHG) emissions, with N 2O emissions from agricultural soils the second greatest source of these emissions. Given that 25 M ha of land in Australia is cropped, the technical potential for GHG emissions reduction in Australian grain production systems is substantial. The New South Wales Department of Primary Industries (NSW DPI) has developed research capacity in Life Cycle Assessment (LCA) to assess this mitigation potential. In this paper we provide insights into the regionally-specific approach that we are taking, not only to provide credible management options at a grain grower level and ensure that detailed data are available for analysis by participants in the downstream supply chain, but also to provide data which, in an aggregated form, will underpin market access and inform national policy development. We report on initial NSW DPI studies and discuss a new project, funded by the Grains Research and Development Corporation (GRDC), to determine emissions reduction opportunities for each of Australia's agro-ecological zones. Initial studies show total emissions from wheat production in the order of 200 kg CO 2-e per tonne, with values ranging down to 140 kg CO 2-e per tonne. In one study, replacing synthetic nitrogenous fertiliser with biologically fixed N reduced emissions to 33% of prior values. The new project is particularly concerned with developing accurate foreground data by triangulating several sources of published literature (including official statistics) and conducting 'groundtruthing' through panels of regionally-based advisors to increase data specificity. The LCAs and associated mitigation strategies will be underpinned by a median and relevant distribution of values for inputs, practices and yields, with system assumptions clearly documented.
  • Authors:
    • Fisher,S.
    • Karunanithi,A.
  • Source: Proceedings of the 9th International Conference on Life Cycle Assessment in the Agri-Food Sector
  • Year: 2014
  • Summary: Local policy makers typically do not have useful, quantitative metrics to compare environmental costs and benefits of urban vegetable production versus the large-scale commercial production in the typical grocery store supply chain. While urban agriculture has been championed as a way to address social issues such as food access and nutrition, we know relatively little about net environmental benefits, if any. The study combines a comparative life cycle assessment of vegetables with effects of direct and indirect land use change resulting from the urban vegetable production. This paper presents a methodology and selected results of scenarios of land use change due to urban vegetable production address resource use, greenhouse gas emissions, employment, and soil organic carbon. Surprisingly, urban vegetable production is not categorically favorable for each metric; several key parameters can shift the balance in favor or out of favor for either growing format, and these parameters are distinctly bottom-up.
  • Authors:
    • Putri,E. A.
    • Koido,K.
    • Dowaki,K.
  • Source: Proceedings of the 9th International Conference on Life Cycle Assessment in the Agri-Food Sector
  • Year: 2014
  • Summary: Climate change is mainly linked to greenhouse gas (GHG) emissions in which the agricultural sector occupies 14% of total emissions. In this paper, the questionnaires were implemented to investigate the effects of green bean quality including eco-burden factor and price on consumer buying decision. Also, on the estimation of eco-burden, LCA methodology was considered, and the carbon footprint of green bean in the supply chain process in Indonesia was expressed. The results showed that the total emissions (CFP) of green bean were between 4.92 and 7.38 kg-CO 2eq/kg green bean by varying farmers, and they became larger than that of Japan case (1.11 kg-CO 2eq/kg green bean). In addition, through our questionnaires on basis of the quality and price of green bean, we confirmed that the factor of quality is more significant for consumer buying decision.
  • Authors:
    • Vazquez-Rowe,I.
    • Villanueva-Rey,P.
    • Otero,M.
    • Moreira,M. T.
    • Feijoo,G.
  • Source: Proceedings of the 9th International Conference on Life Cycle Assessment in the Agri-Food Sector (LCA Food 2014)
  • Year: 2014
  • Summary: Land use changes (LUCs) are an important source of environmental changes in production systems, especially in the agricultural sector, where LUCs have been found to be a relevant factor to take into consideration when analyzing greenhouse gas (GHG) emissions. The viticulture subsector, as part of a broader agricultural sector, is not alien to the problematic of GHG emissions and climate change. Spain, as one of the main producers of wine worldwide, but also due to the important legislative and productive changes that have occurred ever since it joined the European Union, plays an important role in the analysis of how LUCs linked to the viticulture sector have effects on the environment. Therefore, in the current study we examined the LUCs that have occurred in the Ribeiro appellation in NW Spain between 1989 and 2009. For this, GIS was used to map the gradual dynamic changes on an annual basis of the areas used for wine production. Thereafter, the different land uses that substituted or were substituted by vineyards were identified in order to calculate the carbon storage and carbon emission dynamics based on the IPCC guidelines. Finally, operational activities linked to viticulture, including changes in technology over time, were added to the model in order to obtain a broad picture of entire impact of viticulture in terms of GHG emissions. The results present an interesting pattern, with GHG emissions linked to LUCs steadily decreasing in the timeframe analyzed. Similarly, the improvement of machinery, the reduction on fossil dependency in the Spanish electricity mix and the stricter use of specific standards for the use of plant protection agents also contributed to a gradual decrease in GHG emissions per functional unit (i.e. 1 ha of cultivated vineyards). These results are aimed at providing the appellation and other appellations throughout with environmentally relevant information regarding how different factors influencing their change through time can be analyzed to give support in policy making and decision making at a business level.
  • Authors:
    • Zwickel, T.
    • Van Vuuren, D. P.
    • Winkler, H.
    • Riahi, K.
    • O'Neill, B. C.
    • Mathur, R.
    • Kriegler, E.
    • Edmonds, J.
    • Carter, T. R.
    • Arnell, N. W.
    • Kram, T.
    • Hallegatte, S.
    • Ebi, K. L.
  • Source: Research Article
  • Volume: 122
  • Issue: 3
  • Year: 2014
  • Summary: The scientific community is developing new global, regional, and sectoral scenarios to facilitate interdisciplinary research and assessment to explore the range of possible future climates and related physical changes that could pose risks to human and natural systems; how these changes could interact with social, economic, and environmental development pathways; the degree to which mitigation and adaptation policies can avoid and reduce risks; the costs and benefits of various policy mixes; and the relationship of future climate change adaptation and mitigation policy responses with sustainable development. This paper provides the background to and process of developing the conceptual framework for these scenarios, as described in the three subsequent papers in this Special Issue (Van Vuuren et al., 2013; O'Neill et al., 2013; Kriegler et al., Submitted for publication in this special issue). The paper also discusses research needs to further develop, apply, and revise this framework in an iterative and open-ended process. A key goal of the framework design and its future development is to facilitate the collaboration of climate change researchers from a broad range of perspectives and disciplines to develop policy- and decision-relevant scenarios and explore the challenges and opportunities human and natural systems could face with additional climate change.
  • Authors:
    • Vuuren, D. P.
    • Tavoni, M.
    • Rose, S. K.
    • Richels, R.
    • Riahi, K.
    • Luderer, G.
    • Fawcett, A.
    • Edmonds, J.
    • Clarke, L.
    • Krey, V.
    • Blanford, G. J.
    • Weyant, J. P.
    • Kriegler, E.
  • Source: Web Of Knowledge
  • Volume: 123
  • Issue: 3-4
  • Year: 2014
  • Summary: This article presents the synthesis of results from the Stanford Energy Modeling Forum Study 27, an inter-comparison of 18 energy-economy and integrated assessment models. The study investigated the importance of individual mitigation options such as energy intensity improvements, carbon capture and storage (CCS), nuclear power, solar and wind power and bioenergy for climate mitigation. Limiting the atmospheric greenhouse gas concentration to 450 or 550 ppm CO2 equivalent by 2100 would require a decarbonization of the global energy system in the 21(st) century. Robust characteristics of the energy transformation are increased energy intensity improvements and the electrification of energy end use coupled with a fast decarbonization of the electricity sector. Non-electric energy end use is hardest to decarbonize, particularly in the transport sector. Technology is a key element of climate mitigation. Versatile technologies such as CCS and bioenergy are found to be most important, due in part to their combined ability to produce negative emissions. The importance of individual low-carbon electricity technologies is more limited due to the many alternatives in the sector. The scale of the energy transformation is larger for the 450 ppm than for the 550 ppm CO(2)e target. As a result, the achievability and the costs of the 450 ppm target are more sensitive to variations in technology availability.
  • Authors:
    • Soinne,Helena
    • Hovi,Jarkko
    • Tammeorg,Priit
    • Turtola,Eila
  • Source: Geoderma
  • Volume: 219
  • Year: 2014
  • Summary: Soil structure is one of the key properties affecting the productivity of soils and the environmental side effects of agricultural soils. Poor surface soil structure increases the risk of soil erosion by water and eroded clay-sized particles can carry adsorbed phosphorus (P) to the surface waters, thus inducing eutrophication of receiving waterways. Management practices, e.g. reduced tillage, used to reduce erosion can lead to enrichment of P in the uppermost soil layers, which leads to elevated risk for dissolved P loss in the runoff water. In this study, we aimed to identify whether biochar (BC) could be used to reduce clay soil erosion by improving aggregate stability. Moreover, we tested whether the BC addition would change the P sorption affinity of the soil and help to reduce the loss of dissolved P. One sandy and two clayey soils were amended with BC (0,15 and 30 t ha(-1)) and after a 3week incubation, a wet-sieving method was used to measure the release of colloidal particles and the stability of aggregates. The sorption of P onto soil surfaces was estimated with a Q/I (quantity/intensity) plot technique. The BC used here had a very low P sorption affinity and the BC addition did not increase the sorption of P in incubated soils. However, for the two clayey soils, the BC additions increased aggregate stability and reduced detachment of colloidal material. The BC thus induced changes in soil properties that could be beneficial for erosion control and thereby aid in reducing particulate P losses from agricultural fields. (c) 2014 Elsevier B.V. All rights reserved.
  • Authors:
    • Alvaro-Fuentes,J.
    • Plaza-Bonilla,D.
    • Arrue,J. L.
    • Lampurlanes,J.
    • Cantero-Martinez,C.
  • Source: Plant and Soil
  • Volume: 376
  • Issue: 1-2
  • Year: 2014
  • Summary: The duration of soil organic carbon (SOC) sequestration in agricultural soils varies according to soil management, land-use history and soil and climate conditions. Despite several experiments have reported SOC sequestration with the adoption of no-tillage (NT) in Mediterranean dryland agroecosystems scarce information exists about the duration and magnitude of the sequestration process. For this reason, 20 years ago we established in northeast Spain a NT chronosequence experiment to evaluate SOC sequestration duration under Mediterranean dryland conditions. In July 2010 we sampled five chronosequence phases with different years under NT (i.e., 1, 4, 11, and 20 years) and a continuous conventional tillage (CT) field, in which management prevailed unchanged during decades. Soil samples were taken at four depths: 0-5, 5-10, 10-20 and 20-30 cm. The SOC stocks were calculated from the SOC concentration and soil bulk density. Furthermore, we applied the Century ecosystem model to the different stages of the chronosequence to better understand the factors controlling SOC sequestration with NT adoption. Differences in SOC stocks were only found in the upper 5 cm soil layer in which 4, 11 and 20 years under NT showed greater SOC stocks compared with 1 year under NT and the CT phase. Despite no significant differences were found in the total SOC stock (0-30 cm soil layer) there was a noteworthy difference of 5.7 Mg ha(-1) between the phase with the longest NT duration and the phase under conventional tillage. The maximum annual SOC sequestration occurred after 5 years of NT adoption with almost 50% change in the annual rate of SOC sequestration. NT sequestered SOC over the 20 years following the change in management. However, more than 75% of the total SOC sequestered was gained during the first 11 years after NT adoption. The Century model predicted reasonably well SOC stocks over the NT chronosequence. In Mediterranean agroecosystems, despite the continuous use of NT has limited capacity for SOC sequestration, other environmental and agronomic benefits associated to this technique may justify the maintenance of NT over the long-term.
  • Authors:
    • Thompson, A.
    • Chadwick, O. A.
    • Kramer, M. G.
    • Buettner, S. W.
  • Source: Journal
  • Volume: 221
  • Year: 2014
  • Summary: The transport of organic carbon (C) to deep mineral horizons in soils can lead to long-term C stabilization. In basaltic soils, C associations with short-range-ordered (SRO) minerals often lead to colloid-sized aggregates that can be dispersed and mobilized by changes in soil solution chemistry. In the montane forest region of Hawaii, basaltic soils are exposed to high rainfall and anoxic conditions that facilitate ferric (Fe-III) (oxyhydr)oxide reduction. We explored the potential of iron (Fe)-reducing conditions to mobilize C by exposing the surface mineral horizons of three soils from the Island of Hawai'i (aged 03, 20, and 350 ky) to 21 days of anoxic incubation in 1:10 soil slurries. Mobilized C was quantified by fractionating the slurries into three particle-size classes (<430 nm,<60 nm,<23 nm approximate to 10 kDa). In all three soils, we found Fe reduction (maximum Fe2+ (aq) concentration approximate to 17.7 +/- 1.9 mmol kg(-1) soil) resulted in similar to 500% and similar to 700% increase of C in the 23-430 nm, and <23 nm size fractions, respectively. In addition, Fe reduction increased solution ionic strength by 127 mu S cm(-1) and generated hydroxyl ions sufficient to increase the slurry pH by one unit. We compared this to C mobilized from the slurries during a 2-h oxic incubation across a similar range of pH and ionic strength and found smaller amounts of dissolved (<23 nm) and colloidal (23-430 nm) C were mobilized relative to the Fe reduction treatments (p < 0.05). In particular, C associated with the largest particles (60-430 nm) was dispersed almost exclusively during the Fe reduction experiments, suggesting that it had been bound to Feoxide phases. Our experiments suggest that colloidal dispersion during Fe-reducing conditions mobilizes high concentrations of C, which may explain how C migrates to deep mineral horizons in redox dynamic soils. (C) 2014 Elsevier B.V. All rights reserved.
  • Authors:
    • Zurek, A.
    • Pecio, A.
    • Niedzwiecki, J.
    • Debaene, G.
  • Source: Research Article
  • Volume: 214
  • Issue: 214–215
  • Year: 2014
  • Summary: Precision agriculture (PA) is a management method that measures and manages within-field variability. Previously, PA has required expansive and time consuming measurement of soil physical and chemical properties. In this paper we use a new and more rapid method of data collection based on Visible and Near-Infrared Spectroscopy (VIS-NIRS) in the 400-2200 nm spectral range to predict soil organic carbon (SOC), plant available [Mg, P, K], pH and texture at the farm scale. The experimental work was done at the experimental Station at Baborowko (52.583778 degrees N, 16.647353 degrees E) in Poland. The focus of the paper was to look at the effect of the number of samples on the calibration. Different calibration schemes using PLS regression with calibration datasets of different sizes were applied. The best predictions were obtained using K-means clustering for calibration sample selection. Using this scheme and 79 calibration samples, satisfactory results were obtained predicting SOC (r(2) = 0.63; RMSEP = 0.13%) and soil texture (e.g. clay, r(2) = 0.71; RMSEP = 0.36%). The use of the entire dataset did not improve significantly the prediction ability (r(2) = 0.72; RMSEP = 0.12% for SOC and r(2) = 0.73; RMSEP = 032% for clay). Reasonable results were obtained for available Mg content (r(2) = 0.53; RMSEP = 1.54 mg.100 g(-1)) and pH (r(2) -= 0.52; RMSEP = 034 pH unit). Available [P, K] gave unsatisfactory results (r(2) < 0.5 for both; RMSEP 6.27 and 331 mg.100 g(-1) respectively). The maps (SOC and pH) generated with the K-means clustering scheme were compared with those obtained with reference data. The results show that the VIS-NIRS method is suitable to adequately predict SOC and texture using 1.5 samples per ha (79 samples). The method can also be useful as a rough screening for pH and available Mg thereby significantly reducing the cost of mapping. (C) 2013 Elsevier B.V. All rights reserved.