• Authors:
    • Hardie,Marcus
    • Clothier,Brent
    • Bound,Sally
    • Oliver,Garth
    • Close,Dugald
  • Source: Plant and Soil
  • Volume: 376
  • Issue: 1-2
  • Year: 2014
  • Summary: This study aims to (i) determine the effects of incorporating 47 Mg ha(-1) acacia green waste biochar on soil physical properties and water relations, and (ii) to explore the different mechanisms by which biochar influences soil porosity. The pore size distribution of the biochar was determined by scanning electron microscope and mercury porosimetry. Soil physical properties and water relations were determined by in situ tension infiltrometers, desorption and evaporative flux on intact cores, pressure chamber analysis at -1,500 kPa, and wet aggregate sieving. Thirty months after incorporation, biochar application had no significant effect on soil moisture content, drainable porosity between -1.0 and -10 kPa, field capacity, plant available water capacity, the van Genuchten soil water retention parameters, aggregate stability, nor the permanent wilting point. However, the biochar-amended soil had significantly higher near-saturated hydraulic conductivity, soil water content at -0.1 kPa, and significantly lower bulk density than the unamended control. Differences were attributed to the formation of large macropores (> 1,200 mu m) resulting from greater earthworm burrowing in the biochar-amended soil. We found no evidence to suggest application of biochar influenced soil porosity by either direct pore contribution, creation of accommodation pores, or improved aggregate stability.
  • Authors:
    • Smart, D. R.
    • Fanton-Borges, A. C.
    • Alsina, M. M.
  • Source: Ecosphere
  • Volume: 4
  • Issue: 1
  • Year: 2013
  • Summary: Nitrogen fertilizer applied to soil is the primary source of the greenhouse gas (GHG) nitrous oxide (N2O). The assessment of N2O emissions, or net fluxes of the GHG methane (CH4), are lacking for upland, arid agricultural ecosystems worldwide. In California, where rates of application for nitrogen (N) can exceed 300 kg per hectare for N-intensive fruit and nut crops (>2 million acres), liquid N fertilizers applied through microirrigation systems (fertigation) represent the predominant method of N fertilization. Little information is available for how these concentrated and spatially discrete N solution applications influence N2O emissions and net CH4 fluxes (the sum of methanogenic and methanotrophic activity). In this study we examined soil N2O-N emissions and net CH4 fluxes for drip and stationary microsprinklers, two of the most widely used fertigation emitters, in an almond orchard where 235.5 kg N/ha were applied during the season of measurement (2009-2010). We accomplished this by modeling the spatial patterns of N2O and CH4 at the scale of meters and centimeters using simple mathematical approaches. For two applications of 33.6 kg/ha and three applications of 56.1 kg/ha targeted to the phenologic stages with highest tree N demand, the spatial patterns of N2O fluxes were similar to the emitter water distribution pattern and independent of temperature and fertilizer N form applied. Net CH4 fluxes were extremely low and there was no discernible spatial pattern, but areas kept dry (driveways between tree rows) generally consumed CH4 while it was produced in the microirrigation wet-up area. The N2O-N emissions for fertigation events at the scale of days, and over a season, were significantly higher from the drip irrigated orchard (1.6 +/- 0.7 kg N2O-N ha(-1) yr(-1)) than a microsprinkler irrigated orchard (0.6 +/- 0.3 kg N2O-N ha(-1) yr(-1)). N2O emissions and net CH4 fluxes were only significantly correlated with soil water filled pore space and not with mineral-N. The correlation was much better for N2O emissions. Our results greatly improve our ability to scale N2O production to the orchard level, and provide growers with a tool for lowering almond orchard carbon and nitrogen footprints.
  • Authors:
    • Jair Andrade, H.
    • Alvarado, J.
    • Segura, M.
  • Source: Revista Colombia Forestal
  • Volume: 16
  • Issue: 1
  • Year: 2013
  • Summary: The increase in greenhouse gas emissions from anthropogenic sources has resulted in climate change, which affects all living beings. Coffee (Coffea arabica L.) plantations, in monoculture or together with timber species such as salmwood (Cordia alliodora), mitigate climate change due to fixation of atmospheric CO 2 that is deposited in biomass and soils. This study was carried out in the municipality of Libano, Tolima, Colombia with the objective of defining which of the following coffee production systems store more soil organic carbon (SOC): (1) monoculture, (2) agroforestry systems (AFS) with salmwood, and (3) AFS with plantain. Farms with those systems that are the most dominant in the study zone were selected. From each system, five repetitions were identified to be analyzed with a completely randomized design. In each plot or repetition, five samples for bulk density (BD) using the cylinder method and a composite sample for concentration of SOC were taken and analyzed using the Walkley and Black approach. The systems of production did not significantly (p >0.05) affect either the BD or the concentration of SOC. However, AFS with plantain tended to have less BD than monoculture and AFS with salmwood (0.830.03 vs 0.880.03 vs 0.920.04 g.cm -3, respectively). These systems of production stored between 50 and 54 t.ha -1 of SOC in the top 30 cm, which indicates their capacity for climate change mitigation.
  • Authors:
    • Zhou, D.
    • Wang, J.
    • Chen, Z.. L.
    • Bi, C. J.
  • Source: Pedosphere
  • Volume: 23
  • Issue: 2
  • Year: 2013
  • Summary: Soil health assessment is an important step toward understanding the potential effects of agricultural practices on crop yield, quality and human health. The objectives of this study were to select a minimum data set for soil health evaluation from the physical, chemical and biological properties and environmental pollution characteristics of agricultural soil and to develop a soil health diagnosis model for determining the soil health status under different planting patterns and soil types in Chongming Island of Shanghai, China. The results showed that the majority of the farmland soils in Chongming Island were in poor soil health condition, accounting for 48.9% of the survey samples, followed by the medium healthy soil, accounting for 32.2% of the survey samples and mainly distributed in the central and mid-eastern regions of the island. The indicators of pH, total organic carbon, microbial biomass carbon and Cd exerted less influence on soil health, while the soil salinization and nitrate accumulation under a greenhouse cropping pattern and phosphate fertilizer shortage in the paddy field had limited the development of soil health. Dichlorodiphenyltrichloroethanes, hexachlorocyclohexanes and Hg contributed less to soil health index (SHI) and showed no significant difference among paddy field, greenhouse and open-air vegetable/watermelon fields. The difference of the SHI of the three soil types was significant at P = 0.05. The paddy soil had the highest SHI values, followed by the gray alluvial soil, and the coastal saline soil was in a poor soil health condition, indicating a need to plant some salt-tolerant crops to effectively improve soil quality.
  • Authors:
    • Yilmaz, G.
    • Bilgili, A. V.
    • Ikinci, A.
  • Source: Turkish Journal of Agriculture & Forestry
  • Volume: 37
  • Issue: 6
  • Year: 2013
  • Summary: Broad interest in reducing greenhouse gas emissions requires a better understanding of controls on carbon dioxide (CO2) release under different agricultural management practices. The objective of this study was to investigate and model seasonal variation of soil CO2 emissions from an apple orchard field (Malus domestica L. 'Starkrimson'). Soil CO2 emissions from an apple orchard managed with common practices were measured weekly over a 3-year period (May 2008 to May 2011) from both under the crowns of trees (CO2-UC) and between rows (CO2-BR) using a soda lime technique and were modeled using available environmental data. The study area is located in the Harran Plain of southeastern Turkey and has a semiarid climate. The weekly soil CO2 emissions ranged from 87.8 to 1428 kg week(-1) ha(-1), from 74.6 to 835 kg week(-1) ha(-1), and from 88.6 to 1087 kg week(-1) ha(-1) for CO2-UC, CO2-BR, and the average of both (CO2-AVG), respectively, and showed a pronounced seasonal pattern with the lowest emissions in winter (January and February) and the highest emissions during the growing season (April to December). Relative to 2008 emissions, 2009 CO2 emissions increased by approximately 75%, and 2010 emissions increased by approximately 88%. Comparison of 3 models (multiple linear regression, principal component regression, and multivariate adaptive regression splines) showed that multivariate adaptive regression splines provided the best performance in modeling soil CO2 emissions, explaining overall variation of 64%, 56%, 76%, and 53% in CO2-AVG for the first, second, third, and all three 3 periods, respectively. In conclusion, overall findings showed that soil CO2 emissions could be modeled by available environmental data such as air and soil temperature.
  • Authors:
    • Blanke, M. M.
  • Source: Acta Horticulturae International Society for Horticultural Science
  • Issue: 998
  • Year: 2013
  • Summary: Thinning is a prerequisite in worldwide fruit production. The question arose as to its contribution to the carbon footprint in different production schemes. Carbon footprinting of thinning in fruit orchards is based on fossil fuel consumption, converted into greenhouse gas emission (GHG) and expressed as CO 2 equivalents, which comprises carbon dioxide (CO 2; factor 1), methane (CH 4; factor 25) and nitrous oxides (N 2O; factor 298), according to PAS 2050: Oct 2011 and PAS 2050-1 (hort). Flower thinning with ATS foliar nitrogen fertiliser emitted 25-37 kg CO 2e/ha per treatment (without associated N 2O emissions), while fruitlet thinning with 6-BA emitted ca. 13 kg CO 2e/ha, Brevis 18.5 (single application) or 34 (double application) kg CO 2e/ha and lime sulfur in organic orchards 27-42 kg CO 2e/ha. Mechanical thinning with the Bonner machine at 6 km/h at 360 rpm produced 27.9 kg CO 2e/ha emissions, while manual fruitlet thinning after June drop had a carbon footprint of only 3.1 kg CO 2e/ha, since manual labour does not utilize fossil fuel.
  • Authors:
    • Bonari, E.
    • Massai, R.
    • Remorini, D.
    • Galli, M.
    • Di Bene, C.
    • Bosco, S.
  • Source: The International Journal of Life Cycle Assessment
  • Volume: 18
  • Issue: 5
  • Year: 2013
  • Summary: Concerns about global warming led to the calculation of the carbon footprint (CF) left by human activities. The agricultural sector is a significant source of greenhouse gas (GHG) emissions, though cropland soils can also act as sinks. So far, most LCA studies on agricultural products have not considered changes in soil organic matter (SOM). This paper aimed to: (1) integrate the H,nin-Dupuis SOM model into the CF study and (2) outline the impacts of different vineyard soil management scenarios on the overall CF. A representative wine chain in the Maremma Rural District, Tuscany (Italy), made up of a cooperative winery and nine of its associated farms, was selected to investigate the production of a non-aged, high-quality red wine. The system boundary was established from vineyard planting to waste management after use. The functional unit (FU) chosen for this study was a 0.75-L bottle of wine, and all data refer to the year 2009. The SOM balance, based on H,nin-Dupuis' equation, was integrated and run using GaBi4 software. A sensitivity analysis was performed, and four scenarios were developed to assess the impact of vineyard soil management types with decreasing levels of organic matter inputs. SOM accounting reduced the overall CF of one wine bottle from 0.663 to 0.531 kg CO2-eq/FU. The vineyard planting sub-phase produced a loss of SOM while, in the pre-production and production sub-phases, the loss/accumulation of SOM was related to the soil management practices. On average, soil management in the production sub-phase led to a net accumulation of SOM, and the overall vineyard phase was a sink of CO2. Residue incorporation and grassing were identified as the main factors affecting changes in SOM in vineyard soils. Our results showed that incorporating SOM accounting into the wine chain's CF analysis changed the vineyard phase from a GHG source to a modest net GHG sink. These results highlighted the need to include soil C dynamics in the CF of the agricultural product. Here, the SOM balance method proposed was sensitive to changes in management practices and was site specific. Moreover, we were also able to define a minimum data set for SOM accounting. The EU recognises soil carbon sequestration as one of the major European strategies for mitigation. However, specific measures have yet to be included in the CAP 2020. It would be desirable to include soil in the new ISO 14067-Carbon Footprint of Products.
  • Authors:
    • Gonzalez, A.
    • Tapasco, J.
    • Graefe, S.
  • Source: Fruits
  • Volume: 68
  • Issue: 4
  • Year: 2013
  • Summary: Introduction. The cultivation of high-value fruit species is a profitable agricultural activity in many tropical countries; however, intensive fruit cultivation may depend on high amounts of external inputs. The objective of our study was to quantify and compare the resource use during the cultivation of eight tropical fruit species (Rubus glaucus, Solanum quitoense, Passiflora edulis, Cyphomandra betacea, Physalis peruviana, Ananas comosus, Persea americana and Mangifera indica) commonly cultivated in Colombia. It further aimed to identify greenhouse gas (GHG) emissions in the selected production systems and to highlight the potential to contribute to climate change mitigation efforts. Materials and methods. The analysis was based on data from agricultural databases and applied a life-cycle assessment with energy use and GHG emissions as impact categories. Furthermore, economic indicators were taken into account with the aim of integrating the environmental and economic goals of production systems. Results and discussion. Among the eight fruit species studied, mango (Mangifera indica) was found to have the lowest and tree tomato (Cyphomandra betacea) the highest emission profile. The variability in resource use among growers of the same species was high, indicating the need to improve management abilities at the farm level. Mineral fertilizer production was the highest contributor to GHG emissions. GHG- and energy-efficient management alternatives would have a high potential to reduce the carbon footprint of fruit cultivation.
  • Authors:
    • Chatterton, J.
    • Graves, A.
    • Kulak, M.
  • Source: Landscape and Urban Planning
  • Volume: 111
  • Issue: March
  • Year: 2013
  • Summary: The production and supply of food currently accounts for 20-30% of greenhouse gas (GHG) emissions in the UK and the government and nongovernmental organisations are seeking to reduce these environmental burdens. Local authorities all over UK establish community farms with the aim to produce more sustainable food for citizens. This study used environmental Life Cycle Assessment (LCA) to quantify the potential savings of food-related GHG emissions that may be achieved with the establishment of an urban community farm, based on a case study recently found in the London Borough of Sutton. The work identified elements of the farm design that require the greatest attention to maximise these savings. The greatest reductions can be achieved by selecting the right crops: (i) providing the highest yields in local conditions and (ii) usually produced in energy-intensive greenhouses or air-freighted to UK from outside Europe. Implications from further development of the farm on the local, unused land were examined, taking into account market requirements. This showed that land used on an urban fringe for food production could potentially reduce greenhouse gas emissions in Sutton by up to 34 t CO(2)e ha(-1) a(-1). Although the percentage of this reduction in total diet emissions is relatively low, the result exceeds carbon sequestration rates for the conventional urban green space projects, such as parks and forests. (C) 2012 Elsevier B.V. All rights reserved.
  • Authors:
    • Ro, H.-M.
    • Lee, H.-C.
    • Kim, J.-S.
    • Choi, J.-J.
    • Lee, T.-K.
  • Source: Korean Journal of Horticultural Science & Technology
  • Volume: 31
  • Issue: 6
  • Year: 2013
  • Summary: To report country-specific carbon and nitrogen stocks data in a pear orchard by Tier 3 approach of 2006 IPCC guidelines for national greenhouse gas inventories, an experimental pear orchard field of the Pear Research Station, National Institute of Horticultural & Herbal Science, Rural Development Administration, Naju, Korea (35 01'27.70 N, 126 44'53.50"E, 6 m altitude), where 15-year-old `Niitaka' pear (Pyrus pyrifolia Nakai cv. Niitaka) trees were planted at a 5.0 m x 3.0 m spacing on a Tatura trellis system, was chosen to assess the total amount of carbon and nitrogen stocks stored in the trees and orchard soil profiles. At the sampling time (August 2012), three trees were uprooted, and separated into six fractions: trunk, main branches, lateral branches (including shoots), leaves, fruits, and roots. Soil samples were collected from 0 to 0.6 m depth at 0.1 m intervals at 0.5 m from the trunk. Dry mass per tree was 4.7 kg for trunk, 13.3 kg for main branches, 13.9 kg for lateral branches, 3.7 kg for leaves, 6.7 kg for fruits, and 14.1 kg for roots. Amounts of C and N per tree were respectively 2.3 and 0.02 kg for trunk, 6.4 and 0.07 kg for main branches, 6.4 and 0.09 kg for lateral branches, 6.5 and 0.07 kg for roots, 1.7 and 0.07 kg for leaves, and 3.2 and 0.03 kg for fruits. Carbon and nitrogen stocks stored between the soil surface and a depth of 60 cm were 138.29 and 13.31 Mg.ha(-1), respectively, while those contained in pear trees were 17.66 and 0.23 Mg ha' based on a tree density of 667 trees-ha-1.0verall, carbon and nitrogen stocks per hectare stored in a pear orchard were 155.95 and 13.54 Mg, respectively.