• Authors:
    • Managanvi, K.
    • Erayya
    • Makanur, B
    • Jagdish, J.
  • Source: Environment and Ecology
  • Volume: 31
  • Issue: 2
  • Year: 2013
  • Summary: The evidence for climate change is now considered to be unequivocal, and trends in atmospheric carbon dioxide (CO 2), temperature and sealevel rise are tracking the upper limit of model scenarios elaborated in the Fourth Assessment (AR4) undertaken by the International Panel on Climate Change (IPCC). Agriculture directly contributes almost 14% of total Green House Gas (GHG) emissions and indirectly accounts for a further 7% incurred by the conversion of forests to agriculture (mostly conversion to rangeland in the Amazon), currently at the rate of 7.3 million ha/year. It focuses on specific aspects of agriculture and agricultural water management that contribute to greenhouse gas emissions and offer prospects for mitigation. In addition to the impacts of cycles of wetting and drying, the concentration of inorganic and organic fertilizer on land with some form of water management means that the practice of irrigation has scope to mitigate GHG emissions. Global atmospheric temperature is predicted to rise by approximately 4°C by 2080, consistent with a doubling of atmospheric CO 2 concentration. Increased atmospheric concentrations of CO 2 enhance photosynthetic efficiency and reduce rates of respiration, offsetting the loss of production potential due to temperature rise. Early hopes for substantial CO 2 mitigation of production losses due to global warming have been restrained. A second line of reasoning is that by the time CO 2 levels have doubled, temperatures will also have risen by 4°C, negating any benefit.
  • Authors:
    • Sajjakulnukit, B.
    • Jenjariyakosoln, S.
    • Garivait, S.
  • Source: International Journal of Environmental Science and Development
  • Volume: 4
  • Issue: 2
  • Year: 2013
  • Summary: This paper presents an approach to evaluate the net energy potential of sugarcane field residues in Thailand. It was estimated that around 13,595 ktons of sugarcane field residues was burned in the field annually in the country. Assuming 100% collection efficiency, this amount could be converted to 210.46 PJ through power generation. The quantity of greenhouse gases (GHGs) including CO 2, CH 4, and N 2O emitted from open burning of sugarcane residues was compared to that released from power production using life cycle analysis methodology for the estimation. It was found that the avoided GHG emissions obtained for power generation represent 11,836 ktons CO 2 equivalent, based on the country specific emission factor of electricity production using coal as fuel of 1.09 kg CO 2/kWh. Although this enormous potential for energy production in Thailand, sugarcane field residues availability is subject to seasonal variability, which limits its capacity to serve as fuel for power generation. The total avoided GHG emissions were therefore 11,836 ktons CO 2eq and 8,285 ktons CO 2eq annually for collection efficiency of 100% and 70%, respectively. Comparatively to the national CO 2 emissions from coal power generation of 34,532 ktons CO 2eq in 2011, the avoided GHG emissions would be about 34% and 24% for collection efficiency of 100% and 70%, respectively.
  • Authors:
    • Govindaraj, M.
    • Prabukumar, G.
    • Arunachalam, P.
    • Kannan, P.
  • Source: African Journal of Agricultural Research
  • Volume: 8
  • Issue: 21
  • Year: 2013
  • Summary: Atmospheric rise of CO 2, N 2O and CH 4 over years, accelerated increase in global temperature, has led to uncertainty in monsoon rainfall and also leading to recurrence of drought, which in turn is severely affecting crop productivity and livelihood security of the farmers in Semi Arid Tropics. Agriculture contributes considerable amount of CO 2, N 2O and CH 4 emission into the atmosphere through different soil and crop management practices. Nevertheless agricultural activities contribute to global warming. The medium of crop production, soil is one of the major sinks of global warming gaseous and it helps to sequester more carbon and cut the N 2O emission by adopting smart soil and crop management techniques. Biochar is one of the viable organic amendments to combat climate change and sustain the soil health with sustainable crop production. It is an anaerobic pyrolysis product derived from organic sources and store carbon on a long term basis in the terrestrial ecosystem and also capable of reducing greenhouse gases (GHG) emission from soil to the atmosphere. Biochar application improved the soil health, increase the carbon capture and storage, reduce the GHG emission and enhance the crop yield with sustained soil health, which enables to meet out the food grain needs of the ever growing population.
  • Authors:
    • Navichoc, D.
    • Soto, M.
    • Rivera, L.
    • Killian, B.
  • Source: Journal of Agricultural Science and Technology, B
  • Volume: 3
  • Issue: 3
  • Year: 2013
  • Summary: The issue of carbon emissions has been on the corporate sustainability agenda for some years. For those working in agricultural supply chains, the challenges remain significant, given the diverse direct and indirect emissions occurring throughout the value chain. This study determines the carbon footprint of the supply chain of Costa Rican coffee exported to Europe, using best practice methodology to calculate greenhouse gas emissions. Overall, it was found that the total carbon footprint across the entire supply chain is 4.82 kg CO 2e kg -1 green coffee. The carbon footprint of the processes in Costa Rica to produce 1 km of green coffee is 1.77 kg CO 2e. The processes within Europe generate 3.05 kg CO 2e kg -1 green coffee. This carbon footprint is considered as "very high intensity". This paper also identifies the sources of the most intense emission and discusses mitigation possibilities on which efforts must be focused.
  • Authors:
    • Bonsch, M.
    • Dietrich, J. P.
    • Popp, A.
    • Lotze-Campen, H.
    • Krause, M.
  • Source: Land Use Policy
  • Volume: 30
  • Issue: 1
  • Year: 2013
  • Summary: Conservation of undisturbed natural forests, which are important for biodiversity, carbon storage, and other ecosystem services, affects agricultural production and cropland expansion. We analyze the economic impacts of undisturbed natural forest conservation programs on agriculture and the magnitude of avoided deforestation and avoided carbon emissions in the tropics. We apply a global agricultural land use model to estimate changes in agricultural production costs for the period 2015-2055. Our forest conservation scenarios reflect two different policy goals: either maximize forest carbon storage or minimize impacts on agricultural production. In all the scenarios, the economic impacts on agriculture are relatively low. Production costs would increase due to forest conservation by a maximum of 4%, predominantly driven by increased investments in agricultural productivity increase. We also show regional differences in Latin America, Sub-Saharan Africa, and Southeast Asia, due to different growth rates in food demand, land availability and crop productivity. The area of avoided deforestation does not exceed 1.5 million ha yr(-1) in the period 2015-2055, while avoided carbon emissions reach a maximum of 1.9 Gt CO2 per year. According to our results on the potential changes in agricultural production costs, undisturbed natural forest conservation appears to be a low-cost option for greenhouse gas emission reduction. (C) 2012 Elsevier Ltd. All rights reserved.
  • Authors:
    • La Scala, N.,Jr.
    • Panosso, A. R.
    • Padovan, M. P.
    • Moitinho, M. R.
  • Source: REVISTA BRASILEIRA DE CIENCIA DO SOLO
  • Volume: 37
  • Issue: 6
  • Year: 2013
  • Summary: The soil is one of the main C pools in terrestrial ecosystem, capable of storing significant C amounts. Therefore, understanding the factors that contribute to the loss of CO2 from agricultural soils is critical to determine strategies reducing emissions of this gas and help mitigate the greenhouse effect. The purpose of this study was to investigate the effect of soil tillage and sugarcane trash on CO2 emissions, temperature and soil moisture during sugarcane (re) planting, over a study period of 15 days. The following managements were evaluated: no-tillage with crop residues left on the soil surface (NTR); without tillage and without residue (NTNR) and tillage with no residue (TNR). The average soil CO2 emission (FCO2) was lowest in NTR (2.16 mu mol m(-2) s(-1)), compared to the managements NTNR (2.90 mu mol m(-2) s(-1)) and TNR (3.22 mu mol m(-2) s(-1)), indicating that the higher moisture and lower soil temperature variations observed in NTR were responsible for this decrease. During the study period, the lowest daily average FCO2 was recorded in NTR (1.28 mu mol m(-2) s(-1)), and the highest in TNR (6.08 mu mol m(-2) s(-1)), after rainfall. A loss of soil CO2 was lowest from the management NTR (367 kg ha(-1) of CO2-C) and differing significantly (p<0.05) from the managements NTNR (502 kg ha(-1) of CO2-C) and TNR (535 kg ha(-1) of CO2-C). Soil moisture was the variable that differed most managements and was positively correlated (r = 0.55, p<0.05) with the temporal variations of CO2 emission from NTR and TNR. In addition, the soil temperature differed (p<0.05) only in management NTR (24 degrees C) compared to NTNR (26 degrees C) and TNR (26.5 degrees C), suggesting that under the conditions of this study, sugarcane trash left on the surface induced an average rise in the of soil temperature of 2 degrees C.
  • Authors:
    • Murgueitio Restrepo, E.
    • Ibrahim, M.
    • Montagnini, F.
  • Source: BOIS ET FORETS DES TROPIQUES
  • Issue: 316
  • Year: 2013
  • Summary: Cattle production is part of people's cultures and is important for human nutrition and welfare. However, conventional cattle ranching is a source of greenhouse gas (GHG) emissions. Carbon sequestration in vegetation and soils can be enhanced and GHG emissions reduced with controlled grazing, appropriate pasture species, and the use of silvopastoral systems (SPS), which combine trees and shrubs with pastures. In addition, SPS contribute to climate change adaptation thanks to the ameliorating effects of trees on air temperatures that dry out pastures, as well as improving animal well-being and productivity. Several types of SPS are commonly found in the agricultural landscapes of Latin America. Intensive SPS (ISPS), where fodder banks are combined with woody species planted at high density, produce better yields than conventional ranching thanks to higher cattle density and better weight gain by the animals. Research in Colombia, Nicaragua and Costa Rica shows that SPS have more carbon in aboveground biomass and in soils than degraded pastures. In SPS, the timber or fruit trees, either planted or from natural forest regeneration, increases carbon stocks and sequestration rates. Native tree species can be used in SPS with good results in terms of productivity, soil restoration, carbon sequestration, and biodiversity conservation. The use of SPS contributes to carbon sequestration in trees and in soils, while establishing forest plantations and conserving secondary forests increase carbon sequestration and storage at the landscape level. SPS and especially ISPS can contribute to climate change mitigation because their net GHG emissions can be negative. In Latin America, successful ISPS are being scaled up to regional levels. Incentives such as Payments for Environmental Services along with technical assistance can stimulate the adoption of SPS, thus contributing to climate change mitigation while preserving rural livelihoods.
  • Authors:
    • Ramos-Espinoza, G.
    • Beer, J.
    • Flores-Macias, A.
    • Harmand, J.
    • Payan-Zelaya, F.
    • de Leon Gonzalez, F.
  • Source: Agroforestry Systems
  • Volume: 87
  • Issue: 2
  • Year: 2013
  • Summary: To investigate the effects of microbial inocula and Erythrina poeppigiana pruning residues on soil K, NO3-, and NH4+ concentrations, a greenhouse trial, a field experiment in an organic farm, and three in vitro tests were conducted. Under controlled conditions, weak, temporary effects (10 %) on maize seedling growth were observed on poor soils (taken from the 10-20 cm layer) in the first 2 weeks after application. Positive effects of pruning residue applications on soil K levels (0.09 cmol kg(-1), on average) were detected in both the field and greenhouse study. However, significant effects due to the addition of microbial inocula on soil K concentrations were not detected in the field; thus, microbial applications were ineffective at enhancing nutrient availability under field conditions. In contrast, in the in vitro experiments, CO2 production was 31 % greater than that of untreated soil on the 8th and 15th days of incubation. These results highlight the importance of adding tree pruning residues to support coffee-plant nutrition. Experimental outcome data could be valuable for further studies focused on microbial application dosage and timing.
  • Authors:
    • Mahmood, K.
    • Awan, A. R.
    • Singh, R. K.
    • Stille, L.
    • Akanda, R.
    • Smeets, E. M. W.
    • Wicke, B.
    • Faaij, A. P. C.
  • Source: Journal of Environmental Management
  • Volume: 127
  • Issue: September
  • Year: 2013
  • Summary: This study explores the greenhouse gas balance and the economic performance (i.e. net present value (NPV) and production costs) of agroforestry and forestry systems on salt-affected soils (biosaline (agro) forestry) based on three case studies in South Asia. The economic impact of trading carbon credits generated by biosaline (agro)forestry is also assessed as a potential additional source of income. The greenhouse gas balance shows carbon sequestration over the plantation lifetime of 24 Mg CO2-eq. ha(-1) in a rice-Eucalyptus camaldulensis agroforestry system on moderately saline soils in coastal Bangladesh (case study 1), 6 Mg CO2-eq. ha(-1) in the rice-wheat- Eucalyptus tereticornis agroforestry system on sodic/saline-sodic soils in Haryana state, India (case study 2), and 96 Mg CO2-eq. ha(-1) in the compact tree (Acacia nilotica) plantation on saline-sodic soils in Punjab province of Pakistan. The NPV at a discount rate of 10% is 1.1 k(sic) ha(-1) for case study 1, 4.8 k(sic) ha(-1) for case study 2, and 2.8 k(sic) ha(-1) for case study 3. Carbon sequestration translates into economic values that increase the NPV by 1-12% in case study 1, 0.1 -1% in case study 2, and 2-24% in case study 3 depending on the carbon credit price (1-15 (sic) Mg-1 CO2-eq.). The analysis of the three cases indicates that the economic performance strongly depends on the type and severity of salt-affectedness (which affect the type and setup of the agroforestry system, the tree species and the biomass yield), markets for wood products, possibility of trading carbon credits, and discount rate. (C) 2013 Elsevier Ltd. All rights reserved.
  • Authors:
    • Yeh, S.
    • Yui, S.
  • Source: Environmental Research Letters
  • Volume: 8
  • Issue: 4
  • Year: 2013
  • Summary: Brazil aims to increase palm oil production to meet the growing national and global demand for edible oil and biodiesel while preserving environmentally and culturally significant areas. As land use change (LUC) is the result of complex interactions between socio-economic and biophysical drivers operating at multiple temporal and spatial scales, the type and location of LUC depend on drivers such as neighboring land use, conversion elasticity, access to infrastructure, distance to markets, and land suitability. The purpose of this study is to develop scenarios to measure the impact of land conversion under three different enforcement scenarios (none, some, and strict enforcement). We found that converting 22.5 million hectares of land can produce approximately 29 billion gallons (110 billion liters) of biodiesel a year. Of that, 22-71% of the area can come from forest land, conservation units, wetland and indigenous areas, emitting 14-84 gCO(2)e MJ(-1). This direct land use emission alone can be higher than the carbon intensity of diesel that it intends to displace for lowering greenhouse gas emissions. This letter focuses narrowly on GHG emissions and does not address socio-economic-ecological prospects for these degraded lands for palm oil or for other purposes. Future studies should carefully evaluate these tradeoffs.