• Authors:
    • Sanabria, C.
    • Rodriguez, E.
    • Xiomara Pullido, S.
    • Loaiza, S.
    • del Pilar Hurtado, M.
    • Gutierrez, A.
    • Gomez, Y.
    • Chaparro, P.
    • Botero, C.
    • Bernal, J.
    • Arguello, O.
    • Rodriguez, N.
    • Lavelle, P.
    • Velasquez, E.
    • Fonte, S.
  • Source: Agriculture, Ecosystems & Environment
  • Volume: 185
  • Year: 2014
  • Summary: In the Orinoco River Basin of eastern Colombia large scale and rapid conversion of natural savannas into commercial agriculture exists as a critical threat for the ecological integrity of this fragile region. The highly acidic and compacted soils inherent to this region require thorough physical and chemical conditioning in order for intensive cropping systems to be established. Assessing the impact of this dramatic soil perturbation on biodiversity, ecosystem services and other elements of the natural capital is an urgent task for designing sustainable management options in the region. To address this need, we evaluated soil macro invertebrate communities and soil-based ecosystem services (climate regulation, hydrologic functions, soil stability provided by macro aggregation and nutrient provision potential) in four major production systems: improved pastures, annual crops (rice, corn and soy bean), oil palm and rubber plantations, and compared them to the original savanna. Fifteen plots of each system were sampled along a 200 km natural gradient of soil and climatic conditions. In each plot, we assessed climate regulation by measuring green house gas emissions (N2O, CH4 and CO2) and C storage in aboveground plant biomass and soil (0-20 cm). Soil biodiversity (macro invertebrate communities) and three other soil-based ecosystem services, were assessed using sets of 12-20 relevant variables associated with each service and synthesized via multivariate analyses into a single indicator for each ecosystem function, adjusted in a range of 0.1-1.0. Savannas yielded intermediate values for most indicators, while each production system appeared to improve at least one ecosystem service. For example, nutrient provision (chemical fertility) was highest in annual cropping systems (0.78 +/- 0.03) due to relatively high concentrations of Ca, Mg, N, K, and available P and low Al saturation. Hydrological functions and climate regulation (C storage and GHG emissions) were generally improved by perennial crops (oil palm and rubber), while indicators for macro invertebrate biodiversity and activity (0.73 +/- 0.05) and soil macro aggregation (0.76 +/- 0.02) were highest within improved pastures. High variability within each system indicates the potential to make improvements in fields with lowest indicator values, while differences among systems suggest the potential to mitigate negative impacts by combining plots with contrasted functions in a strategically designed landscape mosaic. (C) 2014 Elsevier B.V. All rights reserved.
  • Authors:
    • Robertson, R. D.
    • Mueller, C.
  • Source: Agricultural Economics
  • Volume: 45
  • Issue: 1
  • Year: 2014
  • Summary: Assessments of climate change impacts on agricultural markets and land-use patterns rely on quantification of climate change impacts on the spatial patterns of land productivity. We supply a set of climate impact scenarios on agricultural land productivity derived from two climate models and two biophysical crop growth models to account for some of the uncertainty inherent in climate and impact models. Aggregation in space and time leads to information losses that can determine climate change impacts on agricultural markets and land-use patterns because often aggregation is across steep gradients from low to high impacts or from increases to decreases. The four climate change impact scenarios supplied here were designed to represent the most significant impacts (high emission scenario only, assumed ineffectiveness of carbon dioxide fertilization on agricultural yields, no adjustments in management) but are consistent with the assumption that changes in agricultural practices are covered in the economic models. Globally, production of individual crops decrease by 10-38% under these climate change scenarios, with large uncertainties in spatial patterns that are determined by both the uncertainty in climate projections and the choice of impact model. This uncertainty in climate impact on crop productivity needs to be considered by economic assessments of climate change.
  • Authors:
    • Goodrick, I.
    • Nake, S.
    • Banabas, M.
    • Nelson, P. N.
    • Webb, M. J.
    • Gabriel, E.
  • Source: Soil Research
  • Volume: 52
  • Issue: 7
  • Year: 2014
  • Summary: Impacts of palm oil industry expansion on biodiversity and greenhouse gas emissions might be mitigated if future plantings replace grassland rather than forest. However, the trajectory of soil fertility following planting of oil palm on grasslands is unknown. We assessed the changes in fertility of sandy volcanic ash soils (0-0.15 m depth) in the first 25 years following conversion of grassland to oil palm in smallholder blocks in Papua New Guinea, using a paired-site approach (nine sites). There were significant decreases in soil pH (from pH 6.1 to 5.7) and exchangeable magnesium (Mg) content following conversion to oil palm but no significant change in soil carbon (C) contents. Analyses to 1.5 m depth at three sites indicated little change in soil properties below 0.5 m. There was considerable variability between sites, despite them being in a similar landscape and having similar profile morphology. Soil Colwell phosphorus (P) and exchangeable potassium (K) contents decreased under oil palm at sites with initially high contents of C, nitrogen, Colwell P and exchangeable cations. We also assessed differences in soil fertility between soil under oil palm (established after clearing forest) and adjacent forest at two sites. At those sites, there was significantly lower soil bulk density, cation exchange capacity and exchangeable calcium, Mg and K under oil palm, but the differences may have been due to less clayey texture at the oil palm sites than the forest sites. Cultivation of oil palm maintained soil structure and fertility in the desirable range, indicating that it is a sustainable endeavour in this environment.
  • Authors:
    • Cederberg, C.
    • Henders, S.
    • Persson, U. M.
  • Source: GLOBAL CHANGE BIOLOGY
  • Volume: 20
  • Issue: 11
  • Year: 2014
  • Summary: The world's agricultural system has come under increasing scrutiny recently as an important driver of global climate change, creating a demand for indicators that estimate the climatic impacts of agricultural commodities. Such carbon footprints, however, have in most cases excluded emissions from land-use change and the proposed methodologies for including this significant emissions source suffer from different shortcomings. Here, we propose a new methodology for calculating land-use change carbon footprints for agricultural commodities and illustrate this methodology by applying it to three of the most prominent agricultural commodities driving tropical deforestation: Brazilian beef and soybeans, and Indonesian palm oil. We estimate land-use change carbon footprints in 2010 to be 66 tCO(2)/t meat (carcass weight) for Brazilian beef, 0.89 tCO(2)/t for Brazilian soybeans, and 7.5tCO(2)/t for Indonesian palm oil, using a 10year amortization period. The main advantage of the proposed methodology is its flexibility: it can be applied in a tiered approach, using detailed data where it is available while still allowing for estimation of footprints for a broad set of countries and agricultural commodities; it can be applied at different scales, estimating both national and subnational footprints; it can be adopted to account both for direct (proximate) and indirect drivers of land-use change. It is argued that with an increasing commercialization and globalization of the drivers of land-use change, the proposed carbon footprint methodology could help leverage the power needed to alter environmentally destructive land-use practices within the global agricultural system by providing a tool for assessing the environmental impacts of production, thereby informing consumers about the impacts of consumption and incentivizing producers to become more environmentally responsible.
  • Authors:
    • Escobar,N.
    • Ribal,F. J.
    • Clemente,G.
    • Sanjuan,N.
  • Source: Proceedings of the 9th International Conference on Life Cycle Assessment in the Agri-Food Sector
  • Year: 2014
  • Summary: Imported biodiesel has accounted for a large share of the total amount consumed in Spain, the main supplier of which was Argentina at least until anti-dumping duties on biodiesel imports from this origin were approved by the European Commission in November 2013. A consequential LCA is carried out in the present study to compare this pathway, which was the prevailing one until almost 2014, with the alternative of using domestic biodiesel from Used Cooking Oil (UCO). System expansion is performed in order to take the indirect functions of both systems into account, functions arising from interactions between co-products (protein meals) in the animal feed market. The marginal suppliers of these co-products in the international market are identified and emissions from direct and indirect Land Use Change (LUC) are calculated. When they are not considered, imported soybean biodiesel leads to lower GHG emissions, due to the carbon uptake by biomass. However, when global LUC is taken into account, UCO biodiesel generates a much lower impact, because it causes a contraction in the area diverted to biofuel feedstock production in other parts of the world. The results underline the importance of considering emissions from LUC when comparing biodiesel alternatives and, thus, interactions in the global market must be addressed.
  • Authors:
    • Meyer-Aurich, A.
    • Salleh, M. A. M.
    • Hansen, A.
    • Lau, Lek H.
    • Grundman, P.
    • Harsono, S. S.
    • Idris, A.
    • Ghazi, T. I. M.
  • Source: Resources, Conservation and Recycling
  • Volume: 77
  • Year: 2013
  • Summary: This paper presents results from a gate-to-gate analysis of the energy balance, greenhouse gas (GHG) emissions and economic efficiency of biochar production from palm oil empty fruit bunches (EFB). The analysis is based on data obtained from EFB combustion in a slow pyrolysis plant in Selangor, Malaysia. The outputs of the slow pyrolysis plant are biochar, syngas, bio-oil and water vapor. The net energy yield of the biochar produced in the Selangor plant is 11.47 MJ kg(-1) EFB. The energy content of the biochar produced is higher than the energy required for producing the biochar, i.e. the energy balance of biochar production is positive. The combustion of EFB using diesel fuel has the largest energy demand of 2.31 MJ kg(-1) EFB in the pyrolysis process. Comparatively smaller amounts of energy are required as electricity (0.39 MJ kg(-1) EFB) and for transportation of biochar to the warehouse and the field (0.13 MJ kg(-1) EFB). The net greenhouse gas emissions of the studied biochar production account for 0.046 kg CO2-equiv.kg(-1) EFB yr(-1) without considering fertilizer substitution effects and carbon accumulation from biochar in the soil. The studied biochar production is profitable where biochar can be sold for at least 533 US-$t(-1). Potential measures for improvement are discussed, including higher productivity of biochar production, reduced energy consumption and efficient use of the byproducts from the slow pyrolysis.
  • Authors:
    • Melling, L.
  • Source: Planter
  • Volume: 89
  • Issue: 1051
  • Year: 2013
  • Summary: Arable land is among one of the world's most important resources that influences a nation's wealth. In Sarawak, tropical peatland is the last frontier of arable land available for industrial agriculture development. Being the last exploited land resources, it is the least researched soil type among the tropical soils and making it the most least understood. Tropical peats that co-existed with the tropical ecosystem are liken to mineral soils of the tropics and are quite different from temperate peats because they are formed under contrasting climatic (wet and dry seasons) and edaphic conditions. Temperate peats are mainly derived from the remains of low growing plants ( Sphagnum spp., Gramineae spp. and Cyperaceae spp.) which are more cellulosic in nature. Tropical peats, on the other hand, are formed from forest species and hence tend to have large amounts of undecomposed and partially decomposed logs, branches and other plant remains which are more lignified. Recently, there has been an increasing trend in oil palm cultivations on tropical peatland. Conversion of tropical peatland into oil palm plantation in South East Asia has been assumed to enhance decomposition process via peat oxidation due to drainage and water management, which leads to the raising level of greenhouse gas (GHG) emission. It has also been postulated that this process will increase in time with oil palm cultivation. However, the management has its contributing factor towards GHG emission from an oil palm plantation and its after effect of climate change due to peatland conversion. Drainage, compaction and water management formed a part of the development process for oil palm peat planting. To further understand the role of water table on soil carbon (C) flux in tropical peatland, a study on GHG from three different ecosystems on tropical peatland was commissioned i.e. oil palm plantation, secondary forest and tropical peat swamp forest for 12 months using a closed chamber method. The mean water table levels at these three ecosystems were -67.6 cm, -14.7 cm and -3.9 cm, respectively. Mean soil CH 4 flux was lowest at the oil palm plantation (0.003 t CH 4/ha/yr), followed by secondary forest (0.067 t CH 4/ha/yr) and tropical peat swamp forest (0.179 t CH 4/ha/yr). However, even though the mean water table levels in the three ecosystems differed by an average of 42.5 cm, the mean soil CO 2 fluxes were quite similar: oil palm plantation (32.89 t CO 2/ha/yr), secondary forest (41.10 t CO 2/ha/yr) and tropical peat swamp forest (45.08 t CO 2/ha/yr). These findings indicated that on tropical peatland soil CH 4 flux was highly influenced by water table but not soil CO 2 flux. Since the total soil CH 4 flux was much lower compared with soil CO 2 flux, it was concluded that water table was not the most important factor influencing the soil C flux in tropical peatland.
  • Authors:
    • Wollenberg, L.
    • Agrawal, A.
    • Newton, P.
  • Source: Global Environmental Change
  • Volume: 23
  • Issue: 6
  • Year: 2013
  • Summary: The rapid expansion of the production of agricultural commodities such as beef, cocoa, palm oil, rubber and soybean is associated with high rates of deforestation in tropical forest landscapes. Many state, civil society and market sector actors are engaged in developing and implementing innovative interventions that aim to enhance the sustainability of commodity supply chains by affecting where and how agricultural production occurs, particularly in relation to forests. These interventions - in the form of novel or moderated institutions and policies, incentives, or information and technology - can influence producers directly or achieve their impacts indirectly by influencing consumer, retailer and processor decisions. However, the evidence base for assessing the impacts of these interventions in reducing the negative impacts of commodity agriculture production in tropical forest landscapes remains limited, and there has been little comparative analysis across commodities, cases, and countries. Further, there is little consensus of the governance mechanisms and institutional arrangements that best support such interventions. We develop a framework for analyzing commodity supply chain interventions by different actors across multiple contexts. The framework can be used to comparatively analyze interventions and their impacts on commodity production with respect to the spatial and temporal scales over which they operate, the groups of supply chain actors they affect, and the combinations of mechanisms upon which they depend. We find that the roles of actors in influencing agricultural production depends on their position and influence within the supply chain; that complementary institutions, incentives and information are often combined; and that multi-stakeholder collaborations between different groups of actors are common. We discuss how the framework can be used to characterize different interventions using a common language and structure, to aid planning and analysis of interventions, and to facilitate the evaluation of interventions with respect to their structure and outcomes. Studying the collective experience of multiple interventions across commodities and spatial contexts is necessary to generate more systematic understandings of the impacts of commodity supply chain interventions in forest-agriculture landscapes.
  • Authors:
    • Polprasert, C.
    • Patthanaissaranukool, W.
    • Englande, A.
  • Source: Applied Energy
  • Volume: 102
  • Year: 2013
  • Summary: This study aimed to evaluate energy and carbon equivalences (CE) associated with palm oil milling and to evaluate sustainability alternatives for energy consumption. Appropriate ways to reduce carbon emissions were also evaluated. A field survey was carried out to quantify the input and output of energy and materials following the conceptual framework of a carbon-balanced model (CBM), which exclude other non-CO2 greenhouse gases. Survey results indicate that the electrical energy consumption for daily mill start-up averaged 18.7 +/- 5.4 kWh/ton Fresh Fruit Bunches (FFBs). This energy is equivalent to 114.4 +/- 33.2 kWh/ton Crude Palm Oil (CPO) which was found to be offset by that generated in the mills using palm fiber as a solid fuel. Currently, organic residues contained in the wastewater are anaerobically converted to methane. The methane is used as fuel to generate electricity and sold to an outside grid network at a generation rate of 8.1 +/- 2.1 kWh/ton FFB. Based on the CBM approach, carbon emissions observed from the use of fossil energy in palm oil milling were very small; however, total carbon emission from oil palm plantation and palm oil milling were found to be 12.3 kg CE/ton FFB, resulting in the net carbon reduction in CPO production of 2.8 kg CE/ton FFB or 53.7 kg CE/ha-y. Overall, the sum of C-reduction was found 1.2 times greater than that of C-emission. This figure can be increased up to 5.5, if all biomass by-products are used as fuel to generate electricity only. The full potential for carbon reduction from palm oil milling is estimated at 0.94 kW of electric power for every hectare of plantation. This equates to a quantity of 68 kg CE reduced per ton of FFB. Thus, utilization of palm oil biomass can have a significantly high potential as a resource to be used for climate change mitigation by reducing carbon emissions. The findings of this work can be used as a template for policy makers to use in assessing and planning their energy programs. (c) 2012 Elsevier Ltd. All rights reserved.
  • Authors:
    • Hino, M.
    • Ramdani, F.
  • Source: PLOS ONE
  • Volume: 8
  • Issue: 7
  • Year: 2013
  • Summary: Increasing prices and demand for biofuel and cooking oil from importer countries have caused a remarkable expansion of oil palm plantations in Indonesia. In this paper, we attempt to monitor the expansion of oil palm plantations on peat land and in tropical forests. We measure the GHG emissions from the land conversion activities at provincial scale. Using Landsat images from three different periods (1990s, 2000s and 2012), we classified LULC of the Riau Province, which is the largest oil palm producing region in Indonesia. A hybrid method of integration, generated by combining automatic processing and manual analysis, yields the best results. We found that the tropical rainforest cover decreased from similar to 63% in the 1990s to similar to 37% in the 2000s. By 2012, the remaining tropical rainforest cover was only similar to 22%. From the 1990s to the 2000s, conversion of forests and peat lands was the primary source of emissions, total CO2 emitted to the atmosphere was estimated at similar to 26.6 million tCO(2)center dot y(-1), with 40.62% and 59.38% of the emissions from conversion of peat lands and forests, respectively. Between 2000 and 2012, the total CO2 emitted to the atmosphere was estimated at similar to 5.2 million tCO(2).y(-1), with 69.94% and 27.62% of the emissions from converted peat lands and converted forests, respectively. The results show that in the Riau Province, the oil palm industry boomed in the period from 1990 to 2000, with transformation of tropical forest and peat land as the primary source of emissions. The decrease of CO2 emissions in the period from 2000 to 2012 is possibly due to the enforcement of a moratorium on deforestation.