• Authors:
    • Huang, J. Y.
    • Yao, B.
    • Hu, Q. W.
    • Nie, L. Q.
    • Fu, S.
  • Source: Zhongguo Shengtai Nongye Xuebao / Chinese Journal of Eco-Agriculture
  • Volume: 22
  • Issue: 10
  • Year: 2014
  • Summary: Agricultural productions are very sensitive to climate change. Controlling agricultural greenhouse gases emissions is not only a key issue in China's efforts to address global climate change, but also an essential part of the country's drive to accelerate the shift in its agricultural development modes. For agriculture, crops and soils have substantial carbon sequestration potential. However, agricultural production has induced large amounts of carbon emissions due to the usage of chemical fertilizers, pesticides, machineries and other agricultural materials. Hence, developing low-carbon agriculture has largely depended on increasing carbon efficiency of crop production. Previous studies on carbon efficiency of agricultural production had concentrated on the effects of agricultural management and planting structure on carbon efficiency. However, studies on the spatial and temporal variations in regional agricultural carbon efficiency had remained extremely unavailable, especially the underlying driving factors. As the main grain production base in Jiangxi Province, Poyang Lake Eco-Economic Region has been promoted as a national strategy in 2009. In this study, carbon input and output data of major crop productions in Poyang Lake Eco-Economic Region were obtained from Jiangxi statistical yearbooks for 2001-2011. Subsequently, carbon production efficiency, carbon economic efficiency and carbon ecological efficiency of crops were calculated at county scale. The objectives of this study were (1) to clarify the spatial and temporal patterns of carbon efficiencies of various crops in Poyang Lake Eco-Economic Region, and (2) to discuss the underlying driving factors of the spatial-temporal variations. Results showed that carbon production efficiency of crops varied from 9.27 to 10.16 kg.kg -1(CE) during 2000-2010. The variation pattern could be separated into three phase as "decline phase (2000-2003), smooth phase (2004-2007) and increasing phase (2008-2010)". Carbon economic efficiency of crops fluctuated but followed a downward trend with a range of 10.73 to 9.25 Yuan.kg -1 (CE) in 2000-2010. Carbon ecological efficiency of crops ranged from 1.76 to 1.94 kg(C).kg -1(CE) in 2000-2010. This was further divided into three phases as continuous declining phase (2000-2003), smooth development phase (2004-2007) and continuous growth phase (2008-2010). Furthermore, carbon efficiency of crops showed a significantly characteristic spatial concentration in Poyang Lake Eco-Economic Region; where high carbon efficiency zones were mainly concentrated in the southeast of the region for most of the years. However, low carbon efficiency zones were mainly concentrated in the counties around Jiujiang City. In the case of stable carbon input, carbon production efficiency of crops was mainly influenced by the level of agricultural development and crop yield. Carbon economic efficiency was mostly controlled by grain production and pricing system. The ecological efficiency of carbon was mainly driven by agricultural carbon output. Most counties in Poyang Lake Eco-Economic Region were agricultural carbon-sinks, which needed to be maintained by sustainable low-carbon agricultural developments.
  • Authors:
    • Bjornsson,L.
    • Prade,T.
  • Source: Proceedings of the 9th International Conference on Life Cycle Assessment in the Agri-Food Sector
  • Year: 2014
  • Summary: In an analysis of climate effects, increased soil organic carbon will have a dual effect due to both increased soil fertility and carbon sequestration. Even so, soil carbon changes are neglected in many crop production LCAs. In the present study, the introduction of grass-clover crops in cereal-dominated crop production was evaluated. The grass-clover crops were used for biogas production, and the digested residue was recycled to the farm as biofertilizer. A shift from the cereal-dominated crop rotation to integrated production of food crops and one or two years of grass-clover crops used as biogas feedstock would result in avoided emissions of 2-3 t CO 2-eq. ha -1 a -1. Integrated food and energy crop production would in this case improve soil organic carbon content at the same time as resulting in considerably decreased greenhouse gas emissions from the cultivation system.
  • Authors:
    • Durlinger,B.
    • Tyszler,M.
    • Scholten,J.
    • Broekema,R.
    • Blonk,H.
  • Source: Proceedings of the 9th International Conference on Life Cycle Assessment in the Agri-Food Sector
  • Year: 2014
  • Summary: Agri-footprint is a new life cycle inventory database that focuses on the agriculture and food sector. The goal of this database is to support life cycle assessment practitioners to perform high quality assessments. The database contains a methodologically consistent dataset for a large number of crops, crop products, animal systems and animal products. These inventories can be used as secondary data in LCAs. Non-LCA models were used to calculate a wide array of elementary flows (such as land use change, water use, fertilizer application rates), to support assessment on a multitude of environmental issues. To safeguard relevance and data quality, the database will be updated regularly. As the public interest in food LCAs is expected to increase in the near future, Agri-footprint will be a helpful resource for practitioners in this field.
  • 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:
    • Prade,T.
    • Svensson,S. E.
    • Bjornsson,L.
  • Source: Proceedings of the 9th International Conference on Life Cycle Assessment in the Agri-Food Sector
  • Year: 2014
  • Summary: Changes of soil organic carbon (SOC) content can have a substantial effect on greenhouse gas emissions, but are rarely included in crop production LCAs. SOC content strongly influences soil fertility and therefore crop yields, but is declining in many European soils. The present study investigated if integration of 1-2 years of grass-clover crops in a cereal-dominated crop rotation can increase the SOC pool and how this would impact food production. Results show that when grass-clover crops are integrated, the potential SOC content at steady state will be 41 to 52% higher than in the conventional cereal-dominated crop rotation. The net increase of wheat yields based on SOC improvements indicate that for a crop rotation with one year of grass-clover crops, the initial loss of food production can be counterbalanced due to the impact on fertility of the SOC increase.
  • Authors:
    • Saxe,H.
    • Hamelin,L.
    • Hinrichsen,T.
    • Wenzel,H.
  • Source: Web Of Knowledge
  • Year: 2014
  • Summary: With the rising atmospheric carbon dioxide concentration [CO 2], crops will assimilate more carbon. This will increase yields in terms of carbohydrates but dilute the content of protein and minerals in crops. This consequential life cycle assessment study modelled the environmental consequences that such altered chemical composition and crop yields would have for the production of pig feed. Results revealed, among others, that an extra European demand of pig feed under an atmospheric [CO 2] of 550 mole mole -1 would lead to ca. 6% less expansion of additional arable land worldwide, in comparison to feed produced under today's conditions. However, this did not translate into lower greenhouse gas emissions, because the benefit of increased crop yield was counteracted by changes in the composition of the feed formulation. Among the important changes, feed produced under high [CO 2] was shown to integrate 23% more soymeal and 5% less wheat than at present.
  • Authors:
    • Stamatiadis,S.
    • Evangelou,L.
    • Yvin,J. -C
    • Tsadilas,C.
    • Mina,J. M. G.
    • Cruz,F.
  • Source: Journal of Applied Psychology
  • Volume: 27
  • Issue: 1
  • Year: 2014
  • Summary: A greenhouse experiment was conducted to evaluate the effects of foliar application of an Ascophyllum nodosum seaweed extract (AZAL5) on the growth, nutrient uptake, and yield of winter wheat in a surface soil of the Thessaly Plain classified as TypicXerorthent. Twelve treatment combinations in a randomized complete block design with a factorial arrangement were composed of two rates of inorganic fertilizer (0 and 50 ppm N), three rates of AZAL5 (0, 1.5, and 3 % diluted extract), and two levels of water supply (75 and 45 % of field capacity). Under soil P and K sufficiency, the addition of fertilizer N greatly increased grain yield and nutrient uptake in the shoots (N and K) and grain (N, P, and K). Reduced water supply decreased grain yield and caused water stress as evidenced by decreased Δ13C in the N-deficient treatments and decreased nutrient uptake. AZAL5 application caused increased grain K uptake and a 25 % increase in yield only when mineral N was added. Differences in the efficacy of the two AZAL5 concentrations indicated that optimal dilution ratios were directly or indirectly dependent on soil water content. Complex interaction effects between AZAL5 and water supply on grain Δ13C could not be explained by conventional physiological response to water stress. The lack of biomass, nutrient content, and Δ13C differences between AZAL5 and control treatments in the shoot indicated that the reproductive organs of wheat were the main site of biostimulant action. Overall, the results underline the potential of this product to enhance the effectiveness of inorganic N fertilizers in intensively managed cropping systems under optimal irrigation, deficit irrigation, or rainfed conditions. © 2014, Springer Science+Business Media Dordrecht.
  • Authors:
    • Goge,Fabien
    • Gomez,Cecile
    • Jolivet,Claudy
    • Joffre,Richard
  • Source: Geoderma
  • Volume: 213
  • Year: 2014
  • Summary: Numerous studies on the prediction of soil properties from visible and near-infrared spectroscopy, based on large libraries at county scale or small size soil libraries at local scales have been reported in literature. However, difficulties appear when large libraries are used to estimate the soil properties of a small area. The aim of this paper was to compare various strategies to predict soil properties of local samples using a French national database. Models were built: i) from the national database alone and ii) from the national database spiked with subsets of the local database. Two regression methods were tested: partial least square [PLS] and a local regression method (fast Fourier transform local weighted [FFT-LW]). No general rule was obtained in this study as the best strategy differed according to the property under study. It seems that when strong spectral features are related to the characteristic under study (as for CaCO3 content), the addition of local samples did not bring a decisive advantage over calibration based on a wide national database. There are three important and encouraging points of this work to emphasize: i) the evidence of the added value brought by the national library for the prediction of some soil properties over a local area, ii) the pertinence of spiking with local samples to the global database to reach accurate predictions, and iii) the interest of the FFT-LW non-linear method. As we examined only one local site with peculiar land-use and geologic characteristics, further researches are needed to elucidate the way in which these results depend on intrinsic properties of the local site samples and on the relationship between spectral features and considered soil properties. (C) 2013 Elsevier B.V. All rights reserved.
  • Authors:
    • Capriel, P.
  • Source: European Journal of Soil Science
  • Volume: 64
  • Issue: 4
  • Year: 2013
  • Summary: In the last 60 years traditional agriculture in industrialized European countries, which had initially been dependent on available natural resources, has shifted towards a massive intensification of nutrient turnover because of cheap energy and low-cost synthetic fertilizers. At the same time farm structure has undergone profound changes, resulting in an increase in the number of specialized farms to the detriment of traditional non-specialized ones. All these trends have had a significant impact on agricultural management. The intensification of agricultural management together with climate change could affect the quantity and quality of soil organic matter (SOM). That could imply decreasing soil fertility, reduced harvest yields, increasing nutrient losses and additional greenhouse gas emission. In order to measure the long-term development of SOM in agricultural soils a monitoring programme was initiated in Bavaria in 1986. The measurements are based on 92 representative plots located on cropland and 21 plots located on managed permanent grassland. Between 1986 and 2007 the monitoring plots have been sampled four times. The monitoring results suggest a decrease of soil organic carbon content, total nitrogen content and C:N ratio in cropland as well as in grassland in Bavaria between 1986 and 2007. Crops and organic fertilizers are together with the initial SOM content the main causes of the observed changes in SOM quantity and quality. A climatic effect could be neither proved nor excluded. The results in Bavaria are consistent with the reported changes in organic carbon of agricultural soils in Austria, Belgium, France, the Netherlands and England. In Bavaria we should expect declining SOM stocks, particularly soil organic carbon, in agricultural soils if the supply of organic matter remains constant or even decreases.
  • Authors:
    • Zeng, A.
    • Zhou, J.
    • Mao, X.
    • Dong, G.
  • Source: Ecological Economics
  • Volume: 91
  • Year: 2013
  • Summary: In recent decades, Chinese agriculture has moved towards higher-energy and higher carbon-input systems to increase food production in the country's limited area of croplands. To investigate the environmental impacts of this trend, this study aimed to develop an "Integrated Life Cycle Assessment and Environmental Input-Output Model" (LCA-EIO Model). Using the tri-scope carbon footprint (CF) accounting method, the agricultural carbon footprint of Zhejiang Province, China was calculated for the years from 1997 to 2007, and the categories and structure of carbon emissions sources were analyzed, including patterns of change. In addition, the carbon intensity of crop farming in Zhejiang Province was examined. While an overall reduction in cropland areas has resulted in a substantial decline in direct greenhouse gas emissions from agricultural production, the proportion of carbon emissions caused by energy and chemical consumption has increased dramatically, and this consumption has become the primary source of carbon emissions. A decomposition analysis also identified the key driving forces of energy-related CF dynamics, such as the machinery-labor substitution effect. The results of the decomposition analysis can support decision makers in understanding and promoting low-carbon output agriculture.