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Knudsen M.T.,Copenhagen University | Knudsen M.T.,University of Aarhus | Fonseca de Almeida G.,Federal University of São Carlos | Langer V.,Copenhagen University | And 2 more authors.
Organic Agriculture | Year: 2011

Growing global trade with organic products has given rise to a debate on the environmental impacts during both production and transport. Environmental hotspots of organic orange juice produced by smallholders in Brazil, processed and imported to Denmark, were identified in a case study using a life cycle approach. Furthermore, small-scale organic orange production was compared with small-scale conventional and large-scale organic orange production in the case study area in Brazil. Transport was the main contributor (58%) to the global warming potential of organic orange juice from small-scale farmers imported to Denmark, followed by the farm stage (23%), especially the truck transport of fresh oranges in Brazil and of reconstituted orange juice in Europe. Non-renewable energy use per hectare was significantly lower on the organic small-scale farms than on the conventional, with a similar pattern for global warming potential and eutrophication. Including soil carbon sequestration in organic plantations widened the difference in global warming potential between organic and conventional. Organic small-scale farms had a higher crop diversity than conventional, which may have a positive effect on biodiversity along with the spontaneous vegetation between the organic orange trees and the absence of toxic pesticides. Comparing small-scale with large-scale organic orange production, crop diversity was higher on the small-scale farms, while global warming potential, eutrophication potential and the use of copper per hectare were significantly lower, indicating that environmental impacts from small-scale differ from large-scale organic farms. © 2011 Springer Science & Business Media BV.


Petersen B.M.,University of Aarhus | Knudsen M.T.,Copenhagen University | Hermansen J.E.,International Center for Research in Organic Food Systems | Halberg N.,University of Aarhus
Journal of Cleaner Production | Year: 2013

Globally, soil carbon sequestration is expected to hold a major potential to mitigate agricultural greenhouse gas emissions. However, the majority of life cycle assessments (LCA) of agricultural products have not included possible changes in soil carbon sequestration. In the present study, a method to estimate carbon sequestration to be included in LCA is suggested and applied to two examples where the inclusion of carbon sequestration is especially relevant: 1) Bioenergy: removal of straw from a Danish soil for energy purposes and 2) Organic versus conventional farming: comparative study of soybean production in China. The suggested approach considers the time of the soil CO2 emissions for the LCA by including the Bern Carbon Cycle Model. Time perspectives of 20, 100 and 200 years are used and a soil depth of 0-100 cm is considered. The application of the suggested method showed that the results were comparable to the IPCC 2006 tier 1 approach in a time perspective of 20 year, where after the suggested methodology showed a continued soil carbon change toward a new steady state. The suggested method estimated a carbon sequestration for the first example when storing straw in the soil instead of using it for bioenergy of 54, 97 and 213 kg C t-1 straw C in a 200, 100 and 20 years perspective, respectively. For the conversion from conventional to organic soybean production, a difference of 32, 60 or 143 kg soil C ha-1 yr-1 in a 200, 100 or 20 years perspective, respectively was found. The study indicated that soil carbon changes included in an LCA can constitute a major contribution to the total greenhouse gas emissions per crop unit for plant products. The suggested approach takes into account the temporal aspects of soil carbon changes by combining the degradation and emissions of CO 2 from the soil and the following decline in the atmosphere. Furthermore, the results from the present study highlights that the choice of the time perspective has a huge impact on the results used for the LCA. For comparability with the calculation of the global warming potential in LCA, it is suggested to use a time perspective of 100 years when using the suggested approach for soil carbon changes in LCA. © 2013 Elsevier Ltd. All rights reserved.


Panneerselvam P.,University of Aarhus | Halberg N.,International Center for Research in Organic Food Systems | Vaarst M.,University of Aarhus | Hermansen J.E.,University of Aarhus
Renewable Agriculture and Food Systems | Year: 2012

In India, the number of farmers converting to organic farming has increased in the recent past despite the lack of government support in providing knowledge and extension to the farmers. The aim of this article is to investigate the perceived relevance, benefits and barriers to a conversion to organic agriculture in three different Indian contexts-in Tamil Nadu, Madhya Pradesh and Uttarakhand states. In each state, 40 farmers from both organic and conventional systems were interviewed. The findings indicated that conventional producers identified production and marketing barriers as the main constraints to adopting organic farming, while the age and education of the farmer were not deemed a problem. Lack of knowledge and lack of institutional support were other barriers to conversion. Some farmers were, however, interested in converting to organic farming in the near future in Madhya Pradesh due to the low cost of production, and in Tamil Nadu and Uttarakhand due to the price premium and health benefits. On the other hand, organic farmers were more concerned with health, environmental and production factors when institutional support was available. The years under conversion were positively associated with reduced input costs in all three states and with increased income in Tamil Nadu and increased yield in Madhya Pradesh. Both organic and conventional farmers found the two production factors, low yield and pest control, to be of major concern. However, organic farms in Madhya Pradesh and Uttarakhand experienced yield increases because most of the farms were in the post-conversion period, while the farms in Tamil Nadu were in the conversion period and experienced yield reduction. The study suggests that the government scheme for compensating yield loss during the conversion period and a price premium may help farmers adopt organic agriculture on a large scale in India. © Copyright Cambridge University Press 2011.


Sorensen C.G.,University of Aarhus | Halberg N.,University Sidi Mohammed Ben Abdellah | Oudshoorn F.W.,University of Aarhus | Petersen B.M.,International Center for Research in Organic Food Systems | Dalgaard R.,2. 0 LCA consultancy
Biosystems Engineering | Year: 2014

Different tillage systems result in different resource uses and environmental impacts. Reduced tillage generates savings in direct energy input and the amount of machinery items needed. As the basics for holistic Life Cycle Assessments, both the influencing direct and indirect energy as sources of greenhouse gas emissions are required. Life Cycle inventories (LCI) were aggregated for a number of optimised machinery systems and tillage scenarios integrating a four crop rotation consisting of spring barley, winter barley, winter wheat and winter rape seed. By applying Life Cycle Assessments to a number of tillage scenarios and whole field operations sequences, the energy efficiency and environmental impact in terms of greenhouse gas emissions (GHG) were evaluated.Results showed that the total energy input was reduced by 26% for the reduced tillage system and by 41% for the no-tillage system. Energy used for traction and machine construction contributed between 6 and 8% of the total GHG emission per kg product. The total emission of GHG was 915g CO2 equivalents per kg product by using the conventional tillage system, 817g CO2 equivalents for the reduced tillage system and 855g CO2 equivalents for the no tillage system. The no tillage system was expected to yield 10% less. The mineralisation in the soil contributed the most (50-60%) to this emission, while the fertiliser production contributed with 28-33%. The results stress the importance of applying a systems approach to capture the implications of, for example, sustained yields as otherwise the environmental benefits can be compromised. © 2014 IAgrE.


Askegaard M.,University of Aarhus | Askegaard M.,The Knowledge Center for Agriculture | Olesen J.E.,University of Aarhus | Rasmussen I.A.,University of Aarhus | And 2 more authors.
Agriculture, Ecosystems and Environment | Year: 2011

Two main challenges facing organic arable farming are the supply of nitrogen (N) to the crop and the control of perennial weeds. Nitrate leaching from different organic arable crop rotations was investigated over three consecutive four-year crop rotations in a field experiment at three locations in Denmark (12 years in total). The experimental treatments were: (i) crop rotation, (ii) catch crop and (iii) animal manure. Nitrate leaching was estimated from measured soil nitrate concentration in ceramic suction cells and modelled drainage. There were significant effects on annual N leaching of location (coarse sand>loamy sand>sandy loam) and catch crops (without>with). Including a grass-clover green manure on 25% of the area did not increase N leaching compared with crop rotations without green manure. Also the application of animal manure did not influence N leaching, probably because even in the manured treatments the application rate was lower than crop demand. The results identify management of crop and soil during autumn as the main determinant of N leaching. Nitrate leaching was lowest for a catch crop soil cover during autumn and winter (avg. 20kgNha-1), a soil cover of weeds/volunteers had on avg. 30kgNha-1, and the largest N leaching losses were found after stubble cultivation (avg. 55kgNha-1). The N leaching losses increased with increasing number of autumn soil cultivations. © 2011 Elsevier B.V.


Knudsen M.T.,Copenhagen University | Yu-Hui Q.,China Agricultural University | Yan L.,China Agricultural University | Halberg N.,International Center for Research in Organic Food Systems
Journal of Cleaner Production | Year: 2010

Growing global trade with organic products has increased the demand for environmental impact assessments during both production and transport. Environmental hotspots of organic soybeans produced in China and imported to Denmark were identified in a case study using a life cycle assessment approach. Furthermore, environmental impacts of organic and conventional soybeans at farm gate were compared in the case study. The total global warming potential (GWP) per ton organic soybeans imported to Denmark revealed that 51% came from transportation and 35% from the farm level. Comparing organic and conventional soybean at farm gate showed that GWP, non-renewable energy use, acidification and eutrophication was lower per ton organic soybeans, whereas land use was slightly higher. © 2010 Elsevier Ltd. All rights reserved. Conventional LCA Soybean Organic Transport.


Qiao Y.,China Agricultural University | Halberg N.,International Center for Research in Organic Food Systems | Vaheesan S.,Helvetas Sri Lanka | Scott S.,University of Waterloo
Renewable Agriculture and Food Systems | Year: 2015

Organic agriculture has the potential to provide improved livelihood opportunities, increased income and social benefits for resource-poor small-scale farmers. It has thus become a popular strategy for economic development and poverty reduction in many areas of the global south. However, there has been limited empirical research regarding the actual benefits of certified organic production, particularly when organic is combined with fair trade certification, and for small-scale farmers who are not engaged in coffee or banana production. Further research is needed to demonstrate experiences of farmers under diverse socioeconomic conditions, organizational contexts and degrees of market access. To address these gaps, two surveys of certified organic and fair trade tea producers in China and Sri Lanka were undertaken to investigate the contributions of organic crops to the household economy. In both cases, organic production required lower investment in terms of external inputs but a higher input of farmers’ labor. The price premium received by farmers for the organic tea compensated for the extra labor input and lower yield, resulting in a net profit. However, given the relatively small plots of tea gardens of each household, organic production could not fully provide for the households’ livelihood. Non-farm income dominated the total income of the households across the study cases, despite the earnings from organic farming. In both sites, market-oriented organic tea projects have created more options for paid work locally, which benefits women of reproductive age. Social benefits of organic farming were also reported. Pursuing fair trade certification on top of organic production facilitated farmer organizing, training and community development. Organic agriculture and fair trade certification offer important prospects to improve the livelihoods of small-scale farmers in other, less favored areas of Asia. These forms of certified production could provide economic and social benefits in instances where farm income is the main source of household income. Copyright © Cambridge University Press 2015


Halberg N.,International Center for Research in Organic Food Systems | Hermansen J.E.,University of Aarhus | Kristensen I.S.,University of Aarhus | Eriksen J.,University of Aarhus | And 2 more authors.
Agronomy for Sustainable Development | Year: 2010

Organic rules for grazing and access to outdoor areas in pig production may be met in different ways, which express compromises between considerations for animal welfare, feed self-reliance and negative environmental impact such as greenhouse gas emissions and nitrate pollution. This article compares the environmental impact of the main organic pig systems in Denmark. Normally, sows are kept in huts on grassland and finishing pigs are raised in stables with access to an outdoor run. One alternative practice is also rearing the fattening pigs on grassland all year round. The third method investigated was a one-unit pen system mainly consisting of a deep litter area under a climate tent and with restricted access to a grazing area. Using life cycle assessment (LCA) methodology, the emissions of greenhouse gases of the free range system were estimated to be 3.3 kg CO2-equivalents kg-1 live weight pig, which was significantly higher than the indoor fattening system and the tent system, yielding 2.9 and 2.8 kg CO2-eq. kg-1 pig, respectively. This was 7-22% higher compared with Danish conventional pig production but, due to the integration of grass-clover in the organic crop rotations these had an estimated net soil carbon sequestration. When carbon sequestration was included in the LCA then the organic systems had lower greenhouse gas emissions compared with conventional pig production. Eutrophication in nitrate equivalents per kg pig was 21-65% higher in the organic pig systems and acidification was 35-45% higher per kg organic pig compared with the conventional system. We conclude that, even though the free range system theoretically has agro-ecological advantages over the indoor fattening system and the tent system due to a larger grass-clover area, this potential is difficult to implement in practice due to problems with leaching on sandy soil. Only if forage can contribute to a larger proportion of the pigfeed uptake may the free range system be economically and environmentally competitive. Improvement of nitrogen cycling and efficiency is the most important factor for reducing the overall environmental load from organic pig meat. Presently, a system with pig fattening in stables and concrete-covered outdoor runs seems to be the best solution from an environmental point of view. © 2010 INRA, EDP Sciences.


Panneerselvam P.,University of Aarhus | Hermansen J.E.,University of Aarhus | Halberg N.,International Center for Research in Organic Food Systems
Journal of Sustainable Agriculture | Year: 2011

This study compared farm production, crop yield, input cost, and income in organic and conventional farming systems in three states of India: Uttarakhand, Madhya Pradesh, and Tamil Nadu. The results showed that organic farming reduced the input cost without affecting the net margin in all three states. Total food production was found to be comparable for the two systems in two of three states. While yield of rice and wheat generally was lower under the organic systems, yield from intercropping food crops was generally higher. The number of agro-ecological methods and percentage of farms practicing different agro-ecological methods were higher under organic systems than conventional systems. These results suggest that organic farming has the potential to improve food security of small farmers by reducing indebtedness due to the lower cost of production without affecting total farm production and farm income. © Taylor & Francis Group, LLC.


Halberg N.,International Center for Research in Organic Food Systems
Canadian Journal of Plant Science | Year: 2012

The debate over agricultural sustainability continues due to the challenges of reducing externalities of intensive farming methods and preserving vital natural capital, but many definitions of sustainability are too wide to allow for a prioritized assessment. This paper uses a more narrow definition of agricultural sustainability focusing on the functional integrity of a system to highlight specific aspects of vital importance for the longterm resilience and reproducibility of agricultural systems. Key areas of resource sufficiency are also identified. Based on a review of scientific literature the relative sustainability of organic agriculture is assessed with a focus on environmental impact and resource use in Europe and North America. While there are many examples of organic agriculture with improved performance in terms of soil fertility and preservation of biodiversity, in other aspects - such as resource use per kilogram product - the difference to conventional farming is less important. The paper presents a framework for selection of indicators based on the principles of organic agriculture which may be used to monitor and improve the performance of organic agriculture with respect to functional integrity and resource sufficiency. The differences between comparable organic farms may be used for improving farm practices through a benchmarking process.

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