Abstract
Agriculture provides the most essential service to mankind, as production of crops in sufficient amounts is necessary for food security and livelihood. This chapter examines the question of whether organic agriculture can produce enough food to meet future demand. This question relates to a moral imperative and any evaluation must therefore be based on objective scientific facts excluding ideological bias, political correctness, economic incentives or environmental opinions. The chapter begins by defining the conditions necessary for a stringent evaluation of crop yields and explains potential pitfalls. Yield data from national statistics, organic and conventional long-term experiments and comparative studies are then compiled and evaluated, followed by a discussion of the main factors behind low-yielding production. In a global perspective, the scientific literature shows that organic yields are between 25 and 50% lower than conventional yields, depending on whether the organic system has access to animal manure. The amount of manure available on organic farms is usually not sufficient to produce similar crop yields as in conventional systems and therefore green manures are commonly used. However, organic crop yields reported for rotations with green manure require correction for years without crop export from the field, which reduces average yield over the crop rotation. When organic yields are similar to those in conventional production, nutrient input through manure is usually higher than nutrient addition in conventional agriculture, but such high inputs are usually only possible through transfer of large amounts of manure from conventional to organic production. The main factors limiting organic yields are lower nutrient availability, poorer weed control and limited possibilities to improve the nutrient status of infertile soils. It is thus very likely that the rules that actually define organic agriculture, i.e. exclusive use of manures and untreated minerals, greatly limit the potential to increase yields. Our analysis of some yield-related statements repeatedly used by advocates of organic agriculture reached the following conclusions: Organic manure is a severely limited resource, unavailable in quantities sufficient for sustaining high crop yields; legumes are not a free and environmentally sound N source that can replace inorganic fertilisers throughout; and low native soil fertility cannot be overcome with local inputs and untreated minerals alone.
Agricultural methods severely limiting crop yields are counter-productive. Lower organic yields require compensation through expansion of cropland – the alternative is famine. Combining expected population growth and projected land demand reveals that low-yielding agriculture is an unrealistic option for production of sufficient crops in the future. In addition, accelerated conversion of natural ecosystems into cropland would cause significant loss of natural habitats. Further improvement of conventional agriculture based on innovations, enhanced efficiency and improved agronomic practices seems to be the only way to produce sufficient food supply for a growing world population while minimising the negative environmental impact.
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Alexandratos, N., 1999, World food and agriculture: outlook for the medium and longer term, Proc. Natl. Acad. Sci. U.S.A. 96: 5908–5914.
Aronsson, H., Torstensson, G., and Bergström, L., 2007, Leaching and crop uptake of N, P and K from organic and conventional cropping systems on a clay soil, Soil Use Manage. 23: 71–81.
Badgley, C. and Perfecto, I., 2007, Can organic agriculture feed the world? Renew. Agric. Food Syst. 22: 80–82.
Badgley, C., Moghtader, J., Quintero, E., Zakern, E., Chappell, J., Avilés-Vázquez, K.,Samulon, A., and Perfecto, I., 2007, Organic agriculture and the global food supply, Renew. Agric. Food Syst. 22: 86–108.
Balfour, E.A., 1943, The Living Soil. Faber and Faber Ltd., London, UK, 276p.
Barberi, P., Cozzani, A., Macchia, M., and Bonari, E., 1998, Size and composition of the weed seedbank under different management systems for continuous maize cropping, Weed Res. 38: 319–334.
Bekunda, M.A., Bationo, A., and Ssali, H., 1997, Soil fertility management in Africa: a review of selected research trials, in: Replenishing Soil Fertility in Africa, R.J. Buresh, P.A., Sanchez, and F. Calhourn, eds., SSSA Special Publications No. 51, Madison, WI, pp. 63–79.
Bengtsson, J., Ahnström, J., and Weibull, A-C., 2005, The effect of organic agriculture on biodiversity and abundance: a meta-analysis, J. Appl. Ecol. 42: 261–269.
Bergström, L. and Kirchmann, H., 1999, Leaching of total nitrogen from nitrogen-15-labeled poultry manure and inorganic nitrogen fertilizer, J. Environ. Qual. 28: 1283–1290.
Bergström, L. and Kirchmann, H., 2004, Leaching and crop uptake of nitrogen from nitrogen-15-labeled green manures and ammonium nitrate, J. Environ. Qual. 33: 1786–1792.
Berry, P.M., Sylvester-Bradley, R., Philipps, L., Hatch, D.J., Cuttle, S.P., Rayns, F.W., and Gosling, P., 2002, Is the productivity of organic farms restricted by the supply of available nitrogen? Soil Use Manage. 18: 248–255.
Besson, J., Myre, K., and Niggli, U., 1999, DOK-Versuch: Vergleichende Langzeituntersuchungen in den drei Anbausystemen biologisch dynamisch, organisch-biologisch und konventionell. II. Ertrag der Kulturen: Kartoffeln, 1. und 2. Fruchtfolgeperiode, Schweiz. Landw. Forsch. 31: 127–155 (In German).
Blum, W.E.H., Buesing, J., and Montanella, L., 2004, Research needs in support of the European thematic strategy for soil protection, Trends Analyt. Chem. 23: 680–685.
Borlaug, N.E., 1970, The Green Revolution, Peace and Humanity – Nobel Lecture, December 11, 1970, www.agbioworld.org/biotech-info/topics/borlaug/nobel-speech.html, Agbioworld, Tuskegee Institute, AL 36087-0085, USA. Assessed 24 November 2007.
Borlaug, N.E. and Dowswell, C.R., 1994, Feeding a Human Population that Increasingly Crowds a Fragile Planet, 15th World Congress of Soil Science, Keynote lecture, Supplement to Transactions, Acapulco, Mexico July 10–16, 1994.
Bouwman, A.F., van der Hoek, K.W., Eickhout, B., and Soenario, I., 2005, Exploring changes in world ruminant production systems, Agric. Syst. 84: 121–153.
Bradford, G.E., 1999, Contributions of animal agriculture to meeting global human food demand, Livest. Prod. Sci. 59: 95–112.
Bruinsma, J., 2003, World Agriculture towards 2015/2030–An FAO Perspective. Earthscan, London, UK, 432p.
Burkitt, L.L., Small, D.R., McDonald, J.W., Wales, W.J., and Jenkin, M.L., 2007a, Comparing irrigated biodynamic and conventionally managed dairy farms. 1. Soil and pasture properties, Aust. J. Exp. Agric. 47: 479–488.
Burkitt, L.L., Wales, W.J., McDonald, J.W., Small, D.R., and Jenkin, M.L, 2007b, Comparing irrigated biodynamic and conventionally managed dairy farms. 2. Milk production and composition and animal health, Aust. J. Exp. Agric. 47: 489–494.
Campbell, B., Frost, P., Kirchmann, H., and Swift, M., 1998, A survey of soil fertility management in small-scale farming systems in North Eastern Zimbabwe, J. Sus. Agric. 11(2/3): 19–39.
Cassman, K.G., Döbermann, A.D., and Walters, D.T., 2002, Agroecosystems, N-use efficiency and N management, Ambio 31: 132–140.
Cassman, K.G., Döbermann, A.D., Walters, D.T, and Yang, H, 2003, Meeting cereal demand while protecting natural resources and improving environmental quality, Ann. Rev. Environ. Resour. 28: 10.1–10.44.
Chen, F. and Wan, K., 2005, The impact of organic agriculture on food quantity, food quality and the environment: a Chinese perspective, Soil Use Manage. 21: 73–74.
Clark, M.S., Horwarth, W.R., Shennan, C., Scow, K.M., Lantni, W.T., and Ferris, H., 1999, Nitrogen, weeds, and water as yield-limiting factors in conventional, low-input and organic tomato systems, Agric. Ecosyst. Environ. 73: 257–270.
Dahlin, S., Kirchmann, H., Kätterer, T., Gunnarsson, S., and Bergström, L., 2005, Possibilities for improving nitrogen use from organic materials in agricultural cropping systems, Ambio 34: 288–295.
Delate, K. and Cambardella, C.A., 2004, Agroecosystem performance during transition to certified organic grain production, Agron. J. 96: 1288–1298.
Denison, R.F, Bryant, D.C., and Kearney, T.E., 2004, Crop yields over the first nine years of LTRAS, a long-term comparison of field crop systems in a Mediterranean climate, Field Crops Res. 86: 267–277.
Drinkwater, L.E., Wagoner, P., and Sarrantonio, M., 1998, Legume based cropping systems have reduced carbon, nitrogen losses, Nature 396: 262–265.
Dyson, T., 1999, World food trends and prospects to 2025, Proc. Natl. Acad. Sci. U.S.A. 96: 5929–5936.
Eickhout, B., Bouwman, A.F., and van Zeijts, H., 2006, The role of nitrogen in world food production and environmental sustainability, Agric. Ecosyst. Environ. 116: 4–14.
Eltun, R., Korsaeth, A., and Nordheim, O., 2002, A comparison of environmental, soil fertility, yield, and economical effects in six cropping systems based on an 8-year experiment in Norway, Agric. Ecosyst. Environ. 90: 155–168.
Evans, L.T., 1998, Feeding the Ten Billions – Plants and Population Growth, Cambridge University Press, Cambridge, UK, 247p.
Fagerberg, B., Salomon, E., and Jonsson, S., 1996, Comparisons between conventional and ecological farming systems at Öjebyn, Swedish J. Agric. Res. 26: 169–180.
FAO, 2007, Food and Agriculture Organization of the United Nations, Statistical Yearbook 2005/06, Rome, www.fao.org/statistics/yearbook/vol_1_1/site_en.asp?page=resources. Assessed 28 April 2007.
Finnish Food Safety Authority (EVIRA), 2006, Organic farming 2005 – Statistics, http://www. evira.fi/portal/se/vaxtproduktion_och_foder/ekoproduktion/aktuellt_inom_ekovervakningen/ Loimaa, Plant Production Inspection Centre, Finland. Assessed 20 December 2007.
Fowler, S.M, Watson, C.A., and Wilman, D., 1993, N, P and K on organic farms: herbage and cereal production, purchases and sales, J. Agric. Sci. 120: 353–360.
Gabriel, D., Roschewitz, I., Tscharntke, T., and Thies, C., 2006, Beta diversity at different spatial scales: plant communities in organic and conventional agriculture, Ecol. Appl. 16: 2011–2021.
GeoHive, 2007, global Statistics, World Population Prospects, www.geohive.com/earth/pop_prospects2.aspx. Assessed 27 March 2007.
Giller, K.E. and Cadish, G., 1995, Future benefits from biological nitrogen fixation: an ecological approach to agriculture, Plant Soil 174: 255–277.
Giller, K.E., 1998, Tropical legumes: providers and plunderers of nitrogen, in: Carbon and Nutrient Dynamics in Natural and Agricultural Tropical Ecosystems, L. Bergström and H. Kirchmann, eds., CAB International, Wallingford, UK, pp. 33–45.
Giller, K.E., 2001, Nitrogen Fixation in Tropical Cropping Systems, 2nd edition, CAB International, Wallingford, UK, 423p.
Gilland, B., 2002, World population and food supply. Can food production keep pace with population growth in the next half-century? Food Policy 27: 47–63.
Goulding, K., 2007, Nutrient management on farms, or ‘You get out what you put in’, J. Sci. Food Agric. 87: 177–180.
Granstedt, A., 1995, Studies of the flow, supply and losses of nitrogen and other plant nutrients in conventional and ecological agricultural systems in Sweden, Biol. Agric. Hortic. 11: 51–67.
Gregory, P.J., Ingram, J.S.I., Andersson, R., Betts, R.A., Brovkin, V., Chase, T.N., Grace, P.R., Gray, A.J., Hamilton, N., Hardy, T.B., Howden, S.M., Jenkins, A., Meybeck, M., Olsson, M., Ortiz-Monasterio, I., Palm, C.A., Payn, T.W., Rummukainen, M., Schulze, R.E., Thiem, M., Valentin, C., and Wilkinson, M.J., 2002, Environmental consequences of alternative practices for intensifying crop production, Agric. Ecosyst. Environ. 88: 279–290.
Green, R.E., Cornell, S.J., Scharleman, J.P.W., and Balemford, A., 2005, Farming and the fate of wild nature, Science 307: 550–555.
Hadas, A., Kautsky, L., and Portnoy, R., 1996, Mineralization of composted manure and microbial dynamics in soil as affected by long-term nitrogen management, Soil Biol. Biochem. 28: 733–738.
Halberg, N., Kristensen, E.S., and Kristensen, I.S., 1995, Nitrogen turnover on organic and conventional mixed farms, J. Agric. Environ. Ethics 8: 30–51.
Halberg, N., and Kristensen, I.S., 1997, Expected crop yield loss when converting to organic dairy farming in Denmark, Biol. Agric. Hortic. 14: 25–41.
Hole, D.G., Perkins, A.J., Wilson, J.O., Alexander, I.H., Grice, P.V., and Evans, A.D., 2005, Does organic farming benefit biodiversity? Biol. Conserv. 122: 113–130.
International Federation of Organic Agricultural Movements, 2006, The four principles of organic farming, Bonn, Germany, www.IFOAM.org. Assessed 19 March 2007.
Ivarson, J., and Gunnarsson, A., 2001, Försök med konventionella och ekologiska odlingsformer 1987–1998, Meddelande från Södra Jordbruksförsöksdistriktet Nr 53, Swedish University of Agricultural Sciences, Uppsala, Sweden, 165 pp (In Swedish).
Jensen, E.S., 1987, Seasonal patterns of growth and nitrogen fixation in field-grown pea, Plant Soil 101: 29–37.
Jensen, E.S., 1996, Grain yield, symbiotic N_2 fixation and interspecific competition for inorganic N in pea-barley intercrops, Plant Soil 182: 25–38.
Kaffka, S. and Koepf, H., 1989, A case study on the nutrient regime in sustainable farming, Biol. Agric. Hortic. 6: 89–106.
Kirchmann, H., 1985, Losses, plant uptake and utilisation of manure nitrogen during a production cycle, Acta Agric. Scand. 24(Suppl.): 77.
Kirchmann, H., Persson, J., and Carlgren, K., 1994, The Ultuna long-term soil organic matter experiment, 1956–1991, Swedish University of Agricultural Sciences, Department of Soil Sciences, Report 17, Uppsala, Sweden, 55p.
Kirchmann, H. and Lundvall, A., 1998, Treatment of solid animal manures: identification of low NH_3 emission practices, Nutr. Cycl. Agroecosyst. 51: 65–71.
Kirchmann, H., Nyamangara, J., and Cohen, Y., 2005, Recycling municipal wastes in the future: from organic to inorganic forms? Soil Use Manage. 21: 152–159.
Kirchmann, H., Bergström, L., Kätterer, T., Mattsson, L., and Gesslein, S., 2007, Comparison of long-term organic and conventional crop-livestock systems in a previously nutrient- depleted soil in Sweden, Agron. J. 99: 960–972.
Kirchmann, H., Kätterer, T., and Bergström, L., 2008, Nutrient supply in organic agriculture – plant availability, sources and recycling, in: Organic Crop Production – Ambitions and Limitations, H. Kirchmann and L. Bergström, eds., Springer, Dordrecht, The Netherlands.
Kitchen, J.L., McDonald, G.K., Shepherd, K.W., Lorimer, M.F., and Graham, R.D., 2003, Comparing wheat grown in South Australian organic and conventional farming systems, I. Growth and grain yield, Aust. J. Agric. Res. 54: 889–901.
Koepf, H.H., Pettersson, B.D., and Schaumann, W., 1976, Biologische Landwirtschaft, Verlag Eugen Ulmer, Stuttgart, Germany, 303 pp (In German).
Korsaeth, A. and Eltun, R., 2000, Nitrogen mass balances in conventional, integrated and ecological cropping systems and the relationship between balance calculations and nitrogen runoff in an 8-year field experiment in Norway, Agric. Ecosyst. Environ. 79: 199–214.
Laryea, K.B., Anders, M.M., and Pathak, P., 1995, Long-term experiments on Alfisols and Vertisols in the semiarid tropics, in: Soil Management: Experimental Basis for Sustainability and Environmental Quality, R. Lal and B.A. Stewart, eds., CRC Press, Boca Raton, FL, pp. 267–292.
Latif, M.A., Islam, M.R., Ali, M.Y., and Saleque, M.A., 2005, Validation of the system of rice intensification (SRI) in Bangladesh, Field Crops Res. 93: 281–292.
Leu, A., 2004, Organic agriculture can feed the world, Acres – a Voice for Eco-Agric. 34(1): 1–4.
Liebhardt, W.C., Andrews, R.W., Culik, M.N., Harwood, R.R., Janke, R.R., Radke, J.K., and Rieger-Schwartz, S.L., 1989, Crop production during conversion from conventional to low-input methods, Agron. J. 81: 150–159.
Lockeretz, W., Shearer, G., Sweeney, S., Kuepper, G., Wanner, D., and Kohl, D.H., 1980, Maize yields and soil nutrient levels with and without pesticides and standard commercial fertilisers, Agron. J. 72: 65–72.
Lockeretz, W., Shearer, G., and Kohl, D.H., 1981, Organic farming in the corn belt, Science 211: 540–547.
Marstorp, H. and Kirchmann, H., 1991, Carbon and nitrogen mineralization and crop uptake of nitrogen from six green manure legumes decomposing in soil, Acta Agric. Scand. 41: 243–252.
Mäder, P., Fliesbach, A., Dubois, D., Gunst, L., Fried, P., and Niggli, U., 2002, Soil fertility and biodiversity in organic farming, Science 296: 1694–1697.
Murwira, H.K. and Kirchmann, H., 1993, Nitrogen dynamics and maize growth in a Zimbabwean sandy soil under maize fertilisation, Commun. Soil Sci. Plant Anal. 24: 2343–2359.
Mugwira, L.M. and Nyamangara, J., 1998, Organic carbon and plant nutrients in soil under maize in Chinamhora communal area, Zimbabwe, in: Carbon and Nutrient Dynamics in Natural and Agricultural Tropical Ecosystems, L. Bergström and H. Kirchmann, eds., CAB International, Wallingford, UK, pp. 15–21.
National Research Council, 1989, Alternative Agriculture, National Academy Press, Washington, DC, 448p.
Nolte, C. and Werner, W., 1994, Investigations on the nutrient cycle and its components of a biodynamically-managed farm, Biol. Agric. Hortic. 10: 235–254.
Nonhebel, S., 2005, Renewable energy and food supply: will there be enough land? Renew. Sus. Energ. Rev. 9: 191–201.
Nguyen, M.L., Haynes, R.J., and Goh, K.M., 1995, Nutrient budgets and status in three pairs of conventional and alternative mixed cropping farms in Canterbury, New Zealand, Agric. Ecosyst. Environ. 52: 149–162.
Palm, C.A., Myers, R.J.K., and Nandwa, S.M., 1997, Combined use of organic and inorganic nutrient sources for soil fertility maintenance and replenishment, in: Replenishing Soil Fertility in Africa, R.J. Buresh, P.A. Sanchez, and F. Calhourn, eds., SSSA Special Publications No. 51, Madison, WI, pp. 193–217.
Palm, C.A., Gachengo, C.N., Delve, G., Cadish, G., and Giller, K.E., 2001, Organic inputs for soil fertility management in tropical agroecosystems: application of an organic resource database, Agric. Ecosyst. Environ. 83: 27–42.
Pang, X.P. and Letey, J., 2000, Organic farming: challenges of timing nitrogen availability to crop nitrogen requirements, Soil Sci. Soc. Am. J. 64: 247–253.
Parry, M., Rosenzweig, C., and Livermore, M., 2005, Climate change, global food supply and risk of hunger, Philosophical Trans. R. Soc. B: Biol. Sci. 360: 2125–2138.
Peigné, J., Ball, B.C., Roger-Estrade, J., and David, C., 2007, Is conservation tillage suitable for organic farming? A review, Soil Use Manage. 23: 129–144.
Pieri, C., 1995, Long-term soil management experiments in semiarid Francophone Africa, in: Soil Management: Experimental Basis for Sustainability and Environmental Quality, R. Lal and B.A. Stewart, eds., CRC Press, Boca Raton, FL, pp. 225–266.
Pimentel, D., Hepperley, P., Hanson, J., Douds, D., and Seidel, R., 2005, Environmental, energetic, and economic comparisons of organic and conventional farming systems, BioScience 55: 673–582.
Porter, P.M., Huggins, D.R., Perillo, C.A., Quirling, S.R., and Crookston, R.K., 2003, Organic and other management strategies with two- and four-year crop rotations in Minnesota, Agron. J. 95: 233–244.
Posner, J.L., Baldock, J.O., and Hedtcke, J.L., 2008, Organic and conventional cropping systems in the Wisconsin integrated cropping systems trials: I. Productivity 1990–2002, Agron. J. 100: 265–260.
Poudel, D.D., Horwarth, W.R., Lanini, W.T., Temple, S.R., and van Bruggen, A.H.C., 2002, Comparison of soil N availability and leaching potential, crop yields and weeds in organic, low-input and conventional farming systems in northern California, Agric. Ecosyst. Environ. 90: 125–137.
Pretty, J.N. and Hine, R.E., 2001, Reducing food poverty with sustainable agriculture: a summary of new evidence, Centre for Environment and Society, Essex University, UK, www.essex.ac.uk/ces/esu/occasionalpapers/SAFE%20FINAL%20-%20Pages1-22.pdf. Assessed 29 December 2007.
Pretty, J.N., Morison, J.L.L., and Hine, R.E., 2003, Reducing food poverty by increasing agricultural sustainability in developing countries, Agric. Ecosyst. Environ. 95: 217–234.
Prudencio, C.Y., 1993, Ring management of soils and crops in the West African semi-arid tropics: the case of the mossi farming systems in Burkina Faso, Agric. Ecosyst. Environ. 47: 237–264.
Quinones, N.A., Borlaug, N.E., and Dowswell, C.R., 1997, A fertilizer-based green revolution for Africa, in: Replenishing Soil Fertility in Africa, R.J. Buresh, P.A. Sanchez and F. Calhourn, eds., SSSA Special Publications No. 51, Madison, WI, pp. 81–95.
Rundgren, G., 2002, Organic Agriculture and Food Security, IFOAM, Dossier 1, Bonn, Germany, 20p.
Rusch, H.P., 1978, Bodenfruchtbarkeit. Eine Studie biologischen Denkens, 3rd Printing. Haug Verlag, Heidelberg, Germany, 243 pp (In German).
Ryan, M.H., Derrick, J.W., and Dann, P.R., 2004, Grain mineral concentrations and yield of wheat grown under organic and conventional management, J. Sci. Food Agric. 84: 207–216.
Sanchez, P.A., 2002, Soil fertility and hunger in Africa, Science 295: 2019–2020.
Sanchez, J.E., Harwood, R.R., Willson, T.C., Kizilkaya, K., Smeenk, J., Parker, E., Paul, E.A., Knezek, B.D., and Robertson, G.P., 2004, Managing soil carbon and nitrogen for productivity and environmental quality, Agron. J. 96: 769–775.
SCB, 2006, Yearbook of Agricultural Statistics, Official Statistics of Sweden, SCB, Örebro, Sweden.
Sheehy, J.E., Peng, S., Dobermann, A., Mitchell, P.L., Ferrer, A., Yang, J., Zou, Y., Zhong, X., and Huang, J., 2004, Fantastic yields in the system of rice intensification: fact or fallacy? Field Crops Res. 88: 1–8.
Singh, L. and Balasubramanian, V., 1979, Effects of continuous fertilizer use on a ferruginous soil (Halustalf) in Nigera, Exp. Agric. 15: 257–265.
Sjursen, H., 2001, Change of weed seed bank during the first complete six-course rotation after conversion from conventional to organic farming, Biol. Agric. Hortic. 19: 71–90.
Smaling, E.M.A. and Braun, A.R., 1996, Soil fertility research in sub-Saharan Africa: new dimensions, new challenges, Commun. Soil Sci. Plant Anal. 27: 365–386.
Smaling, E.M.A., Nandwa, S.M., and Jansson, B., 1997, Soil fertility in Africa is at stake, in: Replenishing Soil Fertility in Africa, R. J. Buresh, P. A. Sachez and F. Calhourn, eds., SSSA Special Publications No. 51, Madison, WI, pp. 47–62.
Smil, V., 2001, Enriching the Earth: Fritz Haber, Carl Bosch, and the Transformation of World Food Production, MIT Press, Cambridge, MA, 338p.
Smil, V., 2002, Nitrogen and food production: proteins for human diets, Ambio 31: 126–131.
Smith, R.G. and Gross, K.L., 2006, Weed community and corn yield variability in diverse management systems, Weed Sci. 54: 106–113.
Smith, R.G., Menalled, F.D., and Robertson, G.P., 2007, Temporal yield variability under conventional and alternative management systems, Agron. J. 99: 1629–1634.
Smolik, J.D., Dobbs, T.L., Rickerl, D.H., Wrage, L.J., Buchenau, G.W., and Machacek, T.A., 1993, Agronomic, economic, and ecological relationships in alternative (organic), conventional, and reduced-till farming systems, Bull. 718, South Dakota Agric. Exp. Stat., Brookings, USA.
Smolik, J.D., Dobbs, T.L., and Rickerl, D.H., 1995, The relative sustainability of alternative, conventional and reduced-till farming systems, Am. J. Altern. Agric. 10: 25–35.
Spiess, E., Stauffer, W., Niggli, U., and Besson, J.M., 1993, DOK-Versuch: Vergleichende Langzeit-Untersuchungen in den drei Anbausystemen biologisch-dynamisch, organisch-biologisch und konventionell. IV. Aufwand und Ertrag: Nährstoffbilanzen, 1. und 2. Fruchtfolgeperiode, Schweiz. Landw. Forsch. 32: 565–579 (In German).
Statistics Finland, 2007, Finland in Figures. Agriculture, Forestry and Fishery, Statistics Finland, Helsinki. http://www.stat.fi/tup/suoluk/suoluk_maatalous_en.html. Assessed 18 December 2007.
Steiner, R., 1924, Geisteswissenschaftliche Grundlagen zum Gedeihen der Landwirtschaft. Steiner Verlag, 5. Auflage 1975. Dornach, Schweiz, 256 pp (In German).
Svensson, K., Odlare, M., and Pell, M., 2004, The fertilizing effect of compost and biogas residues from source separated household waste, J. Agric. Sci. 142: 461–467.
Swift, M.J., Seward, P.D., Frost, P.G.H., Qureshi, J.N., and Muchena, F.N., 1994, Long-term experiments in Africa: developing a database for sustainable land use under global change, in: Long-term Experiments in Agricultural and Ecological Sciences, R.A. Leigh and A.E. Jonston, eds., CAB Int. Wallingford, England, pp. 229–251.
Teasdale, J.R., Rosecrance, R.C., Coffman, C.B., Starr, J.L., Paltineanu, I.C., Lu, Y.C., and Watkins, B.K., 2000, Performance of reduced-tillage cropping systems for sustainable grain production in Maryland, Am. J. Altern. Agric. 15: 79–87.
Teasdale, J.R., Mangum, R.W., Radhakrishnan, J., and Cavigelli, M.A., 2004, Weed seedbank dynamics in three organic farming crop rotations, Agron. J. 96: 1429–1435.
Teasdale, J.R., Coffman, B., and Mangum, R.W., 2007, Potential long-term benefits of no-tillage and organic cropping systems for grain production and soil improvement, Agron. J. 99: 1297–1305.
Toomsan, B., McDonagh, J.F., Limpinuntana, V., and Giller, K.E., 1995, Nitrogen fixation by groundnut and soyabean and residual nitrogen benefits to rice farmers’ fields in Northeast Thailand, Plant Soil 175: 45–56.
Torstensson, G., Aronsson, H., and Bergström, L., 2006, Nutrient use efficiency and leaching of N, P and K of organic and conventional cropping systems in Sweden, Agron. J. 98: 603–615.
TSBF, CIAT, 2006, Integrated soil fertility management in the tropics, http://www.tsbf.org/ pdf/tsbf_ciat_achievements_2002–2005.pdf, Nairobi, Kenya. Assessed 29 December 2007.
Trewavas, A., 2001, The population/biodiversity paradox. Agricultural efficiency to save wilderness, Plant Physiol. 125: 174–179.
Tudge, C., 2005, Can organic farming feed the world? http://www.colintudge.com, Oxford, England. Assessed 29 December 2007.
UN Millennium Project, 2005, Halving Hunger: It Can Be Done, P. Sanchez, ed., Task Force on Hunger. Earthscan, UK, 245p.
Warman, P.R. and Harvard, K.A., 1997, Yield vitamin and mineral contents of organically and conventionally grown carrots and cabbage, Agric. Ecosyst. Environ. 61: 155–162.
Watson, C.A., Atkinson, D., Gosling. P., Jackson, L.R., and Rays, F.W., 2002, Managing soil fertility in organic farming systems, Soil Use Manage. Suppl. 18: 239–247.
Wieser, I., Heβ, J., and Lindenthal, T., 1996, Nutrient balances on organically managed grassland farms in Upper Austria, Die Bodenkultur 47: 81–88.
Woodward, L., 1995, Can organic farming feed the world? www.population-growth-migration. info/essays/woodwardorganic.html, Elm Research Centre, England. Assessed 29 December 2007.
Vandermeer, J. and Perfecto, I., 2007, The agricultural matrix and a future paradigm for conservation, Conserv. Biol. 21: 274–277.
Vanlauwe, B., Wendt, J., and Diels, J., 2001, Combined application of organic matter and fertilizer, in: Sustaining Soil Fertility in West-Africa, G. Tian, F. Ishida and J.D.H. Keatinge, eds., SSSA Special Publications No 58, Madison, WI, pp. 247–280.
Vanlauwe, B. and Giller, K.E., 2006, Popular myths around soil fertility management in sub-Saharan Africa, Agric. Ecosyst. Environ. 116: 34–46.
Vasilikiotis, C., 2000, Can organic farming “Feed the World”? http://nature.berkeley.edu/∼christos/espm118/articles/organic_feed_world.pdf, University of California Berkeley, CA. Assessed 29 December 2007.
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Kirchmann, H., Bergström, L., Kätterer, T., Andrén, O., Andersson, R. (2009). Can Organic Crop Production Feed the World?. In: Kirchmann, H., Bergström, L. (eds) Organic Crop Production – Ambitions and Limitations. Springer, Dordrecht. https://doi.org/10.1007/978-1-4020-9316-6_3
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