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Modeling carbon cycles and estimation of greenhouse gas emissions from organic and conventional farming systems

Published online by Cambridge University Press:  25 February 2008

Björn Küstermann ,
Maximilian Kainz  and
Kurt-Jürgen Hülsbergen
Björn Küstermann*
Affiliation:
Lehrstuhl für Ökologischen Landbau, Technische Universität München, Alte Akademie 12, D-85354 Freising-Weihenstephan, Germany
Maximilian Kainz
Affiliation:
Lehrstuhl für Ökologischen Landbau, Technische Universität München, Alte Akademie 12, D-85354 Freising-Weihenstephan, Germany
Kurt-Jürgen Hülsbergen
Affiliation:
Lehrstuhl für Ökologischen Landbau, Technische Universität München, Alte Akademie 12, D-85354 Freising-Weihenstephan, Germany
*
*Corresponding author: [email protected]
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Abstract

The paper describes the model software REPRO (REPROduction of soil fertility) designed for analyzing interlinked carbon (C) and nitrogen (N) fluxes in the system soil–plant–animal–environment. The model couples the balancing of C, N and energy fluxes with the target to estimate the climate-relevant CO2, CH4 and N2O sources and sinks of farming systems. For the determination of the net greenhouse effect, calculations of C sequestration in the soil, CO2 emissions from the use of fossil energy, CH4 emissions from livestock keeping and N2O emissions from the soil have been made. The results were converted into CO2 equivalents using its specific global warming potential (GWP). The model has been applied in the experimental farm Scheyern in southern Germany, which had been divided into an organic (org) and a conventional (con) farming system in 1992. Rather detailed series of long-term measuring data are available for the farm in Scheyern, which have been used for validating the software for its efficiency and applicability under very different management yet nearly equal site conditions.

The organic farm is multi-structured with a legume-based crop rotation (N2 fixation: 83 kg ha−1 yr−1). The livestock density (LSU=Livestock Unit according to FAO) is 1.4 LSU ha−1. The farm is oriented on closed mass cycles; from the energetic point of view it represents a low-input system (energy input 4.5 GJ ha−1 yr−1). The conventional farm is a simple-structured cash crop system, based on mineral N (N input 145 kg ha−1 yr−1). Regarding the energy consumption, the system is run on high inputs (energy input 14.0 GJ ha−1 yr−1). The organic crop rotation reaches about 57% (8.3 Mg ha−1 yr−1) of the DM yield, about 66% (163 kg ha−1 yr−1) of the N removal and roughly 56% (3741 kg ha−1 yr−1) of the C fixation of the conventional crop rotation. In the organic rotation, 18 GJ per GJ of fossil energy input are bound in the harvested biomass vis-à-vis 11.1 GJ in the conventional rotation. The strongest influence on the greenhouse effect is exerted by C sequestration and N2O emissions. In Scheyern, C sequestration has set in under organic management (+0.37 Mg ha−1 yr−1), while humus depletion has been recorded in the conventional system (−0.25 Mg ha−1 yr−1).

Greenhouse gas emissions (GGEs) due to fuel consumption and the use of machines are nearly on the same level in both crop rotations. However, the conventional system emits an additional 637 kg CO2 eq ha−1 yr−1, which had been consumed in the manufacture of mineral N and pesticides in the upstream industry.

Besides the analyses in the experimental farm Scheyern, the model has been applied in 28 commercial farms (18 org and 10 con) with comparable soil and climate conditions in the surroundings of Scheyern (mean distance 60 km). The program calculations are aimed at benchmarking the results obtained in the farming systems Scheyern; they are expected to disclose management-specific variations in the emission of climate-relevant gases and to rate the suitability of the model for describing such management-specific effects. In order to make the situation in the farms comparable, only the emissions from cropping systems were analyzed. Livestock keeping remained unconsidered. Due to lower N and energy inputs, clearly lower N2O and CO2 emissions were obtained for the organic farms than for the conventional systems.

The analyses have shown possibilities for the optimization of management and the mitigation of GGE. Our findings underline that organic farming includes a high potential for C sequestration and the reduction of GGEs. Currently, the model REPRO is tested by 90 farms in the Federal Republic of Germany with the aim to apply it in the future not only in the field of research but also in the management of commercial farms.

Keywords

carbon cyclefarming systemmodelingglobal warming potentialC sequestrationgreenhouse gas emissionsREPRO
Type
Research Papers
Information
Renewable Agriculture and Food Systems , Volume 23 , Special Issue 1: Researching Sustainable Agricultural Systems, ISOFAR 2005 , March 2008 , pp. 38 - 52
Copyright
Copyright © Cambridge University Press 2008

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References

1 Janzen, H.H. 2004. Carbon cycling in earth systems––a soil science perspective. Agriculture, Ecosystems and Environment 104:399–417.CrossRefGoogle Scholar
2 West, T.O. and Marland, G. 2002. Net carbon flux from agricultural ecosystems: methodology for full carbon cycle analyses. Environmental Pollution 116:439–444.CrossRefGoogle ScholarPubMed
3 Robertson, G.P., Paul, E.A., and Harwood, R.R. 2000. Greenhouse gases in intensive agriculture: contributions of individual gases to the radiative forcing of the atmosphere. Science 289:1922–1925.CrossRefGoogle Scholar
4 Su, Y.Z. 2006. Soil carbon and nitrogen sequestration following the conversion of cropland to alfalfa forage land in northwest China. Soil and Tillage Research 92:181–189.CrossRefGoogle Scholar
5 Smith, P. 2004. Carbon sequestration in croplands: the potential in Europe and the global context. European Journal of Agronomy 20:229–236.CrossRefGoogle Scholar
6 Lovett, D.K., Shalloo, L., Dillon, P., and O'Mara, F.P. 2006. A systems approach to quantify greenhouse gas fluxes from pastoral dairy production as affected by management regime. Agricultural Systems 88:156–179.CrossRefGoogle Scholar
7 Haas, G., Geier, U., Schulz, D.G., and Köpke, U. 1995. Vergleich konventioneller und organischer Landbau. Teil I: Klimarelevante Kohlendioxid-Emission durch den Verbrauch fossiler Energie. Berichte über Landwirtschaft 73:401–415.Google Scholar
8 Flessa, H., Ruser, R., Dörsch, P., Kamp, T., Jimenez, M.A., Munch, J.C., and Beese, F. 2002. Integrated evaluation of greenhouse gas emissions (CO2, CH4, N2O) from two farming systems in southern Germany. Agriculture, Ecosystems and Environment 91:175–189.CrossRefGoogle Scholar
9 Lewis, K.A., Newbold, M.J., and Tzilivakis, J. 1999. Developing an emissions inventory from farm data. Journal of Environmental Management 55:183–197.CrossRefGoogle Scholar
10 Hülsbergen, K.-J., Feil, B., Biermann, S., Rathke, G.-W., Kalk, W.-D., and Diepenbrock, W. 2001. A method of energy balancing in crop production and its application in a long-term fertilizer trial. Agriculture, Ecosystems and Environment 86: 303–321.CrossRefGoogle Scholar
11 Schröder, P., Huber, B., Olazabal, U., Kämmerer, A., and Munch, J.C. 2002. Land use and sustainability: FAM Research Network on Agroecosystems. Geoderma 105:155–166.CrossRefGoogle Scholar
12 Hülsbergen, K.-J. 2003. Entwicklung und Anwendung eines Bilanzierungsmodells zur Bewertung der Nachhaltigkeit landwirtschaftlicher Systeme. Shaker Verlag, Aachen.Google Scholar
13 Hülsbergen, K.-J. and Küstermann, B. 2005. Development of an environmental management system for organic farms and its introduction into practice. ISOFAR: Proceedings of the Conference ‘Researching Sustainable Systems’, Adelaide: p. 460–463.Google Scholar
14 Kalk, W.-D., Hülsbergen, K.-J., and Biermann, S. 1998. Management-related material and energy balances for the rating of production intensity and environmental acceptability of land use. Archiv für Acker-, Pflanzenbau und Boden 43:167–182.Google Scholar
15 Hülsbergen, K.-J., Feil, B., and Diepenbrock, W. 2002. Rates of nitrogen application required to achieve maximum energy efficiency for various crops: results of a long-term experiment. Field Crops Research 77:61–76.CrossRefGoogle Scholar
16 Siebrecht, N., Lipski, A., Wenske, K., and Hülsbergen, K.-J. 2006. Integration eines Geographischen Informationssystems in ein Umwelt- und Betriebsmanagementsystem. Proceedings der 26. Jahrestagung der Gesellschaft für Informatik, p. 269–272.Google Scholar
17 Rücknagel, J., Hofmann, B., Paul, R., Christen, O., and Hülsbergen, K.-J. 2007. Estimating precompression stress of structured soils on the basis of aggregate density and dry bulk density. Soil and Tillage Research 92:213–220.CrossRefGoogle Scholar
18 Abraham, J., Hülsbergen, K.-J., and Diepenbrock, W. 1999. Modellierung des Stickstoffhaushaltes landwirtschaftlich genutzter Flächen im Elbeeinzugsgebiet. Mitteilungen der Gesellschaft für Pflanzenbauwissenschaften 12:77–79.Google Scholar
19 IPCC. 2001. Climate Change: The Scientific Basis. Cambridge University Press, Cambridge, UK.Google Scholar
20 Asmus, F. 1992. Einfluss organischer Dünger auf Ertrag, Humusgehalt des Bodens und Humus-reproduktion. Berichte über Landwirtschaft, Sonderheft 206:127–139.Google Scholar
21 Körschens, M., Rogasik, J., and Schulz, E. 2005. Bilanzierung und Richtwerte organischer Bodensubstanz. Landbauforschung Völkenrode 55:1–10.Google Scholar
22 Steingrobe, B., Schmid, H., Gutser, R., and Claassen, N. 2001. Root production and root mortality of winter wheat grown on sandy and loamy soils in different farming systems. Biology Fertility Soils 33:331–339.CrossRefGoogle Scholar
23 Steingrobe, B., Schmid, H., and Claassen, N. 2001. Root production and root mortality of winter barley and its implication with regard to phosphate acquisition. Plant and Soil 237:239–248.CrossRefGoogle Scholar
24 IPCC. 1997. Revised 1996 IPCC Guidelines for National Greenhouse Gas Inventories: Reference Manual. Intergovernmental Panel on Climate Change, Paris.Google Scholar
25 Bolger, T.P., Pate, J.S., Unkovich, M.J., and Turner, N.C. 1995. Estimates of seasonal nitrogen fixation of annual subterranean clover-based pastures using the 15N natural abundance technique. Plant and Soil 175:57–66.CrossRefGoogle Scholar
26 Scheffer, F. and Schachtschabel, P. 1998. Lehrbuch der Bodenkunde. Enke Verlag, Stuttgart.Google Scholar
27 Auerswald, K., Albrecht, H., Kainz, M., and Pfadenhauer, J. 2000. Principles of sustainable land-use systems developed and evaluated by the Munich Research Alliance on Agro-Ecosystems (FAM). Petermanns Geographische Mitteilungen 144:16–25.Google Scholar
28 Auerswald, K., Kainz, M., and Fiener, P. 2003. Soil erosion potential of organic versus conventional farming evaluated by USLE modeling of cropping statistics for agricultural districts in Bavaria. Soil Use and Management 19:305–311.CrossRefGoogle Scholar
29 Meyer-Aurich, A. 2005. Economic and environmental analysis of sustainable farming practices—a Bavarian case study. Agricultural Systems 86:190–206.CrossRefGoogle Scholar
30 Rühling, I., Ruser, R., Kölbl, A., Priesack, E., and Gutser, R. 2005. Kohlenstoff und Stickstoff in Agrarökosystemen. In: Osinski, E., Meyer-Aurich, A., Huber, B., Rühling, I., Gerl, G., and Schröder, P. (eds) Landwirtschaft und Umwelt—ein Spannungsfeld. oekom Verlag, München. p. 99–154.Google Scholar
31 Refsgaard, K., Halberg, N., and Kristensen, E.S. 1998. Energy utilization in crop and dairy production in organic and conventional livestock production systems. Agricultural Systems 57:599–630.CrossRefGoogle Scholar
32 Oenema, O., Kros, H., and de Vries, W. 2003. Approaches and uncertainties in nutrient budgets: implications for nutrient management and environmental policies. European Journal of Agronomy 20:3–16.CrossRefGoogle Scholar
33 Schröder, J.J., Aarts, H.F.M., ten Berge, H.F.M., van Keulen, H., and Neeteson, J.J. 2003. An evaluation of whole-farm nitrogen balances and related indices for efficient nitrogen use. European Journal of Agronomy 20:33–44.CrossRefGoogle Scholar
34 Neufeldt, H., Schäfer, M., Angenendt, E., Li, C., Kaltschmitt, M., and Zeddies, J. 2006. Disaggregated greenhouse gas emission inventories from agriculture via a coupled economic-ecosystem model. Agriculture, Ecosystems and Environment 112:233–240.CrossRefGoogle Scholar
35 Gibbons, J.M., Ramsden, S.J., and Blake, A. 2006. Modeling uncertainty in greenhouse gas emissions from UK agriculture at the farm level. Agriculture, Ecosystems and Environment 112:347–355.CrossRefGoogle Scholar
36 Smith, P. 2004. How long before a change in soil organic carbon can be detected? Global Change Biology 10:1878–1883.CrossRefGoogle Scholar
37 Drinkwater, L.E., Wagoner, P., and Sarrantonio, M. 1998. Legume-based cropping systems have reduced carbon and nitrogen losses. Nature 396: 262–265.CrossRefGoogle Scholar
38 Meyer-Aurich, A., Weersink, A., Janovicek, K., and Deen, B. 2006. Cost efficient rotation and tillage options to sequester carbon and mitigate GHG emissions from agriculture in Eastern Canada. Agriculture, Ecosystems and Environment 117:119–127.CrossRefGoogle Scholar
39 Johnson, M.G., Levine, E.R., and Kern, J.S. 1995. Soil organic matter: distribution, genesis, and management to reduce greenhouse gas emissions. Water, Air and Soil Pollution 82:593–615.CrossRefGoogle Scholar
40 Petersen, S.O., Regina, K., Pöllinger, A., Rigler, E., Valli, L., Yamulki, S., Esala, M., Fabbri, C., Syväsalo, E., and Vinther, F.P. 2006. Nitrous oxide emissions from organic and conventional crop rotations in five European countries. Agriculture, Ecosystems and Environment 112:200–206.CrossRefGoogle Scholar
41 Gregorich, E.G., Rochette, P., VandenBygaart, A.J., and Angers, D.A. 2005. Greenhouse gas contributions of agricultural soils and potential mitigation practices in Eastern Canada. Soil Tillage Research 83:53–72.CrossRefGoogle Scholar
42 Ruser, R., Flessa, H., Schilling, R., Beese, F., and Munch, J.C. 2001. Effect of crop-specific management and N fertilization on N2O emissions from a fine-loamy soil. Nutrient Cycling in Agroecosystems 59:177–191.CrossRefGoogle Scholar
43 Li, C.S. 2000. Modeling trace gas emissions from agricultural ecosystems. Nutrient Cycling in Agroecosystems 58:259–276.CrossRefGoogle Scholar
44 Kalk, W.-D., Hellebrand, H.J., Hülsbergen, K.-J., and Abraham, J. 2005. Kohlenstoffbilanzen landwirtschaftlicher Betriebssysteme unterschiedlicher Produktionsintensität. In: Weigel, H.-J. and Dämmgen, U. (eds) Biologische Senken für Kohlenstoff in Deutschland. Landbauforschung Völkenrode. p. 71–92.Google Scholar