Fourteen years of evidence for positive effects of conservation agriculture and organic farming on soil life
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Conventional agriculture strongly alters soil quality due to industrial practices that often have negative effects on soil life. Alternative systems such as conservation agriculture and organic farming could restore better conditions for soil organisms. Improving soil life should in turn improve soil quality and farming sustainability. Here, we have compared for the first time the long-term effects of conservation agriculture, organic farming, and conventional agriculture on major soil organisms such as microbes, nematofauna, and macrofauna. We have also analyzed functional groups. Soils were sampled at the 14-year-old experimental site of La Cage, near Versailles, France. The microbial community was analyzed using molecular biology techniques. Nematofauna and macrofauna were analyzed and classified into functional groups. Our results show that both conservation and organic systems increased the abundance and biomass of all soil organisms, except predaceous nematodes. For example, macrofauna increased from 100 to 2,500 %, nematodes from 100 to 700 %, and microorganisms from 30 to 70 %. Conservation agriculture showed a higher overall improvement than organic farming. Conservation agriculture increased the number of many organisms such as bacteria, fungi, anecic earthworms, and phytophagous and rhizophagous arthropods. Organic farming improved mainly the bacterial pathway of the soil food web and endogeic and anecic earthworms. Overall, our study shows that long-term, no-tillage, and cover crops are better for soil biota than periodic legume green manures, pesticides, and mineral fertilizers.
KeywordsSoil biodiversity Functional groups Soil food web Soil functioning Soil quality Land management Agricultural sustainability Agroecosystems Agroecology
This study was financially supported by the ANR Systerra-PEPITES research program coordinated by Dr. S. de Tourdonnet (IRC—Montpellier SupAgro). We greatly thank O. Ba, J. Thénard, C. Marraud, J.P. Pétraud, N. Cheviron, E. Kouakoua, L. Amenc, E. Tournier, A. Martin, D. Viratel, R. Lefèvre, C. Naisse, and S. Lutfalla for laboratory, technical, and field support. We are also grateful to A. Marmeys, G. Grandeau, and Dr. J.F. Vian for valuable discussions and P. Deleporte, A. Gauffreteau, and Dr. C. Salomé for their advice on statistical issues.
- Bernard L, Mougel C, Maron PA, Nowak V, Leveque J, Henault C, Haichar FEZ, Berge O, Marol C, Balesdent J, Gibiat F, Lemanceau P, Ranjard L (2007) Dynamics and identification of soil microbial populations actively assimilating carbon from C-13-labelled wheat residue as estimated by DNA- and RNA-SIP techniques. Environ Microbiol 9(3):752–764. doi: 10.1111/j.1462-2920.2006.01197.x PubMedCrossRefGoogle Scholar
- Blanchart E, Villenave C, Viallatoux A, Barthes B, Girardin C, Azontonde A, Feller C (2006) Long-term effect of a legume cover crop (Mucuna pruriens var. utilis) on the communities of soil macrofauna and nematofauna, under maize cultivation, in southern Benin. Eur J Soil Biol 42:S136–S144. doi: 10.1016/j.ejsobi.2006.07.018 CrossRefGoogle Scholar
- Bouché MB, Gardner RH (1984) Earthworm functions. VII. Population estimation techniques. Rev Ecol Biol Sols 21:37–63Google Scholar
- De Vries FT, Thébault E, Liiri M, Birkhofer K, Tsiafouli MA, Bjornlund L, Jorgensen HB, Brady MV, Christensen S, de Ruiter PC, d’Hertefeldt T, Frouz J, Hedlund K, Hemerik L, Gera Hol WH, Hotes S, Mortimer SR, Setälä H, Sgardelis SP, Uteseny K, van der Putten WH, Wolters V, Bardgett RD (2013) Soil food web properties explain ecosystem services across European land use systems. PNAS. doi: 10.1073/pnas.1305198110 Google Scholar
- ISO 23611-4 (2007) Soil quality—sampling of soil invertebrates—part 4: sampling, extraction and identification of soil-inhabiting nematodesGoogle Scholar
- Mühling M, Woolven-Allen, Murrell JC, Joint I (2008) Improved group-specific PCR primers for denaturating gradient gel electrophoresis analysis of the genetic diversity of complex microbial community. Int Soc Microb Ecol 2:379–392Google Scholar
- Philippot L, Bru D, Saby NPA, Cuhel J, Arrouays D, Simek M, Hallin S (2009) Spatial patterns of bacterial taxa in nature reflect ecological traits of deep branches of the 16S rRNA bacterial tree. Environ Microb 11:1096–1104Google Scholar
- Vainio EJ, Hantula J (2000) Direct analysis of wood-inhabiting fungi using denaturating gel electrophoresis of amplified ribosomal DNA. Mycol Res 104:927–936Google Scholar
- Vandermeer J (1995) The ecological basis of alternative agriculture. Annual review of Ecology, Evolution, and Systematics 26 (201–224)Google Scholar
- Wardle DA (1995) Impacts of disturbance on detritus food webs in agro-ecosystems of contrasting tillage and weed management practices. In: Begon M, Fitter AH (eds) Advances in ecological research, vol 26. Academic Press, pp 105–185. doi: 10.1016/s0065-2504(08)60065-3