1. Crop traits drive soil carbon sequestration under organic farming
- Author
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Andreas Gattinger, Nicolas Legay, Rubén Milla, Filipa Reis, Helena Castro, Laura B. Martínez-García, Eduardo Nascimento, Gerlinde B. De Deyn, Pablo García-Palacios, Jean-Christophe Clément, Martina Lori, Tina D'Hertefeldt, Paul Mäder, Sarah Symanczik, Lijbert Brussaard, José Paulo Sousa, Sandra Lavorel, Arnaud Foulquier, Katarina Hedlund, Pedro Martins da Silva, Adrian Müller, Helene Bracht-Jørgensen, Filipe Carvalho, Universidad Rey Juan Carlos [Madrid] (URJC), Research Institute of Organic Agriculture - Forschungsinstitut für biologischen Landbau (FiBL), Lund University [Lund], Wageningen University and Research [Wageningen] (WUR), Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Universidade de Coimbra [Coimbra], Centre Alpin de Recherche sur les Réseaux Trophiques et Ecosystèmes Limniques (CARRTEL), Institut National de la Recherche Agronomique (INRA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Laboratoire d'Ecologie Alpine (LECA ), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Cités, Territoires, Environnement et Sociétés (CITERES), Centre National de la Recherche Scientifique (CNRS)-Université de Tours, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), ECO-SERVE BiodivERsA/001/2014, BiodivERsA/FACCE-JPI BiodivERsA/001/2014, ANR, NWO, FCT, MINECO, FORMAS, SNSF Spanish MINECO, NWO-ALW 864.11.003, Centre National de la Recherche Scientifique (CNRS)-Université de Tours (UT), Research Institute of Organic Agriculture (FiBL), Wageningen University and Research Centre [Wageningen] (WUR), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut National de la Recherche Agronomique (INRA), Laboratoire d'Ecologie Alpine (LECA), Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Université Joseph Fourier - Grenoble 1 (UJF)-Université Grenoble Alpes (UGA), Université de Tours-Centre National de la Recherche Scientifique (CNRS), and Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)
- Subjects
0106 biological sciences ,Crop residue ,[SDV.SA.SDS]Life Sciences [q-bio]/Agricultural sciences/Soil study ,010603 evolutionary biology ,01 natural sciences ,Soil quality ,climate change mitigation ,Soil respiration ,ecological intensification ,organic farming ,soil carbon stocks ,"Organics" in general ,Bodembiologie ,2. Zero hunger ,Topsoil ,Ecology ,leaf nitrogen ,Intensive farming ,fungi ,food and beverages ,04 agricultural and veterinary sciences ,Soil Biology ,15. Life on land ,Plant litter ,PE&RC ,resource economics traits ,Manure ,[SDE.ES]Environmental Sciences/Environmental and Society ,meta-analysis ,Agronomy ,13. Climate action ,crop residue ,040103 agronomy & agriculture ,Organic farming ,0401 agriculture, forestry, and fisheries ,Environmental science ,sense organs ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology - Abstract
1. Organic farming (OF) enhances top soil organic carbon (SOC) stocks in croplands compared with conventional farming (CF), which can contribute to sequester C. As farming system differences in the amount of C inputs to soil (e.g. fertilization and crop residues) are not enough to explain such increase, shifts in crop residue traits important for soil C losses such as litter decomposition may also play a role. 2. To assess whether crop residue (leaf and root) traits determined SOC sequestration responses to OF, we coupled a global meta-analysis with field measurements across a European-wide network of sites. In the meta-analysis, we related crop species averages of leaf N, leaf-dry matter content, fine-root C and N, with SOC stocks and sequestration responses in OF vs. CF. Across six European sites, we measured the management-induced changes in SOC stocks and leaf litter traits after long-term ecological intensive (e.g. OF) vs. CF comparisons. 3. Our global meta-analysis showed that the positive OF-effects on soil respiration, SOC stocks, and SOC sequestration rates were significant even in organic farms with low manure application rates. Although fertilization intensity was the main driver of OF-effects on SOC, leaf and root N concentrations also played a significant role. Across the six European sites, changes towards higher leaf litter N in CF also promoted lower SOC stocks. 4. Our results highlight that crop species displaying traits indicative of resource-acquisitive strategies (e.g. high leaf and root N) increase the difference in SOC between OF and CF. Indeed, changes towards higher crop residue decomposability was related with decreased SOC stocks under CF across European sites. 5. Synthesis and applications. Our study emphasizes that, with management, changes in crop residue traits contribute to the positive effects of organic farming (OF) on soil carbon sequestration. These results provide a clear message to land managers: the choice of crop species, and more importantly their functional traits (e.g. leave and root nitrogen), should be considered in addition to management practices and climate, when evaluating the potential of OF for climate change mitigation.
- Published
- 2018