caa a22 4500 606219196 CHVBK 20210128101117.0 cr unu---uuuuu 210128e20150601xx s 000 0 eng 10.1007/s11104-015-2422-8 doi (NATIONALLICENCE)springer-10.1007/s11104-015-2422-8 Competition with winter crops induces deeper rooting of walnut trees in a Mediterranean alley cropping agroforestry system [Elektronische Daten] [Rémi Cardinael, Zhun Mao, Iván Prieto, Alexia Stokes, Christian Dupraz, John Kim, Christophe Jourdan] Background and aims: Characterising the spatial distribution of tree fine roots (diameter ≤ 2mm) is fundamental for a better understanding of belowground functioning when tree are grown with associated crops in agroforestry systems. Our aim was to compare fine root distributions and orientations in trees grown in an alley cropping agroforestry stand with those in a tree monoculture. Methods: Fieldwork was conducted in two adjacent 17year old hybrid walnut (Juglans regia × nigra L.) stands in southern France: the agroforestry stand was intercropped with durum wheat (Triticum turgidum L. subsp. durum) whereas the tree monoculture had a natural understorey. Root intercepts were mapped to a depth of 150cm on trench walls in both stands, and to a depth of 400cm in the agroforestry stand in order to characterise tree root distribution below the crop's maximum rooting depth. Soil cubes were then extracted to assess three dimensional root orientation and to establish a predictive model of root length densities (RLD) derived from root intersection densities (RID). Results: In the tree monoculture, root mapping demonstrated a very high tree RID in the top 50cm and a slight decrease in RID with increasing soil depth. However, in the agroforestry stand, RID was significantly lower at 50cm, tree roots colonized deeper soil layers and were more vertically oriented. In the agroforestry stand, RID and RLD were greater within the tree row than in the inter-row. Conclusions: Fine roots of intercropped walnut trees grew significantly deeper, indicating a strong plasticity in root distribution. This plasticity reduced direct root competition from the crop, enabling trees to access deeper water tables not available to crop roots. Springer International Publishing Switzerland, 2015 Deep roots nationallicence Intercropping nationallicence Fine roots nationallicence Juglans sp nationallicence Root anisotropy nationallicence Root intersection density nationallicence Root length density nationallicence Root mapping nationallicence Specific root length nationallicence Cardinael Rémi INRA, UMR System, 2 Place Viala, 34060, Montpellier, France aut Mao Zhun IRSTEA, Unité Ecosystèmes Montagnards, Centre de Grenoble, 2 Rue de la Papeterie, 38402, Saint-Martin-d'Hères, France aut Prieto Iván CNRS, CEFE UMR 5175, Université de Montpellier - Université Paul Valéry - EPHE, 1919 Route de Mende, 34293, Montpellier Cedex 5, France aut Stokes Alexia INRA, UMR AMAP, Boulevard de la Lironde, 34398, Montpellier Cedex 5, France aut Dupraz Christian INRA, UMR System, 2 Place Viala, 34060, Montpellier, France aut Kim John INRA, UMR AMAP, Boulevard de la Lironde, 34398, Montpellier Cedex 5, France aut Jourdan Christophe CIRAD, UMR Eco&Sols, 2 Place Viala, 34060, Montpellier, France aut Plant and Soil Springer International Publishing 391/1-2(2015-06-01), 219-235 0032-079X 391:1-2<219 2015 391 11104 https://doi.org/10.1007/s11104-015-2422-8 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s11104-015-2422-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Cardinael Rémi INRA, UMR System, 2 Place Viala, 34060, Montpellier, France aut NATIONALLICENCE 700 1- Mao Zhun IRSTEA, Unité Ecosystèmes Montagnards, Centre de Grenoble, 2 Rue de la Papeterie, 38402, Saint-Martin-d'Hères, France aut NATIONALLICENCE 700 1- Prieto Iván CNRS, CEFE UMR 5175, Université de Montpellier - Université Paul Valéry - EPHE, 1919 Route de Mende, 34293, Montpellier Cedex 5, France aut NATIONALLICENCE 700 1- Stokes Alexia INRA, UMR AMAP, Boulevard de la Lironde, 34398, Montpellier Cedex 5, France aut NATIONALLICENCE 700 1- Dupraz Christian INRA, UMR System, 2 Place Viala, 34060, Montpellier, France aut NATIONALLICENCE 700 1- Kim John INRA, UMR AMAP, Boulevard de la Lironde, 34398, Montpellier Cedex 5, France aut NATIONALLICENCE 700 1- Jourdan Christophe CIRAD, UMR Eco&Sols, 2 Place Viala, 34060, Montpellier, France aut NATIONALLICENCE 773 0- Plant and Soil Springer International Publishing 391/1-2(2015-06-01), 219-235 0032-079X 391:1-2<219 2015 391 11104