Jouquet Pascal auteur aut IRD Podwojewski Pascal auteur aut IRD Bottinelli Nicolas auteur aut IRD Mathieu Jérôme auteur aut IRD Ricoy M. auteur aut IRD Orange Didier auteur aut IRD Tran T. D. auteur aut IRD Valentin Christian auteur aut IRD text journalArticle eng text/pdf born digital access This manuscript focuses on the effects of above-ground earthworm casts on water runoff and soil erosion in steep-slope ecosystems in Northern Vietnam. We investigated the effects of Amynthas khami, an anecic species producing above-ground casts of prominent size, on water infiltration and soil detachment along a land-use intensification gradient: a cultivation of cassava (Mahinot esculenta; CAS), a plantation of Bracharia (Bracharia ruzziziensis; BRA), a fallow (FAL), a fallow after a forest of Eucalyptus sp. (EUC) and a plantation of trees (Acacia mangium and Venicia Montana; FOR). Two scales of studies were considered: (i) at the structure scale (cm(2)), a water runoff simulation was used to differentiate the effects of casts, free biogenic aggregates that previously belong to casts, and free pbysicogenic aggregates; (ii) at the station levels, 1-m(2) plots were used to determine runoff and soil detachment rates during the rainy season in 2005. A. khami was sensitive to land-use management. Earthworm density was low in all the fields (0-1 ind m(-2)). The highest densities were found in EUC and FOR and no individual was found in CAS. As a consequence, soil surface in EUC and FOR was covered with casts and free biogenic aggregates (approximately 22 and 8 kg m(-2), respectively). In FAL and BRA, casts covered the soil only sparsely with < 3 kg m-2. In CAS, soil surface was characterized by free physicogenic aggregates that might be produced by human activity or cridogeic earthworms through tillage (approximately 1 kg m-2). Water runoff simulation clearly showed an enhancement of water infiltration with earthworm casting activity. Water runoff was more decreased with casts (R-2 = 0.26) than free biogenic aggregates (R-2 = 0.49). Conversely, physicogenic aggregates were not associated with higher water infiltration. Analyses of runoff and soil detachment rates during the rainy season underlined that the more land-use type have aggregates on soil surface and the less important is surface runoff (R-2 = 0.922). Conversely, no relation occurred between aggregates and soil detachment rate. While above-ground casting activity decreased surface runoff, they were not involved in soil detachment, and therefore soil erosion. specialized Erosion Earthworms Above-ground casts Land-use change Water runoff Soil detachment 068 074 74 1 13-21 2008 0341-8162 https://www.documentation.ird.fr/hor/fdi:010042679 10.1016/j.catena.2007.12.006 0341-8162 [F B010042679] https://www.documentation.ird.fr/hor/fdi:010042679 https://www.documentation.ird.fr/intranet/publi/2008/08/010042679.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2008-09-19 2017-08-23 fdi:010042679 fre