@article{fdi:010040726,
  title = {{U}sing a structural approach to identify relationships between soil and erosion in a semi-humid forested area, {S}outh {I}ndia},
  author = {{B}arbi{\'e}ro, {L}aurent and {P}arate, {H}.{R}. and {D}escloitres, {M}arc and {B}ost, {A}. and {F}urian, {S}. and {K}umar, {M}. {S}. {M}. and {K}umar, {C}. and {B}raun, {J}ean-{J}acques},
  editor = {},
  language = {{ENG}},
  abstract = {{B}iogeochemical and hydrological cycles are currently studied on a small experimental forested watershed (4.5 km(2)) in the semi-humid {S}outh {I}ndia. {T}his paper presents one of the first data referring to the distribution and dynamics of a widespread red soil ({F}erralsols and {C}hromic {L}uvisols) and black soil ({V}ertisols and {V}ertic intergrades) cover, and its possible relationship with the recent development of the erosion process. {T}he soil map was established from the observation of isolated soil profiles and toposequences, and surveys of soil electromagnetic conductivity ({EM}31, {G}eonics {L}td), lithology and vegetation. {T}he distribution of the different parts of the soil cover in relation to each other was used to establish the dynamics and chronological order of formation. {R}esults indicate that both topography and lithology (gneiss and amphibolite) have influenced the distribution of the soils. {A}t the downslope, the following parts of the soil covers were distinguished: i) red soil system, ii) black soil system, iii) bleached horizon at the top of the black soil and iv) bleached sandy saprolite at the base of the black soil. {T}he red soil is currently transforming into black soil and the transformation front is moving upslope. {I}n the bottom part of the slope, the chronology appears to be the following: black soil > bleached horizon at the top of the black soil > streambed > bleached horizon below the black soil. {I}t appears that the development of the drainage network is a recent process, which was guided by the presence of thin black soil with a vertic horizon less than 2 in deep. {T}hree distinctive types of erosional landforms have been identified: 1. rotational slips ({T}ype 1); 2. a seepage erosion ({T}ype 2) at the top of the black soil profile; 3. {A} combination of earthflow and sliding in the non-cohesive saprolite of the gneiss occurs at midslope ({T}ype 3). {T}ypes 1 and 2 erosion are mainly occurring downslope and are always located at the intersection between the streambed and the red soil-black soil contact. {N}eutron probe monitoring, along an area vulnerable to erosion types 1 and 2, indicates that rotational slips are caused by a temporary watertable at the base of the black soil and within the sandy bleached saprolite, which behaves as a plane of weakness. {T}he watertable is induced by the ephemeral watercourse. {E}rosion type 2 is caused by seepage of a perched watertable, which occurs after swelling and closing of the cracks of the vertic clay horizon and within a light textured and bleached horizon at the top of black soil. {T}ype 3 erosion is not related to the red soil-black soil system but is caused by the seasonal seepage of saturated throughflow in the sandy saprolite of the gneiss occurring at midslope.},
  keywords = {erosion ; structural analysis ; electromagnetic induction ; {C}hromic {L}uvisol ; vertisol ; {S}outh {I}ndia},
  booktitle = {},
  journal = {{C}atena},
  volume = {70},
  numero = {3},
  pages = {313--329},
  ISSN = {0341-8162},
  year = {2007},
  DOI = {10.1016/j.catena.2006.10.013},
  URL = {https://www.documentation.ird.fr/hor/fdi:010040726},
}