@article{fdi:010075747,
  title = {{M}apping spatial distribution of soil properties using electrical resistivity on a long term sugarcane trial in {S}outh {A}frica},
  author = {{H}ovhannissian, {G}aghik and {P}odwojewski, {P}ascal and {L}e {T}roquer, {Y}ann and {M}thimkhulu, {S}. and {V}an {A}ntwerpen, {R}.},
  editor = {},
  language = {{ENG}},
  abstract = {{I}n experimental trials the spatial distribution of soil properties is a key factor to evaluate and determine the credibility of the research outcomes. {T}o evaluate the spatial distribution of soil properties at different depths in the present study, the electrical resistivity method was selected because of its non-destructive nature and high spatial resolution. {T}he investigation was conducted on {BT}1 ({B}urning versus mulching) the world's oldest sugarcane trial (established 25 {O}ctober 1939) located on the premises of the {S}outh {A}frican {S}ugarcane {R}esearch {I}nstitute ({SASRI}). {T}he experimental area, covering 7200 m(2), is divided in 32 plots with three crop residue retention treatments. {T}hese treatments are either fertilized and not fertilized. {T}he {RM}15 resistance-meter equipped with a multiplexer was used to collect geophysical data. {T}he latter was used to generate apparent electrical resistivity maps corresponding to three approximate depth ranges: (0-0.5 m, 0-1.0 m and 0-2.0 m). {T}he spatial resolution of the shallowest map (0-0.5 m), was 0.5 m x 1.0 m. {B}ulk density and soil water content, for the 0-0.1 m depths, were also determined from samples collected on a grid of 4 m x 5 m. {A}ll data collected were georeferenced using a spatial resolution of 4 m x 1 m with the {D}igital {E}levation {M}odel ({DEM}). {T}he results of this survey showed the effectiveness of geophysical mapping to reveal detailed information regarding soil spatial variability and to understand and establish the relationships between soil fertility and soil physical properties. {D}etailed analysis of these results led to the identification of two different soil types on the trial site: a {M}ollic {C}ambisol in the upper slope of the trial with a depth of < 1.0 m and a deeper {M}ollic {N}itisol in the lower slope. {A}dditionally, close to the southern edge of the site, higher values of electrical resistivity revealed a layer of colluvial deposits, that has not been considered in the past. {T}he relationships between electrical resistivity and investigated soil properties (soil water content, bulk density, aggregate stability and fertilizer) initially seemed paradoxical. {A}lthough there is still a need for further investigations, the current study decently establishes the rather unexpected relationships. {T}he most striking finding was the high resistivity in fertilized plots associated with the application of potassium chloride fertilizer which led to a decreased soil aggregate stability.},
  keywords = {{E}lectrical resistivity mapping ; {S}ugarcane ; {M}ulch ; {F}ertilizer ; {B}ulk density ; {S}oil water content ; {S}oil physical properties ; {L}ong term trial ; {AFRIQUE} {DU} {SUD}},
  booktitle = {},
  journal = {{G}eoderma},
  volume = {349},
  numero = {},
  pages = {56--67},
  ISSN = {0016-7061},
  year = {2019},
  DOI = {10.1016/j.geoderma.2019.04.037},
  URL = {https://www.documentation.ird.fr/hor/fdi:010075747},
}