@article{fdi:010068920,
  title = {{G}roundwater resource vulnerability and spatial variability of nitrate contamination : insights from high density tubewell monitoring in a hard rock aquifer},
  author = {{B}uvaneshwari, {S}. and {R}iotte, {J}ean and {S}ekhar, {M}. and {K}umar, {M}. {S}. {M}. and {S}harma, {A}. {K}. and {D}uprey, {J}. {L}. and {A}udry, {S}. and {G}iriraja, {P}. {R}. and {P}raveenkumarreddy, {Y}. and {M}oger, {H}. and {D}urand, {P}. and {B}raun, {J}ean-{J}acques and {R}uiz, {L}aurent},
  editor = {},
  language = {{ENG}},
  abstract = {{A}griculture has been increasingly relying on groundwater irrigation for the last decades, leading to severe groundwater depletion and/or nitrate contamination. {U}nderstanding the links between nitrate concentration and groundwater resource is a prerequisite for assessing the sustainability of irrigated systems. {T}he {B}erambadi catchment ({ORE}-{BVET}/{K}abini {C}ritical {Z}one {O}bservatory) in {S}outhern {I}ndia is a typical example of intensive irrigated agriculture and then an ideal site to study the relative influences of land use, management practices and aquifer properties on {NO}3 spatial distribution in groundwater. {T}he monitoring of >200 tube wells revealed nitrate concentrations from {I} to 360 mg/{L}. {T}hree configurations of groundwater level and elevation gradient were identified: i) {NO}3 hot spots associated to deep groundwater levels (30-60.m) and low groundwater elevation gradient suggest small groundwater reserve with absence of lateral flow, then degradation of groundwater quality due to recycling through pumping and return flow; ii) high groundwater elevation gradient, moderate {NO}3 concentrations suggest that significant lateral flow prevented {NO}3 enrichment; iii) low {NO}3 concentrations, low groundwater elevation gradient and shallow groundwater indicate a large reserve. {W}e propose that mapping groundwater level and gradient could be used to delineate zones vulnerable to agriculture intensification in catchments where groundwater from low-yielding aquifers is the only source of irrigation. {T}hen, wells located in low groundwater elevation gradient zones are likely to be suitable for assessing the impacts of local agricultural systems, while wells located in zones with high elevation gradient would reflect the average groundwater quality of the catchment, and hence should be used for regional mapping of groundwater quality. {I}rrigatiori with {NO}3 concentrated groundwater induces a "hidden" input of nitrogen to the crop which can reach 200 kg{N}/ha/yr in hotspot areas, enhancing groundwater contamination. {S}uch fluxes, once taken into account in fertilizer management, would allow optimizing fertilizer consumption and mitigate high nitrate concentrations in groundwater.},
  keywords = {{G}roundwater ; {N}itrate pollution ; {A}griculture ; {I}rrigation ; {S}emi-arid ; {I}ndia ; {INDE}},
  booktitle = {},
  journal = {{S}cience of the {T}otal {E}nvironment},
  volume = {579},
  numero = {},
  pages = {838--847},
  ISSN = {0048-9697},
  year = {2017},
  DOI = {10.1016/j.scitotenv.2016.11.017},
  URL = {https://www.documentation.ird.fr/hor/fdi:010068920},
}