@article{fdi:010073064,
  title = {{C}hanges in streamflow contributions with increasing spatial scale in {T}hukela basin, {S}outh {A}frica},
  author = {{M}utema, {M}. and {C}haplot, {V}incent},
  editor = {},
  language = {{ENG}},
  abstract = {{S}ustainable management of river basins requires precise understanding of the origin and variability of water fluxes. {W}ater samples were collected in {T}hukela {B}asin (30,000 km(2)), {S}outh {A}frica, over the 2012 rainy season, from fifteen 1 m(2) runoff microplots (for {OF}), a 5-m deep piezometer ({SW}) and 20-m deep borehole ({GW}), in the basin headwater and nested catchment outlets (microcatchment, 0.23 km(2); subcatchment, 1.20 km(2); catchment, 9.75 km(2); sub-basin, 253 km(2)). {T}he water samples were analysed for {S}odium ({N}a) and {S}ilica ({S}i) concentrations using an inductively coupled-plasma emission spectrophotometry. {E}nd {M}ember {M}ixing {A}nalysis ({EMMA}), with {N}a and {S}i as tracers, was then used to quantify the water compartment contributions to river flow. {T}he results showed a general decrease of unit-area runoff in downslope direction from 5.7 to 1.2 {L}m(-2) day(-1) at microplot and microcatchment level, respectively, to 1.4 {L}m(-2) day(-1) at the basin outlet. {OF} contributions averaged 61% at microcatchment, 79% at subcatchment, 40% at catchment, 78% at sub-basin and 67% at the basin outlet, which corresponded to 0.82, 0.26, 5x10(-5), 2x10(-3) and 9x10(-5) {L}m(-2) day(-1), respectively. {T}he respective {SW} contributions were 39% (0.38 {L}m(-2) day(-1)), 18% (0.10 {L}m(-2) day(-1)), 49% (5x10(-5) {L}m(-2) day(-1)), 15% (4x10(-4) {L}m(-2) day(-1)) and 33% (5x10(-5) {L}m(-2) day(-1)). {GW} contributions were much lower at all spatial scales, but showed a general increase with increasing contributing surface area from microcatchment to sub-basin outlet followed by a decrease to the basin outlet. {T}he end-member contributions showed large spatial variations, hence longer-term research integrating more observation points is recommended to generate adequate data for development of prediction models for this important river basin. {M}ore research linking carbon, nutrient and pollutant fluxes to water dynamics is also recommended.},
  keywords = {{H}ydrograph separation ; {EMMA} ; {R}iver basin management ; {S}treamflow contribution ; {W}ater quality ; {AFRIQUE} {DU} {SUD} ; {THUKELA} {BASSIN}},
  booktitle = {},
  journal = {{P}hysics and {C}hemistry of the {E}arth},
  volume = {105},
  numero = {},
  pages = {32--43},
  ISSN = {1474-7065},
  year = {2018},
  DOI = {10.1016/j.pce.2018.02.007},
  URL = {https://www.documentation.ird.fr/hor/fdi:010073064},
}