@article{fdi:010077131,
  title = {{M}ulti-species test and calibration of an improved transient thermal dissipation system of sap flow measurement with a single probe},
  author = {{N}hean, {S}. and {A}yutthaya, {S}. {I}. {N}. and {R}ocheteau, {A}lain and {D}o, {F}r{\'e}d{\'e}ric},
  editor = {},
  language = {{ENG}},
  abstract = {{T}ransient thermal dissipation ({TTD}) systems provide a simple way to measure xylem sap flow with dual or single {G}ranier-type probe, which gives lower energy consumption and higher accuracy due to its lessor sensitivity to thermal interferences. {A} new system, {TTD} heat within 5 min ({TTD}5), proposed on the reduction of the heating duration. {T}his evolution captured interest through decreased energy consumption and increased temporal resolution. {W}ithin our study, the first objective was to test and calibrate this new system with a single probe for young rubber tree - {H}evea brasiliensis. {T}he second objective was to explore the sources of variability in calibration such as species, individual cut-stems and probe-wood contact. {T}he complementary species consisted of two diffuse-porous species (mango tree - {M}angifera indica, eucalyptus tree - {E}ucalyptus camaldulensis) and one ring-porous species (teak tree - {T}ectonia grandis). {T}wenty-eight response curves were assessed over a large range of flux densities from 0.5 to 10 l dm(-2) h(-1). {T}he incremental rise of temperature from 30 to 300 s ({T}300-30) after commencement of heating was sensitive to flux density over the complete range. {C}ompared with the full signal at 300 s, the incremental signal markedly reduced the variability between response curves within species and between species. {M}oreover, a new index {K}-2, defined as ({T}-0 - {T}-u)/{T}-0, normalized the responses between 0 and 1. {H}owever, the responses had a non-linear trend above 5 l dm(-2) h(-1). {W}ithin diffuse-porous wood type, the species did not differ in calibration, whereas the ring-porous species was markedly different. {A} sigmoid function provided the best fit for the diffuse-porous species. {I}ndividual stems were identified as the main source of within-species variability in calibration. {T}he normalizing {K}-2 index removed the influence of probe-wood contacts, controlled through drilling difference; however, there was still an effect of individual stems interacting with flux density ({P} = 0.019). {R}eplications of cut-stems and response curves are necessary to assess a reliable averaged calibration. {I}n conclusion, the applicability of the {TTD}5 system with a single probe has been confirmed and several sources of variability in calibration have been evaluated.},
  keywords = {cut-stem calibration ; {E}ucalyptus camaldulensis ; {H}evea brasiliensis ; {M}angifera indica ; single probe ; {T}ectonia grandis ; {TTD}5 system},
  booktitle = {},
  journal = {{T}ree {P}hysiology},
  volume = {39},
  numero = {6},
  pages = {1061--1070},
  ISSN = {0829-318{X}},
  year = {2019},
  DOI = {10.1093/treephys/tpz017},
  URL = {https://www.documentation.ird.fr/hor/fdi:010077131},
}