Isotopic response of run-off to forest disturbance in small mountain catchments

0496470 - BC 2019 RIV GB eng J - Článek v odborném periodiku
Vystavna, Yuliya - Holko, L. - Hejzlar, Josef - Perșoiu, A. - Graham, Neil D. - Juras, R. - Huneau, F. - Gibson, J.
Isotopic response of run-off to forest disturbance in small mountain catchments.
Hydrological Processes. Roč. 32, č. 24 (2018), s. 3650-3661. ISSN 0885-6087. E-ISSN 1099-1085
Grant CEP: GA ČR GA17-15229S
Grant ostatní: IAEA(XE) CRP F31005
Institucionální podpora: RVO:60077344
Klíčová slova: deforestation * deuterium * evaporation * forest canopy * oxygen-18 * Czech Republic
Obor OECD: Water resources
Impakt faktor: 3.189, rok: 2018

Stable water isotopes were applied to trace hydrological processes in an undisturbed (mature spruce forest) and a nearby disturbed (deforested from a bark beetle outbreak) lake catchments in the Czech Republic. Both catchments are situated above 1,000 m a.s.l. within the Sumava National Park and have similar environmental conditions. The isotopic compositions of precipitation, creeks, springs, and lakes were sampled at 3-week intervals over one hydrological year. Water inputs to catchments were derived from isotopically similar local precipitation, whereas run-off was found to have different isotopic signatures. Creeks in the undisturbed catchment had similar to 1 parts per thousand and similar to 7 parts per thousand higher delta O-18 and delta H-2 with similar to 2 parts per thousand lower d-excess than in the disturbed catchment. The d-excess in creeks of the undisturbed catchment was more pronounced, particularly during snowmelt, and highly heterogeneous as compared with the disturbed catchment. Creeks in the undisturbed catchment were mainly fed by precipitation during the warm period (May-October), whereas creeks in the disturbed catchment were mostly fed by precipitation during the cold period (November-April). Estimated mean transit times of creeks and springs were similar to 6 months, except for two creeks in the undisturbed catchment, which had residence times of similar to 1 year. Although evaporation and transpiration fluxes were apparently reduced in the disturbed catchment, transpiration ratios were similar for both catchments. The difference in isotope signatures between catchments was attributed to the altered role of the forest canopy in temporal water distribution, which produced changes in the water cycle, potentially influencing important biogeochemical processes.
Trvalý link: http://hdl.handle.net/11104/0289286