Do water isotopes reflect differences in timber harvest practices? Isotope ecohydrology in the Mica Creek watershed, Idaho, USA

The impacts of timber harvesting techniques on the water balance and flow regime were studied at the catchment scale at the Mica Creek Experimental Watershed (97 km2, 975 - 1,750 m a.s.l.) in northwestern Idaho, USA. These studies relied on stable isotopic techniques to assess the variation in water isotope fluxes of clear-cut, partial-cut (thinned), and unimpacted forest sites. Precipitation, stream flow, soil water, and sap flow, and stable isotope concentrations (deuterium and oxygen-18) of these components were measured on a monthly basis starting in fall 2004. The isotopic composition of sap flow appeared to reflect differential canopy interception losses, with greater enrichment under the densest canopies. (author)