Data of the apparent respiratory quotient measurements in soil and tree stems, February 2017 to January 2019, Odem forest, Israel.

The files contain data of gaseous CO2 and O2 measurements of soil pore space air and headspace air of incubations of bulk-soil samples, roots, and tree stem cores. Samples were collected from Odem forest, northern Israel, located 950 m a.s.l, 33o 13’ N, 35o 45’ E. The climate is Mesic Mediterranean with a mean annual precipitation of 950 mm and summer and winter mean temperature of 21.3º C and 7.3ºC, respectively. Samples from two oak species were collected: the dominant evergreen Quercus calliprinos Webb (about 75% of the woody cover area), and the winter-deciduous Quercus boissieri Reut. (15%). Soil samples were collected underneath the trees. The soil was formed on basaltic bedrock and is classified as Eutric Lithosol in the FAO classification system and as Lithic Xerorthent in the USDA classification system. The soil pH is 6.6 and the organic C content is 10.5%. These data include CO2 and O2 concentrations, fluxes, the apparent respiratory quotient (ARQ), soil temperature, gravimetric soil moisture, and Fe2+ concentrations. The data are the results of seasonal measurements of soil gas, bulk soil, tree stem cores, and roots incubations, and additional experiments testing the links between Fe2+ oxidation, temperature, and soil moisture with ARQ.