{"DOI":"10.5194/hess-2020-648","abstract":"Abstract. Soil evaporation is a key process in the water cycle and can be conveniently quantified with \u03b42H and \u03b418O in bulk surface soil water (BW). However, recent research shows that larger soil pore water evaporates first and differs from small pore water in \u03b42H and \u03b418O, which disqualifies quantification of evaporation from BW \u03b42H and \u03b418O. We hypothesize that BW has different isotopic compositions than evaporating water (EW). Therefore, our objectives are to test the hypothesis, and to evaluate if the difference alters the calculated evaporative water loss. We measured isotopic composition in soil water in two continuous evaporation periods in a summer maize field. Period \u2160 had a duration of 32 days following a precipitation event and Period \u2161 lasted 24 days following an irrigation event with a 2H-enriched water. BW was obtained by cryogenically extracting water from samples of 0\u20135\u2009cm soil taken every three days; EW was derived from condensation water collected every two days on plastic film placed on soil surface. Results showed that when newly added water was heavier than pre-event BW, \u03b42H of BW in Period \u2161 decreased with the increase of evaporation time, indicating evaporation of heavy water; when newly added water was lighter than pre-event BW, \u03b42H and \u03b418O of BW in Period \u2160 and \u03b418O of BW in Period \u2161 increased with increasing evaporation time, suggesting evaporation of light water. Moreover, relative to BW, EW had significantly smaller \u03b42H and \u03b418O in Period \u2160 and significantly smaller \u03b418O in Period \u2161 (p\u2009\u20090.05). Our results have important implication for quantifying evaporation process with water stable isotopes.\n ","author":[{"family":"Wang","given":"Hongxiu"},{"family":"Jin","given":"Jingjing"},{"family":"Si","given":"Bingcheng"},{"family":"Ma","given":"Xiaojun"},{"family":"Wen","given":"Mingyi"}],"id":"unknown","issued":{"date-parts":[[2021,1,26]]},"publisher":"Copernicus GmbH","title":"Technical note: Evaporating water is different from bulk soil water in \u03b42H and \u03b418O","type":"post"}