作者: Takanori Shimizu , Tomo’omi Kumagai , Masahiro Kobayashi , Koji Tamai , Shin’ichi Iida
DOI: 10.1016/J.JHYDROL.2014.12.021
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摘要: Summary Evapotranspiration (ET) was estimated from a planted coniferous forest in southwestern Japan by applying three methods: the eddy covariance method; measurement of rainfall ( P ) and runoff Q small watershed; combination interception loss I C ), upper canopy transpiration based on sap-flux density Japanese cedar Cryptomeria Japonica D. Don) stands E UC modeled sub-canopy ET SC ). After inverse multiplication energy imbalance ratio, method (ET EC 839.9 mm 2007 811.8 mm 2008. The yearly values – were partially affected previous autumn. continuous data collection for more than 5 years, became stable. 9-year (2000–2008) average , which considered most reliable this study, 897.5 mm y −1 . cumulative during daylight hours right stream bank, covered mainly with large cedars, 894.1 mm April to March value almost same as that calculated components sum COMP = + : 911.4 mm), comparison suggested annual totals an correction provide estimate stand complex topography. Spatial variation watershed likely caused differences soil water retention at each slope position. slight difference compared 2008 attributed radiative input. In monthly–weekly analysis, frequently higher after heavy rainfall, while under dry conditions active ET. Even conditions, daily often results time-lag evaporation ecosystem and/or under-estimated rainfall.