Monthly, seasonal and annual water balances of Eucalyptus urophylla plantations on Leizhou Peninsula, Guangdong province, China have been estimated at two sites with contrasting soil types. The Jijia site is on basalt-derived clay-rich soils, while the Hetou site is characterised by coarse-textured soils formed on Quaternary sediments. Observations of evaporative processes (overstorey canopy interception and transpiration, and soil evaporation), soil moisture dynamics, and climate variables were collected at both sites over 2 years. Annual rainfall was 1525 mm and 1918 mm at Jijia, and 1555 mm and 2226 mm at Hetou. Total annual evapotranspiration (ET) was measured as 1079 mm and estimated as 1037 mm at Jijia, and measured as 1033 mrn and estimated as 1104 mm at Hetou during years 1 and 2, respectively, despite 20-30% higher rainfall in year 2. ET at Jijia comprised 548 mm and 518 mm transpiration (T), 285 mm and 208 mm soil evaporation (Es), and 247 mm and 311 mm canopy interception (I) for years 1and 2, respectively. At Hetou, T was 546 mm and 498 mm, Es was 177 mm and 169 mm, and I was 306 mm and 437 mm. Surface and sub-surface drainage was 396 mm and 1007 mm at Jijia, and 538 mm and 1090 mm at Hetou. The higher rainfall in year 2 was estimatedto increase drainage rather than tree water use. Dry season water balances showed ET approached or exceeded rainfall, indicating water use from deep soil storages following shallower soil water depletion. However, storages were replenished by high wet-season drainage. The water use of the eucalypts does not appear to be deleterious for water supply in this area. Differences in soil properties between the sites resulted in a three-fold greater soil water store at Jijia that provided a supply for Es, and the sandier Hetou soils with poor water-holding capacity had greater wet season drainage and higher dry season abstraction from deep storages.
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