Ecohydrological impacts of eucalypt plantations: A review

Eucalyptus plantations were established rapidly over large areas of the world raising concerns over water resources and potentially negative ecohydrological effects. In this paper the impacts of Eucalyptus plantations on ecohydrology were summarized. In general, transpiration rates ranged from 0.5 to 6.0 mm per day and were affected by leaf area index (LAI), soil water, stand age, and species conversion. Catchment water yield increased after deforestation due to clearcutting, thinning, or fire, and declined after afforestation or reforestation. Water yield of catchments declined for the first 20-30 years after planting or regeneration of Eucalyptus as trees matured and closed canopies; water yield returned slowly to normal levels as stem density and LAI of Eucalyptus forests declined. Eucalyptus plantations may extract water from shallow groundwater sources in arid and semi-arid areas, and in some tropical wet areas during drought years or seasons.