
TY  - JOUR
A1  - Talsma, T 
A1  - Gardner, EA 
T1  - Soil water extraction by a mixed eucalypt forest during a drought period
JF  - Soil Research
JO  - Soil Res.
Y1  - 1986
VL  - 24
IS  - 1
SP  - 25
EP  - 32
KW  - 
UR  - https://doi.org/10.1071/SR9860025 
N2  - Eucalypt trees growing on deep soils, with a water table at about 8 m depth, showed no apparent drought effects during the 1982-83 dry period in south-east Australia when gross precipitation was only 388 mm. At the end of the drought, soil water to 4 m depth was depleted to a soil water potential of -0.5 MPa and under these conditions unsaturated flow from the water table to the lower root zone was calculated to be 0.17 mm day-1. Water extraction over the depth interval from 0 to 6 m in the drought year was 533 mm, some 200 mm in excess of that used during a year of average rainfall. The contribution to tree water use from unsaturated flow from the water table was calculated to be small (15 mm) even in a drought year, and in most years water movement would be towards the water table to yield a deep drainage term estimated between 40 and 100 mm. Growth ring studies indicated that the lower water use, estimated at 2.6 mm day-1 during the spring-summer drought, did not affect the slowly growing E. radiata species, but reduced stem diameter growth of the faster growing E. dalrympleana and E. pauciflora species. 
ER  -

