Hydraulic Conductivity - Amoozemeter
Parameter to be measured:
Constant head permeameter: Measures infiltration rate within an auger hole up to a depth of 2 m and with extension set up to a depth of 4 m. A constant hydraulic head is kept in the auger hole which must be H/r >= 5 and the infiltration rate will be monitored until steady state flow is attained. Hydraulic conductivity will be calculated with the equation of Glover (Amoozegar, 1989b, 1993)
- Constant head permeameter with reservoir (with combined) Mariotte-bottle
- dissipation unit
- auger drill equipment
- measure tabe or folding meter stick
- datasheets, stop watch, torch for deep holes
- water vessels for supply
- in-situ measurement, no analysis of disturbed soil samples in lab
- measurement in different depths of soil profile
- easily transportable for monitoring at any location
- less water consume
- many pipes and valves - requires practice and understanding to recognise errors, set-up time
- exact geometry of auger hole as specified in the equation is not often realised
- in depth up to 70 cm the measurment is complicated because of controling water level
- soils with high content of gravels and boulders would be problematic because of realsing the correct geometry of the auger hole
What to watch out for:
potential problems with
- hydrophobic soils
- heterogenous water content of soil before measurement
- strong effects from preferential flowpaths
- strong swelling/shrinking of soil
- effects of impermeable layers before stationarity is achieved
- inclined, uneven surfaces
- in loamy and clay soils the augering will smear up the soil pores which will lead to an underestimation of hydraulic conductivity
Projects that used the above equipment:
Other related web sites:
- Amoozegar, A, 1989a. A compact, constant-head permeameter for measuring saturated hydraulic conductivity of the vadose zone, Soil Sci. Soc. Am. J. 53, 1356–1361.
- Amoozegar, A, 1989b. Comparison of the Glover solution with the simultaneous equations approach for measuring hydraulic onductivity, Soil Sci. Soc. Am. J. 53, 1362–1367.
- Amoozegar, A, 1993. Comments on ‘‘Methods for analyzing constanthead well permeameter data’’, Soil Sci. Soc. Am. J. 57, 559– 560.
- Amoozegar, A, 2005. Amoozemeter, in: Lal, R. Encyclopedia of Soil Science, Second Edition.
- Elrick, DE, Reynolds WD, 1992. Methods for analyzing constanthead well permeameter data, Soil Sci. Soc. Am. J. 56, 320– 323.
- Elrick, DE, Reynolds, WD, 1992. Methods for analyzing constanthead well permeameter data, Soil Sci. Soc. Am. J. 56, 320– 323.
- Elsenbeer, H, Newton, BE, Dunne T, de MoraesJM, 1999. Soil hydraulic conductivities of latosols under pasture, forest and teak in Rondonia, Brazil. Hydrol. Process. 13, 1417-1422.
- Sobieraj, JA, Elsenbeer, H, Coelho, RM, Newton, B, 2002, Spatial variability of soil hydraulic conductivity along a ropical rainforest catena, Geoderma 108, 79–90.
- Zigler, AD, Negishi, JN, Sidle, RC, Noguchi, S, Nik, AR, 2006. Impacts of logging disturbance on hillslope saturated hydraulic conductivity in a tropical forest in Peninsular Malaysia. Catena 67, 89 – 104.