Retention

Determination of the retention curve / pF-curve, waterrepellency, shrinkage and capillary rise of soil samples.

Retention Measurements

  • Polymer Tensiometer: Measuring matric pressures in soil up to -1.6 MPa. Water filled tensiometers function only up to –0.085 MPa (link to PDF infosheet; 27,4 Kb)
  • Hanging water column:  Determination of water retention characteristic (including hysteresis).
    Pressure head range: from -5 to – 200 cm NEN5786/ISO11274
  • Kaolin box: Determination of water retention characteristic (drying or wetting cycle). NEN5787/ISO11274
  • MAPHSS: Method with Automatically imposed Pressure Heads on Soil Samples. Fully automatic determination of water retention characteristic (including hysteresis).  Pressure head range: from -0.5 to – 600 cm
  • Pressure cells: Determination of water retention characteristic (drying cycle). NEN5788/ISO11274
  • Sand Box: Determination of water retention characteristic (drying or wetting cycle). NEN5787/ISO11274
  • Suction Plate: Determination of water retention characteristic (drying or wetting cycle)
  • Water repellency Alcohol% test: Determination of soil water repellency, making use of increasing alcohol percentages: the higher the alcohol percentage needed to infiltrate a dilution drop in 5 sec. the more water repellent.
  • Water repellency Critical Soil Water Content: Determination of water content below which soil is water repellent and above which it is wettable
  • Water repellency WDPT-test: Quantifying water repellency by determining the Water Drop Penetration Time of 3 water drops on soil samples.
  • Water repellency Wetting Rate: Measurement of the rate of wetting of dry soil samples
  • Evaporation method: Determination of water retention characteristic and unsaturated hydraulic conductivity.
    Pressure head range: from 0 to – 800 cm. NEN5791/ISO11275
  • Multistep: Determination of water retention characteristic and unsaturated hydraulic conductivity.
    Pressure head range: from 0 to – 1000 cm
  • Oxygen profile method: Determination of O2 profiles in soil samples as a function of water content and time
  • Shrinkage Characteristics: Determination of shrinkage by measuring weights and volumes of peat and clay soil samples during evaporation.
  • Capillary rise: Determination of capillary rise given a certain amount of evaporation, using evaporation method.
  • Gravimetrical method: Determination of water content and dry bulk density. NEN5781/ISO11272