UNDISTURBED SOIL-COLUMNS FOR LYSIMETRY: I. COLLECTION, FIELD TESTING, AND CONSTRUCTION

作者：Palmer R E; Meisinger J J^*; Magette W L

来源：Applied Engineering in Agriculture, 2011, 27(3): 379-389.

• Lysimeter
• Intact soil cores
• Undisturbed soil columns
• Solute transport instruments
• Air permeability

Methods to obtain undisturbed soil columns are vital to the study of solute transport in soils. To preserve the natural solute-flow processes, it is important to maintain the soil's structural integrity and eliminate formation of cracks or channels during column collection and transportation. A simple and inexpensive method of excavation and encasement was developed for 41-cm diameter x 100-cm long undisturbed soil columns. A 50:50 mixture of granular bentonite clay and sand was used to successfully seal the soil column along the length and circumference of it's interface with a 42-cm internal diameter x 100-cm long PVC casing. An air permeability test was adapted to analyze the integrity of the intact soil columns both before and after transportation. A steel frame fitted with a shock-absorbing platform was designed to transport the columns, which successfully transported seven of eight soil columns over a distance of 102 km, as confirmed by the air permeability test. The soil columns were fitted with a series of seven large porous-ceramic extractors that were connected to an on-site vacuum system, which converted the soil columns into small lysimeters. Results of this research demonstrate that it is possible to obtain, transport, and evaluate the structural integrity of undisturbed soil columns and to equip them with a tension-drained collection system suitable for solute transport or water quality research.

• 出版日期2011-5