An Instrumented Lysimeter System for Monitoring Salt and Water Movement

Abstract

A lysimeter system is described which consists of four continuously weighing lysimeters mounted on a portable platform. The lysimeters, made from low pressure PVC irrigation pipe (1.18 m deep by 0.31 m dia), are placed on a hydraulic weighing system that consists of either a water-tilled rubber pillow or an automotive innertube connected to a water column. The sensitivity of the weighing system is 0.1 kg or an equivalent water depth of 1.4 mm. One bar ceramic cups, placed in the center of the lysimeters at 0.25, 0.50 and 0.75 m from the soil surface, are connected to the outside for soil solution sampling. Eight small bolts symmetrically located around the lysimeter at the same depths as the ceramic cups, serve as "four probe" contacts for electrical conductivity measurements. The cost of each set of four lysimeters in 1978 was about $400.

Sodium adsorption ratio-exchangeable sodium percentage relationships in a high potassium saline-sodic soil

“…Duplicate soil samples were taken from each plot in 0.25 m increments down to 1.0 m before the treatments were applied and again in the falls of 1980, 1981, and 1982. Soils for the lysimeter study were taken from the 0.30 m surface of a high K saline-sodic area near the field site previously described. The instrumented lysimeters were 0.30 m in diameter and 1 m deep (Robbins and Willardson 1980). The treatments were Caa, , CaSO, • 2 H2 O, and Y CaCl2 + Y2 CaSO, • 2 FLO, added at Ca rates equal to the exchangeable Na in the upper 0.5 m of soil.…”

Chemical oxygen demand fate from cottage cheese (acid) whey applied to a sodic soil

“…To monitor weight changes due to irrigation, evapotranspiration, and drainage, each lysimeter had a hydraulic weighing system (Robbins and Willardson 1980). Each lysimeter contained 30 mm of 0.06-mm washed silica sand in the bottom to facilitate drainage.…”

Cottage cheese (acid) whey effects on sodic soil aggregate stability

“…To each lysimeter, 10 L of water was added on day 16 and 28, 5 L on day 34, and 10 L on day 41. Thereafter, on days 48, 55, 62, 69, 76, and 83, water was applied to each lysimeter at a rate of 1.25 times the evapotranspiration measured (Robbins & Willardson, 1980) from that lysimeter. The barley from the control and 25-mm whey treatments, after it died due to poor air and water relations, was harvested on day 85.…”