Envco – Environmental Equipment

The Model 1900 Soil Water Sampler has been a standard for over 30 years in near surface environmental, ground water and plant rooting health where soil pore water is required. It's a large-volume sampler designed for near-surface installation at depths ranging from 6 inches (15 cm) to 6 feet (1.8 m). Most commonly used to collect pore water in near surface profiles, for the analysis of nutrients, pollutants, or other dissolved ions that have an effect on ground waters, environment and crop health.

Soilmoisture’s Soil Water Samplers, which are also referred to as “suction lysimeters” or “lysimeters”, have been in general use around the world for many years. Soil water is held largely under a state of tension (negative pressure) within the soil by capillary forces. The capillary force is the sum of the adhesive and cohesive forces. The adhesive force is characterized as the attraction of water for soil solids (soil and organic matter). Cohesive force is characterized as the attraction of water for itself. Adhesive force is far greater than the cohesive force. Water is naturally attracted to soil particles (by its adhesive quality) and “sticks” to the surface of each particle and in the various sized “capillary” spaces or “pores” between the soil particles. When the soil is very wet, the large pores fill with water. This “excess” water has no direct surface contact with the soil and is held cohesively, one water molecule to another, and can move quite freely. As a soil dries out, the “excess” water first evaporates as it requires less energy to break the cohesive bonds. The remaining water, held tightly inside the capillary spaces by adhesive qualities, requires more energy to be removed from the soil.

This tension that determines how moisture moves in the soil is referred to as “soil water tension”, “negative pore pressure”, or “soil suction”. For simplicity’s sake we refer to this tension as “soil suction” in these instructions, but keep in mind that negative pressure is the most descriptive term.

The unit consists of a 1.9” (4.8 cm) outside diameter PVC tube, with a 2 bar (200-kPa) porous cup, Santoprene stopper, and Neoprene access tube used for evacuation. Clamping rings slip over the folded Neoprene tubing to seal the sampler after evacuation. We recommend an extraction kit, model 1900K2 (50ml) or 1900K3 (1liter) required for sample retrieval and you'll need a vacuum pump required to evacuate the sampler. A Model 2005G2 Vacuum Hand Pump and either Model 1900K3 1,000 ml Extraction Kit or Model 1900K2 50 ml Extraction Kit, are often used for routine operation.

Ordering Information
1900L06-B02M2 soil water sampler, 6” Length (15.24cm), 250 ml
1900L12-B02M2 soil water sampler, 12” Length (30.84cm), 500 ml
1900L24-B02M2 soil water sampler, 24” Length (60.96cm), 1000 ml
1900L36-B02M2 soil water sampler, 36” Length (91.44cm), >1000 ml
1900L48-B02M2 soil water sampler, 48” Length (121.92cm), >1000 ml
1900L60-B02M2 soil water sampler, 60” Length (152.4cm), >1000 ml
1900L72-B02M2 soil water sampler, 72” Length (182.88cm), >1000 ml

Accessories
0930W005 Silica Flour, 5 lb. bag
1900K2 Extraction Kit, 50 ml
1900K3 Extraction Kit, 1,000 ml
2005G2 Vacuum Test Hand Pump

Replacement Parts
Z1900-200 Stopper Assembly (Includes stopper, tubes, and 2 clamping rings)