Sampling Device to Extract Intact Cores in Saturated Organic Soils
Journal - Soil Science Society of America Journal
Physical property data on organic soils are lacking due to difficultyin collecting undisturbed samples from these frequently saturatedand weakly consolidated soils. A sampling device was constructedto extract undisturbed cores from saturated organic soils ina forested setting. The sampler consists of a 100-cm-long, 7.6-cm-diam.schedule 40 PVC pipe that was fitted with female threaded adapterson either end. A cutting head was constructed to cut throughthe fibric root mat and other woody debris in the profile bygluing a 7.6-cm-diam. hole-saw to a male threaded adaptor thatwas attached to the PVC pipe. The sampler was rotated by handinto the organic soil with gentle downward pressure. When thedesired depth was reached, the remaining air space in the PVCpipe was filled with water and a threaded cap was used to sealthe top of the sampler. A 1.3-cm-diam. galvanized pipe was insertednext to the sampler to add water to the bottom of the core,relieving the suction created as the core was pulled from thesoil. The sampler and vent pipe were pulled from the soil eitherby hand or with a tripod–winch arrangement. Before thecutting head was raised above the water table, it was removedand replaced with another threaded PVC cap. The 100-cm-longpipe containing the soil core was then cut into 7.6-cm-longsections using a wheel-type PVC pipe cutter. Saturated hydraulicconductivity and soil water characteristics were then measuredin the laboratory using the resulting 7.6-cm-long samples encasedin the PVC cylinders.