| Popis: |
DeBano (1969) defined water repellency in terms of the time required for a drop of water to be absorbed by the soil. If a water droplet fails to penetrate within 5 seconds, the soil is classified as being water repellent. Foggin & DeBano (197 1) have discussed the nature of water repellency in some detail. According to these authors, water repellency is caused by an organic coating on the soil particles. The chemical nature of this organic coating is still unidentified. These authors go on to state that factors affecting water repellency include “. . , the composition of the micro-organic community, the nature of the vegetation, physical characteristics of the soil, and the fire history of the area.” During the course of studies by the Montana Agricultural Experiment Station on sagebrush control, it was noted that the soils immediately under burned sagebrush plants remained bare for 3 years or more. This phenomenon has been observed in several other sagebrush burns. Water repellency was suspected. Two limited studies to test water repellency following burning were conducted. |
