Record Details
Effects of petroleum mulch on soil water content and soil temperature
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Effects of petroleum mulch on soil water content and soil temperature |
| Names |
Kowsar, Ahang
(creator) Boersma, Larry (advisor) |
| Date Issued | 1968-02-23 (iso8601) |
| Note | Graduation date: 1968 |
| Abstract | Petroleum mulch applied on the soil surface over a row of planted seeds promotes a more rapid and a more uniform germination of seeds, enhances elongation of seedlings and in some cases increases the yield of the crop. The beneficial effects of petroleum mulch have usually been attributed to increased soil temperatures below the mulch. Some reports have pointed out that evaporation of soil water is reduced as a result of the mulch application. An experimental arrangement was designed so that changes in soil temperature and soil water content of mulched and unmulched soil, subjected to the same radiation load could be measured under controlled conditions. Soil at a pre-determined water content was packed into boxes with inside dimensions of 4.0 x 40.0 x 48.0 cm. A ten cm wide band of mulch was applied to one side of the slab leaving 30 cm of bare soil. The soil was subjected to a temperature cycle by turning on infra-red heat lamps at 8:00 A.M., increasing the energy output at hourly intervals with a variable transformer until 2:00 P.M. and then decreasing the energy output until the lights were turned off at 8:00 P.M. Soil temperatures were measured at two-hour intervals with calibrated thermistors inserted into the soil slab. Soil water content changes at selected points were measured at regular intervals with a collimated gamma-beam, movable in a vertical as well as a horizontal direction. The heat flux into the soil was measured with heat flux discs. It was observed that an application of petroleum mulch, changes the temperature and water regime of a soil. The mulch covered soil was about 5°C warmer than the bare soil at the time the soil temperatures attained their maximum value. At all other times the temperature difference between mulched and bare soil was smaller. The bare soil rapidly lost water in the upper four centimeters. The mulch covered soil lost water in the upper cm of soil but gained water at depths below this zone. This gain in water was observed in the zone where seedlings are normally placed, indicating that the beneficial effect of petroleum mulch on germination and seedling growth must be attributed to improved soil water conditions as well as to improved soil temperature conditions. |
| Genre | Thesis/Dissertation |
| Topic | Mulching |
| Identifier | http://hdl.handle.net/1957/47047 |
