Record Details
Survival of fecal coliform bacteria in sludge-amended soils
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Survival of fecal coliform bacteria in sludge-amended soils |
| Names |
Hartel, Peter G.
(creator) Seidler, Ramon J. (advisor) |
| Date Issued | 1983-05-18 (iso8601) |
| Note | Graduation date: 1984 |
| Abstract | A study was conducted to determine the effects or temperature, solar radiation, rainfall, and saturated flow on fecal coliform numbers in sewage sludge-amended soils. To determine this, four 4.6 X 13.7 m field plots were each amended in summer and in winter with 800 liters of anaerobically-digested sewage sludge, and fecal coliform numbers monitored. In winter and in summer, fecal coliform numbers declined from 10⁵ to <10² and <10³ cells/g of soil, respectively, in 13 weeks. In winter, saturated flow conditions accelerated fecal coliform decline by causing movement of the bacterial cells into the soil and groundwater. Under nonsaturated conditions, fecal coliform growth after a rainfall was observed for both sampling periods. Results suggest that growth was dependent on nutrient availability as well as moisture. The effects of solar radiation and temperature could not be determined in winter because of fecal coliform losses to saturated flow, however their effect during the summer was slight. No differences in the die-off rate constants among the four field sites in winter and in summer were observed. The results suggest that movement of fecal coliforms during conditions of saturated flow should be considered in landspreading of sludge. In a separate study, the effect of sludge crusting was studied. The formation of a sludge crust on a Dayton silt loam caused fecal coliform numbers in the 0-2.5 cm soil depth to remain at a constant 10³ cells/g of soil for 11 weeks while numbers in the sludge crust declined from 10⁵ to 10³ cells/g of soil during the same period. The results suggest that the sludge crust serves either as a continuing source of nutrients or fecal coliforms or both for the soil below. A most-probable-number (MPN) microtitration technique for isolating fecal coliforms from soil was developed. A correlation coefficient of 0.86 was obtained when this technique was compared to the standard elevated-temperature fecal coliform MPN procedure. The advantages of this microtechnique are a substantial savings in time and media. |
| Genre | Thesis/Dissertation |
| Topic | Soil microbiology |
| Identifier | http://hdl.handle.net/1957/41626 |
