Record Details
Iron and manganese distribution and seasonal oxidation changes in soils of the Willamette drainage sequence
ScholarsArchive at Oregon State University
| Field | Value |
|---|---|
| Title | Iron and manganese distribution and seasonal oxidation changes in soils of the Willamette drainage sequence |
| Names |
Somera, Rosa Duro
(creator) Simonson, G. H. (advisor) |
| Date Issued | 1967-05-08 (iso8601) |
| Note | Graduation date: 1967 |
| Abstract | This study was conducted to investigate the differences of the profile distribution of free iron and free manganese and the reduction-oxidation changes in soils of the Willamette drainage sequence. Based on the results of the chemical analyses, free iron and free manganese distributions in these soils were governed to a large extent by drainage conditions. In poorly drained soils, free iron content in the upper layers was less compared to the well drained soils. In all drainage classes free iron tended to increase with depth. Free manganese distribution followed no pronounced pattern but in general it decreased with depth. Accumulation of free manganese at the A2 horizons of the poorly drained soils was apparent. Ferrous iron content increased from fall to winter season and then gradually decreased again towards spring and summer months. This observation seems to be in parallel with the water table fluctuations. A marked change was observed in the upper horizons with very slight, if any, in the lower depths. Redox potentials were higher in the better drained soils than those of the poorly drained soils. Consistently positive values in the lower depths were observed which seem to parallel the ferrous iron content. The poorly drained soils contained a greater abundance of iron-manganese concretions than the well drained soils. These concretions were found mostly concentrated in the lower A horizons. Chemical analyses showed that the free iron content was much higher than the free manganese of the concretions. |
| Genre | Thesis/Dissertation |
| Topic | Soils -- Oregon -- Willamette River Valley |
| Identifier | http://hdl.handle.net/1957/47296 |
