The importance of organic matter to nutrient processing in headwater stream bottoms of the coastal plain / by Jessi Elizabeth O'Neal.
| Author/creator | O'Neal, Jessi Elizabeth author. |
| Other author | Christian, Robert R. (Robert Raymond), 1947- degree supervisor. |
| Other author | East Carolina University. Department of Biology. |
| Format | Theses and dissertations |
| Production | 2004. |
| Description | viii, 116 leaves : illustrations, maps ; 28 cm |
| Supplemental Content | Access via ScholarShip |
| Subjects |
| Summary | This study focuses on determining the importance of soil organic matter in stream nutrient processing by utilizing a range of stream conditions found in the coastal plain of North Carolina. The objectives of this study were to (1) develop a method to examine the potential for nutrient processing in stream bottom sediments with respect to soil organic matter characteristics, (2) use the method to determine the relative importance of each soil characteristic to nutrient processing, and (3) use the most robust soil characteristics to create equations to predict nutrient processing potential of headwater stream bottoms. The method was successful in distinguishing significant differences in soil characteristics and nutrient exchange rates among 6 stream sites ranging in conditions from a relatively unaltered channel with mature forested riparian zone to a channelized stream surrounded by row-crop agriculture. The differences in soil characteristics (% organic matter, total N, C:N, litter depth, and microbial respiration) among sites reflected how different sources of litter affect quality and quantity of organic matter on the stream bottom. Nutrient exchange rates across sites represented generally uptake of nitrate and phosphate, and release of ammonium by the soils. Correlation between nutrient exchange rates and soil characteristics was used to understand relationships between nutrient processing and the nature of organic matter. NOx exchange rate was most highly correlated with CO₂ production rate, while NH₄+ exchange rate was most highly correlated with TN at the surface (0-2 cm) and CO₂ production rate below the surface (2-4 cm). PO₄3- exchange rate and physical PO₄3- uptake were much more highly correlated with each other than with organic matter influenced soil characteristics. Multiple regression of exchange rates using organic matter characteristics explained only 17-33% of the variance in NOx and exchange rates. Neither PO₄3- exchange rate nor physical PO₄3- uptake produced significant regression with organic matter characteristics at either depth. Despite the low R² values, the equations predicted reasonable estimates of NOx uptake rate compared to values from the literature. The quality and quantity of organic matter on headwater stream bottoms differ by riparian zone condition and help regulate nutrient exchange rates. Although the predictive ability of the equations using soil characteristics remains unclear, the relative importance of soil organic matter characteristics to nutrient processing can be useful in assessment and restoration of headwater streams in the coastal plain. |
| General note | Presented to the faculty of the Department of Biology. |
| General note | Advisor: Robert Christian |
| Dissertation note | M.S. East Carolina University 2004 |
| Bibliography note | Includes bibliographical references (leaves 92-97). |
| Genre/form | Academic theses. |
| Genre/form | Academic theses. |
| Genre/form | Thèses et écrits académiques. |
Availability
| Library | Location | Call Number | Status | Item Actions |
|---|---|---|---|---|
| Joyner | University Archives | ASK AT SPECIAL COLLECTIONS DESK | ✔ Available | Request Material |
| Electronic Resources | Access Content Online | ✔ Available |