AAG 2009 - Talk

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This is the most recent presentation of current resaerch on channel disturbance in Ozark Rivers.

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  • Recognize the resolution of human-induced disturbance amongst the natural variability of river behavior.
  • Goal is to expand on this from a regional perspectiveNot just classify, but understand the conditions that dictate disturbance formation and evolutionMuch research done on meander migration – flume experiments, great if working in an unbound, homogenous environment….not ozarks
  • During the development of the watershed management plan…….This is possibly a result of the watersheds history……And it could also be a result of the rapid urbanization in the watershed as it contains…….And also noteworthy is that Finley Creek is one of the…….
  • VERY LITTLE CHANGE BETWEEN 1955 AND 2006…..but we can see that sinuosity is the highest in the middle section…..so although one type of disturbance dominates, the degree of disturbance balances out the sinuosity, so let’s look at the degree of change…….
  • We found no such relationship in this Ozarks Stream
  • AAG 2009 - Talk

    1. 1. Analysis and Classification of Channel Disturbance Zones in an Ozark River<br />Derek Martin – Research Specialist<br />Ozarks Environmental and Water Resources Institute (OEWRI)<br />Missouri State University<br />Springfield, Missouri<br />
    2. 2. Channel “Disturbance”<br />“An area where excessive erosion or deposition has taken place, often resulting in extreme changes in channel pattern.”<br /> -Robert Jacobson (USGS)<br />
    3. 3. Importance of identifying and understanding channel disturbance<br />Biological<br />Physical<br />Engineering = Predictive capabilities<br />Channel “Disturbance”<br />
    4. 4. Characteristics of Ozarks River Channels<br />Bedrock bed control<br />High width/depth ratios<br />Induces lateral channel movement where allowed<br />Lateral controls<br />Valley width<br />Bluffs<br />Riparian Veg?<br />Sediment Inputs<br />Cherty gravel<br />Landuse induced?<br />Combine to form unique channel patterns in the Ozarks…….<br />
    5. 5. Channel Pattern Classification<br />Jacobson, 1995<br />
    6. 6. Channel Pattern Classification<br />Channel Pattern Classification History<br />Leopold & Wolman, 1957<br />Brice, 1975<br />Schumm, 1981<br />Nanson and Hickin, 1983<br />Rosgen, 1996<br />Rotation<br />Translation<br />Lobing and Compound Growth<br />Extension<br />
    7. 7. Disturbance Area Analysis – Finley River<br />
    8. 8. Disturbance Area Analysis – Finley River<br />Why Finley River?<br /><ul><li>Stakeholders and managers have identified channel instability and sedimentation as one of the primary problems affecting their watershed
    9. 9. History of agricultural land management
    10. 10. Contains one of the fastest growing counties in Missouri
    11. 11. One of the largest tributaries to the James River, which is on Missouri’s 303(d) list for nutrient impairment……Phosphorus laden sediments</li></li></ul><li>Research Objectives/Questions<br /><ul><li>Determine locations and extent of recent/historical channel change (disturbance zones)
    12. 12. What dictates disturbance area formation?
    13. 13. Characterize relevant channel change disturbance types
    14. 14. Interpret changes within the context of local physiography (Ozarks, Karst)</li></ul>Disturbance Area Analysis – Finley River<br />
    15. 15. Study Area<br />Typical karst topography<br /><ul><li>Limestone
    16. 16. Sinkholes
    17. 17. Springs
    18. 18. Bedrock Control</li></ul>Watershed Statistics<br /><ul><li>266 mi2
    19. 19. Land use
    20. 20. 60% Grassland
    21. 21. 27% Forest
    22. 22. 5% Urban</li></li></ul><li>Methods<br />3. Data Analysis<br />Dist Zone Determination<br />1. Photograph Analysis<br />Dist Zone Classificaton<br />Photo Acquisition<br />Watershed Variables<br />Photo Rectification<br />Sinuostiy<br />Migration Rates<br />Error Analysis<br />Drainage Area<br />Active Channel Width<br />2. Data Extraction/Compilation<br />Confinement Ratio<br />Channel Centerlines<br />Valley Width<br />For Photo Error Buffer<br />For Riparian Landcover Buffer <br />Gravel Bars<br />Riparian Landcover<br />Soils<br />DEM<br />Watershed Delineation<br />Slope Derivation<br />
    23. 23. Methods<br />Aerial photograph acquisition<br />Rectification<br />Accuracy Assessment<br />
    24. 24. Methods<br />3. Data Analysis<br />Dist Zone Determination<br />1. Photograph Analysis<br />Dist Zone Classificaton<br />Photo Acquisition<br />Watershed Variables<br />Photo Rectification<br />Sinuostiy<br />Migration Rates<br />Error Analysis<br />Drainage Area<br />Active Channel Width<br />2. Data Extraction/Compilation<br />Confinement Ratio<br />Channel Centerlines<br />Valley Width<br />For Photo Error Buffer<br />For Riparian Landcover Buffer <br />Gravel Bars<br />Riparian Landcover<br />Soils<br />DEM<br />Watershed Delineation<br />Slope Derivation<br />
    25. 25. Methods<br />Disturbance Area Identification<br />
    26. 26. Methods<br />Riparian Vegetation Extraction<br />
    27. 27. Methods<br />10m DEM<br />Stream Network<br />Slope<br />Sub-watershed Delineation<br />Stream Profile<br />Confining Valley Features<br />
    28. 28. Methods<br />3. Data Analysis<br />Dist Zone Determination<br />1. Photograph Analysis<br />Dist Zone Classificaton<br />Photo Acquisition<br />Watershed Variables<br />Photo Rectification<br />Sinuostiy<br />Migration Rates<br />Error Analysis<br />Drainage Area<br />Active Channel Width<br />2. Data Extraction/Compilation<br />Confinement Ratio<br />Channel Centerlines<br />Valley Width<br />For Photo Error Buffer<br />For Riparian Landcover Buffer <br />Gravel Bars<br />Riparian Landcover<br />Soils<br />DEM<br />Watershed Delineation<br />Slope Derivation<br />
    29. 29. Data analyzed in three sections of watershed<br />Results<br />
    30. 30. Results<br />21% of main stem classified as disturbance<br />
    31. 31. Results – Disturbance vs. Stable<br /><ul><li>No correlationbtw valley width and active channel width
    32. 32. No differencein valley widths at dist. areas vs. stable areas
    33. 33. Active channel widths are higherin stable areas vs. dist. areas </li></li></ul><li>Results – Disturbance vs. Stable<br /><ul><li>No correlationbtw confinement ratio and downstream location
    34. 34. Confinement ratios are higher in dist. areas vs. stable areas</li></li></ul><li>Results – Disturbance vs. Stable<br />
    35. 35. Results - Disturbance Zone Classification<br /><ul><li>Extension
    36. 36. Translation
    37. 37. Chute Cutoff
    38. 38. Megabar
    39. 39. Extension
    40. 40. Translation
    41. 41. Chute Cutoff
    42. 42. Extension
    43. 43. Translation
    44. 44. Chute Cutoff
    45. 45. Megabar
    46. 46. Extension
    47. 47. Translation
    48. 48. Chute Cutoff
    49. 49. Megabar
    50. 50. Extension
    51. 51. Translation
    52. 52. Chute Cutoff
    53. 53. Megabar</li></li></ul><li>Results - Disturbance Occurrences<br />Watershed-scale Disturbance Characteristics<br />21% of mainstem classified as disturbance areas<br />20 chute cutoff occurrences = dominant disturbance<br />13 megabar, 12 Translation, 10 extensions<br />
    54. 54. Results - Sinuosity<br />
    55. 55. Results – Drainage Area<br />
    56. 56. Results - Degree of Disturbance<br />Extensions – cross-valley migration rate (m/yr)<br />Translation – down-valley migration rate (m/yr)<br />Chute Cutoff – stream segment length reduction (m)<br />Megabar – bar width (m)<br />
    57. 57. Results - Degree of Disturbance<br />Extensions<br />Mean migration rate = 1.01 m/yr<br />Median migration rate = .97 m/yr<br />Translations<br />Mean migration rate = 2.65 m/yr<br />Median migration rate = 2.23 m/yr<br />
    58. 58. Results - Degree of Disturbance<br />Chute Cutoff<br />Mean length = 75.3 m<br />Median length = 43.0 m<br />Megabar<br />Mean bar width = 49.5 m<br />Median bar width = 41.0 m<br />
    59. 59. Results - Meander Migration Rates<br />Hooke (1980) obtained a regression equation between migration rate of meander loops and upstream drainage area<br />No such relationship was discovered for Finley Creek…..almost the opposite.<br />
    60. 60. Conclusions<br />Disturbance areas form in areas of high confinement ratios compared to stable areas<br />Riparian vegetation plays no role in disturbance area formation<br />Four distinct disturbance area patterns can be identified on the Finley River<br />Extension<br />Translation<br />Chute Cut-off<br />Megabar formation<br />Contributing drainage area plays no role in development of specific disturbance types<br />Meander migration in the Finley River does not follow typical migration trends<br />Disturbance types increase or decrease in intensity to maintain a sinuous equilibrium<br />
    61. 61. Final Remarks<br />Make accurate predictions of future river behavior<br />“…a need for predictive capability with respect to river planform change.” (Gilvear et al., 2000)<br />“A knowledge of rates and patterns of planform change is also important in understanding habitat diversity in floodplain environments” (Gilvear et al., 2000)<br />Application of GIS in hydrology and watershed science<br />
    62. 62. Thank You!<br /> Questions?<br />Contact:<br />Derek J. Martin, Research Specialist<br />Ozarks Environmental and Water Resources Institute<br />Missouri State University<br />Email: djmartin@missouristate.edu<br />

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