| A Watershed Analysis of Long Pond North |
| Colby Environmental Assessment Team | |
| December 7th, 2006 |
| Presentation Outline |
| Long Pond North Watershed Dylan Harrison-Atlas | |
| Historic Trends and Study Objectives Ryan Scott | |
| Water Chemistry Testing Nicole Wong | |
| Land Use Andrew Adelfio | |
| Intermission | |
| Development Patterns K.T. Weber | |
| Water and Phosphorus Budgets Kelly Bakulski | |
| Summary and Recommendations Alex McPherson |
| Long Pond North Watershed |
| Dylan Harrison-Atlas |
| Long Pond |
| Economic, recreational, ecological, and aesthetic value | |
| Boating, swimming, fishing |
| Biological Perspective |
| Native Aquatic Flora | ||
| Oxygenate water column | ||
| Provide food and shelter for aquatic organisms | ||
| Sequester phosphorus | ||
| Biological Perspective |
| Invasive Plants | ||
| Have a competitive advantage over native flora | ||
| Pose a serious threat to lake health and can dominate entire ecosystems | ||
| Introduced primarily through boating | ||
| Biological Perspective Invasive Aquatic Plants Threatening Maine’s Inland Waters |
| Biological Perspective |
| Fish stocking | ||
| Administered by Maine Department of Inland Fisheries and Wildlife (MDIFW) | ||
| MDIFW stocks brook trout and landlocked salmon into Long Pond | ||
| Low dissolved oxygen levels threaten salmonids | ||
Watershed Description |
| Watershed: total land area that contributes a flow of water to a particular basin | |
| Watershed boundary defined by highest points of land that surround a lake and its tributaries |
| Watershed Description |
| Watershed Description |
| Covers more than 6600 acres | |
| Includes wetlands, coniferous and deciduous forests, small ponds, and riparian habitat |
| Slide 12 |
| "Surface area =" |
| Surface area = | |
| 1275 acres | |
| Mean depth = | |
| 10 meters | |
| Maximum depth = | |
| 20 meters |
| Long Pond North and Study Objectives |
| Ryan Scott |
| Overview |
| Current and Historical Trends | |
| Project Objectives |
| Long Pond: Present State |
| Relatively healthy lake | ||
| There are issues threatening its stability | ||
| DO, Transparency, Gloeotrichia | ||
| Transparency |
| Secchi Disk | |
| Indication of lake water quality |
| Trophic State Index |
| Lakes are characterized as oligotrophic, mesotrophic or eutrophic | ||
| Most Maine lakes are mesotrophic | ||
| Trophic State Index |
| Determined using transparency | ||
| Oligotrophic: 0-40 | ||
| Mesotrophic: 40-49 | ||
| Eutrophic: >50 | ||
| In 1978 TSI = 33 | ||
| TSISD = 10[6-(ln SD/ln 2)] | ||
| Mean SD = 4.65 m | ||
| Long Pond TSI = 38 | ||
| Dissolved Oxygen (DO) |
| Measured using YSI DataSonde | ||
| Implications: | ||
| Deep water fisheries | ||
| Algal blooms | ||
| Gloeotrichia |
| Cyanobacteria | ||
| (Blue Green Algae) | ||
| Becoming abundant in Great Pond | ||
| Long Pond experiencing increased abundance | ||
| Gloeotrichia |
| Current Research | ||
| Implications | ||
| Health | ||
| Recreational | ||
| Impaired Lakes |
| Placement by Maine DEP | ||
| Combination of factors | ||
| Study Objectives |
| Water Quality | |
| Land Use | |
| Models | |
| Future Trends |
| Study Objectives |
| Water Quality | ||
| Multitude of tests | ||
| Varied sample sites | ||
| Location | ||
| Sampling techniques | ||
| Study Objectives |
| Land Use | ||
| DOQs to determine land use | ||
| Used for projections, phosphorus budget | ||
| Study Objectives |
| Models | ||
| Used to understand and estimate impact of land | ||
| Septic suitability, erosion potential, phosphorus and water budgets | ||
| Study Objectives |
| Future Trends | ||
| Combination of models and information from town officials | ||
| Crucial in maintaining health of Long Pond | ||
| Water Chemistry Testing |
| Nicole Wong |
| Overview |
| Introduction | ||
| What did we measure? | ||
| Our results | ||
| Conclusions | ||
| Introduction |
| Historically high water quality until recently | |
| 2006 - “Impaired” lake status |
| Sampling Site Locations |
| Parameters |
| Dissolved oxygen (DO) | |
| Phosphorus | |
| Chlorophyll-a | |
| Temperature | |
| pH | |
| Transparency |
| Dissolved Oxygen (DO) |
| Measurement of the amount of O2 dissolved in water | ||
| DO < 5 ppm: dangerous for cold water fish | ||
| DO < 1 ppm: anoxic | ||
| Factors affecting DO: | ||
| decomposition, microbial activity, respiration, turbulence, wind, salinity, temperature | ||
| Dissolved Oxygen (DO) |
| Phosphorus (P) |
| "Mean (± SE)" |
| Mean (± SE) surface, mid, and bottom phosphorus concentrations (ppb) |
| Chlorophyll-a |
| Photosynthetic pigment | ||
| Estimate of relative phytoplankton biomass | ||
| Factors affecting chlorophyll-a concentrations: | ||
| temperature, light, nutrient levels, weather conditions | ||
| Chlorophyll-a |
| Dissolved Oxygen (DO) |
| "Mean (± SE)" |
| Mean (± SE) surface, mid, and bottom phosphorus concentrations (ppb) |
| Temperature |
| Stratification and Turnover |
| Phosphorus (P) |
| pH |
| Measurement of H+ ions | ||
| Typical lakes: 4 to 9 | ||
| Factors that affect pH: | ||
| Decomposition | ||
| Acid Rain | ||
| Primary Production | ||
| pH |
| 2006 pH profiles |
| Transparency |
| Measure of visibility in the water column | |
| Secchi disk and aquascope | |
| Secchi depth < 2 m: algae bloom |
| i.e. Visibility |
| Transparency |
| Transparency |
| Water Chemistry Conclusions |
| The overall water quality of Long Pond North is good | ||
| PREVENTION IS KEY | ||
| Current concerns: | ||
| trends in decreasing Secchi depth | ||
| increasing anoxia | ||
| Land Use |
| Andrew Adelfio |
| Land Use |
| Importance for our study |
| Geographic Information System |
| ArcGIS 9.1® | ||
| A computer system that is capable of doing the following to geographically-referenced information: | ||
| Integrating | ||
| Editing | ||
| Analyzing | ||
| Displaying | ||
| Methods for Designating
Land-Use Categories |
| Digital Orthophoto-Quadrangles (DOQs) | ||
| Obtained from Maine Office of GIS | ||
| Aerial photographs taken between 1-Mar-03 and 19-May-03 | ||
| Land-Use Types |
| Water Body | |
| Wetland | |
| Coniferous Forest | |
| Mixed Forest | |
| Deciduous Forest | |
| Park | |
| Regenerating Land |
| Example of DOQ Interpretation |
| Shoreline Residential |
| Ground-Truthing |
| The use of a ground survey to confirm the findings of an aerial survey | ||
| Learn about areas with: | ||
| Poor resolution | ||
| Confusing texture or color | ||
| Deciduous Forest Ground-Truthing |
| Polygon Creation |
| Slide 61 |
| Current vs. Past Land Use |
| Intermission |