Igert ears lacawac workshop on lake sentinels craig williamson miami university
Download
1 / 33

IGERT EARS Lacawac Workshop on Lake Sentinels: Craig Williamson Miami University - PowerPoint PPT Presentation


  • 76 Views
  • Uploaded on
  • Presentation posted in: General

IGERT EARS Lacawac Workshop on Lake Sentinels: Craig Williamson Miami University. Ganguly, A. R., K. Steinhaeuser, D. J. Erickson III, M. Branstetter, E. S. Parish, N. Singh, J. B. Drake, L. Buja, “Higher trends but larger uncertainty and geographic variability in 21st

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha

Download Presentation

IGERT EARS Lacawac Workshop on Lake Sentinels: Craig Williamson Miami University

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


IGERT EARSLacawac Workshop on Lake Sentinels:Craig WilliamsonMiami University


Ganguly, A. R., K. Steinhaeuser, D. J. Erickson III, M. Branstetter, E. S. Parish, N. Singh, J. B. Drake, L. Buja, “Higher trends but larger uncertainty and geographic variability in 21st

century temperature and heat waves”, Proceedings of the National Academy of Sciences of the United States, 10.1073/pnas.0904495106, 2009.


Ganguly, A. R., K. Steinhaeuser, D. J. Erickson III, M. Branstetter, E. S. Parish, N. Singh, J. B. Drake, L. Buja, “Higher trends but larger uncertainty and geographic variability in 21st

century temperature and heat waves”, Proceedings of the National Academy of Sciences of the United States, 10.1073/pnas.0904495106, 2009.


What will the impacts be on water resources and terrestrial ecosystems?How do we begin to address such daunting challenges of environmental change?Where in the complex landscape should we sample for the best information?


Respond to environmental change, and leave signals in the sediments

Lowest point in the landscape

Lakes!


You Need EARS!Environmental Aquatic Resource SensingYou Need GLEON!Global Lake Ecological Observatory NetworkAdvanced sensors to network lakes across continents to look at lake sentinels.


Lakes as Sentinels and Integrators of Environmental Change

What is a lake sentinel?

Any physical, chemical, or biological characteristic

of a lake that responds to environmental forcing

in an informative and quantifiable way.

What is a paleoecological lake integrator?

Historical sentinels in the sediments that

provide information relevant to climate change

over longer time periods


Lakes are not Isolated Ecosystems

  • Photosynthesis by phytoplankton, benthic algae, macrophytes

    • Endogenous C drives lakes towards autotrophy

      = Autochthonous carbon

  • Integral part of watershed

    • Receive runoff, streamflow, groundwater

    • Inputs of fixed C = POM, DOM (measured as DOC)

    • Exogenous C drives lakes towards heterotrophy

      = Allochthonous carbon


Area Receiving Incident Sunlight


DOC Sources to Lakes

Roulet & Moore 2006 Nature 444:283


Leaching of

dissolved

organic matter

from terrestrial

sources “feeds”

fixed C to aquatic

ecosystems


Allochthonous Sources of Fixed Carbon

Vary with plant species


Lake Lacawac

52 hectares

Mesotrophic

DOC ~ 5 mg/l

UV Z1%320nm ~ 0.5 m

Lake Giles

100 hectares

Oligotrophic

DOC ~ 1.5 mg/l

UV Z1%320nm ~ 3-4 m

Pocono Study Lakes


Light decreases with depth. Why?


Usually use a semilog plot for light.The 1% (of surface PAR) depth = Compensation Depth


What causes temperature changes with depth?

Why do light and temperature profiles differ?


Comparing April and September: 1) What are two seasonal changes in temperature? 2) What are the causes of these differences? 3) What are the implications of these differences?


What causes these changes with depth and season?Role of abiotic vs biotic factors, auto- vs. allochthony?Where is the compensation depth?


What does water transparency tell us?Where is the compensation depth?


How did oxygen change since 1990?

Not much change early in year (April)


How did oxygen change since 1990?

3 major types of change late in year (Sept.)


UV Transparency: 14 year trends

July data: Lake Giles,

N.E. Pennsylvania, USA


Increase in Allochthony?


Climate Change?


Reduced Acid Precipitation?


Reduced Acid Precipitation?


What sentinels of environmental change can you find in Lacawac?

  • Environmental Drivers:

  • Energy:

  • - Temperature, wind

  • Mass:

  • Precipitation, particulates,

  • Dissolved substances.

Lake sentinel:

Any physical, chemical, or biological characteristic

of a lake that responds to environmental forcing

in an informative and quantifiable way.


ad
  • Login