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Chlorophyll and Phytoplankton in Lakes

Chlorophyll and Phytoplankton in Lakes. Emily DeBolt Josh Conway. Chlorophyll and phytoplankton tell the story of lake productivity. Why study chlorophyll and plankton How to collect data Interpreting data from local lakes. Why study chlorophyll and plankton.

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Chlorophyll and Phytoplankton in Lakes

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  1. Chlorophyll and Phytoplankton in Lakes Emily DeBolt Josh Conway

  2. Chlorophyll and phytoplankton tell the story of lake productivity. • Why study chlorophyll and plankton • How to collect data • Interpreting data from local lakes

  3. Why study chlorophyll and plankton • Lake productivity depends on basin morphology, light, nutrients, temperature, etc. • determines biota present

  4. How to collect chlorophyll data • All phytoplankton have chlorophyll • Chlorophyll values are used to estimate phytoplankton biomass and its potential photosynthetic capacity • Microscopic cell counts would be best – but too time consuming • A spectrophotometer is used to measure the total chlorophyll absorption in the water column.

  5. How to collect chlorophyll data • In the lab: • Filtered 250 ml of water from each sample, • and ran through spectrophotometer in 10 ml samples. • So when working with chlorophyll values from lab, • had to divide values by 25 to account for the • concentration of water filtered

  6. How to collect phytoplankton data • In the field: • Kimmerer bottle with marked line and messenger • Sample water at epilimnion, metalimnion, and hypolimnion • Fill 1 liter bottle for each sample • Lugols preservative in each sample • In the lab: • Counted the number of phytoplankton present in each • sample. • (note: phytoplankton counts are from 2004)

  7. Interpreting data from local lakes Rich Lake Arbutus Lake Onondaga Catlin Oneida Green

  8. Oneida Lake

  9. Oneida Lake 73% Chrysophyta (Bacillariophyceae) Melosira Cyclotella Ulothrix Stephanodiscus Aviacosira Stictodiscus 18% Chlorophyta unknown Scenedesmus 9% Cyanophyta Romeria

  10. Oneida Lake Most chlorophyll in the hypolimnion ??

  11. Oneida Lake Parameters: epi: 1mhypo: 8m SA: 207 km2 Eutrophic, Dimictic Mean depth: 6.8 m Max depth: 16.8 m Length: 20.9 mi Width: 5.8 mi • Highest chlorophyll values in hypo!! • Most common phyto are diatoms (which are traditionally more common in early summer) • Light makes it all the way to the bottom – so plankton can live there in this lake!

  12. Rich Lake

  13. Rich Lake 48% 34% Chlorophyta Cyanophyta Cladophora Anabaena Closterium Merismopedia Oscillatoria Spirulina Micricystis 18% Crysophyta (Bacillariophyceae) Cyclotella Melosira Stephanodiscus

  14. Rich Lake phytoplankton • Cosmarium: desmids which are tolerant of acidic conditions • Microsystis: BG that is common blooming nuisance • Oscillatoria: indicator of beginning eutrophism

  15. Rich Lake Values only for epi and meta obtained

  16. Rich Lake Epi: 1m Meta: 6m Hypo: 11m Mostly greens and blue-greens - not sure why… All chlorophyll < 1 ug/L so possibly an oligotrophic lake Note Oscillatoria presence!!

  17. Catlin Lake

  18. Catlin Lake 50% Chlorophyta Gonatozygon Eudorina 50% Chrysophyta LGR Synura

  19. Catlin Lake Phytoplankton mostly in epilimnion

  20. Catlin Lake • We have no additional info on Catlin… • Since there is no BG, I would guess it is oligotrophic

  21. Onondaga Lake

  22. Onondaga Lake 64% Chlorophyta Pandorina unknown Oedogonium Pediastrum Protococcus Scenedesmus Gleocapsa 4% Euglenophyta Euglena 8% Pyrophyta (dinoflagellates) Peridinium 24% Cyanophyta Romeria Microcystis Aphanocapsa LGR

  23. Onondaga Lake Chlorophyll decreases with depth Highest chlorophyll values!

  24. Onondaga Lake Epi: 1m Meta: 12m Hypo: 14m Polluted – excess phosphorous and anoxic hypo Green algae most dominant, but also some BG which makes sense bc Onondaga has highest phosphorous of any of the lakes by far (all other lakes < 2 uM, Onondaga almost 15 uM) Calanoid copepods were most common in all lakes except Onondaga – where Daphnia were most abundant – Daphnia do well with good quality food which might make sense with the high green algae levels

  25. Arbutus Lake

  26. 20% Chrysophyta (Bacillariophyceae) Navicula Melosira Nitzestia Tabellaria 10% Chrysophyta (Chrysophyceae) Synura Dinobrium Arbutus Lake 23 % Chlorophyta Cladophora Unknown Scenedesmus 14% Cyanophyta Unknown Spirulina 23% Pyrophyta Ceratium Peridinium 5% Euglenophyta Euglena 5% Cryptophytas Cryptomonas

  27. Arbutus Lake Phytoplankton are hanging out at the metalimnion

  28. Arbutus Lake Most phytoplankton diversity of all the lakes Epi: 1m Meta: 6m Hypo: 7m Secchi disk at 3 m, so not sure why most phyto would be down at 6 m (think critical mixing depth) Ceratium Spirulina Euglena Cryptomonas

  29. Green Lake The only phytoplankton present: Chlorophyta: Pediastrum

  30. Green Lake Secchi disk at 9m – so good visibility in the lake Epi: 1m Meta: 11m Hypo: 15m Chemo: 19m Monomo: 35m Highest chlorophyll values at chemocline – must be reading chlorophyll from the purple sulfur bacteria Hardwater, meromicitc lake, 52 m deep, very oligotrphic

  31. All lakes chlorophyll values Onondaga has highest values, Deer has lowest No real consistent patterns…

  32. Chlorophyll from the multiprobe

  33. Chlorophyll from the multiprobe

  34. Comparison of multiprobe and spectrophotometer data

  35. Comparison of Lake Depths at Layers

  36. Comparison of Epilimnion chlorophyll data

  37. Comparison of Metalimnion chlorophyll data

  38. Comparison of Hypolimnion chlorophyll data

  39. What does it all mean?(chlorophyll values) • Seemed to get more chlorophyll in hypolimnion than we would have thought • Bad sampling? Or serious lake mixing?

  40. What does it all mean?(phytoplankton) • In general the pattern throughout the year goes: • Diatoms (spring) • Greens (summer) • Blue –greens (late summer) • Dinoflagellates (winter) • With blue-greens dominating in late summer • But we did not really see this – we had mostly greens

  41. What does it all mean? Lake: dominant phyto: trophic state (?) • Oneida: diatoms (E) • Rich: greens (O) • Catlin: greens and goldens (O) • Onondaga: greens (E) • Arbutus: very diverse! (O) • Green: greens (O)

  42. Average Light Coefficients (K) 7 6 5 4 K 3 2 1 0 Oneida Green Deer Arbutus Onondaga Rich Lake What does it all mean? Green had deepest light – but both Green and Oneida had highest light coefficients (odd bc Green is oligotrphic and Oneida is eutrophic… zebra mussels maybe…)

  43. Does more light mean more chlorophyll?

  44. Arbutus and Onondaga had highest chlorophyll values • Onondaga also had highest phosphorous values • But Arbutus had low values!

  45. So if more light doesn’t mean more chlorophyll and more phosphorous doesn’t mean more chlorophyll then what does!!

  46. When did we sample? ADK lakes: Sept 9-11 Onedia: Sept 21-22 Onondaga: Sept 28-29 Green: Oct 5-6 Would have thought possibly lakes visited later more mixed and lakes visited earlier still stratified…

  47. Oneida and Deer have mixed – the rest are still stratified

  48. Controls of Phytoplankton Growth Phytoplankton growth affected by temperature, light Nutrients. Right before FT is a good time for them – But after turnover is not so good - although sometimes Turnover actually increases nutrients so there is a bloom. Since we found so many algae in hypo layer – does that meanall lakes were mixed? This doesn’t appear to be true basedon the temp data…

  49. What was missing and what were our errors? • Counting phytoplankton in lab did not work very well! • Problems with identification • Problems with preservation of phytoplankton?? • Collection of water and data from the lakes

  50. Images satellite de Saint-Pierre et Miquelon (off New Brunswick, Canada) Phytoplankton blooms

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