js diatom amherst 2014
TRANSCRIPT
![Page 1: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/1.jpg)
![Page 2: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/2.jpg)
OUTLINE
• Basic diatom biology and methods
• Local example
• Lake El’gygytgyn diatom record
![Page 3: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/3.jpg)
What are Diatoms?
• Unicellular (sometimes forming colonies)
• Siliceous cell walls
• Algae – Class Bacillariophyceae
![Page 4: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/4.jpg)
valve
frustule (complete cell)
![Page 5: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/5.jpg)
Pennate
Centric
monoraphid
araphid
biraphid
![Page 6: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/6.jpg)
Where do they live?
plankton periphyton (benthos)
![Page 7: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/7.jpg)
![Page 8: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/8.jpg)
How do they reproduce?
![Page 9: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/9.jpg)
10μ
Pliocaenicus
Cyclotella
![Page 10: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/10.jpg)
Methods
•Sediment processing
•Light microscopy •Electron microscopy
![Page 11: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/11.jpg)
![Page 12: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/12.jpg)
Diatoms are sensitive to:
•salinity
•ice cover
•pH
•depth
•nutrients
•temperature
Linking diatoms to paleoclimate?
![Page 13: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/13.jpg)
Transfer Function Approach:
Modern Environmental Conditions
Modern DiatomAssemblage+
![Page 14: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/14.jpg)
![Page 15: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/15.jpg)
Transfer Function Approach:
Modern Environmental Conditions
Modern DiatomAssemblage
Species Optima
Core Assemblage
Environmental Reconstruction
+
![Page 16: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/16.jpg)
Summary
•broad distribution, preservation
•diverse and sensitive(+)
•not observed to be temperature sensitive
•taxonomy complex
•taphonomy
(-)
![Page 17: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/17.jpg)
10μ
![Page 18: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/18.jpg)
![Page 19: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/19.jpg)
![Page 20: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/20.jpg)
![Page 21: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/21.jpg)
Unique Diatoms
![Page 22: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/22.jpg)
PlanktonSize
![Page 23: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/23.jpg)
![Page 24: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/24.jpg)
General Patterns
![Page 25: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/25.jpg)
![Page 26: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/26.jpg)
OlderTaxonomic
Shifts
![Page 27: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/27.jpg)
2.94 Ma – lacks ornamentation; valve face fultoportulae near center
3.09 Ma – ring of valve face fultoportulae near margin disrupt areolae pattern
3.21 Ma – ornamentation on valve face
![Page 28: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/28.jpg)
![Page 29: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/29.jpg)
![Page 30: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/30.jpg)
![Page 31: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/31.jpg)
General Patterns
![Page 32: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/32.jpg)
![Page 33: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/33.jpg)
1.103 Ma
![Page 34: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/34.jpg)
1.095 Ma
![Page 35: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/35.jpg)
1.071 Ma
![Page 36: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/36.jpg)
1.060 Ma
![Page 37: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/37.jpg)
1.057 Ma
![Page 38: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/38.jpg)
![Page 39: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/39.jpg)
![Page 40: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/40.jpg)
![Page 41: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/41.jpg)
![Page 42: Js diatom amherst 2014](https://reader038.vdocuments.site/reader038/viewer/2022103020/55ce8d30bb61eb13488b45d8/html5/thumbnails/42.jpg)