quaternary environments quaternary ecology. paleoecological studies cannot establish experiments...
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Quaternary EnvironmentsQuaternary EnvironmentsQuaternary EcologyQuaternary Ecology
Paleoecological StudiesPaleoecological Studies
Cannot establish experiments and Cannot establish experiments and replicate themreplicate them
Look for evidence of events that occurred Look for evidence of events that occurred through time and use these “natural through time and use these “natural experiments” of the past to generate experiments” of the past to generate hypotheseshypotheses
Substitution of Space for TimeSubstitution of Space for Time
Pollen AnalysisPollen Analysis
One of our best records of vegetation One of our best records of vegetation assemblages assemblages
Allows us to test hypothesesAllows us to test hypotheses
Venn Diagrams of Analogue Venn Diagrams of Analogue SituationsSituations
Detrended Correspondence Analysis (DCA) of Detrended Correspondence Analysis (DCA) of Forest Communities of Eastern North AmericaForest Communities of Eastern North America
Tauber’s Model of Pollen Transport in a Forested Landscape Where: Cg – Gravity, Ct – Trunk Space, Cc – Canopy, Cr – Rain, Cw – Flowing Water
Bradshaw’s model for the relationship between the diameter of the pollen catchment and its pollen source area.
Scale IssuesScale Issues
In any ecological or paleoecological study, In any ecological or paleoecological study, the organism or population is best viewed the organism or population is best viewed in a context of its life span, life history in a context of its life span, life history strategy, recurrence interval and strategy, recurrence interval and magnitude of disturbancesmagnitude of disturbances
Spatial and Temporal Domains for a Hierarchical Spatial and Temporal Domains for a Hierarchical Characterization of Environmental Forcing FactorsCharacterization of Environmental Forcing Factors
Environmental Disturbance Regimes, Biotic Environmental Disturbance Regimes, Biotic Responses, and Vegetation Patterns Viewed in the Responses, and Vegetation Patterns Viewed in the
Context of Four Space-Time Domains.Context of Four Space-Time Domains.
SuccessionSuccession
Clements’ ViewClements’ View Plant community associations that remain Plant community associations that remain
intactintact Gleason’s ViewGleason’s View
Species are distributed individualistically Species are distributed individualistically according to their tolerancesaccording to their tolerances
Changes in Northern Arizona Vegetation Zones Changes in Northern Arizona Vegetation Zones from Packrat Middens from the Grand Canyonfrom Packrat Middens from the Grand Canyon
Gradient Studies and Elevational Effects During Gradient Studies and Elevational Effects During the Last Glacial Maximumthe Last Glacial Maximum
Vegetation Change over the last 18,000 years in Vegetation Change over the last 18,000 years in the Northern Great Basinthe Northern Great Basin
Changes in Northern and Western Range Limits for Four Important Eastern North American Tree Taxa During the Late Quaternary Based on Pollen Records.
Maps Depicting Changes in Range Limits Expressed in Contoured Values of Percent Dominance in Forests for Oak.
http://www.ngdc.noaa.gov/paleo/pollen/viewer/webviewer.html
Individualistic ResponseIndividualistic Response
Cold HardinessCold Hardiness Response to DisturbancesResponse to Disturbances
Lower Cold Hardiness Thresholds (Killing Temperatures) Lower Cold Hardiness Thresholds (Killing Temperatures) Summarized for 25 Woody Angiosperms from the Eastern Summarized for 25 Woody Angiosperms from the Eastern
Deciduous Forest.Deciduous Forest.
Cold Hardiness Zone Map.Cold Hardiness Zone Map.
Region A less than -40 ºCRegion B may reach -40 ºCRegion C does not reach -40 ºC
DisturbancesDisturbances FireFire
Itasca State Park, Northwestern MinnesotaItasca State Park, Northwestern Minnesota Western Margin of the Hemlock-White Pine-Northern Western Margin of the Hemlock-White Pine-Northern
Hardwood Forest RegionHardwood Forest Region Changing Fire Frequency 33 or 44 years to 80-90 yearsChanging Fire Frequency 33 or 44 years to 80-90 years
ClimateClimate Controls VegetationControls Vegetation Feedbacks to FireFeedbacks to Fire
Insect OutbreaksInsect Outbreaks
Changes in Fire Frequency in Northwestern Minnesota Changes in Fire Frequency in Northwestern Minnesota reflected in a Shift from a 44-year Cycle to an 88-year reflected in a Shift from a 44-year Cycle to an 88-year
Cycle (from Clark 1988)Cycle (from Clark 1988)
Distinct Vegetation Types Due to Critical Climatic Distinct Vegetation Types Due to Critical Climatic ThresholdsThresholds
Vegetation Dependence on Climatic Factors Controlling Vegetation Dependence on Climatic Factors Controlling Final Stable Vegetation StateFinal Stable Vegetation State
Tree Species Decline and Recovery Due to Tree Species Decline and Recovery Due to Pathogens from Pout Pond, New HampshirePathogens from Pout Pond, New Hampshire
Pollen Accumulation Rates for Black Ash and Pollen Accumulation Rates for Black Ash and Ironwood/Hornbeam for the Late-Glacial IntervalIronwood/Hornbeam for the Late-Glacial Interval
Forest ModelsForest Models
FORETFORETJABOWAJABOWA
Human EvolutionHuman Evolution
North American Land Mammal Ages
Rancholabrean Bison, Mammuthus, Equus, Modern taxa 0 - 0.5 Ma
IrvingtonianMammuthus, Equus, Euceratherium, Smilodon, Mocrotus
0.5 - 1.8 Ma
BlancanEquus, Nannippus phelgon, Stegomastodon, Borophagus diversidens, Trigonictis, Nekrolagus, Procastoroides, Sigmodon.
1.8 - 4.5 Ma
HemphillianMachairodus, Agriotherium, Plesiogulo, Osteoborus, Osbornoceros, Prosthennops, Pliohipppus, Astrohippus
4.5 - 8.2 Ma
Megafaunal ExtinctionMegafaunal Extinction
Pleistocene ExtinctionsPleistocene Extinctions
Radiocarbon-Dated MegafaunaRadiocarbon-Dated Megafauna
Timing of Megafaunal Extinctions at Different Timing of Megafaunal Extinctions at Different Locations (from Sturart et al., 2004 )Locations (from Sturart et al., 2004 )
Worldwide Megafaunal ExtinctionsWorldwide Megafaunal Extinctions
Land Bridges During Land Bridges During the Last Glacial the Last Glacial MaximumMaximum
Human Expansion Human Expansion into the Americasinto the Americas
Marine OverkillMarine Overkill