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Forest Successional Processes in the E. S. George Reserve, Livingston County, Michigan. Ivette Perfecto John Vandermeer. The transformation of the Oak-dominated forests. Oak-domination is an anthropogenic product of Native American agriculture and hunting activities.
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Forest Successional Processes in the E. S. George Reserve, Livingston County, Michigan Ivette Perfecto John Vandermeer
The transformation of the Oak-dominated forests • Oak-domination is an anthropogenic product of Native American agriculture and hunting activities. • Red maple (Acer rubrum) survived in swamps and is now spreading. • American beech (Fagus americana) and sugar maple (Acer saccharum) were eliminated from vast areas.
The transformation of the Oak-dominated forests • Since sugar maple and American beech are not very common in these forests, we expect recruitment limitation to occur. • We also expect a fat-tail distribution of seed dispersal (as suggested by Clark et al., 1998) No. seeds Distance
The transformation of the Oak-dominated forests Oak Red Maple Sugar Maple American Beech
OBJECTIVES • 1) Estimate the possible time-course of replacement of oaks by red maple. • 2) Estimate the possible long term time-course of replacement of red maples by American beech and sugar maple.
SITE AND METHODOLOGY E. S. George Reserve one 16 hectares three 100 X 70 M2 Plus one 100 X 70 M2 plot at the Patterson Lake Facility
DISTRIBUTION OF BEECH 62 surviving offspring: from seedling to 10 cm dbh 2 largest are 70 and 78 years old 60 hectares were surveyed
Data to be Collected • Continue the censuses of small plot (summer 2003-2004) • Locate and tag all seedlings and saplings near remnant reproductive red maples (summer 2003-2004) • Seed traps near the two reproductive red maples (fall 2003) • Sugar maple seedlings will be planted in forested areas (mainly in the Patterson Lake Nature Center, if it remains available) to verify that suitable microhabitats
Analyses • Seed traps we will provide an accurate estimate of the seed shadow of the two remnant sugar maples. • The data will allow us to determine if there is a "fat tailed" distribution. • Spatial simulation model by Higgens et al. (2001)
Analyses • With the 2004 re-census it will be possible to estimate both the mortality rate of all trees and the growth rate of all trees. • Estimates of the time course of the replacement of the oaks and hickories by the red maple. • Here the modeling framework will be a simple stage structured model (Caswell, 2001).
Future Research • Depending on the results, the new proposal to NSF may include aspect of dispersal limitation and neutral competition (Hubble et al, 1999; Vandermeer et al, 2000) as mechanism for the maintenance of diversity. • Comparison between these mechanisms in tropical and temperate forests.