Dynamics of Pioneer Forests Along the Wisconsin River: Landscape, Local and Temporal FactorsEPA Grant Number: U915421
Title: Dynamics of Pioneer Forests Along the Wisconsin River: Landscape, Local and Temporal Factors
Investigators: Dixon, Mark A.
Institution: University of Wisconsin - Madison
EPA Project Officer: Lee, Sonja
Project Period: June 1, 1998 through May 1, 2001
Project Amount: $74,866
RFA: STAR Graduate Fellowships (1998) RFA Text | Recipients Lists
Research Category: Academic Fellowships , Ecological Indicators/Assessment/Restoration , Fellowship - Ecology and Ecosystems
The objective of this research is to understand how the establishment of riparian tree species is influenced by spatial variation in physical factors at local and landscape scales and by temporal variation in the magnitude and timing of river flow.
This research addresses three major questions:
1. What are the effects of physical factors at local (sandbar) and landscape (river reach) scales on the distribution of seedlings of pioneer riparian tree species?
2. What are the effects of temporal variation in flow magnitude and seasonal timing on the establishment and composition of tree species?
3. What are the effects of historical flow variation on decadal scale changes in channel and forest area in the Wisconsin River?
Question 1 is being addressed through field sampling of seedlings and topography on newly colonized sandbars within a 16-km reach of the Wisconsin River and by analysis of the effects of physical factors at different scales on seedling occurrence and abundance. Question 2 is being addressed by annual (1997-2000) surveys of seedling species composition and elevation relative to river stage and by examining differences in species composition among years with differing magnitudes and timing of spring and summer flows. The interactions between flow and seedling establishment will be modeled and used to predict the suitability of conditions in different years to recruitment and survival of different seedling species. Model predictions will be partially tested by comparing known establishment years of seedlings, saplings, and trees with years of seedling establishment predicted by the model, based on historic flow records. Question 3 will be addressed through a geographic information systems (GIS) analysis of changes in river channel and forest cover, as derived from historic aerial photographs, in combination with statistical analysis of historic flow patterns in the intervals between the aerial photograph dates.