APOSTLE ISLAND NATIONAL LAKESHORE VEGETATION COVERAGE
-- A GIS FRAMEWORK
Hong S. He and Stephen J. Ventura
Land Information and Computer Graphics Facility
University of Wisconsin-Madison 53706
ABSTRACT
A complete GIS-based vegetation coverage was created for the Apostle Islands National
Lakeshore, Wisconsin. This coverage integrated previous studies on vegetation with new data from
a recent floral inventory, air photo interpretation, and other GIS layers such as soils, hydrography,
and digital elevation models. Species composition, as defined by overstory tree species, was used
as the spatial unit for vegetation classification.
OVERVIEW
During the last two decades, numerous studies
have used GIS to map vegetation (Kuchler and
Zonneveld 1988; Krummel 1987). Vegetation in
the form of land cover or land type (Gustafson
and Parker, 1992) has become one of the most
essential data layer in GIS (Ripple, 1994). A
digital vegetation layer in GIS is more efficient
both for comparison with other environmental
factors or for quantitative inventory of amount
and size distribution of vegetation patches, and
for single to multi-purpose vegetation mapping
(DeMers, 1991). Recent studies have used using
GIS functionality to simulate vegetation
distributions (Davis and Geotz, 1990) as well as
vegetation based land types, landscape patterns
(Boumans and Sklar, 1990; Turner ef al., 1989;
Mladenoff ef al., 1993). Many studies in this
field are using GIS to analyze vegetation
changes (Iverson and Risser, 1987), species
distribution (Miller et a/. 1988), or landscape
pattern (Pastor and Broschart, 1990; Mladenoff
and Host, 1994). The objective of this paper is to
present our efforts to create a GIS-based
vegetation coverage for the Apostle Island
National Lakeshore ( Figure 1) that can be used
for multiple management and research
applications.
The Apostle Islands National Lakeshore consists
of 21 islands lying off the northern tip of
Wisconsin in Lake Superior and an eighteen
mile long mainland unit in one mile width. Due
to their historical and ecological importance,
these 22 units, comprising about 42,500 acres,
59
were designated by the Congress in the 1970s as
a National Lakeshore. During the last two
decades, a variety of environmental and resource
inventories have been conducted on many of the
islands. The inventories covered flora, fauna,
geology and soils (Anderson et a/., 1979, 1980,
1982, 1983; Brander et al., 1978; Judziewicz
and Koch, 1992; Judziewicz, 1993; Kotar et al.,
1992). Plant research has produced some of the
most complete and detailed data sets. By 1993,
803 species and hybrids representing one-third
of Wisconsin's flora had been recorded, and a
flora database recording plant species and
location labels had been established (Judziewicz
and Koch, 1992). To meet future management
goals, a complete vegetation coverage was
among the top priorities of the National Park
Service.
Figure 1 Geographical Location of AINL
We incorporated a recent plant inventory and
current mapping tasks into a GIS framework to
establish a vegetation coverage (Ventura and