Quantifying Forest Fragmentation and Total Forest in Hoosier,
Wayne and Chequamegon National Forests from 1992 to 2006
By
Calvin Callahan
An Undergraduate Thesis Proposal
Submitted in Partial Fulfillment for the Requirements of
Bachelor of Arts
In
Geography and Earth Science
Carthage College
Kenosha, WI
2015
1
Quantifying Forest Fragmentation and Total Forest in Hoosier,
Wayne and Chequamegon National Forests from 1992 to 2006
Calvin Callahan
Abstract
The United States Forest Service was established to manage and protect
national forests since 1905. This study is conducted to see how effectively the
national forests are being managed. The three national forests in this study are
Hoosier, Wayne and Chequamegon National Forests. The three national forests were
tested to see if there has been an overall increase forested land, and if the three
national forests have increased forest fragmentation from 1992 to 2006. Land cover
classification data was used from National Land Cover Database. ArcMap is used to
create maps of the land cover classification schemes. The data derived from ArcMap
is then used in a Fragstats, which is a spatial pattern analysis program for
categorical maps. The results from Fragstats are mixed between the three national
forests. Each null hypothesis is rejected or not rejected, depending on which
national forest is being observed. It can be concluded that further investigation
should be done to test the claim that the three national forests are becoming more
fragmented.
2
Table of Contents
Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
List of Figures and Tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Literature Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
United States Forest Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Forest Fragmentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Landscape Ecology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Quantifying Fragmentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Hypothesis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Hoosier National Forest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Wayne National Forest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Chequamegon National Forest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Data Collection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Data Creation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Data Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Land Cover Classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Fragmentation Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Discussion and Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
Future Research . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Works Cited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
3
List of Figures
Figure 1 Map of Hoosier National Forest
14
Figure 2: Map of Wayne National Forest
16
Figure 3: Map of Chequamegon National Forest
18
Figure 4: Map of land use in HNF in 1992, forest vs. non-forest
21
Figure 5: Map of land use in HNF in 2006, forest vs. non-forest
22
Figure 6: Map of land use in WNF in 1992, forest vs. non-forest
23
Figure 7: Map of land use in WNF in 2006, forest vs. non-forest
24
Figure 8: Map of land use in CNNF in 1992, forest vs. non-forest
25
Figure 9: Map of land use in CNNF in 2006, forest vs. non-forest
26
List of Tables
Table 1: Hoosier National Forest: Forest Fragmentation Indices
22
Table 2: Wayne National Forest: Forest Fragmentation Indices
24
Table 3: Chequamegon National Forest: Forest Fragmentation Indices
26
4
Literature Review
Introduction
Fragmentation of forests is a reoccurring issue, which has a negative impact
on forests in multiple ways. Forest fragmentation can be caused by natural and
anthropogenic causes. However, most forest fragmentation is caused through
anthropological ways (Dellasala, 2002). The national forests were established in
1891 to maintain the adequate care, management and protection of the national
forests (Hoosier National Forest, web). This study is intended to help discern
whether there has been an increase or decrease of fragmentation in the Hoosier,
Wayne and Chequamegon National Forests from 1992 to 2006, and if the overall
amount of forested land increased or decreased in each of the National forests from
1992 to 2006.
Southern Indiana is densely populated with a forest landscape that is
continuing to become fragmented. The Hoosier National Forest controls a large
portion of the forested area throughout southern Indiana, and accounts for over
202,000 acres of land. It was not until 1935 the state of Indiana was allowed to
purchase the land the HNF resides on today. The Weeks Act is what allowed the HNF
to become into a national forest (Teena Ligman, 2011). The Civilian Conservation
Corps (CCC) was one of President Franklin Roosevelt’s New Deal programs that
allowed the HNF to become accessible. The CCC was responsible for building many
of the roads, bridges, campgrounds, towers and etc. in the HNF (Hoosier National
Forest, web).
5
The Wayne National Forest is located in the southeastern part of Ohio. The
history of the Wayne National forest is primarily about rehabilitating the forested
land. The Wayne National Forest total coverage is 833,990 acres, but the Federal
Government owns only about 240,000 acres and the rest is privately owned.
Proclamation of the Wayne National Forest was in 1934, but it did not become a
National Forest until 1951. The Civilian Conservation Corps is largely responsible
for the rehabilitation of that Wayne National Forest (History & Culture, Wayne
National forest, web).
The Chequamegon-Nicolet National Forest is located in northern Wisconsin
in the Wisconsin Northwoods. The Chequamegon and Nicolet National Forests used
to be separate National Forests, but in 1993 they were merged into one National
Forest. The Chequamegon-Nicolet National Forest sums up to 1,519,800 acres total.
The Civilian Conservation Corps also played the major role of rehabilitating the
Chequamegon-Nicolet National Forest (History & Culture, Chequamegon-Nicolet
National Forest, web)
United States Forest Service
The United States Forest Service is an agency that focuses on protecting and
managing the national forests in the United States and in Puerto Rico. The agency
was established in 1905. The United States Forest Service is part of the United States
Department of Agriculture, which protects and helps maintain 154 national forests
and 20 grasslands. The agency takes part in extinguishing forest fires, planting trees,
6
improving trails and enhancing the overall condition of the forested lands (About
the agency, U.S. Forest Service, web).
Managing the national forests and grasslands is one of the major important
aspects of the United States Forest Service. The Forest Service has a baseline for
restoration. The Forest Service must take action to restore a national forest when a
national forest or grassland has been degraded, damaged or destroyed. Degraded is
defined by the Forest service as, “Subtle or gradual changes that reduce the
ecological integrity and health.” Damaged is defined by the Forest Service as. “Acute
to obvious changes in the ecosystem.” Destroyed is defined by the Forest Service as,
“Severe degradation or damage removes all macroscopic life and drastically alters
the physical environment” (U.S. Forest Service, Web).
From 1992 to present day, the use of the clear-cutting method of
regeneration harvest has declined significantly in the national forests. This led to a
general decline of timber sale programs. The need for reforestation has lessened
from this, but is still prevalent in the national forests due to natural causes (U.S.
Forest Service, Web). The decline in lumber manufacturing has played a key role in
the reforestation trends in the United States over the past ten years. Reforestation
methods vary across the United States. The Northeast portion of the United States
shows that there is a natural regeneration to forest regeneration, and the south and
west is primarily tree planting. The Midwest and eastern part of the United States is
mostly associated with natural reforestation, but also is associated with tree
planting (2012, Forest Operations Review).
7
Forest Fragmentation
Native forests across the United States have been widely disturbed over the
past few centuries. Forests have been drastically changed in composition, extent,
spatial patterns and structure (Dellasala, 2002). Forest fragmentation can be
defined as isolated patches of forest that have been separated from other forested
areas leaving gaps between sections of the forest. Forests fragmentation can be from
natural causes, farmland, roads, developing areas and etc. Fragmented forests can
be looked at like a bunch of islands in the middle of the sea.
There are many reasons why a forest would become fragmented. Natural
causes can be the reason why a forest would become fragmented, but would be less
likely. Most natural causes to forest fragmentation are contributed by wildfires, or
other natural events. However, much more commonly, forests are fragmented from
activities such as road construction, logging and agriculture, which are causes of
forest fragmentation through anthropagenic origin (Wade, T, 2003).
When a forest becomes fragmented there will be more edges thoughout the
landscape. Edges are boundaries between two types of habitat, such as a river and
its bank, a forest and a field, or a forest and road, and all can be contributed to an
edge effect. Edge effects are more commonly caused by humans, rathan than
occuring naturally. There are some scientists that state such wildlife as deer, quail
and geese tend to be in habitats that are heavily fragmented and do well. Species are
going to react to edge effects in different ways, and some species will decline
heavily, while others will stay stable or even thrive in the anthropenic caused edges
(Collinge, Sharon K, 2009).
8
Habitat fragmentation is considered to be one of the most prominent factors
aiding the loss of species within a forested ecosystem, and in rare cases even
extinction of a species. The severity of fragmentation and the sensitivity of the
ecosystem can greatly influence how much the native plants, animals and natural
ecosystem is compromised or altered. The movement between habitat patches that
is favorable of the native species becomes more dificult, which can lead to smaller
population size, decreased gene flow and possible local extinction. As a forest
becomes increasingly fragmented, more patches become altered by changes within
the same patch itself. The remaining patches become more isolated resulting in
further ecological degredation. There have been documented declines in species due
to fragmentation including numerous taxa, including songbirs, small mammals and
invertibrates (Dellasala, 2002).
Forest fragmentation can be considered “the modern-day plague” (National
Geographic). One of the most obvious negative and dramatic effects from forests
becoming fragmented is the amount of habitat destroyed, which creates tension on
species to be confined to a smaller space and compete more. The increasing
fragmentation of a forest can help aid climate change. Trees play a key role in
absorbing green house gases that greatly contribute to climate change. Forest soils
are typically moist, and without the cover of trees, the soil can quickly dry out, and
can also cause temperature swings. Trees also contribute to the water cycle by
returning water vapor back into the atmosphere by a process called transpiration
(National Geographic).
9
Landscape Ecology
Landscape ecology is the study of the reciprocal effects of spatial patterns
and the ecological processes that occur there. Ecology refers to landscape in two
different ways. The first view of landscape is based upon human scales, such as
forest patches, fields and hedgerows, human settlement and natural ecosystems.
The second view of landscape is an abstraction representing spatial heterogeneity at
any scale (Pickett and Cadenasso, 1995).
Some landscapes can be thought as mosaic, but this concept is driven by
human dominated landscapes. Landscapes are built of discrete, tied together
patches that are differentiated by biotic and abiotic structure or composition. A
patch type that is dominant will act as a matrix, which will make other patch types
appear. For example, experimental forest fragmentation in the Amazon has revealed
that the number of carrion beetles declines with forest fragmentation size, as does
bird diversity (Pickett and Cadenasso, 1995).
Quantifying Fragmentation
Fragstats is a spatial pattern analysis program for categorical maps. The
main use is to be able to gather complex data to understand a certain landscape
structure. The program was published during 1995 in association with the USDA
(United States Department of Agriculture) Forest Service General Technical Report.
To produce results, the user must choose between three different levels of metrics.
The three levels are patch, class and landscape, and within these three levels metrics
10
there are many subcategories that can be selected to produce widely different
functions. (FRAGSTATS: Spatial Pattern Analysis Program for Categorical Maps).
Assessing landscape structure, patch indices serve as a computational basis
for the other landscape metrics, therefore patch may have little interpretive value to
the landscape as a whole. However, patch can play an important role in landscapelevel investigations. The class metric is particularly helpful with landscape
ecological applications and the amount of distribution of a particular patch type
(class). The landscape metric is good for looking at a landscape mosaic as a whole.
The landscape metric focuses on structure, composition and pattern of the entire
landscape (Kevin McGarigal, Barbara Marks, 1994).
Dominick Dellasala conducted a scientific study on forest fragmentation and
used Fragstats to gather data to determine forest landscape patterns. Dellasala
conducted his research on forest fragmentation and assessed forest intactness
through road density and spatial characteristics. Dellasala used the following
Fragstats metrics to quantify forest fragmentation: road density, total core area
index, mean nearest neighbor, class area and percentage of landscape. The research
found that it would be premature to conclude that the forests have recovered and
that further investigation would be needed (Dellasala, 2002).
11
Hypotheses
Based on the literature review, the following hypotheses were formed and
conducted on each of the three National Forests: Hoosier, Wayne and Chequamegon
National Forests. In this study, rather than only having one National Forest, three
National Forests were used to further strengthen the claim of the hypotheses. Also,
only a portion of the forest is analyzed in this study, and does not represent the
entire national forest. The Hoosier, Wayne and Chequamegon National Forests are
all similar in type of forest and are located in the mid-western region of the United
States of America. Also the study area of each National Forest is only a portion of the
National forest, and does not represent the entire National Forest.
Alternative Hypothesis 1: There is an increase in the amount of forest fragmentation
within the National Forests between 1992 and 2006.
Null hypothesis 1: There is not an increase in the amount of forest fragmentation
within the National Forests between 1992 and 2006.
Alternative Hypothesis 2: There is an increase in the total amount of forested land
within the National Forests between 1992 and 2006.
Null hypothesis 2: There is not an increase in the total amount of forested land
within the National Forests between 1992 and 2006.
12
Methodology
Hoosier National Forest
This study examines the Hoosier National Forest study site during the years
1992 and 2006 as well as the land cover and use of the Hoosier National Forest. The
Hoosier National Forest is 202,000 acres and is located in the southern part of
Indiana. The area analyzed of the Hoosier National Forest covers 55,680 acres,
which is highlighted on the map (Figure 2). The landscape of the Hoosier National
Forest is very hilly and mainly deciduous forest. The landscapes throughout Indiana
are attributed to glaciers. Around 16,000 years ago glaciers covered most of Indiana.
The northern and central part of Indiana was covered by glaciers resulting in the flat
plains, lakes and rivers throughout northern and central Indiana. The southern part
of Indiana is very hilly and covered with forests. Southern Indiana became this type
of landscape through the glaciers melting resulting in floods that carved the many
rivers and hills in southern Indiana.
Explorers, settlers and various individuals were making their way into
Indiana in the late 1600’s. There were Native Americans that inhabited the land
before the European settlers moved in. However, in 1816 Indiana became a state
and from that time settlement began to increase dramatically. When the settlers
first acquired Indiana land, one of the first things they had to do was to clear the
land of trees. In the late 1800’s, the lumber industry was flourishing and Indiana
was one of the largest suppliers of timber. This time period had a large effect of the
composition of the forest today. By 1930 the population of the forest area had
declined dramatically and the forest service bought the land in 1935. Today the
13
Hoosier National Forest is under the Forest Service protection. There are many
recreational activities in the HNF such as hiking, camping, climbing, fishing, hunting,
water activities and many more. The HNF is being mined heavily for limestone and
gypsum on private land, as well as timber harvests and prescribed burns.
Figure 1. Map of Hoosier National Forest (U.S. Forest Service, web).
14
Wayne National Forest
This study examines the Wayne National Forest during the years 1992 and
2006 as well as the land cover and use of the Wayne National Forest. The area
analyzed of the Wayne National Forest covers 78,605 acres, which is highlighted on
the map (Figure 3). The landscape of the Wayne National Forest is very similar to
the Hoosier National Forest. The Wayne National Forest is a temperate deciduous
forest located in the hills of southeastern Ohio (Wayne National Forest – Home).
Over the past two million years glaciers have been advancing and retreating in Ohio,
shaping the landscape to what it is today. The mass of continental ice has covered up
to two thirds of the state in the northern and northwestern part of Ohio. The glacier
left the northern and western part of Ohio flat while the southeastern part is filled
with valleys and hills (Shaping the Land – Ohio History Central).
The Northwest Ordinance 1787 is what opened the door for settlers to move
into the land north and west of the Ohio River. Ohio became a state in 1803, and the
population of Ohio increased dramatically. The earliest and heaviest settlements
were in the southeastern part of Ohio, which would be near or around the Wayne
National Forest. The first thing settlers would do was cut down the trees on their
property. In the early 1800’s the timber industry was already cutting lumber and
exporting it from Ohio. In 1849, Ohio ranked fourth among the other states in
producing lumber, and by 1920 nearly all the trees were cut down for lumber. The
Wayne National Forest was established and put under protection in 1934 by the
forest service. Since then, The Wayne National Forest has been in the process of
reforesting the land (History and Culture, Wayne National Forest).
15
Figure 2. Map of Wayne National Forest (U.S. Forest Service, web).
16
Chequamegon-Nicolet National Forest
This study examines the Chequamegon-Nicolet National Forest during the
years 1992 and 2006 as well as the land cover and use of the Chequamegon-Nicolet
National Forest. The area analyzed of the Chequamegon-Nicolet National Forest
covers 68,442 acres, which is highlighted on the map (Figure 4). The ChequamegonNicolet National Forest is also a temperate deciduous forest. The National Forest is
located in the northern part of Wisconsin in the North Woods. Continental glaciers
covered the northern and eastern part of Wisconsin 26,000 years ago. The
Chequamegon-Nicolet National Forest would have been underneath glacier at that
time. The landscape is flat and filled with ponds (Ice Age Geology).
Wisconsin became a state in 1848, and that is when large scale lumbering
started to occur within the Chequamegon-Nicolet National Forest. In 1933, both
lands were acquired for the Chequamegon and Nicolet National Forests. The
restoration of the forest took place during the 1930’s to 1949 by the CCC. It wasn’t
until 1993; they Chequamegon and Nicolet National Forests were merged into the
Chequamegon-Nicolet National Forest (Onel, History of the Chequamegon-Nicolet
National Forest).
17
Figure 3. Map of Chequamegon-Nicolet National Park (U.S Forest service, web).
18
Data Collection
The primary datasets were downloaded from the National Land Cover
Database (NLCD) for both years 1992 and 2006. The NLCD is a land cover
classification scheme that stretches across the lower 48 contiguous United States.
The 1992 NLCD is based primarily on the classification of Landsat Thematic Mapper
™. The 2006 NLCD is based primarily on a decision-tree classification of circa 2006
Landsat satellite data. The 1992 dataset has a total of 21 different classification
schemes and the 2006 dataset has a total of 16 different classifications. The
classification schemes used for 1992 and 2006 were the deciduous forest, evergreen
forest, mixed forest, woody wetlands and emergent herbaceous wetlands. The
primary use of this data was to obtain a landscape identification layer for both years
1992 and 2006.
Data Creation
All maps were created in the program ArcMap. The basemap was obtained
through ArcGIS basemap layer within ArcMap. The editor tool was used to create a
boundary of the three National Forests, using the basemap as a trace. To create the
boundary of the National Forests a shapefile was created and the polygon was
created with the editor tool and stored inside the new shapefile. The new boundary
layer of the National Forests was used to create a mask. The NLCD data was used to
create a mask for both years 1992 and 2006, for all three National Forests. To create
the masks the spatial analyst tool “extract by mask” was used. The masks from 1992
and 2006 were then used to reclassify the values for all three National Forests. After
19
the reclassify tool was ran, the values were changed to forest and non-forested
landscapes. The forested landscapes were set to a value of 1, and the non-forested
landscapes were set to the value 0 for each National Forest. The values needed to be
reclassified so the format could be changed to ASCII, and then be used in Fragstats.
Data Analysis
The data was created within the program ArcMap. Analysis of the data was
performed with the program Fragstats. Fragstats is designed to compute a wide
variety of landscape metrics for categorical map patterns. There are many different
metrics that can be used for analysis within Fragstats. Fragstats has three main
categories of metrics and they are patch, class and landscape level metrics, and
there are many metrics to compute within each category. The metric used in this
study was the class level metrics, total area (TA, which is the total amount of forest
and non forest by hectare); percentage of landscape (%LAND, which shows the
percentage amount of forest and non-forest); largest patch index (LPI, shows the
percentage of the landscape comprised by the largest patch); and mean nearest
neighbor (MNN, which is the average distance in meters between one patch of forest
to another patch). The forest landscapes were set to ID = 1 and the non-forest
landscapes were set to ID = 0.
20
Results
Land Cover Classification
Two maps were created with ArcMap of the Hoosier National Forest showing
forest vs. non-forest land cover classification, one map for 1992 and another for
2006 (Figures 5 and 6). Tables were created using Excel to display the data of the
landscape and class level metrics used (Table 1). Both maps and the table are shown
below.
Figure 4: Map of land use in HNF in 1992, forest vs. non-forest.
21
Figure 5: Map of land use in HNF in 2006, forest vs. non-forest
Table 1: Hoosier National Forest: Forest Fragmentation Indices.
Hoosier National Forest
Classes
Metrics
1992
2006
Change
% Change
TA
11063.8
9886.9
-1176.9
-10.7 %
0 = Non Forest
%LAND
LPI
19.9
4.9
17.8
5.1
-2.2
0.2
-10.7 %
4.1 %
MNN
100.3
146.6
46.3
46.2 %
TA
44616.2
45793.1
1176.9
2.6 %
1 = Forest
%LAND
80.1
82.2
2.1
2.6 %
LPI
75.9
78.2
2.3
3.0 %
22
MNN
80.5
95.1
14.6
18.1 %
Two maps were created with ArcMap of the Wayne National Forest showing
forest and non-forest, land cover classification, one map for 1992 and another for
2006 (Figures 7 and 8). Tables were created using Excel to display the data of the
landscape and class level metrics used (Table 2). Both maps and the table are shown
below.
Figure 6: Map of land use in WNF in 1992, forest vs. non-forest.
23
Figure 7: Map of lad use in WNF in 2006, forest vs. non-forest.
Table 2: Wayne National Forest: Forest Fragmentation Indices
Wayne National Forest
Classes
Metrics
1992
2006
Change
% Change
TA
13617.7
13693.4
75.7
0.6 %
0 = Non Forest
%LAND
LPI
17.3
1.1
17.4
12.3
0.1
11.2
0.6 %
1018.2 %
MNN
91.4
98.2
6.8
7.4 %
TA
64987.9
64912.2
-75.7
-0.1 %
1 = Forest
%LAND
LPI
82.7
80.6
82.6
42.4
-0.1
-38.2
-0.1 %
-47.4 %
MNN
70.8
72.9
2.1
3.0 %
24
Two maps were created with ArcMap of the Chequamegon National forest showing
forest and non-forest, land cover classification, one map for 1992 and another for
2006 (Figures 9 and 10). Tables were created using Excel to display the data of the
landscape and class level metrics used (Table 3). Both maps and the table are shown
below.
Figure 8: Map of land use in CNNF in 1992, forest vs. non-forest.
25
Figure 9: Map of land use in CNNF in 2006, forest vs. non-forest.
Table 3: Chequamegon National Forest: Forest Fragmentation Indices
Chequamegon National Forest
Classes
0 = Non Forest
Metrics
TA
%LAND
LPI
1992 6224.9
9.1
1.6
2006 7088.8
10.3
3.4
Change 874.9
1.2
1.8
% Change 13.8 %
13.2 %
112.5 %
Fragmentation Results
MNN
104.4
133.8
29.4
28.2 %
TA
62217
61342.5
-874.5
-1.4 %
1 = Forest
%LAND
LPI
90.9
90.7
89.6
39
-1.3
-51.7
-1.4 %
-57.0 %
MNN
76.8
84.7
7.9
10.3 %
26
The indices from Fragstats were produced for all three national forests: the
Hoosier National Forest, Wayne National Forest and Chequamegon National Forest.
Each national forest is divided up into two different classes of landscapes, forest and
non-forest. Four indices were produced for each forest and non-forest class in each
of the three national forests.
The Hoosier National Forest data shows that there is a decrease in non-forest
landscape and an increase in forested landscape from 1992 to 2006. The largest
patch index metric shows that for both forest and non-forest landscapes, there has
been an increase in the Hoosier National Forest from 1992 to 2006. There has been
an increase of mean nearest neighbor metric within the Hoosier National Forest for
both forest and non-forest landscapes from 1992 to 2006 (table 1).
The Wayne National Forest data shows that there is an increase in the
amount of non-forested landscape and a decrease in the amount of forested
landscape from 1992 to 2006. The largest patch index metric has increased in the
non-forested landscape and decreased in the forest landscape in the Wayne National
Forest from 1992 to 2006. The mean nearest neighbor metric has increased for both
forest and non-forested landscapes within the Wayne National Forest from 1992 to
2006 (table 2).
The Chequamegon National Forest data shows that there is an increase in the
amount of non-forested landscape and a decrease in the amount of forested
landscape from 1992 to 2006. The Largest patch index metric has increased in the
non-forest landscape and decreased in the forest landscape in the Chequamegon
National Forest from 1992 to 2006. The mean nearest neighbor metric has
27
increased for bot forest and non-forested landscapes within the Chequamegon
National Forest from 1992 to 2006 (table 3).
Discussion
28
The data used in this study was acquired from the National Land Cover
Database. The accuracy of the data from another source could always be a factor to
inaccurate results and conclusions. The overall accuracy assessments of National
Land Cover Database were 79% in 2001 and 78% in 2006 (Wickham, 2013). The
accuracy assessment for the Midwest region is absent for 1992. The legend for 1992
has 21 land cover classifications and is not exactly the same for 2006, which only
has 16 land cover classifications. More detailed land cover classifications would be
beneficial so that the different land cover classifications would not be as vague and
there would be more specific options to choose from for a more accurate land cover
scheme. The data acquired was in three parts as well. The Hoosier National Forest
data for 1992 was downloaded by state level (Indiana data). While the 1992 data for
Wayne and Chequamegon National Forests were used from the same conterminous
United States data (not from state level like the HNF). The 2006 data used was of the
conterminous United States for all three national forests.
The results for the three national forests were not all the same. The Wayne
and Chequamegon National Forests seem to have more congruent results, while the
Hoosier National Forest has very different results. Since the study area is only three
national forests, the results could come back differently if all the national forests
were included in the study.
The null hypothesis #1 cannot be fully rejected for the Hoosier National
Forest. The largest patch index metric for forested land shows that the largest patch
in 1992 is 75.9 m^2 and is 78.2 m^2 in 2006. This shows that there was a slight
increase in forest patch size, which could mean that the forest is not becoming more
29
fragmented. However in 1992 the mean nearest neighbor metric is 76.8 meters and
in 2006 it is 95.1 meters. This shows that there is a larger gap between forest
patches in 2006 than in 1992, which would reject the null hypothesis # 1. The
percentage of landscape metric for the Hoosier National Forest can reject the null
hypothesis # 2. The percentage of forest has gone up in the Hoosier National Forest
by 2.15%.
The null hypothesis # 1 can be rejected for the Wayne National Forest. The
largest patch index metric for forested land shows that the largest patch in 1992 is
80.6 m^2 and is 42.4 m^2 in 2006. This shows that there is a large decrease in
forested patch size, which would mean that the forest is becoming more fragmented,
because there are smaller patches of forested land. The mean nearest neighbor
metric for forested land in 1992 is 70.8 meters and 72.9 meters in 2006. The mean
nearest neighbor metric shows that there is a larger gap between forest patches in
2006 than in 1992, which would reject the null hypothesis # 1. The percentage of
landscape metric for the Wayne National Forest cannot reject the null hypothesis #
2. The percentage of forest has gone down in the Wayne National Forest by 0.1%.
The null hypothesis # 1 can be rejected for the Chequamegon National
Forest. The largest patch index metric for forested land shows that the largest patch
in 1992 is 90.7 m^2and is 39 m^2 in 2006. This shows that there is an even larger
decrease in forested patch size, which would mean that the forest is becoming more
fragmented, because there are smaller patches of forested land. The mean nearest
neighbor metric for forested land in 1992 is 76.8 meters and 84.7 meters in 2006.
The mean nearest neighbor metric shows that there is a larger gap between forest
30
patches in 2006 than in 1992, which would reject the null hypothesis # 1. The
percentage of landscape metric for the Chequamegon National Forest cannot reject
the null hypothesis # 2. The percentage of forest has gone down in the
Chequamegon National Forest by 1.3%.
The NLCD data was used to assess why the results show there is an increase
in fragmentation. The developed land cover classification scheme showed some very
interesting changes. For all three of the study sites, there was a major significant
increase of developed land from 1992 to 2006. The study site in the Hoosier
National Forest showed that there was a 1,216% increase of developed land from
1992 to 2006. The study site in the Wayne National Forest showed that there was a
685% increase in developed land from 1992 to 2006. The study site in the
Chequamegon-Nicolet National Forest showed that there was a 3,583% increase of
developed land from 1992 to 2006. There is an obvious increase in the amount of
roads from 1992 to 2006 when observing the maps of the study sites. (Figures 4, 5,
6, 7, 8 and 9). As mentioned in the literature review, roads are a major cause of
forest fragmentation, and roads would be included in the developed land cover
classification scheme from the NLCD.
Conclusions
The results showed that there is an increase in forested area, but mixed
results in fragmentation for the Hoosier National Forest from 1992 to 2006.
However, the Wayne and Chequamegon National Forest show the opposite, which
means there is a decrease in the forested area, but an increase in fragmentation
31
from 1992 to 2006. It would be premature and inaccurate to conclude that there has
been an increase in the amount of forested land and an increase in fragmentation of
the Hoosier, Wayne and Chequamegon National Forests from 1992 to 2006.
Further investigation into why certain national forests are becoming more or
less fragmented could be conducted utilizing more detailed land cover
classifications provided by the NLCD data. Such knowledge could then help inform
forest management practices and policy making in the future.
Future Research
Further research in forest fragmentation within the national forest system
could greatly help preserve the biodiversity and ecology of the forests. Research of
the entire national forest could be conducted in the future to get a better
understanding of the national forest as whole. Additional national forests would
greatly attribute to the research on forest fragmentation. Repetition of this study
could become part of the national forest system protocol to better manage and
protect the national forests across the United States.
Acknowledgements
32
I would like to give thanks to my academic advisor Dr. Kurt Piepenburg and
my primary thesis advisor Dr. Wenjie Sun and Dr. Joy Mast for their patience,
assistance and guidance of my senior thesis. I would like to give gratitude to the
entire Geography and Earth Science department for their academic knowledge and
assistance. I would also like to thank my peers and fellow Geography and Earth
Science classmates for their input.
Works Cited
33
Forest Operations Review"12-R-5: Recent US Reforestation Trends." 12-R-5: Recent
US Reforestation Trends. 2012. N.p., n.d. Web. 22 Apr. 2015.
http://www.forestoperationsreview.org/safety-alerts/item/229-recent-usreforestation-trends
Wickham, James D., et al. "Accuracy assessment of NLCD 2006 land cover and
impervious surface." Remote Sensing of Environment 130 (2013): 294+. Academic
OneFile. Web. 8 Apr. 2015.
"About the Agency." U.S. Forest Service. About the Agency. N.p., n.d. Web. 06 Apr.
2015.
http://www.fs.fed.us/about-agency
McGarigal, Kevin, and Barbara J. Marks. "Fragstats - Spatial Pattern Analysis
Program for Quantifying Landscape Structure." (1994): n. pag. Web.
Pickett, S.T.A., and M.L. Cadenasso. "Landscape ecology: spatial heterogeneity in
ecological systems." Science 269.5222 (1995): 331+. Academic OneFile. Web. 19 Mar.
2015.
Onel, “History of the Chequamegon-Nicolet National Forests” (n.d.): n. pag. Web.
http://www.fs.usda.gov/Internet/FSE_DOCUMENTS/stelprdb5109506.pdf
"Ice Age Geology." Wisconsin Geological Natural History Survey. N.p., n.d. Web. 19
Mar. 2015.
"Wayne National Forest - Home." Wayne National Forest - Home. N.p., n.d. Web. 19
Mar. 2015.
"Shaping the Land - Ohio History Central." Shaping the Land - Ohio History Central.
N.p., n.d. Web. 19 Mar. 2015
"FRAGSTATS: Spatial Pattern Analysis Program for Categorical Maps." FRAGSTATS:
Spatial Pattern Analysis Program for Categorical Maps. N.p., n.d. Web. 08 Mar. 2015.
"History & Culture." Chequamegon-Nicolet National Forest -. N.p., n.d. Web. 06 Mar.
2015.
"History & Culture." Wayne National Forest -. N.p., n.d. Web. 07 Mar. 2015.
Dellasala, Dominick A., et al. "Forest fragmentation of the conterminous United
States: assessing forest intactness through road density and spatial characteristics.
(Articles)." BioScience 52.5 (2002).
Geise, Sarah. Quantifying Urbanization and Fragmentation of Agricultural and
Forested Lands in Kenosha County 1988-2008. Thesis. Carthage College, 2011.
34
Hoosier National Forest - Home." Hoosier National Forest - Home. N.p., n.d. Web. 15
Apr. 2014.
Teena Ligman. “100 Years of Restoring America’s Forests.” Hoosier National Forest
Highlights. Issue 54. Nov. 30, 2011.
Collinge, Sharon K. Ecology of Fragmented Landscapes. Baltimore: Johns Hopkins UP,
2009. Print
Wade, T. G., K. H. Riitters, J. D. Wickham, and K. B. Jones. Distribution and causes of
global forest fragmentation. Conservation Ecology 7(2): 7. 2003. [online] URL:
http://www.consecol.org/vol7/iss2/art7/
"Deforestation Facts, Deforestation Information, Effects of Deforestation - National
Geographic." National Geographic. N.p., n.d. Web. 21 Apr. 2014.
http://www.nature.org/ourinitiatives/regions/northamerica/unitedstates/indiana
/journeywithnature/how-glaciers-shaped-indiana.xml
35