Pictures of Terrestrial Integrity:
Combining Maps for Each Goal
The final step in depicting terrestrial ecological
integrity of the basin assessment area was to combine all components under each goal into maps
depicting overall conditions for each of the three
goals. Similarly, Lyons and others (1995) produced composite maps to depict overall integrity
conditions of fish assemblages in their study.
They calculated index values for sites as the
sum of the scores for their integrity components.
Majer and Beeston (1996) followed a similar
method to depict overall biological integrity of
ant assemblages in Australia.
The database created for each component above
displayed conditions for each 4th code HUC in
the basin assessment area. Components denoted
as number of species were then normalized in the
database to values ranging from 0 to 100 percent
by dividing the number of species in each HUC
by the total number of species possible in each
assessment component and multiplying by 100.
Components denoted as percentages were not
changed. In this way, all components were represented in the database as percentage values
within each 4th code HUC.
Then, for each of the integrity goals, all components were averaged by taking the arithmetic
mean of the percentages for each 4th code HUC.
The results, expressed as mean percentages in
each HUC, were mapped for each of the three
goals. These overall maps depict composite
conditions of all components under each goal.
The overall map for goal 1, maintaining species
viability, is shown in figure 62. Hydrologic unit
codes with higher percentage values in this map
represent locations with more threatened, endangered, endemic, rare, or candidate plants or animals, and overlap with the High Cascade Range
habitat corridor. Thus, the map highlights areas
that may warrant particular management attention
for this goal. Many HUCs ranked moderate (>20
percent mean condition) for goal 1. Several
Hydrologic unit codes ranked moderately high
(>40 percent), particularly in the Cascades Range
in central Washington, the Columbia River Gorge
and adjacent Washington-Oregon border, the Cascade Range in central Oregon, the Klamath Basin
in southern Oregon, the southern WashingtonIdaho border, and a portion of the northern Great
Basin in southeastern Oregon. These are areas
that may warrant particular management attention.
The overall map for goal 2, maintaining long-term
evolutionary potential of species, is shown in
figure 63. Hydrologic unit codes with higher percentage values in this map represent locations
with greater occurrence of disjunct species, and
with presence of hot spots and centers of concentration of biodiversity and species rarity or
endemism. As with the first goal, this map highlights areas that may warrant management attention. About half of the HUCs ranked at least
moderate (>20 percent mean condition) for goal
2. Several ranked moderately high (>40 percent),
particularly in the Cascade Range in southern
Washington, Glacier National Park and adjacent
lands in western Montana, the Idaho-Montana
border, the Blue Mountains and Hell’s Canyon
areas of the Washington-Oregon-Idaho conjunction, and parts of the Snake River Plain and
Owyhee Uplands in southern Idaho. There are
likely additional HUCs that rank moderately high
for goal 2 in southern Idaho for plant hot spots
that did not get identified.
The overall map for goal 3, managing for multiple
ecological domains and evolutionary timeframes,
is shown in figure 64. Hydrologic unit codes with
higher percentage values in this map represent
locations with greater occurrences of unique vertebrate assemblages, and locations with large carnivores (that is, the full trophic ladder). About
one-third of the HUCs ranked moderate (>20 percent mean condition) for goal 3, and none ranked
high. This is not surprising, as most of the components for this goal do not overlap, by definition of
unique geographic assemblages of species. Locations with moderately scored HUCs include
northwestern Montana, the Greater Yellowstone
105
Ecosystem in western Wyoming, the Cascades
Range in northcentral Washington, the Columbia
River Gorge, and much of the Klamath Basinnorthern Great Basin-Owyhee Uplands along
southern Oregon and Idaho. Collectively, these
areas cover some of the margins of the basin
assessment area where unique vertebrate assemblages would be expected to be found in such a
“land-locked” geography.
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A cluster classification of HUCs (fig. 65) among
these three images revealed that goals 1 and 2 are
more similar than goal 3, as may be expected.
Maintaining species viability (goal 1) suggests
maintaining long-term evolutionary potential of
species (goal 2). All three goals and their associated HUC maps, however, provide a full, complementary set of conditions that may prove useful
for guiding ecosystem management planning at
the broad scale.
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Figure 62—Composite map for ecological integrity goal 1, maintaining species viability, terrestrial components. Average
percentage of all 4th-code hydrologic units in the basin assessment area among all components mapped for this goal (see
figs. 44-49).
ICBEMP
State boundaries
Basin boundary
4th field hydrologic
units
Species > 60 − 80%
Species > 80 − 100%
Species > 40 − 60%
Species 1 − 20%
Species > 20 − 40%
Species = 0%
Legend