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Human Impact
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Road construction resulted in filling and paving of meadow edges in
a few locations.
© NPS photo Athena Demetry.
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The Sequoia Ecosystem
Development had extensive impacts on the overall giant
sequoia ecosystem - soil, water, vegetation, animals,
and processes that shaped the forest.
One such process is fire. It is a natural process that
has shaped giant sequoia forests for millennia. Due to
the presence of buildings, the park prevented fire from
burning in and around the developed area. Yet without
fire, giant sequoia seedlings fail to germinate. With no
young sequoias to replace them, the towering sequoias in
the Village area would be the last to stand there. Learn
more about the Sequoia and Kings Canyon National Parks
fire management program at the
SEKI Fire Cache.
Modification of landforms
caused water runoff from
rainstorms and snowmelt to concentrate and form gullies,
increasing soil erosion. Landforms had been modified in
several ways: (1) creating level pads for buildings and
parking lots, (2) cutting into slopes and side-casting
this material to construct road benches, and (3) filling
over wetland and stream areas.
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Workers labor to remove the Giant Forest sewer
facilities at Deer Creek. © NPS Photo by Athena
Demetry. |
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Wetland and stream habitats may have been affected by
leaking sewage where aging sewer lines ran alongside or
across streams. Runoff from parking lots and the gas
station likely contained petroleum residues, which may
have altered wetland and stream habitats. Soils had
become more compact,
eroded,
depleted of organic matter,
and altered from natural crumb and granular structures.
The natural litter and duff layer was absent from the
forest floor. These impacts likely reduced the ability
of surface soils to hold water and nutrients and
maintain the aeration necessary for root health.
Organically rich topsoil is a precious resource; its
loss or degradation can have serious long-term
consequences for ecosystem health.
The structure of the vegetation had been altered. The
mature forest overstory was less dense than that of the
surrounding
forest because trees that threatened human
safety and property were removed. Trees were also
cleared for buildings and parking lots, creating
distinct openings in the forest overstory. The forest
floor was barren because soil compaction and foot
trampling reduced germination and growth of the forest
understory (grasses, wildflowers, shrubs, and tree
seedlings). The diminished forest understory produced
fewer inputs of seed to the soil. With less seed stored
in this "soil seed bank," the regenerative potential of
the forest was reduced. In the extreme case, widespread
covering of soil surfaces by asphalt completely
prevented seed inputs.
Footnote: However, the lower
density forest seen in the Giant Forest Village today may be
similar to the forests that existed prior to the arrival of
Euro-Americans, who suppressed fires that would naturally
thin out dense stands of young trees. Early visitors to the
sequoia groves described an open, "park-like" forest
structure. Among other changes, today’s forests that have not
sustained fire for nearly a century are more closed, with
higher densities of white fir trees that are able to
reproduce in shade.
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