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<p>To satisfy a growing population, much of Earth’s surface has been designed to suit
humanity’s needs. Although these ecosystem designs have improved human welfare, they
have also produced significant negative environmental impacts, which applied ecology
as a field has attempted to address and solve. Many of the failures in applied ecology
to achieve this goal of reducing neg- ative environmental impacts are design failures,
not failures in the science. Here, we review (a) how humans have designed much of
Earth’s surface, (b) the history of design ideas in ecology and the philosophical
and practical critiques of these ideas, (c) design as a conceptual process, (d) how
changing approaches and goals in subfields of applied ecology reflect changes and
failures in design, and (e) why it is important not only for ecologists to en- courage
design fields to incorporate ecology into their practice but also for design to be
more thoroughly incorporated into ours.</p><p>One of the most heavily altered and
designed ecosystems in the world is the mountaintop mines of Central Appalachia. Mountaintop
mining is the most common form of coal mining in the Central Appalachian ecoregion.
Previous estimates suggest that active, reclaimed, or abandoned mountaintop mines
cover ∼7% of Central Appalachia. While this is double the areal extent of development
in the ecoregion (estimated to occupy <3% of the land area), the impacts are far more
extensive than areal estimates alone can convey as the impacts of mines extend 10s
to 100s of meters below the current land surface. Here, we provide the first estimates
for the total volumetric and topographic disturbance associated with mining in an
11 500 km2 region of southern West Virginia. We find that the cutting of ridges and
filling of valleys has lowered the median slope of mined landscapes in the region
by nearly 10 degrees while increasing their average elevation by 3 m as a result of
expansive valley filling. We estimate that in southern West Virginia, more than 6.4km3
of bedrock has been broken apart and deposited into 1544 headwater valley fills. We
used NPDES monitoring datatsets available for 91 of these valley fills to explore
whether fill characteristics could explain variation in the pH or selenium concentrations
reported for streams draining these fills. We found that the volume of overburden
in individual valley fills correlates with stream pH and selenium concentration, and
suggest that a three-dimensional assessment of mountaintop mining impacts is necessary
to predict both the severity and the longevity of the resulting environmental impacts.
</p><p>Chemical weathering of bedrock is the ultimate source of solutes for all ecosystems,
a geologic sink of C, and controls the rate at which mountains dissolve into the sea.
Human activities bring large volumes of bedrock to the surface and enhance global
weathering rates. Here, we show watersheds impacted by mountaintop mining for coal
have among the highest rates of chemical weathering ever reported. Mined watersheds
deliver nearly 9,000 kg ha-1 y-1 of dissolved ions downstream. This translates into
a chemical weathering rate ~ 330 mm ky-1, which is 55-times higher than background
total (chemical and physical) weathering. These exceptionally high dissolution rates
result from the production of sulfuric acid by pyrite oxidation. As this strong acid
rapidly weathers surrounding carbonate materials, it not only releases large amounts
of dissolved solutes, it also liberates 10-50 g of rock-derived C m-2 yr-1. This shifts
mined watersheds from net geologic carbon sinks to net geologic carbon sources, further
adding to the carbon costs from burning coal and deforesting these landscapes.</p><p>The
impact from mining will likely last decades for some aspects of recovery and centuries
to millennia for others. To examine the paired forest, hydrologic, and biogeochemical
changes from mining we used a combination of remote sensing and watershed monitoring.
We show that forest recovery on mines is at least twice as slow as typical forest
recovery from clearcutting, and that mined areas have persistent low canopy height
gaps. These vegetative changes are coupled with decreases in runoff ratios as mines
age and water moves through flatter, vegetated landscapes. However, the vegetation
change is uncoupled from biogeochemical processes, with strong alkaline mine drainage
signals persisting for decades, even as vegetation recovers.</p>
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