Koontz, J., D.G. Huggins, C.C. Freeman, D.S. Baker - Central Plains ...

Evidence that waterfowl and/or amphibians are present or would be present during the migratory
season, suggests the wetland is capable of providing wildlife habitat, including food and nesting
cover.
Endangered or Threatened Species warrant further protection of the area under federal laws and
would thus generally discourage disturbance.
Interspersion (Mack 2001) refers to natural non-uniformity in wetland habitat design. Some
native wetland species require multiple habitat-types. If these habitat-types are not in close
proximity to one another, or interspersed throughout the wetland area, then it may be difficult for
such species to survive. The assumption is that between two wetlands of the same size and with
the same proportions of open-water to vegetated habitat, the one exhibiting the greatest
interspersion of habitats likely will support greater native wetland biodiversity and will be more
similar to a „reference‟ state.
Connectivity refers to a wetland‟s functional and structural connection to other landscape and
hydrologic features. Features that disrupt connectivity, such as river or stream impoundments,
levees, berms, or other water structures, can be easily identified on a local level and indicate
disruptions to historical hydrologic regimes. It is more difficult to assess broad-scale and
cumulative hydrological impacts to floodplain wetlands since at some scale nearly all floodplains
and riverine systems have become hydrologically altered to some degree. This assumes most
floodplain wetlands were originally connected to the river or that water was able to cycle
between these systems intermittently.
Disturbance
Metrics that indicate human disturbances known to degrade wetland health are listed in this
section of the Disturbance Assessment. For each disturbance a point is subtracted. If the
disturbance is unusually severe or at a high rate of occurrence, then more than one point can be
subtracted.
Sedimentation is a natural process for wetlands in the Missouri River floodplain, however
modern land use changes that affect the spatial and temporal extent of permanent ground cover
can accelerate soil loss and increased sedimentation (observed as plumes or fresh deposits within
wetlands) that dramatically affect the structure and function of wetlands. Scoring the extent of
wetland sedimentation is not dependant on the identification of anthropogenic or natural causes.
Upland soil disturbance or tillage in the immediate area drained by the wetland is scored
separately as a local disturbance that demonstrates the potential for excessive sedimentation,
although it may not be observable at the time of evaluation.
The presence of cattle is not considered a natural occurrence, even in circumstances where the
cattle graze the wetland periodically throughout the year.
Excessive algae usually suggest an imbalance within an aquatic ecosystem (i.e. excessive
nutrients or eutrophication). Regardless of whether the cause is fertilizer run-off, sediment
resuspension, or cattle, the presence of excessive algae can impede the growth of
aquatic/emergent plant life and threatens the survival of some aquatic organisms.
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