Ecosystem Restoration Flashcards

What hydrologic function does a floodplain reconnection project primarily restore?

Answer: Lateral hydrologic connectivity that attenuates floods and recharges groundwater

Floodplain reconnection restores lateral connectivity, allowing flood waters to spread, slow, and infiltrate, reducing downstream peak flows and recharging alluvial aquifers.

A Rosgen Level II survey classifies a reach as a C4 stream type. Which characteristic set defines this classification?

Answer: High sinuosity, low gradient, gravel substrate, well-developed floodplain

Rosgen C streams are high-sinuosity, low-gradient channels with well-developed floodplains; the '4' suffix denotes a gravel-dominated substrate.

Which remote sensing product is most useful for mapping pre-restoration tidal wetland extent to establish baseline conditions?

Answer: Historical aerial photography and topographic charts combined with LiDAR DEMs

Historical aerial photography and topo charts define pre-disturbance conditions, while LiDAR DEMs provide current elevation needed to model tidal inundation.

In a tidal marsh restoration following dike removal, which process most rapidly re-establishes sediment accretion?

Answer: Tidal import of suspended sediment followed by organic matter accumulation

Tidal flows import suspended fine sediment that settles during slack water, and pioneer vegetation roots trap organics, driving rapid elevation gain.

What is 'channel incision' and how does it impair ecosystem function in a restored stream?

Answer: Vertical downcutting that disconnects the stream from its floodplain and lowers the water table

Channel incision lowers the stream bed, disconnecting lateral floodplain access and dropping the riparian water table, degrading both aquatic and terrestrial habitat.

Which biological indicator is commonly used to assess macroinvertebrate community response after stream restoration?

Answer: Ephemeroptera, Plecoptera, and Trichoptera (EPT) taxon richness

EPT richness is a widely used biotic index because these orders are sensitive to habitat and water quality degradation and recover with restoration.

When conducting a sediment budget analysis for a restoration watershed, which term represents the net change in storage within the system?

Answer: Inputs minus outputs plus or minus change in storage

A sediment budget balances inputs, outputs, and storage change: ΔStorage = Inputs − Outputs, identifying sources, sinks, and transport linkages.