Ecosystem Restoration Flashcards

Which hydrological indicator is most commonly used to assess progress in wetland restoration projects?

Answer: Groundwater table elevation relative to soil surface

Groundwater table elevation relative to the soil surface directly reflects hydrologic reconnection, the primary goal of most wetland restorations.

In stream restoration, what does the term 'bankfull discharge' represent?

Answer: The flow that fills the channel to the top of the banks and controls channel morphology

Bankfull discharge is the channel-forming flow that fills the stream to its banks and is the dominant control on channel shape and size.

A hydrographer notices that a restored reach has a sinuosity ratio of 1.05. What does this indicate?

Answer: The channel is nearly straight, suggesting possible under-restoration

A sinuosity ratio near 1.0 indicates an almost straight channel; reference reaches for the same valley slope typically have higher sinuosity.

Which method best estimates pre-disturbance channel geometry when designing a stream restoration?

Answer: Aerial photograph analysis of reference reaches with similar drainage area and slope

Reference reach analysis using aerial photos of unimpacted streams with comparable drainage area and slope provides the most reliable pre-disturbance geometry estimate.

What is the primary purpose of installing large woody debris (LWD) in a restoration project?

Answer: To create habitat complexity, pool formation, and sediment storage

LWD creates hydraulic diversity, pool-riffle sequences, and sediment storage that improve aquatic habitat complexity.

During post-restoration monitoring, a rapid increase in bed aggradation upstream of a constructed riffle is observed. What is the most likely cause?

Answer: Excessive sediment supply from an unaddressed upland source

Aggradation upstream of a grade control structure indicates sediment supply exceeds transport capacity, often from unaddressed upland erosion sources.

Which ecological concept guides the selection of target conditions in ecosystem restoration?

Answer: Historical range of variability (HRV) combined with reference ecosystem analysis

Historical range of variability combined with reference ecosystem analysis defines realistic, achievable target conditions that account for natural variation.