Watersheds and Wetlands Lecture Review

Practice flashcards for NRM 454 covering watersheds, wetlands, hydrologic cycle, water quality, erosion, and sedimentation.

Why is studying watersheds and wetlands important?

They control water quality, stream flows, and habitat. Management helps reduce flooding, pollution, and biodiversity loss

Define a watershed.

A watershed is land that drains water, sediment, and nutrients to a common outlet, defined by topography

Name two types of watershed management strategies.

Preventative (keep good land uses in place) and restorative (fix problems like erosion or wetland loss)

What is one negative impact on stream hydrology from land use?

Urbanization
R
impervious surfaces reduce infiltration and increase flooding

Write the water budget equation.

P = RO + I + Q + ET
ΔS

Name two lifting processes that cause precipitation.

Cold front (high intensity) and orographic lift (air forced over mountains)

What is the difference between infiltration capacity and infiltration rate?

Capacity = maximum possible infiltration; rate = actual infiltration happening

What happens if rainfall is greater than infiltration capacity?

Surface runoff occurs

Define baseflow and when it dominates.

Groundwater feeding streams between storms; dominates in dry periods and in humid, forested regions

How does urbanization affect a hydrograph?

Steeper rising limb, higher peak, shorter lag time = flashy flow

What is the main goal of the Clean Water Act?

To make waters
fishable and swimmable
by controlling pollution

Give one point source and one nonpoint source of pollution.

Point = factory pipe; Nonpoint = farm runoff

Define eutrophication.

Too many nutrients cause algae growth, oxygen loss, and harm to aquatic life

What dissolved oxygen level is stressful for fish?

Below about 5 mg/L can stress fish

Define erosion and sedimentation.

Erosion = soil is detached and moved; Sedimentation = soil is redeposited

What is the difference between natural and accelerated erosion?

Natural = slow geologic rates; Accelerated = faster from human land use

Name one type of water erosion.

Splash (raindrop impact), Sheet (thin layer), Rill (small channels), or Gully (big channels)

Why is sediment in streams a big issue?

It clouds water, carries pollutants, buries habitat, and lowers oxygen

List one construction erosion control strategy.

Keep disturbed areas small, stabilize quickly, slow stormwater, or retain sediment onsite

How do till vs. no-till practices affect erosion?

Tillage = bare soil, more erosion; No-till = keeps residue, less erosion