Water Ecology Test

What are the main parts of the “ice year”?

Freeze up, Main Winter, and Ice Break-Up

What are the main types of river ice?

Frazil ice and Anchor Ice (Dynamic) & Border Ice and Sorface Ice (Static)

What are the main physical effects of river ice on habitat conditions?

Velocity decrease makes middle faster (Ice friction), habitat alteration Light reduction, Dissolved oxygen dynamics, sediment transport and scour.

What ecological effects does river ice have?

Invertebrates: some bugs have cold hardiness and purposely freeze to avoid predators, species specific responses, increased drift during dynamic ice events

Fish: (EGG INCUBATION ice scour and freezing can damage eggs, anchor ice over eggs can reduce oxygen for eggs and they have to get it from ground instead)  & (DISTRIBUTION small fish hide in substrates, large fish go to deeper pools, some use ice for cover) (VEGETATION ice scouring and sediment movement change aquatic and riparian plant communities)

What is the concept of stream orders and zonation?

Stream Orders: A hierarchical classification of streams (1st order = headwater streams, Higher orders = formed when lowers order streams merge) as order increases, channel size, discharge, and sediment load increase and gradient generally decreases.

Zonation: Different zones in a drainage basin (Erosion, Transportation, Deposition)

Name some important Canadian rivers, and where does their water flow?

1. Mackenzie River - Arctic Ocean 

2. St. Lawrence River - Atlantic Ocean

3. Fraser River - Pacific Ocean 

What is the water cycle, and what parts does it have?

the continuous movement of water between the atmosphere, land, and oceans.

1. Evaporation and Transpiration - water from land water into atmosphere

2. Condensation - water vapor forms clouds

3. Precipitation - rain or snow returns to surface

4. Infiltration and Percolation - water into the ground

5. Runoff - water flows into rivers and lakes, completing the cycle 

What is a river, catchment vs. watershed, and basin?

River - naturally flowing body of water with a current from source to mouth through a gradient

Catchment: The land area where all precipitation drains to a common outlet.

Watershed: Often used interchangeably with catchment; the boundary dividing different catchments.

Basin: A larger-scale area encompassing one or more watersheds that drain into a common outlet (e.g., Hudson Bay Basin). Open area where water collects 

What are the 3 dimensions of a river channel?

Lateral – River’s connection with its floodplain and banks

Longitudinal – Flow direction from headwaters to mouth.

Vertical (hyporheic) – Interaction between surface water and groundwater.

Understand the concept of habitat and different scales of habitat

Habitat - The place where a species lives, defined by physical and biological characteristics

Macrohabitat – Large-scale, e.g., entire catchment

Mesohabitat – Visually distinct features like pools, riffles, runs; link species to habitat type.

Microhabitat – Small-scale site measurements (e.g., juvenile fish habitat preferences).

What is a hydrograph and what factors affect it?

Hydrograph - A graph showing river discharge (flow) over time (instantaneous, annual, or multi-year).

Factors 

• Local climate and season (snowmelt, rainfall).

• Catchment topography and geology.

• Land use (urbanization, deforestation).

• Lakes or wetlands (flow storage or delay).

• Human impacts (water withdrawal, dams, regulation).

What is hydropeaking?

Hydropeaking refers to rapid, artificial fluctuations in river discharge caused by hydropower generation, where turbines are turned on/off to meet electricity demand. changing it can mess with the species used to a specific discharge for that time of year

What is the concept of environmental flows?

Environmental flows - “How much water does a river need” describe the quantity, timing, and quality of water flows required to sustain ecosystems and human needs that depend on them. (Summer is the zone of highest risk)