Chapter9

What are the origins of streams and rivers?

Streams and rivers originate from glaciers, wetlands, lakes, and springs, receiving water from their drainage basins.

What is a watershed?

A watershed, also known as a drainage basin, is an area that drains into a river or a body of water.

Name four major river basins in Minnesota.

Rainy River Basin, Red River Basin, Lake Superior Basin, and Mississippi River Basin.

What defines a first order stream?

A first order stream is the smallest and youngest type of stream with no tributaries.

What are the physical characteristics of streams?

The physical characteristics include shape, length, gradient, slope, bed composition, turbidity, temperature, and water velocity.

How do flow rates change in streams?

Flow rates differ at various points along a stream and change seasonally and annually.

What factors influence the chemical characteristics of water in streams?

Factors include hardness of water, pH, nitrogen levels, and varying oxygen levels.

What is the primary productivity in stream ecosystems?

Primary productivity refers to the production of stream vegetation and the washing up of organic matter that provides food and habitat.

What is the importance of the detritus food web?

The detritus food web is more important than the grazing food web as it is based on the breakdown of organic matter.

What are the four groups of organisms based on their relationship to moving water?

Fixed organisms, drifting organisms, floating organisms, and active swimmers.

What is the River Continuum Concept?

The River Continuum Concept describes the energy flow and nutrient uptake along the stream, dividing a river into three sections.

Give an example of an organism that has adaptations to flowing water.

Examples include black fly larvae, caddisfly larvae, crayfish, and trout.

What is coarse organic matter in streams?

Coarse organic matter (CPOM) includes large organic materials like leaves and branches.

What is the difference between complete and incomplete metamorphosis in macroinvertebrates?

Complete metamorphosis involves distinct stages: egg, larvae, pupae, and adult, while incomplete metamorphosis has immature stages resembling miniature adults.

What are the two categories of pollutants affecting the Minnesota River?

Point pollutants, such as industrial waste, and non-point pollutants, like nitrogen and surface runoff.

What ecological impact does St. Anthony Falls have on the Mississippi River?

St. Anthony Falls serves as a barrier for many aquatic species, affecting their migration.

What is the significance of the Mississippi River in terms of biodiversity?

The Mississippi River is home to 119 fish species, including four that are threatened or endangered.

Name one way humans have negatively impacted streams.

The construction of lock and dams has been a major threat to stream ecosystems.