Freshwater Ecology and Stream Continuum

Flashcards covering terrestrial zonation, stream orders, lotic vs. lentic systems, and the river continuum concept based on the lecture notes.

Hadley cell

An atmospheric looping pattern where warm air rises at the equator, cools, condenses, and precipitates, driving the global distribution of tropical rainforests and deserts.

Lower Montane zone

The lower elevation mountainous ecological zone.

Subalpine zone

An ecological elevation zone situated above the lower montane zone and below the alpine zone.

Alpine zone

The highest mountain zone characterized by conditions where trees cannot grow.

Lotic system

A freshwater biological zone characterized by flowing water, such as streams and rivers.

Lentic system

A freshwater biological system containing non-flowing or standing water, such as lakes.

First order stream

The smallest stream classification, typically located at higher elevations where gravity initiates water flow.

Headwater stream

A stream categorized within the first through third stream orders, representing the start of a river system.

Riffles

Fast-moving shallow sections of a stream flowing over coarse particles like rocks, providing high oxygen levels.

Pools

Deeper and slower-moving areas of a stream with finer sediments where fish frequently travel and rest.

Benthic organisms

Bottom-dwelling organisms, such as aquatic invertebrates, that live on or in the substrate of a stream bed.

Detritus

Dead organic material in an ecosystem, including leaves, sticks, and dead organisms.

Hyporheic zone

The substrate region located beneath the benthic zone of a stream bed.

River continuum concept

An ecological framework relating biological community changes and biodiversity to the stream order and size.

CPOM (Coarse Particulate Organic Matter)

Organic matter in aquatic systems, such as leaves and branches, that is larger than $1\,mm$ in size.

FPOM (Fine Particulate Organic Matter)

Organic particles in aquatic systems that are smaller than $1\,mm$ in size, created as coarse matter breaks down.

Shredders

Stream organisms, such as stonefly larvae, that feed by tearing up and chewing coarse particulate organic matter.

Collectors

Aquatic organisms that gather fine organic material from the ecosystem or use it to construct structures.

Scrapers

Organisms predominant in mid-order streams that feed by scraping algae and biofilm off rocks and submerged surfaces.

Periphyton

A complex mixture of algae, bacteria, and organic matter growing on submerged surfaces like rocks or logs in a stream.

Macrophytes

Plants that grow submerged in or surrounding aquatic environments.