aquatic ecosystems

aquatic ecosystems are classified

based on features of the physical environment

what is a major feature influencing aquatic organisms

salinity

marine (saltwater) ecosystems

open-water

coastal

freshwater ecosystems 

iotic

lentic

what does iotic mean

flowing water (rivers and streams)

what does lentic mean

non flowing water (ponds, lakes, wetlands)

all aquatic ecosystems are linked directly or indirectly as parts of the

hydrological cycle

lakes and ponds are

inland depression

what is a pond

• sunlight reaches the bottom in most areas

• rooted plants to grow across much of the area

ponds are typically [what] than lakes

shallower and smaller

what is a lake

• may have areas where sunlight cannot reach the bottom

• usually have distinct zones with thermal stratification

lakes are typically [what] than ponds

larger and deeper

characteristics of florida lakes

• shallow

• mix frequently (preventing stratification)

• submersed plants along the whole basin

• do not have distinct lake zones

• most were formed as sinkhole lakes from the erosion of limestone

there are over [#] lakes in florida

7,700

why are florida lakes important

support biodiversity and provide natural resources

what is a kettle lake

form when large chunks of glacial ice break off, become buried in sediment, and later melt

what is a pothole lake

formed where glaciers carved out a depression that later filled

types of lakes formed by glacial erosion and depression

kettle and pothole lakes

what is an oxbow lake

u-shaped body of water formed when a river meander becomes cut off from the main channel through erosion and deposition

types of lakes formed by rivers damming themselves with sediment

oxbow lakes

what is a tectonic lake

form by faulting or subsidence of the earth’s crust

what is a crater lake

form in the caldera of extinct volanoes

what lakes originate from tectonic or volcanic activity

tectonic and crater lakes

what are solution/sinkhole/karst lakes

form through the chemical dissolution of soluble bedrock

what lakes originate through geological dissolution

solution/sinkhole/karst lakes

what lakes originate through nongeological activity

lakes are formed by beaver dams, human-created damns, quarries, and surface mines

what is a littoral zone

shallow, nearshore area

what is a limnetic zone

open water

what is a profundal zone

deeper water below the reach of sunlight

what is a benthic zone

bottom of the lake

life is most abundant in the [blank] zone

littoral zone

why does the littoral zone have the richest aquatic life

• sediments accumulate and keep water depth low

• sunlight reaches the bottom

• plants provide food and habitat

phytoplankton act as the main primary producers in the [blank] zone

limnetic

what is considered a key link in energy flow

zooplankton feeding on phyotplankton

spring and fall turnover bring

bottom nutrients to the surface

spring and fall turnover causes a 

phytoplankton bloom followed be a population decline once nutrients are depleted

fish make up most of the nekton in the [blank] zone

limnetic zone

fish distribute themselves based on

food, oxygen, and temperature

whe [blank] zone contains organic debris that sinks from above or washes in from the shore

benthic zone

the benthic zone is typically dominated by

anaerobic bacteria and periphyton

what does oligotrophic mean

low in nutrients, clear water, supports fewer plants and algae

what does mesotrophic mean

moderate nutrient levels with a balanced amount of plant and algal growth; intermediate clarity and oxygen

what does eutrophic mean

high in nutrients, leading to dense plant and algal growth; often murky, with low oxygen in deeper waters due to decomposition

what does dystrophic mean

brown, tea-colored lakes rich in organic acids; low nutrients, low pH, and limited productivity

as streams move downhill,

their path and flow are shaped by the landscape

as streams flow father from their sources,

they grow larger and their physical features begin to shift

what are headwaters

small, fast, and straight; often with rapids and waterfalls

what is midstream

as the slope decreases, the stream slows down, begins to meander, and deposits sediment

what is mouth

where the river empties into a lake or ocean. velocity drops sharply, sediment settles

a stream’s order increases only when

two streams of the same order meet

what is a first-order-stream

small headwater stream with no tributaries

what is a second-order stream

forms when two first-order streams join

what is a third-order stream

forms when two second-order streams join

orders 1-3

headwater streams

orders 4-6

medium-sized streams

7-12

rivers

what are some fast moving stream adaptations

• streamlined bodies to reduce drag

• flattened bodies and broad limbs that help insect larvae cling to rocks

• protective cases that anchor larvae to stones

• sticky undersides in snails and planaria for gripping surfaces

• filamentous algae cling tightly substrate

what are some slow moving stream adaptations

• tolerate lower oxygen and use gills or siphons

• organisms don’t need strong anchoring structures

• feed on fine organic particles (collectors, filter feeders)

• life in soft bottoms (burrowers, detritivores)

• support more plants and algae

what are different feeding roles

shredders, collectors, grazers, gougers, predators

what do shredders do

break down leaves and coarse organic matter while feeding on the microbes growing on them

what do collectors do

filter or gather fine particles created by shredders

what do grazers do

scrape algae from rocks and other surfaces

what do gougers do

burrow into waterlogged wood for food and shelter

what do predators do

insect larvae and fish that feed on grazers and detrital feeders

what is the river continuum concept

abundance of each feeding group changes predictably from headwaters, to midstream, to downstream