Where are coral reefs located?
form in clear, warm coastal waters of tropics and subtropics --> along equator
How are coral reefs formed?
formed by massive colonies of polyps
What do coral reefs require?
dissolved oxygen
light
nutrients
How do coral reefs bleach?
from loss of algae that colors and nourishes them and lack of dissolved oxygen, light and nutrients
coral reefs threats
chemical pollution
global warming
extra UV
excess sediment from rivers (cloudy water)
human contact (collect)
predators (organisms)
natural services of coral reefs
algae do photosynthesis and take in carbon dioxide
protect coastline --> natural barrier for waves, less erosion
build habitats for organisms to hide
plankton
free-floating, drifting organisms
types of plankton
phytoplankton (plant-like)
zooplankton (animal-like)
ultraplankton (tiny)
nekton
fish, turtles, whales (not drifters)
what are the majority of decomposers?
bacteria
benthos
bottom dwellers (clams, oysters, crabs, tube worms)
what varies btwn aquatic system layers?
temp, sunlight, dissolved oxygen, nutrients
euphotic zone
top layer of aquatic system
sunlight can penetrate
lots of light
low nutrient levels (sink)
high photosynthetic activity
high dissolved oxygen
bathyal zone
middle layer of aquatic system
dim/twilight area of open sea
abyssal zone
bottom layer of aquatic system
dark
cold; low temp
no photosynthesis
high pressure
low dissolved oxygen
some nutrients (bc dead things)
organisms blind and produce own light to attract prey
coastal zone
where most action is
high productivity
warm
nutrient-rich: sediments
shallow water
makes up less than 10% of world's ocean area but contain 90% all marine species
what is open ocean made up of?
90 % ocean area and 10% marine species
human impacts on aquatic habitats
dams
cities
farmland
suburban development cities and farmlands add pollutants and excess plant nutrients to streams and rivers that go to ocean
temperate zone locations
above and below tropical zones
tropical zones locations
area near equator; btwn tropic of cancer and tropic of Capricorn
coral reefs and mangroves (special trees)
where do kelp forests grow?
in coastal zone (ex: by channel islands) grow 2 ft per day
Microcystis
not a plant (algae)
AKA giant kelp
provides shelter for many organisms
provides food
higher biodiversity than rainforest
ecological services of kelp forest
provide habitats
absorb carbon dioxide (carbon sink)
increase oxygen levels
structure of kelp
holdfast attaches kelp to rock
reproduces by spores that float and settle in new location
fronds: leaves
air bladder helps fronds stay near surface (sunlight)
what part of kelp do sea urchins eat?
eat base of holdfast and release kelp which washes up on shore (storms also break kelp and push them to shore)
how do sea urchins move?
move in herds and can destroy 30m of forest per month (urchin barrens)
keystone species
presence / absence of species profoundly affects ecosystem
why did hunters kill sea otters?
for their fur for trade
current sea otter threats
oil spills
polluted water --> pollutes food and toxins build up in body
kelp forest benefits
washed up kelp become food for other organisms
beach hoppers --> become food (ex: snow plovers --> endangered)
how are gopher tortoise keystone species?
make burrows for frogs, snakes, owls
how are American alligators keystone species?
gator holes and nests
how are red mangroves keystone species?
prevent coastal erosion, provide hiding places and habitats
how are beavers keystone species?
make areas of still water
how much of earth's surface do saltwater and freshwater aquatic life zones cover?
almost 3/4
functions of aquatic environments
dissolves nutrients --> cycles
dilutes toxins
prevents changes in temp
intertidal zone
area btwn high and low tide
what do organisms in the intertidal zone have to deal with?
changing temp
changing salinity
wave action
desiccation (drying out)
estuaries and coastal wetlands
centers of productivity
where fresh and salt water mixes
plants have to be salt tolerant
tolerant of change in temp/salinity
where are estuaries and coastal wetlands located?
water along coast that is partially surrounded by land
river mouths, inlets, bay, salt marches in temperate zones
mangrove forests in tropical zones
halophytes
salt grass, pickleweed, cordgrass
estuaries and coastal wetlands natural services
filter toxic pollutants
remove excess plant nutrients
trap sediment in runoff
absorb waves --> erosion protection
storing excess water --> prevents flooding
provide food, habitats and nursery sites for many aquatic species
macro
seen w/o microscope
invertebrates
animals w/o backbone
aquatic macroinvertebrates
valuable indicators of health of aquatic environment
benthic
typically found on bottom of stream/lake and do not move over large distances
small, not move quiz/easily (away from pollution)
dif environmental stressors for macroinvertebrate species
pollution, sediment loading, habitat changes
what can indicate condition of body of water?
quantifying diversity and density of dif macroinverts at given site
intolerant vs tolerant macroinverts
intolerant: die when exposed to environmental stressor
tolerant: move in and often inhabit spaces vacated by intolerant organisms when exposed to environmental stressor
result in dif populations of organisms
what type of macroinverts will be in a healthy body of water?
intolerant species
intolerant macroinverts
mayflies (ephemeroptera)
stoneflies (plecoptera)
caddisflies (tricoptera)
tolerant macroinverts
leeches (hirudinea)
tubifex worms ( tubifex sp)
pouch snails (gastropoda)
barrier islands
low, narrow, sandy islands that form offshore from a coastline --> protect coast, erosion
what protects land from erosion by sea?
primary and secondary dunes on gently sloping sand, barrier beaches
what are reasons for variation in amount of oxygen in water?
number of consumers (respiration)
number of producers (photosynthesis)
number of decomposers (bacteria can take high lots of oxygen)
temp (cold hold more)
turgidity (rough water dissolves more)
turbidity (how cloudy water is)
source zone
fastest flowing water
coldest
high turgidity
low turbidity
floodplain zone
shallow
flat with slow flow
warm
nutrient rich
low turgidity
high turbidity
lakes
during summer and winter, deep temperate zone lakes become stratified into temp layers that overturn
overturns
equalizes temp at all depths
what is brought from surface to bottom in a lake?
oxygen
what is brought from bottom to surface in a lake?
nutrients
thermodyne
layer btwn warmer and colder layer
what causes overturn?
changed in temp from change in seasons (fall and spring)
what seasons produce most defined thermoclines?
summer and winter
cultural eutrophication
human inputs of nutrients from urban and agricultural areas can accelerate eutrophication process
anthropogenic
human created/caused
standing (lentic) water
lakes, ponds, inland wetlands
flowing (lotic) systems
streams and rivers
littoral zone
near shore
light can still penetrate
v shallow
lots of plants (more food, high biodiversity, more hiding spots)
limnetic zone
not near shore
light kinda penetrate
top
profundal zone
middle
dark water
low biodiversity
benthic zone
decomposers
low light
oligotrophic (poorly nourished) lake
newly formed lake w small supply of plant nutrient input
rocky bottom
nutrients trapped in water
eutrophic (well nourished) lake
over time, sediment, organic material, inorganic nutrients wash into lakes causing excessive plant growth
inland wetlands natural services
natural sponges
provide variety of wildlife habitats
filter and degrade pollutants
reduce flooding and erosion by absorbing slowing releasing overflows
help replenish stream flows during dry periods
help recharge ground aquifers
natural sponge
absorbs and stores excess water
fresh water inland wetlands economic services
recreation
fish for food
tourism
jobs
migration banking
an agreement to restore whatever wetlands u ruin
specifically for wetland
restoration, creation, enhancement for unavoidable wetland losses
must occur in advance of development
helps to consolidate small, fragmented wetland mitigation projects into larger sites
generally approved by wildlife agencies
how to test water quality of river/lake
smell
color
bacteria in culture
turbidity
test nitrogen level and phosphate
test pH
examine what is living in it
organisms in which area must be able to tolerate the greatest differences in salt concentrations?
estuary