tropical coasts Flashcards
outline some characteristics of coral reefs
- one of the most diverse ecosystems
- provide habitat structure and provide a range of niches
- ecosystem engineering species
- facilitate secondary biodiversity
what is an ecosystem engineering species
species which directly on indirectly influence the availability of resources to other species
what is subsistence fishing
fishing to feed ones own family with no profit or economy
what is artisanal fishing
small scale, local and traditional fishing
what is commercial fishing
fishing to sell for profit
how does society use coral reefs
- provide economic activity of $30 billion a year
- account for around 5% of world marine fisheries
- 6 million coral fisheries out of 22 million artisanal fisheries world wide
what are some examples of stocks and flows coral reefs are used for
1) tourism
2) habitat structure
3) reef biodiversity
4) shoreline maitenence
5) coastal protection
6) fisheries
how are coral reefs distributed
within 30 degrees of latitude of the equator with lower abundance on western margin of continents
what are corals
- living tissues on a calcium carbonate skeleton which is symbiotic with algae
- rarley grow deeper than 50m with an upper temp limit of degrees
what is a polyp
each coral colony is made up of polyps which secrete calcium carbonate skeleton at the base and can synchronise spawning
what are the different types of reef
1) fringing
2) barrier
3) Atoll
outline fringing reefs
found along the coast of the red sea, it is the most common and susceptible to terrestrial influences
outline barrier reefs
different coral communities between back reef slope and patch and the fore-reef
may sometimes form small islands with unclear formation
what is a atoll reef
found far from land rising from depths of 1000s of metres
most found in the indo-west pacific
clear waters and low nutrients
what are the different types of algae found in reefs
1) macroalgae
2) coralline algae
3) TURF algae
what are parrot fish and what is their effect of reefs
found in reefs and gain most energy from the cynanobacteria and infauna
- erode reefs
- expose new substrate for settlement of larvae
give some examples of other reef creatures
1) sponges
2) molluscs
3) crustacea
what are phase shifts on coral reefs
describes the change from one state - normally coral dominated to another
what can trigger phase shifts
- coral bleaching
- hurricanes
- crown of thorn star fish
- eutrophication
what are some human impacts on coral reefs
- climate change
- development
- eutrophication
- ship collisions
- overfishing
what are mangroves
- dicotyledonous woody shrubs which are confined to the tropics
- form dense forests
- dominate monospecific patches
- stabalise soil
how many true mangrove species are there
55 species, 20 genera and 16 families
what are some characteristics of mangrove tree environments
- indundated with tides
- waterlogged soils
- fluctuating salinity
- evaporation leads to hypersalintiy
how are mangroves adapted to waterlogged soil
1) buttress roots
2) knee roots
3) pencil and peg roots
4) prop roots
how do mangroves cope with salt
Na and Cl are concentrated in the vacuoles
exluded from cytoplasm
depositied in bark
salt glands on leaves
senescent leaves
what are some reproductive adaptations seen in mangroves
- vivipary = seed develops still attached to parent plant
- float horizontally for a month
what are some human impacts on mangroves
- deforestation
- agriculture
- aquaculture
- urbanisation
- pollution
what are some natural impacts to mangroves
stroms
tsunamis
