Key Marine Habitats Flashcards
What are MANGROVES?
Terrestrial plants which grow in permanently salty water (in tropics, near equator)
They buffer tropical shorelines from erosion and they filter runoff
Describe a MANGROVE GROWTH ENVIRONMENT.
Anoxic soil which causes hydrogen sulphide to be produced from mangroves
High salinity from evaporation
Describe PHYSICAL MANGROVE ROOT ADAPTATIONS.
Shallow root system that is widespread or perpendicular to the trunk
Elongation in Rhizophora, aerial/stilt roots
Branching anchors to secure against wave action
Describe MANGROVE ADAPTATIONS FOR SALINE SOILS.
Water drawn in against osmotic pressure
Root systems build up negative hydrostatic pressure by transpiration to counteract the uptake of salt water
Leaves have hairs to precipitate the droplets of salty water
What is SEAGRASS?
They are monocotyledonous with strap-like leaves
Can live intertidally or sub-tidally (mostly here)
Diversity of species decreases as you move further away from the tropics
Describe SEAGRASS GROWTH ENVIRONMENT.
Mud and sediment
They help other organisms by reducing turbidity, stabilising sediment and trapping sediment to increase light penetration
What is special about SEAGRASS PHOTOSYNTHESIS?
Needs high levels of light
No stomata instead pores in the thin cuticle absorb CO2
CO2 levels are low mostly found as bicarbonate so seagrasses have adapted to use that as a source
Describe seagrass LEAF PHYSIOLOGY.
Single layer of chloroplasts in the epidermis
Large gas pockets containing oxygen-enriched gas
Name the SEAGRASS ECOSYSTEM SERVICES.
Food for marine vertebrates
Eco-tourism
Coastal protection
Global warming mitigation
Fish nurseries
Carbon sequestration
Why are seagrass ecosystems THREATENED?
Fungal wasting disease
Reduced water quality
Coastal development
Mechanical damage
