This document summarizes three groups of marine flowering plants: seagrasses, mangroves, and salt marsh grasses. Seagrasses grow in coastal waters and reproduce both sexually and asexually. Mangroves are woody trees found in tropical and subtropical intertidal zones that reproduce sexually. Salt marsh grasses are found along coasts and reproduce sexually and asexually. All three play an important role as nursery habitats for young marine organisms.

1. Marine Flowering Plants
Kingdom Plantae

2. Angiosperms
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Autotrophs
Have flowers used for sexual reproduction
Have pollen
Have seeds
Multicellular eukaryotes
Mostly on land-very few in the ocean
Evolved from land plants

3. Seaweeds (algae) vs. Flowering Plants
Photosynthesis
Structure/Support
Anchor
vs.
Water/Nutrient Absorption

5. Three Groups
• Seagrasses
• Mangroves
• Marsh grasses
• VERY IMPORTANT habitat for young marine
organisms – they all act like nursery grounds
for countless species!

6. Seagrasses
• Not true grasses
• Found in temperate & tropical coastal bays &
estuaries
• Subtidal = must stay underwater
• Prefer shallow, calm, clear waters
• Many species
• Zostera (eelgrass) is our type on Long Island
More about seagrasses: http://
www.flseagrass.org/ecology.php

7. Pictures of seagrass meadows

8. Seagrass Reproduction
• Sexually – stringy pollen carried away by currents
• Life cycle like land flowering plants
• Asexually – using rhizomes under the sediment

9. Mangroves
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Woody trees
Tropical & Subtropical
Intertidal=Not fully submerged
Often roots sticking out of the
water
• Several species – obviously,
none on Long Island

10. Picture of a Mangrove Forest

12. Mangrove Reproduction
• Reproduce sexually – with flowers
• “Pencil seed” germinates while
still attached to parent
– If it’s low tide: seed sticks in the mud
– If it’s high tide: seed is carried away
by current

13. Salt marshes
• Found in calm, sheltered bays on East and Gulf Coasts
of the US
• Intertidal
• Several species - our common ones are:
– Spartina alterniflora – salt marsh cordgrass
– Spartina patens – salt marsh hay
Virtual field trip through a salt marsh:
http://zottoli.wordpress.com/saltmarshes/spartina-alterniflora
/

14. Pictures of Salt Marshes

16. Marsh Grass Reproduction
• Sexually – flowers like flowering land plants
• Asexually - rhizomes

17. To Learn More…
• http://www.sglearnonline.com/seaweed-and-marineplants.html
• https://www.oceanclassrooms.com/ms101_u9_c1_sa_1
• Watch this:
http://www.oceanclassrooms.com/resources/storyline/uni
t9/MS101_U9_C1_SA_1/story.html