Ecosystem #2: Seagrass Meadows

Ecosystem A community of living organisms in conjunction with the abiotic factors, interacting as a system.

Things to Ponder: What do you know about seagrass? Why do you think seagrass is important to an area? What is the difference between seagrass and seaweed?

Seagrass vs. Seaweed Seagrass – Vascular plant (xylem & phloem) Kingdom Plantae Seaweed – Macroscopic marine algae Kingdom Protista (not a true plant)

Number of Species Worldwide -- Seagrass Macroalgae (Seaweed) Number of Species Worldwide 55 5,000-6,000 Reproduction Have separate sexes Produce flowers, fruits, and seeds Produce spores Structure Evolved from terrestrial plants Have roots, leaves, and underground stems (rhizomes) that hold plants in place Relatively simple and unspecialized Holdfast anchors plant to a hard surface; does not possess roots extending below the surface

Why is good water clarity important? Seagrasses and algae need sunlight in order to photosynthesize Light availability determines depth they will grow

Patch – small area of seagrass Meadow – large area If conditions are optimal (light, water quality and minimal disturbance) the patches will join to form a meadow

Why are Seagrasses Important? Predator/Prey Demo

YouTube: Gary the Explorer! Divide your paper into 3 columns and label as follows: #1 – Why are Seagrasses important? #2 – Organisms that live in Seagrasses #3 – Threats to Seagrasses

Importance: Basis of the food chain Habitat Nursery for baby animals Provide oxygen Improve water clarity by trapping suspended particles Stabilize ocean bottom Slow down waves action and prevent erosion Support local economies *Epiphyte – planktonic organisms that settle on sea grass

40,420 acres in 1950 26,920 acres in 1996 *2016 sea grass mapping study by TBEP revealed 41,655 acres of healthy sea grass

Seagrass ID Divide a sheet of drawing paper into 3 sections Turtle Grass Manatee Grass Shoal Grass

For each Type of Seagrass: Common Name Properly written scientific name Detailed drawing (in color) Detailed description 6 points per seagrass

What are the coils on the turtle grass? Tube worm casings from a fan worm! Clockwise - Spirobis spirillum Counterclockwise - Spirobis borealis

Algae Classification (Seaweed) Phylum Chlorophyta (green algae) Phylum Rhodophyta (red algae) Phylum Phaeophyta (brown algae) *Red and brown are exclusively marine while green algae can be found in freshwater

Seaweed ID Divide each sheet of drawing paper into 3 sections Draw each of the different types of algae

Seaweed ID Part I: Part II: Color drawing Write down the bucket number Detailed description Part II: Identify: Phylum Common Name Scientific name (properly written) FYI – additional info about it

What caused sea grass in Tampa Bay to decline beginning in 1950? Bringing Back the Bay

The Decline Population increased More people lived near the bay More garbage ended up in the water More cars/trucks = air pollution # of Cargo ships increased at the Port of Tampa Oil & gasoline spills/leaks Dredging

More Nitrogen entering the Bay Sewage treatment plants & other industries allowed to dump untreated waste products into Bay No real gov’t control of water pollution before 1972

Current Conditions Tampa Bay now gains over 500 acres of sea grass per year due to restoration projects and improved water quality

Article: A Crisis for Crabs

Questions What problem does the article focus on? What was the impact of the problem? Describe the life cycle of a blue crab. How many are likely to survive to adulthood? Describe why scientists believe the blue crab population is down off the coast of Georgia. What role does the estuary play in that decrease? How could bioaccumulation play a role in this estuary food web?