Seagrasses pt. 2 & Kelp

Third Check-in Reminder: Submit third check-in today.
- Select any peer-reviewed article and summarize how you'll use it in your project.
- A few sentences should suffice if you are familiar with the paper.
Group Collaboration: Ensure you're actively engaging with your project group due to upcoming peer evaluations.

Value of Seagrass Ecosystems: Estimated value of over $555 billion due to their ecological services.
Human Interaction: Coastal activities significantly affect seagrass beds, especially from boating activities.
- Example: Boats running aground can destroy large areas of continuous seagrass, leading to patchiness.

Continuous vs. Patchy Seagrass:
- Continuous patches are likely to have higher reproductive success compared to patchy ones, influenced by conditions such as nearby disturbances (e.g. boats).
Factors Impacting Seagrass:
- Sedimentation
- Boat wakes causing disturbances
- Coastal construction contributing to nutrient influx and pollution
- Overfishing affecting species reliant on seagrass habitats (e.g. juvenile fishes, seahorses)
- Extreme weather events related to climate change can destroy seagrass habitats.
- Diseases: Seagrass wasting disease is known to affect populations heavily, especially in regions like Florida.

Habitat Loss: Reduced biodiversity due to the loss of habitats for various marine species.
Carbon Sequestration: Loss of seagrass leads to decreased ability to store carbon, impacting ocean acidification.
Fishery Decline: Essential fish species may relocate, leading to declines in both recreational and commercial fisheries.
Coastal Instability: Seagrass stabilizes sediment; loss can lead to increased erosion.

Grazers Impact on Health of Seagrass: Presence of grazers (like crabs and sea urchins) influences health:
- Without predators (e.g. sea otters), grazer populations can explode, leading to overgrazing and decreased health of seagrass beds.

Kelp Habitat Structure:
- Structure includes holdfasts, stipes, blades, and pneumatocysts.
- Found mostly in cold, nutrient-rich waters, particularly in regions with upwelling favorable for growth.
Zonation Factors:
- Light availability is the main factor influencing the distribution of kelp species.
- Nutrients, temperature, and wave action also affect growth and species diversity in kelp forests.

Example Species:
- Feather Boa Kelp: Shallow water, branched structure.
- Laminaria: Non-branched, single blade structure, deeper water.
- Bull Kelp: Large nematocyst for buoyancy, common in California.
- Elk Kelp: Antler-like structure, needs rocky substrate.

Reproductive Phases:
- Dominant phase is the sporophyte (what we typically see).
- Gametophyte phase is crucial for fertilization.
Importance of Detritus: A significant part of kelp ecosystems, supporting numerous higher trophic levels.

Overgrazing: Sea urchin population blooms, especially when predator balance (like sea otters) is disrupted, can lead to destruction of kelp forests.
Climate Change Impacts: Changes in water temperature and nutrient availability associated with climate phenomena (e.g. El Niño and La Niña) significantly affect kelp health and productivity.
Human Impact: Coastal pollution and habitat destruction from construction, fishing, and recreational activities pose serious threats to kelp forests.

Marine Protected Areas: Establish zones that limit fishing and protect marine habitats to allow for recovery of ecosystems.
Awareness and Education: Importance of informing the public about the ecological roles of seagrasses and kelp beds, promoting engaged citizen science.
Restoration Techniques: Include strategies like kelp transplanting, seed banking, and reducing nutrient inflows to restore damaged ecosystems effectively.