Living Coastal Environments

Summary

This lecture delves into the dynamic nature of coastal environments, exploring the biological and geological processes that shape coastlines. Key topics include wetlands and coral reefs, which provide crucial ecosystem services like buffering coastlines from storms and supporting marine biodiversity. The video highlights the threats these ecosystems face, such as coastal development, pollution, invasive species, and climate change, which contribute to coral bleaching and ocean acidification. The importance of coral reefs as nurseries for fish and their role in the economy is also discussed, along with ongoing efforts to restore these vital ecosystems.

Takeaways

• 🌊 Coastlines are dynamic environments, constantly changing due to tides, currents, wind, waves, and sea level changes, which contribute to the creation of various landforms.
• 🦠 Wetlands are biologically diverse and play a crucial role in protecting coastlines from storm surges, especially in hurricane-prone areas like the east coast of the United States.
• 🏝️ Coastal development threatens wetlands, which are valuable for both biodiversity and ecosystem services, creating a conflict between development and conservation efforts.
• 🌱 Salt marshes and mangrove swamps are types of wetlands adapted to specific environmental conditions, with salt marshes found on the U.S. east coast and mangrove swamps in tropical regions.
• 🐠 Coral reefs are created by corals, which are simple marine animals that build calcium carbonate skeletons, forming vital underwater habitats and supporting diverse marine life.
• 🐚 Coral reefs are biologically significant, providing habitat for a wide range of species, with many coral reefs acting as nurseries for fish.
• 🌍 Coral reefs support 25-35% of oceanic species, despite covering only 1% of the ocean floor, making them vital ecosystems for marine biodiversity.
• 💰 Reefs contribute to human economies, with industries like diving tourism generating millions of dollars in revenue, and providing essential services like storm surge protection.
• 🩺 Coral reefs may hold potential for future medical discoveries, as marine life in these environments could provide valuable resources for new treatments.
• ⚠️ Coral reefs face numerous threats, including pollution, coastal development, invasive species, destructive fishing practices like blast fishing, coral bleaching, and ocean acidification due to climate change.

Q & A

What are coastal environments and why are they considered dynamic?

Coastal environments are areas where land meets the sea, and they are considered dynamic because they are constantly changing due to natural forces such as tides, currents, wind, waves, and sea level fluctuations. These factors shape the landforms we see along coastlines.

How do wetlands protect coastlines from hurricane storm surges?

Wetlands act as buffers by absorbing and reducing the impact of storm surges. They provide protection by slowing down or dispersing the force of incoming water, which is particularly important in areas prone to hurricanes, such as the east coast of the United States.

What is the conflict surrounding coastal wetlands?

The conflict arises from the value of coastal wetland land for development versus the ecological importance of wetlands. Wetlands are often threatened by development because they are located near the sea, and developers see them as valuable land for building, despite the environmental benefits wetlands provide.

What is the difference between salt marshes and mangrove swamps?

Salt marshes are found in temperate regions, typically north of 30 degrees latitude, and form in estuaries where fresh and saltwater mix. They are home to plants adapted to salty, wet environments. Mangrove swamps, on the other hand, are found in tropical areas and are characterized by dense mangrove trees with long roots that anchor the trees in shallow coastal waters.

What are coral reefs and how are they formed?

Coral reefs are underwater structures made up of colonies of tiny marine animals called corals. These corals secrete calcium carbonate, forming hard external skeletons that over generations create large reef structures. Corals rely on a symbiotic relationship with algae for nutrients, which helps them build the reef.

Why are coral reefs important for marine biodiversity?

Coral reefs are crucial for marine biodiversity as they provide a habitat for a wide variety of species. Despite covering only 1% of the ocean floor, coral reefs harbor 25-35% of all oceanic species, making them essential for the overall health of marine ecosystems.

What ecosystem services do coral reefs provide to humans?

Coral reefs provide ecosystem services such as protecting coastlines from storm surges, supporting fisheries by acting as nurseries for fish, contributing to tourism industries (e.g., diving), and offering potential sources for new medicines. These services are economically and ecologically valuable.

What are the main threats to coral reefs worldwide?

The main threats to coral reefs include pollution (such as sewage and runoff), coastal development, invasive species, destructive fishing practices like blast fishing, coral bleaching caused by temperature changes, and ocean acidification due to excess carbon dioxide in the atmosphere.

How does ocean acidification affect coral reefs?

Ocean acidification occurs when excess carbon dioxide is absorbed by the ocean, lowering the pH levels and making the water more acidic. This reduced acidity harms marine organisms that rely on calcium carbonate to build shells and skeletons, including corals. This can impair reef formation and reduce biodiversity.

What efforts are being made to restore coral reefs?

Efforts to restore coral reefs include reducing carbon emissions, controlling pollution, and stopping destructive coastal development. Additionally, scientists are growing coral in controlled conditions to eventually reintroduce them to the ocean, helping to mitigate the impacts of climate change and preserve these vital ecosystems.