Aquatic Ecosystems: Biodiversity, Threats, and Conservation

Wetlands

Environmental feature California is losing.

Sources of pollution

What wetlands help indicate.

Sinking land in marshes

Threatens the existence of marshes as they can only survive at the top of the tidal frame.

Volunteer in your community

One way individuals can help wetlands.

Freshwater aquatic systems

Examples include groundwater, streams, rivers, ponds, reservoirs, lakes, wetlands.

Marine aquatic systems

Examples include salt marshes, seagrass beds, mangrove forests, kelp beds, coral reefs, oceans.

Estuaries

Where freshwater and marine systems meet.

Aquatic biodiversity contributors

Plankton, cyanobacteria, aquatic plants, fish, insects, invertebrates, reptiles, mammals, birds.

Known species of fish

About 25,000.

Medical uses from ocean materials

Include antibiotics, anticancer compounds, hypertension treatment, bone reconstruction, dental adhesives, viral encephalitis treatment.

Ecological importance of aquatic biodiversity

It recycles nutrients, purifies water, recharges groundwater, attenuates floods, and provides vital habitats.

Economic importance of aquatic biodiversity

Provides recreation, food (16% of global protein), raw materials like seaweed for pharmaceuticals and cosmetics.

Common stressors in aquatic ecosystems

Chemical, physical, biological.

Eutrophication

Overload of phosphorus or nitrates causing algae blooms.

Chemical stressors

Toxins, changes in pH and water chemistry.

Physical stressors

Light availability, water flow, temperature changes.

Biological stressors

Overharvesting, exotic species introduction, interspecies competition.

Aquatic plants coping with stress

Use air sacs, fermentative metabolism, anaerobic respiration.

Thermal stratification

Temperature layering prevents nutrient mixing and increases exposure for surface organisms.

Environmental factors affecting aquatic ecosystem health

Greenhouse gases, temperature, UV radiation.

Results of environmental feedback in aquatic systems

Lower salinity, more UV exposure, higher CO₂ levels.

Aquatic species lost in the last 200 years

More than 1200.

Mutations in invertebrates and amphibians

Indicate early signs of water contamination.

Primary human-caused stressors on aquatic ecosystems

Overfishing, habitat loss, invasive species, pollution.

Acoustic pollution

Sound travels farther in water; it disrupts whales' feeding, breeding, and migration.

International Union for the Conservation of Nature (IUCN)

Organization that tracks conservation status globally.

Most threatened vertebrates

Freshwater fishes.

Species supported by freshwater systems

More than 100,000 species.

Primary threats to freshwater ecosystems

Habitat loss, overfishing, pollution, invasive species, climate change.

Impact of habitat loss on freshwater ecosystems

Disrupts species populations and biogeochemical cycles.

Forestry practices harming freshwater systems

Reduced shade increases water temperature; fertilizers from replanting introduce excess nutrients.

Impact of overfishing on freshwater biodiversity

Leads to commercial extinction of species.

Types of pharmaceuticals found in freshwater

Antidepressants and birth control.

Effects of pharmaceuticals on aquatic life

They can cause mutations in fish.

Invasive species threat to freshwater biodiversity

They threaten biodiversity by competing with native species.

Causes of Wetland Loss

What are the causes of wetland loss? Drought, sea level rise, and urban development

Wetland Disappearance

How much of the world's wetlands have disappeared? More than half

Marine Biodiversity Factors

What are the main factors affecting marine biodiversity? Habitat degradation, sediment loading, coastal development, trawling, deep-sea mining, beach erosion

Importance of Beach Sand

Why is beach sand important to coastal ecosystems? It is pivotal to coastal health and helps prevent erosion

Beach Damage Causes

What human activity has caused the most beach damage? Anthropogenic construction

Groins Purpose and Failure

What is the purpose of groins and how do they fail? They trap sand to prevent erosion but increase erosion on the other side

Seawalls Purpose and Effect

What is the purpose of seawalls and their unintended effect? Protect property but cause large waves to break suddenly, increasing erosion

Imported Sand Erosion

Why does imported sand erode faster? It is finer and more easily carried away by water

Beach Drainage System

What does a drainage system do for beaches? Filters and pumps seawater offshore to manage beach stability

Beachsaver Module

What is a beachsaver module? Structure that becomes immersed in sand to slow erosion and increase sand accretion

Shortcomings of Beach Stabilization

What are the two major shortcomings of beach stabilization methods? Inability to regulate dynamic sand environment and failure to address root causes

Non-point Sources of Marine Pollution

What are examples of non-point sources of marine pollution? Sewage, agriculture, construction, ranches, cars, boats, and air pollution

Harmful Chemicals in Fish

What harmful chemicals have been found in fish? Mercury, lead, and cadmium

Climate Change and Marine Productivity

How does climate change reduce marine productivity? Prevents layer mixing, reducing upwelling/downwelling and biological productivity

Challenges in Protecting Marine Biodiversity

Why is protecting marine biodiversity difficult? Damage is often invisible, ocean is seen as infinite, no strong international agreements

Tragedy of the Commons

What is the tragedy of the commons in the context of oceans? Shared ocean resources are overused because no one owns them

Solutions for Marine Biodiversity

What are some solutions to protect marine biodiversity? Establish protected areas, integrate coastal management, reduce pollution, manage fisheries sustainably

Marine Mammal Protection Act

What is the Marine Mammal Protection Act and when was it established? A U.S. law passed in 1972 to protect marine mammals from human harm

1973 U.S. Endangered Species Act

What is the purpose of the 1973 U.S. Endangered Species Act? To protect and recover imperiled species and the ecosystems they depend on

CITES

What is CITES and when was it created? Convention on International Trade in Endangered Species, established in 1975 to prevent illegal wildlife trade

1976 Whale Conservation and Protection Act

What is the 1976 Whale Conservation and Protection Act? A U.S. law focused on conserving whale populations

1979 Global Treaty on Migratory Species

What is the purpose of the 1979 Global Treaty on Migratory Species? To conserve migratory species across international borders

1995 International Convention on Biological Diversity

What does the 1995 International Convention on Biological Diversity promote? Conservation of biodiversity and sustainable use of its components

U.S. Federal Agencies for Marine Protection

Which U.S. federal agencies enforce marine protection laws? US Fish and Wildlife Service, NOAA, and Marine Mammal Commission

Ineffectiveness of Marine Protected Areas

Why are many marine protected areas ineffective? They are too small to provide real protection

Exclusive Economic Zone (EEZ)

What is an Exclusive Economic Zone (EEZ)? A 200-mile zone where a country controls marine resource use

Integrated Coastal Zone Management (ICZM)

What is Integrated Coastal Zone Management (ICZM)? A strategy for managing coastal areas for sustainability

ICZM of Barbados

Research, coastal resource inventory, development review, and public education

Collapse of the Atlantic Northwest cod fishery

Technological advances, ecological ignorance, socioeconomic pressure, and government mismanagement

Marine Stewardship Council

Organization created in response to the cod collapse

Maximum Sustainable Yield (MSY)

The highest rate at which a species can be harvested without long-term depletion

Challenges of MSY management

Fish populations are hard to measure, quotas are underreported, and enforcement is weak

Harvesting one species at MSY

It can disrupt interdependent species and food webs

Optimum Sustainable Yield (OSY)

A more conservative approach that considers ecosystem health and multispecies interactions

Precautionary principle in fisheries management

If there's uncertainty, management should err on the side of caution to prevent harm

Fishery regulations to protect marine life

Use of special nets to reduce bycatch (e.g., turtles)

Key strategies to protect wetlands

Enact/enforce legislation, apply land-use planning, restore degraded wetlands, replace destroyed wetlands

Mitigation banking

Offsetting damage to wetlands by preserving, enhancing, restoring, or creating others (PERC)

PERC

Preservation, Enhancement, Restoration, Creation - approaches in mitigation banking

Invasive species in wetlands

Purple loosestrife

Species threatened by wetland loss

Bog turtle, black tern, canvasback duck

Agency responsible for wetlands regulation

EPA (Environmental Protection Agency)

Wetland delineation

A test to determine the boundaries between upland and wetland

Wetland delineation assessment

Soil type, shells, vegetation, and land usability

Tool for analyzing soil in wetland delineation

Munsell Soil Color Chart

1899 Rivers and Harbors Appropriation Act

Protects navigable waters from unauthorized alteration

1948 Federal Water Pollution Control Act

Initial framework to reduce water pollution

1972 Clean Water Act

Regulates discharges of pollutants into waters, including wetlands

1969 National Environmental Policy Act

Requires environmental assessments for federal projects

1996 Federal Agriculture Improvement and Reform Act

Links wetland conservation to agricultural subsidies

1973 Endangered Species Act

Protects species and their habitats, including wetlands

1998 Transportation Equity Act for the 21st Century (TEA-21)

Funds wetland restoration as part of transportation projects

1990 Coastal Wetlands Planning, Protection, and Restoration Act

Restores and protects coastal wetlands in the U.S.

1989 North American Wetlands Conservation Act

Supports conservation efforts for migratory birds and wetland habitats

Trey Dempsy's environmental concern

There are many toxins in the environment.

Trey Dempsy's role as an aquatic biologist

He monitors waterways and addresses environmental issues.

High number of fish in a waterway

It can indicate a healthy aquatic environment.

Michelle Woo Bowman's main focus

Finding where environmental problems come from and how to fix them.

Michelle Woo Bowman's associated program

The Clean Marine Program for San Diego.

Impact of the Clean Marine Program beyond San Diego

It has inspired similar programs in other states.

Best management practices according to Michelle Woo Bowman

Methods for boaters to be more environmentally friendly.