Lecture Notes: Human Disturbances to Mangroves and Wetlands

Objectives

• Describe human activities impacting wetlands and mangroves
• Practice describing solutions to environmental problems

Wetlands

• Definition: Areas where soil is submerged in water part or all year
• Emergent Vegetation: Plants with roots in soil, parts extend out of water
  • Adapted to submerged conditions to access oxygen

Importance of Wetlands

• Provisioning Services: Habitats for animals/plants used for food or raw materials
• Regulating Services:
  • Groundwater recharge: Filters pollutants, sequesters CO2
• Supporting Services:
  • Water filtration: Traps pollutants, prevents groundwater contamination
  • Pollinator habitats: Supports pollinators such as bees and butterflies
  • Nutrient recycling: Decomposes organic matter, enriching soil
  • Pest control: Habitats for pest-eating organisms
• Cultural Services: Tourism, educational research opportunities

Threats to Wetlands

• Pollution: Nutrient pollution, sediment, motor oil, pesticides, endocrine disruptors
• Development: Infilling for construction, loss of habitat and ecosystem services
• Water Diversion: Decreased water levels downstream leading to habitat loss
• Overfishing: Disrupts the food web, affects ecosystem stability

Mangroves

• Ecosystem Services: Estimated $800 billion value
  • Fuel and wood sources, coastal protection, water filtration, tourism attraction
  • Support for fish and shellfish, climate regulation through CO2 sequestration

Threats to Mangroves

• Logging and Deforestation: For development or subsistence
• Coastal Development: High-value real estate leading to destruction of mangroves
• Aquaculture and Agriculture: Shrimp farming, rice paddies replacing mangroves
• Pollution: Sediments and toxic solutions harming root systems

Solutions to Pollution

• Agricultural Solutions:
  • Cover crops to reduce runoff
  • Improved animal manure management
• Riparian Buffers: Vegetation alongside water bodies to filter runoff
• Human Sewage Management:
  • Septic tank upgrades
  • Biological waste removal using microbes

Practice Exercise

• FRQ 8.4: Describe an activity increasing phosphorus in estuaries and a reduction step