Aquatic

• Aquatic ecosystem


  A community of organisms and the physical environment they inhabit in bodies of water, such as oceans, seas, rivers, lakes, ponds, and wetlands
• Aquatic ecosystem


  • Defined by factors such as water depth, flow rate, and salinity
  • Support a wide variety of life forms, including fish, invertebrates, plants, algae, and microorganisms, which interact with each other and with their environment in complex ways
• Criteria used to classify aquatic ecosystems

  • Salinity
  • Depth
  • Whether the water is flowing or standing
• Salinity

  • Measure of the amount of salts dissolved in water, expressed in parts per thousand (ppt)
  • Water with salinity between 0.5 and 30 ppt is called Brackish
  • Freshwater has a salinity of 0.5 ppt or less
  • Seawater has an average salinity of 35 ppt
• Photic zone


  The uppermost layer of an aquatic ecosystem where there is enough sunlight for photosynthesis
• Aphotic zone


  The layer below the photic zone where no sunlight penetrates and photosynthesis cannot occur
• Benthic zone


  The very bottom of a body of water
• Aquatic consumers


  Obtain the oxygen they need for cellular respiration from water taken in through gills, rather than breathing air
• Upper layer of aquatic ecosystem


  Tends to be warmer than deeper layer
• Flowing-water ecosystems


  Contain water that is in near-constant motion, such as in a river
• Standing-water ecosystems


  Contain water that does not move, or moves slowly, such as in a pond or wetland
• Importance of aquatic ecosystems

  • Biodiversity - Provide habitat for numerous species
  • Environmental stability - Act as buffers against storms, floods, and erosion, regulate water quality
  • Economic value - Support fisheries, aquaculture, tourism, and recreational activities
• Types of aquatic ecosystems


  • Marine ecosystems
  • Freshwater ecosystems
• Marine ecosystem


  The largest aquatic ecosystem, covering over 70% of the earth's surface, relatively more concentrated in terms of salinity
• Components of marine ecosystem

  • Ocean ecosystem
  • Estuaries
  • Coral reefs
  • Coastal ecosystem
• Ocean ecosystem

  Includes the Pacific, Atlantic, Indian, Arctic, and Southern Oceans, home to a variety of aquatic organisms
• Estuaries


  Meeting point of a sea and rivers, where the water is slightly more saline than freshwater and more diluted than the marine ecosystem
• Coral reefs


  Aquatic ecosystems made up of corals that form reefs, supporting a wide diversity of aquatic flora and fauna
• Coastal ecosystem


  Formed where land and water meet, dominated by plants and algae, home to a variety of animals
• Freshwater ecosystem


  Covers less than 1% of the earth's surface, broadly divided into wetlands, lentic, and lotic ecosystems
• Swamps and wetlands


  Marshy areas often covered in water, home to a variety of flora and fauna
• Lentic ecosystem


  Standing water bodies like ponds and lakes, home to floating and rooted plants, algae, and invertebrates
• Lotic ecosystem


  Characterized by rapid flowing water moving in one direction, home to a wide variety of insects and other aquatic species
• Functions of aquatic ecosystems

  • Facilitates recycling of nutrients
  • Helps to purify water
  • Recharges groundwater
  • Provides habitat for aquatic flora and fauna
  • Mitigates flood
• Aquatic biodiversity


  The rich and wonderful variety of plants and animals that live in watery habitats
• Marine biodiversity

  The variety of life in the ocean, including all animals, plants, and microorganisms
• Coral reefs are considered to be the most biologically diverse of all marine ecosystems, supporting an estimated 25 percent of all marine life and 32 of the current 34 existing animal phyla
• Fresh water makes up only 0.01% of the World's water and approximately 0.8% of the Earth's surface, yet this tiny fraction of global water supports at least 100,000 species out of approximately 1.8 million - almost 6% of all described species
• Freshwater habitats are incredibly diverse, with more than 400 large-scale ecoregions and thousand of rivers, lakes and wetlands. Freshwaters are also hotspots for biodiversity. They are home to at least 140,000 specialist freshwater species
• Food chains in aquatic ecosystems

  1. Algae/Phytoplankton (Producers)

  2. Zooplankton (Primary Consumers)

  3. Small Fish (Secondary Consumers)

  4. Larger Fish (Tertiary Consumers)

  5. Sharks or Seals (Apex Predators)
• Food webs in aquatic ecosystems

  1. Producers: Algae, phytoplankton, and aquatic plants

  2. Primary Consumers: Zooplankton, small fish, and herbivorous animals

  3. Secondary Consumers: Larger fish, crustaceans, and small predators

  4. Tertiary Consumers: Larger predatory fish, seals, and other marine mammals

  5. Decomposers: Bacteria and fungi that break down dead organisms
• Human impacts on aquatic ecosystems

  • Water pollution
  • Overfishing
  • Habitat destruction
  • Climate change
  • Resource extraction
• Conservation and management strategies for aquatic ecosystems

  • Establishing protected areas
  • Implementing regulations to control pollution and manage fishing practices sustainably
  • Adopting ecosystem-based management approaches
  • Engaging local communities in conservation efforts
  • Investing in research and monitoring programs