Biodiversity Overview and Importance

Biodiversity

• Includes genetic diversity, species diversity, and ecosystem diversity.
• The variety of life on Earth is called biodiversity.

Genetic Diversity

• The variation of genes within a single species.

Species Diversity

• Refers to the variety of living organisms (species) present on Earth.
• Approximately 1.7 – 2 million species have been formally identified.

Ecosystem Diversity

• Also called ecological diversity.
• The variety of ecosystems on Earth such as forests, deserts, grasslands, and oceans.

Importance of Biodiversity

• Humans depend on a rich variety of genes, species, and ecosystems.
• Biodiversity is used in agriculture, industry, medicine, ecosystem stability, science, genetic engineering, aesthetics, and ethics.

Aquatic Ecosystems

• Ecosystems within a body of water.
• Classified as freshwater or marine.

Marine Ecosystems in the Caribbean

• Mangroves
• Seagrass Beds
• Coral Reefs

Mangroves

• Located between the sea and land in areas inundated by tides.
• Dominated by trees partially submerged in coastal wetlands.
• Habitat for ~2000 species.

Functions of Mangroves

• Protects the shoreline from erosion.
• Serves as a fish nursery.
• Absorbs excess water.
• Filters water from the land.
• Encourages sediment deposition.

Seagrass Beds

• Important foraging ground for various fish species: grouper, grunt, snook, snapper, parrotfish, barracuda, and tarpon.
• Primary food source for turtles, manatees, urchins, and parrotfish.
• Fish nursery ground.

Functions of Seagrass Beds

• Buffers wave action to stabilize sediments and create clearer waters.
• Filters nitrates and phosphates from the water column.

Coral Reefs

• Found in warm, tropical, and subtropical oceans (equatorial region).
• Located in coastal, shallow waters.

Functions of Coral Reefs

• Habitat for many marine plants and animals.
• Protects the shoreline from erosion.

Abiotic Factors: Weather and Climate

• Weather refers to short-term changes in temperature, pressure, precipitation, and other atmospheric conditions at a specific place and time.
• Climate is the average weather of an area taken over a period of at least 30 years.
• Temperature and precipitation are the two key factors that determine climate.

Biomes

• Large, relatively distinct terrestrial regions characterized by similar climate, soil, plants, and animals regardless of their location.
• Climate and vegetation vary with latitude and altitude.

Major Biomes

• Tropical rainforest
• Savannah
• Desert
• Chaparral
• Temperate grassland
• Temperate deciduous forest
• Temperate rainforest
• Taiga
• Tundra

Tundra

• Also called "arctic tundra."
• Located just south of the arctic polar ice cap.
• Covered with ice and snow for most of the year.
• Bitterly cold.
• Characterized by permafrost.

Taiga

• Also called "swamp forest" or "boreal forest."
• Located south of the arctic tundra.
• Long, cold, dry winters with 6-8 hours of sunlight.
• Dominated by a few species of coniferous evergreens.

Tropical Rainforest

• Found near the equator.
• Warm temperatures.
• High precipitation.
• Thin, nutrient-poor soil.
• High biological diversity.
• Often lost to slash-and-burn cultivation and logging.

Deserts

• Receive very low precipitation.