Chapter 54- Ecology and Ecosystems

Recognize the levels of ecological inclusion: 

organism -> population -> community -> ecosystem -> landscape -> biosphere

Be able to describe abiotic factors influencing terrestrial biomes

• energy (usually solar),

• temperature

• water

• inorganic nutrients

• oxygen availability

• wind/fire

Define climate and how it determines the times of biomes across the planet, how communities are distributed

climate: weather conditions found on an area (long-term)

weather: short term atmospheric conditions of temperature, precipitation, sunlight and wind

how does it determine the times of biomes across the planet:

Energy from the Sun: The amount of solar energy received by Earth drives temperature patterns and plays a central role in shaping climate. 

Planet’s Movement in Space: Earth’s axial tilt and its orbit around the Sun cause seasonal variations in climate. 

Latitude: Latitude plays a crucial role in climate patterns. As mentioned, areas closer to the equator (low latitudes) receive more direct sunlight and are typically warmer, leading to tropical biomes like rainforests and savannas. At higher latitudes (closer to the poles), the Sun’s energy is less direct, and temperatures are colder, resulting in biomes like tundras and boreal forests.

The uneven heating of Earth’s surface (due to the Earth’s spherical shape) leads to differences in air pressure, which creates wind patterns. These wind patterns are instrumental in shaping climate and biomes.

Demonstrate how uneven heating of the equator influences moisture evaporation and precipitation in the form of rain and leads to the greatest biodiversity.

Uneven heating at the equator causes the Sun's rays to be more direct, leading to:

• Warm temperatures and intense heating of the Earth's surface. 

• Warm, moist air rises from the surface due to convection.

Evaporation: Warm temperatures cause high evaporation from oceans and land, adding moisture to the atmosphere.

Rising air: As the warm, moist air rises, it cools, causing the moisture to condense into clouds.
Precipitation: The condensed moisture falls as rain, leading to daily rainfall in the equatorial region.

This cycle of evaporation, condensation, and precipitation creates ideal conditions for tropical rainforests:

• High rainfall and warm temperatures year-round.

• Dense vegetation supports a wide range of species.

High biodiversity: The stable climate, abundant water, and layered habitats support the greatest biodiversity on Earth.

Explain how air descending away from the equator is so dry that it reabsorbs water from the lower latitudes (30°), generating deserts.

Descending air: Air from the equator rises due to intense heat, cools at higher altitudes, and then descends around 30° latitude (both N and S).

Dry air: As this air descends, it warms up, causing it to lose moisture, making it dry.

Reabsorption of moisture: This dry air has already absorbed moisture from lower latitudes, preventing rain and creating arid conditions. This is why deserts are commonly found at these latitudes, such as the Sahara and the Arabian Desert.

Explain how climate shapes biomes, which are often characterized by their vegetation, and what effect vegetation has on life in a biome.

Climate determines the temperature and precipitation patterns of an area, which directly influences the type of biome that exists.

Vegetation is a key characteristic of biomes because:

• It provides food and habitat for animals.
  
  

• Different vegetation types (like grasslands, forests, or deserts) shape the communities of animals that can survive there.
  
  

• For example, cacti in deserts are adapted to conserve water, while trees in rainforests have tall canopies to capture sunlight.

Understand how the prevailing winds [trade winds (east to west) and westerlies (west to east)] contribute to weather patterns.

Trade Winds (East to West):

• Located between the equator and 30° latitude, these winds blow from east to west, pushing moist air toward the tropics.
  
  

• They help bring moisture to tropical rainforests, leading to high precipitation in those regions.

Westerlies (West to East):

• Found in the mid-latitudes (30° to 60° latitude), these winds blow from the west toward the east.
  
  

• They bring moisture from oceans to continents, influencing temperate climates and contributing to rainfall in forests and grasslands.

Understand how ocean currents effect regional climates.

Ocean currents: Water in oceans moves in currents that distribute heat across the planet.

• Warm currents, like the Gulf Stream, can raise temperatures in coastal regions, making them warmer.
  
  

• Cold currents, like the California Current, can lower temperatures and reduce precipitation, leading to cooler, drier conditions.
  
  

These currents affect local climates by regulating temperatures and influencing precipitation patterns, making coastal areas milder or drier.

Understand how landforms effect local climate and what a rain shadow is.

Landforms like mountains affect local climate by blocking air movement.

Rain shadow effect:

• When moist air rises over a mountain range, it cools, loses moisture as precipitation, and creates a wet windward side.

• On the leeward (downwind) side, the air descends, warms, and becomes dry, creating a dry area (rain shadow) on the other side of the mountains.

• This is why areas like the Mojave Desert exist on the leeward side of mountain ranges.

Describe the types of terrestrial biomes (precipitation and temperature) – where are they and what types of plants/animals are characteristic?

Tropical Rainforest:

• High precipitation and warm temperatures year-round.

• Plants: Lush trees, vines, and shrubs.

• Animals: Monkeys, jaguars, birds like toucans, and insects.

Desert:

• Low precipitation, high temperatures.

• Plants: Cacti, succulents.

• Animals: Snakes, camels, lizards, small mammals.

Temperate Forest:

• Moderate precipitation, distinct seasons.

• Plants: Deciduous trees (oaks, maples), ferns.

• Animals: Deer, squirrels, birds, insects.

Grassland (Savanna):

• Moderate rainfall, but dry periods; warm temperatures.

• Plants: Grasses, occasional trees.

• Animals: Lions, elephants, bison, zebras.

Tundra:

• Low precipitation, cold temperatures.

• Plants: Mosses, lichens, small shrubs.

• Animals: Arctic foxes, reindeer, polar bears.

Boreal Forest (Taiga):

• Cold winters, moderate precipitation.
  Plants: Coniferous trees like pines, spruces.

• Animals: Moose, bears, wolves, owls.

Describe the types of aquatic biomes (characteristics, types, marine and freshwater) – where are they and what types of photosynthetic organisms/animals are characteristic?

• Characteristics: Saltwater, high biodiversity, include oceans, coral reefs, and estuaries.

Oceans:

• Plants: Phytoplankton (primary producers), seaweed.

• Animals: Fish, sharks, whales, dolphins, and sea turtles.

Coral Reefs:

• Plants: Algae, corals.

• Animals: Coral species, fish, sea anemones, mollusks.

Estuaries:

• Plants: Mangroves, salt-tolerant plants.

• Animals: Crabs, fish, birds, mollusks.
  
  

Freshwater Biomes:

Lakes and Ponds:

• Plants: Aquatic plants like lilies and algae.

• Animals: Fish, amphibians, insects

Rivers and Streams:

• Plants: Water plants, riparian vegetation.

• Animals: Fish (salmon, trout), amphibians, otters.

Wetlands:

• Plants: Marsh grasses, cattails, reeds.

• Animals: Frogs, birds, turtles, alligators.