Biomes

• Definition: large region characterized by a specific kind of climate and certain kinds of plant and animal communities

• They can be freshwater, marine (saltwater), terrestrial, temperate, tropical, etc…

Biomes

• Temperature and precipitation are the two key factors of climate that determine biomes– Climate: the average weather conditions in an area over

a long period of time

• Most organisms have adapted to live within a particular range of temperatures – Would you find a polar bear living in Brazil? A naked

mole rat in Alaska? A salamander in the desert?– Adaptations for an organism’s habitat are important to

their survival!

Kinds of Biomes

• Terrestrial– Tropical – Temperate– High-Latitude

• Aquatic– Marine (Saltwater)– Freshwater

• Wetlands• Estuaries

Major Biomes of The World

Aquatic Biomes: Marine

• Examples: – Kelp forests, tidal pools, coral reefs, sea grass

beds, etc

• Animals adapted to deal with high salt concentrations, water temperatures

• Phytoplankton serves as the base of these biomes

• Large predators include whales, sharks, and dolphins

Aquatic Biomes: Marine

Aquatic Biomes: Freshwater

• Lakes, rivers, ponds, streams

• Wide variety of plants and animals– Fish, reptiles, amphibians, invertebrates, grasses

and shrubs

• As depth increases, less light available– no photosynthesis and no plants, decomposers

at the bottom recycle nutrients

• Estuaries– Area where freshwater mixes with salt water– Usually where a river empties into the ocean– Very productive ecosystems because they are

always receiving fresh nutrients from the river AND the ocean

Aquatic Biomes: Freshwater

Aquatic Biomes: Freshwater

• Wetlands– Area that is flooded or saturated for most of the

year• Bogs, marshes, swamps

– Transition zone between terrestrial and aquatic habitats

– Provide homes for LOTS of types of organisms– Act as “flood protection” for lower lying areas– Act as “buffer zone” or “filter” for pollutants

Aquatic Biomes: Freshwater

Aquatic Biomes: Freshwater

Terrestrial Biomes

• Major terrestrial biomes can be grouped by latitude– Tropical

• Near the equator

– Temperate• Between 30° and 60° latitude

– High-latitude60° and higher: polar regions

Terrestrial Biomes: Tundra

• Climate: long summer days and short periods of winter. Very little rain

• Plant Life: shallow rooted grasses, mosses, and lichens. Few trees because of lack of water and growing season

• Soil: shallow, most moisture not available since it’s frozen for most of the year--permafrost

• Animals: mosquitoes, lemmings, weasels, foxes, owls, hawks, oxen, caribou, reindeer

Terrestrial Biomes: Tundra

Terrestrial Biomes: Taiga• World's largest terrestrial biome

• Climate: long severe winters, short summers

• Plant Life: mostly evergreen trees with some deciduous trees

• Soil: thin and nutrient poor due to long term cold temperatures. High acid content due to fallen evergreen needles

• Animals: bears, foxes, lynx, wolves, caribou, moose, birds of prey

Terrestrial Biomes: Taiga

Terrestrial Biomes: Temperate Forest

• Climate: cool/cold winters and warm summers with plenty of rain

• Plant Life: deciduous trees in lower latitudes, evergreen trees in higher latitudes

• Soil: fertile, enriched with decaying litter

• Animals: squirrels, rabbits, skunks, birds, deer, mountain lion, bobcat, timber wolf, fox, and black bear

• Adaptations: bears and some rodents store up fat, and then hibernate during the cold winters. Birds and fish migrate to the south to escape temperatures that can be below zero

Terrestrial Biomes: Temperate Forest

Terrestrial Biomes: Tropical Rainforest

• Climate: warm temperature, lots of rain– Two seasons: wet and dry

• Plant Life: LOTS of different tree species, orchids, bromeliads, vines, ferns, mosses, etc

• Soil: thick wet mat on surface, most nutrients concentrated right at surface

• Animals: amazing amount of biodiversity– Layers of the forest contribute to biodiversity– At least HALF the earth’s species live in the rainforest– Still many, many undiscovered species

Terrestrial Biomes: Tropical Rainforest

Terrestrial Biomes: Grasslands

• Can be tropical (savannas) or temperate (praries/steppes/pamas)

• Climate: Dry. Usually experiences all 4 seasons

• Plant Life: Grasses and other non-woody plants; some trees

• Soil: Nutrient rich

• Animals: bison, coyotes, rodents, birds, reptiles, large herbivores

Terrestrial Biomes: Grasslands

Terrestrial Biomes: Deserts

• Climate: dry, can be temperate (Great Basin Desert and SW US) or tropical (Sahara, parts of S America)

• Plant Life: almost nonexistent, cacti. In temperate deserts wildflowers bloom seasonally

• Soil: dry, rocky, sandy

• Animals: coyotes, hawks, owls, snakes, lizards, spiders, scorpions– Animals adapted for life with little water, can get most of

the water they need from food they eat

Terrestrial Biomes: Deserts