Biome

● Biome - A group of ecosystems that share similar climates and typical organisms

● When we talk about biomes, we typically mean LARGE areas.

Living or Nonliving?

● Biomes are determined by two factors: ○ Abiotic: non-living

○ Biotic: living

○ Is it living or nonliving?

• temperature,

• rainfall,

• type of plant,

• altitude,

• latitude,

• type of animals

Major Biomes

○ Tropical rain forest, tropical dry forest, tropical savanna, desert, temperate grassland, temperate woodland and shrubland, temperate forest, northwestern coniferous forest, boreal forest, and tundra

○ Each biome is defined by a unique set of abiotic (nonliving) factors- particularly climate- and characteristic plants and animals

Tropical Rainforest

○ Has more rain than all other biomes combined

○ Hot and wet year round

○ Species: ferns, woody vines, orchids, sloths, tapirs, jaguars, anteaters, monkeys, parakeets, piranhas

, anacondas

Tropical Dry Forest

○ Rainfall is seasonal rather than year round

○ Generally warm year-round, alternating wet and dry seasons

○ Species: tall deciduous (leaves fall off) trees, dense canopy, tigers, monkeys, elephants, termites, snakes, monitor lizards

Tropical Savanna

○ Also called Grassland

○ Spotted with isolated trees, small groves of trees, and shrubs

○ Frequent fires, large animals

○ Species: tall grasses, shrubs, lions, leopards, cheetahs, hyenas, elephants, giraffes, antelopes, zebras, baboons, ostriches

Desert

● Dry-annual precipitation of less than 25cm

● Organisms can tolerate extreme conditions

● Extreme temperature changes during the course of a day (very hot during the day and very cold at night)

● Species: cacti, mountain lions, gray foxes, mule deer, kangaroo rats, roadrunners, owls, hawks, tortoises, rattlesnakes, lizards

Temperate Grassland

○ Rich mix of grasses, plains and prairies

○ Periodic fires and heavy grazing by large herbivores

○ Warm to hot summers, cold winters, fertile soils

○ Species: coyotes, badgers, wolves, grizzly bears, rabbits, prairie dogs, cattle, owls, snakes, grasshoppers

Temperate Woodland and Shrubland

○ Semi-dry climate and a mix of shrub communities and open woodlands

○ Large areas of grasses and wildflowers and a lot of oak trees

○ Fires are a constant threat

○ Species: evergreen shrubs, coyotes, deer, rabbit, squirrels, hawks, lizards, snakes, butterflies, bobcats

Temperate Forest

○ Mixture of deciduous and coniferous trees

○ Deciduous trees lose their leaves in fall, cold winters

○ Species: deer, black bears, bobcats, conifers, flowering shrubs, herbs, mosses, ferns, raccoons, skunks, songbirds, turkeys, squirrels

Northwestern Coniferous Forest

○ Mild temperature, moist air from the Pacific Ocean provides abundant rainfall

○ Conifers, moss and flowering trees and shrubs are abundant

○ Species: fir, spruce, hemlock, and redwood trees, bears, elk, deer, owls, bobcats, weasels

Boreal Forest

○ Dense evergreen forests of coniferous trees-also called taiga

○ Bitterly cold winters, mild summers, high humidity

○ Mostly in the Northern Hemisphere

○ Species: lynxes, wolves, weasels, moose, beavers, migratory birds

Tundra

● Characterized by permafrost-a layer of permanently frozen subsoil

● Short, cool summers, small and crushed/short plants due to cycles of thawing and freezing

● Cold temperatures, high winds, short growing season

● Species: mosses, lichens, short grasses, shore birds, musk ox, arctic foxes, caribous, small rodents (can withstand harsh conditions)

○ Adaptations in plants and animals help different species survive under different conditions in different biomes

○ Plants and animals also exhibit variations in tolerance, or ability to survive and reproduce under conditions that differ from their optimal conditions

• Tolerance

• Plants and animals in Arizona for example, can tolerate temperatures that range from very very hot to below freezing

• Rain forest plants and animals will die if the temperature drops below freezing or rises above 34 degrees Celsius

Regions of North Carolina

● Different parts of our state do have different soil, landforms, river water, and temperatures.

● Because of the differences in these abiotic factors, there are differences in the biotic factors- what can live in each one

● So we divide North Carolina into three regions

Landforms

● Mountains: …Mountains!

● Piedmont: Rolling hills (means “foothills” in French)

● Coastal Plains: Low, flat to gently sloping land

● Elevation also affects temperature○ Higher elevations are typically colder

Soil

● Mountains: Rich, rocky soil

● Piedmont: Clay soil

● Coastal Plain: Rich, sandy soil

River Water

● Mountains: Fast, cold water

● Piedmont: Somewhat slower and warmer water

● Coastal Plain: Slow, warm, sometimes brackish water

Ecosystems

● Soils, water, and temperature combine to create various places where certain plants will grow (and others won't)

● That determines what animals can live there.

● An ecosystem is a system formed by the interaction of a community of organisms with their physical environment

Biodiversity

● Biodiversity - The number of different species in a given area

● The more diverse plant communities an area is able to support, the more diverse animals can live there too○ Think less competition for everyone

● North Carolina is also at the upper and lower ranges of many animals (Not too hot, not too cold)○ Because of this, North Carolina has a HUGE

diversity of species○ In fact, we have more species of salamander

than anywhere in the world!

Coastal Plains

● Sandy soil of the Coastal Plain is a great place for Longleaf Pine, and Red-cockaded Woodpeckers will only create their nesting cavities in mature Longleaf Pine forests.

Mountains

● Cold tops of our mountains is where spruce forests can grow, and that is the only place where you will find the Northern Flying Squirrel in our state

● However, we can look deeper into the diversity of different types of areas...

● Biodiversity of the biosphere ○ All the species on Earth

● …biome ○ All species in similar areas on Earth

● …ecosystem/community ○ All species in a smaller area on Earth

● …population ○ All the individuals of one species in an area on Earth

Genetic Diversity

● Genetic Diversity - The total number of genetic characteristics in a given population

● These variations serve as a way for a population to adapt to changing environment.

● Greater variation increases the chance that some individuals of that population will possess variations that are suited to the new environment. ○ They’ll live and pass on those traits to the next generation,

preventing extinction of their species!

Imagine:

● One individual has a mutation that makes it darker color than the rest of the population.

● After a volcanic eruption, so the cover is no longer pale yellow, but a dark.

● The darker individual will then survive in the new environment and reproduce more than the other individuals, passing on “dark color” genes to the next generation.

Variation in an Ecosystem

● Every organism has a role to play in its environment.

● This role, which includes where it lives in the environment, what it uses, what it eats, and who eats it, is called its niche.

● No two species can ever share the SAME niche.

Variation in an Ecosystem

● When a species is lost in a diverse ecosystem, then another species may take over its role…

● Or all the organisms that depend on it may die if there is not a diversity of organisms already in that ecosystem.

● But it takes a LONG time.

Loss of Biodiversity

● The greatest threat to biodiversity is habitat loss.

● Habitats (places where organisms live) are “lost” due to land use changes○ Agriculture

○ Urbanization

Habitat Alteration

● As the human population grows, habitats are altered

Habitat Fragmentation

● Fragmentation is the process that divides large ecosystems into smaller, isolated parts.

● As a habitat gets smaller, more and more species are affected.

● Smaller habitats -> less diversity -> less of a chance to recover from changes in the ecosystem

Overharvesting

● Overharvesting is the catching or removing from a population more organisms than the population can replace

Overharvesting: Plants

● Long leaf pine and white cedar forests were decimated in our state for the lumber industry.

Overharvesting: Animals

● Market hunting (commercial hunting) at the turn of the century exploited natural resources for profit.

● For instance, beaver were completely exterminated from the state, river otters were no where to be found in the western part of our state, it's estimated that only 10,000 deer were left, very few wild turkey were left, and black bear were found only in the deepest mountain valleys or thickets in Pocosins near the coast.

Overharvesting: Animals

● Then game laws were enacted to protect our game animals from over hunting by creating hunting seasons and limits.

● Black bear and white tailed deer have rebounded naturally, while river otter, beaver, and wild turkey were brought in from other states to repopulate areas of our state.

Invasive Species

● Native species ○ Organisms that naturally live in a certain area.○ Evolved in that area over time○ Typically co-evolved with other species that keep its population in

check through predation, competition or disease.

● Non-native species (exotic or alien species)○ Organisms introduced or moved to an area by humans where they

don’t naturally occur.○ Not necessarily harmful…○ Harmful ones are called invasive species

• Outcompete native species in a natural community or cause ecological or economic problems

• No natural controls to limit their population• Typically have a high rate of reproduction and tolerate a large variety of

conditions• Take over!