1 / 37

Biomes - PowerPoint PPT Presentation

  • Uploaded on

Biomes. Section #3: Grassland, Desert, and Tundra Biomes. Biomes of the World. found in climates that have less rainfall less rainfall = less species diversity although you might have less variety, you still might have high numbers of individuals in those species that are present.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about ' Biomes' - avi

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript


Section #3:

Grassland, Desert, and Tundra Biomes

General info

found in climates that have less rainfall

less rainfall = less species diversity

although you might have less variety, you still might have high numbers of individuals in those species that are present

General Info


these grasslands are located in tropical & subtropical areas near the equator

found in parts of Africa, India, Australia, and South America

overall receive little precipitation throughout the year – but there are periods of heavy rainfall followed by periods of drought


Vegetation of the savannas

contain grasses, scattered trees, and shrubs near the equator

plants must be able to survive prolonged periods without water

plants have horizontal roots systems to capture as much moisture as possible

grasses have long vertical leaves that expose less surface area to the hot sun

some savanna plants even lose their leaves during the dry season to conserve water

thorns & sharp leaves keep herbivores at bay

Vegetation of the Savannas

African savanna
African Savanna near the equator

Savanna fires

during the dry season, fires often sweep across the savanna burning the grasses and shrubs

this returns nutrients to the soil

plants quickly regenerate from the shallow root systems

Savanna Fires

Animals of the savanna

mostly grazing herbivores & the predators that feed on them burning the grasses and shrubs

some grazers have adopted a migratory way of life to follow the rains & find newly sprouted grasses & fresh watering holes

predators usually follow & stalk the migratory animals

savanna animals usually give birth only during the rainy season when more food is available to increase chances of survival

Animals of the Savanna

Competition in the savanna

herbivore species reduce the competition for food by eating vegetation at different heights


small gazelles – feed on grasses

black rhinos – feed on shrubs

giraffes – feed on tree leaves

Competition in the Savanna

Temperate grasslands

dominated by grasses, very few trees vegetation at different heights

hot summers, cold winters

moderate rainfall, 50-88 cm of precipitation per year

summer temps and lack of precipitation can make the grasslands susceptible to fires that commonly sweep across the lands

Temperate Grasslands

Temperate grasslands1

located on the interior of continents - include North American prairies, steppes of Russia & the Ukraine, and the pampas of South America

few natural temperate grasslands remain, most have been replaced by farms & grazing areas

located near mountains that block the grasslands from receiving much precipitation

Temperate Grasslands

Plants of the temperate grasslands

mostly perennials – prairie grasses & wildflowers American prairies, steppes of Russia & the Ukraine, and the pampas of South America

grass height depends on root depth

root systems are dense – designed to survive the periods of drought & also hold the rich soil in place

few trees can survive – little rain, fires, & constant wind thwart tree growth

Plants of theTemperate Grasslands

Grasslands American prairies, steppes of Russia & the Ukraine, and the pampas of South America

Animals of the temperate grasslands

grazers with large, flat teeth for chewing the coarse prairie grasses (bison & antelope)

burrowers like badgers & prairie dogs are protected underground from the weather & fires – also they burrow underground to escape predators

Animals of theTemperate Grasslands

Threats of the temperate grasslands

most fertile soil – so many people farm or graze the grasslands

grain crops do not have good root systems to hold the soil – leads to soil erosion

overgrazing leads to grasses being overeaten & trampled – soil cannot regenerate & becomes less productive

Threats of theTemperate Grasslands

The chaparral

type of temperate woodland biome grasslands

located in mid-latitudes (30° N or S)

near coastal areas with Mediterranean climates

warm, dry summers & mid, wet winters

too dry to support a forest, but more rain than a desert

receives enough precipitation to support vegetation that grows in bunches

The Chaparral

Chaparral grasslands

The chaparral plants

mostly low-lying evergreen plants that grow in dense patches grasslands

dominated by broad-leafed evergreen shrubs

plants include chamise, manzanita, scrub oak, olive trees, sage and bay herbs, plus piñon & juniper trees

The Chaparral Plants

The chaparral plants1

the small, leathery leaves retain water and contain oils that promote burning

well adapted to survive fires that kill competition for sunlight

can re-sprout from small bits of plant tissue

The Chaparral Plants

The chaparral animals

examples include quail, lizards, chipmunks, mule deer that promote burning

most animals utilize camouflage (shape or coloring) to blend into the environment

The Chaparral Animals

Threats to the chaparral

human development of the land for both commercial & residential use

humans like the area because of the mild climate year-round, proximity to oceans, and the large amounts of sunlight

Threats to the Chaparral


areas that receive less than 25cm of precipitation a year residential use

have little or no vegetation

extreme temperatures

located at several latitudes covering 1/5 of the Earth’s landmasses

located near large mtn. ranges that block the passage of moisture-filled clouds


Desert examples

hot deserts residential use

Sonora Desert, Arizona

Sahara, Africa


cold deserts

Gobi Desert, China



Desert Examples

Desert plants

all plants must be adapted to obtain & conserve water residential use

some plants even die & drop their seeds when the conditions get too dry

the seeds remain dormant until the next rainfall when they quickly germinate & grow

some can even survive when their water content drops to only 30% of their mass

Desert Plants

Other adaptations

succulents - such as cactuses – have thick fleshy stems & leaves to store water

waxy coatings to reduce water loss

sharp spines or thorns to keep thirsty animals away

plant roots that spread out just under the sand to absorb as much rain as possible

Other Adaptations

Desert animals

reptiles – like the Gila monster, rattlesnakes, & lizards – have thick scaly skin to prevent water loss

amphibians – like the spadefoot toad – survive the high temps by ESTIVATING (burying themselves in the ground and sleeping through the dry season)

desert insects & spiders are covered in body armor to retain water

most creatures are nocturnal to avoid the heat of the day

Desert Animals


located north of the Arctic Circle – have thick scaly skin to prevent water loss

very short summers

topsoil thaws out during the summer months creating a pattern of bogs & swamps across the land

below the topsoil is PERMAFROST – permanently frozen ground

constant winds


Tundra vegetation

dominated by tough grasses, lichens, herbs, & small shrubs that grow close to the ground

soil is extremely thin – wide, shallow roots anchor plants against the icy winds

lichens & mosses don’t even need soil to grow

plants try to absorb heat from the sunlit soil

Tundra Vegetation

Tundra animals

summer wet areas are breeding grounds for huge numbers of swarming insects like mosquitoes & black flies

many migratory birds feed on these insects

some herbivores are temporary summer visitors like caribou, deer, & moose plus the wolves that hunt them

Tundra Animals

Tundra animals1

some very well insulated creatures stay year-round, like arctic foxes, arctic hares, ptarmigan, & lemmings

although they may burrow to escape the cold, they are still active during the winter, often growing white fur to camouflage themselves in the winter snow

Tundra Animals

Threats to the tundra

very fragile biome arctic foxes, arctic hares, ptarmigan, & lemmings

simple food chains can be easily disrupted and lead to the demise of the other species

land is easily damaged & slow to recover

until recently, most areas were undisturbed by human activities – until oil was discovered

Threats to the Tundra

Threats to the tundra1

oil exploration, extraction, & transport has been particularly disruptive to plants and animals

pollution from spills or leaks of oil & other toxic materials can lead to the poisoning of food & water sources

Threats to the Tundra

Compare particularly disruptive to plants and animals