Biomes
This presentation is the property of its rightful owner.
Sponsored Links
1 / 37

Biomes PowerPoint PPT Presentation


  • 142 Views
  • Uploaded on
  • Presentation posted in: General

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.

Download Presentation

Biomes

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


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

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

Savannas


contain grasses, scattered trees, and shrubs

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


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


mostly grazing herbivores & the predators that feed on them

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


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

Example:

small gazelles – feed on grasses

black rhinos – feed on shrubs

giraffes – feed on tree leaves

Competition in the Savanna


dominated by grasses, very few trees

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


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


mostly perennials – prairie grasses & wildflowers

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


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


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


Similarities? Differences?


type of temperate woodland biome

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


mostly low-lying evergreen plants that grow in dense patches

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 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


examples include quail, lizards, chipmunks, mule deer

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

The Chaparral Animals


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

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

Deserts


hot deserts

Sonora Desert, Arizona

Sahara, Africa

Australia

cold deserts

Gobi Desert, China

Greenland

Antarctica

Desert Examples


all plants must be adapted to obtain & conserve water

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


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


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

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


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


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


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


very fragile biome

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


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


  • Login