Climate and Terrestrial Biodiversity

Hoh Rainforest (140 170 inches rainfall per year)

CLIMATE: A BRIEF INTRODUCTIONWeather is a local areas short-term physical conditions such as temperature and precipitation.Climate is a regions average weather conditions over a long time.Latitude and elevation help determine climate.

Solar Energy and Global Air Circulation: Distributing HeatGlobal air circulation is affected by the uneven heating of the earths surface by solar energy, seasonal changes in temperature and precipitation.

Ocean Currents: Distributing Heat and NutrientsOcean currents influence climate by distributing heat from place to place and mixing and distributing nutrients.

Effects of Global WarmingAlter precipitation patternsShift areas we can grow cropsRaise average sea levelsChange areas where some types of plants and animals can live

Topography and Local Climate:Land MattersInteractions between land and oceans and disruptions of airflows by mountains and cities affect local climates.

BIOMES: CLIMATE AND LIFE ON LANDDifferent climates lead to different communities of organisms, especially vegetation.Biomes large terrestrial regions characterized by similar climate, soil, plants, and animals.Each biome contains many ecosystems whose communities have adapted to differences in climate, soil, and other environmental factors.

Polar iceEquatorTropic ofCapricornTropic ofCancerHigh mountainsPolar grassland (arctic tundra)Temperate grasslandTropical grassland (savanna)ChaparralConiferous forestTemperate deciduous forestTropical forestDesert

BIOMES: CLIMATE AND LIFE ON LANDBiome type is determined by precipitation, temperature and soil type

Mountainice and snowElevationTundra (herbs,lichens, mosses)ConiferousForestDeciduousForestTropicalForestTropicalForestDeciduousForestConiferousForestTundra (herbs,lichens, mosses)Polar ice and snowLatitude

DESERT BIOMESDeserts are areas where evaporation exceeds precipitation.Deserts have little precipitation and little vegetation.Found in tropical, temperate and polar regions.Desert plants have adaptations that help them stay cool and get enough water.

DESERT BIOMESVariations in annual temperature (red) and precipitation (blue) in tropical, temperate and cold deserts.

Desert Plant AdaptationsDrop their leaves during hot and dry spells to survive dormant stateSucculent plants fleshy plants store waterSome have deep roots to tap into groundwaterSome have widely spread, shallow roots to collect water during brief rain showersSpines to guard against predatorsWax coated leaves to reduce water lossGrasses and wildflowers store their biomass in seeds

Desert Animal AdaptationsSmallHide in burrows during day and hunt at nightDormant during periods of extreme heat and droughtInsects and reptiles thick outer coveringsInsects and reptiles feces is dry and a dried concentrate of urine to minimize water lossGet water from dew

Dry fecesDry urine

Saguaro (sah-WAH-ro)cactusNo leavesStore water and synthesize food in their expandable fleshy tissueReduce water loss by opening their stomata only at night to take up CO2Grow up to 50 feet tallLive up to 200 yearsGrow a few inches a yearBranches around 50 years

Why are desert ecosystems fragile?Soils take a long time to recoverSlow plant growthLow species diversitySlow nutrient cyclingLack of water

GRASSLANDS AND CHAPARRAL BIOMESVariations in annual temperature (red) and precipitation (blue).

GRASSLANDSGrasslands occur in areas too moist for desert and too dry for forests.

Savanna GrasslandsScattered clumps of treesAnimals farsighted, swift, stealthyLarge herds of hoofed animalsSeasonal droughtsOccasional fires

Temperate GrasslandsThe cold winters and hot dry summers have deep and fertile soil that make them ideal for growing crops and grazing cattle.

Temperate grassland

ChaparralChaparral has a moderate climate but its dense thickets of spiny shrubs are subject to periodic fires.

Chaparral

Arctic tundra

Why is the tundra a fragile biome?Short growing seasonSoil and vegetation recovers slowlyHuman activities leave scars that persist for centuries

FOREST BIOMESVariations in annual temperature (red) and precipitation (blue) in tropical, temperate, and polar forests.

Bromeliad

buttress

Rafflesia worlds largest flower which smells like rotting fleshDense vegetation = little wind

Rainforest depends on others to spread seeds and pollen

Tropical Rain ForestFilling such niches enables species to avoid or minimize competition and coexistStratification of specialized plant and animal niches

Temperate Rain ForestsCoastal areas support huge cone-bearing evergreen trees such as redwoods and Douglas fir in a cool moist environment.

Temperate deciduous forest

Taiga (Boreal) Forest

Long wintersConiferous trees Low plant diversityHigh soil aciditySoil nutrient poor

Taiga

MOUNTAIN BIOMESHigh-elevation islands of biodiversity Often have snow-covered peaks that reflect solar radiation and gradually release water to lower-elevation streams and ecosystems.

Tree line

Ecological Role of MountainsContain majority of worlds forestOften habitats for endemic speciesSanctuaries for animal species driven from lowlandHelp regulate earths climateAbout 75% of worlds freshwater stored as glacial iceCritical role in hydrologic cycle

Human impact tropical rainforest

Human impact on deserts

Human impact on grasslands

Human impact on forests

Human impact on mountains

The End

*******Figure 5.9Natural capital: the earths major biomesthe main types of natural vegetation in various undisturbed land areasresult primarily from differences in climate. Each biome contains many ecosystems whose communities have adapted to differences in climate, soil, and other environmental factors. Human ecological footprints (Figures 3 and 4 on pp. S12S15 in Supplement 4) have removed or altered much of the natural vegetation in some areas for farming, livestock grazing, lumber and fuelwood, mining, and construction.**Figure 5.11Natural capital: generalized effects of elevation (left) and latitude (right) on climate and biomes. Parallel changes in vegetation type occur when we travel from the equator to the poles or from lowlands to mountaintops.**********