temperate grasslands
TRANSCRIPT
![Page 1: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/1.jpg)
Grassland Biomes
location, structure and functions
![Page 2: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/2.jpg)
The 8 major biomes ofthe world
![Page 3: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/3.jpg)
The temperate grassland biome
Prairies of North America
Pampas of South America Veldt of
South Africa
Russian / Mongolian Steppes
AustralianBush
Canterbury Plains, NZ
![Page 4: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/4.jpg)
Steppe terrain in Russia and Mongolia• Undulating land dominated
by grasses• Large trees and shrubs are
mainly absent
![Page 5: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/5.jpg)
Steppe climate
What do you think the general climate is likethroughout the year and why? (think aboutfactors such as latitude)
Cool temperate climate for steppe grasslands(warm temperate climate for Veldt)
![Page 6: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/6.jpg)
Steppe climateWhat annual temperature range would you expect and why? (think about factors such ascontinentality)
Mean annual temperatures ranging from –15 inwinter to +20 in summer. Continental interiorresults in low temperatures during winter.
![Page 7: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/7.jpg)
Steppe climateHow important would you think precipitation isfor grassland biomes? Why? Would they behigh rainfall biomes? Why / why not?
Precipitation is a dictating factor on grasslandbiomes and grass type – more rain generallymeans taller grasses. Low precipitation (notenough for trees) of around 250-500mm per year. More precipitation in western steppethan in east as there are less rain-bearingwinds. 75% of all precipitation falls during thesummer months.
![Page 8: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/8.jpg)
Typical Steppe climate graph
![Page 9: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/9.jpg)
What problems could this factor of low precipitation bring?
Threats of drought and fire.
Steppe climate
![Page 10: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/10.jpg)
![Page 11: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/11.jpg)
![Page 12: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/12.jpg)
Temperate grassland soils
Chernozem (black earth) type
• Very deep, dark in colour with fertile upper layers• Nutrient rich from decay of surface matter in winter and
due to decay of deep, wide-branching roots – especially important for recycling of Ca.
• Approx 2m-deep grass rooting system helps keep the soil structure stable and intact (tightly-knit ‘sod’) reducing soil erosion and protecting underground stems and buds from winter frost and snow.
• Roots reach right down to the water table so there is a net upward movement of water.
• Ideal soils for farming but prone to wind erosion if ecosystem balance is not maintained.
![Page 13: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/13.jpg)
A Horizon 0-50cmsOrganic matter on top. Strong drying action by winds. Crumbly black topsoil. Matted, random root network with accumulation of mull humus and bases Ca, Ng, Na, K and some Fe, Al and Si. Grasses extract and return minerals. Many biota such as earthworms – nutrient mixing and aids drainage. B1 Horizon 50-100cmsFine vertical roots. Slight leaching of nutrients especially after spring snow melt and summer storms. Loess
B2 Horizon 100-160cmsCalcification occurs - nodules of CaCo3 form. Loess
C Horizon 160-200cmsweathered parent rockLime-rich parent rock 200cms
![Page 14: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/14.jpg)
Last lesson …• Where are the major areas of grassland biomes to be found?
• In terms of climate, what type of biome is Steppe?
• What did we find out about the climate in the Steppe biome?
• What type of soil is generally found in this area?
• Are these soils infertile? Why / Why not?
![Page 15: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/15.jpg)
Why no trees?
• Thick grass cover – prevents tree seeds from taking hold.
• Low precipitation inhibits tree growth.• Fire destroys any trees that may take hold –
underground stems and buds of perennial grasses not affected by fire (as opposed to trees and shrubs that have above-ground stems and buds).
• Grazing animals quickly destroy emerging shrubs and sapling trees.
• Grasses are hardy and quick growing.
![Page 16: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/16.jpg)
Steppe biodiversity
Low flora and faunadiversity when comparedwith tropical grasslandssuch as savanah.• Blue gramma and buffalo grass• Sagebrush and speargrasses
![Page 17: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/17.jpg)
Flora
What advantages do you thinkthese grasses have for survival inthe environment that they live in?
• Narrow, spine-like leaves• Waxy or downy surfaces• Long, water-seeking roots• Below-ground stems and buds• Seeds easily dispersed by wind• Some grasses and their seeds release
inhibitory chemicals
![Page 18: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/18.jpg)
FaunaLower biodiversity thantropical grasslands …
Small mammals(mainly rodents) • Gophers• Rabbits• FoxesOther mammals• Goats, antelope• HorseAlso• Reptiles• Birds• Many insect varieties
![Page 19: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/19.jpg)
GPP and NPP in temperate grasslands
• Gross primary productivity is the amount of energy trapped in organic matter during a specified interval at a given trophic level.
• Net primary productivity is the amount of energy trapped in organic matter during a specified interval at a given trophic level less that lost by the respiration of the organisms at that level.
![Page 20: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/20.jpg)
Tropical rainforest – 15000 Kcal/m2/yr
Comparative NPP rates in different biomes
Temperate forest – 5000 Kcal/m2 /yr
Temperate grasslands – 2000 Kcal/m2/yr
Desert – 500 Kcal/m2/yr
![Page 21: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/21.jpg)
Nutrient Cycling
• In addition to energy, ecosystems also contain cycles of nitrogen and other plant nutrients, such as phosphates and potassium.
• The pattern of plant nutrients can be shown as a diagram. Nutrients are derived from weathered rock or in dissolved in rainfall and they may be lost from the system by leaching, in runoff or through harvesting of crops.
• Most nutrients are recycled within the system through plant uptake, leaf fall (and other “fallout” from plants and animals) and decomposition.
• Nutrients are stored in the biomass, the litter and the soil in variable quantities depending on the type of ecosystem and seasonal changes.
![Page 22: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/22.jpg)
Mineral recycling
![Page 23: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/23.jpg)
![Page 24: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/24.jpg)
L
B
S
B
L
S
Tropical rainforest Steppe nutrient storage nutrient storage
![Page 25: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/25.jpg)
S
B
L
Input dissolvedin rainfall
Release as litter decomposes
Uptake byplants
Loss in runoff
Fall out astissues die
Input weatheredfrom rock
Loss byleaching
![Page 26: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/26.jpg)
![Page 27: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/27.jpg)
![Page 28: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/28.jpg)
![Page 29: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/29.jpg)
![Page 30: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/30.jpg)
![Page 31: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/31.jpg)
![Page 32: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/32.jpg)
![Page 33: Temperate Grasslands](https://reader034.vdocuments.us/reader034/viewer/2022050613/5882e87f1a28ab33258b78a9/html5/thumbnails/33.jpg)