3a Biomes and biographic regions PDF

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Biostratigraphy of Europe !

Lecture 3a

Biomes and biogeographic regions Classification - Biome = large areas of the earth surface that have similar climate and vegetation " • - largest recognisable subdivision " - Biogeographic region/province = area that contain similar flora and fauna " - Indicators " • The general form and lifestyle of plants eg desert plants are confined to regions " • Although species may differ they represent ecological equivalents " • Functional types of plants and animals e.g Reaukier’s plant life form - types of plants that are

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linked to different life and climates " World biomes are clearly linked to climate parameters "

Six basic vegetation structural types - Forest = dominated by tresses + generally continuous canopy " - Woodland = wide spaced trees " • = in shrubs, herbs and grasses " - Scrublands = continuous cover of shrubs " - Grasslands = grasses and herms " - Scrubs = widly spaced shrubs " • mainly barren " - Desert = sparse xerophytic plant cover wit mostly bare ground " - Holdrige life zone system —> " - The earth biomes = latitudinal and altitudinal gradients where there is a relationship with average annual temperature and annual precipitation "

Left -different biogeographical regions of Europe " Top - different Climates regions " 7 - mediteranian climate " 8- Temperate coastline climate " 9 - dry sepe semiarid climate " 10 - most continental " 11 - borel forest collate 12 - tundra

Biostratigraphy of Europe !

Lecture 3a

Artic (Tundra) Main influence on biodiversity are climate change and economic use of species (hunt, harvest)" Limited winter active species but large populations of summer active plants and animals with a large number of migratory plants and fish species " 12 = tundra Polar ice climates E - note on other map this was tip of Norway and on Iceland) " - Similtaneous influence of W Gulf stream waters and C artic waters affects the climate in all but the eastern most parts of the region " - Cold maritime climate dominated by polar (cP and mP) and artic (cA) air mass " - Winters = long + severe but mild -> oceans T = the overall T don’t fall as low as in the continental sub-artic continental interiors " - Very short mild season (not considered a summer) = some thaw " • This is a very short but intense growing season -> 24hr days " - Veg = frost resistant shrubs on rocky soils + peat bogs " • Variability in climate + diff. Annual patterns causes fluctuations to food access and limits reproductivity " - Low total annual precipitation - July = sea-ice covers melts and ocean water warms = ^ moisture content of local air mass = ^ in precipitation" - Evaporation is very low in the whole region " - The climates put extreme pressure on the plants and animals with a large region still under glaciation where permafrost is widespread with costal regions dominating the main habitat" Topography and Geomorphology - Wide range of landscapes (bare rock, swamis, glaciers, mountains, low plains) " - Most terrestrial ecosystems are a result of post- glaciation and vegetation colonisation is continuing in some of the volcanic ares where the ice is retreating " - Glaciers = imp. Features and the main process of landscape formation " - Freeze thaw = sentence erosion, changing topography and soil + surface patterns " Soil " - The North (tundra + polar desert) the ground is permenently frozen where the active layer of soil is constantly saturated in Sumer " - Crystals = soils with a frozen layer at the base - covers most of the region " - Permefrost exist where the arctic soil layer in the summer only thaws down to 1m in low arctic or less in the high arctic polar deserts " • This becomes discontinuous in the south -> transition to Borel climate " - Artic soils = you, infertile and poorly developed " - Tundra soils = thick layer of largely undecomposed oraninc matter " - Polar desert soils = pure sand and gravel (trace organics) " - Artic Camisoles brown soils = most developed and fertile soils found in sheltered areas on warm well drained sites with a deep active areas " - Not covered in glaciation = deeper organic soils esp. in wetter areas " - New soil is also being made by volcanics ash and lava " 2

Biostratigraphy of Europe !

Lecture 3a

Alpin Examples: the Alps, the Scandes, the Pyrenees, the Carpathians, the Rhodopes, the Urals, the Caucasia and the Dinaric Alps. Nature " - Biographic region exhibits and extreme fauna and flora and a high Lebel of endemism " - Mountain areas are vulnerable ecosystems characterised by low productivity, slow response rates and isolation " - High alpine = dwarf willow, lichens, shrubs " - Middle -low = dwarf birch "

- Climate change = low altitude species move upwards and highland species may = extinction" - Refuge for large carnivore and herbivores where the population has increased -> reintroduction " • Wolverine (Gulo gulpo) main habitat is the mountains " • Brown bear (Ursus arctos)= rarest animal -> habitat destroying (deforestation, agriculture) •

and hunting " The lynx (lynx, lynx) and the (canis lapis)

Alps Climate = influences the climate of central europe " • western mountain peeks area severe barrier for winds over long distances " • Peeks allow for sufficient rainfall at edge = rich grasslands and deciduous forests " • rainfall in the valleys is significantly lower = steppe and conifer forests (dwarf birch) " • Annual and spatial distribution of rainfall = highly variable and increases with altitude " Soils " • Development of stratified soils characteristics is low -> low T and continuous rejuvenation of soil by erosion " • Low T also = low degradation of litter- fall; humus is accumulating " • Acid soils occur in the sub-alpine zones -> limestones. " Scandes " - Defined as the area above the lower fringe of the birch forest " - Covered by ice during the last glaciation, species has to immigrate from the south " - Very few endemic species " Climate " • Climate factor structuring biodiversity = temperature, humidity and their relationship to the length of snow - free season " • Mean summer T - 6-10C - lower than the levels at the oceans " • Increasing latitude + ocean nearby creates different climate zones " - Gulf stream causes it to be relitivly mild " • Growing season = number of days above 5C = large variation occurs " Forest cover most of is area but dense gasses occur in drier climates"

Soil - Naturally high fertility soils " - Show a note-south gradation where decreasing moisture surplus results in less intense leaching = true podzols convert to grey and Camisoles brown forest soils " - Camisoles Brown forest soils = greater organic content and higher natural fertility " - Peaty swamp soils = lake areas + poorly drained valleys - imp in the north " - Foot hills of the Alps in the south contain sedimentary material form erosion of alps " - Most fertile soils = developed on losses (unstratified, fine-grained earth) blown south from glacial and fluvioglacial deposits " - Dependant on the climate conditions + geology nature of the strata " - Chernozems (central Ukraine) = most fertile soils in the wold developed on alluvial sed common on flood plaines " - Wetlands have been reduced - some large bogs and mires still occur in the central + eastern parts " Nature " - Permanelt grasslands are widespread but this is decreasing " - Forest area is increasing - natural forest = coniferous but coniferous forest dominates some A" • Little natural old forests " - Understory of the beech forests with spring genophytes that utilise the sun before the cover of the canopy%

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Biostratigraphy of Europe !

Lecture 3a

Atlantic Closely interacting with the boarding Alantic ocean + the North Sea. Has ilands and long coastlines " Topography and geomorphology - Low lying coasts are connected with shallow water/ lagoons where large land is vunerable to sea level changes " - Rocky coasts = varied fjords and rias, peninsulas and islands " Climate (8 = Temperate - marine west- coastline climate (Cfb, Cfc) - Mild and humid but exposed heavily to westerly wind at the coast + tidal movement are heavy" - Strongly influenced by the tropic part of the alantic ocean and along the Gulf stream => oceanic climate with moderate - mild T and high Precip + H humid - Winter precipitation maximum " - Prevailing westerly from large oceans = freq. cyclonic storm wit cool, moist mP air mass =abundant precipitiation esp. when enhances by orography effect" - Influenced by subtropical high pressure in summer but not strongly = drier summers > winter" - Maine influence = milder T than inland locations + small annual T range" - High levels of rainfall occurs up to 3000mm which causes leaching of the soils and feeds the bogs + moors along with the raid bogs " Soil - Camisoles, podzol and histosols -> high precipitation = uniform + well-developed humus" - Camisoles found all over except the note " - Podzols (acidic soils) are the characteristic soil " - Peet formations occur in the most humid parts " - Luvisols and fluisols are wide spread int he southern areas " - Shallower ranked soils found in the most southern areas " - Bogs + ferns with trees -> high precipitation" - Salt marshes in coastal low lying areas " - Reclamed land from the seam = sandy with more fine grained silt and fertile - initially saline but high precipitation + fresh water flooding = rises it way but it may remain salty at depth " Nature " - Mainly deciduous forests with conifers on higher ground with poor soils " - Natural forests are dominated by oak trees and mixed with birch " - native conifers = Scots pine in harsh conditions and nutrient poor soils + Yew on limestone " - Local migratory birds " - Most large animals are extinct "

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Biostratigraphy of Europe !

Lecture 3a

Mediterranean Topography and geomorphology - Hilly mountainous landscapes with inland plateaus between low mountain ranges " - Meeting point of 2 plates = tectonic and volcanic activity = in complex morphology + geology" Climate 7 = Mediterranean climate (Csa, Csb) - Warm with hot summers and mild winters - arid and deserts increasing with water more scarce" - Annual T cycle is week -> costal location " - Summer is very dry - 0mm for 4 months " • -> Dry continental tropical Air dominates " - Precipitation rises in the rainy winter seasons " • -> subtropical high pressure cells weaken + move down to equator and moist mP air mass invades = wave cyclones" • Drought in west = 2 months | east = 5-6 months " - Subtropical high pressure cells move polewards they enter this region" - Local scale = pronounced climatic difference over short areas -> slope, explosion, distance from sea, steepness and parent top type " - Short spring and autumn are critical periods for plant growth " Soil - Soils are low in humus (organic content) and the erosion risk is high in most areas " - Few lakes and bogs with the area covered by mires reduced " - Limestone is widespread and parental material for many local soil types " - Ferugineous brown “terra rossa” soils are common " - Rich in minerals by poor in humus - associated with garrigue habitat " - Siliceous souls = maquis habitat " - Alluvial soils of costal plains is the richest arable land " - Dry climate + topography+ lack of human = constant risk of erosion esp if there is no protective vegetation. Overgrazing, deforestation, surface disturbance on dry slope ground = ^ risk " Nature " - Large number of indigos species " - Highest number of endemics as well as wild ancestors to cultivate plants " - Imp wetlands for migratory birds " - Wolf and wild cats have spread by lynx is close to extinction " - veg= survives droughts - shrubs and trees produce small, hard/thick leaves that are water resistant to transpiration (Evergreen sclerophylls) and the strawberry tree" - degradation to open veg in many parts (garrigue) " - Conifer forests (pinus ssp.) in mountainous ans costal sandy soils " - Grasslands in areas with...