Geography 104 Final KU (Biomes)
Tropical Savannah (TrS)
Climate: the lion king biome- warm all year, but precipitation varies greatly, 6 months wet when ITCZ is in the locations hemisphere, 6 winter months dry when ITCZ is opposite of its hemisphere. Examples: the sahel, in Africa south of Sahara north of Congo basin, southern Africa, east Africa, India, southeast brazil, venezuela, colombia, australia, not found in high latitudes. Importance of fire: thunderstorm and dry season, lightening, strikes dead plants, cleans out the environment, protects against invasive species. Vegetation: xerophytes- xero means dry phytic means plant, plants adapt to dry conditions, scrophyllous Fire-mediated serotiny: serotinous plants only germinates when exposed to a specific external stimulus Animals: lions, elephants, cheetahs, hyenas, zebras, rhinos.
Biogeography
The study of geographical distribution of plants and animals
Biomes and Climate
Biome distribution is related to temperature and precipitation- generally large scale plant distribution follows climate
Needleleaf and Montane Forests (NF/MF)
Boreal- North, at a high latitude- cold due to latitude Montane-Mountain- cold due to altitude Climactic- very cold due to high latitude and altitude Where the forest are found: Boreal- found in Canada, Scandinavia, and Russia. Montane Forests- Andes, Ethiopian highlands, Himalayas, Papua New Guinea. Vegetation: Boreal (NF)- around souther part, trees are bigger, northern trees have stunted growth Montane (MF)- warmer lower elevantion areas, trees are stunted at higher elevation. Life zone concept: Low altitude and low latitude=more life. High altitude and High altitude= less life. Deciduous needleleaf trees: too cold for normal needleleaf trees-> found in Northern Minnesota, Canada, and Siberia. Animals in the NF/MF: Low species diversity Tundra: treeless environment found north of boreal forests. Very high latitudes Permafrost- permanently frozen layer of soil Vegetation- no trees, short grasses. Animals in the Tundra: Caribou, reindeer, elk, hares, foxes. Adaptations: thick fur, thick layers of fat, fur color. Permafrost and Climate change: permafrost releases lots of organic material when melted, decomposes and releases CO2 and CH4. Positive feedback loop: climate warms-> more greenhouse gasses.
Deserts
Climactic breakdown: characterized by low precipitation not by temperature. Chronic water deficit (POTET deficit). POTET is higher than precipitation. 1/3 of earths surface is a desert. Hot and Cold Deserts: hot deserts in low latitude, cold deserts in mid-latitude. Subtropical high: high pressure air is descending and not condensing, no precipitation. Coastal Deserts: Cold ocean currents keep currents dry, ex. Northern Andes, Mexico, Namibia. some rain shadowing in the Andes, Iquique Chilé- Atacama desert, impact of coast- double rainshadow as well as subtropical high. Interior deserts: Gobi desert in Mongolia, Sahara, central asia, Western US, far from oceans, oceans are a source of moisture. Diurnal Temperature Range: 100 degree swings in one day have been reported, hot in the day, cold at night. Generally pretty windy, little vegetation to disrupt wind, which drives sand dune development. Precipitation is unpredictable and rare, but when it does, it feeds ephemeral streams. Withering Streams: Streams get narrower as you get closer to the mouth of the streams, which is opposite of most other streams. Ex. Loa river in Chile, Colorado River. Nile starts in africa where it rains a lot, and the mouth at the end evaporates that water due to hot climate, so the mouth is dry. Desert Soils: Often aridsols and entisols very little organic material and moisture. ephimeral annuals: short lived plants that produce a lot of seeds that germinate the next time that there is rain. Taproots and Phreatophytes: taproot is a large, central, and dominant root which other roots sprout laterally. Phreatophyte is an adaptation- root gets groundwater and can grow up to 400 feet deep. Allelthopy: a biological phenomenon by which an organism produces one or more biochemicals that influence the germination growth, survival, and reproduction of other organisms. Ex. American crestobush. Succulence: plants that have some parts that are more than normally thickened to retain water in arid climates and thorns to protect itself. Stomata: pores in leaves that facilitate gas exchange for photosynthesis. Others don't have leaves at all and rely on photosynthesis in their stems. Fuzzy Leaves: Wicks little bit of water from the air, leaves that curl up during the day and fold back at night. Xerocoles: animals adapt to the desert. Adaptations include speed, camo, special metabolic features to get more water from food, crystalline urine, large ears, light color for albedo, burrowing underground. Fennec Fox is an example. Aeolian Geomorphology: The hallmark of geomorphology in arid environments. Ex. sand dunes Sand dunes are large accumulations of sand shaped by 3 main factors: sand supply, availability, wind direction and speed. Types of Dunes: Seif- longitudinal dunes elongated and indicative of contrasting wind directions. Barchan dunes- found in areas where wind blows in one direction- looks like a crescent shape. Star dunes- indicative of multiple wind directions, and blowout- sand in vegetation, vegetation goes away and sand blows out. Parabolic- U shaped dune with vegetation around the perimeter. Aeolian processes: tells us about past wind speeds and direction of winds.
Temperate Rainforests
Climate Breakdown: no harsh seasonal extremes- mild summer Vegetation: very high biomes- lot of big trees. Not a lot of species diversity. Slow growth, ancient trees- tallest and oldest trees, makes trees vulnerable to logging, can't recover from clear cutting because trees are so slow. Examples: Western North America, Southwestern South America, and New Zealand
Equatorial and Tropical Rainforest (ETR)
Climate: High temperature all year, high precipitation all year Why: ITCZ, always strong insolation, low pressure and heavy precipitation is never too far away due to low pressure systems Where: Amazon basin (Peru, Brazil, South Venezuela) Animals and adaptations: highest biodiversity in the world, biopiracy (exploiting plant and animal species by claiming patents to restrict their general use for indigenous people). Symbiotic interactions. Symbiosis: interaction between two different organisms living in close physical association. Types- mutualism (both organisms benefit) ex. clown fish and anenomy. Commensalism: one organism benefits, the other is unaffected. Parasitism: one organism benefits, the other is harmed Classic vegetation characteristics: trees are evergreens. Epiphytes: these types of plants use other plants for physical support and get nutrients from debris. Lianas: vines, stranglers, epiphytes that drop roots to the ground and kill host plant. Layering: Emergent crowns, canopy, understory (extremely dense, only 1% of sunlight passes through), floor (very dark, species survive in the shade Soils: nutrient pore- oxisols and utisols. Slash and burn agriculture: burn a track of rainforest down to temporarily improve fertility. Issue facing the biome: deforestation in the ETR. Much has already been lost: roughly half ahas been deforested. Causes: agriculture, timber, ranching and grazing of sheep and cattle, fueling wood, mining. Loss of biodiversity, massive carbon emissions.
Mid-Latitude Broadleaf and Mixed Evergreen
Climate: Humid Continental- warm summer, cool to cold winter. Precipitation all year but maximum is during summer. Deciduous species: species lose their leaves in the winter in response to stress. Evergreen: trees that don't lose their leaves. Gymnosperm: more primitive- seeds encased in cones. called conifers (cone bearing tree)- Pine trees are an example Animals: Deer, Squirrels, bears, foxes, songbirds, turkeys, etc.
Mediterranean Shrubland
Climate: called by many the most favorable environment for people. Warm to hot summer, cold winters. Dry summers, wet winters, opposite of all other climate types Distribution: only 5 places on earth, Southern and central california, central chile, SW of southern Africa, Sw Australia. Also associated with western sides of continents. Chaparral: Characteristic of vegetation of MSh environments. thorns, evergreen trees, funnel morphology, sclerophyllous trees leaves, deep roots, depednence on fire. High rates of endemism (species only found in one place). Fruiticulture/Viticulture/Viniculture: huge sources of fruits and vegetables. Importance of Chile- produces lots of produce for the US. Viticulture- growing grapes. Viniculture- growing grapes for wine. Wildfires in California: Climate is large driver- long dry season, Santa Ana winds. Increased fuel load- largely anthropogenically driven. Once fire starts it spreads fast and is hard to put out.
Tropical Seasonal Forest and Scrub and Invasives
Climate: similar to ETR, usually slightly higher latitudes than the ETR. Hot all year, but has high seasonal variation in precipitation. 8 months wet, 4 months dry due to ITCZ. Areas with fewer than 40 rainy days during the four driest consecutive months. Where: Venezuela, Brazil, pacific coast of Central America, South/Central Africa, part of Madagascar, North India, mainland Southeast Asia. Vegetation Characteristics: no distinct layering, but quite thick with some openings. During dry months, many trees adapt by shedding their leaves, called deciduous trees.
Mid-latitude Grasslands (MGr)
Grassland: Grassland is an area in which the vegetation is dominated by a nearly continuous cover of grasses. Mid-latitude grasslands are temperate grasslands while savannas are tropical, low-latitude grasslands. Climate: War to Hot summers and cold winters- displays seasonal extremes. Most grasslands are in continental locations away from large bodies of water. No distinct dry season- varies throughout the year. Examples: Midwest Grasses: Family- Poacene. Monocotyledons: seed has only one embryonic leaf. Dicotyledons: two embryonic leaves. Long leafy stems. C3 grasses are cool season grasses, C4 are warm season grasses. Trees in the MGr: there are not many trees in grasslands because fires start frequently, and kills trees when they're babies. Grasses grow back faster. Animals: Burrowing-> gophers, prairie dogs, field mine. Burrows provide shelter from summer heat, fire, and predation. Human Modification: of all terrestrial biomes, the MG biome has seen the most human modification. Historical contexts of exploitation: Food production. Very fertile soil- mollisols, lots of humus, good soil blend, loess. Technological innovation, steel plows, railroad, wells and windmills. Homestead act and barbed wire, 160 acres "the closing of the frontier"
Biome
a large naturally occurring community of flora and fauna occupying a major habitat, e.g., forest or tundra.
Life Zone Concept
altitudinal changes in environment and vegetational belts corresponds with latitudinal changes
Invasive species
any kind of living organism that is not native to an ecosystem and causes harm. Ex. emerald ash bore, paraffin bush and crocodiles.
Adret slope
face oriented towards the sun, less lush vegetation because of more evaporation
Soil
local influence- sandy soil-> poor at holding water Loamy soil- good at holding water
riparian zones
local influence- vegetation zone that relies on waters from adjacent rivers and lakes
Scalar Organization of Ecology
organisms population community ecosystem biome biosphere
Ecology
relations of organisms to one another and to their physical surroundings
Ubac
shady, mountain face not oriented towards the sun, lusher vegetation, less intense insolation, less evaporation-more vegetation
Biosphere
the sphere that concerns living things
ecotone
transition zone between biomes, has characteristics of both