physical geography exam 2
Mesothermal (C) climates
- 1 month below average temp 18oC (64.4oF) - 1 month below 10oC (50oF) - Csa / Csb (Mediterranean Climate) - Dry summer - Along west coasts between 30o and 40o latitude - Cfa (humid subtropical) - Wet year round - Southeast U.S. (including where we live!) - Cfb and Cfc (marine west coast) - Wet year round - Summer's cooler than Cfa - Along west coasts often extending poleward of 40o latitude
oxygen isotope analysis
- A means of reconstructing paleoclimates (a widely accepted method) - The oxygen isotope ratio (18O/16O) indicate changes in ocean temperatures relating to glacial cycles - Air bubbles give atmospheric gas content - Sulphuric acid content of the ice indicates periods of volcanic activity
Steppe (BSk and BSh)
- Annual precip of 25-50 cm/yr (10-20 inches/year) Greater than deserts - The middle of continents and in the lee of high mountains. - Factors that may cause steppe climate: Strong Subtropical High pressure Rain-shadow Continentality
BWh and BWk Desert
- Annual precip. fewer than (10 in./year) Precip. irregular and unreliable - Factors that may cause an area to be a desert: Strong Subtropical High pressure Rain-shadow Continentality
Driest Place on Earth
- Average annual rainfall 0.04" per year - Many records indicate that no rain fell in portions of the desert from 1570 to 1971
food chain vs. food web
- BOTH food chains & food webs show the linkages in an ecosystem Essentially who eats what (or who) - Food chains: linear connections between trophic levels - Food webs: the overlap between multiple chains
Climate: Scale
- Climate can be measured at different scales macro: a large region meso: a medium- sized region micro: small
Tundra
- Coldest of all the biomes - Low biotic diversity - Simple vegetation structure - Limitation of drainage - Short season of growth and reproduction - Animals: pikas, marmots, mountain goats, sheep, elk, arctic foxes, caribou, arctic hares, wolves, and polar bears
desert biome
- Cover about one fifth of our planet - Lack of precipitation - Evaporation exceeds precipitation Plants: - Xerophytes - Probe deeply for water - Lie dormant for long periods - Drought resistant - Are few and far between in very dry locations (e.g. Atacama desert) Animals of the desert are primarily nocturnal - Longer tails, ears, noses, and legs to circulate blood, which helps cool the animal down
simplified Koppen system
- Divided into six major climate zones A = Humid Tropical (no winter season) B = arid and semiarid C = humid mesothermal (mild winter) D = humid microthermal (severe winter) E = polar (no summer season) H = Highland
soil orders
- Entisols - Inceptisols -Histosols - Andisols -Gelisols - Aridisols - Vertisols - Mollisols - Alfisols - Spodosols -Ultisols -Oxisols
energy flow
- First Law of Thermodynamics: Energy cannot be created or destroyed. - Conversion/storage of sunlight: Organic material in plants/animals Flows along food chains - The energy in a system is stored in the biomass The total amt. of all living material in an ecosystem.
sub-arctic (Dfc, Dfd, Dwc, Dwd)
- Found only in N. hem - Most extreme of the microthermal climates - Ocean Currents East Coast: subarctic is further south West: subarctic is further north - PolewardLimit of Forests Taiga(boreal forest) - Permafrost Permanently frozen layer of soil Varies in thickness Repeated cycles of expansion and contraction - Very short growing season (50-75 days) - Subarctic covers vast areas of Eurasia and North America
humid micro thermal
- Humid continental, hot summer (Dfa, Dwa) - Humid continental, mild summer (Dfb, Dwb) - Subarctic with a cool summer (Dfc, Dfd, Dwc, Dwd) - Similarities: Do not exist in S. Hemisphere Four distinct seasons "Recognizable" summer Distinct winter "Preparatory" seasons of Fall and Spring - All of these experience surplus of precip over potential ET - In general, year round precip. (except area in Asia) - High frequency of mT in summer and cP in winter - Dominance of continentality - Cyclonic storms and polar jet
Warm/ hot summers Dfa, Dwa
- Largest extents North America - Much smaller in Europe and Asia - High agriculture potential Longer growing season Depends on Latitude - Dfa - No dry season - Dwa - Dry winters
Mild summers Dfb, Dwb
- Lies adjacent to and poleward of Dfa and Dwa - Severe winters - Highly variable weather - Shorter growing season - Less precipitation, more snowfal
Marine west coast (Cfb and Cfc)
- Location: 40o and 65o latitude. - Oceanic moderating effect - Cloudy, rainy, stormy, foggy - Continuous influence of westerlies - Relatively mild Winter - Ample precipitation Mild-summer (Cfb) Cool-summer (cfc) - Fjords: a long, narrow inlet with steep sides or cliffs, created in a valley carved by glacial activity.
Mediterranean (Csa, Csb)
- Location: West coasts (generally) 30o- 40o latitude - Dry summers, wet winters - Europe's hottest climate - Alternation of subtropical High in summer (dry) and westerlies in winter (wet) - Csb has lower summer temp. (strong maritime) - Csa has hot summers(continentality)
humid subtropical climate (Cfa)
- Location: east coasts 15o and 20o to 40o latitude - Warm, moist air circulates from the south around subtropical High in summer (wet and hot) - Westerlies in winter (wet and cool) - Wetter than Mediterranean even though similar latitude. - Productive Climate - Long growing season
Koppen system
- Most widely used - Based on regional temperature and precipitation Uses vegetation boundaries to create different categories - Advantages: Easy to measure Measured most often - Disadvantages: Only average monthly temp and precip. Ignores winds, clouds, intensity of precip.
Polar (E) Climates
- No month has an average temp greater than 10oC (50oF) - EF (ice sheet) no month > 0oC (32oF) - ET (tundra) at least 1 month averages > 0oC (32oF)
soil water
- Original source is precipitation - Affected by the particle sizes smaller particle sizes hold less water Capillary water: - Within pore spaces, a stored supply available to plants Hygroscopic water: - Thin film attached to particles, not available to plants Gravitational water: - Water that percolates through a soil under the force of gravity
internal variations of Dfa, Dwa
- Precipitation decrease away from sea water.
factors affecting soil formation
- Soil = f (Cl,O,R,P,T) - the so-called CLORPT factors of soil formation Soil development is a function of: - Climate (Cl) - Organic matter (O) - Relief (R) - Parent material (P) - Time (T)
Microthermal (D) climates
- Usually year round precip. - Shorter summers and colder winters than "C" - Found only in N. hem. - Dfa and Dwa Humid continental, hot summer - Dfb and Dwb Humid continental, mild summer - Dfc, Dfd, Dwc, and Dwd Subarctic
Aw tropical savanna
- Warm year round - Distinct seasonal precipitation pattern - Less precip. and shorter wet season as compared to monsoon - rolling grassland scattered with shrubs and isolated trees (a tropical grassland) - under the influence of the ITCZ (doldrums) for part of the year, rain- suppressing tropical highs for the other part - rainfall less predictable - large variation in annual precipitation
Arid (B) Climates
- Year round moisture deficiency - Precip received < potential ET - 15o to 30o latitude, and rain shadows - BW (desert) annual precip. is less than half of annual potential ET - BS (steppe) annual precip. is less than potential ET, but more than half
middle- lat grasslands
- Zone of transition between mid-latitude deserts and forests. - Tall-Grass Prairie (wetter; E of 100th meridian) - Short-Grass Prairie (W of 100th meridian)
Habitat
- a location where an organism lives and performs its specific role in the system - ecological niche: combination of role and habitat - generalist= can eat a variety of things - specialist= koalas only eat eucalyptus
forest biomes
- annual moistures balance is positive - tropics (ITCZ and/or monsoon) - middle latitudes with high frequency or cyclonic storms
biogeography
- biogeographers study the distribution of the world's many species and how the distributions change over time - strong ties to biology, ecology evolution studies, climatology, and soil science
highland climates
- climate mosaic - Tree line: the line beyond which low winter temperature and severe wind stress eliminate all forms of vegetation except those that grow low to the ground - snow line: the line above which summer melting is insufficient to remove all snow - Temperature decreases with increasing altitude - Controls of Highland Climates: Elevation Exposure Coastal or interior location High or low latitude Slope Aspect
factors affecting soil formation
- climate, temp and organic matter Climate - Moisture Conditions Ample precipitation supports plant growth which increases organic content Too much precipitation will cause leaching - Evaporation rate
ice sheets
- coldest place on earth in antarctica (min isolation, high albedo, and high elevation)
ecosystems
- communities of organism that function together in an interdependent relationships with the environment in which they live - ecosystems are OPEN SYSTEM
Measuring past climate
- confidence in the measuring decrease with age - several methods can correlate to give a better picture of past climate
organic matter
- decomposed and un-decomposed plant and animal material - improves soil structure and nutrient - restores minerals to soil - 5% of soil
soil horizons
- distinct layers distinguished by their physical and chemical properties - designated by set of letters that refer to> composition dominant process position in the soil profile
tropical monsoon (Am)
- distinction between rainforest and monsoon - ITCZ shifts>> when it shifts away it is dry
Climate: Classification
- early greeks (aristotle): torrid, temperate, and frigid - two weather variables most often used today: temperature (minimum of 30 years of data) precipitation (minimum of 30 years of data - classify climate atmosphere elements (statistics and math) = empirical based on the cause (genesis) = genetic
secondary productivity within Ecosystems
- ecological efficiency: the efficiency with which energy is transferred from one trophic level to the next - advantages of a vegetarian diet as we experience rapid population growth
calcification
- evapotranspiration exceeds precipitation - often thick calcium carbonate - deserts of american west
Climographs
- graphs showing both temperature and precipitation of a place precipitation: bar graph temperature: line graph
podzolization
- high middle latitudes - moist with short, cool summers and severe winters - acidic soils, gray- ish in color - east coast of US
Tropical (A) Climates
- high temp year round - near equator - no winter season ( avg. temp of coldest month above 18C or 64.4F) - ITCZ -Af (tropical rainforest) - Aw (dry winter tropical savanna) - Am (along coast with tropical monsoon)
latertization
- humid and subtropical climates - result of high temp and abundant precip - latrite: soil type (brick like) - no O horizon, absence of organic acids - topsoil reddish
vostok
- ice core data shows correlation between CO2 and temp
measuring past climates
- ice cores 800,000 year record - dendrochronology tree ring analysis= 1,000 yr record - pollen analysis (palynology) thousands of years - ocean sediments 200 million year record
organizations within ecosystems
- major component abiotic: physical environment that plans and animals live in autotrophs heterotrophs herbivores carnivores decomposers (detritivores) - trophic structure, food, chain, foods web
temperate evergreen forest
- marine west coast - large sized spruce and fir, redwoods (N.America) - evergreen needle leaf forest - similar appearance to the tropical rainforest with rainforest multilevel structure
Humid mesothermal climates (C)
- moderate temperatures (meso-) - seasonality (distict summers and winters)
Highland (H) Climates
- mountain barrier can increase and decrease precipitation, cloud cover, and temperature
succession
- natural vegetation - plant community - succession> natural vegetation develops in a squence of stages - primary - secondary
animals of the tundra
- need fat reserves - hibernate (some of them do)
air
- occupies same pore space as water more water= less air in soil - some air is critical (fire ants, worms) 25% of soil, but variable
Causes of past climate change
- ocean chnages shifts, weakening of currents - landmass chnages continent drift
development of soil horizons
- parent material - soil profiles show color structure composition other characteristics with depth
polar climate regions
- polar climates (furthest from equator) no month averages above 10C(50F) no summer no trees large annual net loss of radiation two climate types ET(tundra) EF(ice sheet) most severe and restrictive climate on earth
Subarctic (Dfc, Dfd, Dwc, Dwd)
- short cool summers and long harsh winters - at least one month with an average temperature above 10C (50F) - farthest poleward of microthermal climates
acidity and alkalinity
- soils in the east tend to be acidic - soils in the west tend to be alkaline
taiga/ boreal forest
- taiga: russian word for "forest" - largest biome in the world the biome of the coniferous (needle-leaf) forest 29%of the world's forest cover - largest areas in russia and canada - many animal hibernate in winter bears, moose, reindeer, caribou, elk, beaver, wolverine
biomes
- terrestrial ecosystem defined by temp and precipitation - a vegetation unit characterized by similar flora (plants) and fauna (animals) - largely follows climates (remember Koopen climates originally divided by vegetation growing limits)
major periods in "recent" climates
- the last 100,000 years cold, glaciations - wisconsin Glaciation 18000 years ago continental ice sheets Little Ice Age - 1600 to 1850 C.E. - Coolest period since the end of the last glaciation - Natural climate variation - Increased volcanic activity Tambora (Indonesia), 1815
environmental controls
- tolerance: ecological optimum refers to the environmental conditions in which a species will flourish - Ecological Optimum - ecotone: overlap or zone of transition between two plant or animal communities - biomes: terrestrial ecosystems defined by temp and precip.
tropical forest
- tropical rainforest Competition between species Lianas Almost a closed system Galleria forest Arboreal animals - monsoon rainforest dry vs. wet season - thornbush and scrub
Am tropical monsson
- warm all year - seasonally heavy rainfall - monsoon: a seasonal reversing winds (from land to sea) accompanied by corresponding changes in precipitation
Arctic and alpine tundra
-Very short growing season - Dominated by subfreezing temp. and thin snow cover - Top 36-60 cm of ground thaws during short summer period Tundra: mixture of grasses, herbs, sedges, mosses, lichens, and small shrubs - Bush tundra - Grass tundra - Desert tundra
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Arid regions: the "B" climates
Arid climates: - Wind direction and ocean currents can accentuate aridity in coastal regions. Leeward vs. Windward Cold ocean currents and temperature inversions - Deserts: Amount of precip. < half PET - Steppe: Precip. more than half but < total PET
factors affecting soil formation cont.
Climate - Global vs. Local scale - Equatorial: Higher temps increase soil microorganisms, preclude thick accumulations of humus - Middle Latitudes: Cooler temps slow decay and produce rich humus - Polar Latitudes Cold temperatures and limited plant growth result in thin humus
examples of plant adaptations to limiting factors
Heliophytes - plants that grow best in full sunlight Sciophytes - plants that grow best in shade. Xerophytes - plants that grow best, or tolerate most successfully, dry environments Mesophytes - plants that require moderate moisture conditions Hydrophytes - plants found growing in water or very wet soils Halophytes - plants adapted to high saline levels
CLORPT factors-relief
Land Surface Configuration Relief Slope Aspect (direction its faces)
middle latitude climates
Microthermal and Mesothermal: - A lot of change and most of the world's population - Changing seasons associated with: Migrating air masses Cyclonic activity along polar front. - Micro-thermal - poleward Shorter summers/longer winters - Meso-thermal Longer summers/shorter winters
soil classification cont.
NRCS Soil Classification System - Based on development and composition - Hierarchy • Order (12 Orders) • Suborder • Great Group • Subgroup • Family • Series (10,000+ series)
CLORPT factors- organic matter
Organic Material - Plants and animals die and decompose - Leaves fall to the ground - Most fertile soils are typically grasslands - Soils are ALIVE! Microorganisms (e.g. bacteria) • Earthworms, ants, termites,...
Past Climates
Paleoclimatology- study of past climates
CLORPT factors- parent material
Parent Material - Residual parent material (e.g. physical or chemical breakdown) - Transported parent material (e.g. carried by water, wind, glacial ice, etc.) - Chemicals & nutrients reflect composition
Arid Climates
Precipitation Effectiveness: - Criteria for determination of desert, steppe, or humid. - Effective Precipitation: amt. of precip. available for use by plants and animals. Related to temperature Compared to areas w/ lower temps., warmer areas require more precip to have a comparable effect on soils and plants.
productivity within ecosystem
Primary Productivity- conversion of solar energy to plant matter through photosynthesis. - Affected by several factors: • Photosynthesis • Latitude • Soil moisture • Temperature • Nutrients • Age • Atmospheric composition
soil- forming regimes cont.
Regimes of Local Importance - Salinization: concentration of salts Occurs most often: - in dry areas - Intensive irrigation - Gleization: poorly drained soils in cold, wet climates "Gley" soils Peat bogs
development of soil horizons cont.
Soil Horizons: - O horizon> organic - A horizon> topsoil - E horizon> Eluvial - B horizon> deposition - C horizon> Weather parent material - R horizon> Parent rock paleosols - ancients soils - buried by younger soils
soil classification
Soil Taxonomy - Soil classification system that is based on their characteristics - Natural Resources Conservation Service (NRCS) - Mapped by their spatial distribution Soil Surveys - Books that outline and describe soils in a region - Useful for factors such as fertility, irrigation, & drainage
classifying climates
Thornthwaite System - Classifying based on moisture - Used often by soil and water resource scientists, agriculturalists - Potential evapotranspiration
arid climate regions
Two major concentrations: - Tropics of Cancer and Capricorn and 10o - 15o degrees poleward and equator ward. Related to subtropical high pressure systems. Mojave Desert Sahara Desert Baja California Namib Desert Atacama Desert Australian Desert - Continental Interiors of the Northern Hemisphere Gobi Desert
inorganic material
elements of earth's crust, come from broken up soils - 45% of soil - clay, silt and sand
Tundra ET
extremely short, cool "summer"
major soil components
four major components of soil - inorganic materials>> soluble and insoluble - water - air - organic matter - interaction and proportion of each are important factors
classification of terrestrial ecosystems
four types - forest - grassland - desert - tundra
examples of adaptation
low light - large leaf area to maximize sunlight reception for phtosynthesis - stratification> layers adapted to differing light levels and wavelengths intense insolation - waxy coating on leaves, to prevent "sunburn". - smaller leaves large- surfaced tropical leaves which also often have central furrow and "drip- tip"
plant adaptations
low wind - large colorful flowers - large succulent and juicy fruits high wind - grasses (flexible stems) - small seeds - aerodynamic seeds - much pollen cold and wind - deciduousness - needleleaf growth form - low- growth forms
middle- latitude forest
mediterranean woodland - 30- 40N and S latitude - Mediterranean climate - north vs south facing slope - drought resistant plants - grapes and olives are common crops
soil acidity and alkalinity
pH scale (0-14) lower Ph= high acidity - soil acidity and alkalinity helps determine available nutrients
marine ecosystem
pelagic life: - comprised of all organisms that float, drift, or swim in the open ocean plankton: - phytoplankton>> base of the food chain - zooplankton • Nekton • Benthos • Life in ocean depends on: - Sun's energy - Available nutrients • Most organisms near surface
secondary succession
reduce an already established ecosystem - there is pre-existing soil and a seed bed
soil- forming regimes
soil- forming regimes - vary mainly due to climate and vegetation climate differnces produce 3 primary soil- forming regimes - laterization - podzolization - calcification
soil structure
structure - soil peds - porosity - permeability - classified by form columns prisms angular blocks nutlike spheroids laminated plates
soil texture
texture and proportion of particle size - soil texture - loams - soils with a higher proportion of large particle tend to be well aerated and allow for infiltration
succession and climax communities
the climax community: - final step in process of succession is called climax community - mosaic - matrix - patches - corridors
the dirt on soil
• Soil: a dynamic natural body capable of supporting a vegetative cover • Contains chemical solutions, gases, organic refuse, flora, and fauna - soil integrates>> atmosphere, hydrosphere, lithosphere and biosphere
present climate
anthropogenic releae of CO2is having an impact on global temperature
primary succession
bare substrate (no soil, no seeds, nothing)
symbiotic relationships
bees and flowers mutualism
animal adaptation
bergmann's rule: with in warm blooded species, the body size of the subspecies usually increases with the decreasing mean temperature allen's rule: in warm- blooded species, the relative size of exposed portions of the body decreases with the decrease of mean temperature an example would be how the African elephant cools its self with its ears he desert fox and its big ears
middle- latitude forest cont.
broad- leaf deciduous forest - seasoning changes - tress almost as tall as tropical rainforest, although more light reaches ground - mixed forest - coniferous forest southern alaska to central california
characteristics of soil
color texture structure acidity alkalinity capable to hold and transmit water
plant adaptation
wetness - buttress roots - drip tips on leaves dryness - reduces leaf area - no leaves - needles and/ or "hairlines"
Af tropical rain forest
_ warm all year - consistently high rainfall throughout the year
CLORPT factors- time
time - young and mature soils - alluvium - loess - glacial deposits
grassland biomes
tropical savanna - scattering trees - tall grasses - drought resistant - red colored soils - water tables fluctuates - large migratory herds
limited factors that influence an ecosystem
two types of limiting factors recognized: - physical>> temperature and/or moisture regimes, light requirements, soil, topography, natural hazards - biotic>> competition, predation, and presence or absence of a food supply - in response to limiting factors, plants and animals have adapted
Humid "A" climates
warm and rainy central america, top part of south america, mid- africa, indonesia pretty much anything along the equator this area is great for growing coffee