Ecology Final - 24, 25, 27 & 29
....several species in a population....
*false - only one species in a population
Three types of Coral Reefs
-Fringing reefs grow seaward from the rocky shores of islands and continents -grows around volcanic islands -Barrier reefs parallel shorelines of continents and islands and are separate from land by shallow lagoons -around the continents -Atolls are rings of coral reefs and islands surrounding a lagoon, formed when a volcanic mountain subsides beneath the surface -ring of coral and all the other mountains that were there have sunken, blown up, etc.
Three forces interact to form the conditions unique to the Artic Tundra
-Permanently frozen deep layer of permafrost -overlaying active organic matter and mineral soil that thaws each summer and freezes the following winter -vegetation that reduces warming and restarts thawing in the summer -three main layers of soil: active layer, permafrost, talk -active layer is frozen for 8 months of the year and thaws in the summer - giving rough topography
Variables Affected by Flow RAte
-oxygen content - as water is running fast, it adds oxygen back into the system -rate of nutrients spiraling -physical structure of the stream banks and bottom - meandering -organisms living in the stream - base flow on top, adapted to heavy flow or hide etc.
Native Grasslands of North America
-tallgrass prairie is dominated by big blue stem growing 1 m tall --Mississippi --blue stem grass is extremely tall -mixed grass prairie composed of needlegrassgrama grass (great plains) -shortgrass prairie dominated by sod-forming bluegrama and buffalo grass --move west --desert grassland replaces buffalo grass with three-awn grass -annual grassland is characterized by rainy winters and hot, dry summers (mediterranean climate) --central valley of california --mediterranean climates grow in the winter
Flowing-Water Ecosystems Vary in structure and types of habitats
-turbulent riffle - fast moving shallow areas with heterogeneous substrate (particles of different sizes) --white water, boils (bottom is cobbly -quiet pool - slow moving, deeper areas with homogeneous substrate of sand and/or silt -sediment settles (homogeneouse muddy or sandy bottom)
Chapter 24 Terrestrial Ecosystems
1. Biogeographical Realms 2. Terrestrial Biomes 3. General Characters of Plant Life 4. Tropical Forests 5. Temperate Forests 6. Northern Coniferous Forests 7. Tropical Savanna's 8. Temperate Grasslands 9. Deserts 10. Chaparral 11. Tundra
Tropical Rainforest in Five Vertical Layers
1. Emergent Canopy - trees widely spaced, tallest trees, sticking way above the canopy line 2. Upper Canopy - Medium spaced crowns, smaller trees, but can still capture enough light 3. Lower Canopy - trees 4. Understory - Shrubs and saplings 5. Ground Cover - herbs and ferns
Chapter 25: Aquatic Systems
1. Intro a. marine b. fresh water c. estuarine 2. hydrological cycle 3. stream networks 4. what is a watershed a. longitudinal profile 5. downstream changes a. meanders 6. stream habitats 7. current velocity vs. discharg (flow) 8. storm hydrograph 9. Adaptations to living in current 10. functional feeding groups 11. stream continuum 12. estuaries 13. oceans a. ocean strata b. pelagic communities c. benthic communities d. coral reefs
Chapter 27 Global Scale Patterns of Biodiversity
1. Introduction 2. Number of Described Species 3. new species described each year 4. species Richness over geologic time 5. mass extinctions over geologic time 6. examples of latitudinal patterns of diversity a. marine bivalves b. mammals c. ants and breeding birds d. trees 7. Richness vs. AET 8. AET and Productivity 9. Bird and Mammal Richness and PET 10. US Biodiversity Hot Spots 12. Marine Richness and Productivity
Tropical Savannas are characteristic of Semiarid Regions with Seasonal Rainfall
A savanna includes range of vegetation types in the drier tropics and subtropics characterized by a ground cover of grasses with scattered trees or shrubs. Distinct seasonality in precipitation and large inter-annual variation in total precipitation Support large herds of herbivores and their predators Less rain, much drier, less abundance of trees Large herds of herbivores, and their predators The further you distance yourself from the rainforest the more dry it becomes
The alternate freezing and thawing of the upper layer of soil pushes stones and other material upward and outward from the material upward and outward from the mass to form a patterned surface
Active layer is frozen for 8 months of the year and thaws in the summer - giving rough topography -Thawing and freezing causes rough topography
Simple Hydrologic Cycle
All systems tied to this cycle -evaporation from the ocean
Stream Meanders - why do streams meander?
As streams cut through valleys they start to meander (weave/zig-zag back and forth) -the cutting power of the water, and the resistance of the sediment dictate the meander -stream doesn't go straight A meandering reach showing the line of maximum velocity and the separation of flow that produces areas of deposition and erosion. Cross-sections show the lateral movement of water at the bends. Sand bars are built by this - meander scares - water spirals
Other Deciduous forests
Asiatic broadleaf forest (eastern China, Japan, Taiwan, and Korea) Southern Deciduous forests (Andes, Chile, Tasmania, and New Zealand)
Longitudinal changes in streams
At the source, a stream may be small, straight, and swift, with waterfalls and rapids As the gradient becomes less steep, velocity decreases and the stream begins to meander and deposit its load of sediment Where a stream flows into a lake or sea, the velocity of water is essentially stopped and the water is forced to drop its sediment load, forming a delta Size - width and depth change, gradient changes (how deep) -when they get to the end of their lives they drop their sediment and turn into delta
Oceans Exhibit Zonation and Stratification
Benthic Zone - bottom region Pelagic Zone - whole body of water -horizontal zone --neritic province - water that overlies the continental shelf --oceanic province - water that overlies the abyssal plane -verical zones --epipelagic or photic zone - surface to 200 m, experiences sharp gradients in illumination, temperature, and salinity --Mesopelagic zone - 200 to 1000 m, little light penetrates and a more even temperature gradient Ocean - neritic zone - shallow goes to continental shelf, horizontal zone Oceanic - out in the ocean, horizontal Epipelagic - vertical surface to 200m Mesopelagic - 200 to 1000m vertical Vertical zones -epipelagic/photic zone: surface to 200m, experiences sharp gradients in illumination, temeprature and salinity -mesopelagic zone - 200 to 1000m little light penetrates an a more even temperature gradient -Bathypelagic zone - where darkness is virtually complete, high pressure, cold -Abyssopelagic zone - extends from 4000m to the sea floor -Hadalpelagic zone - includes areas found in deep-sea trenches and canyons
Benthos is a world o f its own
Benthic communities support a high diversity of species -shallow benthic regions: 250 species of polychaete worm and over 100 species of pericarid crustaceans -deep-sea benthos: 707 species of polychaete worm and 426 species of pericaridian crustaceans Benthich bacteria synthesize protein from dissolved nutrients and become a source of protein, fat, and oils for other organisms -benthos worms - fangs to secrete toxins -tube worm - burrow into the sand -sand worms Pericardial crustaceans: aphropods, beach hoppers, madashrimp, shallow or deep water High temperature, deep-sea hydrothermal vents occur along volcanic ridges in the ocean floor Vents form when cold seawater flows down through cracks in the basaltic lava floor and the waters react with the hot basalt - water becomes enriched with minerals (eg. copper, iron, sulfur, zinc) -white smokers - rich in zinc sulfides -black smokers - rich in copper sulfides Primary producers are chemosynthetic bacteria that oxidize sulfur compounds (H2S) to release energy Primary consumers include giant clams, mussels, and polychaete worms that filter or graze on bacteria Very deep water -hydrothermal vents from the floors let hot water come out of the center of the earth and release chemicals/minerals (sulfur and zinc) sulufur comes out of black smoke, zinc comes out of white smokers (also copper) -chemosynthetic (take materials not from the sun) -in the dark where no sun is able to penetrate Vents out of corals and sands - fish typically blind
Biomes
Biotic Units and are classified by predominant plant types -Developed by EE Clements and VE Shelford 8 Major terrestrial biomes -Tropical forest -Temperate forest -Coniferous forest (taiga or boreal forest) -Temperate grasslands -Tropical Savanna -Desert -Chaparral (shrub lands) -Tundra *plant types define biotic units
Evergreen leaves live beyond a year
Broadleaf evergreen leaves have no distinct growing season, growth continues year-round Tropical plants, Rhododendron Neadle-leaf evergreen leaves may have short growing season (northern climes) or grow year-around (spruce, fire, pines)
Plant types: early vascular plants (Psilopsids), Pteridophytes; Gymnosperms; Angiosperms
Changes in the plant worlds -extinction due to the cold Pteridophytes - ferns Gymnosperms - pine cone Angiosperms- flowers
Stream Continuum
Changes we expect to see downstream to lower mississippi/ocean Moving down, more broad fish that live on the bottom of the water CPOM at the top of the water, FPOM further to the bottom Algae provides food for the grazers at the middle part of the stream Water gets deeper and darker, less light is available, some plankton available depending on how clear the water is Decomposes at different rates
Forest Ecosystems
Characterized by a closed canopy of trees
Grassland Ecosystems
Characterized by grasses and herbaceous plants - no trees
Tundra Ecosystems
Characterized by low growing shrubs in cold, dry climates
Desert Ecosystems
Characterized by specialized plants that can withstand arid conditions *highly adapted things that can live in such severe weather conditions
Distribution of terrestrial biomes by precipitation and temperature regimes
Clements -bottome line - mean annual temperature (warmer to the left, colder to the right) -vertical line - mean annual precipitation *If your mean temperature is 25 and your mean precipitation is 400 you are in a tropical rain forest
Conifer Forests Dominate the Cool Temperate and Boreal Zones
Conifer forests exist in abroad circumpolar belt across the Northern Hemisphere and on mountain ranges. Low temperatures limit the growing season to a few months each year. -summers are short, cool, and moist -winters are long, harsh and dry -dominated by needle-leaf evergreen trees -usually found in cool temperate zone -do not grow very fast -far north trees tend to be smaller (growing seasons are short)
Coral Reefs are complex ecosystems built by colonies of coral animals
Coral reefs are unique accumulation of dead skeletal material built up by carbonate-secreting organisms (CaCO3) -living coral -coralline red algae -green calcareous algae -foraminifera -mollusks Reefs attract hundreds of species of algae invertebrates and vertebrates -corals are primative creatures related to jelly fish -calcium carbonate builds up as new coral grows and old coral dies -top layer is living coral -many corals are evolved from filter feeding creatures (from jelly fish) -similar to marine lichin because of algae living within coral -corals live off algea -some corals do filter feeding -algae pick up the nutrients that they need -one of the most endangered areas in the world -acidic material will dissolve them - because ocean is becoming more acidic the coral is being damaged -lots of nutrients going into the waters from rivers, algae from these areas cover these corals and takes over and kills them -good environment for fish to inhabit -very attractive, very stable, and suitable for fish
Drainage Patterns : three main types
Dedritic Radial Rectangular *streams come out of the landscape, different types of drainage patterns
Temperate Deciduous Forests - Where are they now?
Eastern North America Middle Europe Some parts of Asia Chile Eastern Coast of Paraguay New Zealand Southeastern Australia
Temperate Forests
Eastern North America Deciduous Forest -Mixed mesophytic forest (Appalachian plateau) -Beech-maple and Northern Hardwood forests (Northern regions) -Maple basswood forests (Great Lakes States) -Oak Chestnut or central hardwood forests (Appalachian Mountains) -Magnolia-oak forests (Gulf Coast states) -Oak-hickory forests (Ozarks) Asiatic broadleaf forest (eastern China, Japan, Taiwan, and Korea) Southern Deciduous forests (Andes, Chile, Tasmania, and New Zealand) **six different associations - don't have to remember - just know that there are subbiomes that have different types of trees and forests**
Adaptations for living in flowing water
Fast stream animal body form reduces resistance to water current -stream-lined to live in current -flattened to live outside current -some have protective cases -some "stick" to surfaces Most require high, near-saturation DO concentrations Fast stream plant body form -water moss and filamentous algae cling to rocks by strong holdfasts -some algae form sheets that lie flat against the substrate surfaces Fast stream Creatures: Cases made out of rock, fast swimmers, attach to rock by silk/thread, heavy creatures, suck themselves down because of their shape, diatoms Slow Stream Critters: body forms more like lake animals and plants. They tend to hangout in vegetation or burrow into soft sediments More bulky, clams, snails, crayfish, live in vegetation or surface, quiet water
Number of new species described per year
Finding more and more species each year -beetles are still the most dominant in terms of what is being described and what has been described
Mass Extinction over Geologic time
Five major extinctions - we are in a mass extinction if we believe all of this 1. Ordovician 85% loss of marine species 2.Devonian 70-80% marine species extinct 3.Permian 90% all species, maybe 99% extinct (greatest mass extinction on earth) 4.Triassic 20% foraminifera families, 80% quadrupeds, etc 5.Cretaceous 80% all individuals extinct
Major Subdivisions of the North American Boreal Forest
Forest-Tundra Lichen Woodland Closed-crown forest
Forest Tundra Ecotone - Forest Floor
Freeze thaw activity makes the ground spongy
Short grass Prairie
Further west
Deciduous Forests of Western Europe
Germany France
Biome types from in response to a distinctive climatic patterns
Global Climate Trends -mean annual precipitation declines with decreasing mean annual temperature -mean annual temperature declines from the equator to the poles -seasonal variation in temperature increases from equator to the poles -Topography, soil type, and disturbance can also influence biome location *Biomes can be generally characterized by climate -Move away from equator mean annual temperature and precipitation drops -Little seasonal variation at equator, variation increases as you move toward the poles -Topography - what the landscape looks like -Soil type - type of moisture -Direction slope is facing may also have an impact (whether it's facing North or South).
Stream Longitudinal Profile
Head Water = first order stream Moving down stream and lower elevation more gentle stream- moving towards the ocean -mouth = end of stream James River longitudinal Profile - in 600km it drops 1000m
Stream Systems constitute a continuum from head water to the ocean
Headwater forested streams are dependent on terrestrial input of detritus and support shredders and collectors. As stream size increases, the input of organic matter shifts to in-stream primary production, and collectors and grazers are dominant. As the stream grows into a river, a phytoplankton community may develop but most of the energy comes as FPOM from upstream and consumers are mostly bottom-dwelling collectors *leaf processing sequence figure - look up - processing or conditioning sequence for a deciduous tree leaf in a temperate stream -microbes start to mineralize the material (turn into CO2) Identify changes from the headwater all the way to the end - changes in soil, size, organisms, primary production, food (river continuum theory/hypothesis)
Biodiversity: number of described species
How many species there are -more beetles than any other psecies, animal, plant, fungi, etc. (400,000+) -beetles are hardy creatures - hard shells so predation isnt as much as a problem for them -quite a number of species of flowering plants as well -most specious group
Stream Invertebrate Functional Feeding Groups
Invertebrate Feeding Groups -shredders: feed on dead leaves and the bacteria and fungi decaying the leaves they reduce the particle size from CPOM to FPOM -filtering or gathering collectors: feed on fine particulate organic matter (FPOM) -grazers: feed algal and bacterial films coating substrates -gougers: burrow into waterlogged limbs and trunks of fallen trees Predatory invertebrates and fish feed on everybody else Divide into functional feeding groups to process organic material CPOM > 1mm (tree trunks) FPOM < 1mm (bacteria) Most aquatic plants aren't fed on but algae is a main food source
Biogeographical Realms
Large regions roughly equivalent to continents. Biota roughly similar throughout a realm Biota different from realm to realm -Biota are pretty similar throughout a realm
Biodiversity: estimate species richness of invertebrates over geologic time
Layout of geologic time -differences over these periods, growth of species, cenozoic shows the most growth -cambrian - first period you saw life - you see change and see things that look like animals --before this mostly cinobacteria
Broadleaf Evergreen
Leaves that have no distinct growing season, growth continues year-round (tropical plants, Rhododendron)
Needle-leaf evergreen
Leaves that may have short growing seasons (northern climes) or grow year-around (spruce, fir, pines) -pines lose a certain percentage of their leaves during the off season, but still have leaves remaining
Species Diversity
Local diversity: the species diversity of individual communities (forests) Regional (gamma) diversity: the total species diversity across all communities within a geographic area (one specific region) Two main types of diversity - species number
Drought Deciduous Leaves
Lost in response to dry conditions to conserve water (shrubs and trees of the chaparral) *if you lose too much water you can't keep up with cellular growth on the inside
Winter deciduous leaves
Lost in response to onset of fall and winter (lose leaves in fall, store energy/resources in roots, and grow them back in the spring)
Fresh water
Lotic - flowing water (rivers and streams) Lentic -nonflowing water (ponds, lakes, and wetlands)
Arctic Tundra Vegetation
Low ground Vegetation -cotton grasses, sedges, and Sphagnum Well-drained sites -heath shrubs, dwarf willows, birches, herbs, mosses,and lichens Driest and most exposed sites -scattered heaths, crustose and foliose lichen
Grasses
Maintain a higher proportion of biomass in photosyntehtic tissue that shrubs and trees because little energy is required for support tissues -above ground biomass is photosynthetic
Aquatic Ecosystems : Three main types
Marine Freshwater Estuarine -have a range of construction -all aquatic ecosystems are linked directly or indirectly as components of the hydrological cycle
Cross-sectional area = width x average depth
Measuring flow -measure distance across (wide) -measure depth (multiple areas) -->cross sectional area
Shrub-lands (chaparral) Found in the Mediterranean Climates
Mediterranean ecosystems are found along the western margins of the continents between 30 and 40 latitude -dominated by evergreen shrubs and sclerophyllous (small, hard leaves) trees -very dry and prone to cyclic fire Five main regions -western North America -Borders of the Mediterranean Sea -Central Chile -Cape region of South Africa -Southwestern/southern Australia Above the equator - warm, fairly moist Mostly shrub land *don't have to know the regions - just know western North America (such as Nevada) - Shrubs
Estuaries
Mixing waters of different salinities and temperatures creates a counter-flow that works as a nutrient trap -nutrients are carried into the estuary by the tides Estuarine organisms must maintain their position and adjust to the changing salinity Many inhabit the benthos, and those that are mobile can swim against the tide, or move with the tides Most estuarine species are fully marine and cannot withstand lower salinities -sessile and slightly motile organisms have an optimum salinity range and may avoid big changes in salinity by "clamming up" = shutting down activity until favorable conditions return Most productive areas in the world Most of the animals that live there are capable of avoiding fresh and salt water - stop when salt gets too low or high -tides - flush salt water, flush of fresh water *oysters, seagrass
Rivers Flow into the Sea, Forming Estuaries
Most streams and rivers eventually drain into the sea Estuaries are semi-enclosed parts of the coastal ocean where freshwater joins saltwater -the unidirectional inflow of freshwater interacts with the inflowing/outflowing saltwater tides, setting up a complex of currents Concentrations of salt (0) freshwater, (20-30) brackish, (30-35) marine
Dedritic Drainage
Mountains, branches come together like a tree coming into a trunk
Large Scale Patterns of Biological Diversity
Nearly 1.56 million species have been identified and named, though more are discovered each year -wilson suggested that closer to 10 million species exist -species number is an equilibrium between two evolutionary processes: speciation and extinction -means all these species do other things - diversity of function (not just a number of species) -most species that have ever existed are extinct *equilibrium species being evolved and going extinct *all species will eventually become extinct Over evolutionary time, new species evolve while existing species become extinct Selection factors in the specific environments drive speciation and extinction Accounts biological diversity in various geographic regions around the world The number of species has been increasing for the past 600 million years -if you do not evolve you will not survive -selction factors (usually local - works on individuals not on borders) which help individuals adapt to their environment -predation -temperature (etc.) *selection works against things rather than for things -because environments are different around the world and selection is specific to those diversity is similar to those environment types
Example for Mammals
Neartic - carbo, wolves, cougars --> you do not see this in neotropical *no tigers in Africa
Eastern Temperate forest in the US
Oaks need fairly dry climates to survive
Natural Grassland
Occupy regions where rainfall is between 25-80 cm/year -many grasslands exist through the intervention of fire and human activity -natural grasslands have shrunk to less than 12% of their original size Grasslands occur in the mid-latitudes in the midcontinental regions where annual precipitation is reduced Three strata in grasslands -tall, green, ephemeral herbaceous growth -ground layer belowground root layer
Marine (salt water)
Open-water (open ocean) Coastal
Structure of Grass Plant
Prairie grasses grow from roots just underground and are not killed when fires burn their leaves and stem. Also, these grasses survive animal's regular munching - cutting of the blades off just at the ground - because of these underground stems and buds -lots of roots, more biomass in the roots than in the shoots -growing area is in the crown and below Grasses allocate a high proportion of their photosynthate belowground to roots --> greater soil carbon pools Root systems - deeper in the root system than the shoots are tall -lots of underground growth
Biogeographic Realms began forming >135x10^6 years ago
Realms developed in Pangea when separation occurred -separation in continents and evidence of evolution for biota in different parts of the world (65 million years ago)
Stream Network
River order All streams are apart of the network (always something up/down stream) -streams that have no branches are first order
Rectangular Drainage
Rocks
Chaparral
Shrub-lands with fire climax systems 25-30 years for shrubs to grow 5 year drought leading to the drying and burning of shrubs (creating a very good fuel for the fire) Become susceptible to erosion and mudslides (washington to baja) Nothing left to hold the soil - fire climax system
Shrubs and Trees
Shrubs maintain less biomass in stems and other supporting structures than do trees. In trees, the advantage of woody tissues is height and access to light. -most of the biomass is in the trunk and in the branches -differences between shrubs and trees -shrubs have more leaves -trees have more woody tissue to grow taller and have more access to sunlight - less biomass in photosynthetic material than grasses because they need the wood to provide support -trees needs lots of water, grass needs little, shrubs moderate amount Leaf type is a plant characteristic used to further classify forest and woodland ecosystems
Transition from woodland to savanna to grassland in southern Africa depends on rainfall
Soil texture v. Rainfall: helps control what is there Grassland 200 Savanna 200-800 Woodland 800-...
Deserts
Sonoran Gobi Sahara - largest desert Australia
Second largest most continuous rain forest in the world
Southeast Asia
Current Velocity
Speed of water movement (m/sec)
Tall grass prairie (kansas)/Texas
Tall grass prairie - flowers
Largest most continuous rain forest in the world
The Amazon Basin of South America
Deserts: A diverse group of ecosystems
The arid regions of the world occupy 25-35% of the Earth's landmass -distinctive characteristic of all deserts - lack of precipitation Deserts lie between 15 and 30 latitude - Intertropical Convergence Zone (ITCZ) Temperate deserts lie in the rain shadow of mountain barriers or are located far inland -temperate deserts of central asia (eg. Gobi Desert) -Temperate deserts of NA Rain shadow -lots of evaporation and more precipitation on the Eastern side *Sahara - largest desert
Pelagic Communities Vary among the Vertical Zones
The dominant autotrophs in the pelagic zone are phytoplankton restricted to illuminated zone -littoral and neritic waters and regions of upwelling are richer in phytoplankton than are the mid-oceans Shallow coastal autotrophs -attached algae - kelp forests (brown and red algae) Algal beds - Kelp -80 to 90 feet long -otters live there -shallow coastal occupied by kelps Herbivorous zooplankton feed on autotrophs To feed on phytoplankton, most of the grazing herbivores must also be small (.5-5mm) -most grazing herbivores in the oceans are copepods (maybe the most abundant animal in the world) -krill are found in the antarctic - favorite baleen whale food Nekton, swimming organisms, feed on zooplankton and pass energy to hgiher trophic levels -small fish to large sharks Algae and diatoms, grazing animals -copopods - shrimp, krill, baleen whales The microbial loop is the interaction between photosynthetic and heterotrophic bacteria and nanoflagellates -photosynthetic nanoflagellates (2-20um) and cyanobacteria (1-2um) are responsible for a large part of photosynthesis in the sea -Heterotrophic bacteria feed on photosynthates produced by these -Heterotrophic nanoflagellates consume heterotrophic bacteria Also in the ocean - driven by dissolved organic matter
Watershed (drainage Basin) - what is a watershed?
The making of a river An area you can delineate on a map, all the water on the watershed moves/drains into watershed from precipitation (all usually end in same river) -james river -roanoke drainage
The Taiga (boreal forest) is the largest conifer forest and is largest vegetation formation on Earth
The taiga encompasses the high latitudes of the Northern Hemisphere and covers 11% of the Earth's terrestrial surface. The taiga primarily occupies formerly glaciated land and is a region of cold lakes, bogs, rivers, and alder thickets. Three sub-divisions of the Taiga (Ti-ga) -forest-tundra ecotone (northern most) -open lichen woodland -main boreal forest - this grades into the temperate forest to the south Litter inputputs are low but decomposition rates are slow, resulting in an accumulation of organic matter. -high latitudes -covers 11% of the earth -Cold, damp lowlands -in higher elevations you find evergreen trees
Tropical Forests Characterize the Equatorial Zone
The tropical rain forest is dominated by broadleaf evergreen plants. Rain forests are restricted to the equatorial zone between 10N and 10S. Temperatures are warm throughout the year and rainfall occurs almost daily -mean temperature >18C -minimum monthly precipitation >60 mm The amazon basin of South America is the largest and most continuous rain forest in the world. The second largest is in Southeast Asia, and the third largest is in West Africa. **Tropical rain forests account for more than 50% of global biological diversity.** -50% of the global biological diversity is Tropical Rain forests - worlds species that occur in the tropical rainforest -A 10 km^2 area of tropical rain forest may contain 1500 species of flowering plants and up to 750 species of trees -The lowland tropical forest of peninsular Malaysia contains nearly 7900 species (don't have to know) Nearly 90% of all non-human primate species live in the tropical rain forests. High rates of litter fall but litter does not accumulate because decomposition rates are very fast.
Low Precipitation and Cold Temperatures Define the Artic Tundra
The tundra is a frozen plain that is located at the highest latitudes of the Northern Hemisphere -artic Tundra has up to 100% plant coverand wet to moist soils -Polar Desert has less than 5% plant cover and dry soil -Alpine Tundra in high mountains have grasses and flowering shrubs, elevation is too high for trees to inhabit
Forest Ecosystems Dominate the Wetter Regions of the Temperate Zone
There are four vertical layers in deciduous forests that are highly developed and unevenly aged -upper canopy - dominant tree species -lower tree canopy or understory -shrub layer -ground layer of herbs, ferns and mosses
Major Biomes and Biogeographical realms of the world
Tropical and subtropical moist broadleaf forest Tropical and subtropical dry broadleaf forest Tropical and subtropical coniferous forests Temperate broadleaf and mixed forests Temperate coniferous forest Boreal forests/taiga Tropical and subtropical grasslands, savannas, and shrublands Temperate grasslands, savannas, and shrublands Flooded grasslands and savannas Montane grasslands and shrublands Tundra Mediterranean forests, woodlands and scrub Deserts and xeric shrublands Mangroves -biogeographical realm - much larger than biomes correspond with pangea -developed separately as the continents divided -different species in different sanctions Oceania Neartic Neotropic Afrotropic IndoMalav Australasia Antarctic *within biogeographical realms there are biomes
Shifts in terrestrial plant dominance over the last 400 my
Vascular plants - able to conduct water Gymnosperms -pine cones *Angiosperms - dominant and have the most diversity (flowering plants)
Current Velocity and Flow (discharge)
Velocity and Flow are influenced by the shape, steepness (gradient, width, depth, and bottom roughness of the channel As the gradient decreases, stream channels generally get wider and deeper and velocity slows down Discharge (Q) is a product of water velocity X crosssectional area of the channel (WxD) Q=velocity (m/sec) x Area (m^2) = m^3/sec 1 m^3 = 1000 Liters = 263 gal Velocity = how fast/how much is going, speed of movement Flow = discharge, volume of water, cubic meter/sec
Measuring Stream Velocity
Velocity meters River gauge - depth of river, how far the water comes up in the tower Rubber Ducky Method for steam velocity Put a float upstream, measure how long it is, time how long it takes to get back to you -can use oranges, water is slower further down than it is at the top
Radial Drainage
Volcano
Flow/Discharge
Volume of water moving (m^3/sec)
Third largest most continuous rain forest in the world
West Africa
Storm Hydrograph
When it rains, storm hydrograph, water goes up, then goes down after a few days -discharged measured in volume, rainfall coming in, time, baseflow (cubic meters/sec - how fast you're moving) -rain from the watershed more effective than rain directly in stream --> takes time for the water to come through the soil into the stream (rising limb) -peak discharge (highest amount of water) Surface runoff - in the middle of the city -predict flooding by placing gauge down stream Urban Systems -After urbanization without detention basins - not controlling the water -controlled outflow from detention basin or flood control reservoir -prior to urbanization -black top effects rain runoff -detention basin/flood control reservoir (slows water down, goes into the creek gradually)
Estuarine
Where rivers meet the ocean - mouths of rivers as they flow into the ocean (saltwater but at a lower concentration (0-35%) -much less salt than marine, much more salt than fresh water -certain organisms need to be in this system because they cannot have too much or too little salt -some may burrow into the muds
Woodland and Savanna Ecosystems
characterized by the co-dominance of grasses and trees (or shrubs) *savannas, grasslands with scattered trees
Deciduous leaves
live for only a single only a single year or growing season