I Biology I Lecture Outline Ecology
References (Textbook -pages 818, 837-926)
Definitions
History
Levels of Study
1. Population Ecology
A. Definition and Overview
B. Examples of Population Ecology Studies
2. Community Ecology
A. Definition and Overview
B. Examples of Community Ecology Studies
3. Ecosystem Ecology
A. Definition and Overview
B. Examples of Ecosystem Studies
4. The Biosphere
A. Definition and Overview
B. Examples of Biosphere Studies I Biology I Lecture Notes Ecology
References (Textbook -pages 818, 837-926)
Definitions
1. Your textbook defmes ecology as the study ojthe interactions ojorganisms with other organisms and with the physical and chemical environment.
2. The word ecology is derived from the Greek word "oikos" that means house or home.
3. In a simplistic way one could say ecology is the study of the house or home ofLife on earth.
4. Ecology is a basic division of the Science ofBiology much like Botany and Zoology.
History
I. Anton van Leeuwenhoek a Dutch shopkeeper studied "jood chains" and "population regulation" in the early 1700's.
l.uuw~lfhoek "JlSuaJJy rl!rtfOftlN!"-d ID lire ~fa1"er ofille microscope". H~ built th~ first microscope and was probobly thefirst peT.WIf to ~ee ceIb wing /I microscope.
2. Ernst Baeckel, a German Biologists,jirst used the word ecology in 1866.
3. Ecology did not mature into a distinctfudd ofstudy lUltil the early 1900's.
4. During the 1960's, ecology finally became part of the general public vocabulary and a distinct curriculum at universities in the U.S. and elsewhere. Levels of Study (see handout ofTable 46.1 Ecological Terms from page 438 oflatbook)
• One of the most common ways scientists approach the study ofecology is to hreak it down into what are called "levels oforganization".
• We studied "levels oforganizahon" in a single animal and found the following progression.
CELLS-TISSUES-ORGANS-ORGANSYSTEMS- --- ORGANISM
• We can continue the progression and do something similar for the study of ecology.
ORGAN1SM-POPULATlON-COMMUN1TY-ECOSYSTEM- -- BIOSPHERE
• We will cover these levels using the titles
Population Ecology Community Ecology Ecosystem Ecology The Biosphere
1. PopulationEcology
A. Definition and Overview
• Population Ecology is defined as the study ofa group oforganisms of the same species occupying a certain geographic area and sharing a common gene pooL
• Population is a word normally used to denote a group of people in a given area. (E:xImtpIn indutk lire population ofTTmlon, tire populaJion ofGiMon County, or tire popuialion ofTennLSUL)
• In ecology the word is used in a similar way. B. Examples of Population Ecology Studies
• Population Densities.
(1) Whitetail Deer population estimates for TWRA's Hom Bluff Wildlife Management Area
(2) Whitetail Deer population estimates for the State ofTennessee
• Population Growth Rates.
(1) Depends on birth rates, death rates, emigration, and immigration.
(2) Includes studies measuring increase or decrease in population densities over time in a particular area
(3) For hypothetical example - a study that found that the human population growth rate in Gibson County to be a 5% increase each year from 1990 to 2000.
• DispersaJ Patterns.
( 1) Dispersal patterns represent how individuals of a species are distributed across a geographic area.
(2) There are 3 basic dispersal patterns. (DrawollblacA;board)
CLUMPED RANDOM UNIFORM
----~.~a~.~------7 / ... ..~ / ,,.. 0,,· ' .• ~o /_---- .~_. ' , " (}« l-t r .,. , {P! i D( -: U! ~ (. (P ~ '1 t-. -1'" - J fill f::: ~rq , Tzr I ,"'" _::. J .::> • Life History Studies. (I) Example would be a Life History Study of the Bald Eagle that answered such questions as When do they mate? How long do they live? What do they eat? How many eggs does a female lay? Etc, Etc. 2. Community Ecology A. Definition and Overview • Community Ecology is defined as the studies ofan assemblage of populations interacting with one another within the same environment • Assemblage ofpopulations is a fancy wt9' ofsaying a group of species. • The community includes all populations in a given geograph.ic area. B. Examples of Community Ecology Stndies • Community Composition. (1) Checklist of Aquatic Plant Species of Reelfoot Lake. (2) Checklist of Salamanders of the Spruce-Fir Forests in Great Smoky Mountains. • Community Species Diversity andAbundance. (l) Checklist and Relative Abundance of Aquatic Plant Species of Reelfoot Lake. (2) Checklist and Relative Abundance of Salamanders of the Spruce Fir Forests in the Great Smoky Mountains. • Competitive Relationships. (I) Displacement of Fox Squirrels by Gray Squirrels in Gibson County Tennessee. • Predator - Prey Relationships. (I) impacts ofCoyotes on Wild Turkey Population in Shelby Forest State Park. 3. Ecosystem Ecology A. Definition and Overview • Ecosystem is defmed as - a community and its physical environment including both nonliving (abiotic) and living (biotic) components. • Therefore Ecosystem Ecology can be defined as - the study ofthe interrelationships ofa community and its physical environment including both nonliving (abiotic) and living (biotic) components. • By adding the physical environment, this level is given a whole new dimension to study. • The physical environment brings on new characteristics to study and measure. These include phenomena such as energy flows and biochemical cycles. (see handout ofFigure 48.3 NaJure ofan ecosystem from page &85 ofU!Xtbool) B. Examples of Ecosystem Studies • Energy Food Web or Energy Web Studies. (I) (see handout ofFigure 48.5 Grazing and detritalfood web from page 8860/ lextbool). Taken from studies ofa/oust in New Hampshire. (2) As stated in the legend of the Figure, this is a study of who eats whom. • Ecological Pyramids. (I) (s~~ htlIIdout ofFigure 48.6Ecologica/ Pyramidfrom page 887 oftextbook) (2) This represents a study were producers and consumers were divided into 4 trophic levels (trophic means feeding). These included Autotrophs (producers) Herbivores (consumers) Carnivores (consumers) Top Carnivores (consumers) (3) Note the loss ofbiomtlSS from bottom to top. (610_ - is the rIIlIrtbn 0/organisms nwllip/ied by th~ dry wdglft%rgllJ'lic fNdJU wi,IIill olle orgattism) • Biochemical Cycles. (1) The Carbon Cycle - (su handout ofFiguN! 48.9 The carbon cycl~ from page 890 oftextbook). Note that the transfer ofcarbon into the atmosphere due to respiration approximately matches withdrawal ofcarbon from the atmosphere due to photosynthesis. (2) Other important cycles shown in your textbook include • Water Cycle (see handout ofFigure 48.8 The hydr%gic(woler cycle) from page 889 oftextbook) • Nitrogen CycJe(see handout of Figu,~ 48.11The nitrogen cyclefrom page 891 oftextbook) • Phosphorus Cycle(see handoul ofFigure 48.14 The phosphorus cycle from page 894 oftextbook) 4. Tbe Biospbere A. Defmition and Overview • Biosphere is defined as - 'Zone ofair, land, and water aJ the surface ofthe earth in which all living organisms are found. • Therefore Biosphere Ecology can be defined as - the study of interactions ofaU the earth's organisms with the air, land, and water at the surface ofthe earth. • In an imaginative way - you can think ofthe earth's biosphere as a single, very large organism, with lots ofcomplicated parts and interactions. Each individual part has afunction that may be important for the survival ofthe whole. B. Examples of Biosphere Studies • Climate Studies. (1) Current studies ofglobal warming are examples of biosphere studies. • Classification and Distribution ofBiomes. (1) (see hll1ldoul ofTable 49.1 Selected biomnfrom page 905 oftextbook) and (see hll1ldout ofFigure 49.4 Pattern ofblome distribution from JHlge 904 oftextbook) (2) Biome is defined as a major type ofterrestrial ecosystem. l TAB L E 46. 1 : ~;' Ecological Terms Term De finition Ecology Study of the interactions of organisms with each other and with the physical environment Population All the members of the same species that inhabit a particular area Community All the populations round in a particular area Ecosystem A community and its physical environment. including both nonliving (abiotic) and living (biotic) components Biosphere All the communities on Earth whose members exlu in air and water and on land sofar energy heal / energy heal <{:a-r::~ ..:::.+ ~ nutr i ent s FIGURE .J 8.3 Nature of an ecosystem. C hemicals cycle. bur energy flo ws through an ecosystem. As energy [ran,formation, repeatedly occur, all the energy derived from the sun eventually diSSipates as heat. .\'86 Autotroph. Herbivores/Omnivores Carnivores fungi and bacteria shreVlS - Jetritus food web FIGURE 18.5 Grazing and detrital food web. =:'Jd webs are descriptions of who eats v,I hcm . a... Tan rr o,,'/s :lI ustrt!:e pc ssib'e g-::um '-:)c c ·.·.. eos. F:):"" 2xaT ~ e. J -di. :~ I- C'; : ~ e ci Or" '"' J{S. rT' 2.y be e :.H:en by a hawk. -=.. _:o[rophs such as (he tree are producers dkst trophic. or feedl rg. e'... e . tr~ fi rst S:E! r es of i:'Jrra S :l-e :lnrary ccns,u r-: e"s ,iecor o r.-c ph,c levell, and t e next group of ' '''' '11 als are secondary consumers {third ( rcph lC ievel ). b. G ; een ar r o'.vs u S \:~ ( 2: :'OS5 DIe d e tr ' ~a t :..: cd -,-,eb s. .vr (1 ;.egu"· 'N : - c cr. :- : c." s-r;"e 'jJ:creria ar. d fungi of decay 1-d -' -"!fTlains of dead organisms. A large por:ic n of rrese r~ rr a:n 5i are .f.... orr ere g;-;UJ rg feed ·•·.. eb dl ,_so"',::::ed ir a .. Tre c"' -;:3r sr'!O In ~re certital :ood web are sometimes :~ nimals in [he grazing food '..... eb. as w hen ro:,ins feed en e..Jr..:n \·JO~f'!"S. '7"ht,;s . c. L..e gl""3.2 ir- g foad 'Neb 3r e ~:"e de:-ltal (::0-: ·.. ~ ~b are connec ed to one another. FIGURE 48.6 Eco&ogk:aI pjramid. The biomass, or dry weight (gJm'), for trophic levels in a grazing food web in a bog at Silver Spnngs. Florida. There is a shaqJ drop in bioousl between rhe producer 14'!'IIeI and herl>iYore Ievef, which Is consistent with !he common knowledge thai: the dea-taI rood web plays a significant role in bogs.. -is- I() r .-\RT VIII BIH.·\\I The Carbon Cycle Living and deCld oroanjsms contain organic carbon cl Tn the carbon cycle, organisms exchange carbondioxide with serve as one of the reservoirs for the carbon cycle. The warl( the atmosphere (Fig. -\.8.9). On land, plants take up carbon biotic components, particularly trees, contain 800 billion to. ioxide from the -:::::::======~-...... combustion CO2 in Atmosphere 5 720 Selected Biomes Name Charaereristics Tundra Around North Pole; average annual temperature is - 12C' to - 6C ; low annual precipitation (less than 25 cm); permafrost (permanent ice) year-roundI within a meter of surface. Taiga Large northern biome that circles just below (coniferous the Arctic Circle; temperature is below freezing for forest) half the year; moderate annual precipitation (30-85 cm); long nights in winter and long days in summer. Temperate Eastern half of United States. Canada. Europe. and deciduous parts of Russia; four seasons of the year with hot forest summe rs and cold winters; goodly annual precipitation (7S-150 em) I Grasslands Called prairies in North America. savannas in Africa. I pampas in South America. steppes In Europe; hot in summer and cold in winter (United States); m~te annual precipitation; good soil for agriculture. Tropical rain Located near the equator In Latin America. forests Southeast Asia. and West Africa; wann ( 2~25Cj and wet (190 cmJyear); has wet/dry season. Deserts Northern and Southern Hemispheres at 30" latirude;! hot (38Cj days and cold (7Cj nights; low annual precipitation (less than 25 em). o polar ice o tundra _ taiga o mountain zone • temperate deciduous forest • temperate rain larest • tropical deciduous forest o tropical seasonal forest tropical rain forest o shrubland o temperate grassland , ... -'Ivanna 'idesert rt