Unit B Ecosystems and Population Change

Ecosystems and their Diversity

Biosphere

Ecosystems

Community

Population

Organism

Studying Ecosystems Ecosystem

Community of populations together with its abiotic and biotic factors that surround and affect it

Small (lichen covered boulder on a hill side) or large (hill side)

Aquatic and terrestrial

Components of ecosystem

Transition between Ecosystems Ecotone

grey area between ecosystems Transition area where organisms from both

ecosystems interact Lots of species diversity in this region

pond ecotone field

Types of Ecosystems Artificial Ecosystems

Living community is planned or maintained by humans

School yard, local parks, farms, managed forests Natural Ecosystems

Living community is free to interact with physical and chemical environment

not untouched just not planned or maintained by humans

Lakes, rivers, forests, deserts, meadows

Case Study page 88

Terrestrial and Aquatic Ecosystems in Canada Canada has:

2 major Aquatic biomes1. Freshwater

2. Salt water/marine

4 major Terrestrial biomes1. Taiga (most)

2. Tundra (north)

3. Temperate Deciduous Forest (great lakes)

4. Grasslands (prairies)

Terrestrial and Aquatic Ecosystems in Alberta Alberta’s aquatic ecosystems fit into the freshwater

Lakes, rivers, streams, ponds etc Alberta’s terrestrial ecosystems fit into the Taiga

and grassland biomes Taiga (boreal forest) Muskeg (bogs in boreal forest) Grassland Parkland, Foothills (ecotones) Deciduous

Who’s Who and What’s What Use the table of some of abiotic and biotic factors found

in the four major ecosystems of Alberta Take a piece of chart paper and divide the paper into four

quarters and label appropriately

Place each factor in the quarter where you think it belongs be sure to justify

When finished give a brief description of each ecosystem

Taiga GrasslandMuskeg Deciduous Forest

Alberta Ecosystems Ecosyste

mAbiotic factors Biotic community

taiga ● northern and central ● changeable weather● soil contains some water and is acidic● precipitation 50–250 cm/a

black and grizzly bearswolverineweaselsmoosedeergrouseowlsspruce and pine treesshrubs, ferns, mosses, and lichens

muskeg ● cold temperatures ● short growing season ● permafrost layer beneath soil ● low precipitation: 50–150 cm/a

black bearcaribouptarmiganrapidly flowering plants, moss, and lichens

grassland ● central and southern ● more sunlight and warmer temperatures than muskeg or taiga

ecosystems ● rich, fertile soil ● precipitation 25–100 cm/a

bisondeerrabbitshawksyellow-bellied sapsuckersfescue grassesgrasshoppers

deciduous forest

● central ● more sunlight and warmer temperatures than muskeg or taiga

ecosystems● rich, fertile soil ● precipitation 75–250 cm/a

black bearsweaselsmoose deerwoodpeckersdeciduous treesshrubs

Aquatic and Terrestrial Ecosystems Worksheet

How are we doing so far Quiz?

Ecology Now! Magazine Article

Populations A group of organisms of one species that interbreed

and live in the same place at the same time (e.g. deer population).

Studying Populations in Ecosystems

Ecologists sample random populations within ecosystems to collect data that helps them better understand the species Sampling Populations

Count species of a few samples of entire population then average them

TransectsQuadrants

Yeast Population Study

Features of PopulationsPopulations have a number of attributes that may be

of interest to ecologists and we that we can measure during sampling:

Migration Distribution and Abundance Composition Dynamics

Migration Movement of individuals into (immigration) and out

(emigration) of population Affects density, distribution, dynamics and

composition of a population

Population Distribution and Abundance

Tells us more about the numbers of the pop

Density-# of organism per unit area (avg number of individuals per quadrant and dividing by size of quadrant) Total abundance can be determined from this

Distribution-Location of individuals within an area (random, clumped or uniform)

Carrying Capacity-max # of individuals that can be supported

Population CompositionData that enables up to determine whether the pop is

declining or increasing

Sex ratios-# of organisms of each sex Population fertility-reproductive capacity of the females Age structure-# of organisms of different ages Capacity for survival-# of offspring that reach

reproductive age Length of reproductive life-age of sexual maturity & # of

years the individual can reproduce

Biotic Potential What is it?

Population DynamicsInformation that helps us understand what is happening

within the pop

Growth Rate-change in the total population per unit time Birth Rate- # of organisms born per unit time Mortality Rate- # of organisms dying per unit time Breeding Frequency-# of times that a organism

reproduces each year Birth Potential- # of offspring per birth

Population Worksheet

Studying Individual Organisms in Ecosystems

Ecologists study the following to find out more about specific species within a population:

Habitat and Range Ecological Niche Factors that limit growth

Abiotic and biotic factors

Habitat A place or area with a particular set of

characteristics, both biotic & abiotic Each species is found in a specific habitat that its

physical, physiological and behavioural adaptations equip it to survive and reproduce

One large area or a bunch of small areas that are similar

Range Geographical area where the species is found Species will only be found where its habitat is

present

Ecological nicheFunctional position of an organism in its

environment, comprising of its habitat and resources obtained there, and the periods of time which its active

Habitats and Niches in AB ecosystems

terrestrial and aquatic ecosystems can support a diversity of organisms because they have a variety of habitats and niches

Terrestrial Niches/habitats Aquatic Niches/habitats

Terrestrial

Canopy

Understorey

Forest floor

Terrestrial Niches/Habitats Canopy

Upper area of vegetation, lots of sunlight, diverse number of birds

Sub canopy Usually shrubs and smaller trees, many browsers such as

deer and moose

Forest floor Lowest area, continuous shade, shelter nesting sites,

supports many types of insects, shade loving plant

Soil Temperature levels determine decomposition & organic

matter

Aquatic Niches/Habitats

Benthic zone

Aquatic Niches/Habitats (lake) Littoral zone

Shallow, most productive part of the lake, plants and algae take full advantage of sunlight for photosynthesis

Limnetic zone Enough light for photosynthesis to occur, plankton is the food

for the higher level consumers

Profundal zone Not enough light for photosynthesis, not alot of oxygen, carp

and other invertebrates that can handle low o levels

Benthic zone The :ground”, rooted and bottom dwelling organisms, amount

of sunlight and temperature depend on depth of water

What Am I? Worksheet

Factors that affect Ecosystems Web

Limiting Factors Abiotic and biotic conditions that limit the number

of individuals Species cannot grow in an unlimited fashion for a

sustained period of time Control the growth, distribution, survival of a

species Anything in short supply (e.g. nutrients or sunlight)

Abiotic Limiting Factors Soil

Provides nutrients for all plants that grow on land

Determined by nature of rock in which it was formed, nature of plants & H2O acidity

Water (availability, depth of water table, pressure)Organisms need water to surviveDetermined by amount & type of ppt, how

much collects then stays in soil, depth of water

TemperatureAffects other abioitc and biotic factorsVary throughout year

SunlightProvides energy to systemDepends on closeness to equator, seasons

and location in ecosystem Chemical Nutrients

Important to survival of organismsDetermined by seasons, soil, temperature,

, amount dissolved

Biotic Limiting Factors Competition

Intraspecific= members of same population compete with each other for limited resource (food, water, sunlight, mates, shelter, breeding sites etc)

Interspecific= members of two different populations compete (exotic species) resulting in extinction of one or both of the populations

Predators Parasitism=one organism (parasite) derives its

nourishment from another organism (host) which is harmed in some way

Yellow Perch Case Study

How are we doing so far quiz?

Classifying Organisms Scientists use classification system to understand

similarities and differences between species Science of classifying =Taxonomy (Taxonomists)

Levels of Taxa 7 levels of classification

Kingdom Phylum Class Order Family Genus Species

6 Kingdoms Eubacteria Archaebacteria Protista Fungi Plantae Animalia

Kingdom General characteristics Cell wall Representative organisms

Eubacteria ● simple organisms lacking nuclei (prokaryotic)

● either heterotrophs or autotrophs ● all can reproduce asexually● live nearly everywhere

often present (contains peptidoglycan)

bacteria, cyanobacteria

Archaebacteria ● prokaryotic ● heterotrophs ● live in salt lakes, hot springs, animal

guts

present (does not contain peptidoglycan)

methanogens, extreme thermophiles, extreme halophiles

Protista ● most are single celled; some are multicellular organisms; eukaryotic

● some are autotrophs, some are heterotrophs, some are both

● reproduce sexually and asexually ● live in aquatic or moist habitats

absent algae, protozoa

Fungi ● most are multicellular ● all are heterotrophs ● reproduce sexually and asexually ● most are terrestrial

present mushrooms, yeasts, bread moulds

Plantae ● all are multicellular ● all are autotrophs ● reproduce sexually and asexually ● most are terrestrial

present mosses, ferns, conifers, flowering plants

Animalia ● all are multicellular ● all are heterotrophs● most reproduce sexually ● live in terrestrial and aquatic habitats

absent sponges, worms, lobsters, starfish, humans

Binomial Nomenclature Developed by Carl Linneaus as a way to

scientifically name and classify organisms Based on physical and structural features (anatomy,

embryology, and ancestry) More features in common the closer the relation 2 part name (usually Latin)

Genus species

Pg 139

Using a Dichotomous Key Classification manuals that are constructed to help

conduct their identification work A series of choices about the structure of the

organisms must be made and each choice leads to a new branch

If each choice is made correctly then the end result will be the organisms name

The Key1. (a) baleen plates

(b) teeth Go to 2.Go to 4.

2. (a) dorsal fin (b) no dorsal fin

Go to 3.bowhead whale (Balaena mysticetus)

3.(a) long pectoral fin (b) short pectoral fin

humpback whale (Megaptera novaeangline)blue whale (Balaenoptera musculus)

4.(a) no dorsal fin (b) large dorsal fin

Go to 5.killer whale (Orincus orca)

5.(a) small nose (b) large projection from nose

Go to 6.narwhal (Mondon monoceros)

6.(a) mouth on ventral surface (underside) of head(b) mouth at the front of head

sperm whale (Physeter macrocephalus)beluga (Delphinapterus leucas)

Pg 162

Creating and Using a KeyWorksheet