Ecology

What is ecology?

• Ecology= ‘study of house’– Study of interaction among plants, animals,

and the environment

Levels of Organization

• Biosphere– Part of Earth where life exists

• Biome– Area of earth that has similar

geography & climate

• Ecosystem– Living and non-living parts of

an area

• Community– Living part of ecosystem

• Population– Members of the same species

• Species– Population that reproduces in

the same area

Big

Small

Biomes

Biome • Climate (Temp, Precip, Soil)

Flora (plants) & Fauna (Animals)

Tundra Temp:

Precip:

Soil:

Flora:

Fauna:

Taiga/Boreal Forest Temp:

Precip:

Soil:

Flora:

Fauna:

Northwestern Coniferous Forest

• Mild temperature• Cool dry summer, moist

rest of year• Rocky acidic soil

• Flora- Tall trees• Fauna- Varied diet

animals

Temperate Deciduous Forest

Temp:

Precip:

Soil:

Flora:

Fauna:

Biome Abiotic Factors (Temp, precip, soil)

Flora (plants) & Fauna (animals)

Temperate Woodland & Shrubland

• Hot dry summer, cool moist winter

• Thin nutrient poor soil

• Flora- woody chaparral plants- resistant to drought & fire

• Fauna- varied diets

Temperate Grassland

• Warm to hot summers, cold winters

• Moderate seasonal precip

• Fertile soil, occasional fires

• Flora- grasses• Fauna- herbivores-

animals with camouflage to avoid predators

DesertTemp:

Precip:

Soil:

Flora:

Fauna:

Tropical Grassland/Savannah/

Shrubland

Temp:

Precip:

Soil:

Flora:

Fauna:

Biome Abiotic Factors (Temp, Precip, Soil)

Flora (plants) & Fauna (Animals)

Tropical Dry Forest • Warm year-round• Wet & dry seasons• Rich soil subject to

erosion

• Flora- deciduous (drop leaves)

• Fauna- Those that go through estivation- hibernation during dry season

Tropical Rain Forest Temp:

Precip:

Soil:

Flora:

Fauna:

Ecosystems• Ecosystems- non-living & living part of an

area– Abiotic = non-living– Biotic = living

Abiotic Factors: Nutrient CyclesCarbon Oxygen Cycle

Carbon-Released by animals & factory-Consumed by plants

Oxygen-Released by plants-Consumed by animals

Abiotic Factors: Nutrient CycleWater Cycle

• Evaporation: Water atmosphere

• Evapotranspiration: Groundwater plants atmosphere

• Condensation: Formation of cloud water droplets fall to ground groundwater (water in soil & bedrock)

• Runoff: Groundwater lakes & streams

Abiotic Factors: Nutrient CyclingNitrogen Cycle

A & B) Nitrification•Ammonium (NH4

+) Nitrites (NO2

-) Nitrates (NO3-)

PlantsC) Decomposers•Nitrogenous waste Ammonium (NH4

+)D & E) Nitrogen-fixing bacteria• Free Nitrogen Ammonium (NH4

+)•Example: LegumeF) Denitrifying bacteria

• Nitrates (NO3-) Free

nitrogen (N2)A

B

C

D

E

F

Succession

• Disaster followed by increasing numbers of species

• Disasters: Clear land, fire, tree fall, volcano erupts

1. Pioneer organisms- hardiest organisms– Examples: Algae, moss, lichens, bacteria

2. Grasses Shrubs Trees3. Climax community- maximum number of

species sustained by ecosystem

Climax

Communities

• Communities- all the living organisms within a community– Includes different species of organisms

Communities within an Ecosystem: Interactions

• Commensalism– 1 benefits, other unaffected (+/0)– Examples: Hippos & birds; Sucker fish & sharks

• Mutualism– Both benefit (+/+)– Examples: 1. Lichens fungi (moisture) + algae

(food & water) 2. Protazoa (digest) + termites (shelter,

food) 3. Bacteria (converts N) + roots of legume (makes

food)

• Parastism– 1 benefits, other harmed (+/-)– Examples: Athlete’s foot, tapeworm

Interactions within Communities: Cont’d

• Competition- two species in same area require same food, water, and space– Interference competition-

prevent the other species from obtaining the resource

• Example: Physical attack

– Exploitation- indirect competition in which one species uses up resources before the other can

Communities within an Ecosystem: Nutritional Relationships

• Autotroph- produces its own food– Example: Bacteria, plants,

chemophotosynthesis– Also referred to as producers

• Heterotroph- consumers– Eat other animals for food

• Example: humans

Types of Heterotrophs

• Carnivore- eats meat– Includes predators & scavengers

• Predator- cheetah• Scavengers- vultures

• Herbivores- eats plants– Example: Caterpillar

• Omnivore- eat plants and animals– Example: Some humans, bears

• Decomposer- eats dead material– Example: Bacteria, Fungi

Energy Flow in Ecosystems

• Sun is the main source of energy in all ecosystems

• Food chains- linear sequence indicating who eats whom

• Example: Grasses rabbit fox

Food Webs

• More realistic than food chains– Shows more interactions among species

1. Producers (autotrophs/plants)2. Consumers (heterotrophs)

– Primary consumer- herbivore– Secondary and tertiary consumers-

carnivores & omnivores

3. Decomposers (saprophytes) – Example: fungus, bacteria

Energy Pyramids

• Most energy & biomass at the bottom of the pyramid– Each step up the pyramid

is about 1/10th the energy & biomass of the step below it

• Bottom: Producers• Middle: Herbivores• Top: Carnivores• Omnivores: between

herbivores & carnivores

Populations

• Populations- All members of a given species

• Exponential Growth– Represented by J-curve– No limiting resources

• Carrying capacity– The maximum number in a

population that can be sustained by resources in the environment

• Limiting Factors– Amount of nutrients and

food available for population

The Human Population

• Thomas Malthus– Economist who stated

food supply is the human limiting factor

• Other limiting factors• War, diseases, global

warming, water availability

• Solutions– Hydroponics, crop

rotation

Species

• Species: Organisms in the same area that are able to reproduce

• Species occupy niches• Niche- role within the

ecosystem• Fundamental niche-

where a species exists based on abiotic factors

• Realized niche- where a species exists based on biotic factors

Biodiversity

• Biodiversity- number of species in a given area– Greater biodiversity, greater stability in

ecosystem– Question: Does biodiversity relate to

communities or populations?

________________________________

Positive Human Impact on the Environment

• Population control– Limit number of children

• Conservation of resources– Plant trees, reduce soil erosion, water

• Pollution control– Scrubbers

• Species preservation– Refuges, national parks, state parks

Positive Human Impact on Environment

• Use of biological controls– Integrated pest management (IPM)– Introduce natural predator

• State environment protection laws– Freshwater & wetland act

• Federal environmental protection laws

Negative Human Impact on Environment

• Overconsumption– Water, food, oil

• Adverse effects of technology– Need for natural resources– Water pollution

• Factories dump PCBs & heat

– Air pollution• Acid rain

– Burn coal & oil– Get sulfur dioxide

– Pesticides– Waste

Rank Country Electricity - consumption (billion kWh)

1 United States 3,892                                                     

2 China 3,271                                             

3 Japan 1,080               

4 Russia 1,003              

5 Germany 549.1        

6 Canada 530        

7 India 517.2        

8 France 480       

9 Brazil 402.2      

10 Korea, South 385.1      

11 United Kingdom 348.5     

12 Italy 316.3     

13 Spain 276.1    

14 South Africa 241.4    

15 Taiwan 233    

Rank Country Oil - consumption (bbl/day)

1 United States 20,800,000                                                     

2 China 6,930,000                  

3 Japan 5,353,000              

4 Russia 2,916,000        

5 Germany 2,618,000       

6 India 2,438,000       

7 Canada 2,290,000      

8 Korea, South 2,130,000      

9 Brazil 2,100,000      

10 Mexico 2,078,000      

11 Saudi Arabia 2,000,000      

12 France 1,999,000      

13 United Kingdom 1,820,000     

14 Italy 1,732,000     

15 Iran 1,630,000     

Negative Human Impact on Environment

• Poor land management– Need more cities, less

sprawl

• Importation of organisms– Bring in pests– Example: Gypsy moth,

zebra mussels, kudzoo

• Exploitation of Wildlife– Excessive hunting of furs &

tusks

Result of Negative Human Impact

• Global instability & reduced biodiversity

• Biodiversity= number of species in a given area

• Greater biodiversity, greater environmental stability

Negative impact is irreversible!

Global Warming• Increased ________ ___________ gas in atmosphere– Caused by burning _______

__________ emitted from cars, factories, electricity, & ______ & ______ forests worldwide

• These activities add CO2 _________ than the carbon cycle _______ it

• Carbon acts as an insulating blanket

WARMER!

Pg. 178

Global Warming: Abiotic Results• Shifting climate patterns

– Changes in patterns of ___________ & _________

– More intense storms in one area, drier climate in another

– Warmer closer to the _____ ______

• Alaska temp increased _____° C over last ___ years

– Ocean currents shifting– Rising ________ _______

• Caused by ________ _________, ____ _____, polar ice sheets

Pg. 177

Global Warming: Cont’d

• Effects on organisms– Migration north to ______ climates, or to

_________ altitudes– Animals behave as if spring were _________– Endangered & extinct species

Pg. 178

Ozone• Ozone layer- consists of O3

• Normally a pollutant at ground level, but in the atmosphere, it absorbs _____ ________

• UV radiation causes ______, damage to _____, lower resistance to ______

• Can also damage _____ & _____

Pg. 175

Hole in the Ozone Layer

• Cause:

• Gases called _____ damage ozone layer

• Used in ____ ________, coolant in _____, _________, ___ __________, and production of plastic ______

Pg. 175

Ozone: Changing Behavior

• Set new policy

• Montreal Protocol: _______ use of CFC’s

• Levels of ___ have _______ since the protocol

• The hole should disappear around __________

Pg. 175

Questions to Ask

• When will our advancing technology stop working?

• How can we take action?

• How is my generation having an impact on the environment?