ECOSYSTEMS: COMPONENTS, ENERGY

FLOW & MATTER CYCLING

CHAPTER 4

ECOLOGY

Study of the relationships between organisms and their environment– How organisms interact with their nonliving

environment such as sunlight, temperature, moisture, nutrients, etc.

KEY WORK IS: INTERACT - Connections in Nature

What is an organism? What make up organisms?

Organisms are either:

EUCARYOTIC -– SURROUNDED BY A

MEMBRANE

– HAVE A DISTINCT NUCLEUS

– HAVE INTERNAL ORGANELLES

– All organisms except bacteria.

PROCARYOTIC -– SURROUNDED BY A

MEMBRANE

– NO DISTINCT NUCLEUS

– NO INTERNAL PARTS SURROUNDED BY MEMBRANES

– Bacteria

What is a SPECIES? How do species

differ? What is the difference

between sexual and asexual reproduction?

Number of species on earth is not known– 5 million to 100 million

maybe

Wild species - found in natural habitat

Domestic species - have been taken and therefore play a smaller role.

Population

A group of organisms of the same species in a given area at a given time– Can vary with:

• Season

• Time of day

• Time of year

Density = number of organisms/area What is genetic diversity?

What is habitat?

Where an organism lives

What is a Community?

Populations of all species in a particular place at a particular time.

What is an Ecosystem?

Community of different species interacting with one another and with their nonliving environments.

Ecosystems can be small or large. What is the Biosphere?

lithosphere

hydrosphere

Atmosphere

Make up the Biosphere

What makes up the Atmosphere?

Troposphere - 0-11 miles up - contains our air.– What are the major gases that make up the air

we breathe?

Stratosphere - 11-30 miles up - lowest portion contains the ozone layer– What is the purpose of the ozone layer?

What is the Hydrosphere?

Liquid water - surface and underground Ice Water vapor in the atmosphere

Interior of earth:

Core - mostly iron, some nickel– Center solid surrounded by a liquid core of

molten material

Mantle - mainly iron with some Si, O,& Mg– Mostly solid rock except for asthenosphere

which flows like plastic.

Crust - thinnest zone - 98% of it is only 8 elements

Life is sustained by:

One -way flow of energy - from sun through plants to animals - then back into space

Cycling of matter or nutrients Gravity - allows planet to hold its

atmosphere. Earth is a closed system - receives energy

from sun but loses no matter into space– Nutrients are recycled

Organisms are open systems - exchange matter and energy between the system and the environment.– Take in matter and energy - use it to stay alive

and put waste back into the environment.

How does the sun sustain life?

Lights & warms the planet Supplies energy for photosynthesis Powers cycling of matter Drives the climate and weather systems

Facts about the sun

Middle- aged star Takes 8 minutes for light to get to the earth Most of light to earth is ultraviolet About 28% of its light is reflected back into space

by clouds, dust, and land 72% warms air and land, evaporates water, generates

winds, Only about .023% is used by plants for

photosynthesis

Nutrient cycles

Nutrient - any atom, ion or molecule an organism needs to live

Macronutrients are needed in large amounts - CHONPS and a few others

Micronutrients - needed in small or trace amounts.

Also called Biogeochemical cycles. - life - earth - chemical cycles.– Driven by the sun

– Main ones are hydrologic, nitrogen,carbon, phosphorus, and sulfur.

Ecosystem Concepts

Biomes - large regions characterized by climate and life-forms - especially vegetation

Climate - long term weather - mainly temperature and precipitation.

Aquatic life zones - freshwater & marine– Lakes & streams

– Estuaries, coastlines, coral reefs, & deep ocean.

Ecosystem concepts

Ecotone - a region where two ecosystems meet.– Has more species

diversity than either adjacent ecosystem.

Biotic - living components - plants and animals

Abiotic - nonliving components - water, nutrients, air, solar energy, etc.

Range of Tolerance

Ability to survive within variations of a physical or chemical environment– Individuals within a population may have

differing ranges of tolerance

Tolerance limits - beyond which no member of a species is able to survive

Po

pu

lati

on

Siz

e

Low High Temperature

Zone ofintolerance

Zone ofphysiological stress

Optimum range Zone ofphysiological stress

Zone ofintolerance

Noorganisms

Feworganisms

Lower limitof tolerance

Abundance of organismsFew

organismsNo

organisms

Upper limitof tolerance

Range of Tolerance

Limiting Factors

Any one factor that is responsible for regulating population growth– Light, water– In aquatic ecosystems

• D.O.

• Sunlight

• Temperature

What is photosynthesis?

The producers (plants) also called autotrophs take carbon dioxide, water, and sunlight and produce glucose and oxygen.

Chemosynthesis in the ocean uses heat energy from the thermal vents to convert dissolved hydrogen sulfide and carbon dioxide into organic nutrient molecules.

What is trophic level?

The feeding level of the organism.

Plants are __________________ They are the __________________

in an ecosystem. They occupy the _______________ Trophic level.

Cows are __________________ which are ________________

Consumers. They occupy the ______________

Trophic level.

Lions are __________________ They are _____________ Consumers. They occupy the ___________trophic

level.

Pigs are _______ Which means they eat ______and ______;

Sharks are ______ Which means they eat __________

What are DETRITIVORES? What are

decomposers?

What are detritus feeders?

What is AEROBIC RESPIRATION?

Uses _____ + ______ and release _____ ,_______ ______, and _______

What is AEROBIC RESPIRATION?

Uses glucose + oxygen and release carbon dioxide, water, and energy.

All organisms carry on respiration!!!

What is Anaerobic Respiration?

Also called fermentation. Does not use free oxygen The end produces are compounds such as

methane gas, ethyl alcohol, acetic acid, and hydrogen sulfide.