ECOLOGY

THE BIOSPHERE:

• all life on Earth and all the parts of the Earth where life exists

• Ecology is the study of the interactions of all of the organisms and their environments in the biosphere

• There is an interdependence between organisms and their environment.

LEVELS OF ORGANIZATION IN THE BIOSPHERE

1. Organism- one individual of a certain species

2. Population- group of individuals of the same species living in the same area

3. Community- different populations living together in the same area

4. Ecosystem- all the organisms in a certain place together with their physical environment

5. Biome- a group of ecosystems with similar climates and typical organisms

6. The Biosphere- the part of earth in which life exists (land, air, water)

• Where is the biosphere located and what does it include?• The biosphere is everywhere on our planet where

there is life. This can be far above the land where birds fly, deep into the oceans where sea creatures live, or even deep underground where extreme bacteria can inhabit vents and volcanoes. It includes all the living things and the abiotic features of the planet that they interact with and rely upon.

• Because there is life nearly everywhere on Earth, the word biosphere is a very broad term and the Earth itself is essentially our biosphere.

ENVIRONMENTS:

• The conditions or factors surrounding an organism

• Consist of biotic and abiotic factors

BIOTIC FACTORS

• Any living part of the environment

• Includes animals, plants, fungi, bacteria, etc.

• pine tree, • mushroom in soil, • fish swimming in lake

ABIOTIC FACTORS

• Any nonliving (physical) part of the environment

• Examples: sunlight, heat, precipitation, humidity, wind, water, soil, etc.

• Rocks• Waterfall• Clouds

WHAT ARE THE BIOTIC AND ABIOTIC FACTORS IN THIS ENVIRONMENT?

BIOTIC AND ABIOTIC FACTORS ARE CLOSELY LINKED

The mucky shoreline – is it biotic, abiotic or both?Both! Abiotic- soil, water, sand, etc. Biotic- bacteria, fungi, small animals like worms, etc.

ENERGY, PRODUCERS, AND CONSUMERS

At the core of every organism’s interaction with the environment is its need for energy to power life’s processes. You may wonder where energy in living systems comes from and how it is transferred from one organism to another…

For most life on earth, sunlight is the ultimate energy source.

Autotroph:Organism that is able to capture energy from sunlight or

chemicals and use it to produce its own food from inorganic compounds

What are two synonyms for an autotroph?ProducerPrimary producer

Autotrophs are essential for the flow of energy through the biosphere because they are the first producers of energy-rich compounds that are later used by other organisms.

Autotrophs can perform either photosynthesis or chemosynthesis.

Autotrophs can perform…

Photosynthesis Chemosynthesis Process used by plants

and other autotrophs to capture light energy and use it to power chemical reactions that convert carbon dioxide and water into oxygen and energy-rich carbohydrates such as sugars and starches.

Examplesplants, cyanobacteria,

algae, some protists

Process in which chemical energy is used to produce carbohydrates

Examples of chemosynthetic organisms:certain bacteria that

live around deep-sea volcanic vents or hot springs or coastal tidal marshes.

Heterotroph Heterotroph:

organism that obtains food by consuming other living thingsWhat is a synonym for a heterotroph?

consumerHeterotrophy can take several forms – examples of different

ways that consumers can acquire energy and nutrients include…Carnivores- kill and eat other animalsHerbivores- eat plant materialsOmnivores- eat both plant and animal materialsScavengers- consume carcasses of organisms that have

died or that were killed by predatorsDecomposers- feed by chemically breaking down organic

matter into detritus, debris from decomposing plants and animals (Ex: fungi and bacteria)

Detritivores- feed on detritus particles (Ex: earthworms)

In every ecosystem, primary producers and consumers are linked through FEEDING

relationships. Though there is a wide variety of feeding

relationships in various ecosystems, energy flows through an ecosystem in a ONE-WAY stream, from primary producers to various

consumers.

ENERGY FLOW IN ECOSYSTEMS

What is the difference between a food chain and a food web

A food web shows many interconnected feeding relationships – only one sequence of feedings is shown in a food chain.

What is the importance of decomposers and detritivores in a food web?

They convert dead material to detritus, which is eaten by detritivores. This releases nutrients that can be used by primary producers. Decomposers recycle nutrients in food webs rather than leaving them locked within dead organisms

Food Web DisturbancesHow would a decrease in the krill population

affect the Antarctic food web?What do ecologists mean when they say that

killer whales indirectly depend on krill for survival?

Trophic LevelTrophic Level

each step in a food chain or food web

Which trophic level always includes primary producers?The first TL

Which type of organisms occupy all the other trophic levels?various consumers (carnivores, omnivores,

etc)

One way to illustrate the trophic levels in an ecosystem is with an ecological pyramid.

Ecological Pyramids Pyramids of Energy

Show the relative amount of energy or matter contained within each trophic level in a given food chain or food web.

Show the relative amount of energy available at each trophic level of a food chain or web.

On average…

10 percent of the energy available within one trophic level is transferred to the next trophic level.

Pyramids of Biomass and Numbers

 Biomass:the total amount of

living tissue within a given trophic level

Biomass is usually measured in grams of organic matter per unit area

The amount of biomass a given trophic level can support is determined, in part, by the amount of energy available.

Pyramid of Biomass shows:the relative amount of

living organic matter available at each trophic level in an ecosystem.

Pyramid of Numbers shows:the relative number of

individual organisms at each trophic level in an ecosystem.

In most ecosystems, the shape of the pyramid of numbers is similar to the shape of the pyramid of biomass for the same ecosystem. In this shape, the numbers of individuals on each level DECREASE from the level below it.

What might cause an Inverted Pyramid of Numbers?

CYCLES OF MATTER

• What are our 4 main biological elements that make up living things???• H, O, N, C

• Other elements we find…• Sulfur and Phosphorus (REMEMBER: CHNOPS)

• These elements make up the basis of what compounds???• Water, Carbohydrates, Lipids, Nucleic Acids, & Proteins

In other words, a handful of elements combine to form the building blocks of all known organisms – however, organisms cannot

manufacture these elements and do not ‘use them up’ – you may wonder where these

essential elements come from and how their availability affects ecosystems.

ENERGY AND MATTER

• Earth – • a lot of energy on earth is in the form of sunlight entering

the biosphere. BUT earth does NOT receive a steady supply of new matter from space.

• Unlike the one-way flow of energy, matter is recycled within and between ecosystems.

Nutrients are recycled through biogeochemical cycles. These cycles are powered by the one-way flow of energy through the biosphere.

BIOGEOCHEMICAL CYCLE

• Definition:• Process in which elements, chemical compounds, and

other forms of matter are passed from one organism to another and from one part of the biosphere to another

• As matter moves through these cycles it is transformed which means that it is never created or destroyed, just changed.

• Many classifications for these cycles…

Biological Processes

• Any and all activities performed by living organisms

• Examples: eating, breathing, burning food, eliminating waste

Geological Processes

• Volcanic eruptions

• Formation & breakdown of rock

• Major movements of matter within and below the surface of the earth

Chemical/Physical Processes

• Formation of Clouds and precipitation

• Flow of running water

• Lightening

Human Activity

• Mining• Burning of Fossil

Fuels• Clearing of land

for building/farming

• Burning forests• Manufacturing• Use of fertilizers

THE WATER CYCLEH 2 O

THE WATER CYCLE

• Water continuously moves between• Oceans• The Atmosphere• Land• Sometimes outside living organisms and sometimes

inside them…

• Water (H2O) is one of the few substances that occurs commonly in all 3 states on Earth.• Solid, Liquid, Gas

How does Water Vapor (Gas) enter the atmosphere?!?

Water turns to a gas by…• Evaporation

• Evaporating from the ocean or other bodies of water.

• Transpiration• Evaporating from the leaves of plants

• Combustion• Burning of fuels produces water (& CO2)

• Respiration• Cellular respiration by ALL organisms produces water (& CO2)

Once water vapor is in the atmosphere, winds can transport it over great

distances…FOUR MAIN WAYS

• Condensation• When water vapor cools,

the vapor condenses into tiny droplets (liquid) that form clouds.

• Precipitation• When the droplets of water

in clouds become large enough, they fall to the Earth’s surface as precipitation in the form of: • Rain• Snow• Sleet• Hail

• Runoff• On land, some precipitation

flows along the surface, in what is called ‘runoff,’ until it enters a river/stream that carries it to an ocean/lake.

• Groundwater• Precipitation can also be

absorbed into the soil and then it is called groundwater which can enter plants through their roots, or flow into rivers/streams/lakes/oceans. Some can even become part of underground reservoir

THE WATER CYCLE

NUTRIENT CYCLESC H E M I C A L S U BS TA N C E S T H AT A N O R G A N I S M N E E D S T O

S U RV I V E

WHY DOES EVERY ORGANISM NEED NUTRIENTS?

• It’s obvious guys…

• TO LIVE LIFE! • Carry out life processes

• TO BUILD TISSUES

• Like water, nutrients pass through organisms and the environment through biogeochemical cycles

• THREE of these that are especially critical for life are cycles that move carbon and nitrogen and phosphorus through the biosphere.

What is the role of Oxygen in the common biogeochemical

cycles on earth?

BY COMBIN ING WITH THESE ELEMENTS AND CYCL ING THEM THROUGH PARTS OF THE IR JOURNEYS . IT IS A

PRODUCT OF PHOTOSYNTHES IS AND IS USED IN CELLUL AR RESP IRAT ION BY MOST ORGANISMS

THE CARBON CYCLE

THE CARBON CYCLE

• Carbon is a major component of all organic compounds.

• Important in SOME inorganic compounds such as:• Calcium Carbonate

• CaCO3

• Part of different kinds of animal skeletons

• Carbon Dioxide• CO2

• Major part of the atmosphere & necessary for photosynthesis

FOSSIL FUELS

• Some carbon containing compounds that were once part of ancient forests, marine organisms, or other animals have been buried/transformed into energy-rich fuels such as …• Coal• Oil• Natural Gas

• Flashback question --

Nonrenewable or Renewable

Resource???

MAJOR RESERVOIRS OF CARBON IN THE BIOSPHERE INCLUDE…

• Atmosphere• Oceans• Rocks• Fossil Fuels• Forests

THE CARBON CYCLE

• Carbon dioxide is continuously exchanged between the atmosphere and oceans through chemical and physical processes.

• Plants take in CO2 during photosynthesis and use the carbon to build carbohydrates. • These nutrients then pass through food webs to

consumers • Many animals combine carbon with calcium and oxygen

as they build their skeletons.

• Organisms release carbon in the form of CO2 gas by respiration

THE CARBON CYCLE

• When organisms die, decomposers break down the bodies, releasing carbon to the environment.

• Geologic forces can turn accumulated carbon into carbon-containing rocks or fossil fuels.

• CO2 is released into the atmosphere by:• Volcanic Activity • Human Activity • such as: the burning of fossil fuels and the clearing and

burning of forests.

THINK!

What role do you think Decomposers play in the cycling of

Carbon & Oxygen in the biosphere?

Decomposers USE oxygen and PRODUCE carbon dioxide.

They help recycle Carbon and Oxygen by returning these elements to the biosphere so that they are available for organisms to use again.

THE CARBON CYCLE

THE NITROGEN CYCLE

• All organisms require NITROGEN to build amino acids and nucleic acids so that organisms can build DNA, RNA and proteins.

•  Many different forms of nitrogen occur naturally in the biosphere.

• Nitrogen gas• Makes up 78% of earth’s atmosphere

• Ammonia, Nitrate, and Nitrite Ions:• Found in soil, in the wastes produced by many

organisms, and in dead and decaying organic matter.

• Dissolved nitrogen:• Exists in several forms in the ocean and other large

water bodies

BACTERIA

• Although nitrogen gas is the most abundant form of nitrogen on Earth, only a handful of organisms – certain types of bacteria – can use this form directly.

• Because they “lock” (=fix) the nitrogen into usable forms, these nitrogen-fixing bacteria are an essential part of the nitrogen cycle.

NITROGEN FIXATION

• In this process, certain types of bacteria convert nitrogen gas into ammonia. • Some of these

bacteria live in the soil whereas others live on the roots of certain plants called legumes

• Ex: peanuts, peas, soybeans

• Then, other bacteria convert that fixed nitrogen into nitrates and nitrites. Once these forms of nitrogen are available, primary producers can use them to make proteins & nucleic acids

• Consumers eat the producers and reuse nitrogen to make their own nitrogen-containing compounds.

• Decomposers release nitrogen from waste and dead organisms as ammonia, nitrates, and nitrites that producers may take up again.

• Denitrification• Other bacteria obtain energy by converting Nitrates into

Nitrogen Gas, which is then released into the atmosphere.

• Atmospheric Nitrogen Fixation• A relatively small amount of nitrogen gas is converted to

usable forms by lightening

THINK!

 

How do humans add Nitrogen to the

Biosphere?

• Through the manufacture & use of fertilizers.

• Excess fertilizer is often carried into surface water or groundwater by precipitation.

NICHE RECAP…• Niche

• The range of physical and biological conditions in which a species lives and the way the species obtains what it needs to survive and reproduce

Resources

• Any necessity of life such as: Nutrients, Light, Food, or Space

Physical

• Abiotic Factors it requires for survival

• Such as water, temp, light

Biological

• Biotic Factors it requires for survival

• Such as reproduction, food getting.

COMMUNITY INTERACTIONS

TOLERANCE:The ability to survive and reproduce under a variety of

environmental circumstances. Outside the optimum range causes stress (struggling

to maintain homeostasis).For any environmental factor, going beyond the upper

or lower limit can lead to death.

HABITAT

• The general place where an organism lives

• Organisms will live where they can tolerate (or handle) the conditions

NICHE

• What an organism does in its habitat, how it interacts with its environment, and how it contributes to an ecosystem

• Example: “The red fox's habitat might include forest edges, meadows and the bank of a river. The niche of the red fox is that of a predator which feeds on the small mammals, amphibians, insects, and fruit found in this habitat. Red foxes are active at night. They provide blood for blackflies and mosquitoes, and are host to numerous diseases. The scraps left behind after a fox's meal provide food for many small scavengers and decomposers.”

• Make a list of things in your niche

COMPETITION

• When organisms attempt to use the same resource, competition occurs• Example: the roots of

different plants compete for water, nutrients, and space in the soil

COMPETITION

• Occurs when:• Organisms attemp to use the same limited ecological

niche in the same place at the same time.

• Competitive Exclusion Principle• No two species can occupy exactly the same niche in

exactly the same habitat at exactly the same time.

TYPES OF COMPETITION

• Intraspecific- competition between members of the same species

• Interspecific- competition between members of different species.

THE COMPETITIVE EXCLUSION PRINCIPLE:

• The idea that no two species can occupy exactly the same niche, in the same habitat, at the same time

• If two species try to do this, one of three things can happen:• 1 species will compete better for the niche and the other

species will die out • 1 species will compete better for the niche and the other

species will move away• The two species will split or share the niche. Ex:

rainforest lizards that eat the same bugs can occupy different parts of the forest

What is the result if 2 species do attempt to occupy the same niche?

• One species will be better at competing for limited resources and will eventually exclude the other species.

• Instead of competing for similar resources, species usually DIVIDE them.

• Give an example of this:• Three species of N. America warblers all live in the

same trees and eat insects. • But feed on different types of insects in different

sections of the tree. **By causing species to divide resources competition helps determine the number and kinds of species in a community and the niche each species occupies.

PREDATOR-PREY REALTIONSHIPS

• Predation• An interaction in which one animal (the predator)

captures and feeds on another animal (the prey)

• Predators can affect the size of prey populations in a community and determine the places prey can live and feed.

THINK!

Give an example of a predator-prey relationship

that you may see in your own local ecosystem.

Hawks catching & eating rodents

HERBIVORE-PLANT RELATIONSHIPS

• Herbivory• An interaction in which one animal (the herbivore) feeds

on producers (plants)

• Herbivores can affect both the size and distribution of plant populations in a community and determine the places that certain plants can survive and grow.

THINK!

Give an example of Herbivory that you may see in your own

local ecosystem.

Deer eating flowers from a garden

SYMBIOSES

SYMBIOSIS

• Definition:• Any relationship in which 2 species live closely together

• We will discuss 3 main types of symbiotic relationships in nature. • Mutualism• Parasitism• Commensalism

MUTUALISM

• Both species involved

Who benefits?

• No one!

Who is harmed?

• (+/+) Clownfish living with sea anemone

Examples

Symbiotic relationship in which both species benefit from the realtionship

PARASITISM

• The Parasite

Who benefits?

• The Host

Who is harmed?

• (+/-) leech feeding on the blood of a human host

Examples

Symbiotic relationship in which one organism lives inside or on another organism and harms it by obtaining all or part of its nutritional needs from the host organism.

COMMENSALISM

• One of the organisms

Who benefits?

• No One!

Who is harmed?

• (+/0) Barnacles attached to the skin of a grey whale

Examples

Symbiotic relationship in which one organism benefits and the other is neither helped nor harmed.

?

WHAT IS A BIOME?

• Large regions of land that are characterized by a specific type of climate and certain types of plant and animal communities.

• Made up of many individual ecosystems• Vary according to their location from the

equator (latitude)

BIOMES OF THE WORLD

In which biome is Livingston, NJ located?

“Temperate forest”, also called “temperate deciduous forest”