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Ecology

-The study of relationships between living organisms and between organisms and their environment

Species

-A group of organisms that can interbreed and produce fertile offspring

Insects, Plants, Fungi, Marine Invertebrate, Vertebrate

Pools

-Places in which carbon is stored

Soils, Fossil Fuels, Earth's Crust, Oceans, Sediments, Atmosphere, Plants

Fluxes

-Transfer of the element from one pool to another

Reservoir

-

bottom {smallest} to top {biggest}

Population

-A group of organisms of the same species living in the same area at the same time

Community

-A group of populations living and interacting with each other in an area

Ecosystem

-A biological community of interacting organisms and their physical environment

Ex. rainforest, grassland, desert, coral reefs, crop field, aquatic ecosystem

ABIOTIC FACTORS

Definition: non-living chemical and physical parts of the environment

Examples:

1. Sunlight

2. Temperature

3. Precipitation

4. Water or Humidity

5. Soil or Water Chemistry (i.e. Phosphorus and CO2)

6. pH

BIOTIC FACTORS

Definition: all living things in an ecosystem

-organic matter

Examples:

1. Plants

2. Animals

3. Bacteria

4. Fungi

5. Moss

6.Trees

AUTOTROPHS

Definition: Organisms that can produce their own food from the substances available in their surroundings using light (photosynthesis) or chemical energy (chemosynthesis)

-often called "producers"

-produce complex organic compounds --> carbohydrates, fats, and proteins

-make their own energy

Photoautotrophs : perform photosynthesis to convert sunlight into glucose

-converting LIGHT energy to CHEMICAL energy

-water, CO2, energy

i.e. Plants, Algae, Cyanobacteria

Chemotrophs : perform chemosynthesis to convert chemicals into glucose

i.e. some bacteria

HETEROTROPHS

Definition: CANNOT synthesize their own food and rely on other organisms - both plants and animals - for nutrition

-CAN'T make their own energy

-grouped according the way they ingest or eat other organisms

Consumers : Organisms that prey on other organisms

-consume other living organisms or recently living organisms

i.e. herbivores, carnivores, omnivores

Detritivores : heterotrophs that obtain their organic nutrients from detritus

-internal digestion

-feed on detritus or organic waste

-organisms leave behind large quantities of organic material called detritus

-remains of dead decaying bodies also contribute to detritus

-most can be used as a source of energy

-recyclers of energy

Examples: worms, beetles, snails, crabs

Saprotrophs : heterotrophs that obtain their organic nutrients from dead organisms

-external digestion

-referred to as "decomposers"

-interact with their environment at the microscopic level

-feed on decaying or dead plant matter in the presence of adequate levels of water, oxygen, pH, temperature

Examples: some bacteria, mold, mushrooms

Decomposers : obtain nutrients from dead organisms

i.e. Detritivores, Saprotrophs

CONSUMERS

Definition : Organisms that prey on other organisms because they DO NOT have ability to produce their own energy

Primary Consumers ==> herbivores feeding on plants

Examples: rabbits, bears, giraffes, flies, humans, cows

Secondary Consumers ==> carnivores who prey on other animals

Examples: frogs, snakes,

Tertiary Consumers ==> carnivores and omnivores

Examples: hawk, alligator, polar bear

Decomposers ==> organisms that break down dead or decaying organisms

Examples: bacteria and fungi

NUTRIENTS

Definition: chemical substance found in foods that is used in the human body

-refers to the material required by an organism

-supply of inorganic nutrients on Earth is finite

-chemical elements can be endlessly recycled

-energy CANNOT be recycled

Nutrients and Living Systems:

1. plants take nutrients from the soil

2. primary consumer eats the plant and obtains the nutrients

secondary consumers get nutrients from the primary consumer

Flow of Nutrients between abiotic and biotic factors

-organisms absorb the elements they require from abiotic environment, use them, then return them to the environment with atoms unchanged

-passes from one organism to the next before it is released back into abiotic environment

Common Nutrients Needed

1. Carbohydrates

2. Proteins

3. Lipids

4 Vitamins

5. Water

6. Minerals

Sustainable Ecosystem

Definition:

requirements:

Nutrient availability

Detoxification of waste products / Recycling of wastes

Energy availability

MESOCOSM

Definition: enclosed environments that allow a small part of a natural environment to be observed under controlled conditions

ENERGY FLOW

Light energy converted to chemical energy

-producers absorb sunlight

-uses chlorophyll and other photosynthetic pigments

-converts light energy in to chemical energy

-loses an electron and undergoes an oxidation reaction

List three reasons why living organisms need energy for cell activities.

Synthesizing large molecules (like DNA and proteins)

Pumping molecules or ions across membranes by active transport

Moving things around inside the cell, such as chromosomes or vesicles

State how energy in carbon compounds enters most biological communities

-It will originally have been harvested by photosynthesis in producers ; rely on a supply of energy from sunlight

FOOD CHAINS

-linear sequence of organisms

-nutrients and energy are passed on as one organism eats another

-each organisms occupies a different trophic level

-defined by how many energy transfers separate it from the basic input of the chain

Example: Grass --> Cow--> Human

FOOD WEB

-a graph that shows all trophic---eating related interactions between various species in an ecosystem

-arrows point from an organism that is eaten to the organism that eats it

-some species can eat organisms from more than one trophic level

TROPHIC LEVEL

Definition: the position an organism occupies within a feeding sequence

-Unit : per square metre

Trophic Level 1 ==> Producer

Trophic Level 2 ==> Primary Consumer

Trophic Level 3 ==> Secondary Consumer

Trophic Level 4 ==> Tertiary Consumer

-average amount of energy passed through each trophic level --> 10%

Energy Decreasing at Higher Trophic Levels

Most energy in food that's digested and absorbed by organisms is released by them in respiration for use in cell activities

Organisms in trophic level aren't usually entirely consumed in the next trophic level

Not all parts of food ingested by these organisms are digested and absorbed

-energy transfer between trophic levels is inefficient --typical efficiency of 10%

this limits the length of food chains

CARBON CYCLE

Definition:

Role of Photosynthesis

1. Plants use CO2 from the air to make sugars

2. Most living things get the carbon they need by eating plants

3.Autotrophs absorb carbon dioxide from the atmosphere→ convert it into carbohydrates, lipids, and other carbon compounds

4.This has the effect of reducing the carbon dioxide concentration of the atmosphere

CO2 to Hydrogen Carbonate Ion in Water

-CO2 dissolves in water

-some remain as dissolved gas

-remainder will combine with water to form Carbonic Acid (CO2 + H2O -->H2CO3)

-CO2 is soluble in water

-carbonic acid can dissociate to form hydrogen + hydrogen carbonate ions

H+ and H2CO3

-dissolved CO2 and hydrogen carbonate are absorbed by aquatic plants / other autotrophs living in water

-uses them to make carbohydrates and other carbon compounds

Seven Flux Processes

Photosynthesis – removes carbon dioxide from the atmosphere and fixes it in producers as organic compounds

Respiration – releases carbon dioxide into the atmosphere when organic compounds are digested in living organisms

Decomposition – releases carbon products into the air or sediment when organic matter is recycled after death of an organism

Gaseous dissolution – the exchange of carbon gases between the ocean and atmosphere

Lithification – the compaction of carbon-containing sediments into fossils and rocks within the Earth’s crust (e.g. limestone)

Combustion – releases carbon gases when organic hydrocarbons (coal, oil and gas) are burned as a fuel source

-Unit of Carbon Flux --> Gigatonnes

- Pool + Fluxes = Global Carbon Cycle

PEAT AND COAL

Peat : partially decomposed matter that has been compressed to form dark brown acidic material

Coal:

Formation of Peat

Formation of Coal

GREENHOUSE GASES

-most impactful --- CO2 and Water Vapour

act like an insulating layer

-Earth is a closed system

-NOT much

-CO2 and Water Vapour are recycled

-CO2 -- released by hetero and autotrophs when they respire and tough the burning of biomass

two forms of recycling -- photosynthesis + dissolving in oceans and lakes

-water vapour--gaseous form of water, evaporation from bodies of water, natural precipitation

.e. rain, hail, snow return water to earth

-NEEDS to be able to abosrb longer waelength radiations

-Methane + Notrous Oxides are capable of absorbing loner waelength

-

Examples:

Carbon Dioxide (CO2)

Methane (CH4)

Nitrous Oxide (N2O)

Water Vapor (H2O)

Ozone (O3)

Variable that Determines the Concentration of a Gas in the Atmosphere

1. Ability to absorb longwave radiation

Gases that have a greater capacity to absorb longwave radiation will have a greater warming impact (per molecule)

2. Concentration Within the Atmosphere

The greater the concentration of a gas, the greater its warming impact will be within the atmosphere

The concentration of a gas will be determined by both its rate of release and persistence within the atmosphere

Impact of Atmospheric Methane VS CO2

Mechanism by which Greenhouse GAses Trap Heat in the Atmosphere

Sources of CO2 and Water Vapor in the Atmosphere

Electromagnetic radiation at most wavelengths from the Sun passes through the Earth’s atmosphere.

The Earth absorbs electromagnetic radiation with short wavelengths and so warms up. Heat is radiated from the Earth as longer wavelength infrared radiation.

Some of this infrared radiation is absorbed by greenhouse gases in the atmosphere.

The atmosphere warms up

CARBON DIOXIDE and the CORAL REEFS

-massive amount of CO2 dissolved into the oceans

-causes the average pH to drop

-lowering pH ==> increases the solubility of calcium carbonate, lowering the amount that is available

-less CaCO3 ==> slow the building of coral reefs and make the more brittle, exoskeletons begin to dissolve

-increasing concentrations of dissolved CO2 leads to ocean acidification

-negative impact on the ability of corals to develop

-less capable of recovering from damage

-calcium carbonate --> ed by corals to build their exoskeletons ; process known as calcification