Chapter 13 Principles of Ecology

ECOLOGY The study of the interaction among living things and their interactions with their environment

BIOSPHERE Definition- narrow area around Earth’s surface where life can exist. 11 km deep in the oceans to 9 km high in the atmosphere

Limitations to the BIOSPHERE Life requirements- 1. LIQUID WATER- 2. TEMP BETWEEN 10- 40 DEGREES CELCIUS 3. SOURCE OF ENERGY 4. RECYCLING OF NUTRIENTS

ABIOTIC FACTORS- nonliving components of the environment –(example- water, nutrients, pH levels, sunlight and temperature) BIOTIC FACTORS-living components of the environment- (examples- plant life, predators)

Levels of Organization BIOSPHERE- where life on Earth exists BIOME- large regional group of organisms usually characterized by climate conditions and vegetation (desert, tundra, tropical rain forest) ECOSYSTEM- all the abiotic and biotic factors combined (wetlands) COMMUNITY- all the different species that live together POPULATION- only one species in one place at one time (breeding) ORGANISM- an individual living thing

Producer- Defined as an organism that can make its own food Scientific term is AUTOTROPH will literally stands for “self- feeding” Examples are plants, some protists, and some bacteria-

ALL LIFE (99.9%)DEPENDS ON THE SUN PHOTOSYNTHESIS the process of using the suns energy, water, and carbon dioxide to produce Oxygen and the sugar glucose (carbohydrates)

PRODUCERS EXCEPTION- CHEMOSYNTHESIS deep water ecosystems which use energy from deep ocean vents. Bacteria can break down the hydrogen sulfide to make its own energy

CONSUMER Defined as organisms that get their energy by eating other organisms Scientific term is “HETEROTROPH” which literally means “ other feeders” Examples- animals, fungi

CLASSIFICATION based on what consumers eat HERBIVORES- consumer that only eats producers CARNIVORES-consumer that only eats other consumers OMNIVORES- consumer that eats both producers and consumers DETRITIVORES- organisms that feed on dead organic matter DECOMPOSERS-consumer that feeds and breaks down organic matter into simpler compounds

CLASSIFICATION based on what consumers eat SPECIALIST- consumer that primarily eats one specific organism GENERALIST- consumer that have a varying diet

How do consumers get their energy? Use oxygen we breathe to breakdown the sugar glucose This is called CELLULAR RESPIRATION Each cell in our body takes in oxygen and use it to release energy from food

CELLULAR RESPIRATION ALL ORGANISMS USE CELLULAR RESPIRATION TO GET ENERGY FROM FOOD EVEN PRODUCERS USE CELLULAR RESPIRATION ENERGY IS USED FOR GROWTH, CELL REPAIR, MOVEMENT, ETC EXCESS ENERGY IS STORED AS FAT OR SUGAR

ENERGY TRANSFER Each time one organism eats another organism there is an energy transfer Scientists study energy transfer by examining FOOD CHAINS FOOD WEBS TROPHIC LEVELS

FOOD CHAIN (pg 122) Sequence in which energy is transferred from one organism to the next as each organism is eaten

FOOD WEB Many food chains linked together More realistic because most animals eat more than one type of food Shows good interaction in the ecosystem

TROPHIC LEVEL Defined as each step in the energy transfer of a food chain Will rarely have more than 4 consumer levels This is due to energy loss from one level to the next

TROPHIC LEVELS EACH TIME ENERGY IS TRANSFERRED FROM ONE LEVEL TO THE NEXT ENERGY IS LOST AS HEAT AND LESS ENERGY IS AVAILABLE About 90% of energy is used up Only 10% of energy is passed on

ENERGY PYRAMID Shows the relationship of consumers in an ecosystem and how energy is transferred - Each step in the pyramid is a power of ten

BIO MASS Amount of living mass in a trophic level

BIOGEOCHEMICAL CYCLE MOVEMENT OF A CHEMICAL THROUGH THE BIOLOGICAL AND GEOLOGICAL PARTS OF AN ECOSYSTEM

CYCLING OF ELEMENTS Law of Conservation of Mass- the amount of mass in the universe remains constant- therefore the amount of mass of each element in the universe remains constant (exception is radioactive materials)

WATER CYCLE—HYDROLOGIC CYCLE

WATER CYCLE CONDENSATION- the process by which a gas cools and becomes a liquid (formation of clouds) PRECIPITATION-any form of water that falls to Earth’s surface from the clouds (rain, snow, sleet, and hail) EVAPORATION- the change of a substance from a liquid to a gas

WATER CYCLE TRANSPIRATION- process by which plants release water into the air through stomata RESPIRATION- process by which water and carbon dioxide is released into the air from living organisms

CARBON CYCLE All living things are made of carbon Carbon is the key ingredient in fats, proteins, sugars, and nucleic acids Carbon is found in the air and water (Carbon Dioxide) Carbon is also found in the soil naturally as limestone or as the remains of once living organisms- oil, coal, and natural gas

How do humans affect the Carbon cycle? When we burn fuel (oil, coal, gas, wood) we release carbon dioxide into the atmosphere CELLULAR RESPIRATION- gives off CO2 Increased carbon dioxide in atmosphere can lead to global warming

CARBON CYCLE

Global carbon budgeting Pools and fluxes

NITROGEN Organisms need nitrogen to form proteins and nucleic acids Nitrogen makes up 78% of the atmosphere Most organisms cannot use nitrogen as a gas to make proteins

NITROGEN Organisms need nitrogen to form proteins Nitrogen makes up 78% of the atmosphere Most organisms cannot use nitrogen as a gas to make proteins Nitrogen fixing bacteria turns atmospheric nitrogen into usable nitrogen in the soil Decomposers turn waste products and decaying organisms into usable nitrogen

How do we get nitrogen out into a usable form? DECOMPOSERS- break down dead organisms and return nitrogen into the soil in the form of ammonia (NH4). NITROGEN FIXING BACTERIA- found on the roots of plants called LEGUMES (beans, peas, soybeans) turns ATMOSPHERIC nitrogen into usable nitrogen (ammonia).

Many types of bacteria turn the ammonia into nitrates (NO3) all plants can use to make proteins. Animals will get nitrogen from eating the plants or other animals. There are other bacteria that use nitrogen and release it as a gas back into the atmosphere.

How do humans effect the nitrogen cycle? 1. Humans must rotate crops in order to keep the proper amounts of nitrogen in the soil. 2. FERTILIZERS- contain high amounts of nitrogen which is good for the plants but harmful for fish and other organisms when we have nitrogen RUNOFF into the lakes and streams 3. NITROGEN is released into the air when we burn (wood, oil, coal) and can cause the formation ACID RAIN- which is nitric acid

PHOSPHORUS CYCLE Needed to form bones and teeth in animals Phosphate rocks dissolve and release into the soil

PHOSPHORUS CYCLE Needed in the formation of DNA of all cells (PHOSPHATE) PO4 Needed to form bones, teeth, and shells in animals. (PHOSPHATE) PO4

How does phosphorus enter the soil? Phosphate rocks dissolve and release into the soil. Decomposers breaking down waste and decaying organisms release phosphates into the soil. Phosphate is taken in by plant roots and eaten by animals in their diet.

Phosphorus cycle

HOW ECOSYSTEMS CHANGE If a Forest burns down for 80 acres then… 1. What plants would you expect to see first? 2. What animals would you expect to see? 3. What would that area look like in 20 years? What plants and animals?

ECOLOGICAL SUCCESSION Defined as- the gradual change and replacement of types of species in a community Example- first grass would grow- then bushes may grow and kill off small areas of grass then large trees grow and kill off all of the forest floor plant life

Primary Succession Succession that occurs on a surface where no ecosystem existed before Examples- new island formed by a volcano, sand dunes What would you expect to see there?

Secondary Succession Succession on a surface where an ecosystem previously existed Example- forest burning down, chopping down rain forest, flood, volcano, tsunami

PIONEER SPECIES First organisms to colonize a new area- Characteristics of pioneer species 1. fast reproducers- short lifespan 2. produce many offspring 3. have good method of dispersal 4. can remain dormant in rough environment if needed 5. small- and not good competitors

MATURE SPECIES Defined as a species that will eventually dominate an ecosystem if given enough time Characteristics- 1. slow reproducers but long life span 2. produce few offspring but care for young 3. slower dispersal 4. larger and very good competitors

CLIMAX COMMUNITY (page 132) Is the final and stable community when it fully matures