Notes: Biology I S409 – Ecology Unit Chapter 2 – Principles of Ecology 2.1 – Organisms & Their Relationships 2.2 – Flow of Energy in an Ecosystem 2.3 – Cycling of Matter Chapter 5 – Biodiversity & Conservation 5.3 – Conserving Biodiversity

2.1: Organisms & Their Relationships definition: the scientific discipline in which the relationships among living organisms and the interaction the organism have with their environments are studied. The study of organisms interacting with each other & the environment

T: 2, 9 The Biosphere Biosphere: the portion of the Earth that supports life (polar, desert, ocean & rainforest) Biotic Factors: factors in an organisms environment The biological influences on organisms within an ecosystem Examples: animals, plants, mushrooms & bacteria Abiotic Factors: factors in an organism’s environment Physical, or nonliving, factors that shape ecosystems Examples: temperature, air/water current, sunlight, precipitation, humidity, soil nutrients

Understanding Communities Keys to understanding biological communities is to be aware of latitude and climatic conditions - the average conditions in a region Temperature - # of hours/intensity of sunlight Precipitation - amount of moisture Topography – shape & elevation of landmasses (mountain affect) – the condition of the atmosphere at a specific place and time

Levels of Organization Ecologists that occur between the levels of organization… Organism: one individual living thing Species: organism that produces offspring Population: several of same species in one place Community: populations interacting; different species Ecosystem: communities interacting w/ environment Biome: large geographic area; different ecosystems w/ similar climate and communities Biosphere: combines all parts of the planet: land, water, & air that support life The portion of the planet that supports life

Levels of Organization

Ecosystem Interactions Habitat: an area where an organism lives Niche: role or position that an organism has in its environment Community Interactions Competition: organisms of the same or different species attempt to use the same ecological resource in the same place at the same time. Predation: interaction in which one organism captures (predator) and feeds on another organism (prey)

Symbiotic Relationships Symbiosis: a close relationship between 2 species Mutualism: both species benefit from the relationship; Ex: bees & flowers Commensalism: one member of the association benefits and the other is neither helped nor harmed; Ex: shark & remora fish Parasitism: one organism lives on or inside another organism and harms it. The parasite obtains all or part of its nutritional needs from the other organism, called the host. Ex: hookworm, tick

2.2: Flow of Energy in an Ecosystem All living things require energy… where does it come from? Originally = the sun Stored form = chemical bonds Organisms differ in how they obtain their energy: troph: an organism that makes its own food troph: an organism that gets its energy by consuming other organisms

Energy in an Ecosystem T: 1, 5 Autotrophs: Capture energy from the environment to make/produce own food AKA (Example: Green Plants) Two ways to produce own food Using the sun: Photosynthesis Using inorganic chemicals: Chemosynthesis NO sun Ex: Hydrogen Sulfide

Energy in an Ecosystem Heterotrophs: rely on other organisms for food AKA consumers; can NOT make own food Herbivores Eat plants only; Cow; 1st order consumer Carnivores Eat animals only; Snake; 2nd order consumer (or 3rd?) Omnivores Eat both plants & animals; Bear; 3rd order consumers Detritivores Engulf dead plant & animals; Worm, snail, mite Decomposers Absorb nutrients from dead organisms; Fungus (mushroom), bacteria

Concept Check No matter how complicated a food web can get, what is the original source of energy? What are two new names for plants? What are two names for organisms that can NOT make their own food?

T: 6 Models of Energy Flow Energy passes from source to organism to organism to organism etc. This sequence is called a Food Chain Sun, wheat, mouse, snake, hawk Each link in a food chain (which is a transfer of energy) is called a Trophic Level First trophic level is always a producer 1st, 2nd, 3rd, & 4th trophic levels are consumers When Food Chains cross or interact it becomes a… Food Web: a model of the relationships that form a network of interactions (producer to decomposer)

Models of Energy Flow… T: 6

T: 6 Food Web Examples

Ecological Pyramids T: 7 Ecological Pyramids: diagrams relationships (3 types) Pyramid of Energy: each level represents the amount of energy available to that trophic level Only 10% of energy can be passed; less energy available at each successive level or with each step up, there is an energy loss of 90% Pyramid of Biomass: total amount of living tissue w/in a given trophic level; biomass decreases at each successive level or each level represents the amount of biomass consumed by the level above it Pyramid of Numbers: diagrams # of individuals in each level; #’s decrease at each successive level

2.3 Cycling of Matter Energy flow is matter is NOT used up! Matter can be through ecosystems Important Biogeochemical Cycles Water: repeated movement of water b/w Earth’s surface & the atmosphere Carbon & Oxygen: photosynthesis, burning of fossil fuels, decomposition of plants & animals Nitrogen: soil nitrogen fixed by bacteria for use by organisms; atmosphere is ~80% nitrogen Phosphorus: cycles among the land, ocean sediments, and living organisms

3 Main Ways to Study Ecology Asking questions Making hypotheses Usually leads to experimenting & modeling Test hypotheses Set up in a lab or in the field Used when time &/or size is too large Mathematical formulas based on above used to make predictions, which are further tested

Concept Check What is ecology? What is the most simple group of more than one kind of organism in our biosphere? What are 3 methods ecologists use to study the living world?

5.3 – Conserving Biodiversity Notes: Biology I S409 – Ecology Unit Chapter 5 – Biodiversity & Conservation 5.3 – Conserving Biodiversity

5.3 Natural Resources The biosphere currently supplies the basic needs for more than 6 billion humans in the form of natural resources The consumption rate of natural resources is evenly distributed The natural resource consumption rate is much higher for people living in developed countries than for those people in developing countries Because of the rising human population growth and an increased rate of consumption of natural resources a long-term plan for the use and conservation of natural resources is important

T: 12 Human Impact Human activities - most important source for environmental change on Earth that affect the Biosphere Hunting & Gathering: food & sport Subsistence Hunting (hunt for food) Agriculture: farming plants & animals Monoculture: one type of crop in an area Green Revolution: use of chemical fertilizers Problems w/ pesticides (water) and resistance  Urban Development: Use of fossil fuel for energy Production of waste

Renewable vs. Nonrenewable Resources Renewable resources: those resources that are replaced by natural processes faster than they are consumed can regenerate if they are alive can be replenished by biochemical cycles if nonliving Ex: Agriculture, Animals, Trees, Water, Solar energy NOTE: A resource may be destroyed or polluted and will no longer be useable!! A renewable resource is not necessarily unlimited! Nonrenewable resources: those sources that are found on Earth in limited amounts or those that are replaced by natural processes over extremely long periods of time Ex: fossil fuels, mineral deposits, coal, oil, & natural gas and an extinct species (or cleared forests?) 

Use of Natural Resources Sustainable use: using natural resources at a rate in which they can be replaced or recycled while preserving the long-term environmental health of the biosphere Conservation of resources include: Reducing the amount of resources that are consumed Recycling resources that can be recycled Preserving ecosystems Using the ecosystem in a responsible manner Ex: Forest Management, Aquacultures Pollutant: a harmful material that can enter the biosphere through the land, air, or water The contamination of air, water, or soil by materials released into the environment through human activities.

Comprehension Check Can you name one type of renewable resource? Can you name one type of nonrenewable resource? What effects do sustainable-use have on the environment?

Protecting Biodiversity Protected areas in the US 1st National Park: Yellowstone National Park (1872) Since, added many national parks and nature reserves International protected areas 7% of the world’s land is in some type of reserve The United Nations supports Biosphere Reserves and World Heritage Sites This includes megareserves which have habitat areas that are protected from human activity by “buffer zones” which sustainable use of natural resources is permitted

Protecting Biodiversity Biodiversity Hot Spots: An area where there are high levels of endemic species (a species only found in one specific location) There must be at least 1500 species of vascular plants that are endemic The region must have lost at least 70% of its original habitat Currently 34 hot spots on the Earth.

Corridors between habitat fragments Corridors: passageways between habitat fragments Positives: All organisms from one area to move safely to the other Creates a larger piece of land that can sustain a wider variety of species and a wider variety of genetic variation Negatives: Disease can also easily pass Increases edge effect

Restoring Ecosystems T: 15 Sometimes biodiversity is destroyed in an area such that is no longer provides the abiotic and biotic factors needed for a healthy ecosystem Cleared rainforest, mining, oil spill Bioremediation- use of living organisms to detoxify a polluted area (microorganisms in soil to break down toxins) Biological Augmentation- adding natural predators to a degraded ecosystem (introducing ladybugs to eat aphids; which destroy crops)

Legally Protecting Biodiversity The 1970’s there was a lot of attention given to issues surrounding the environment 1973: The US enacted the Endangered Species Act 1975: International Treaty formed CITES The Convention on International Trade in Endangered Species of Wild Fauna and Flora

Comprehension Check What makes something a Biodiversity Hotspot? How many Hotspots currently exist on Earth? What are some things that can be done to protect biodiversity?