Unit 2A- 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

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- all living things from all biomes on the planet

Where is the biosphere located and what does it include? o 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. o Because there is life nearly everywhere on Earth, the word biosphere is a very broad term and the Earth itself is essentially our biosphere.

Levels of Organization in the Biosphere Increasing Complexity __________________- ________________- Population-__________________- _____________________- Fill in each box with the correct level of organization in the biosphere (the size of the box indicates the broadness of each category). Include a word or two to help you remember what each grouping means.

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.

Abiotic Factors Any nonliving (physical) part of the environment Examples: sunlight, heat, precipitation, humidity, wind, water, soil, etc.

What are the Biotic and Abiotic Factors in this Environment?

Biotic and Abiotic Factors are Closely Linked The mucky shoreline, biotic, abiotic or both? Both! Abiotic- soil, water, sand, etc. Biotic- bacteria, fungi, small animals like worms, etc.

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”

Temperate (Deciduous) Forrest Has both deciduous and coniferous trees Deciduous trees shed leave in autumn Cold winters, warm summers Soils are fertile Some animals hibernate in winter, others migrate to warmer climates, others camouflage in winter when trees are bare

Energy, Producers, and Consumers Energy, Producers, and Consumers

Energy Organisms must get energy in order to function Different organisms get their energy in different ways Almost all energy on Earth starts from the sun!

1. Autotrophs Organisms that capture energy from sunlight or chemicals and turn it into food Also called primary producers

Primary Producers Most commonly use energy from the sun to create sugars and starches (photosynthesis) Important examples: plants, algae, photosynthetic bacteria

Chemosynthesis When primary producers turn the energy in chemicals (like hydrogen sulfide) into carbohydrates. o Mostly bacteria o Found in extreme environments (deep ocean, hot springs, volcanoes)

2. Heterotrophs Eat other organisms for food. Also called consumers

Types of Consumers Classified by the way they acquire energy Carnivores- kill and eat other animals Herbivores- eat plant materials Omnivores- eat both plant and animal materials Scavengers- consume carcasses of organisms that have died or that were killed by predators Decomposers- 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) * Put these definitions in the correct bubbles on pg. 5 in the notes.

Types of Consumers

Food Chains and Food Webs

Energy Flows One Way Almost all energy on Earth starts from the sun! Energy flows through an ecosystem in a one way direction from producers to consumers

Food Chain- a series of steps in which organisms transfer chemical energy by eating and being eaten. (food molecules are chemicals ) Phytoplankton = algae that is floating and not attached to something **Read an arrow as “is eaten by”

Food Webs Food web- a network of complex interactions formed by the feeding relationships among the organisms of an ecosystem AlgaePlants

Decomposers and Detritivores are Important in Food Webs Dead plant and animal material must be broken down so the molecules can be reused for new life Decomposers (bacteria and fungi) are heterotrophs that break down this dead plant and animal material into detritus o This releases nutrients into the soil for new primary producers to grow (“recycles nutrients”) Detritus is eaten by detritivores (like crayfish, grass shrimp, and worms), further releasing nutrients into the soil

Food Web Disturbances Environmental changes can cause changes in a food web Krill

Food Web Disturbances How 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 Levels Each step of a food chain or food web is called a trophic level First trophic level- always primary producers All other trophic levels are occupied by different types of consumers

Ecological Pyramids Illustrations used to show the amounts of energy or matter in each trophic level of a food web Three types of pyramids: energy, biomass, and numbers

Pyramids of Energy Show the amount of energy available at each trophic level Only 10% of the energy in one trophic level is passed to the next level up. The rest of the energy is either used by the organisms to do life processes (like growth, reproduction, respiration, etc.), or released as heat How much of the energy available to the producers is available to the third-level consumers?

Pyramids of Biomass Biomass is the total amount of living tissue in a trophic level Primary Producers will have the greatest biomass o There must be enough producers to provide energy for all of the consumers

Pyramids of Numbers Show the number of individuals at each trophic level If the main producer is a large organism, the base of the numbers pyramid will be small Pyramid of Numbers Grass

Habitat vs. Niche

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.”

Community Interactions

Competition Competition- when organisms attempt to use the same limited ecological resource in the same place at the same time. o Example: the roots of different plants compete for water, nutrients, and space in the soil

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: o 1 species will compete better for the niche and the other species will die out o 1 species will compete better for the niche and the other species will move away o The two species will split or share the niche. Ex: rainforest lizards that eat the same bugs can occupy different parts of the forest

Predator-Prey Relationships 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. Give an example in our ecosystem

Herbivore-Plant Relationships Herbivory : an interaction in which one animal (the herbivore) feeds on producers (such as 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. Give an example in our ecosystem

Graphing Community Interactions What is shown in this graph? Use the graph to answer the two questions below it in the notes.

Keystone Species : a single species that is not usually abundant in a community yet exerts strong control on the structure of a community.

Keystone Species A species whose presence is important for the structure of a community Example: Kelp Sea Urchin Sea Otter Provide shelter and food for other animals Due to hunting What will happen to this community? Sea otters were a keystone species!

Symbioses Any relationship in which two species live closely together is called symbiosis Three main classes of symbiosis: o Mutualism o Parasitism o Commensalism

1. Mutualism A relationship in which both species benefit Example: clown fish live in sea anemones. o Clown fish are protected from predators by hiding inside the stinging anemone o The anemone is protected from being eaten by the clown fish who wants to defend its home

2. Parasitism When one organism lives in or on another organism and harms it by obtaining all or part of its nutritional needs from the host organism. Example: Fleas feed on blood and skin of their hosts; cause discomfort and could transmit disease

3. Commensalism One organism benefits and the other is neither helped nor harmed Example: barnacles (small ocean animals) live on whales. They do not harm the whale but the whale’s swimming allows the barnacles to get constant food particles from the water.

Cycles of Matter

Four Main Elements of Living Things: CHON Make up: o Water o Carbs o Lipids o Nucleic acids o Proteins

Energy & Matter Energy flows in a one way direction starting from the sun (it is not recycled) Matter is recycled through the biosphere

Matter is Recycled Within and Between Ecosystems This is different than the one-way flow of energy through an ecosystem Biogeochemical Cycles- process in which elements, chemical compounds (water and nutrients), and other forms of matter are passed from one organism to another and from one part of the biosphere to another.

Processes in Biogeochemical Cycles can be… Biological- Geological- Chemical- formation of clouds/precipitation Physical- flow of running water Human Activity- Cellular respiration, photosynthesis, decomposition, nitrogen fixation, etc. Erosion, rock formation, heat and pressure from the earth Logging, deforestation, burning fossil fuels, wastes, fertilizers

Energy powers the cycles of matter Matter is transformed, never created or destroyed

The Water Cycle Water moves between oceans, atmosphere, and land Can be inside or outside of organisms

How does water vapor enter the atmosphere? Evaporation Transpiration Combustion Respiration

Once water vapor is in the atmosphere… Condensation Precipitation Runoff Groundwater Also use evaporation

Nutrient Cycles The cycling of carbon, nitrogen, and phosphorus through organisms and the environment are especially important

The Carbon Cycle Carbon is a major component of all organic compounds. found in some inorganic compounds Example: calcium carbonate (CaCO 3 ) – molecule that is part of animal skeletons Example: carbon dioxide (CO 2 ) - major part of the atmosphere and necessary for photosynthesis.

Carbon & Oxygen Oxygen often cycles with carbon through the biosphere, particularly due to photosynthesis and cellular respiration.

Makes Cell Walls

Fossil Fuels Fossil Fuels : Energy rich fuels ( coal, oil, and natural gas ) created from carbon-containing compounds of ancient, dead forests, marine organisms, or other animals have been buried and transformed by pressure and heat.

Major reservoirs (locations of large amounts) of carbon in the biosphere include the: o Atmosphere o Oceans o Rocks o Fossil Fuels o Forests

Questions Use your knowledge and the carbon cycle diagram in the notes packet to complete the questions on pg. 16 of the notes.

bromothymol blue 3:20

The Nitrogen Cycle Nitrogen is required to make amino acids and nucleic acids

Forms of Nitrogen Different forms of nitrogen occur naturally in the biosphere. Nitrogen gas (N 2 )makes up 78% of earth’s atmosphere. Ammonia (NH 3 ), nitrate ions (NO 3 - ), nitrite ions (NO 2 - ) are 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

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. They “change” (=fix) the nitrogen into usable forms The usable forms can then be used by other organisms Thus, nitrogen-fixing bacteria are an essential part of the nitrogen cycle.

Nitrogen Fixation : The conversion of Nitrogen Gas (not usable) into Ammonia, Nitrates, and Nitrites (usable) by bacteria. Some of these bacteria live in the soil whereas others live on the roots of certain plants called legumes (ex. peanuts, peas, soybeans). Bacteria are the driving force of the nitrogen cycle!

Once these forms of nitrogen are available, primary producers can use them to make proteins and nucleic acids. Consumers eat the producers and reuse nitrogen to make their own nitrogen-containing compounds (and so on through the food web).

Answer the questions on pg. 18 of the notes packet

Fertilizers Contain Nitrogen & Phosphorus Eutrophication: excess growth of algae due to increased levels of fertilizers in the water. o Creates an algal bloom o Algae takes oxygen from other organisms and may release toxins