The Biosphere

Ecology the scientific study of interactions among organisms and between organisms and their environment Plant Biome Ecosystem Community Population Species Biome: a group of ecosystems that share similar climates and typical organisms Ecosystem: All organisms that live in a place together within their environment - abiotic factors interacting with biotic factors Community: Different populations that live together in a defined area - forest plants, animals, and fungus interacting Population: individuals that belong to the same species and live in the same area - a group of Bison living in the same area Species: similar organisms that can breed and produce fertile offspring

Environmental Factors biotic factors: any living part of the ecosystem in which organisms can interact Example: Bullfrog tadpole→ eats algae bullfrog→ insects Other species competing with the bullfrog for food abiotic factors: physical components of an ecosystem (environment) Examples: sunlight, tornados, wind

Energy Consumption: Producers Organisms need energy to carry out daily functions→ metabolism, reproduction, growth They cannot produce energy; they need to get it from other sources Autotrophs (producers): organisms that can convert energy from the sun into useable energy Example: bacteria, algae, plants Primary producers are essential to life on Earth because they produce the essential energy for other living organisms

Photosynthesis: capturing light energy to transform carbon dioxide and water into oxygen energy-rich carbohydrates (sugars) Equation: light + CO2 + H2O → C6H12O6 +O2 Without photosynthesis, there would not be enough oxygen to breathe Chemosynthesis: taking in carbon dioxide, hydrogen sulfide, and oxygen to produce carbohydrates (sugars) and sulfur Chemosynthetic organisms live in harsh environments deepest part of the ocean deep-sea volcanic vents hot springs

Energy Consumption: Consumers Heterotrophs (consumers): organisms that have to aquire energy from other organisms through ingestion Example: birds, cheetah, snakes 6 Types of Consumers Carnivores: kill and eat other animals Examples: tiger, alligator, Scavengers: animals who eat other dead animals that have already been killed Example: vulture Decomposers: feed by chemically breaking down organic matter Examples: bacteria, fungi

Energy Consumption: Consumers 4. Herbivores: organisms that obtain energy through eating plants Examples: cows, caterpillars 5. Omnivores: organisms who eat both animals and plants Examples: Humans, pigs 6. Detritivores: feed on detritus (waste or debris) material Examples: snails, shrimp The categories are in place but they do not always remain 100% -- extrenuating circumstances may push an organism to obtain energy any way they can

Energy Flow: Food Chains/Webs Energy flow through an ecosystem is one-way food chain: series of steps in wihch organisms transfer energy Food Chain

Energy Flow: Food Chains/Webs food web: a network of feeding interactions Food webs are more complicated than a simple food chain Food chains are found within food webs Are decomposers important? YES! They recycle nutrients to feed the primary producers. Food Web

Trophic Levels/Ecological Pyramids trophic level: each step in a food chain or food web ecological pyramids: shows the relative amount of energy or matter in each trophic level Any energy that is passed on to the next level is stored in the organisms Not all energy moves to the next trophic level→ it is released as heat About 10% moves on to the next level→ divide by 10

Trophic Levels/Ecological Pyramids

Biomass/Numbers Pyramids A pyramid of biomass illustrates the relative amount of living organic matter available at each trophic level A pyramid of numbers shows the relative number of individual organisms at each trophic level As you increase through the pyramid, the biomass and the numbers decrease Biomass decreases because there are less numbers as you travel through the pyramid

Cycles of Matter: The Water Cycle Water continuously moves between the oceans, atmosphere, and land The Water Cycle Water becomes vapor in the process of evaporation transpiration: water evaporating from the leaves of plants As water cools and condenses (condensation), it falls to the Earth in the form of precipitation Groundwater: precipitaiton that is soaked into the ground and taken up by plants Runoff: Precipitation that enters a stream, river, or lakes

Water Cycle

Cycles of Matter: Carbon Cycle Carbon is a major component in all organic compunds, such as carbohydrates, lipids, and proteins Coal, oil, and natural gas are referred to as fossil fuels because they are fossilized carbon The Cycle Plants take in CO2 during photosynthesis and convert it to carbohydrates Animals eat the plants and absorb the carbohydrates Animals exhail CO2 back into the atmosphere When animals die, they are decomposed and the carbohydrates become rocks or fossil fuels

Carbon Cycle

Cycles of Matter: Nitrogen Cycle All organisms required nitrogen to make amino acids→ building blocks of protein Forms of Nitrogen N2→ nitrogen gas makes up 78% of the atmosphere NH3→ ammonia Only certain bacteria can use nitrogen directly (nitrogen fixation) primary producers consume the ammonia, nitrates, or nitrites

The Nitrogen Cycle Bacteria turns nitrogen into ammonia, nitrites, or nitrates Primary producers consume the nitrogen and make proteins Consumers eat the plants, which makes nitrogen compounds Decomposers break down the nitrogen in dead consumers Humans add nitrogen to the atmosphere through fertilizers Small amounts of nitrogen are converted into usable forms by lightning

Nitrogen Cycle

Cycles of Matter: Phosphorus Cycle Phosphorous is essential because it is a part of DNA and RNA It is NOT abundant in the atmosphere The Phosphorous Cycle Phosphates are released when rocks and sediments are worn down Plants bind the phosphates when they take it up through the roots It moves through the food web from producers to consumers Other phosphates wash into the river where it dissolves

Phosphorous Cycle