AGENDA May 12 Big Question: How does energy flow through an ecosystem? 1. Vertebrates QUIZ – 30 Minutes 2. Intro to Chapter 3 Ecology 3. Ecology Project Requirements and Rubric 4. Homework and Closing thoughts Ecology Projects DUE DATE – Tuesday May 19

Chapter 3: The Biosphere

What is Ecology? The study of the interactions of organisms with one another and with their physical surroundings. What are some of these interactions? Where an organism lives What it eats Its impact on other living things

Life on Earth The Biosphere is the part of Earth where life exists. It includes all of the land, air, and water on the planet. It also includes all of the life within it.

What does an ecologist study? The study of ecology includes… the environment in which an organism lives the interactions of organisms with one another the interactions of organisms with the non-living environment.

Ecosystems What is an Ecosystems? An areas consisting of all physical features and living organisms. Abiotic factors – physical features Water, sunlight, rocks, soil, rainfall Biotic factors – all living things Plant life, Animal life

AGENDA May 13 Objective: Describe the flow of energy through an ecosystem. 1. Trophic Levels and Energy 2. Biogeochemical Cycles 3. Homework and Closing thoughts Chapter Worksheets

Distribution of Life Is all life on Earth evenly distributed throughout the planet? The answer is no. Explain why this is the case.

Section 4: The Flow of Energy One of the most important factors in any ecosystem. What is the ultimate source of energy for all living things? The Sun How much of the sun’s energy that reaches the Earth is actually used by living things? Approximately 0.1% worldwide

Energy Flow and Use Plants absorb energy from the sun. How do plants use this energy? Animals in turn eat plants to obtain this energy. Animals store even smaller amounts of energy.

Vocabulary Check Define the following terms… Producer Consumer Provide an example Consumer

How do organisms get energy? Producers make their own food using the sun Consumers obtain their energy either directly or indirectly from producers. Primary consumers feed directly on producers (herbivores)

How do organisms get energy? Secondary consumers are consumers that feed on primary consumers. Carnivores make up the second level, third level, and fourth level of consumers. For example, a tertiary (third level) consumer feeds on a secondary consumer. Snake Frog Insect Plant

How do organisms get energy? Energy flows through an ecosystem from the sun to producers to consumers. When animals and plants die, decomposers break down this non-living organic matter to obtain their energy. Bacteria and fungi are examples.

Energy Pyramids Recall that energy cannot be created or destroyed. Because some energy is lost as heat, about 10% of the energy taken in by a trophic level is available for consumption by the next trophic level. This energy is transferred at each level and is stored in the tissues of those organisms.

The Flow of Energy

Biogeochemical Cycles Is energy recycled in an ecosystem? No, energy only moves in one direction through an ecosystem. What does this mean? Energy moves from the sun, to producer, to consumer. Energy cannot move in the opposite direction.

Biogeochemical Cycles How do we get the nutrients we need to survive? Food we eat We get these essential nutrients from the food we eat. All organisms require specific essential nutrients in order to grow. Name some essential nutrients that plants need. Water, carbon dioxide, phosphorus, potassium, etc

Biogeochemical Cycles Nutrients can be reused over and over again within an ecosystem. They move through the biosphere in a series of physical and biological processes called Biogeochemical Cycles.

The Four Biogeochemical Cycles What are the four cycles essential for an ecosystem? Water, Nitrogen, Carbon, and Oxygen The Water Cycle Movement of water from the atmosphere to Earth and back to the atmosphere. Evaporation and Condensation Groundwater, Water Table

The Nitrogen Cycle Why do organisms need Nitrogen To build Proteins 78% of atmosphere is free nitrogen. Also present in wastes produced by many organisms and in dead or decaying matter. Nitrogen fixation – Changing of free nitrogen into nitrogen compounds such as nitrates or nitrites that can be used by living things. Performed by certain types of nitrifying bacteria that live on the roots of plants such as legumes (beans, peas, peanuts).

The Nitrogen Cycle Nitrogen fixation  Usable by Plants  Stored as Plant Proteins  Animals eat plants  Make Animal Proteins  Nitrogen compounds return to soil when animals/plant die  Denitrification returns free nitrogen to atmosphere. Denitrification – denitrifying bacteria break down nitrogen compounds back into free nitrogen which returns to atmosphere.

Nitrogen Cycle

The Carbon Cycle The movement of carbon through the environment relies upon plants and animals. Photosynthesis – Producers use carbon dioxide to make glucose. Respiration – Consumers use glucose to add carbon dioxide back into atmosphere

The Oxygen Cycle Water molecules split during Photosynthesis release Oxygen into air. Oxygen is used during respiration. Water is released during respiration which is absorbed by plants to renew the cycle.

Limiting Factors A organism’s ability to capture energy and use it to grow new tissue is controlled by several factors. Nutrients are limiting factors which affect this ability. Disturbing the natural balance of nutrients can sometimes be very harmful to an ecosystem. Fertilizers and pollution can cause growths and blooms of algae or bacteria. Dianchi Lake, China

Feeding Relationships A Food Chain is the simplest relationship of plants and animals relying on one another for food. Food webs are more complicated but take into account all of the connections between plants and animals in an ecosystem.

Food Web