By: Kendra Sanchez SC.912.L.17.9

Trophic Levels What are trophic levels? -Trophic levels are the feeding position in a food chain such as primary producers, herbivore, primary carnivore, etc. Green plants form the first trophic level, the producers. Herbivores form the second trophic level, while carnivores form the third and even the fourth trophic levels. The first trophic level is the producers, followed by the primary consumers, followed by the secondary, and finally, tertiary consumers. On the side of most energy- flow pyramids are the decomposers.

Energy, Producers & Consumers Autotrophs store energy in forms that make it available to other organisms that eat them. That’s why autotrophs are also called primary producers. Carnivores kill and eat other animals. Herbivores eat plant leaves, roots, seeds, grass ect. Omnivores are animals whose diets naturally include a variety of different food that usually include both plants and animals.

Energy in Food Pyramid - There is less available energy in the fourth trophic level because of the loss of energy through metabolism in each of the lower trophic levels. Each successive trophic level contains about 10% of the available energy from the previous trophic level. The other 90% is lost as heat to the atmosphere through metabolism by the organisms in that level.

Producers gather energy from the sun and convert it to useable molecules for consumers. Removing producers from any food chain or web will cause an immediate decrease in available energy.

Biogeochemical Cycles Biogeochemical cycles: the movement (or cycling) of matter through a system. by matter we mean: elements (carbon, nitrogen, oxygen) or molecules (water) so the movement of matter (for example carbon) between these parts of the system is, practically speaking, a biogeochemical cycle.

Biogeochemical Cycles Biological processes: Consists of any and all activities performed by living organisms. These processes include eating, breathing, “burning” food, and eliminating waste products. Geological Processes: include volcanic eruptions, the formation and breakdown of rock, and major movements of matter within and below the surface of the Earth. Chemical and Physical Processes: include formation of clouds and precipitation, the flow of running water, and the action of lighting. Human Activity: Some human activities affect cycles of matter on a global scale include the mining and burning of fossil fuels, the burning of forests, and the manufacture and use so fertilizers.

Carbon Cycle Carbon is such a key ingredient of living tissue and ecosystems that life on Earth is often described as “carbon-based life”. Carbon in the form calcium carbonate is an essential component of many different kinds of animal skeletons and is also found I several kinds of rocks. Carbon and oxygen form carbon dioxide gas, which is an important component of the atmosphere and is dissolved into oceans.

Water cycle Water continously moves between the oceans, the atmosphere, and land, sometimes outside living organisms and sometimes inside them. Water vapor may be transported by winds over great distances. If the air carrying it cools, water vapor condences into tiny droplets that form clouds. When the droplets become large enough, they fall to Earth’s surface as precipitation in the form of rain, snow, sleet, or hail. On land, some precipotitation flows along the surface in what is called a runoff, until it enters a river or stream that carries it to the ocean or lake. Precipitation can also be absorbed by soil and be called ground water.

Summarized In my presentation I described the energy pathways in different trophic levels of food. Biogeochemical cycles Producers, Consumers, Decomposers Water Cycle Carbon Cycle