Biogeochemical Cycles Day 23 Biogeochemical Cycles

THE GENERAL NUTRIENT CYCLE Source: Coronel et. al. (2006). Exploring and Protecting Our World 6. Quezon City: Vibal Publishing House, Inc. p. 107.

What do plants need to make food? Where do plants get water? carbon dioxide? sunlight? Water and carbon dioxide are examples of inorganic nutrients.

NUTRIENTS THAT PRODUCERS NEED Plants make food using nutrients from soil, water, and air. Examples of these nutrients are minerals such as phosphorus and nitrogen (in the form of nitrates, a nitrogen compound) that come from soil, and carbon dioxide which comes from air. These nutrients are called inorganic nutrients because they come from nonliving things.

Some of the foods produced by plants are carbohydrates which contain carbon, hydrogen and oxygen; and proteins which contain nitrogen, carbon, hydrogen and oxygen. Carbohydrates and proteins are examples of organic compounds. Organic compounds come from living things. Nutrients alternate between their inorganic form in the environment and their organic form in living things.

What do decomposers do to the remains of dead organisms?

Decomposers Eventually, people and animals die. Bacteria, fungi and worms feed on the remains of dead organisms. As they do so, they break down the organic compounds and release the nutrients back to the air and soil.

THE CARBON DIOXIDE-OXYGEN CYCLE

Through the process called photosynthesis, plants make food by absorbing carbon dioxide (CO2) in air. Oxygen gas (O2) is released in air as a by-product of photosynthesis. CHEMICAL REACTION: 6CO2 + 12H2O glucose + 6O2 + 6H2O Sunlight energy

glucose + 6O2 + 6H2O 6 CO2 + 12H2O + energy Through the process called cellular respiration, animals (and also plants) use O2 and produce energy and release CO2 in air. CHEMICAL REACTION: glucose + 6O2 + 6H2O 6 CO2 + 12H2O + energy

THE CARBON CYCLE Source: http://www.windows2universe.org/earth/Water/co2_cycle.html

Carbon moves from the air to plants. during photosynthesis “Carbon is part of the ocean, air, rocks, soil and all living things. Carbon doesn’t stay in one place. It is always on the move!” Can you explain again how each movement of carbon happens? Carbon moves from the air to plants. during photosynthesis Carbon moves from plants to animals. when the animals eat the plants Carbon moves from plants and animals to the ground. when plants and animals die and lay to the ground

Carbon moves from living things to the atmosphere. when the living things exhale/respire Carbon moves from fossil fuels to the atmosphere. when fossil fuels are burned Carbon moves from the atmosphere to the oceans. when the carbon soaks into the oceans

Watch these videos of carbon cycle. http://viewpure.com/xFE9o-c_pKg?start=0&end=0 http://viewpure.com/fV2srsG42I4?ref=search

THE NITROGEN CYCLE

Source: http://www.physicalgeography.net/fundamentals/9s.html

What are the four basic processes involved in the Nitrogen Cycle? 1. Nitrogen fixation – nitrogen gas in the air is fixed by the lightning or nitrogen-fixing bacteria in plants into ammonia then organic nitrogen. 2. Mineralization - the organic nitrogen turns into ammonia then ammonium. 3. Nitrification – when nitrifying bacteria or nitrifiers oxidize ammonium into nitrites then into nitrates. 4. Denitrification – when denitrifying bacteria break down nitrates into nitrites then into nitrogen gas back into the atmosphere.

Watch these videos of nitrogen cycle. http://viewpure.com/HOpRT8BRGtk?start=0&end= 0 http://viewpure.com/xfwZV6rtnvw?start=0&e nd=0

CINCH Lesson page Read ‘Cycles of Matter’ lesson page about the Biogeochemical Cycles Refer to CINCH Life Science 6-8 lesson page

ASSIGNMENT: Depending on your class number, research of a credible news (online) article in or about the Philippines that tackles on how certain events and activities disturb the interrelationship in an ecosystem/biosphere. CNs 1- 5  climate change CNs 6-10  muro-ami fishing CNs 11 -15  overpopulation CNs 16-20  illegal logging CNs 21 - 25  kaingin system CNs 26- 30  quarrying CNs 31- 35  natural calamities Read, save that article and take note of the link to your reference.

Adapted from the modules prepared by Ms. Tolosa and Ms. Pe Benito References: Coronel et. al. (2006). Exploring and Protecting Our World 6. The Carbon Cycle http://www.windows.ucar.edu/tour/link=/earth/Water/co2_cycle.html&edu=elem Nitrogen Basics – The Nitrogen Cycle http://nmsp.cals.cornell.edu/publications/factsheets/factsheet2.pdf www.google.com ACKNOWLEDGEMENT Adapted from the modules prepared by Ms. Tolosa and Ms. Pe Benito