Sequence | Background | Objectives | Materials | Activity | Extensions | Evaluations

TOPIC-TITLE Marine & Aquatic Habitats Activities - How about a Little Give and Take? AUTHOR Eileen Gray Ann Alexander Tina Darling Nelda Sharkey GRADE SUITABILITY Middle School SCOPE Chemical and Biological Oceanography

Sequence Photosynthesis and respiration, including the overall chemical reactions and organisms involved in these processes, will be introduced. Discussion will include how organisms impact one another and use the abiotic elements such as phosphates, nitrates, carbonates, carbon dioxide, and oxygen. Interactions between marine and terrestrial systems will also be discussed. (Be sure to include coral reefs.) < < go top

Background Summary Abiotic, or non-living, factors of a marine or aquatic ecosystem may include nutrients such as nitrogen and phosphorus, dissolved oxygen, and carbon dioxide. Unbalanced systems include only plants, such as algae, or animals. Balanced systems include both plant and animal components. Balanced ecosystems require equilibrium between reactions of photosynthesis and respiration. Interactions between the various components of a balanced system are examples of biotic factors. < < go top Objectives Students will be able to do the following: Design a closed system to test the relationships between plants and animals. Use a chemical test kit to monitor abiotic fluctuations within this living system. Observe how living organisms respond to fluctuations in abiotic factors. < < go top Materials Quart or gallon jars (all same size, preferably with lids) Algae and/or aquatic plant Fish or water snail Phosphorus and nitrogen fertilizer and an analytical balance (if solid fertilizer is used) Sand or gravel Unchlorinated, aged water (stream, lake, or estuarine water or stabilized aquarium water) Graduated cylinder Bromothymol blue Hach or LaMotte test kit (nitrate, phosphate, dissolved oxygen, pH) Thermometer < < go top Activity The tasks of the cooperative learning groups will be to design a closed system and research and discuss the viability of such a system using the scientific method of inquiry. In a 10-14 day period students will do the following: Monitor, observe, and record in a journal fluctuations of one biotic factor. Monitor, observe, and record in a journal changes of one abiotic factor. Measure and record initial and final levels of abiotic factors. Illustrate the research and results by sketching and labeling the setup (control and experimental). Design and use a chart to record daily observations. < < go top Possible Extension Investigate and discuss the design of the Biosphere Project. Investigate and discuss the requirements and design of a space station. Investigate and discuss the requirements and design of a long-term underwater habitat. Investigate and discuss the requirements and design of futuristic, closed-domed cities. Investigate and discuss the requirements and design of aquaculture. < < go top Teacher Evaluation Were objectives accomplished? Did students stay on task and work cooperatively? (Students should work in cooperative teams.) System setup and testing procedure. Journal of events. < < go top