|
|
Earthworks
Earth System Science for Secondary Teachers
How has air pollution affected the biodiversity of environmental indicator organisms such as lichens and the invertebrates that depend on them? (2003)
Grade level: 6-8
Content Area:
Time: 2 weeks
Standards/(TAKS):
- Using safe, environmentally appropriate practices in field investigations
- Use scientific methods in field investigations
- Identify components of ecosystems
- Identify components to which organisms respond
- How different environments support different varieties of organisms
- Matter/energy interactions in food chains
- How organisms maintain stable internal conditions in changing environments
Background knowledge/skills:
Safety/ethics in field studies, measurement, variables, field notes, use of grid, sampling, use of microscope, simple tree ID, air pollution, GPS, lichens
Objectives:
- Students will conduct an ecology field investigation to determine #'s and kinds of lichens and invertebrates on lichens on our campus.
- Students will research what lichens were present in the past and how they may have changed (arboretum/museum of nat. sci.)
- Students will research annual ozone values to determine levels of air pollution in Houston (TNRCC web site, EPA website)
- Students will share data on lichens and invertebrates with students using same protocols in a less impacted environment (Connecticut)
Materials: GPS, string, metric tape measure, meter sticks, acetate, 100 circle grids, vis-a-vi markers, tape, lichen guide books, microscopes, Petri dishes, cork borer
Procedures:
Introduce problem: We have been hired as ecologists to help TNRCC assess how Houston's air pollution is affecting our ecosystem. Because of budget cuts, and inexpensive, readily available environmental indicator organism is needed. It seems that lichens and the invertebrates that live on them may be ideal. Your job is to study these bioindicators and determine their current #'s and kinds on trees and compare your values to other areas and to past values, and report your findings.
- Select 10 trees for sample. Give each a #.
- Tie string 1.5 meters from ground
- GPS each tree
- Determine N,S,E,W using a compass
- Tape grid w/lower edge on string, align with N.
- Count what shows in each circle (type lichen, bare bark, moss, etc.) and record
- Repeat for each direction
- Repeat for all 10 trees
- For each tree, average data from 4 cardinal directions.
- Use cork borer to collect lichen sample from each tree
- Place lichen sample in Petri dish with distilled water and soak 24 hours
- Tally invertebrates seen
Assessment: Rubric, report, self-assessment, presentation
Enrichment/Reflection:
- Communicate finding to other students doing similar study (Margaret's study, Lorraine's study in WY, Path Science lichen study, and tardigrade study).
- Post results on school website
Resources: Earthworks community, Arboretum curator, Houston Museum of Nat. Sci., TNRCC, Harris County, Arboretum adjacent to campus, supportive colleagues, principal, district science director, U of H Environmental Center, Sierra Club
Barriers: Getting historical data
Strategies: Have students contact area resources for help in getting historical data. We may be first to do a lichen study in Houston!!
Go with the Flow! (Earthworks 2002)
How does the movement of water affect the chemistry of the water and the diversity of living things found in bodies of water?
Learning Objectives:
- Science process skills
- Math skills (measurement, mean, graphing, perimeter, length, area, volume, topographic maps, etc.)
- Physics (force & motion)'
- Chemistry (Physical & chemical properties & changes)
- Biology/Ecology (Finding patterns, dichotomous keys, making comparisons, etc.)
Where: Spring Branch Creek, SBISD Science Center pond (adjacent to my school campus. Extension: Buffalo Bayou
Who: 6th Grade Science/Math students, 32/ 2½ hour block. Myself (Edie) & my math co-teacher, Melanie; teams of 4 students
What: Compare a pond & a creek.
- Physical: temperature, pond dimensions & volume, creek measurements & velocity
- Chemical: Water quality tests using Hach kits - pH, DO, Nitrate & Phosphate
- Biological: Collect macroinvertebrates with dip nets, sort similar ones, ID using a simple dichotomous key.
What are the differences in these physical, chemical & biological factors between ponds (still water) & the creek (moving water)?
When: 1 time each month for each site during the school year or more as needed. (Both sites are very near to the school.)
Potential barriers: Money - Need to purchase Hach kits and small dip nets.
Strategies: SBISD $500.00 mini grant - easy to get!
Earth System Connections:
Atmosphere: Weather - GLOBE project, water cycle
Geosphere: Eventually study soils, minerals, nitrogen cycle
Human Impact: Effect of nitrate & phosphate run-off from residential fertilizers, discharge of detergents. Creek is heavily impacted urban area.
Extension: Students can compare ozone data from our school with ozone data from the greater Houston area, and in large cities in the United States. Students can locate the major sources of ozone pollution on a map of Houston , and research ways to reduce the ozone pollution in our city. Students can write to elected officials about their ideas.Students may be able to correspond with students in other Earthworks teacher's classes about ozone levels in their cities.
Atmospheric Chemistry/Weather Study (Earthworks 2001)
Who: 6th Grade Science Classes
What: On-going study of weather variables and correlation to air pollution in Houston, Texas.
Why: Science process skills, data collection, graphing and drawing conclusions, human impact on environment.
Where: School grounds.
When: A.M. & P.M., all year, 2001-2002
Potential Barrier: Need to purchase pollution sensor.
Materials: ozone sensor, CO2 sensor, Sensidyne pump& cartridges for SOx, NOx, general hydrocarbons, eco-badges, wind vane, wind meter, psychrometers, barometer, cloud charts, visibility meter
Methods: Teams of 4 rotate data collection in AM and PM, measuring temperature, visibility, relative humidity, wind direction, wind speed, barometric pressure, cloud type, ppm of ozone, CO, SOx, NOx, and hydrocarbons. Find monthly averages and look for connections between wind direction and levels of pollutants from refineries and freeways.
Connections Between Projects: Meteorology, chemistry, human impact, cycles & systems, science process skills such as data collection, graphing results, drawing conclusions, environmental issues, and community.
Extension: Students can compare information about their pond to that from other sites - slow and fast moving streams, ponds in other environments, and even correspond with other Earthworks teachers' classes.
|
About Us