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Soil Biodiversity Sampling techniques for school science. Dr Kerry Bridle Tas Institute Agricultural Research University of Tasmania Kerry.Bridle@utas.edu.au. Ms Anna Paice PICSE Science Education Officer School of Ag Science, UTAS Anna.Paice@utas.edu.au. What is PICSE?.
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Soil Biodiversity Sampling techniques for school science Dr Kerry Bridle Tas Institute Agricultural Research University of Tasmania Kerry.Bridle@utas.edu.au Ms Anna Paice PICSE Science Education Officer School of Ag Science, UTAS Anna.Paice@utas.edu.au
What is PICSE? • Primary Industry Centre for Science Education based at UTAS • National program • 8 Activity Centres • Attracting talented students to study science, suffering from major skills shortages • Teacher PDs, class visits, Industry Placement Scholarship for yr 11/12, Science Camps yr 10, classroom resources, UTAS Science Investigation Awards yr 5-12 www.picse.net
Rotation /break crop Remnant • Native woodland • Native grass understorey • Small in area (4ha) • Detached from other remnants • Grazed conservatively • Lucerne based pasture • Sown 5 years ago • Rotationally grazed Permanent pasture • Mixed Pasture: Lucerne, Introduced perennials, Annual legumes, Native grasses emerging • Sown 10 years ago • Rotationally grazed Crop • 2004 Barley • 2005 Oats and Vetch • 2006 Wheat Site selection for comparison
1/5 teaspoon of soil (~1g) contains: • 100 million bacteria • 1 million actinomycetes • 100, 000 funghi with hyphae, that if strung together would measure 5 metres in length • 75% soil biota are found in the top 10cm of soil – easy to find, look at and measure! www.bfa.com.au/_files/sustainable%20olive%20orchards%20pg27-28.pdf
Sampling patterns • X pattern for bulk sampling • Z pattern for bulk sampling
Getting a random sample using Excel • Random numbers generated in Excel – using command =rand()*50, then copy the formula to other cells. • Gives quadrat locations in metres along 8, 50 m long transects (T1-T8), two transects for each paddock on one farm
50m or 100m transects for sampling www.environment.utas.edu.au/documents/BiGGFieldDataManual.pdf
Soil Health slides… Relating Soil Health indicators to biodiversity is a great way of linking different concepts…
Salinity • Airdry soil sample warm, dry room for 24 hours • Crush dry sample, remove stones and grass • 1 in 5 dilution: 20mL soil + 100mL deionised water = 120mL total in measuring cylinder • Shake/stir to dissolve salts, allow to settle 10 mins • Test with salinity probe linked to datalogger • EC meter often in Waterwatch kits or available from Roberts rural supplies
Compaction • Screwdriver test: how deep does it penetrate? • Instead of expensive equipment called penetrometer • Can be used to compare land use areas: 4WD track, sheep track, open pasture, school lawn, remnant veg http://www.dpi.nsw.gov.au/agriculture/resources/soils/structure/compaction
Use Score Card to measure compactionBill Cotching (2009) Soil Health for Farming in Tasmania
Soil moisture • Take sample, weigh, oven dry overnight at low temp (~50°C), reweigh • To calculate percentage soil moisture: (Wet weight - dry weight)/dry weight x 100 • Why is this important? Affects earthworm counts, crop and pasture growth etc www.environment.nsw.gov.au/resources/soils/testmethods/mc.pdf
Soil pH • Dilute 1 part soil in 5 parts deionised water • Swirl pH meter in solution until reading stabilises • Record readings in triplicate and average
Use the following techniques to sample different soil biodiversity indicators Provide some example investigation questions for students to complete • “Science as a Human Endeavour” • “Science Inquiry Skills” • “Science Understanding”
Litter bags • Make the litter bags • Fill with toilet paper • Bury at different depths or in different land use types • Do a visual comparison of break down over 1-2 months • Use an un-buried paper as control for comparison • Indicates soil microbial biodiversity and health, also relates to temperature and moisture
Investigation Questions • Which type of toilet paper breaks down the fastest? • Which type of soil breaks down toilet paper the fastest? • Does soil moisture affect the rate of toilet paper break down? • What is the ideal depth to bury your toilet paper when camping?
Figure 3. Insert the strips into the ground. Figure 1. Cutting incision into the soil Figure 2. Lay strips at right angles to the cut. Cotton strip assay For soil microbial activity – indicator of soil health and biodiversity • Leave strips for 2 weeks, remove with trowel, strength test using wool micron tester or suspend bucket on hook and add water (1mL = 1g) until each strip breaks!! • Average results from different land-use areas, graph and present www.environment.utas.edu.au/documents/BiGGFieldDataManual.pdf
Investigation Questions • How can you measure the strength of different cotton strips? (methods, technology) • Which land use type has the most active soil organisms? • Relates to all the soil health measures, great way of discussing science content
Earthworm Counts • Dig down 10cm and place all soil onto plastic • Sort through carefully and count aestivating earthworms and adult earthworms • Take an individual of each type to identify later, preserve in metho • Do the same with next 10cm of soil • Make a standard sampling quadrat for all groups • Each groups needs shovel, quadrat, plastic sheet or bin liner, containers for collecting into and preserving vials/solution http://www.naturewatch.ca/english/wormwatch/how_to_participate/choosing_method/quantitative_sort.html
Investigation Questions • Which land use type has the highest earthworm count? • How does earthworm count change with depth in soil profile? • How does soil moisture or time of year effect earthworm counts?
Pitfall traps www.environment.utas.edu.au/documents/BiGGFieldDataManual.pdf
Figure 2. Backfill around liner. Figure 3. Position of cup at ground level. Figure 4. Inserting wire spacers. Figure 5. Completed pitfall trap with lid Figure 6. Adding Ethylene glycol. Figure1. Situating liner in the ground. Pitfall traps
Resources for using Pitfall Traps • Good Bugs, Bad Bugs on PICSE GrowSmart website: www.picse.net/GROWSMART • find a spider http://www.findaspider.org.au/ • soil invertebrates in Vic (similar to Tas) http://morwellnp.pangaean.net/browser/invertebrates.html
Investigation Questions • What is the difference in species diversity between organic, conventional and Integrated Pest Management (IPM) orchards? • What is the difference in number of insects in native grassland, bushland, gardens and cropland?
Research Example • Sticky traps from research at TIAR by Steve Quarrell in Tassie apple orchards • “good guys” in blue • “bad guys” in red
Using Scat Counts of native animals to determine stocking levels and grazing competition for pastures Copies of this fact sheet available from Anna Paice Anna.Paice@utas.edu.au
The Ecological Society of Australia will be holding its annual conference in Hobart in 2011 (from November 21-24th) Approximately 500 ecologists from Australia and overseas are likely to attend. We invite schools around Tasmania to participate in this event. We are still working out the details but would appreciate input from you regarding how this might happen. We are also keen to support statewide ecological surveys done by schools and colleges. A challenge is to come up with a statewide database (and some funds to develop it) that all the information can be stored in.
Free teacher resources for TQA Chemistry, Enviro, Biology Contact Anna Paice at Anna.Paice@utas.edu.au