
Arthropod Diversity and Cover Crops By Jeffrey Taylor August 11,2003 Pennsylvania State University
Arrival of the Study • Land owner Steve Groff is interested to see what the benefits of long-term cover cropping are
Hypothesis • Fields with the least disturbance and a cover crop would have the greatest diversity and abundance of arthropods
Study Area Most Disturbed -Long term no-till ~20 years Least Disturbed -Pasture and then 7 years in no-till www.oznet.ksu.edu/notill/ images/nf_corninmay2.jpg www.countryside-management.org.uk/ heathland/grazing.htm
Study Area • Sixteen plots • 4 Long term no-till with a cover crop • 4 Long term no-till without a cover crop • 4 Short term no-till with a cover crop • 4 Short term no-till without a cover crop
Study Area • 2003: Field corn in a rye cover crop • 2002: Soybeans in a rye cover crop http://www.sdnotill.com/membersh.htm
Methods of Collection Pitfall Trap Pitfall Trap Catches surface insects Tullgren Traps Catches soil insects
Methods of Calculation • Abundance -Addition of all insects caught • Diversity -Shannon index -D=-Σpilogpi
Factors • Diversity • Abundance • Herbivore • Predators • Detritivores
Collection Dates Tullgren: July 15, 2003 July 28, 2003 Pitfall: July 15-17, 2003 July 28-30, 2003
Orthoptera-crickets Hymenoptera-ants Isopoda-pill bugs Araneae-spiders In The Pitfalls Cricket Ant Pill bug
In the Tullgren Traps • Mites • Collembola-springtails • Diptera-flies springtail Mesostigmatid mite Mesostigmatid mite
Results a a treatments do not differ significantly at p> 0.05
Results a a a a a a b b b b a, b indicate treatments that differ significantly at p< 0.05
Conclusion • Only the tullgren traps were studied in-depth • Population may be migrating between plots • Abundance of Arthropods was greater in the long term no-till fields soils.usda.gov/sqi/SoilBiology/ATLAS103_LR.jpg
Conclusion • Michael Hutson studied that diversity may decrease as fertility of soil increases -competitors completely dominate fertile environments http://www.markscollection.com/christian/images/eden_riveroflife.jpg