|Pitz, Scott - JOHNS HOPKINS UNIV|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: February 27, 2004
Publication Date: March 27, 2004
Citation: Pitz, S., Cavigelli, M.A. 2004. Varying hydrology of agro-ecosystems due to earthworm communities [abstract]. Mid-Atlantic Ecology Conference. Paper No. 84. Technical Abstract: Earthworms are probably the most significant soil invertebrates influencing soil characteristics and the other soil biota. The experiment was to see if earthworms contributed to significant differences in infiltration due to varying abundances of earthworms. The study site at the USDA Farming Systems Project has a long term experiment under way to test different crop rotations and management practices. The plots we used were limited to corn on the no-till, organic, and conventional systems. Earthworm activity was calculated by extraction sampling using mustard seed on 50 cm by 50 cm quadrats. Both biomass and density was higher in the no-till plots than in the organic and conventional plots (Biomass- 84/meter2 in no till and between 5/meter2 and 2/meter2 for organic and conventional, Density- 93/meter2 in no till and between 5/meter2 and 1/meter2 for organic and conventional). Infiltration measurements were gathered by using two types of devices. A small diameter double ring ponding infiltrometer was used to collect pair-wise comparisons between areas with burrows and areas with no burrows. The second infiltration device was a Cornell rainfall simulator. This device can be calibrated to replicate different rainfall rates and can provide not only infiltration rates but also sorptivity and hydraulic conductivity values. The ponding infiltrometer clearly demonstrated the differences between areas with burrows and areas without, with the infiltration rates varying by orders of magnitude. The rainfall simulator showed the differences in infiltration due to management practices. The organic and till plots had very high infiltration rates after tilling and as the soil settled, the infiltration rates decreased accordingly.