| Autor: |
Anne Thomas, William J. Northcott, Alexandria Kravchenko, Timothy M. Harrigan |
| Rok vydání: |
2004 |
| Předmět: |
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| Zdroj: |
2004, Ottawa, Canada August 1 - 4, 2004. |
| DOI: |
10.13031/2013.16411 |
| Popis: |
Two runoff trials were conducted on the University Farms at Michigan State University in 2003 to compare the suspended solids and E. coli concentration in runoff from manured and non-manured cropland following conventional, aeration, and no-till tillage operations at three, ten and twenty-one days after tillage and manure application. A portable rainfall simulator with a 1.5 x 2 m plot size was used to simulate a continuous flow rainfall event with an intensity of 70 mm h-1 to generate runoff. The rolling-tine aerator caused little reduction in the vegetative cover of the grass pasture or the crop residue cover of the wheat stubble. Generally, the total suspended solids concentration in the runoff increased with tillage intensity. Suspended solids in the runoff increased at the pasture site and decreased at the wheat site when the manure slurry was applied. The manure slurry contained sawdust bedding that formed a protective crust over the soil surface at the wheat site. The crust reduced soil particle detachment and separated the soil surface from the runoff stream. When no manure was applied there were nearly six times more suspended solids in the runoff from the conventionally tilled ground as from the no-till ground. The greatest E. coli concentration in the runoff from the pasture site was from the no-till plots on day-3 after manure application, and the concentration decreased as tillage intensity increased and decreased with time from the no-till and aerated plots. The E. coli concentration in the runoff from the wheat site was generally lower than from the pasture site, but there were no clear trends across time or tillage methods |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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