HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text Free Full Text (PDF) Free Alert me when this article is cited Alert me if a correction is posted Services Related articles in JEQ Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by Grande, J. D. Articles by Powell, J. M. Search for Related Content PubMed PubMed Citation Articles by Grande, J. D. Articles by Powell, J. M. Agricola Articles by Grande, J. D. Articles by Powell, J. M. Related Collections Surface Water Quality Soil Erosion Best Management Practices Phosphorus Animal Waste

Corn Residue Level and Manure Application Timing Effects on Phosphorus Losses in Runoff

^a Biological Systems Engineering Department, 460 Henry Mall, University of Wisconsin, Madison, WI 53706
^b USDA-ARS, Dairy Forage Research Center, Madison, WI 53706

View larger version (39K): [in a new window]   Fig. 1. Arrangement of treatment plots showing details of microplot location.

View larger version (18K): [in a new window]   Fig. 2. Effect of crop residue cover (%) on dissolved reactive phosphorus (DRP) concentration in runoff for three manure treatments. Data points are an average of four replicates from each of the four seasons. Residue cover ranges for the three harvesting schemes (G, grain; SH, high-cut silage; SL, low-cut silage) are highlighted. For clarity, confidence intervals are not plotted.

View larger version (17K): [in a new window]   Fig. 3. Effect of crop residue cover (%) on dissolved reactive phosphorus (DRP) load for three manure treatments. Data points are an average of four replicates from each of the four seasons. Residue cover ranges for the three harvesting schemes (G, grain; SH, high-cut silage; SL, low-cut silage) are highlighted. For clarity, confidence intervals are not plotted.

View larger version (13K): [in a new window]   Fig. 4. Influence of time since manure application on runoff volume and its impact on dissolved reactive phosphorus (DRP) load. Note that a change in runoff does not affect the DRP load due to the dependence on DRP concentration (see text for details). Data points are an average of four replicates. Trend lines correspond to all residue levels (G, grain; SH, high-cut silage; SL, low-cut silage) for Years I (2002) and II (2003). For clarity, confidence intervals are not plotted.

View larger version (18K): [in a new window]   Fig. 5. Effect of crop residue cover (%) on total phosphorus (TP) load for three manure treatments. Data points are an average of four replicates from each of the four seasons. Residue cover ranges for the three harvesting schemes (G, grain; SH, high-cut silage; SL, low-cut silage) are highlighted. For clarity, confidence intervals are not plotted.

View larger version (27K): [in a new window]   Fig. 6. Fraction of total phosphorus in the dissolved phase for spring and fall runoff (DRP, dissolved reactive phosphorus; TP, total phosphorus). Mean and standard deviation values correspond to three or four replicates (G, grain; SH, high-cut silage; SL, low-cut silage; N, no manure; F, fall manure; S, spring manure).

View larger version (33K): [in a new window]   Fig. 7. Phosphorus partitioning, on a mass basis, among the four particle size classes (from the top: 0–2, 2–10, 10–50, and 50–500 µm) for nine treatments (G, grain; SH, high-cut silage; SL, low-cut silage; N, no manure; F, fall manure; S, spring manure). Each bar represents a composite distribution of 9 to 15 replicates, based on the number of available samples, averaged over the four seasons.

View larger version (38K): [in a new window]   Fig. 8. Phosphorus enrichment ratios of eroded sediments from spring and fall rainfall experiments. Mean and standard deviation values of one to eight replicates represent combined data from Years I (2002) and II (2003). Bars with the same letter are not significantly different at the 0.05 probability level (G, grain; SH, high-cut silage; SL, low-cut silage; N, no manure; F, fall manure; S, spring manure).