Dissolved Organic Carbon in Runoff and Tile‐Drain Water under Corn and Forage Fertilized with Hog Manure

Abstract

Dissolved organic carbon (DOC) export from soils can play a significant role in soil C cycling and in nutrient and pollutant transport. However, information about DOC losses from agricultural soils as influenced by management practices is scarce. We compared the effects of mineral fertilizer (MF) and liquid hog manure (LHM) applications on the concentration and molecular size of DOC released in runoff and tile-drain water under corn (Zea mays L.) and forage cropping systems. Runoff and tile-drain water samples were collected during a 2-mo period (October to December 1998) and DOC concentration was measured. Characterization of DOC was performed by tangential ultrafiltration with nominal cut-offs at 3 and 100 kDa. Mean concentration of DOC in runoff water (12.7 mg DOC L(-1)) was higher than in tile-drain water (6.5 mg DOC L(-1)). Incorporation of corn residues increased the DOC concentration by 6- to 17-fold in surface runoff, but this effect was short-lived. In runoff water, the relative size of the DOC molecules increased when corn residues and LHM were applied probably due to partial microbial breakdown of these organic materials and to a faster decomposition or preferential adsorption of the small molecules. The DOC concentration in tile-drain water was slightly higher under forage (7.5 mg DOC L(-1)) than under corn (5.4 mg DOC L(-1)) even though the application rates of LHM were higher in corn plots. We suggest that preferential flow facilitated the migration of DOC to tile drains in forage plots. In conclusion, incorporation of corn residues and LHM increased the concentration of DOC and the relative size of the molecules in surface runoff water, whereas DOC in tile-drain water was mostly influenced by the cropping system with relatively more DOC and larger molecules under forage than corn.

Manure and Fertilizer Effects on Carbon Balance and Organic and Inorganic Carbon Losses for an Irrigated Corn Field

“…The mean gross DOC concentration of furrow runoff in 2003 (11.6 mg L −1 ) was similar to the 12.7 mg L −1 reported in rainfall runoff from corn plots in Quebec, Canada (Royer et al, 2007). This Canadian study did not assess the year to year variability in runoff DOC.…”

“…Kindler et al (2011) used porous cup samplers to collect soil percolation water at 65-or 100-cm soil depths in different forest, grassland, and cropland ecosystems across Europe to estimate DOC losses, but did not attempt to evaluate effects of manure applications in these systems. Similarly, researchers have studied DOC losses in drainage water, tile-drain, and runoff from grassland soils and corn or hay fields, but did not consider other C-budget components (Don and Schulze, 2008;Royer et al, 2007). Other studies have examined the DOC loadings in surface water inflows and runoff for furrow-or flood-irrigated fields, but did not compare untreated soils with manured soils or measure other C inputs and outputs (Poch et al, 2006;King et al, 2009;Lentz and Westermann, 2010;Mailapalli et al, 2010;Ruark et al, 2010;Krupa et al, 2012).…”

Pesticide concentrations in frog tissue and wetland habitats in a landscape dominated by agriculture

“…The restored wetlands were designed to receive tile drainage water with high nutrient concentrations from surrounding agricultural fields to reduce nutrient exports to surface water. In the Midwest, tile drainage tends to have lower DOC compared to run-off (Royer et al, 2007) which mirrors the observed differences in DOC between the restored and reference wetlands.…”

Effect of Cultivation on Organic Carbon Pools and Nutrient Availability in Soil under Different Land Use System: A Review

“…Although DOC comprises of small fractions of soil organic carbon, it acts as a buffering agent in replenishment mechanism like desorption from soil colloids, dissolution from litter, and exudation from plant roots (Six et al, 2000). Dissolved organic carbon is an important component of C cycling and it is supposed to be most active and mobile form of organic matter in soil and considered as indicator of soil health (Kalbitz et al, 2000;Royer et al, 2007;Pan et al, 2010). Although DOC represents only small parts of C pools, it appears to be involved in many processes, such as translocation of nutrient and their biogeochemistry of N and P (Kalbitz et al, 2000) microbial decomposer activities (Peichl et al, 2007).…”