Influence of feedlot manure amendments on runoff hydrology and sediment loss during transition between continuous and legacy phases

Little research has compared land application of stockpiled (SM) or composted (CM) beef feedlot manure with straw (ST) or wood-chip (WD) bedding on loss of reactive phosphorus (RP) in runoff. We conducted a 6 yr (2013–2018) rainfall simulation-runoff study and utilized surface (0–5 cm) soil collected from a long-term (since 1998) field experiment on a clay loam soil in southern Alberta, Canada. The treatments consisted of SM or CM with ST or WD bedding applied at 13, 39, and 77 Mg·ha−1 (dry weight), as well as an unamended control and mineral fertilizer treatment. Surface soil was collected from all treatments after 15–17 (C15, C16, C17; 2013–2015) continual annual applications, and then 1–3 yr (L1–L3, 2016–2018) into the legacy phase after manure applications were first discontinued in 2015. The soil was packed into runoff trays, and flow-weighted mean concentrations (FWMCs) and mass loads of RP5 (<5 μm filter) in runoff water were determined during rainfall simulations. Our findings generally supported our null hypothesis of similar RP5 losses for manure type (CM = SM) and bedding (ST = WD) for most years. Successively higher application rates increased RP5 loss by 32%–121%. Termination of long-term applications dramatically reduced FWMCs by 58%–77% and mass loss by 56%–65% from the C17 to L3 years. This suggests an accumulation of soil P during continuous phase and depletion during legacy phase; therefore, lower application rates or termination of applications may reduce RP5 loss in runoff.

Little research has compared land application of stockpiled (SM) or composted (CM) beef feedlot manure with straw (ST) or wood-chip (WD) bedding on loss of dissolved organic carbon (DOC) in runoff. We conducted a 6 yr (2013–2018) rainfall simulation-runoff study and utilized surface (0–5 cm) soil collected from a long-term (since 1998) field experiment on a clay loam soil in southern Alberta, Canada. The treatments consisted of SM or CM with ST or WD bedding applied at 13, 39, and 77 Mg·ha−1 (dry weight), as well as an unamended control and mineral fertilizer treatment. Surface soil was collected from all treatments after 15–17 (C15, C16, and C17; 2013–2015) continual annual applications and then after one to three legacy years (L1–L3, 2016–2018) after manure applications were first discontinued in 2015. The soil was packed into runoff trays, and flow-weighted mean concentrations (FWMCs) and mass loads of DOC in runoff water were determined during rainfall simulations. Mean DOC losses were generally significantly (P ≤ 0.05) lower for CM with ST bedding compared with the other manure type – bedding treatments in certain years and were consistent with this amendment having the lowest total carbon (C) content. The total C content of the amendments explained 92% of the variation in DOC concentration. Termination of long-term manure applications reduced FWMCs by 85%–91% and mass loss by 76%–89% from the C17 to L3 year. Therefore, our findings suggested that composting manure with ST or discontinued long-term manure application may reduce DOC loss in runoff.

Long-term application of feedlot manure and inorganic fertilizer to cropland may increase metals and trace elements in soils, and negatively impact agricultural land use. We sampled a surface clay loam soil at Lethbridge in southern Alberta after 16 annual applications (2014) of feedlot manure or inorganic fertilizer, as well as an unamended control. The manure treatments were stockpiled (SM) or composted (CM) feedlot manure with barley straw (ST) or wood-chips (WD), and were applied at 13, 39, and 77 Mg ha−1 (dry weight). The soil was analyzed for strong-acid extractable concentrations of selected metals (Al, Fe) and trace elements (As, Ba, Cd, Co, Cr, Cu, Li, Mn, Ni, Pb, Sr, Ti, V, and Zn). Manure type (SM versus CM) had little or no significant (P > 0.05) effect on the elements. Significantly greater As, Co, Cu, Fe, Li, and V were found for ST than WD at all or higher rates, and the reverse trend occurred for Cd at the highest rate. Cadmium (ST only), Cu, Sr, and Zn were increased by greater application rates, whereas most of the other elements were decreased. Concentrations were significantly increased by manure (Cu, Sr, and Zn) and inorganic fertilizer (Cd) compared with the unamended soil. Copper, Sr, and Zn were greater for manured than inorganic fertilizer treatments, and the reverse trend occurred for Al, As, Co, Cr, Fe, Li, Ni, and V. Although manure and fertilizer may increase certain elements in the soil, no concentrations exceeded the federal soil guidelines for agricultural land use.

Long-term application of feedlot manure to cropland may influence soil mesofauna. These organisms affect the health, structure, and fertility of soils, organic matter decomposition, and crop growth. The objective was to study the long-term (16-17 yr) influence of feedlot manure type and bedding on soil mesofauna over 2 yr (2014-2015). Stockpiled or composted feedlot manure with straw (ST) or wood-chip (WD) bedding (plus unamended control) was annually applied (13 Mg ha dry wt.) to an irrigated clay loam soil with continuous barley (). Intact cores were taken from surface (0-5 cm) soil in the fall, and the densities of Acari (mites) suborders and Collembola (springtails) families were determined. Manure type had no significant ( > 0.05) effect on soil mesofauna density. In contrast, there was a significant two- to sixfold increase in density with WD- compared with ST-amended soils of total Acari in 2014 and 2015, as well as total Collembola, total Acari and Collembola, oribatid mites, and entomobryid springtails in 2014. The bedding effect was attributed to significantly greater soil water content and lower bulk density for WD than ST. Density of soil mesofauna was not significantly greater in amended soils than in unamended soils. A shift by feedlot producers from stockpiled to composted feedlot manure application should have no effect on soil mesofauna density, whereas a shift from ST to WD bedding may increase the density of certain soil mesofauna, which may have a beneficial effect on soil.

ABSTRACTLand application of composted feedlot manure (CM) instead of stockpiled manure (SM) at increasing application rates to cropland, or use of wood-chip (WD) instead of straw (ST) bedding, may influence the nitrogen (N) balance and cause N surpluses. This could result in environmental losses of N to the atmosphere, surface, or ground waters. We determined the influence of manure type, bedding material, and application rate (13, 39, 77 Mg ha−1 dry wt.) on cumulative N inputs, outputs, and N balance (aboveground system) for a long-term (since 1998) field experiment where manure had been repeatedly applied for 2, 7, and 12 yr. The annual N inputs considered were N in organic amendments or inorganic fertilizer (IN), and N in irrigation water. The annual N outputs considered were N in crop uptake, NH3 volatilization, and N2O gaseous loss. After 12 applications, cumulative N deficits occurred for the unamended control (−1140 kg N ha−1) and IN treatment (−678 kg N ha−1), and cumulative N surpluses were found for the organic amendments (689 to 12,200 kg N ha−1). Manure type, bedding, and application rate influenced the N balance for the three timelines but their effects often involved two- or three-way interactions. The N balance after 7 and 12 applications was significantly lower for CM-WD treatment compared to CM-ST, SM-ST, and SM-WD at the 39 and 77 Mg ha−1 rates, suggesting that composted manure with wood chips might be used to reduce cumulative N surplus at these two higher rates in the longer term.

Long-term application of feedlot beef cattle manure amendments to cropland may enhance earthworm abundance by increasing soil organic carbon. The objective of this study was to determine the legacy effects of feedlot manure type [stockpiled (SM) vs. composted (CM)], bedding material [straw (ST) vs. woodchips (WD)], manure rate (13, 39, or 77 Mg ha−1), unamended control, and inorganic fertilizer treatments on earthworm abundance in a clay loam soil after 3–4 yr of discontinued applications following 17 annual applications. Earthworms were sampled (20 cm depth) in 2 yr (2017–2018), and ancillary soil properties also determined. The Aporrectodea genus was the dominant earthworm identified. Earthworm abundance was similar (P > 0.05) for amended and unamended or inorganic fertilizer treatments. Abundance at the 39 Mg ha−1 rate in 2018 was significantly (P ≤ 0.05) greater by four times for SM than CM with ST, but it was two times greater for CM than SM with WD. Abundance at the 13 Mg ha−1 rate in 2017 was significantly greater by 91% for ST than WD, but at the 39 Mg ha−1 rate, it was 10 times greater for WD than ST. In 2018, abundance was five times greater for WD than ST with CM, but it was similar with SM. Overall, short-term legacy effects occurred on earthworm abundance, but these effects varied with manure rate. Earthworm abundance was not increased by manure application, which suggested a carrying capacity not directly related to food resource.

Limited research exists on short-term legacy effects of land application of different feedlot manures on barley (Hordeum vulgare L.) yield and soil macronutrient (NO3-N, PO4-P, K, and SO4-S) supply. In a study conducted in southern Alberta, feedlot manures with straw (ST) or wood-chip (WD) bedding were either stockpiled or composted and applied annually to a clay loam soil at 13, 39, and 77 Mg ha−1dry wt. for 17 yr. Control treatments without any amendments or with inorganic fertilizer were included. In the second and third year (2016–2017) after discontinuing manure applications in 2014, barley silage yield and soil nutrient supply measured in situ with plant root simulator (PRS®) probes were determined. No significant (P > 0.05) treatment effects occurred on barley yield. Significant treatment effects occurred on soil nutrient supply, but these depended on date and interaction with other treatment factors. Manure rate generally increased soil nutrient supply. Soil NO3-N and PO4-P supply were 40%–59% lower for composted manure with ST than the other three manure type-bedding treatments, and they were 26%–53% greater for stockpiled than composted manure. This indicated variable manure type effects at different dates. At the two highest rates, soil K supply was 60%–106% greater for ST than WD bedding, and the reverse trend occurred where SO4-S supply was 40%–174% greater for WD than ST bedding. Overall, short-term legacy effects of feedlot manure type and bedding were more persistent on soil macronutrient supply than barley silage yield.

The environmental impact of using wood chips instead of straw bedding with feedlot manure on transport and leaching potential from feedlot manure is unknown. Our main objective was to determine if transport of total N, total organic N, NO-N, and nonpurgeable organic C (NPOC) to subsurface soil was lower for soils amended with feedlot manure if combined with wood chips compared with straw. A secondary objective was to compare transport of N and NPOC with organic amendments versus inorganic fertilizer. Stockpiled feedlot manure (SM) with wood chip (SM-WD) or barley straw (SM-ST) bedding at 39 Mg (dry wt.) ha, and inorganic fertilizer (IN) at 100 kg N ha, was applied annually for 13 yr to a clay loam soil in a replicated field experiment in southern Alberta, Canada. Intact soil cores were taken in fall 2011 (0-30 cm depth) from the three treatments, and the residual N and NPOC were eluted from the soil cores. Total N, total organic N, and NPOC were determined on filtered (1.0 μm) effluent samples that are primarily dissolved fraction but may contain some small particulate N and C. Peak concentrations, flow-weighted mean concentrations, and mass loss of total N, total organic N, NO-N, and NPOC were significantly ( ≤ 0.05) lower by 35 to 86% for SM-WD compared with SM-ST. Mean recoveries were also significantly lower for SM-WD than SM-ST by 0.07 to 8% (absolute difference). The transport behavior was similar for SM-WD and IN treatment, but solute transport was greater for SM-ST than for IN. Application of stockpiled feedlot manure with wood chips instead of straw bedding may be a beneficial management practice to reduce transport and leaching potential of N fractions and NPOC.

Limited research exists on legacy effects of land application of feedlot manure on accumulation, redistribution, and leaching potential of water-extractable organic carbon (WEOC) in soil profiles. We sampled a clay loam soil at six depths (0–1.50 m) 2 yr after the last application (2014) of 17 continuous annual manure applications (since 1998). The amendment treatments were stockpiled (SM) or composted (CM) feedlot manure containing straw (ST) or wood-chip (WD) bedding at three application rates (13, 39, and 77 Mg ha−1 dry basis). There was also an unamended control (CON) and inorganic fertilizer (IN) treatment. The soil samples were analyzed for concentrations of WEOC. The total mass or accumulation of WEOC in the soil profile was greater (P ≤ 0.05) by 1.2–3.3 times for the CM-ST-77 treatment than 12 of 14 other treatments, and it was significantly greater for amended than CON or IN treatments. The total WEOC mass was 14%–20% greater for CM-ST than CM-WD, SM-ST, and SM-WD treatments, and it was 16%–22% greater for CM than SM at the 39 and 77 Mg ha−1 rates. The 77 Mg ha−1 rate of the four manure type-bedding treatments had the significantly greatest (by 37%–527%) concentrations of WEOC at the six depths compared with other treatments, suggesting greater redistribution and leaching potential. Significant manure effects occurred on soil WEOC 2 yr after the manure was last applied following 17 continuous applications, and it indicated an increased risk of leaching potential at the higher application rate.

Little research has been conducted on the influence of land application of stockpiled feedlot manure (SM) containing either wood-chip (WD) or straw (ST) bedding on soil net N mineralization (Nm) and nitrification (Nn) rates during the barley (Hordeum vulgare L.) silage growing season. The stockpiled manure containing ST or WD bedding at 77 Mg (dry weight) ha−1 yr−1 was annually applied for 13–16 yr to a clay loam soil in a field experiment in southern Alberta. The net Nm and Nn rates were measured using the “in situ-soil core” method over 30–33 d (Nm1, Nn1) and 46–50 d (Nm2, Nn2) in each of 4 yr (2011–2014). Net Nm1 rates were generally significantly (P ≤ 0.05) greater for ST (1.0–1.9 mg N kg−1 d−1) than WD (0.1–0.9 mg N kg−1 d−1). Net Nn1 rates were also generally significantly greater for ST (0.9–2.0 mg N kg−1 d−1) than WD (0.03–0.9 mg N kg−1 d−1). Similar trends were found for Nm2 and Nn2. The Nn rates, however, were limited by NH4 supply during the incubations as Nm:Nn ratios were typically <1 with re...

Long-term application of feedlot manure to cropland may change the physical properties of soils. We measured selected soil (surface) physical properties of a Dark Brown Chernozemic clay loam where different amendments were annually applied for 15 (2013), 16 (2014), and 17 (2015) yr. The treatments were stockpiled (SM) or composted (CM) manure with either straw (ST) or wood-chip (WD) bedding applied at three rates (13, 39, and 77 Mg ha−1) and an unamended control. The effect of selected or all treatments on selected properties was determined in 2013–2015. These properties included field-saturated (Kfs) and near-saturated hydraulic conductivity or K(ψ), bulk density (BD), volumetric water content, soil temperature, soil thermal properties, and wet aggregate stability. The hypotheses that selected soil physical properties would improve more for treatments with greater total carbon in the amendments (SM &gt; CM, WD &gt; ST) was rejected. The exceptions were significantly (P ≤ 0.05) lower soil BD for SM than CM and WD than ST for certain dates, and lower soil thermal conductivity for WD than ST. Most soil physical properties generally had no response to 15–17 yr of annual applications of these feedlot amendments, but a few showed a positive response.

The short-term legacy effects following long-term (17 yr) feedlot manure application on CO2 efflux for a surface soil (clay loam) were studied over 2 yr (2016–2017) on a Dark Brown Chernozem in southern Alberta. The five treatments were stockpiled (SM) or composted (CM) manure with either straw (ST) or wood-chips (WD) bedding applied at 77 Mg·ha−1 (dry wt.) and an unamended control (CON). Surface soil efflux was measured during the growing season of the 2 yr using the dynamic, closed-chamber method. Ancillary measurements (soil water and temperature, total carbon, bulk density) were also obtained. Soil CO2 efflux was similar (P &gt; 0.05) among the four amended treatments in the first (0.63–0.86 g·m−2·h−1) and second (0.40–0.46 g·m−2·h−1) years. However, soil CO2 efflux was significantly greater for amended than unamended treatments by 54–110% in the first year (CON = 0.41 g·m−2·h−1) and by 33–53% in the second year (CON = 0.30 g·m−2·h−1). Soil CO2 efflux was similar for SM and CM in both years and was significantly greater for WD than ST bedding in the first but not second year. Weak positive correlations (r ≤ 0.39) occurred between soil CO2 efflux and total soil C, water-filled pore space (WFPS), and soil temperature. Overall, our findings suggested that legacy effects of manure may persist for 1–2 yr following discontinued applications, but are mostly restricted to greater soil CO2 efflux for amended than unamended soils.

Miller, J. J., Beasley, B. W., Drury, C. F., Larney, F. and Hao, X. 2015. Influence of long-term manure application on mineral composition of irrigated barley silage. Can. J. Plant Sci. 95: 759–770. The long-term effect of land application of manure type (composted vs. stockpiled manure), bedding type (wood-chips vs. straw), and application rate on feed quality of barley silage as feed for beef cattle is unknown. We measured selected minerals [P, Ca, Ca:P ratio, Mg, K, K:(Ca+Mg) ratio, Na, Fe, Mn, Zn, Cu] of irrigated barley silage (Hordeum vulgare L.) on a clay loam soil after 4 (2002), 7 (2005) and 11 (2009) years of annual applications of composted (CM) or stockpiled (SM) feedlot manure with wood-chips (WD) or straw (ST) bedding at three application rates (13, 39, 77Mg ha−1 dry wt.). The treatments also included an unamended control and inorganic fertilizer treatment. Manure type generally had inconsistent or no significant (P≤0.05) effect on the concentrations of these minerals in barley silage. Most crop minerals were generally greater under ST than WD. The findings for P, K, Na, and K:(Ca+Mg) ratio generally supported our hypothesis of greater crop concentrations with greater application rate, but Ca and Mg decreased at higher rates. Overall, our findings suggest that bedding and application rate have more potential than manure type for managing the feed quality of barley silage.

ABSTRACTThe influence of annual applications of composted (CM) or stockpiled (SM) beef feedlot manure with straw (ST) or wood-chip (WD) bedding on cation exchange capacity (CEC) of a clay loam soil in southern Alberta was examined after 1, 8, and 15 years. The hypotheses in our study were that soil CEC should be greater for amended than unamended soils; manure type and bedding should have no effect on soil CEC; and soil CEC should increase with greater manure application rate. After fifteen applications, the CEC was significantly greater for amended than unamended soils. Manure type had no significant (P > 0.05) effect on soil CEC after fifteen applications, and the mean soil CEC was 5% greater for WD than ST. Mean CEC was significantly greater by 7 to 12% for the 77 than the 13 and the 39 Mg ha−1 rates after fifteen applications. The soil CEC was increased by 0.061 cmolc kg−1 for a unit increase in application rate (Mg dry wt. ha−1 yr−1), and 96% of the variation in CEC for amended soils could be explained by application rate. Overall, bedding, rate, or adjusting both bedding type and manure rate (but not manure type), may be possible practices for feedlot producers to manage soil CEC.

In rural areas, unpaved roads can drive water quality degradation via sediment inputs. Excess sediment loss from poorly maintained unpaved roads to adjacent waterways blocks sunlight, decreasing primary productivity and increasing nutrient concentrations. This is particularly relevant to Arkansas, where 85% of county roads are unpaved; however, few studies have explored the impacts of unpaved roads in rural watersheds dominated by pasture. We sampled Brush Creek (Arkansas) to understand local (i.e., road crossing type) and watershed‐scale (e.g., land cover/use) controls on sediment loss. We collected monthly baseflow and four opportunistic storm flow samples for total suspended solids (TSS) upstream and downstream at bridge, culvert, and direct stream crossings. Mean TSS yields downstream versus upstream of road crossings were comparable, especially at bridge and culvert sites, indicating these road crossings may not be critical TSS sources. At the watershed scale, TSS load showed increasing trends as both total length of unpaved roads and area of pastureland in a subwatershed increased (linear mixed effects; β = 0.03, R2 = 0.41, p > 0.1; β = 0.67, R2 = 0.42, p = 0.07, respectively). Moreover, TSS yields were higher during stormflow than baseflow (26.87 ± 6.82 vs. 0.38 ± 0.04 kg km−2 day−1; unpaired t‐test, p < 0.01). Finally, seasonality influenced local and watershed patterns of TSS loss via variation in transport controls, including wet season conditions, discharge rates, and overland flow. Our findings indicate watershed‐scale characteristics are key contributors to sediment loss in rural watersheds. Targeted best management practice implementation should focus on unpaved roads and pasturelands during key transport periods to effectively protect downstream water quality.