Liquid Swine Manure Application Research Articles

Comparison of manure application methods on nutrient and metal loss to snowmelt

Manure injection is well documented to reduce rain-driven nutrient losses, but the effect on snowmelt-driven losses is less studied. This study examined the surface application versus injection of liquid swine manure on phosphorus (P), nitrate‑nitrogen (nitrate-N), zinc (Zn), manganese (Mn), iron (Fe), magnesium (Mg), and calcium (Ca) release from soils to snowmelt. Manure was applied in the fall of 2021 to four replicated plots of surface-applied or injected treatments, and boxes were installed to collect snowmelt in each plot, including four unmanured (control) plots. In the spring of 2022, the snowmelt was collected from each box for 10 days, volume was recorded, and analyzed for dissolved reactive P (DRP), nitrate-N, Zn, Mn, Fe, Mg, and Ca concentrations, and pH. The mean daily snowmelt volume and snowmelt depth ranged from 2.9 to 25.2 L, and 2.7 to 23.3 mm, respectively. The mean snowmelt DRP concentrations for manure injected, surface-applied, and control treatments were 0.66 ± 0.07, 0.89 ± 0.07, and 0.65 ± 0.07 mg L−1, respectively. The mean DRP concentration did not vary among the manure application methods for the first 5 days of snowmelt. However, DRP was significantly higher in the manure surface-applied treatment, compared to both control and manure-injected treatments on days 7 and 8, compared to the control on day 6, and compared to the manure-injected on day 9. The effect of the manure application method on nitrate-N (3.27 to 3.60 mg L−1) and metal concentrations in the snowmelt was not significant. The cumulative loads (mean across application methods and sampling days in kg ha−1) of DRP (0.56), nitrate-N (4.03), and metals [Zn (0.11), Mn (0.01), Fe (0.18), Mg (8.03), Ca (21.70)] mobilized with snowmelt flooding did not significantly vary among the manure application methods. Results suggest that DRP, nitrate, and metal loads were primarily controlled by the snowmelt volume rather than their concentrations. Therefore, land management practices that reduce the volume of snowmelt discharge could be more effective for reducing the P, nitrate-N, and metal loss to snowmelt from manured soils.

Effects of Mixed Application of Chemical Fertilizer and Liquid Swine Manure on Dry Matter Yield and Feed Value of Whole Crop Barley

Effects of Mixed Application of Chemical Fertilizer and Liquid Swine Manure on Dry Matter Yield and Feed Value of Whole Crop Barley

Effects of Mixed Application of Chemical Fertilizer and Liquid Swine Manure on Agronomic Characteristics, Yield and Feed Value of Rye (<i>Secale cereale</i> L.)

Effects of Mixed Application of Chemical Fertilizer and Liquid Swine Manure on Agronomic Characteristics, Yield and Feed Value of Rye (<i>Secale cereale</i> L.)

Liquid Swine Manure Application Variability: Challenges and Opportunities

HighlightsVariability of manure N content on the day of application was a major contributor to plot-to-plot N rate variability.Using the average of previous years’ manure samples is a valid strategy to improve the accuracy of P application.Estimated economic losses from missing target manure N rates averaged $34.27 ha-1 year-1 ($13.87 ac-1 year-1).Improving N rate accuracy with real-time N sensing provided an estimated value of $7 to $44 ha-1 ($3 to $18 ac-1).Abstract. Liquid livestock manure application presents both opportunities for replacing commercial fertilizer and challenges to doing so accurately. This study demonstrated the challenges in achieving a target N application rate using liquid swine manure on eighteen 0.4 ha research plots at the Northeast Research and Demonstration Farm (NERF) near Nashua, Iowa. Differences between the nutrient analyses of manure from a pre-application sample and samples taken on the day of application, equipment adjustments, field conditions, and changing manure nutrient content during pit pumping contributed to variability in the actual N rate applied. The coefficient of variability (CV) of manure N during manure pumping ranged from 2.7 to 13.6, with an 8-year average of 6.5. A weighted-average CV for applied manure volume ranged from 1.5 to 4.7, with an 8-year average CV of 3.2, suggesting that plot-to-plot variability in manure volume was less of an issue for achieving the target N rate than was the variability of manure N on the day of application. A separate analysis of manure from six Iowa swine farms showed that using the average of the previous years’ manure samples improved accuracy for phosphorus at Farm 2, whereas using a single sample from the application year improved accuracy for potassium at Farm 5. Averaged across the six farms, using the average of the previous years’ manure samples resulted in less error for phosphorus than using a single sample from the application year. For nitrogen, there was no significant difference between the two approaches within or across farms (p < 0.1). The average economic loss from missing the target N rate in the NERF study was $34.27 ± $32.49 ha-1 year-1 ($13.87 ± $13.15 ac-1 year-1). The estimated economic value from using real-time nutrient sensing to improve N rate accuracy ranged from $7.56 to $32.03 ha-1 ($3.06 to $12.96 ac-1) in a corn-soybean rotation and from $10.38 to $44.41 ha-1 ($4.20 to $17.97 ac-1) in continuous corn. This study illustrates the need for new technologies for real-time manure nutrient sensing and on-the-go rate adjustment. The economic analysis can serve as a guide for manure applicators when evaluating the feasibility of manure nutrient-sensing systems. Keywords: Manure application, Manure management, Manure nutrient content, Manure nutrient sensing, Manure rate calibration.

Long-term effects of liquid swine manure land surface application in an apple orchard field on soil bacterial community and heavy metal contents in apple (Malus pumila Mill.).

This study investigated the impact of liquid swine manure (LSM) land surface application in an apple orchard on soil health and copper (Cu) and zinc (Zn) in soil and apple. Three apple plots were selected, among which two for LSM application for 5 (AY5) and 11 (AY11) years with different application rates, a long-term inorganic fertilizer application plot as the control treatment (AY0). The soil and apple samples were collected for analysis of soil physicochemical properties, bacterial diversity and abundance, and the contents of Cu and Zn in soil and apple. Results showed that the LSM application significantly increased the concentration of soil nutrients with the highest in AY5, which has a high application rate of LSM. After 5 or 11 years applied, the content of total nitrogen (TN) in AY5 and AY11 increased by 125.2% and 96.7%, total phosphorus (TP) increased by 167.6% and 148.6%, and soil organic matter (SOM) increased by 180.7% and 120.6%, respectively. The AY5 treatment significantly lowered OTUs and decreased Shannon index trend with a negative correlation between soil organic matter and Shannon index. The six predominant bacterial phyla in different treatments were similar, but the LSM application significantly increased the abundance of Chloroflexi and Firmicutes. However, the abundance of Actinobacteria and Acidobacteria significantly decreased in AY5 as compared to control treatment, followed by a significant positive correlation between the abundance of Acidobacteria and soil pH. Besides, LSM application significantly increased the contents of soil Cu, Zn, and apple Zn. Overall, the results illustrated that appropriate application rate of LSM can effectively improve apple orchard soil quality and bacterial community structure, but it will increase the risk of heavy metal accumulation in soil and apples.

Long-term effects of liquid swine manure on soil organic carbon and Cu/Zn levels in soil and maize

Swine feed is often supplemented with Cu and Zn, but > 90% of the ingested metal is excreted, ultimately accumulating in soil treated with liquid swine manure (LSM) to meet nitrogen (N) requirements. A maize field experiment was conducted between 2002 and 2015 in the Ebro Valley (north-east Spain) to determine the effects of long-term LSM application at two rates [30 and 50 m3 ha−1, equivalent to ~ 220 (218) and ~ 390 (389) kg N ha−1] compared to 0 and 300 kg N ha−1 mineral fertilizer. The highest Cu concentration in plants (5.03 mg kg−1) was observed following the 300 kg N ha−1 treatment. The treatments did not affect plant Zn levels (~ 21 mg kg−1). All whole-plant and grain metal concentrations were lower than threshold values for animal and human ingestion (30 mg Cu kg−1 and 500–1300 mg Zn kg−1). After 12 years, the soil organic carbon (SOC) of 13 g kg−1 in the first year (2002) increased by 19% and 26% at the low and high LSM rates, respectively. Mineral fertilization (300 kg N ha−1) achieved a 22% increase in SOC and also the 0 kg N ha−1 control treatment caused the SOC to rise by 11%. LSM applications do not seem to have adverse effects on maize yields after 12 years of applications.

Responses of Soil Microbial Activity to Swine Manure Applications

The allocation of the large amount of swine waste from farms is an international concern. An efficient way of managing such waste is its use in farming. It is already known that the incorporation of organic waste into the soil significantly increases the microbial population. Therefore, the objective was to evaluate the impact of the use of swine manure on the soil microbiota in a Eutrophic Oxisol. The experiment was set up in a completely randomized design in a 6 × 4 factorial scheme (sixconcentrations of swine manure and four evaluation periods) with four replications. We evaluate the following characteristics: microbial respiration (C-CO2), microbial biomass (µC g-1 soil) and pH.: microbial respiration (C-CO2), microbial biomass (µC g-1 soil) and pH. A significant effect was found in the interaction between concentrations and time of incubation (p < 0.05) of swine manure on microbial activity in the soil. The amount of microbial carbon increased as a function of increased levels of liquid swine manure. No interaction was observed between concentrations and time of incubation for the pH. The evaluation of the isolated factors allowed to observe that the pH decreased as the doses of manure were incremented. Higher and lower pH values were found after 5 and 30 days of incubation. The application of liquid swine manure up to 6000 L ha-1 increases the release of CO2 and carbon in the microbial biomass. The applications of liquid swine manure cause a gradual reduction in soil pH.

Phosphorus Contents in the Profile of an Oxisol With Continuous Application of Liquid Swine Manure

This study aimed to evaluate the dynamics of phosphorus in the soil by the determination of phosphorus contents in an Oxisol cultivated with soybean during the 2016/2017 crop season, after 17 years of successive applications of liquid swine manure (LSM). The experiment was conducted in the experimental area of the University of Rio Verde. The treatments were: T1-control; T2-25 m3 ha-1 of LSM; T3-50 m3 ha-1 of LSM; T4-75 m3 ha-1 of LSM; T5-100 m3 ha-1 of LSM and T6-fertilization with mineral fertilizer. The subplots refer to soil depths: 0-10; 10-20 and 20-40 cm. The LSM was applied to the soil surface by spraying, before soybean sowing and the mineral fertilizer was applied to the furrow at the time of planting. After soybean harvesting, soil samples were collected at the studied depths for the determination of the contents of P in the soil. The contents of P in percolated water are within the concentration range considered adequate for human consumption. As for the contents of P in the soil, LSM applications on the soil surface increased the available soil P up to the depth of 20 cm. The highest dose of LSM applied to the soil promoted an increment of P contents that are within the safety range of the critical environmental limit of phosphorus (LCA-P), corresponding to 37% of this limit.

Management of liquid swine manure: impact on mineral nitrogen dynamics and corn yield

ABSTRACT The agronomic efficiency of liquid swine manure (LSM) depends on the use of strategies to mitigate nitrogen (N) losses after its application to the soil, and thus preserve its fertilizing potential. In order to evaluate the injection of LSM into the soil and the addition of a nitrification inhibitor, as ways to increase its efficiency as a N source to the corn crop in the no-tillage system, an experiment was carried out under an Aluminofferic Red Latosol. The used treatments were: one control, surface application (total area) of LSM, injection of LSM in furrows, surface application (total area) of LSM + dicyandiamide (DCD), injection of LSM + DCD in furrows, and mineral fertilization. The mineral N in the soil and number of rows per ear, number of grains per row, 1,000-grain mass and grain yield for corn were evaluated. One day after the application of the treatments, the recovery of the mineral N in the soil with the injection of LSM exceeded by 10 kg ha-1 that observed with the superficial application. With DCD, the recovery of anionic forms (NO2- and NO3-) in the soil was lower in the first 20 days after the application, with the change in the N dynamics caused by DCD resulting in a higher content of mineral N at 30 days after sowing. The transformation rate for the anionic forms of mineral N in the soil is reduced with the addition of DCD. The injection of LSM with DCD does not differ from mineral fertilization, in terms of corn grain yield.

Changes in soil chemical and physical properties in pasture fertilised with liquid swine manure

ABSTRACT: Chemical and physical properties of soil can be altered with the successive application of liquid swine manure (LSM), also known as slurry. Therefore, monitoring the impact of LSM is essential to an assessment of the potential agronomic and environmental benefits and risks associated with management practices. The aim of this study was to evaluate the effects of LSM on the chemical and physical attributes of soil under pasture (Cynodon spp.), located in southern Brazil. Four areas were sampled: three areas cultivated with Cynodon spp. pasture with successive applications of 200 m3 ha–1 y–1 of LSM for three, eight and 15 years; and untreated native forest as a reference. The soil attributes evaluated were: organic carbon (OC), active (pH water) and potential acidity (H + Al+ 3), nutrient availability (i.e., P, K, Ca, Mg, Cu and Zn), soil bulk density, macro, micro and total porosity. Successive applications of LSM on pasture reduced soil active acidity, and increased the soil organic C and plant-available N, P, Ca, Mg, Cu and Zn contents. These effects were more intense with time and in the shallowest layers, i.e. 0-10 cm. Excessive increases in P, Cu and Zn in the soil should be carefully monitored to minimize the contamination risks to soil, ground and surface waters. Soil physical attribute changes were more associated with land use (pasture versus native forest) than LSM use, and LSM applications induced slight improvements in the soil structural quality over time.

Fertilization with liquid swine manure increases productivity and improves the quality of Urochloa decumbens

This study aims at assessing the influence of mineral fertilization and biofertilizer from liquid swine manure (LSM) in productivity, levels of crude protein (CP), neutral detergent fiber (NDF) and Acid Detergent Fiber (ADF) of Urochloa decumbens. The experiment was carried out in a red Latosol under a Urochloa decumbens pasture, in a state of degradation with loss of vigor and forage productivity. The delineation chosen for this study was randomized blocks with six treatments (control without fertilization, control with use of mineral fertilizer and four unique concentrations of liquid swine manure biofertilizer (61 m3 ha-1, 121 m3 ha-1, 181 m3 ha-1, 241 m3 ha-1)). The application of residue has been split in two times on the surface of the soil, by means of a distributor of liquid waste with a fan-shaped application. Yield and bromatological features were evaluated for two years. Fertilization with LSM can fully replace mineral fertilizing in Urochloa decumbens pasture systems, resulting in an increase, as a result, in the dry mass yield from the dosage of 121 m3 ha-1 and the reduction in fiber content in neutral and acid detergent. The increments in yield were observed in the second year, while improvement in bromatological quality was observed from the first application of LSM.

Reactive Transport of Manure‐Derived Nitrogen in the Vadose Zone: Consideration of Macropore Connectivity to Subsurface Receptors

Core Ideas Manure N transformation was modeled with different soil pore connectivities to tile drains. Macropores facilitated NH4+ oxidation reaction products deeper in the profile. Nitrate losses to tile were best predicted by models using pores connected to tile drains. Macropores can be important conduits for surface‐derived nutrients to reach subsurface receptors. Accordingly, nutrient reactive transport processes in macroporous soils need to be well understood. In this study, steady‐state two‐dimensional reactive transport simulations with MIN3P‐THCm (version 1.0.519.0) were used to elucidate how soil macropore connectivity to tile drains can influence N transformations following liquid swine manure (LSM) applications to soil. Four different soil scenarios were considered: homogeneous sand, homogeneous clay loam, and clay loam with discrete macropores connected to or disconnected from the bottom boundary used to represent tile drain outflow. In relation to the homogeneous soils, macropores, overall, facilitated chemical diffusion into the adjacent soil matrix along their length and broadly augmented O2 ingress into the soil profile. These processes combined to critically control the spatial distribution of NH4+ oxidation reaction products. When used in transient simulation mode with field data observed at experimental tile‐drained plots that received LSM application, the model showed that simulated nitrate mass losses to tile are considerably higher and most realistic under the connected macropore scenario compared with the homogeneous or disconnected macropore scenarios.

Soil carbon and physical-mechanical properties after successive applications of swine and poultry organic waste

ABSTRACT In agricultural crops, the use of swine and poultry waste as organic fertilizers results in gains in the productivity and reduction of production costs, but it may also change the physical properties and mechanical behavior of the soil, either increasing or reducing its quality. This study aimed to investigate the influence of applying increasing doses of liquid swine manure (160 m³ ha-1 year-1, 320 m³ ha-1 year-1 and 480 m³ ha-1 year-1) and poultry litter (6 Mg ha-1 year-1, 12 Mg ha-1 year-1 and 18 Mg ha-1 year-1), along four years, on the physical-mechanical properties and organic carbon content of a very clayey Rhodic Eutrudox. The application of liquid swine manure and poultry litter increased the surface soil organic carbon contents. The soil density decreased, whereas the total porosity and macroporosity increased, with the addition of liquid swine manure and poultry litter. There were no significant changes in the soil susceptibility to compaction.

English

One major problem of swine production is the huge volume of manure generated; this involve difficulties in proper handling of the residue when applied to the soil, given that such elements can be toxic to the environment. This study examined the vertical movement of the P, K and mineral N in the soil profile cultivated with Cynodon dactylon cv. Tifton 85 which was submitted consecutively to rates of Liquid Swine Manure (LSM) application (four years). The experiment was done using a randomized block design with four replications in a split-plot arrangement, where the whole plots were semiannual applications (November, 2002 to September, 2006) of increasing levels of LSM (0, 30, 60, 90, 120 and 180 m3 ha-1); while the sub-plots were the soil samples at different depths (0-10, 10-20, 20-40, and 40-60 cm). The N-NO3- leaching was observed when application of LSM exceeded 90 m3 ha-1 twice annually or during the year, suggesting a limit level for fertilizer on Tifton 85 pastures. Phosphorous and potassium accumulation was observed at higher LSM rate, mainly at the 0-10 cm soil layer since the soil P levels increased up to the highest evaluated depth at the 180 m3 ha-1 LSM level. LSM meets the Tifton 85 nutritional requirement regarding N, P and K when applied semi-annually at the rate of 90 m³ ha-1 without causing pollution effects; although the grass production responds up to 180 m3 ha-1 levels. Key words: Cynodon dactylon, environmental contamination, mineral nitrogen, organic fertilizers. &nbsp

Quantitative real-time PCR-based assessment of tile drainage management influences on bacterial pathogens in tile drainage and groundwater

This study compared the impact of controlled tile drainage (CD) and freely draining (FD) systems on the prevalence and quantitative real-time PCR-based enumeration of four major pathogens including Arcobacter butzleri, Campylobacter jejuni, Campylobacter coli, and Helicobacter pylori in tile- and groundwater following a fall liquid swine manure (LSM) application on clay loam field plots. Although the prevalence of all target pathogens were detected in CD and FD systems, the loads of A. butzleri, C. jejuni, and C. coli were significantly lower in CD tile-water (p<0.05), in relation to FD tile-water. However, concentrations of A. butzleri were significantly greater in CD than FD tile-water (p<0.05). In shallow groundwater (1.2m depth), concentrations of A. butzleri, C. coli, and H. pylori showed no significant difference between CD and FD plots, while C. jejuni concentrations were significantly higher in FD plots (p<0.05). No impact of CD on the H. pylori was observed since quantitative detection in tile- and groundwater was scarce. Although speculative, H. pylori occurrence may have been related to the application of municipal biosolids four years prior to the LSM experiment. Overall, CD can be used to help minimize off-field export of pathogens into surface waters following manure applications to land, thereby reducing waterborne pathogen exposure risks to humans.

Does Liquid Swine Manure Application Timing and Nitrapyrin Affect Corn Yield and Inorganic Soil Nitrogen?

Core Ideas Nitrapyrin (Instinct) effectively slowed nitrification of swine manure. Delaying fall application of swine manure increased corn yields and N availability. Instinct enhanced corn production in years with greater than normal precipitation. Fall application of liquid swine (Sus scrofa) manure (LSM) is preferred but it can increase N loss potential. Delaying application of LSM or adding a nitrification inhibitor could reduce N losses. This study measured the effects of LSM application timing and nitrapyrin [2‐chloro‐6‐(trichloromethyl) pyridine] as Instinct on soil inorganic N and corn (Zea mays L.) production. Field experiments were conducted from 2010 through 2014 on clay loam soils (Aquic Hapludolls). Treatments consisted of two fall application timings (early and late) and three rates (0, 2.56, and 5.11 L ha−1) of Instinct. Manure was injected 10‐cm deep at 134 kg of available N ha−1. Additional treatments included a control and 134 kg ha−1 of N as anhydrous ammonia (AA) with and without nitrapyrin as N‐Serve. Treatments were arranged in a randomized‐complete block design with four replicates. Late fall application of LSM and Instinct use resulted in greater fall and early spring NH4–N concentrations in manure bands. When averaged across years, LSM applied late increased corn grain yields 0.5 Mg ha−1 compared with early application and yields were 0.5 to 0.7 Mg ha−1 greater with Instinct than without. An interaction between main effects showed the yield response to Instinct was greatest when LSM was applied early. Total N uptake and removal were greater with Instinct than without Instinct. In this study, delaying LSM application until late fall (November) and using nitrapyrin (Instinct) increased corn yields and N uptake in years with greater than normal spring precipitation.

English

The application of liquid swine manure (LSM) in the soil as biofertilizer is one of the most recycling alternatives adopted, because the nutrients contained in this residue can override, in part or totally, commercial fertilizers, crop productivity with a reduction in production costs. The goal with this work was to evaluate the use of LSM as a substitute of mineral fertilization on soybean culture in conditions of Savannah in 2014/2015. The experimental design was of randomized blocks with three replications. The treatments consisted of the use of mineral fertilizer recommended for soybean culture; without fertilization; and doses of LSM (25; 50; 75 and 100 m³ ha-1). The levels of N, P, K, Ca, Mg, Cu, Zn, Mn and Fe in leaves, seeds and dry matter from the shoot, plant height and productivity of grain was assessed. There was no statistical difference between treatments that received mineral fertilization (P and K) and the treatments that received pig manure, indicating that the use of pig waste as bio fertilizer on soybean fertilization may be a promising alternative. The mineral fertilizer in soybean culture can be replaced by shots of LSM from 80 m³ ha-1 with no losses in grain productivity in a clayey dystroferric Red Latosol. The applications of doses of pig manure generally did not promote increase in the content of nutrients in grains and in the extraction of nutrients by the aerial part of the soybeans plants. Key words: Bio fertilizer, successive applications, waste, organic fertilization, animal production, organic matter.

Evaluation of nitrate levels in groundwater under agricultural fields in two pilot areas in central Chile: A hydrogeological and geochemical approach

The aim of this study is to evaluate the impact of the application of industrial fertilizers and liquid swine manure in groundwater in two pilot agricultural areas, San Pedro and Pichidegua, which have been under long term historic use of fertilizers. A comprehensive hydrogeological investigation was carried out to define the geology and the groundwater flow system. Chemical and isotopic tools were used to evaluate the distribution and behavior of the nitrate in the groundwater. The isotopic tools included δ18O, δ2H and 3H, which provide information about the origin and residence time of the groundwater; δ15N-NO3- and δ18O-NO3-, which provide information about nitrate sources and processes that can affect nitrate along the groundwater flow system. The application rate of liquid manure and other fertilizers all together with land uses were also evaluated. The hydrogeological investigation identified the presence of a confined aquifer underneath a thick low permeability aquitard, whose extension covers most of the two study areas. The nitrate concentration data, excepting a few points in zones located near recharge areas in the upper part of the basins and lower areas at the valley outlets (San Pedro), showed nitrate concentration below 10 mgN/L at the regional scale. The isotope data for nitrate showed no influence of the liquid swine manure in the groundwater at the regional scale, except for the high part of the basins and the outlet of the San Pedro valley, which are areas fertilized by manure. This data showed that the regional aquifer on both pilot study areas is protected by the thick low permeability aquitard, which is playing an important role on nitrate attenuation. Evidence of denitrification were also found on both shallow and deep groundwater in the Pichidegua site. This study showed that a comprehensive hydrogeological characterization complemented by chemical and isotope data is key for understanding nitrate distribution and concentration in aquifers from areas with intensive agriculture activities.

Amending woodchip bioreactors with water treatment plant residuals to treat nitrogen, phosphorus, and veterinary antibiotic compounds in tile drainage

Treatment of drainage from agricultural production systems is one means to help improve water quality. Treatment of multiple pollutants, such as nitrogen and phosphorus together is a desirable attribute of systems that treat drainage and runoff from agricultural fields. In this study, the performance of inline woodchip (WC) only and woodchip bioreactors amended with 10% and 20% (vol) alum-based drinking water treatment plant residuals (WTR), were evaluated for treatment of N, P, and veterinary antibiotic compounds in tile drainage from field plots during, primarily, the <5oC non-growing season (fall 2013 to spring 2014) following land application of liquid swine manure (LSM) in fall. Removal efficiencies for both WC+10% WTR and WC+20% WTR amended bioreactors were significantly greater than woodchip only bioreactors for nitrate (NO3-N), total phosphorus (TP), and dissolved reactive P (DRP) (p<0.05). Median removal efficiencies for NO3-N ranged from 33% (WC) to 74% (WC+20% WTR). For total P, median removal efficiencies ranged between 28% (WC) to 64% (WC+10% WTR), and for DRP they ranged between 35% (WC) to 89% (WC+10% WTR). Removal efficiencies for NH4-N were not significantly different between WTR-amended and woodchip bioreactors. Removal efficiencies for a suite of veterinary antibiotic parent and transformation products, such as tylosin, chlortetracycline, and isochlortetracycline, were very high for all treatment systems (>80%); albeit often input concentrations were in the lower ngL−1 range. This study demonstrated the utility of reusing industrial waste products in bioreactors designed to treat tile drainage effluent from agricultural field plots over a Canadian winter period following the land application of liquid swine manure.

Changes in Soil Properties and Rice Production as Influenced by the Consecutive Application of Liquid Swine Manure in Paddy Field

Changes in Soil Properties and Rice Production as Influenced by the Consecutive Application of Liquid Swine Manure in Paddy Field