Heavy manure-derived contamination of soils can make animal congregating areas nonpoint sources for environmental pollution. In situ soil stabilization is a cost-effective management strategy with a focus on lowering contaminant availability and limiting release to the environment. Soil stabilizing amendments can help mitigate the negative environmental impacts of contaminated soils. In this 2-yr study, we examined the effects of adding no amendment (control) or treating with alum [Al (SO)⋅18HO] or biochar as soil amendments on Mehlich-3 extractable soil P, Cu, and Zn contents, antimicrobial monensin concentrations, total bacteria (16S ribosomal RNA [rRNA] gene), antibiotic resistance genes (1 and B), and Class 1 integrons (1) in an abandoned beef backgrounding setting. The alum reduced soil P (1374 to 1060 mg kg), Cu (7.7 to 3.2 mg kg), and Zn (52.4 to 19.6 mg kg) contents. Both alum and biochar reduced monesin concentrations (1.8 to 0.7 and 2.1 to 1.1 ng g, respectively). All the treatments harbored consistent 16 rRNA concentrations (10 copies g) throughout. The B gene concentration (10 copies g) was lower than either the 1 or the 1 genes (10 copies g), regardless of treatments. However, concentrations of all genes in the soils of animal congregation areas were higher than those in background soils with the least animal impact. In contrast with the effect on other contaminants, the effect of soil amendments on bacteria with antibiotic resistance genes was not biologically significant. Future research should be directed toward evaluating effective alternative methods to mitigate these bacterial populations.

Farmers are looking for better management practices to utilize animal manure as an alternative to chemical fertilizers. A 2-year field experiment was conducted to study the effects of nitrogen (N) fertilizer source and application methods to Nicholson silt loam soil in central Kentucky, USA for no-till corn (Zea mays) production. The region has a temperate climate with a mean temperature of 14.5 degrees C and rainfall of 1300mm year(-1). Treatments included a control, 179kg N ha(-1) urea ammonium nitrate (UAN) applied as preplant and sidedress, and swine effluent that was applied by three methods: broadcast, injection, and Aerway. Injection method produced the greatest corn grain yield (11.88Mg ha(-1)) and biomass yield (18.9Mg ha(-1)) in 2007. Results demonstrated that the effluent application methods and the timing of UAN application may not be agronomically important for corn production in this region. Hence, more studies are needed on different soils in this region.

Biochar can remediate degraded soils and maintain or improve soil health, but specific and predictable effects on soil properties and crop productivity are unknown because of complex interactions associated with climate patterns, inherent soil characteristics, site-specific crop and soil management practices, and the source, production characteristics, and amount of biochar applied. This multi-location field study was designed and conducted to determine if consistent response patterns could be elucidated by controlling the type and amount of biochar applied, depth of incorporation, and soil/crop management practices as much as possible for six U.S. locations. When averaged for five reporting locations, biochar or biochar plus manure (bio+man) treatments significantly (P<0.001) increased surface (0–15cm) soil organic carbon (SOC) levels by 48 or 47%, respectively, relative to control treatments. The SOC levels for the manure only treatment were not significantly different from the control. No other measured soil properties showed significant biochar or biochar×manure interactions, even though applying manure significantly increased extractable K, Mg, Na, and P levels. Analysis of three or four years of pooled biomass yield data from the six locations showed a significant location effect (P<0.001), but treatment effects were not significant. However, dividing annual plot yields by the average for all control plots at each location created a dataset of relative yields that showed a significant location×treatment interaction and higher normalized yields (36%) due to biochar (P=0.017) at one of the six locations. Overall, we conclude that hardwood biochar produced by fast pyrolysis can be an effective soil amendment for increasing SOC levels within a broad range of temperate soils, but crop yield responses should be anticipated only when specific soil quality problems limit productivity.

Use of broiler litter (BL) nutrients for crop production benefits crops, soils, and aids in disposing manure. Understanding corn ( Zea mays L.) grain production and soil properties resulting from long‐term BL amendment helps establish a sustainable manure‐based corn production with low environmental risk potential. This study conducted at Bowling Green, KY, during 2005 to 2015 examined effects of supplying N requirement of corn grain crop monoculture by broiler litter (full broiler litter, FBL), 1:1 mixture of BL and inorganic N (half broiler litter rate, HBL), and chemical fertilizer (CF) on corn grain yield and post‐harvest soil properties under no‐till (NT) and conventional tillage (CT). The FBL produced significantly higher grain yield (10.1 Mg ha −1 ) than the HBL (9.6 Mg ha −1 ), but similar to CF (9.8 Mg ha −1 ). The FBL soils had greater cation exchange capacity (CEC), organic matter (OM), and total nitrogen (TN) (15.5 cmol kg −1 ; 45 and 2.9 g kg −1 ) than the HBL (12.3 cmol kg −1 ; 42.3 and 2.4 g kg −1 ) and CF (10.1 cmol kg −1 ; 35.5 and 1.7 g kg −1 ). The FBL and HBL soils had 478 and 270 mg P kg −1 ; 15.7 and 9.6 mg Cu kg −1 ; 40.9 and 21.1 mg Zn kg −1 levels, respectively. Soil pH increased in the FBL, but decreased in CF. Soil nutrient aggregation rate was greater in the NT. Having lower soil nutrient accumulation than FBL and equivalent grain production potential as CF, HBL offers a better option for corn grain production with BL than by FBL. Core Ideas This study examined effects of long‐term broiler litter amendment on corn grain yield and post‐harvest soil properties. Broiler litter at full and half rates has similar corn grain production potential as chemical fertilizer. Broiler litter induced high soil nutrient levels, but levels elevated by half litter rate was not environmentally significant. No‐till and conventional tillage treatments have similar agronomic benefits and environmental risks.

Contaminants associated with manure in animal production sites are of significant concern. Unless properly managed, manure-derived soil nutrients in livestock production sites can deteriorate soil and water quality. This 3-yr study evaluated a soil nutrient management strategy with four sequentially imposed management practices: 12-mo backgrounding (BG), manure removal from the feeder area (FD), 12-mo destocking (DS), and 12-mo grass hay harvesting (H) in a small backgrounding feedlot. Resulting soil nutrient levels, total (), and N cycling bacterial ( and ) populations after each management practice in feedlot feeder and grazing (GR) areas and in crop grown at the control location (CT) were measured. Irrespective of management practice, FD contained greater soil nutrient concentrations than the GR and CT. Regardless of management practice, total bacteria cells (1.4 × 10 cells g soil) and nitrate reducers (5.2 × 10 cells g soil) were an order of magnitude higher in the FD than in the GR and CT, whereas nitrifying bacteria concentrations (1.4 × 10 cells g soil) were higher in the GR. Manure removal from the feeder area reduced M3-P (39%), total C (21%), total N (23%), NH-N (47%), and NO-N (93%) levels established in the FD during BG. Destocking lowered total C and N (45%) in the FD and NH-N (47%), NO-N (76%), and Zn (16%) in the GR. Hay harvesting reduced all soil nutrients in the FD and GR marginally. The management strategy has potential to lower soil nutrient concentrations, control soil nutrient buildup, and limit nutrient spread within the feedlot.

Composting swine slurries has several advantages, liquid slurries are converted to solids at lower moisture, the total volume and weight of material is reduced and the stabilized product is more easily transported off-site. Despite this, swine waste is generally stored, treated and applied in its liquid form. High-rise finishing facilities (HRFF) permit liquid slurries to be converted to solids which are partially decomposed underneath the HRFF and then finished in compost windrows. The purpose of this study was to evaluate the effect of turning frequency and ambient weather conditions on biological, physical and chemical properties of composted slurry-woodchip mixtures from HRFF. Compost trials were conducted in either fall (FT) or spring (ST) and piles were turned once or three times per week or upon compost temperature reaching 65 degrees C. Physical, chemical and microbiological characteristics were measured over the course of 112 (FT) or 143 (ST) days of composting. Total carbon, total nitrogen (N) and inorganic N decreased in all piles. Ammonium decreased while nitrate increased in all piles (including unturned), but total N losses were greatest in piles turned more frequently during the ST. Microbial populations of nitrifiers were dominated by ammonia-oxidizing archaea (3.0 x 10(3)-4.2 x 10(6) cells g(-1) compost) but ammonia oxidizing bacteria (below detection to 6.0 x 10(5) cells g(-1) compost) varied in response to turning and compost temperature; denitrifiers were present in high concentrations throughout the process. Swine HRFF materials composted well in windrows regardless of turning frequency and despite significant differences in starting materials and low initial C/N. Volume reduction, low moisture and low readily degradable organic matter suggest that the finished compost would have lower transportation costs and should provide value as a soil conditioner. Published by Elsevier Ltd.

Nitrogen is one of the most important and costly nutrient inputs for crop production. Farmers are looking for better management practice to enhance production and reduce environmental impact. A 3‐yr field study was established to examine corn ( Zea mays L.) grain yield and nutrient uptake resulting from application of 168 kg N ha −1 as urea (U), urea‐ammonium nitrate (UAN), ammonium nitrate (NH 4 NO 3 ), poultry litter (PL), and similar rate of commercially available enhanced‐efficiency nitrogen fertilizers (EENF) as follow: polymer‐coated urea (ESN), SuperU, UAN + AgrotainPlus, and PL + AgrotainPlus in a no‐till corn production. Treatments were replicated four times in a completely randomized block design from 2009 to 2011. Aboveground plant biomass was harvested at physiological maturity each year to determine dry matter and nutrient uptake. Soil samples were taken three times per year to evaluate the status of the selected nutrients in soil. There was a significant increase in corn aboveground dry matter and grain yield with application of 168 kg N ha −1 compared with control treatment. There was no significant difference in corn grain yield or dry matter among the N sources. However, averaged across all N sources, corn grain yield (10.1 Mg ha −1 ) in 2009 was greater than grain yield (7.5 Mg ha −1 ) in 2010 and 2011, mainly due to higher rainfall and better distribution in 2009. Addition of AgrotainPlus to UAN and PL did not influence corn grain yield. Additional research is needed to evaluate EENFs under different climatic conditions and different management practices.

Manipulation of the plant root zone to reduce the impact of plant parasitic nematodes has been a goal of researchers. Addition of animal manure has a long history of improved soil quality and reduced soil-borne diseases. The objective of this research was to measure the agronomic benefits of broiler litter application to a soybean (Glycine max) crop under no-till and disk regimes and to assess the impact of broiler litter application on soybean cyst nematode (Heterodera glycines) reproduction. Field treatments included two levels of broiler litter (6.7 Mg ha-1 and 13.4 Mg ha-1). Plots were established in a field where according to University of Tennessee soil tests no P or K were needed. Application of broiler litter at both rates significantly increased plant height in 2008 (P = 0.0001) and also in 2009 (P = 0.002). The benefits of broiler litter for soybean growth as measured by plant height was observed regardless of the litter rate. Significant grain yield differences were observed in 2008 (P = 0.0025). Spectral measurements among treatments were highly significant in 2008 (P = 0.0001). Spectral measurements were highly correlated with plant height, grain yield, and H. glycines egg population density at harvest in 2008. Increased levels of P, Mg and Zn were present in the soil where broiler litter was applied. We did not find a significant effect of broiler litter application on H. glycines reproduction in field trials.La manipulacion de la zona radical de la planta con el fin de reducir el dano causado por nematodos fitoparasitos ha sido objeto de investigacion. Por mucho tiempo se han conocido los beneficios que la adicion de estiercol de animales tienen sobre la calidad del suelo y sobre la reduccion de enfermedades vegetales. El objetivo de este trabajo es evaluar los beneficios agronomicos de la aplicacion de residuos de avicultura a campos de soya (Glycine max) arados y sin arar, y medir el impacto de estas aplicaciones sobre la reproduccion del nematode quiste de la soya (Heterodera glycines). Los tratameintos de campo incluyeron dos niveles de residuos de avicultura (6.7 Mg ha-1 y 13.4 Mg ha-1). Los lotes se establecieron en un campo en donde, segun analisis de suelo realizados por la Universidad de Tennessee, no se hallaban deficiencias de P o K. La aplicacion de los residuos en las dos dosis aumento significativamente la altura de las plantas en el 2008 (P = 0.0001) y en el 2009 (P = 0.002). Los beneficios sobre el crecimiento de las plantas de soya fueron similares con las dos tasas de aplicacion. Se observaron diferencias significativas en la produccion de grano en el 2008 (P = 0.0025). La mediciones espectrales entre tratamientos fueron altamente significativas en el 2008 (P = 0.0001). Las mediciones espectrales estuvieron altamente correlacionadas con altura de planta, produccion de grano, densidad de poblacion del nematode quiste en el momento de la cosecha en el 2008. Se observaron niveles aumentados de P, Mg y Zn en el suelo tras la aplicacion de los residuos. No encontramos efecto significativo de las aplicaciones sobre la reproduccion de H. glycines.

Beef cattle backgrounding operations that grow out weaned calves for feedlot finishing contain several environmentally significant constituents. A better understanding of these constituents and their environmental distribution will aid in the development of effective management guidelines for sustainable beef production. This research investigated soil nutrients, bacterial, and veterinary pharmaceutical concentrations across a small backgrounding beef feedlot on a karst landscape. Results indicated that all contaminants were highly concentrated in the feeder area (FD) and were lower in the other feedlot areas. The FD soils had a pH of 8.2, 59 mg kg soil organic matter (SOM), 2002 mg kg soil test phosphorus (STP), 99.7 mg kg NH-N, and 18.3 mg kg NO-N. The other locations were acidic (5.9-6.9 pH) and contained 39 mg kg SOM, 273 mg kg STP, 21.5 mg kg NH-N, and 2.0 NO-N mg kg. Bacteria populations in the FD averaged 2.7 × 10 total cells, 3.9 × 10 spp., 2.9 × 10 spp, and 4.5 × 10 cells per gram of soil. spp. and spp. concentrations were 1 to 4 orders of magnitude lower at the other locations. showed lower dynamic range and was generally uniformly distributed across the landscape. Antibiotic and parasiticide concentrations in the FD were 86.9 ng g monensin, 25.0 ng g lasalocid, and 10.3 ng g doramectin. Their concentrations were 6- to 27-fold lower in the other feedlot locations. Contaminant management plans for this small feedlot will therefore focus on the feeder and nearby grazing areas where soil nutrients, bacteria populations, and veterinary pharmaceuticals were most concentrated.

Manipulation of the plant root zone to reduce the impact of plant parasitic nematodes has been a goal of researchers. Addition of animal manure has a long history of improved soil quality and reduced soil-borne diseases. The objective of this research was to measure the agronomic benefits of broiler litter application to a soybean (Glycine max) crop under no-till and disk regimes and to assess the impact of broiler litter application on soybean cyst nematode (Heterodera glycines) reproduction. Field treatments included two levels of broiler litter (6.7 Mg ha(-1) and 13.4 Mg ha(-1)). Plots were established in a field where according to University of Tennessee soil tests no P or K were needed. Application of broiler litter at both rates significantly increased plant height in 2008 (P = 0.0001) and also in 2009 (P = 0.002). The benefits of broiler litter for soybean growth as measured by plant height was observed regardless of the litter rate. Significant grain yield differences were observed in 2008 (P = 0.0025). Spectral measurements among treatments were highly significant in 2008 (P = 0.0001). Spectral measurements were highly correlated with plant height, grain yield, and H. glycines egg population density at harvest in 2008. Increased levels of P, Mg and Zn were present in the soil where broiler litter was applied. We did not find a significant effect of broiler litter application on H. glycines reproduction in field trials.

Poultry litter; which is a mixture of poultry manure and a bedding material, is typically land-applied using broadcast application. During rainfall events, nutrients from surface-applied litter may be transported in runoff water, into streams, rivers, lakes, and other water bodies. A four-band implement for subsurface band application of poultry litter and similar solid products in row crops and pastures was developed. A novel feature of the implement is its adjustable band spacing, from 25 to 102 cm (10 to 40 in) in 2.5 cm (1 in) increments. Prior to development of the four-band implement, a single-band implement was developed Using the implements, subsurface band application of broiler litter to row crops and pastures greatly decreased nutrient losses and bacterial concentrations in runoff water compared to surface broadcast application. Compared to surface broadcast application, subsurface band application increased cotton yield, improved cotton fiber length, and improved the efficiency with which cotton plants made use of the litter-derived nitrogen.

Overseeded winter annuals in bermudagrass [Cynodon dactylon (L.) Pers.] improve annual dry-matter (DM) yield and capture nutrients in fields receiving manure application. This study determined the DM and nutrient uptake responses of annual ryegrass (Lolium multiflorum L.), cereal rye (Secale cereale), berseem clover (Trifolium alexandrinum L.) and bermudagrass-winter fallow to 0, 50, 100 and 150 kg N ha(-1) applied approximately 2 months before a single spring harvest, and in addition to swine-effluent N (258 and 533 kg ha(-1) in summer 2000 and 2001, respectively). Under drought conditions in 2000, DM yield at the spring harvest was highest in ryegrass, and summer DM yield of bermudagrass was greater at 100 and 150 kg N ha(-1) than 50 kg N ha(-1) (P < 0.05). The concentration and uptake of N at the spring harvest increased linearly across N rates in both years (P < 0.05). Cover crops differed in N uptake in 2000 (P < 0.01) and values ranged from approximately 141 kg N ha(-1) in berseem clover to 86 kg N ha(-1) in rye. Per unit of N applied, uptake of N increased by approximately 0 409 kg ha(-1) in 2000 and 0 267 kg ha(-1) in 2001; uptake of P increased by 0.029 and 0.014 kg ha(-1) respectively. In 2000, uptake of P was responsive to N rate and this relationship was significant (P < 0.01) in winter fallow (slope = 0.032) and ryegrass (slope = 0.057). Increased uptake of N and P at the single spring harvest was due mainly to higher concentrations in herbage and not higher DM yield.

Poultry litter provides a rich nutrient source for crops, but the usual practice of surface-applying litter can degrade water quality by allowing nutrients to be transported from fields in surface runoff while much of the ammonia (NH3)-N escapes into the atmosphere. Our goal was to improve on conventional titter application methods to decrease associated nutrient losses to air and water while increasing soil productivity. We developed and tested a knifing technique to directly apply dry poultry litter beneath the surface of pastures. Results showed that subsurface litter application decreased NH3-N volatilization and nutrient losses in runoff more than 90% (compared with surface-applied litter) to levels statistically as low as those from control (no litter) plots. Given this success, two advanced tractor-drawn prototypes were developed to subsurface apply poultry litter in field research. The two prototypes have been tested in pasture and no-till experiments and are both effective in improving nutrient-use efficiency compared with surface-applied litter, increasing crop yields (possibly by retaining more nitrogen in the soil), and decreasing nutrient losses, often to near background (control plot) levels. A paired-watershed study showed that cumulative phosphorus losses in runoff from continuously grazed perennial pastures were decreased by 55% over a 3-yr period if the annual poultry litter applications were subsurface applied rather than surface broadcast. Results highlight opportunities and challenges for commercial adoption of subsurface poultry litter application in pasture and no-till systems.

Alternative N fertilizers that produce low greenhouse gas (GHG) emissions from soil are needed to reduce the impacts of agricultural practices on global warming potential (GWP). We quantified and compared growing season fluxes of NO, CH, and CO resulting from applications of different N fertilizer sources, urea (U), urea-ammonium nitrate (UAN), ammonium nitrate (NHNO), poultry litter, and commercially available, enhanced-efficiency N fertilizers as follows: polymer-coated urea (ESN), SuperU, UAN + AgrotainPlus, and poultry litter + AgrotainPlus in a no-till corn ( L.) production system. Greenhouse gas fluxes were measured during two growing seasons using static, vented chambers. The ESN delayed the NO flux peak by 3 to 4 wk compared with other N sources. No significant differences were observed in NO emissions among the enhanced-efficiency and traditional inorganic N sources, except for ESN in 2009. Cumulative growing season NO emission from poultry litter was significantly greater than from inorganic N sources. The NO loss (2-yr average) as a percentage of N applied ranged from 0.69% for SuperU to 4.5% for poultry litter. The CH-C and CO-C emissions were impacted by environmental factors, such as temperature and moisture, more than the N source. There was no significant difference in corn yield among all N sources in both years. Site specifics and climate conditions may be responsible for the differences among the results of this study and some of the previously published studies. Our results demonstrate that N fertilizer source and climate conditions need consideration when selecting N sources to reduce GHG emissions.

Surface application of broiler litter to no-till cotton could lead to degradation of water quality. Incorporation of broiler litter into the top surface soil (0.05 m) could alleviate this risk. A 2-yr field study was conducted on a silt loam upland soil to determine the effect of incorporation of broiler litter into the soil surface on nutrient and bacterial transport in runoff. The experimental design was a randomized complete block with four treatments and three replications. Treatments were (i) unfertilized control; (ii) surface-appliedbroiler litter at 7.8 Mg ha(-1) without incorporation; (iii) surface-applied broiler litter at 7.8 Mg ha(-1) with immediate incorporation; and (iv) inorganic fertilizer N (urea ammonium nitrate, 32% N) and inorganic fertilizer P (triple superphosphate) at the recommended rate. Phosphorus was surface appliedat 25 kg ha(-1) and N was injected at 101 kg ha(-1) into the soil using a commercial liquid fertilizer applicator. Runoff was collected from small runoff plots (2.4 m by 1.6 m) established at the bottom side of main plots (13.7 m by 6.0 m). Incorporation of broiler litter reduced total N (TN), NO3-N, water soluble P (WSP), and total P (TP) concentrations in runoffby 35, 25, 61, and 64%, respectively, and litter-associated bacteria by two to three orders of magnitude compared with unincorporated treatment. No significant difference in total suspended solids (TSS) in runoffwas obtained between incorporated and unincorporated treatments. Incorporation of broiler litter into the surface soil in the no-till system immediately after application minimized the potential risk for surface nutrient losses and bacteria transport in runoff.

More than 80% of broiler (chicken, Gallus gallus domesticus) litter produced annually is applied as a plant nutrient source, particularly for nitrogen (N) and phosphorus (P), to pastures. However, N losses during the process of litter N mineralization limit availability of N to crops. This study determined broiler litter N and P availability and apparent use efficiency (ANUE, APUE) to bermudagrass [Cynodon dactylon] during the first year after litter application. Treatments consisted of three litter rates (3.3, 6.6, and 13.2 Mg ha−1), a commercial N fertilizer rate that provided 358 kg N ha−1 as ammonium nitrate (NH4NO3), and an untreated control. Results showed bermudagrass dry-matter (DM) yield increased significantly with increase in litter rate. Commercial N fertilizer produced significantly greater DM yield than 3.3 and 6.6 Mg ha−1 of litter but produced less DM yield than 13.2 Mg ha−1 of litter. The overall average of ANUE from litter was 39% compared to the 59% from fertilizer. The mean litter N availabilities to bermudagrass during the first year after litter application were 48.5, 112.5, and 222 kg ha−1, corresponding to the 3.3, 6.6, and 13.2 Mg ha−1 litter rates, respectively. The overall mean of litter N mineralization, which was surface broadcast to bermudagrass plots during the first year, was 59.5% of the total litter N applied. The APUE, averaged across the rate and locations, was 13.6%, which was quite smaller than the ANUE of 39%. This finding of small APUE also validates the potential for P accumulation in soil after long-term animal manure application.

429 Soil Sci. Soc. Am. J. 74:429–435 Published online 8 Jan. 2010 doi:10.2136/sssaj2009.0076 Received 24 Feb. 2009. *Corresponding author (karamat.sistani@ars.usda.gov). © Soil Science Society of America, 677 S. Segoe Rd., Madison WI 53711 USA All rights reserved. No part of this periodical may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Permission for printing and for reprinting the material contained herein has been obtained by the publisher. Greenhouse Gas Emissions from Swine Effl uent Applied to Soil by Different Methods Soil Carbon Sequestration & Greenhouse Gas Mitigation