Poultry Litter Application Research Articles

Elevation map-based variable rate poultry litter application is a promising method in cotton production

Variable rate poultry litter (PL) application can potentially increase cotton yield and reduce environmental degradation risks associated with excess applications. The objective of this study was to determine whether applying PL in an inherently variable cotton field as variable-rate based on soil organic matter (SOM, VRo) or elevation (VRe) maps leads to greater yield and production efficiency than applying by the traditional uniform rate (UR). Poultry litter was applied by varying the rate within ±20 % of the target rates (7.9–11.2 Mg ha−1) where the highest elevation or lowest SOM regions received the highest rate, and the lowest elevation or highest SOM regions received the lowest rate. A treatment fertilized with conventional synthetic fertilizers served as the standard control (Std). Cotton fertilized with PL, regardless of the application method, provided greater K, S, and P nutrition and increased lint yield by as much as 30 % relative to the Std treatment. Applying the PL by the VRe method increased the production efficiency (yield per unit applied PL) by nearly 13 % over the UR. The VRo treatment resulted in a yield reduction of up to 11.8 % but the production efficiency was 14.2 % greater than the UR treatment. Variable rate application based on SOM was not as effective as that based on elevation. The results overall show that PL was superior to synthetic fertilizers in this soil and this superiority could further be enhanced by applying the PL as variable rate based on elevation maps.

Qualities and Quantities of Poultry Litter Biochar Characterization and Investigation

Excessive land application of poultry litter (PL) may lead to surface runoff of nitrogen (N) and phosphorus (P), which cause eutrophication, fish death, and water pollution that ultimately have negative effects on humans and animals. Increases in poultry production in the Delmarva Peninsula underscore the need for more efficient, cost-effective, and sustainable disposal technologies for processing PL instead of direct land application. The pyrolysis conversion process can potentially produce nutrient-rich poultry litter biochar (PLB), while the pyrolysis process can change the N and P to a more stable component, thus reducing its runoff. Pyrolysis also kills off any microorganisms that would otherwise trigger negative environmental health effects. This study is to apply an integrated method and investigate the effect of pyrolysis temperature (300 °C, 500 °C), poultry litter source (different feedstock composition), and bedding material mixture (10% pine shavings) on PLB qualities and quantities. Proximate and ultimate analysis showed PL sources and bedding material addition influenced the physicochemical properties of feedstock. The SEM and BET surface results indicate that pyrolysis temperature had a significant effect on changing the PLB morphology and structure, as well as the pH value (7.78 at 300 °C vs. 8.78 at 500 °C), extractable phosphorus (P) (18.73 ppm at 300 °C vs. 11.72 ppm at 500 °C), sulfur (S) (363 ppm at 300 °C vs. 344 ppm at 500 °C), and production yield of PLBs (47.65% at 300 °C vs. 60.62% at 500 °C). The results further suggest that adding a bedding material mixture (10% pine shavings) to PLs improved qualities by reducing the content of extractable P and S, as well as pH values of PLBs. This study also found the increment in both the pore volume and the area of Bethel Farm was higher than that of Sun Farm. Characterization and investigation of qualities and quantities of PLB using the integrated framework suggest that PL from Bethel Farm could produce better-quality PLB at a higher pyrolysis temperature and bedding material mixture to control N and P runoff problems.

Agronomic and economic productivity of summer annual forage systems under different poultry litter application methods

AbstractPoultry litter (litter) is a nutrient dense fertilizer that increases nutritive value and yield in pastures in the mid‐southern US. Nutrient losses due to runoff and nitrogen volatilization are common when broadcasting litter. As such, incorporating litter below the soil surface (subsurface) was evaluated in comparison to broadcasting in 2021 and 2022 by quantifying yield and nutritive value of annual forages. The study was a randomized complete block design with three forage treatments—sorghum‐sudangrass only (Sorghum bicolor L.), cowpea only (Vigna unguiculata L.), and their mixture, and three litter application methods (broadcast, subsurface, and a no litter control). Litter was applied in 2021 only as biennial application is common to save on application cost. Nutritive analyses included neutral detergent fiber and crude protein (CP). Partial budgeting led to relative profitability estimates by accounting for yield and cost differences across treatments. In comparison to the second‐highest yielding forage mixture, sorghum‐sudangrass yielded 4.5%–18.4% more regardless of litter application method. The forage mixture did not improve forage nutritive value, as cowpea were vastly outcompeted and did not average more than 5% of the total forage harvested in mixtures. Cowpea yields did not benefit from litter application. Subsurface application resulted in 8%–10% greater CP content compared to no litter and broadcast litter, respectively, across all forage species. Sorghum‐sudangrass with subsurface applied litter earned nearly $70/acre more than sorghum‐sudangrass with broadcast litter, the next highest treatment combination, and, with lesser nutrient loss.

Leaching of antibiotic resistance genes and microbial assemblages following poultry litter applications in karst and non-karst landscapes

Antibiotic resistance is increasingly recognized as a critical challenge affecting human, animal, and environmental health. Yet, environmental dynamics and transport of antibiotic resistance genes (ARGs) and microbial communities in karst and non-karst leachate following poultry litter land applications are not well understood. This study investigates impacts of broiler poultry litter application on the proliferation of ARGs (tetW, qnrS, ermB, sulI, and blaCTX-M-32), class 1 integron (intI1 i), and alterations in microbial communities (16S rRNA) within karst derived soils, which are crucial and under-researched systems in the global hydrological cycle, and non-karst landscapes. Using large, intact soil columns (45 cm diam. × 100 cm depth) from karst and non-karst landscapes, the role of preferential flow and ARG transport in leachate was enumerated following surface application of poultry litter and simulated rain events. This research demonstrated that in poultry litter amended karst soils, ARG (i.e., ermB and tetW) abundance in leachate increased 1.5 times compared to non-karst systems (p < 0.05), highlighting the influence of geological factors on ARG proliferation. Notably, microbial communities in karst soil leachate exhibited increased diversity and abundance, suggesting a potential linkage between microbial composition and ARG presence. Further, our correlation and network analyses identified relationships between leachate ARGs, microbial taxa, and physicochemical properties, underscoring the complex interplay in these environmentally sensitive areas. These findings illuminate the critical role of karst systems in shaping ARG abundance and pollutant dispersal and microbial community dynamics, thus emphasizing the need for landscape-specific approaches in managing ARG dissemination to the environment. This study provides a deeper understanding of hydrogeological ARG dynamics but also lays the groundwork for future research and strategies to mitigate ARG dissemination through targeted manure applications across agricultural landscapes.

Risk of weed seed and seedling emergence from poultry litter

AbstractIn areas surrounding large poultry industries, poultry litter is often an alternative nitrogen fertilizer for crop production. However, farmers who have not used poultry litter in the past have concerns regarding potential weed seed contamination. A survey was conducted to determine the occurrence of germinable weed seed in poultry litters (n = 61) submitted by growers and industry representatives across North Carolina. In a 9:1 potting media:poultry litter mix, a single grass seed germinated from the 61 surveyed poultry litters, equating to 0.3 viable seeds 100 g−1 poultry litter. Viable seed content averaged 1.1 seeds 100 g−1 litter using the extractable seedbank method on 25% of the litters from the survey, much higher than the grow out method, and the majority of seeds found were Amaranthaceae. A growth chamber experiment was then conducted and demonstrated that there was a negative relation between poultry litter application and weed seedling emergence. There was a 65%, 75%, and 85% reduction in Senna obtusifolia (L.) H.S. Irwin &amp; Barneby, Setaria pumila (Poir.) Roem. &amp; Schult., and Amaranthus palmeri S. Watson germination, respectively, from the control to highest application rate of poultry litter (26.9 Mg ha−1). A laboratory study showed that poultry litter leachates can decrease seed radicle length and integrity and is likely due to osmotic or salinity stress. The weed seed content in litter as well as the negative impact of poultry litter and its leachates on weed seedling emergence make it unlikely that poultry litter applications will significantly increase seedbanks above levels commonly observed in agricultural fields.

Cover Crop and Crop Rotation Effects on Tissue and Soil Population Dynamics of Macrophomina phaseolina and Yield Under No-Till System.

The effects of crop rotation and winter cover crops on soybean yield and colony-forming (CFU) units of Macrophomina phaseolina, the causal agent of charcoal rot (CR), are poorly understood. A field trial was conducted from 2011 to 2015 to evaluate (i) the impact of crop rotation consisting of soybean (Glycine max [L.] Merr.) following cotton (Gossypium hirsutum L.), soybean following corn (Zea mays L.), and soybean following soybean over a 2-year rotation and its interaction with cover crop and (ii) the impact of different cover crops on a continuous soybean crop over a 5-year period. This trial was conducted in a field with 10 subsequent years of cover crop and rotation treatments. Cover crops consisted of winter wheat (Triticum aestivum L.) and Austrian winter pea (Pisum sativum L. subsp. sativum var. arvense), hairy vetch (Vicia villosa Roth), and a fallow treatment was evaluated with and without poultry litter application (bio-cover). Tissue CFU of M. phaseolina varied significantly between crop rotation treatments: plots where soybean was grown following cotton had significantly greater tissue CFU than plots following soybean. Poultry litter and hairy vetch cover cropping caused increased tissue CFU, though this effect differed by year and crop rotation treatment. Soil CFU in 2015 was substantially lower compared with 2011. However, under some crop rotation sequences, plots in the fallow treatment had significantly greater soil CFU than plots where hairy vetch and wheat was grown as a cover crop. Yield was greater in 2015 compared with 2011. There was a significant interaction of the previous crop in the rotation with year, and greater yield was observed in plots planted following cotton in the rotation in 2015 but not in 2011. The result from the continuous soybean planted over 5 years showed that there were no significant overall effects of any of the cover crop treatments nor was there interaction between cover crop treatment and year on yield. The lack of significant interaction between crop rotation and cover crop and the absence of significant differences between cover crop treatments in continuous soybean planting suggest that cover crop recommendations for midsouthern soybean growers may need to be independent of crop rotation and be based on long-term crop needs.

Hazards Associated with the Combined Application of Fungicides and Poultry Litter in Agricultural Areas.

In recent decades, the poultry farming industry has assumed a pivotal role in meeting the global demand for affordable animal proteins. While poultry farming makes a substantial contribution to food security and nutrition, it also presents environmental and public health challenges. The use of poultry litter as fertilizer for agricultural soils raises concerns about the transfer of pathogens and drug-resistant microorganisms from poultry farms to crop production areas. On the other hand, according to the Food and Agriculture Organization of the United Nations (FAO), fungicides represent the second most used chemical group in agricultural practices. In this context, agricultural soils receive the application of both poultry litter as a fertilizer and fungicides used in agricultural production. This practice can result in fungal contamination of the soil and the development of antifungal resistance. This article explores the necessity of monitoring antifungal resistance, particularly in food production areas with co-application of poultry litter and fungicides. It also highlights the role of fungi in ecosystems, decomposition, and mutualistic plant associations. We call for interdisciplinary research to comprehensively understand fungal resistance to fungicides in the environment. This approach seeks to promote sustainability in the realms of human health, agriculture, and the environment, aligning seamlessly with the One Health concept.

Effect of Poultry Litter Application Method and Rainfall and Delayed Wrapping on Warm-Season Grass Baleage

Poultry litter is a widely available fertilizer in the southeast USA and subsurface application of litter can increase both forage production and nutritive value. Frequent rainfall events and high humidity often limit time available for hay curing; baled silage techniques can increase harvest time flexibility. Unfortunately, rainfall events can still occur without forecast during harvest events, resulting in delayed baling or wrapping. The objective of this study was to evaluate poultry litter amendment methods, subsurface (SUB) and surface (SURF), and the effect of no rain (NR) on bales with wrapping after 2 h compared with rained-on bales with 17 h delayed wrapping (RDW) on warm-season grass baleage fermentation and nutritive value. Data were analyzed as a randomized complete block design with two amendment treatments and two post-baling treatments. Crude protein (CP) was greater (p &lt; 0.01) and neutral detergent fiber (NDF) was lower (p &lt; 0.01) in both pre- and post-ensiled bales with subsurface-applied poultry litter. Rain and delayed wrapping resulted in lower pH (p = 0.03), starch (p &lt; 0.01), and water-soluble carbohydrates (p &lt; 0.01) in pre-ensiled bales, compared to those that did not receive rain and were wrapped within 2 h, while post-ensiled bales only differed in lower (p &lt; 0.01) starch and slightly greater (p &lt; 0.01) NDF in RDW. Lactic acid (p &lt; 0.01), acetic acid (p &lt; 0.01), and total acids (p = 0.03) were greater in SUB, while butyric acid tended to be greater (p = 0.09), and alcohols (p = 0.05) were greater in SURF. Bales from RDW and NR only differed by greater (p &lt; 0.01) propionic acid concentrations in NR. Under the conditions of this experiment, subsurface application of poultry litter increased final nutritive value, while rainfall and delayed wrapping of 17 h had few effects on the final nutritive value of warm-season grass baleage.

Managing cover crop C:N ratio and subsurface‐banded poultry litter rate for optimal corn yields

AbstractCover crops can be used to provide some of the nitrogen (N) needs of a cash crop to complement mineral fertilizers or manure, but there has yet been limited work to describe corn (Zea mays L.) yield as a function of cover crop quality and N inputs. We investigated the response of corn yield to gradients of both preceding cover crop C:N ratio and poultry litter (PL) application rates in Beltsville, MD during 2012–2014. To achieve different C:N ratios of the cover crops, hairy vetch (Vicia villosa Roth. "Groff") and cereal rye (Secale cereale L. "Aroostook") were seeded in a replacement series of six seeding rate proportions, resulting in shoot C:N ratios of 9.2:1 to 152:1 across years. For each hairy vetch/cereal rye sown proportions, PL was side‐dressed at corn V5–V8 stage in subsurface bands (SSB) at four targeted rates: Zero, P‐based (67 kg plant available nitrogen [PAN] ha−1), N‐based (135 kg PAN ha−1), and excess N and P (269 kg PAN ha−1). We found that corn yield followed a linear‐plateau relationship across these two dimensions. Within the linear region, each unit increase in log‐scaled cover crop C:N ratio resulted in a yield decrease of 2.56 ± 0.26 Mg ha−1 at a given rate of SSB PL. To optimize corn yields, we describe a model where each unit increase in log‐scaled cover crop C:N ratio required an additional 45.9 ± 6.22 kg PAN ha−1 from SSB PL. Yields following winter fallow were typically intermediate to the range of yields observed following the gradient of cover crop C:N ratios. We did not find significant differences in corn yield responses when comparing SSB PL to at‐planting incorporated or broadcast PL; we also found no significant differences between SSB PL and surface‐banded urea ammonium nitrate. Taken together, our approach of modeling yield response across two dimensions can be widely used to guide adaptive N management in subsequent cash crops following winter cover crops, thereby balancing both economic and environmental objectives in cover crop‐based cropping systems.

Using poultry litter for cotton phosphorus nutrition in Australia

AbstractIn the Riverina, NSW, Australia, abundant poultry litter (PL) could offer an alternative P nutrition source for irrigated cotton (Gossypium hirsutum L.). We assessed soil P availability, sequentially extracted P fractions, crop P uptake, and cotton yields using PL applications compared with mono‐ammonium phosphate (MAP) fertilizer in an alkaline Vertosol during the 2020–2021 season. Treatments were control, 150 kg MAP ha–1, 150 kg MAP ha–1 plus 4 Mg PL ha–1, and 4, 10, and 15 Mg PL ha–1. Crop P uptake (22–38 kg ha–1) at defoliation, seed P export (14–20 kg ha–1), P use efficiency (5.1–6.6 kg seed‐P Mg–1 lint), and lint yield (2,654–3,118 kg ha–1) were not different across treatments. Apparent recovery of P treatments was low (&lt;15%). Across treatments, soil Colwell‐P (0.5 M NaHCO3) were invariably high (23–70 mg kg–1) during crop‐growing season and did not differ from planting to first‐flower. Residual inorganic‐P (conc‐HCl‐Pi + H2SO4‐H2O2‐Pi) declined by 12% with concurrent increases in labile NaHCO3‐Pi (4%) and organic‐P (dil‐HCl‐Po [4%] and conc‐HCl‐Po [3%]) over 18‐mo (from pre‐trial baseline sampling to defoliation) across treatments. At defoliation, the 15 Mg PL ha–1 treatment had lower soil pH and exchangeable sodium percentage and higher soil total C, moderately‐labile soil organic‐P (dil‐HCl‐Po), Colwell‐P, and extractable K than the control, MAP, or 4 Mg PL ha–1 treatments. Although P applications may not improve lint productivity because of inherent soil P release within a single cropping‐season, PL (15 Mg ha–1) may fully substitute for commercial MAP fertilizer for soil P maintenance and improving soil conditions in surface‐irrigated high‐yielding cotton in southeastern Australia.

Effectiveness of Combined Biochar and Lignite with Poultry Litter on Soil Carbon Sequestration and Soil Health

Healthy soils are important to ensure satisfactory crop growth and yield. Poultry litter (PL), as an organic fertilizer, has proven to supply the soil with essential macro and micronutrients, enhance soil fertility, and improve crop productivity. Integrating this treatment has the potential to improve soil physical and biological properties by increasing soil carbon, C. However, rapid decomposition and mineralization of PL, particularly in the hot and humid southeastern U.S., resulted in losing C and reduced its effect on soil health. Biochar and lignite have been proposed to stabilize and mitigate C loss through application of fresh manure. However, their combined effects with PL on C sequestration and soil health components are limited. A field experiment was conducted on Leeper silty clay loam soil from 2017 to 2020 to evaluate the combined effect on soil properties when applying biochar and lignite with PL to cotton (Gossypium hirsutum L.). The experimental design was a randomized complete block involving nine treatments replicated three times. Treatments included PL and inorganic nitrogen, N, fertilizer with or without biochar and lignite, and an unfertilized control. Application rates were 6.7 Mgkg⋅ha−1 for PL, 6.7 Mgkg⋅ha−1 for biochar and lignite and 134 kg⋅ha−1 for inorganic N fertilizer. Integration of PL and inorganic fertilizer with biochar and lignite, resulted in greater soil infiltration, aggregate stability, plant available water, reduced bulk density and penetration resistance as compared to the sole applications of PL and inorganic fertilizer.

Perenniality drives multifunctional forage–biomass filter strips’ ability to improve water quality

AbstractVegetative filter strip characteristics such as perenniality drive hydrology and subsequent ecosystem services. However, the extent and the potential for forage–biomass crops to improve water quality, provide fodder, and optimize nutrient cycling in multifunctional systems is unknown. We evaluated (a) how species, perenniality, and plant community composition are linked to water quality; and (b) the multiuse forage–biomass potential of filter strips. Whole plots were species [eastern gamagrass (Tripsacum dactyloides), Kernza [or intermediate wheatgrass (Thinopyrum intermedium)], silphium (Silphium integrifolium), switchgrass (Panicum virgatum), and winter wheat (Triticum aestivum)], with split‐plots receiving 0 or 5.6 Mg ha−1 broiler litter. Rainfall simulations were conducted at 5 cm h−1 (until 30 min of continuous runoff) in summer and fall of 2019 and 2021 with dual forage and biomass harvests occurring 2019–2021. Kernza and silphium had the lowest biomass regrowth after forage harvests relative to native grasses, suggesting they would not be ideal multifunctional forage–bioenergy crops. Among all soil–plant–water variables, canonical correlations indicate poultry litter (.97), and soil phosphorus saturation (.77) were the most influential variables for water quality. Water quality score, FWQ, which is inversely related to runoff water quality, was lowest for switchgrass (0.03) and greatest (P ≥ .05) for eastern gamagrass and wheat (1.77 and 3.33, respectively), but not different from Kernza (0.98) and silphium (0.31). Therefore, switchgrass resulted in the best water quality scores and highest forage–biomass yields, with Kernza and silphium also showing promise for reducing sediment and nutrient loads following poultry litter applications in multifunctional filter strip systems.

Impact of biochar-compost derived from thermal pyrolysis of poultry litter and woodchips on N mineralization and maize growth in contrasting tropical dryland soils

A soil incubation and a greenhouse pot study was set up to determine the effects of biochar-compost mix on N transformation and availability and maize seedling performance on an alkaline and an acidic dryland soil. Urea fertilizer (F), sole application of poultry litter and woodchip biochar plus urea (PB + F & WB + F), biochar-compost mixture (1:1) plus urea derived from poultry litter (PB + C + F), woodchip (WB + C + F), and no amendment or urea application treatments were tested for N mineralization and soil properties. Results indicate that despite the unequal and high total N input, PB + C + F and WB + C + F mineralized less N of the total N input compared to urea (F), in the alkaline and acidic soil type. WB + C without F addition enhanced total N uptake comparable with F, and increased maize biomass in the alkaline soil. Addition of compost to WB (WB + C) enhanced maize P uptake and performed similarly as F.

Exploring alternate methods for predicting sorption-desorption parameters for environmental phosphorus loss assessment in poultry litter impacted soils.

Repeated applications of poultry litter (PL) in weathered soils cause soil phosphorus (P) accumulation and is a major environmental concern. Much remains unknown about the distribution of inorganic P (P i ) and organic P (P o ) forms along with their retention and release characteristics in soils that have had a history of PL application. The objectives of this study were to 1) determine P loss risk by investigating the distribution of P i and P o forms, P sorption-desorption parameters, and soil P saturation ratio (PSR; molar ratio of P/[Al + Fe]); and 2) predict the P sorption-desorption parameters using selected soil variables or soil test indicator, PSR. Forty soil samples from 10 random locations within seven pasture fields located in Piedmont soil region were selected and separated into four depths: 0–5, 5–15, 15–30, and 30–45 cm. These fields received annual PL applications ranging from 26 to 92 kg P ha -1 for the past 10 years. The P forms were determined using sequential P fractionation. Soil P retention characteristics were determined using Langmuir isotherm. Soil PSR was determined using oxalate extract (PSR Ox ). Surface 0–5 cm soils had significantly higher concentrations of labile P i , intermediately available P i , organic P pools, higher equilibrium P concentration (EPC), and PSR Ox compared to the lower depths, which indicated saturation of the P sorption sites from repeated PL application. Regression analyses used to predict P sorption-desorption parameters from soil test variables suggest inclusion of multiple soil variables, which may be time-consuming and not always feasible. The strong relationship between P sorption-desorption parameters and PSR Ox indicates that PSR Ox can be effectively used to predict P sorption-desorption parameters for the Piedmont soils without performing time-consuming batch isotherm experiments. Further studies would be needed to validate the relationship for other soil types under different environmental conditions. • P fractionation in poultry litter impacted soils identified intermediately available P i as the dominant pool in 0–5 cm soils. • Surface soils had lower P sorption capacity and higher desorption potential compared to the soils in lower depths. • P saturation ratio (PSR) was strongly related to P sorption-desorption parameters. • PSR can be effectively used to predict P sorption-desorption parameters for Piedmont soil region.

Preferential transport of phosphorus from surface‐applied poultry litter in soils from karst and nonkarst landscapes

AbstractPreferential transport of P in manure‐amended soils through soil macropores can be a substantial source of nonpoint P pollution, although studies quantifying P losses from intact soil columns are lacking. Large, intact soil columns (45 cm diam. by 100‐cm height) collected from karst and nonkarst landscapes (three replicates per soil) were used to evaluate the role of preferential flow in P leaching from surface‐applied poultry litter. Losses of P in leachate, dissolved P, and total P were quantified following poultry litter application (5.6 Mg ha–1) and three successive simulated rain events (3.9 cm h–1 for 2 h). Dissolved P constituted the major fraction of leachate‐P loss as more than 80% of TP, which peaked (5.61 mg L–1) following the first irrigation event after poultry litter application and decreased to about half (2.88 mg L–1) by the third irrigation event. Soils from the karst landscape had greater (p &lt; .05) leachate volume and total leached P, with approximately six times greater losses occurring than nonkarst soils. Results indicate that the top 1 m of soil obtained from karst landscapes is vulnerable to vertical P transport into deeper soil layers. Therefore, soils with substantial preferential flow pathways may increase legacy P in subsurface soil and pose a threat to surface and groundwater over time.

Interactive effects of poultry litter compost and chemical fertilizers on macronutrients, oil and protein content in sunflower (Helianthus annuus L.)

A field experiment was carried out at the research farm of Charfasson Govt. College, Bhola, during rabi season in 2016-2017 to evaluate the effect of poultry litter compost and NPK fertilizers on concentration, uptake, oil and protein content of sunflower cv. BARI-2 (Keroni-2). The experiment was laid out in a completely randomized block design (CRBD) having sixteen treatments with three replications. The unit plot size was 3 m x 2 m. Treatments were T1: Control (- PL and -NPK), T2:1.5 t PL ha-1, T3:3 t PL ha-1, T4: 4.5 t PL ha-1, T5:N40P30K50 kg ha-1, T6:N80P60K100 kg ha-1, T7:N120P90K150 kg ha-1, T8: 1.5 t PL ha-1+N40P30K50 kg ha-1, T9:1.5 t PL ha-1+ N80P60K100 kg ha- 1, T10:1.5 t PL ha-1+ N120P90K150 kg ha-1, T11: 3 t PL ha-1+N40P30K50 kg ha-1, T12: 3 ton PL ha-1+ N80P60K100 kg ha-1, T13:3 t PL ha-1+ N120P90K150 kg ha-1, T14: 4.5 t PL ha-1+N40P30K50 kg ha-1, T15:4.5 t PL ha-1+ N80P60K100 kg ha-1 and T16:4.5 t PL ha-1+ N120P90K150 kg ha-1. Sixty plants were grown in each plot for 90 days. Maximum values of NPKS concentration (%) in different organs of sunflower were 0.65, 0.42, 1.80, 0.17 for stem; 1.02, 0.54, 1.54, 0.18 for root; 4.47, 0.57, 3.14, 0.20 for leaf; 2.60, 0.64, 3.20, 0.32 for petiole and 5.18, 0.86, 1.02, 0.31 for seed due to application of poultry litter and NPK fertilizers. The highest concentrations of NPKS of different organs of sunflower at maturity, were found significantly (P&lt;0.05) higher in combined treatments 5 t PL ha-1 + N120P90K150kg ha-1 and 7.5 t PL ha-1 + N120P90K150kg ha-1, respectively, in most of the cases. However, their uptake pattern also followed the same trend as in concentration and those were found in same treatments in most of the cases. The lowest concentration and uptake were measured almost in control treatment (-PL and -NPK). Content of oil and protein increased variably due to variation in treatments. The highest content of oil in seed (47.7%) was extracted from the treatment 5 t PL ha-1 + N80P60K100kg ha-1 and the lowest value (37.7%) was recorded in the highest dose of NPK fertilizers and poultry litter which was lower than control treatment. Protein content also followed the same pattern as in oil. The highest content of protein (31.8%) was recorded from the treatment 5 t PL ha-1 + N120P90K150kg ha-1 and the lowest values (18.8%) was observed in control treatment. The overall findings of this study indicated that poultry litter compost in combination with chemical fertilizers can be applied to achieve better concentration, uptake of NPKS in different organs and oil and protein content in seeds of sunflower under field conditions at coastal zone. Dhaka Univ. J. Biol. Sci. 30(3 CSI): 359-369, 2022 (June)

Influence of poultry litter on nutrient availability and fate in plant-soil systems: A meta-analysis

Interest in using poultry litter (PL) as a nutrient source for crop production has increased in recent years. Utilization of PL can increase soil residual nutrients, thereby potentially increasing soil fertility and crop nutrient uptake. Conversely, PL addition may increase the transport of nutrients to the environment. This study aimed to elucidate the influence of PL on plant nutrient uptake, soil fertility, and environmental issues as compared to commercial fertilizer (CF) using a meta-analytic assessment. The synthesis was based on 134 studies (3,362 comparisons). Positive effects on soil fertility were observed, with PL significantly increasing cation exchange capacity (CEC), pH and soil carbon (C), total nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), copper (Cu), and zinc (Zn) concentrations compared to CF. Effects of PL on plant macro- and micronutrients varied depending on the plant tissue parts evaluated when compared to CF, with the leaves and stems generally having lower nutrient concentrations than the reproductive parts. Poultry litter influenced plant nutrient uptake, with a slightly negative effect being observed for N but significant positive effects for P and K. In addition, our results showed that litter application significantly increased carbon dioxide (CO₂) and nitrous oxide (N₂O) fluxes, but decreased nitric oxide (NO) emission. Subsurface-banding application of PL significantly decreased N and P loss in runoff. Overall, this meta-analysis validates the positive effects of PL on plant nutrient uptake and soil fertility and demonstrates that PL can be an effective alternative nutrient source to CF for crop production.

Soil Organic Carbon and Nutrients Affected by Tree Species and Poultry Litter in a 17-Year Agroforestry Site

Tree species and fertilization sources may affect the soil organic carbon (SOC) and fertility in agroforestry (AF) systems in temperate regions, but this remains unexplored. This study assesses the longitudinal trends in the SOC and major nutrients in a 17-year AF site established on an Ultisol in Fayetteville, AR. We evaluated how management and fertilization (mineral vs. organic) affect the soil’s physical and chemical properties using the tree species: red oak (Quercus rubra L.) and pecan Carya illinoinensis (Wangenh.) K. Koch. Long-term applications of poultry litter increased the soil pH, whereas the Mg and S concentrations decreased compared to the baseline levels (1999). Poultry litter increased the soil P concentration in 53% compared to the baseline levels and reduced the soil C:N ratio. After 17 years, increased Ca, SOC, and N concentrations were observed in the soils under the pecan stands that received poultry litter. Positive correlations occurred between the SOC and N (r = 0.96) as well as the Ca (r = 0.71) and P (r = 0.61) at a soil depth of 0–15 cm. Our findings demonstrated that the changes in SOC and fertility in the AF soils vary according to tree species and fertilization, mostly due to distinctive leaf litter and nutrient inputs. Organic matter accumulation increased the SOC retention and nutrient availability in the temperate AF systems.

Carbon footprint and net carbon gain of major long-term cropping systems under no-tillage

Due to increased contribution from agriculture sector to total greenhouse gas emissions, there is need to study the ability of no-tilled diverse cropping systems including crop sequences and bio-covers to mitigate C equivalent emissions. Thus, C-footprint was calculated for a long-term experiment at the University of Tennessee's Research and Education Center in Milan with six-crop sequences: continuous cotton (Gossypium hirsutum L.), cotton-corn (Zea mays L.), continuous corn, corn-soybean (Glycine max L.), continuous soybean, and soybean-cotton interacted with four bio-covers: poultry litter, hairy vetch (Vicia villosa), winter wheat (Triticum aestivum), and fallow control with three replicates in a strip-plot design. During the experiment duration (2002–2017), field inputs (fertilizers, pesticides, and machinery used for planting, chemical applications, and harvesting) and outputs (crop yield, aboveground, and belowground residue) were assessed for each crop sequence/bio-cover combination to calculate total C equivalence of inputs and outputs, net C gain, C footprint per kg yield, sustainability index, and nitrous oxide emissions. For continuous corn, C-based input emissions were significantly higher by 0.28–0.62 Mg CO2 eq. ha−1 yr−1 than all other sequences, however, a greater net C gain (5.4 Mg C eq. ha−1 yr−1) was also observed due to increased crop yield, aboveground and belowground residues. Poultry litter application resulted in lower C-footprint (1.59–2.09 kg CO2 eq. kg−1 yield) than hairy vetch, wheat, and fallow under all crop sequences. Hairy vetch also lowered C-footprint per kg yield (∼2–14%) when compared with wheat under continuous systems of corn, soybean, and cotton, and cotton-corn rotation. Poultry litter application increased sustainability index (23–45) of all cropping sequences compared with other bio-covers. Hairy vetch improved sustainability index of corn including cropping sequences as compared with wheat and fallow. Inclusion of soybean and cotton with corn significantly decreased nitrous oxide emissions by 20–25%. The major factor contributing towards C-based input emissions was N fertilizer with 68% contribution to total emissions on average. It is concluded that application of poultry litter can reduce per yield C-footprint and enhance production system sustainability compared with hairy vetch, wheat, and fallow for monocultures or rotations of corn, soybean, cotton. Additionally, hairy vetch can outperform wheat in reducing the per yield C-footprint for continuous corn/soybean/cotton, and cotton-corn rotation. Especially for corn production systems, hairy vetch can enhance sustainability index compared with wheat and fallow. In order to increase per hectare net C gain, reduce per yield C-footprint and enhance sustainability index simultaneously, integration of continuous corn or corn-soybean/cotton rotation with bio-cover poultry litter or hairy vetch may perform better than the monocultures of soybean or cotton integrated with bio-cover wheat or fallow control in the Mid-south USA.

Antioxidant system alterations and biological health status of earthworms following long-term exposure to antibiotic-contaminated poultry litter.

Poultry litter is widely applied as a fertilizer even though it is one of the main antibiotic sources to agricultural soils. Long-term sublethal effects (56 days) on the antioxidant system of Eisenia andrei earthworms following exposure to fluoroquinolone-contaminated poultry litter (enrofloxacin + ciprofloxacin) at 5.0, 10, and 20 g kg-1 were evaluated. The following biomarkers were assessed: superoxide dismutase (SOD), catalase (CAT), glutathione-S-transferase (GST), reduced glutathione (GSH), and a lipid peroxidation (LPO) proxy. Significant CAT and SOD increases, and a moderate positive correlation (ρ = 0.67, p < 0.05) between these enzymes was observed. Glutathione-S-transferase levels increased significantly at 10 g kg-1, while GSH exhibited a dose-dependent response at 5.0 mg kg-1 (4-106%), 10 mg kg-1 (28-330 %), and 20 mg kg-1 (45-472%). LPO levels exhibited a decreasing trend with increasing poultry litter concentrations of 8-170% (5.0 g kg-1), 7-104% (10 mg kg-1), and 3-6% (20 mg kg-1). A principal component analysis (PCA) highlighted increased SOD and CAT activities, possibly due to increased reactive oxygen species (ROS) concentrations. Biological health status assessments based on the biomarker response index indicate major alterations in the first month of exposure and becoming moderate in the second month. These findings indicate an antioxidant system attenuation trend. It is possible, however, that successive poultry litter applications may reduce the long-term recovery capacity of the evaluated biomarkers.