Bacterial Transport from Agricultural Lands Fertilized with Animal Manure

A plot scale study was conducted to determine bacterial transport in runoff from cropland treated with poultry litter and dairy manure applied at phosphorus (P) agronomic rates. Treatments included surface application of dairy manure, surface application of poultry litter, incorporation of dairy manure and control. A rainfall simulator was used to induce runoff 1 and 2 days after manure application. Runoff was analyzed to determine the concentration of indicator bacteria-fecal coliform, Escherichia coli, and Enterococcus. Observed edge-of-field bacterial concentrations were 10² to 10⁵ times higher than Virginia’s in-stream bacteria criteria for primary contact recreation waters. No significant treatment effects were observed on edge-of-field bacteria concentration or yield. Results suggest that the manure application based on agronomic P rates may yield significant bacterial loading to downstream waterbodies if rainfall occurs soon after manure application. This research underscores the need for BMPs that reduce runoff volumes and filter pollutants associated with animal manures.     

Impact of Time to First Rainfall Event on Greenhouse Gas Emissions Following Manure Applications

Use of inorganic fertilizers and manures are known to result in the release of greenhouse gases (GHG) to the atmosphere, and rainfall events can also increase GHG emissions from soils. The objective of this study was to examine how the time between fertilizer or manure application and the first rainfall event affects carbon dioxide (CO₂), nitrous oxide (N₂O), and methane (CH₄) fluxes. Swine manure, poultry litter, and urea were surface applied to plots. Rainfall was simulated 1, 4, 8, 15, or 29 days after application. Gas fluxes were determined before and after each rainfall simulation. Postrain CO₂ fluxes were the greatest from poultry litter at 4 to 8 days after fertilization, and all fertilizer treatments produced similar N₂O emissions with a peak 4 days after fertilization. These data seem to indicate that if manures are applied during drier periods of the year, GHG emissions can be minimized, in addition to reducing nutrient runoff losses.     

Ammonia volatilization from poultry manure-amended soil

Summary Poultry manure (PM) is commonly applied to cropland as a fertilizer, usually at rates determined by the nitrogen content of the manure. Limited information is available, however, on the volatilization of ammonia from poultry manure-amended soils, despite the effect these losses may have on the fertilizer value of the manure. This study was initiated to determine the influence of incorporation and residue cover on NH₃ losses from PM-amended soils. In the first experiment, a dynamic flow technique was used to measure NH₃ losses from 18 manures applied to a bare soil surface at a rate of 12 Mg ha^-1. In the second experiment, 3 of the 18 manures were incorporated either immediately, 24 h or 72 h after application. The third experiment compared the same three manures applied to a bare soil surface or to corn or soybean residues. Surface application of the manures resulted in the loss of from 4 to 31% of the total N applied in the manures. Incorporation of the PM with soil significantly reduced NH₃ loss with the greatest decrease following immediate incorporation. Crop residues either had no effect or slightly reduced NH₃ volatilization losses relative to PM application to a bare soil surface. Ammonia volatilization was not well correlated with individual manure properties, but a multiple regression approach using manure pH and total N content offered some promise as a means to segregate manures of the basis of volatilization potential.     

Poultry litter and tillage influences on corn production and soil nutrients in a Kentucky silt loam soil

Broiler chicken (Gallus gallus) manure, a rich source of plant nutrients, is generated in large quantities in southeastern USA where many row crops, such as corn (Zea mays L.), are also extensively grown. However, the use of broiler manure as an economical alternative source of nutrients for corn production has not been extensively explored in this region. This study was conducted to examine the use of broiler litter as a source of nutrients for corn production, as influenced by tillage and litter rate, and any residual effects following application. In addition, the consequence of litter application to soil test nutrient levels, particularly P, Zn and Cu, was explored. The treatments consisted of two rates of broiler litter application, 11 and 22 Mg ha⁻¹ on a wet weight basis, and one rate of chemical fertilizer applied under no-till and conventional tillage systems. Treatments were replicated three times in a randomized complete block design. Corn was grown with broiler litter and inorganic fertilizer applied to the same plots each year from 1998 to 2001. In 2002 and 2003, corn was planted no-till, but only N fertilizer was applied in order to make use of other residual litter nutrients. Soil samples were taken yearly in the spring prior to litter application and 4 years after the cessation of litter application to evaluate the status of the residual nutrients in soil. Two years out of the 4-year experiment, broiler litter application produced significantly greater corn grain yield than equivalent chemical fertilizer application and produced similar grain yield in the other 2 years. Corn grain yield was significantly greater under no-till in 1999, but significantly greater under conventional-till in 2000, and no difference between the two tillage systems were observed in 1998 and 2001. With 4 years of litter application, Mehlich-3 P increased from an initial 18 mg kg⁻¹ to 156 mg kg⁻¹ with 11 Mg ha⁻¹ litter and to 257 mg kg⁻¹ with 22 Mg ha⁻¹ litter. For every 6 kg ha⁻¹ of P applied in poultry litter Mehlich-3 P was increased by 1 mg kg⁻¹. Modest increases in Mehlich-3 Cu and Zn did not result in phytotoxic levels. This study indicated that an optimum rate of broiler litter as a primary fertilizer at 11 Mg ha⁻¹ applied in 4 consecutive years on a silt loam soil produced corn grain yields similar to chemical fertilizer under both no-till and conventional tillage systems and kept soil test P, Cu and Zn levels below values considered to be harmful to surface water quality or the crop.     

Measuring Water-Extractable Phosphorus in Manures to Predict Phosphorus Concentrations in Runoff

Water-extractable phosphorus (WEP) in manures can influence the risk of phosphorus (P) losses in runoff when manures are land applied. We evaluated several manure handling and extraction variables to develop an extraction procedure for WEP that will minimize pre-analysis manure-sample-handling effects on WEP measurements. We also related manure WEP determinations to runoff dissolved reactive phosphorus (DRP) concentrations found in previously conducted field simulated rainfall experiments using the same manures to evaluate WEP as a predictor of P runoff losses. Dairy and poultry manure WEP concentrations increased with manure-to-water extraction ratio and shaking time. Relative to fresh manures, drying and grinding dairy manures before analysis usually decreased WEP concentrations, while WEP in poultry manures was often increased. Pre-analysis handling effects on WEP were minimized at the 1:1000 extraction ratio with a 1-h shaking time. Relationships between manure WEP and runoff DRP concentrations were strongly influenced by season of year and WEP extraction procedure. The best prediction of DRP concentration in spring runoff experiments was with manure WEP concentration at the 1:1000 extraction ratio. With fall runoff studies, DRP concentrations were best predicted with WEP application rate rather than concentration. These seasonal differences can be explained by the greater percentage of rainfall that ran off in the fall compared to the spring. For all studies, runoff DRP concentrations were strongly related (r² = 0.82) to the ratio of runoff to rainfall volumes, confirming that models need to take runoff hydrology into account as well as manure WEP in P-loss risk assessments.     

Organic manure phosphorus accumulation, mobility and management

Abstract. Organic manures are an important source of P which can make a significant economic contribution to farm fertilizer policies. In the region of 119000 tonnes of P are returned annually to UK agricultural land in the form of manures collected and handled on farms, with an estimated 66000 tonnes of P applied to tillage land and 53000 tonnes to grassland.
Previous research on the utilization of manure P has tended to indicate a lower efficiency compared to inorganic fertilizer P in the season following application, but in the longer term manure and fertilizer P can be regarded as equivalent. Failure to adequately account for manure P additions to the land may result in soil enrichment which could increase the agricultural contribution to eutrophication, as a result of surface runoff or leaching.
Recent research has indicated that the current guidelines for minimizing runoff losses following the land spreading of manures are generally soundly based. However, there is a need for further research where manures are applied to cracking clay soils with underdrainage, and where rainfall soon after slurry application can increase surface runoff.
The careful cycling of manures within a properly devised fertilizer plan should minimize the risk of unnecessary soil P enrichment and subsequent leaching losses by restricting topsoil extractable P levels to less than 70 mg I^-1.     

Injecting Poultry Litter into Orchardgrass Hay

Traditional surface application of poultry litter leaves nutrients vulnerable to loss through volatilization and runoff. However, injection can increase capture of these nutrients in agricultural fields. Therefore, a field experiment was conducted to determine the effects of poultry litter injection on orchardgrass (Dactylis glomerata L.) hay yield and quality. Poultry litter was injected or surface applied using the Subsurfer poultry litter injector at the recommended agronomic rate (high) and half that rate (low) in 2012 and 2013 in an established field of orchardgrass. Soil was sampled to 15 cm and analyzed for soil nitrate. No significant differences in soil nitrate were detected between treatments. Although not always statistically significant, first cutting orchardgrass yields tended to be greater with surface litter application. Injected treatments had greater protein concentrations than their respective surface treatment, showing greater nitrogen uptake, when protein was weighted by yield. Protein was the same for high surface and low injected treatments showing that similar nitrogen (N) uptake was achieved.     

Transport of phosphorus in surface runoff as influenced by liquid and solid fertilizer phosphate addition

The effects of superphosphate (50 kg P ha^?1), applied as a liquid or a solid, on the transport of dissolved and particulate P in surface runoff from established pasture were evaluated using field plots and natural rainfall. An approximately 3-fold increase in the transport of both dissolved inorganic P and particulate P in surface runoff was measured in 14 weeks following fertilizer application in the solid form (2.9 and 2.9 % of the applied fertilizer P, respectively) compared to the liquid application (1.0 and 1.1 % of the applied fertilizer P, respectively). In addition, the application of solid fertilizer P had a more sustained effect on the concentration of both disolved and particulate P in surface runoff. The results are discussed in terms of the relative abilities of the applied fertilizers to move away from the zone of interaction between surface soil and runoff, their effect on the P enrichment of streams, and their agronomic effectiveness.     

Phosphorus and trace metal dynamics in soils amended with poultry litter and granulates

Environmental sustainability of animal agriculture is strongly dependent upon development of approaches to minimize the potential environmental impacts of applying animal manures. The excess manure and its nutrients (primarily phosphorus) in intensive animal production regions may need to be exported to other areas to comply with increased regulations on manure management. In our previous study we generated a variety of granulated products from poultry litter to achieve export of excess litter from the southwestern Ozarks, AR, USA. Our objective in the present study was to determine the effect of the application of poultry litter and granulated litter products on phosphorus (P), arsenic (As), copper (Cu) and zinc (Zn) dynamics in two Arkansas soils (Dewitt silt loam and Hector sandy loam). Poultry litter and granulated products were mixed with the surface horizon (0–15 cm) of soils at two application rates: P‐based (100 kg total P per hectare) and N‐based (160 kg plant‐available N per hectare). Soil–litter mixtures were incubated at 25 °C for 21 days. Sub‐samples were removed at 1, 7 and 21 days to determine the solubility and availability of P, As, Cu and Zn in soils. Results suggest that when litter was applied at 100 kg total P per hectare, contents of P, As, Cu and Zn were significantly greater in the soils amended with litter and granulated products than in the control (soil alone). However, the contents of P, As, Cu and Zn did not significantly differ in the soils amended with either normal litter or granulated litter products at total P or plant‐available N‐based application rates. This suggests that poultry litter granulation is a sound management practice that can be used to reduce concerns with fresh litter transport and potentially improve P and trace element balances in intensive poultry production regions, especially when applied on a plant‐available N basis.     

Land Application of Manure Can Influence Earthworm Activity and Soil Phosphorus Distribution

Earthworms can influence incorporation of animal manures and composts into the soil. As this activity can decrease the potential for phosphorus (P) loss in runoff and increase plant nutrient availability, we evaluated the effect of manure application on earthworm activity. Earthworm activity (as indicated by surface casts of Lumbricus terrestris) and soil P distribution were determined as a function of superphosphate, manure, and compost (dairy and poultry) applied at rates of 0, 50, 100, and 200 kg P ha^–1 yr^–1. Surface earthworm cast production was greatest in the wet and warm months of May to July. For instance, average annual cast production was 24,520 and 13,760 kg ha^–1 with respective applications of dairy manure and compost (100 kg P ha^–1) compared with 9,090 kg ha^–1 when superphosphate was added. This increased activity was accompanied by lower Mehlich 3 P (130 mg kg^–1) at the surface (0–5 cm) of soils treated with 100 kg P ha^–1 yr^–1 dairy manure than those treated with superphosphate (210 mg kg^–1) but greater concentrations at 5 to 10 cm deep (95 and 50 mg kg^–1, respectively). While there may have been greater downward movement of organic P added in manure and compost, the stimulation of L. terrestris activity by application of manure or compost has the potential to redistribute surface-applied P within the soil profile to a greater extent than when equivalent applications of P are made in the form of inorganic fertilizer.     

粪肥添加明矾对降低农田磷和重金属流失的作用

施用粪肥引起农田氮、磷流失的增加已引起人们广泛的关注。为了解粪肥中添加明矾可否降低农田污染物的流失,采用化学分析与田间试验相结合的方法研究了添加明矾对粪肥中水溶性养分和重金属浓度及施粪肥后农田养分、重金属流失的影响。结果表明,粪肥中添加明矾可大大降低其中的水溶性P和重金属浓度,其中水溶性P的下降幅度达79.3%。添加明矾后,粪肥施入农田形成的径流中P和重金属浓度明显低于不添加明矾的处理。但添加明矾对农田可溶性总N、NO3-N和NH4-N流失的影响不大。粪肥中添加明矾不会引起地表径流中铝浓度明显增加,对蔬菜产量影响不明显。     

紫色土坡耕地施肥水平对土壤侵蚀及氮磷流失影响

以紫色土坡耕地"冬小麦-夏玉米"种植模式为研究对象,设置对照处理、复合施用农家肥和化肥、单施化肥、单施化肥增加施肥量、单施化肥横坡垄作5种施肥水平,采用径流小区定点监测的方法,研究紫色土坡耕地不同施肥水平下土壤侵蚀特征。结果表明:施肥水平和降雨量对径流量影响极为显著,各施肥水平下次降雨泥沙流失量与降雨量呈线性正相关,单位面积泥沙流失量与径流量在增加施肥时为幂函数关系,其他施肥水平下均为对数函数关系。施肥水平和降雨量对径流中氮磷浓度均具有显著影响。各施肥水平下径流中氮磷流失浓度变化趋势与降雨量变化趋势基本一致,随降雨量增加而增大,不同施肥水平下,氮磷浓度波动范围不同;复合施用农家肥和化肥,径流中氮素及可溶性磷浓度较稳定;各施肥水平下径流中氮磷浓度最高值出现与暴雨事件出现基本一致,同时追加施肥等农事活动也对磷素浓度最大值具有一定影响。     

有机养分替代对小麦产量、土壤肥力及麦田氮磷径流流失的影响

为探讨不同有机肥替代率对小麦减肥增效及减少麦田氮磷流失的效果,在等氮有机养分替代条件下进行田间小区监测试验,设置8种不同处理,分别为空白对照(CK),常规施肥(CF),100%、50%、30%猪粪有机养分替代氮肥(M1、M2、M3)及100%、50%、30%秸秆有机养分替代氮肥(F1、F2、F3),研究有机肥替代率对小麦产量、麦田氮磷流失、肥料利用率和土壤肥力的影响。结果表明,100%有机养分替代处理与常规施肥处理相比小麦产量均显著降低,但减少了麦田氮径流流失,提高了土壤肥力。麦田不同处理下总氮流失量为21.90~33.66 kg·hm^-2,与常规施肥处理相比,不同比例猪粪、秸秆有机养分替代处理总氮流失量减少了8.44%~25.94%;总磷流失量为0.60~2.00 kg·hm^-2,100%有机养分替代处理相比于常规处理总磷流失量升高了24.64%~44.93%。不同处理下小麦氮、磷肥利用率分别为17%~35%、5%~19%,其中30%~50%猪粪有机养分替代处理下氮、磷肥利用率较高,而100%猪粪、秸秆有机养分替代氮、磷肥利用率较常规施肥处理均显著降低。有机养分替代能够缓解土壤酸化,使土壤pH值维持稳定,与常规施肥处理相比,有机养分替代处理下土壤肥力有所提高。综合不同比例猪粪、秸秆有机养分替代对小麦产量、土壤肥力及麦田氮磷径流流失的影响,30%~50%猪粪有机养分替代在保证小麦高产稳产的同时,能有效降低麦田氮径流流失量,且维持较低水平磷径流流失量,是一种适宜的资源有效利用、节肥增效的有机养分替代模式。本研究结果为小麦生产中合理利用养分资源、减少化肥投入、控制麦田氮磷径流流失提供了参考。     

施肥对北京山区农田地表氮磷流失的影响——以密云水库流域为例

农田非点源污染是最普遍的非点源污染类型之一,直接威胁北京市密云水库的水质状况;施用化肥是农田非点源污染物的主要来源.以北京市山区的农田化肥施用现状为基础,紧邻密云水库布设径流试验小区,种植当地的主要作物——夏玉米,设置常规(施肥)和对照(不施肥)2种处理,分析天然降雨条件下,施肥对农田地表氮和磷流失的影响.结果表明:施肥显著提高地表径流中氨态氮的浓度,但对径流硝态氮、总氮、可溶磷和总磷的影响有限;附着于泥沙上的颗粒态磷质量分数因施肥显著增加,但颗粒态氮质量分数仅在底肥施用后的首次产流中,表现出较大差异;泥沙是地表径流中氮和磷流失的主要载体,试验期间常规和对照小区,氮随泥沙流失负荷分别占氮流失总量的58.6％和53.6％,磷随泥沙流失负荷占比分别为97.2％和96.5％.研究结果可为密云水库流域农业生产管理和非点源污染治理提供参考.     

Effect Of The Sequential Application Of Liquid Organic Manure And Phosphorus On Maize Agronomic Traits And P Uptake In Some Tropical Soils

Improving phosphorus (P) fertility is challenging in tropical soils because of the fixation of P by soil components. The trial investigated the effect of the sequential application of poultry manure extract (tea) and P fertilizer on maize agronomy and P uptake, through screen house and field experiments. Results indicated that poultry manure tea is rich in nutrients but low in P and could be applied with phosphorus fertilizer to enhance P availability and reduce fixation. Application of P before manure tea produced taller maize plant on the field and the highest P uptake in the screen house and on the field. Manure tea also increased maize dry matter and grain yield. Combined application of poultry manure tea and P fertilizer had positive complementary and synergistic effects. It was concluded that manure tea enhances P availability and reduces P fixation by soil aluminum (Al) and iron (Fe) oxides irrespective of the sequence of application.     

水肥综合管理对减少滇池北岸韭菜地氮磷流失的研究

农田氮、磷随地表径流向水体迁移,不仅造成化肥利用率降低,农业生产成本上升,还对水环境造成污染,引起水体富营养化。针对滇池流域规模化韭菜生产施肥量大,农业面源污染严重等问题,采用田间试验,结合自然降雨与人工模拟降雨,研究了不同施肥及田间沟渠利用方式下农田氮、磷的流失风险。结果表明,相对于化肥表施,合理的有机-无机肥料配合施用以及化肥深施,可分别降低地表径流中总氮和总磷平均浓度53％和39％。施肥后1周为氮、磷流失的高风险期,随后其风险随时间延长而降低;通过小区问沟渠的改造,提高排水溢流口高度,控制径流在沟渠内滞留时间以及采用农田养分循环利用的回灌技术,可减少农田向环境水体输出总径流量的76％以上,并同时提高了肥料利用率。     

Sediment and phosphorus transfer in overland flow from a maize field receiving manure

Abstract. The transfer of suspended sediment (SS) and phosphorus (P) in overland flow from 30 m² field plots receiving either nil, surface‐applied or incorporated manure (slurry) were monitored to determine the vulnerability of land cropped to continuous forage maize to diffuse pollutant transfer in winter runoff. In the absence of slurry, P export was dominated by particulate forms, with up to 1 t SS ha^?1 and 0.75 kg total P ha^?1 collected from an individual storm event. Background concentrations of P in soluble (<0.45 μm) form were large (c. 0.5 mg L^?1) by eutrophication standards due to the previous build‐up of soil P, and largely independent of SS concentrations. Largest P exports (representing up to 23% of the slurry P applied) were measured when dairy slurry (3–13% dry solids) was surface‐applied. The P mobilized from the slurry accounted for up to 60% of total plot P export, with the majority occurring in a soluble bioavailable form during the first storm event. Initial P concentrations in runoff were in proportion to the amount of slurry P applied and significantly lower where rainfall was delayed after application. In one year, splitting the slurry application (3 × 10 kg ha^?1) reduced total P export by 25% compared to a single surface application (30 kg P ha^?1). In two years, incorporation of slurry, either by ploughing, or by tine cultivation, reduced the amount of overland flow by 50%, and the amount of P export by up to 60%, compared to the surface‐applied slurry treatments. Timeliness of slurry spreading to avoid periods of wet weather and simple cultivation of maize fields after harvest are practical and effective options to minimize SS and P transfer in land runoff from maize fields. The results also draw attention to the need to grow maize, and apply slurry to fields with a low P loss risk.     

Long-Term Dynamics of Labile and Stable Phosphorus Following Poultry Litter Application to Pasture Soils

A major source of runoff phosphorus (P) from agricultural soils is land-applied animal manure. Our work reports P levels in pasture soils in northern Alabama affected by long-term (0–20 years) application of poultry litter (PL). Sequential fractionation revealed different buildup patterns of labile and stable P fractions in these soils. Phosphorus built up in subsurface (20–40 cm and 40–60 cm deep) soils with lower application rates than P accumulated in surface (0–20 cm deep) soils, indicating a greater potential for surface runoff than leaching from these pasture fields. Correlation analysis of the surface soils showed levels of stable P extractable by sodium hydroxide (NaOH) were related to the cumulative amount of PL applied. The level of water-extractable P increased because PL application was significantly related to the number of years the soil receiving PL, not the annual application rate or the cumulative amount of PL applied.     

Corn and soybean grain yield responses to soil amendments and cover crop in upland soils

A field study was conducted on upland soils for six years to determine interactive effects of winter wheat (Triticum aestivum L.) cover crop, organic and inorganic soil amendments on grain yields and nutrient utilizations in a no-till corn (Zea mays)-soybean (Glycine max) rotation. Experimental design was a split-plot arrangement with four replicates. Cover crops were the main plots and fertilization treatments used as sub-plot. Fertilization treatments included an unfertilized control, poultry litter, poultry litter (PL) plus flue gas desulfurization (FGD) gypsum and inorganic N fertilizer applied every other year to corn. Corn grain yield and grain N and P uptake were greater with PL than inorganic fertilizer in 2014 and 2016. Addition of FGD gypsum to PL significantly increased corn grain yield by 15% in 2016. Cover crop increased corn and soybean grain yields in a year with less seasonal rainfall possibly by conserving soil moisture.     

Soil Properties and Macro Cations Status impacted by Long‐Term Applied Poultry Litter

Abstract

Most ethnic populations worldwide consume poultry products. Whereas poultry litter (PL) is a traditionally inexpensive and effective fertilizer to improve soil quality and agricultural productivity, overapplication to soils has raised concerns because excess nutrients in runoff could accelerate the eutrophication of fresh bodies of water. A long‐term field experiment of land application of PL to soils used for pasture growth has been maintained for nearly two decades in the Sand Mountain region of north Alabama, USA. In this work, several soil parameters impacted by the long‐term applied litter were characterized. The findings clearly support previous general observations that long‐term applied litter on pasture soils altered soil properties and macrocation levels. Unlike other studies, however, the effects of applied litter at multiple rates and years were examined, thus revealing the dynamic impacts on soil properties. Hay yields increased with the increase of years of PL application, regardless of the applied rate. This observation was consistent with previous observations that the labile phosphorus (P) portion in these soils increases with application years whereas total P increases with the cumulative applied PL amounts. Poultry litter application did not markedly affect soil electric conductivity, bulk density, or sodium (Na) or potassium (K) levels, especially at the soil surface (0–20 cm). Soil pH, carbon (C), C/nitrogen (N) ratio, calcium (Ca), and magnesium (Mg) were profoundly affected at all three soil depths (0–20, 20–40, and 40–60 cm). Most soil parameters analyzed in this study reached peak values with 10–15 years of applied litter. This observation suggests that there was a turning point of impact for applied litter around 10 years: prior to that the soil macrocations were altered positively as a result of accumulative functions. Continuous litter application may negatively alter a soil's capacity to retain macrocations, leading to less impact observed in this study. In other words, pasture soils with more than 10 years of applied litter would have higher potential for leaching and runoff. Our observation suggested that best management practices for land application of PL should take into consideration the different effects of PL application history.