Liquid Manure Application Research Articles

Nitrogen turnover and N2O production in incubated soils after receiving field applications of liquid manure and nitrification inhibitors

Applying abundant manure to soils can accelerate nitrogen (N) transformations and nitrous oxide (N2O) emissions. We conducted a laboratory incubation to examine the turnover of labile N in manured soils. Soils were collected from agricultural fields that had recently received spring-injected liquid dairy manure with or without admixing nitrification inhibitors. Bands and interbands of the manure plots were incubated separately. Time courses of ammonium (NH4+) and nitrate (NO3−) were used to derive and contrast zero-, first-, and second-order kinetics models. We found that nitrification rates were consistently better represented by first-order kinetics (k1). Furthermore, across all evaluated soils, the dependency of nitrification rate (k1 of NH4+) on initial NH4+ concentration was modelled by Michaelis–Menten kinetics reasonably well, with an affinity (Km) of 63 mg N·kg−1 soil (R2 = 0.82). Compared with the manure interbands, the initially NH4-enriched bands had a much faster nitrification rate, with half-life for NH4+ of only 4 d and rapid k1 (0.186 versus 0.011 d−1). Soil N substrate and k1 exerted control on N2O production. Nitrous oxide production increased linearly with both measured NH4+ intensity (R2 = 0.47) and modelled k1–NH4+ (R2 = 0.48). Conversely, N2O production increased non-linearly with NO3− intensity (R2 = 0.68), where high NO3− caused a saturation plateau with a threshold of 96 mg N·kg−1·d−1 — beyond which no additional N2O was produced. During peak N transformations, measured N2O-N flux was 1.4% ± 0.3% of the inorganic N undergoing nitrification. Heavily manured soils exhibited augmented N turnover that increased N2O fluxes, but inhibitors reduced these emissions by half.

Calculation of NH3 Emissions, Evaluation of Backward Lagrangian Stochastic Dispersion Model and Aerodynamic Gradient Method

Two campaigns measuring ammonia (NH3) emissions with different measurement techniques were performed on a large grass field (26 ha) after the application of liquid animal manure. The aim was to compare emissions from a confined area estimated from either (i) concentration measurements, both point and line-integrated measurements, combined with backward Lagrangian stochastic (bLS) dispersion modeling or by (ii) estimation of the vertical flux by the aerodynamic gradient method (AGM) with and without footprint correction approximated by the bLS model estimates of the flux footprint. The objective of the comparison is to establish the best practice to derive NH3 emissions from a large field. NH3 emissions derived from bLS agreed well when comparing point and line-integrated measurements. Simple point measurements combined with bLS yield good emission estimations for the confined area. Without footprint correction, the AGM underestimates the emissions by up to 9% compared to the footprint-corrected AGM results. The sensitivity of the measurement methods makes it possible to quantify NH3 emissions with diurnal patterns even five days after a field application of liquid animal manure under wet conditions. The bLS model proves to be a strong tool to determine the NH3 emissions from point concentration measurements inside a large field after a slurry application.

Biota of subtropical Oxisols under no-tillage with application of liquid cattle manure

Context Organic amendments in agricultural systems benefit the soil biota; however, their consecutive use can interfere negatively with the biota diversity and functionality. Aims This study evaluated the biomass and microbial activity and the epiedaphic fauna response of soil with consecutive liquid cattle manure (LCM) addition (4 years) in no-tillage. Methods The experiment was run in two Oxisol textures: sandy clay loam and clayey. The treatments were the control (un-manured) and three LCM doses: 60, 120 and 180 m−3 ha−1 year−1, distributed in a completely randomised block design with four replications. Microbial biomass carbon (MBC), soil microbial respiration (SMR), and microbial quotient (qMIC) were performed in the 0–5 cm layer. The epiedaphic fauna was captured by traps and abundance and ecological indices were evaluated in spring and autumn seasons. Key results In sandy clay loam soil, the MBC and SMR increased up to 180 m−3 ha−1 year−1 in both spring and autumn, while in clayey soil, only the SMR increased up in the spring. The most representative groups of the epiedaphic fauna were Collembola, Acarine, Coleoptera, and Hymenoptera. The Collembola population was predominant in both soils and seasons. Conclusions Consecutive annual applications of LCM in no-tillage had a greater positive impact in the soil biota in the sandy clay loam soil and in the spring season and did not negatively affect the ecological functioning of the soil biota system. Implications Application of liquid cattle manure may be beneficial for the sustainability of the agroecosystem and as a highly available and low-cost waste, it may be an alternative for replacing chemical fertilisers.

Effect of biofertilizer, liquid organic manures along with inorganic fertilizers on economic yield of okra (Abelmoschus esculentus L. Moench)

An experiment was conducted at Department of Horticulture, Vasantrao Naik Marathwada Krishi Vidyapeeth, Parbhani, during kharif 2019 to study the effect of biofertilizer, liquid organic manures viz., Panchagavya, Vermiwash, Jeevamrit and Cow urine on economic yield of okra in the open field condition. The experiment was laid in Randomized Block Design with fifteen treatments replicated twice by using the variety Parbhani Kranti. The various types of liquid organic solutions prepared from plant and animal origin are effective in promotion of growth and increasing yield in okra. Different concentration of liquid organic manures like Panchagavya (500 lit/ha), Vermiwash (100 lit/ha) and Cow urine (100 lit/ha) were given at 15, 45 and 75 DAS through foliar spray and Jeevamrit (500 lit/ha) and biofertilizer like Azospirillium (2.5 lit/ha) was applied through drenching at 15, 45 and 75 DAS along with Recommended dose of fertilizers (N:P:K::100:50:50]. The observations on yield parameters were recorded during the investigation. On the basis of observations recorded, the result of the present investigation revealed that, combined application of different organic liquid manures along with recommended dose of fertilizer has significant effect on economic yield of okra as compared to RDF alone. The yield parameter like weight of fruit (14.15 g), length of fruit (12.97 cm), diameter of fruit (14.81 mm), number of fruit per plant (20.73), fruit yield per plant (293.32 g) and fruit yield per ha (162.95 q/ha) were significantly superior in the treatment T14 [RDF + Jeevamrit + Vermiwash + Panchagavya] and it was found to be significantly superior over other treatments and gives best results as compared to Control (100:50:50 N:P:K kg/ha).

Spatial distribution and temporal change of antibiotics in soils amended with manure using two field application methods

Compared to surface application, manure subsurface injection significantly reduces transport of manure-associated antibiotics via surface runoff. However, the environmental fate of antibiotics in manure injection slits is unknown. A field investigation was conducted to monitor distribution and dissipation of pirlimycin, tylosin, chlortetracycline, and sulfamerazine in soil following either surface application or subsurface injection of liquid dairy manure. A simulated rainfall was conducted on days 0, 3, and 7 after manure application. Soil samples were collected before, on the day of, and 5, 14, 60, and 180 days after the simulated rainfall. Around an hour after manure application, antibiotic concentrations in injection slits were 4–49 and 4–26 times higher than those outside the slits and in surface application plots, respectively. Antibiotics concentrated in the injection slits for an extended time with limited horizontal and vertical movement, exposing the microbial community inside the slits to an elevated level of antibiotics. Dissipation of antibiotics was the fastest during the first 14 d after manure application before slowing down. There were no significant differences in antibiotic dissipation patterns in soils amended with manure using two application methods. Although the half-lives ranged from 3‐11 d for pirlimycin, 3–10 d for sulfamerazine, 5–12 d for tylosin, and 3–21 day for chlortetracycline; pirlimycin, sulfamerazine, and tylosin remained detectable in soil even 180 d after the single manure application, indicating that soils could be a long-term source for antibiotics to the surrounding environment. Overall, in addition to resulting in less surface runoff of antibiotics from the fields, manure subsurface injection can also retain antibiotics in the injection slits and limit their movement overtime. However, more studies are needed to better understand if elevated levels of antibiotics, nutrients, organic matter, and water would result in “hot zones” for antibiotic resistance development in the manure subsurface injected fields.

Characteristics of veterinary antibiotics in intensive livestock farming watersheds with different liquid manure application programs using UHPLC-q-orbitrap HRMS combined with on-line SPE

Composted livestock manures, in both solid and liquid form, are used as fertilizers in cropland. However, excess solid and liquid manures in agricultural watersheds are considered as nonpoint pollution sources because of their high nutrient and heavy metal contents of, as well as their antibiotic contents, especially veterinary antibiotics (VAs). In this study, 21 VAs under nine classes (i.e., cephems, ionophores, lincosamides, penicillins, pleuromutilins, quinolones, streptogramins, sulfonamides, and tetracyclines) found in agricultural watersheds were simultaneously analyzed via UHPLC-q-orbitrap high-resolution mass spectrometry using an on-line solid-phase extraction system. The residues of VAs in the surface water of two intensive livestock rearing watersheds (Cheongmi and Gwangcheon streams) in Korea were successfully quantified, and the values were found to range from 1.84 ± 0.42 ng L−1 to 835.6 ± 31.9 ng L−1. Time lags of 2–3 months were observed between the periods of liquid manure application and the periods with the maximum concentrations of VAs. In both watersheds, samples from points close to areas with extensive application of liquid manure exhibited high concentrations of most of the 21 VAs. Between the watersheds, the one with heavier application of liquid manure showed higher concentrations of the target VAs. To the best of our knowledge, this study represents the first attempt at evaluating the correlation between liquid manure application and environmental occurrence of VAs in surface water. The findings reveal that liquid manure application plays an important role in introducing VAs into aquatic environments.

Responses of Soil Microbial Activity to Swine Manure Applications

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

Liquid Cattle Manure Effect on Corn Yield and Nutrients’ Uptake and Soil Fertility, in Comparison to the Common and Recommended Inorganic Fertilization

Liquid dairy cattle (Bos taurus) manure effect on corn (Zea mays L.) yield and nutrients’ uptake and soil fertility were studied, in comparison to the crop’s common and recommended inorganic fertilization, by means of a 5-year field experiment. The treatments applied each year in the same plots were: (i) manure, (ii) common inorganic fertilization, (iii) recommended inorganic fertilization, and (iv) no fertilization. Each year from each plot, surface soil samples were collected before sowing, corn aboveground biomass was collected at silage, they were analyzed, and grain yield was determined at harvest. Upon all kinds of fertilization, corn silage yield increased in comparison to control and ranged between 51 and 194, 50 and 190, and 39 and 189% for the manure, recommended, and common inorganic fertilization treatment, respectively. Similarly, grain yield and the macro- and micronutrients’ plant uptake were increased. Soil fertility improved regarding the NO3-N, which upon organic or inorganic fertilization increased 10–46% in comparison to the control. Manure application significantly increased K by 32–81%. However, in the case of P, an excessive increase was observed, which was two to three times higher than the inorganic fertilization (30–44 mg kg−1). Consequently, repeated annual applications of liquid cattle manure to soil can enhance crop yield, nutrients’ uptake, and soil fertility, at levels higher or similar to the common or recommended inorganic fertilization for the crop. However, the possibility of P build up should also be considered.

Evaluation of the Crop Yield and Nutrient Balance by Application of Liquid Manure in Paddy Soil

The purpose of this study was to evaluate the effects of liquid manure to increase the yield of green manure in winter season, and to investigate the effect of green manure incorporation to increase the yield of maize grain and nutrient balance improvement in upland soil. The green manure used in this experiment was barley and hairy vetch with a mixed ratio of barley and hairy vetch (75:25), respectively. Liquid manure applied 0, 26, 52, 78, and 104 Mg ha-1, respectively, and the half of the total amount was applied as basal fertilizer, and the other half was topdressing. Nitrogen inputs through liquid manure were 0, 7.1, 15.6, 21.5 and 28.4 kg ha-1, respectively, and the phosphorus inputs were 0, 11.3, 22.6, 33.9 and 45.2 kg ha-1, respectively. The yield of green manure crops increased significantly with the increase of liquid manure application, but the yield of hairy vetch decreased. In the summer season, the green manure crops were incorporated, and the compost was used in the conventional treatment. The yield of maize grain increased with increasing green manure yield. The yield of maize grain of green manure crops incorporation treatments was up to 81% compared to conventional cultivation treatment, however the two-year experiments showed an increase on maize grain yields in green manure incorporation treatment. In addition, the incorporation of green manure crops greatly improved the phosphorus balance in compared to conventional cultivation. Therefore, productivity improvement of green manure crops by utilizing liquid manure is thought to have significantly contributed to the improvement of maize grain yield and nutrient balance. The effect of green manure incorporation on the maize grain yield with different rate of liquid manure application for two years. The maize grain yield of PM4 treatment was 759 kg 10a-1, and up to 81% in compared with the NPK treatment in 2017. However, the maize yield of incorporation green manure treatment in 2017 tended to increase in compared with that of in 2016.

Utilization of liquid pig manure for resource cycling agriculture in rice-green manure crop rotation in South Korea.

A 2-year field experiment was carried out on rice (Oryza sativa, Japonica type) cultivation in South Korea. The objective of this study was to investigate the effect of application of liquid pig manure on biomass production and nutrient supply of green barley (Hordeum vulgare L.) and hairy vetch (Vicia villosa Roth) green manure crops and to evaluate the effect of nutrients supplied from these sources on rice yield and soil quality in a rice-green manure crop rotation system. Over the 2-year study period, application of liquid pig manure increased biomass production of green manure crops of barley and hairy vetch by more than 216% and 135%, respectively, compared with without liquid pig manure. Moreover, the results showed that the application of liquid pig manure significantly increased the nutrient supply levels in green barley- and hairy vetch-treated areas. Positive effects related to nutrient supply in green barley and hairy vetch treated with liquid pig manure were observed on rice yield, soil chemical characteristics, and microbial biomass C and N contents. In conclusion, the addition of liquid pig manure systems using green manure crops of green barley and hairy vetch improved rice productivity and soil quality. It is suggested that these combinations can be effective in developing resource cycling agriculture in a rice-green manure crop rotation system as it reduces the need for inorganic fertilizer.

Ammonia emission measurement with an online wind tunnel system for evaluation of manure application techniques

Abstract Field application of liquid manure contributes substantially to atmospheric ammonia. Low emission application methods are commonly used to reduce ammonia transfer to the atmosphere. To document which application method results in lower ammonia volatilization there is a need for high precision measurements to ensure that small differences in total emission and emission patterns can be quantified. This paper presents the evaluation and application of a new system of dynamic chambers (wind tunnels) with online cavity ring down spectroscopy measurements of ammonia. The system allows for high time resolution of 104 min throughout the measuring period (≥90 h) when testing two treatments and one reference in triplicates. Measurement variability is low with a coefficient of variation of 13 ± 8% within triplicates. The system was used to investigate the effect of trailing shoes compared to trailing hoses on different soil and crop types, where the expected differences in ammonia volatilization are low. The results show that when applying pig slurry on coarse sand a significant reduction of 47 ± 20% was obtained, whereas the reduction when applied on loamy sand and sandy loam was lower and occasionally insignificant. During ten experiments on three different soil types, an overall average reduction of ammonia volatilization from using trailing shoes compared to trailing hoses was found to be 19 ± 12%. Furthermore, the importance of correct use of trailing hoses was examined by comparing with application above the crop canopy. Application at the ground surface gave an ammonia emission reduction of 40 ± 13% compared to application 20 cm above the canopy.

Impact of liquid hog manure applications on antibiotic resistance genes concentration in soil and drainage water in field crops.

Agricultural practices such as manure applications could contribute to the spread of antibiotic resistance genes (ARGs) within the environment. Our objective was to assess the impact of certain fertilization methods (mineral or manure) and tillage practices (reduced or conventional) on the presence of ARGs and bacteria in soil and drainage water under wheat and grain corn crops. Targeted ARGs tet(T), sul1, and blaCTX-M-1 in liquid hog manure, soil, and water samples were quantified by qPCR. Conventional PCR was used to detect mcr-1 and mcr-2. ARGs in control plots were detected despite the absence of manure, representing an environmental reservoir of resistant microorganisms. The manure application rate higher than 39 m3/ha increased tet(T) and sul1 gene concentrations in soil for more than 180 days. Tillage practices had no impact on ARG concentrations in soil and water samples. The blaCTX-M-1 gene was only detected in seven water samples in 2016, but no link was established with the treatments. The mcr-1 and mcr-2 genes were not detected in all tested samples. This study demonstrated that tet(T) and sul1 gene concentrations increased in soil after liquid hog manure application as well as in drainage water in the next weeks.

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

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

Legacy effects of liquid dairy manure in grain production systems

Transferring liquid manure from dairy farms to nearby cash-grain farms has the potential to support high grain yields at reduced cost, while making use of animal wastes that might otherwise cause environmental hazards if not utilized appropriately. Yet, empirical evidence of the legacy of long-term liquid manure application, and its interaction with crop rotation management on grain yield and soil properties is scarce. Here we evaluate the benefits and legacy of repeated liquid dairy manure (115 Mg ha−1 yr−1) over 12 years (2003–2014) on corn yield, soil organic matter (SOM) content, and soil nutrient availability in three annual cash grain cropping systems under different crop rotation management in southern Wisconsin. The three systems include: continuous corn (CC); minimum-till corn-soybean (CS); and an organically managed corn-soybean-wheat/oat-clover rotation (CSW). Results showed that, liquid manure application increased corn yield, soil test phosphorus (STP), and soil test potassium (STK) content across the three systems, and soil pH and nitrate (0–90 cm) in CC over the 12 years. The lack of significant impact of manure on SOM content suggested that the liquid manure application was insufficient to build SOM on these fertile Mollisols. The legacy benefit of liquid manure application on corn yield was significant in 2015, but no longer detectable in 2017, three years after the last application, while STP and STK content remained higher in manure treated plots than no manure plots. In 2017, cation exchange capacity (CEC), soil pH, and soil nitrate content were also greater in manured plots, but the effect was crop rotation specific. We show that manure is an equivalent or superior substitute for synthetic fertilizers providing a potential win-win scenario for both grain and dairy farms in the North Central US, where synthetic fertilizer is costly (cash-grain farms) and land for manure spreading is often limited (dairy farms). Our study suggest that liquid dairy manure application is beneficial for agroecosystem productivity but continual applications are needed to sustain its benefit in the crop production systems in the region.

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

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

Long‐term surface application of dairy liquid manure to soil under no‐till improves carbon and nitrogen stocks

AbstractManure application and no‐till management improve soil quality, crop yields and C inputs, but little specific knowledge is available regarding the combined effect of long‐term dairy liquid manure (DLM) application and no‐till management on soil organic matter status and soil structure in topsoils. Here, we assess the impacts of surface‐applied DLM for a 10‐year period on soil total organic carbon (TOC) and nitrogen (TN) concentrations and stocks, on organic matter fractions and on soil physical‐structural attributes in a no‐till crop rotation system on clayey Ferralsol under no‐till crop rotation management in a subtropical climate. Four rates of DLM (0, 60, 120 and 180 m3 ha−1 year−1) were applied in a randomized block design with four replications. Soil samples were collected to calculate TOC and TN stocks to 100‐cm depth and organic matter fractions in the 0–5‐cm layer, and physical indicators of soil quality: bulk density, macroporosity and microporosity and aggregate stability. The largest DLM rates (120 and 180 m3 ha−1 year−1) added 3.8–5.8 Mg C ha−1 year−1 as manure, increased crop residue input by 0.6 Mg C ha−1 year−1, and increased TOC stock by 17% and TN stock by 27% in the top 10 cm of soil, at annual accumulation rates that averaged 0.72 Mg C ha−1 year−1 and 86 kg N ha−1 year−1. Stocks of TOC and TN in the sand‐POM (particulate organic matter) fraction under the 180 m3 ha−1 year−1 rate increased by 49 and 63%, and in the silt‐MOM (mineral‐associated organic matter) fraction by 30 and 47%, respectively. In the clay‐MOM fraction, the change in TOC was not significant, but the TN increased by 16%. Soil physical‐structural attributes (bulk density, porosity and aggregates) were improved by DLM application in the 10‐cm layer and followed the soil carbon and nitrogen increments. Overall, the DLM amendment applied on the soil surface of no‐till proved to be a strategy to ameliorate soil organic matter status, an important factor for agronomic and environmental benefits, besides improving crop biomass production.Highlights Long‐term application of liquid manure increased concentration and stock of SOC and TN in the 0–10‐cm layer. Increases of 0.72 Mg C ha−1 year−1 and 86 kg N ha−1 year−1 were observed in the 10‐cm topsoil with manure. SOC and TN increased in the sand‐POM and silt‐MOM size fractions but not the clay‐MOM fraction. Improvements to soil physical‐structural attributes were related to organic matter changes.

Ammonia Volatilization Losses during Irrigation of Liquid Animal Manure

Ammonia loss resulting from land application of liquid animal manure varies depending on the composition of the manure and the method used to apply manure to cropland. High levels of ammonia volatilization result in an economic loss to the farmer based on the value of the nitrogen and have also been shown to be a source of air pollution. Using irrigation as a method of applying liquid manure to cropland has generally been accepted as a method that increases the volatilization of ammonia. However, only three studies available in the literature measured the amount of ammonia lost during the irrigation process. Only one of the three studies concluded that ammonia loss during irrigation was significant. A pooled statistical and uncertainty analysis of the 55 available observations was performed to determine if ammonia loss occurred during irrigation of animal manure. Data on the total solids content of the manure were also included as an indicator of evaporation losses. Volatilization losses during irrigation were not found to be statistically significant, and evaporation losses were small, 2.4%, and agreed with previous studies on irrigation performance. Furthermore, the range of ammonia loss reported in previous studies was determined to be within the errors associated with the measurement of total ammoniacal nitrogen concentrations and the calculation of per cent differences.

Short-Term Effects of Solid and Liquid Manure Amendments on Microbial Activity of an Alkaline Soil with High Lime Content during Horticultural Plant Growing

ABSTRACTThis study aimed to determine the effects of solid and liquid manures on soil microbial status and activity in organic farming model under greenhouse conditions. Two different test plants, rocket (Eruca vesicaria) and lettuce (Lactuca sativa), were grown also to determine the effects of plant species on related traits of the soil. A greenhouse experiment was conducted in randomized complete blocks with three replicates. The experiment was consisted of treatments with and without plants and manure.The combined doses of solid and liquid manure in rocket and lettuce soils resulted in an increase by 142.09 and 105.49% in urease, 130.75 and 135.24% in alkaline phosphatase, 162.40 and 195.06% in β-glucosidase, 135.29 and 329.88% in dehydrogenase activities and 306.34 and 182.42% in number of bacteria, respectively, compared to the control without manure. Significant changes for each parameter were also observed according to plant species (increase ranging from 54 to 128.06%). Even though influence of plants was positive, it was not as effective as manure on the measured parameters. It was determined that, in general, stimulating effect of the combined application of solid and liquid manures on the enzyme activities and number of bacteria in soil is significantly higher than the plant-derived effects (plant type, root secretions, etc.).

Fall Tillage Reduced Nutrient Loads from Liquid Manure Application during the Freezing Season.

Reducing agricultural runoff is important year round, particularly on landscapes that receive wintertime applications of manure. No-tillage systems are typically associated with reduced runoff loads during the growing season, but surface roughness from fall tillage may aid infiltration on frozen soils by providing surface depressional storage. The timing of winter manure applications may also affect runoff, depending on snow and soil frost conditions. Therefore, the objective of this study was to evaluate runoff and nutrient loads during the freezing season from combinations of tillage and manure application timings. Six management treatments were tested in south-central Wisconsin during the winters of 2015-2016 and 2016-2017 with a complete factorial design: two tillage treatments (fall chisel plow vs. no-tillage) and three manure application timings (early December, late January, and unmanured). Nutrient loads from winter manure application were lower on chisel-plowed versus untilled soils during both monitoring years. Loads were also lower from manure applied to soils with less frost development. Wintertime manure applications pose a risk of surface nutrient losses, but fall tillage and timing applications to thawed soils can help reduce loads.

Damages of Young Persimmon Tree as Affected by Application of Immature Liquid Pig Manure

BACKGROUND: Liquid pig manure (LPM) has been used as an alternative for conventional fertilizers on some gramineous crops. However, its chemical properties varied widely depending on the degree of the digestion. A pot experiment was conducted to determine the responses of persimmon trees to immature (not well-digested) LPM application. METHODS AND RESULTS: Ten application levels of immature LPM, consisted of a total of 3 to 30 L in 3-L increment, were applied during summer to 5-year-old ‘Fuyu’ trees grown in 50-L pots. Increasing the LPM application rate caused defoliation, wilting, and chlorosis in leaves. When applied with the rate of 3 L during summer, the tree produced small fruits with low soluble solids and bore few flower buds the following season, indicating insufficient nutritional status. In trees applied with the LPM rates of 6∼12 L, both fruit characteristics and aboveground growth of the trees appeared normal but some roots were injured. However, application of higher LPM rates than 27 L resulted in small size, poor coloration, or flesh softening of the fruits the current season. Furthermore, the high LPM rates caused severe cold injury in shoots during winter and weak shoot growth the following season. It was noted that the application of higher LPM rate than 9 L damaged the root, even though above-ground parts of the tree appeared to grow normally. CONCLUSION: The results indicated that an excessive immature LPM application could cause various injuries on leaves, fruits, and the roots in both the current and the following season.