Manure-treated Plots Research Articles

105 Botanical composition, yield, horse preference, and forage and soil nutrient values of grass pastures treated with different soil amendments

Forage is the foundation of a horse's diet, therefore, pasture management is critical to improve horse health and pasture productivity. The objective of this study was to evaluate botanical composition, horse preference, yield, and forage and soil nutrient values of pasture treated with horse manure, horse compost, commercial urea fertilizer, and a no amendment control. Researchers hypothesized soil amendments would increase soil nutrients and yield with minimal effects on botanical composition, preference and forage nutrient value. Replicated (n = 3) plots of established cool-season mixed grass pasture were 3 × 6 m and located in St. Paul, Minnesota. The soil was a Waukegan silt loam with a pH of 6.4 and 47 g kg–1 organic matter. Urea was applied based on initial soil test recommendations, 0.64 cm of compost was applied based on common recommendations, and manure was applied at a rate to represent horse manure deposition in May 2022. Sample collection and grazing periods occurred in May, June, July, August, and October 2022, each over a 2-d period. Botanical composition, average forage height and maturity, soil samples, forage samples, and forage yield were taken immediately before grazing. Horses were allowed to graze all plots for 4 h with preference visuallyassessed at 2- and 4 h post-grazing based on percent removal. Data were analyzed as a randomized complete block design using PROC MIXED in SAS with significance set at P ≤ 0.05. Season-long yield ranged from 2,690 to 3,363 kg DM ha-1 and did not differ across treatments (P > 0.05). Botanical composition differed across treatments with the control having the most weeds (32%) and the least amount of grass (62%) while manure treatments resulted in the most bare ground (11%; P ≤ 0.05). The soil nutrients magnesium and phosphate were highest in compost-treated plots and nitrate-nitrogen and sodium were highest in manure-treated plots (P ≤ 0.05). Forage nutrient content did not differ across treatments (P > 0.05). Horses did not prefer pasture treated with manure and only 15 and 33% of forage was consumed after 2 and 4 h, respectively (P ≤ 0.001). All other treatments averaged 53 and 78% removal after 2 and 4 h, respectively. Based on differences observed in botanical composition and horse preference, commercial fertilizer and compost appear to be the most beneficial soil amendments for horse pastures.

Biochar and Manure Applications Differentially Altered the Class 1 Integrons, Antimicrobial Resistance, and Gene Cassettes Diversity in Paddy Soils.

Integrons are genetic components that are critically involved in bacterial evolution and antimicrobial resistance by assisting in the propagation and expression of gene cassettes. In recent decades, biochar has been introduced as a fertilizer to enhance physiochemical properties and crop yield of soil, while manure has been used as a fertilizer for centuries. The current study aimed to investigate the impact of biochar, manure, and a combination of biochar and manure on integrons, their gene cassettes, and relative antimicrobial resistance in paddy soil. Field experiments revealed class 1 (CL1) integrons were prevalent in all samples, with higher concentration and abundance in manure-treated plots than in biochar-treated ones. The gene cassette arrays in the paddy featured a broad pool of cassettes with a total of 35% novel gene cassettes. A majority of gene cassettes encoded resistance to aminoglycosides, heat shock protein, heavy metals, pilus secretory proteins, and twin-arginine translocases (Tat), TatA, TatB, and TatC. Both in combination and solo treatments, the diversity of gene cassettes was increased in the manure-enriched soil, however, biochar reduced the gene cassettes’ diversity and their cassettes array. Manure considerably enhanced CL1 integrons abundance and antimicrobial resistance, whereas biochar amendments significantly reduced integrons and antimicrobial resistance. The results highlighted the differential effects of biochar and manure on integrons and its gene cassette arrays, showing increased abundance of integrons and antibiotic resistance upon manure application and decrease of the same with biochar. The use of biochar alone or in combination with manure could be a beneficial alternative to mitigate the spread of antimicrobial resistance and bacterial evolution in the environment, specifically in paddy soils.

The Residual Effect of Pre-Rice Green Manuring on a Succeeding Wheat Crop (Triticum aestivum L.) in the Rice-Wheat Cropping System in Banke, Nepal

Rice-wheat is the most widely used cropping pattern in Nepal. This cereal-based cropping system is highly nutrient exhaustive and unsustainable from a soil management perspective. They contribute neither nitrogen nor biomass to the soil. The net effect is the export of nutrients from the soil. The unused period between wheat harvest and rice transplanting is the summer fallow, and the incorporation of green manure during this short period increases the yield of both crops and improves the soils chemical properties. Altogether, there were 9 treatments and 3 replications with the randomized complete block design (RCBD). Dhaincha, sun hemp, black gram, cowpea, mung bean, and rice bean were used as pre-rice green manure. No chemical fertilizers were used for the green manure, and in wheat, 150 : 50 : 50 NPK kg/ha was applied. Goat manure was applied at the rate of 10 t/ha. The main objective of the study is to ascertain the residual effect of pre-rice green manuring on the chemical properties of the soil and the yield attributes of the succeeding wheat crops. The chemical properties of the soil were analyzed before and after the harvesting of wheat, and the yield attributes parameters were analyzed. The result showed that the green manure-treated plots gave a significantly higher yield as compared to solely chemical fertilizers-treated plots. The maximum grain yield was obtained from black gram (5.870 t/ha). There was a 39.76% increase in the grain yield in the black gram-incorporated plots as compared to the only-chemical fertilizers-treated plots. There was a highly (<0.001) significant difference in the soil organic matter of the green manure-treated plots and the only-chemical fertilizers-treated plots. The sun hemp-incorporated plot increased the soil organic matter by 71% when compared to the only-chemical fertilizers-treated plot. There was no significant residual effect of pre-rice green manuring on the soil pH in a one-cropping season. However, there was a significantly higher residual effect of the green manure on the soil’s total nitrogen content in all green manure-treated plots. It was found to be the highest (0.087%) in pre-rice dhaincha. The overall results indicate that the incorporation of pre-rice green manuring improved the soil’s chemical properties and increased the grain yield of the succeeding wheat crops in a rice-wheat cropping system.

Combined application of organic manure with urea does not alter the dominant biochemical pathway producing N2O from urea treated soil

Combined application of organic amendment with synthetic fertilizer is an emerging management technique for maximized agronomic benefits without drastic soil health effects. However, little attention has been paid to the environmental costs of such management as the primary focus has remained on agronomic outcomes. In present study, we investigated the impacts of three organic amendments including dairy cattle manure (20 t/ha), poultry manure (20 t/ha), and a biochar (30 t/ha) applied along with urea (55 kg-N/ha) on soil N2O fluxes and explored the mechanisms behind N2O emissions. Plots with urea-only application were used as a control. For source partitioning of soil-emitted N2O, we used isotopocule mapping approach. The results showed significantly higher N2O emission rates from manure-treated plots compared with biochar or control treatments plots. The cumulative N2O emissions rates for 125 days from control, biochar, dairy cattle, and poultry treatments were 0.76, 0.70, 0.96, and 1.05 kg N2O-N/ha, respectively. Isotopocule mapping approach revealed that bacterial denitrification was the dominant pathway for temporal high N2O emission events as the fractions of bacterial denitrification ranged between 0.5 and 0.9 among treatments. Soil DNA-based Q-PCR assays showed significant increase in abundance of NO2− reducing denitrifiers in dairy cattle and poultry treated plots suggesting acceleration in N2O emissions was due to shift in the molecular ratios of (nirS + nirK)/nosZ denitrifying bacterial community. In contrast to manure treatments, the combined application of biochar along fertilizer significantly improved soil C contents with a slight decrease in N2O emission rates. Therefore, biochar appeared to be the best option to minimize soil quality loss without additional environmental cost.

EFFECT OF LIQUID CATTLE MANURE ON SOIL CHEMICAL PROPERTIES AND CORN GROWTH IN NORTHERN GREECE

SUMMARYThe impact of liquid cattle (Bos taurusL.) manure, applied to soil at common rates and for several years, on certain plant parameters and soil properties has not been studied extensively. The objectives of this study were: a) to assess the effects of manure application on corn (Zea maysL.) yield, macro- and micronutrient concentrations and uptake, in a three-year (2006–2008) field experiment conducted in northern Greece and b) to evaluate the 11-year effect of manure application on soil fertility (particularly on micronutrients avialability) and chemical properties (especially on organic C and total N content). The field experiment of this study had been used in a similar fertilisation experiment since 1996. The treatments, which were applied on the same plots each year over the 11-year period, were: (i) soil incorporation of liquid dairy cattle manure before sowing, at a rate equal to the common N-P inorganic fertilisation for each crop (based on manure's total N and P content); (ii) application of the common inorganic N-P fertilisation for each crop before sowing; (iii) identical to ii, but with split application of the N fertilisers; (iv) no fertilisation (control). Corn dry aboveground biomass yield at the R3 growth stage and grain yield, N, P, K concentrations and macro- and micronutrients uptake increased (p≤ 0.05) upon manure addition at levels similar to or higher than the inorganic fertilisation treatments. The relative increase in grain yield during the three-year period ranged between 63–75% for manure treatment and 50–75% for both inorganic fertilisation treatments. After 11 years of manure application, organic C, total N, and available NO3-N, P, K, Cu, Zn, Mn, and B increased (p≤ 0.05) in the surface soil (0–30 cm). However, no trend of nutrient build up was evident through years (except for Zn). Surprisingly, salinity and available NO3-N in the 60–90 cm soil depth of the manure-treated plots were lower (p≤ 0.05) than that of the inorganic fertilisation treatments and similar to control. Electrical conductivity was 1.76, 3.05, 2.96 and 1.36 dS m−1, for manure treatment, the two inorganic fertilisation treatments and control, respectively, whereas the respective NO3-N concentrations were 7.7, 44.6, 55.1 and 8.3 mg kg−1. Conclusively, repeated application of liquid cattle manure into the soil, at rates comparable to the common inorganic fertilisation for 11 years, can enhance crop yield and macronutrient concentrations in plant tissues and uptake, at levels similar to the inorganic fertilisation. In addition, it can increase micronutrients plant uptake and maintain soil fertility with respect to both macro- and micronutrients and increase soil organic C and total N, without either causing nutrient build up or increasing soil salinity and NO3−accumulation in the deeper soil layers.

Wood ash effects on chemical and microbiological properties of digestate- and manure-amended soils

A field study was carried out to evaluate the potential of wood ash as a fertilizer in grassland systems in combination with enriched N organic wastes. Six treatments including manure or digestate, each combined with wood ash at 0, 1, and 3 t ha−1 were spread onto the soil to an amount equivalent to 120 kg N ha−1. Three soil samplings and one cutting was carried out within one growing season (3 months). A higher pH value was found in manure-treated plots, the pH rise being proportional to the amount of wood ash added. Those plots amended with digestate were characterized by a larger content of total C, NH4 +, and total P (TP) regardless of the amount of ashes. Microbial activity, assessed by basal respiration and microbial biomass carbon of the differently treated soils, was not affected neither by the nature of the organic waste nor by the amount of wood ash added. However, amending soil with digestate resulted in a more efficient soil microbial community, as shown by the lower values of the metabolic quotient. Such effects were accompanied by a higher percentage of plant cover, particularly of leguminous plants in digestate-treated plots. The time of sampling (seasonal effects) was found to influence the soil pH and electrical conductivity (EC), as well as the nutrient content (total N, NH4 +, and NO3 −). Overall, the combined use of wood ash and biogas digestate can constitute an efficient way for the disposal and recycling of both products and additionally, it may constitute an environmentally friendly alternative to mineral fertilizers for acid soils.

Changes in Microbial Biomass Parameters of a Heavy Metal‐Contaminated Calcareous Soil during a Field Remediation Experiment

Soil microbial biomass parameters give useful information about the restoration degree and quality of contaminated soils. These parameters were studied in a field experiment where the effect of two organic amendments on the bioavailability of heavy metals in an agricultural soil and on their accumulation in Beta vulgaris and Beta maritima was assessed. The soil was a calcareous Xeric Torriorthent and the total metal levels were (mg kg(-1)): 2706 Zn, 3235 Pb, and 39 Cu. The treatments were: fresh cow manure, olive husk, and inorganic fertilizer as a control. Two successive crops (B. vulgaris and B. maritima) were grown on the treated and untreated plots. The soil was sampled before each planting and after each harvest over a 15-mo period. Biomass C and N increased in all plots, especially in the organically amended ones. The ratio CO(2)-C/biomass C decreased in olive husk and manure-treated plots, in comparison with the control, and also during the experiment, suggesting a beneficial effect of the organic amendments. In olive husk-treated plots a significant increase in the ratio of biomass C/total organic carbon (TOC) with time was observed. This indicated a reduction of heavy metal stress on the microbial population. The amendments showed, in general, a beneficial effect on soil quality and fertility, while microbial biomass parameters were found to be useful indicators of the evolution of the remediation processes.

Responses of grassland soil nematodes and protozoa to multi-year and single-year applications of dairy manure slurry and fertilizer

In order to improve understanding of how long-term use of manure affects nitrogen cycling processes, the effects of multiple years of manure applications on abundance of protozoa and nematode community structure were assessed. Plots of a grass sward in the Fraser Valley of British Columbia were either left untreated or were treated with dairy manure slurry or fertilizer, each at 50 or 100 kg NH 4–N ha −1, two to four times per year for six consecutive years. Nematode community structure and protozoan abundance were determined at 19 sample dates during the fourth (1997), fifth (1998) and sixth (1999) years of application. Protozoa, bacterivorous nematodes and fungivorous nematodes were consistently more abundant in soil treated with manure at both rates than in fertilized and untreated soil, indicating that microbial turnover and flux of nutrients through the soil food web was enhanced in manured soil relative to fertilized or untreated soil. The Maturity Index (MI) and the MI2-5 were both reduced by fertilization and manure, relative to the control. The MI for the manure treatment was lower than for the fertilizer treatment as a result of greater relative abundance of enrichment opportunist nematodes in manure-treated soil. Accordingly, the MI2-5 did not differ between the manure and fertilizer treatments, suggesting that with the exception of enrichment opportunists fertilizer and manure have similar effects on structural complexity of the soil food web. Populations of micro-fauna were also assessed through 1998 and 1999 in subplots that had been treated with manure or fertilizer for four years and stopped receiving manure or fertilizer in 1998, and in subplots given manure in 1998 that had previously either been fertilized or left untreated. Protozoa and bacterivorous and fungivorous nematodes remained more abundant through 1998 and 1999 in previously manure-treated plots than in previously fertilized plots, indicating that the cumulative effects of manure application on enhancement of microbial production can be detected through at least two growing seasons after applications cease. Application of manure for one year to previously non-treated or fertilized soil raised the abundance of protozoa and bacterivorous and fungivorous nematodes to levels comparable to continuously manured soil.

Green Manures and Crop Sequences Influence Potato Diseases and Pathogen Inhibitory Activity of Indigenous Streptomycetes

ABSTRACT A 2-year field trial was conducted to determine the effects of green manures and crop sequences on potato scab and Verticillium wilt. In addition, indigenous streptomycete densities and in vitro pathogen inhibitory activity were measured and their relationships to plant disease were determined. Green manures (buckwheat, canola, or fallow controls) were tested in conjunction with three crop sequences (alfalfa-potato, cornpotato, and potato-potato). Compared with fallow controls, tubers grown in buckwheat-treated soil had significantly lower Verticillium wilt ratings, and tubers grown in buckwheat- or canola-treated soil had greater yields. Potatoes grown in soil planted to corn or alfalfa the previous year had significantly lower Verticillium wilt and potato scab ratings as well as higher yields than potatoes grown in soil previously planted to potato. Streptomycetes from soils collected from green manure-treated plots tended to have greater in vitro pathogen inhibitory activity than streptomycetes from fallow-treated plots. Furthermore, streptomycete pathogen inhibitory activity was frequently negatively correlated with plant disease and positively correlated with potato yield. These results indicate that green manure treatments may contribute to active management of the pathogen inhibitory activity of the streptomycete community to achieve plant disease control.

Rendimiento y componentes de rendimiento de papaya fertilizada con gallinaza en un suelo Coto (Typic Eutrustox)

Se estableció un experimento en un suelo Coto (Typic Eutrustox) para evaluar el uso de gallinaza como fertilizante para papaya. Cuatro niveles de gallinaza (0, 5,10 y 15 t/ha) y cuatro niveles de fertilizante inorgánico 15-15-15 (0,56,112 y 224 g/planta/mes) se evaluaron en todas las posibles combinaciones. Las aplicaciones de gallinaza aumentaron significativamente el peso fresco y seco de las hojas (peciolos y láminas), pero no se observó efecto alguno del fertilizante inorgánico. Las concentraciones de fósforo y potasio aumentaron significativamente en las láminas con la aplicación de 15 t/ha de gallinaza. Las aplicaciones de fertilizante aumentaron el contenido de potasio de las láminas y disminuyeron el contenido de magnesio. La producción de papaya aumentó significativamente con las aplicaciones de gallinaza y fertilizante. La aplicación de 10 y 15 t/ha de gallinaza resultó en una producción de frutas de 42.19 y 54.75 t/ha, respectivamente. Estas producciones fueron significativamente superiores a las obtenidas con las aplicaciones de 0 y 5 t/ha. Los tratamientos de 0, 56,112 y 224 g/planta/mes de fertilizante resultaron en una producción de frutas de 28.11, 42.60, 37.22 y 38.25 t/ha, respectivamente. La producción obtenida con el tratamiento de 0 fertilizante fue significativamente inferior a las de los otros tratamientos, las cuales fueron similares entre sí. Las aplicaciones de gallinaza aumentaron el fósforo disponible (Bray 1-P) de 16.57 a 28.64 mg/kg y el potasio intercambiable de 0.12 a 0.19 cmolc/kg. Las aplicaciones de fertilizante no afectaron estos dos parámetros. Se observó una correlación significativa entre la producción de frutas y el Bray 1-P. El coeficiente de correlación de Pearson fue 0.65 cuando se consideraron todas las parcelas experimentales. Este coeficiente aumentó a 0.82 al considerarse solamente las parcelas tratadas con gallinaza, y disminuyó a 0.25 al considerarse solamente las parcelas tratadas con fertilizante. La gallinaza fue más efectiva que el fertilizante en aumentar el fósforo disponible del suelo. La gallinaza aparentemente previene la fijación de fósforo en el suelo Coto, aumentando su disponibilidad y propiciando una mayor producción de frutas.

Chemical characterization of soil phosphorus and organic matter in different cropping systems in Maine, U.S.A.

To minimize purchased inputs, sustainable agriculture systems often use green- or animal-manure as a nitrogen source for crops. The addition of these materials also have positive impacts on soil phosphorus (P) availability. This study was conducted to investigate the effects of animal- and legume-based cropping systems in place for 5–13 years on the chemistry of organic matter and soil P. Two cropping systems, Potato Ecosystem (ECO) located in Presque Isle, ME, U.S.A. and Grass Fertility (GF) located in Stillwater, ME, U.S.A. received animal manure. Two others, Liebman E Rotation (LER) in Stillwater, ME, U.S.A. and Porter Rotation (PR) in Presque Isle, ME, U.S.A. were primarily legume-based rotations. Estimated difference in carbon input (ha−1 year−1) between the amended and control plots were: ECO, 8100 kg C; GF, 1010 kg; LER, 950 kg C; and PR, 415 kg C. The dissolved organic carbon (DOC) concentration was higher (P < 0.10) in the treatment that received animal manure than those which only received legume residue. The E2/E3 spectrophotometric test indicated that the DOC extracted from the ECO manure-treated plots was more humified than that from the ECO control plots. There were no significant differences between the amended and control treatments in Olsen P or total P for all the tested cropping systems. Similar to that of the DOC response, the ECO cropping system that received animal manure recorded higher concentrations of water soluble P (P < 0.05). There was a linear relationship between DOC and water-soluble P concentrations of the soil:water extract across soils, indicating a positive relationship between them. To determine the effects of the different cropping systems on P bioavailability, a simulation model was used to study how changes in P soil chemistry may affect P uptake by crops. The simulation runs showed that predicted P uptake was greater for the animal manure based ECO and GF systems, but not for the legume based LER and PR systems (P < 0.05). This study shows that cropping systems that include animal manure may increase soil P availability.

Effects of compost, mycorrhiza, manure and fertilizer on some physical properties of a Chromoxerert soil

Addition of organic materials of various origins to soil has been one of the most common rehabilitation practices to improve soil physical properties. Mycorrhiza has been known to play a significant role in forming stable soil aggregates. In this study, a 5-year field experiment was conducted to explore the role of mycorrhizal inoculation and organic fertilizers on the alteration of physical properties of a semi-arid Mediterranean soil (Entic Chromoxerert, Arik clay-loam soil). From 1995 to 1999, wheat ( Triticum aestivum L.), pepper ( Capsicum annuum L.), maize ( Zea mays L.) and wheat were sequentially planted with one of five fertilizers: (1) control, (2) inorganic (160–26–83 kg N–P–K ha −1), (3) compost at 25 t ha −1, (4) farm manure at 25 t ha −1 and (5) mycorrhiza-inoculated compost at 10 t ha −1. Soil physical properties were significantly affected by organic fertilizers. For soil depths of 0–15 and 15–30 cm, mean weight diameter (MWD) was highest under the manure treatment while total porosity and saturated hydraulic conductivity were highest under the compost treatment. For a soil depth of 0–15 cm, the compost and manure-treated plots significantly decreased soil bulk density and increased soil organic matter concentration compared with other treatments. Compost and manure treatments increased available water content (AWC) of soils by 86 and 56%, respectively. The effect of inorganic fertilizer treatment on most soil physical properties was insignificant ( P>0.05) compared with the control. Mycorrhizal inoculation+compost was more effective in improving soil physical properties than the inorganic treatment. Organic fertilizer sources were shown to have major positive effects on soil physical properties.

A preliminary assessment of nitrate degradation in simulated soil environments

This study was directed toward a preliminary assessment of nitrate degradation in northeast Iowa soils. Soil experimental plots were created with variable combinations of fertilizers, ethanol, irrigation, and plant growth. The maximum average concentration of nitrate was much higher in the chemically fertilized plots (500 mg/km) than those fertilized organically (120 mg/kg). This was attributed to the excessive ammonia volatilization from the applied cow manure. Soil nitrate dropped from 155 to 50 mg/kg in a matter of 3 weeks in the deep samples of the intermittently irrigated plots. This is because higher soil moisture lowered the oxygen level, which favored denitrification. Although ethanol seemed to have restricted the release of nitrate in the manure-treated plots, the data are not conclusive. The highest degradation of soil-nitrate (lowest recovered 38 mg/kg) was observed in the plots that simultaneously grew corn, received cow manure, and were not irrigated. Soils in these plots were depleted of nitrogen by ammonia volatilization from manure, and through the uptake by corn plants. Nitrification of organic nitrogen to nitrate was restricted in plots that were left without irrigation. Rain events helped nitrification on the surface, but promoted denitrification at depth.

Use of saline–sodic waters through phytoremediation of calcareous saline–sodic soils

Use of poor-quality groundwater has become inevitable for irrigation to compensate rapidly increasing water demands in many arid and semiarid regions. Salinity and sodicity are the principal soil and water quality concerns in such areas. Many saline–sodic and sodic soils have saline or saline–sodic subsurface drainage waters. Amelioration of these soils needs a source of calcium (Ca 2+) that can replace the excess exchangeable sodium (Na +). Most of these soils, however, contain calcite (CaCO 3) of extremely low solubility. The native calcite does not supply adequate levels of Ca 2+ for soil amelioration as do other chemical amendments. Phytoremediation may help ameliorate such soils through cultivation of certain crops tolerant to ambient soil salinity and sodicity. This amelioration strategy works through plant root action to help dissolve CaCO 3 to supply adequate Ca 2+ without the application of an amendment. During a 3-year field experiment conducted under irrigated conditions, we evaluated phytoremediation against soil application of gypsum and farm manure, and water treatment with sulphuric acid on a calcareous saline–sodic soil (pH s=8.0–8.4, EC e=24–32 dS m −1, SAR=57–78, CaCO 3=45–50 g kg −1 for the top 0.15 m depth; Calcic Haplosalids). A saline–sodic water (EC=2.9–3.4 dS m −1, SAR=12.0–19.4, RSC=4.6–10.0 mmol c l −1, SAR adj=15.6–18.4) was used to irrigate the rice ( Oryza sativa L.) and wheat ( Triticum aestivum L.) crops grown in rotation. Active desalinisation and desodication processes were observed in all the treatments. After the final wheat crop, the 1.2 m soil profile EC e was 7±0.5 dS m −1 and SAR was 15±2 with non-significant treatment differences, indicating comparable soil amelioration effect of phytoremediation with other treatments. Better crop yields were obtained from the manure-treated plots, owing to its annual addition to the soil that possibly improved soil fertility. Phytoremediation needed minimum capital input because no initial investment was made to purchase the amendments.

RUNOFF NUTRIENT AND FECAL COLIFORM CONTENT FROM CATTLE MANURE APPLICATION TO FESCUE PLOTS

ABSTRACT: Grazed pastures represent a potential source of non-point pollution. In comparison to other nonpoint sources (e.g., row-cropped lands), relatively little information exists regarding possible magnitudes of pollution from grazed pasture; how that pollution is affected by weather, soil, management and other variables; and how the pollution can be minimized. The objective of this study was to assess how the quality of runoff from fescue plots is influenced by duration of cattle manure application (4–12 weeks) and manure application strategy (none, weekly application of 1.4 kg/plot, and monthly application at 5.6 kg/plot). Additional analyses were performed to relate runoff quality to the timing of sample collection. The study was conducted at the University of Kentucky Maine Chance Agricultural Experiment Station north of Lexington. Plots (2.4 m wide by 6.1 m long) were constructed and established in Kentucky 31 fescue (Festuca arundinacea Schreb.) to represent pasture. Grazing was simulated by application of beef cattle manure to the plots. Runoff was generated by applying simulated rainfall approximately 4, S and 12 weeks following initiation of manure application. Runoff samples were collected and analyzed according to standard methods for nitrogen (N), phosphorus (P) and fecal coliforms (FC). Runoff concentrations of N and P from manure-treated plots were low and generally not consistently different from control plot concentrations or related to manure application strategy. Runoff FC concentrations from manure-treated plots were higher than from control plot concentrations. Runoff concentrations of ammonia N, total Kjeldahl N, ortho-P and FC decreased approximately exponentially in response to increasing time of sample collection. These findings suggest that manure deposition on well-managed pasture at the rates used in this study might have a negligible impact on nutrient content of runoff.

Introduction of earthworms into an organic arable farming system

Earthworms were inoculated into an experimental field on a reclaimed polder soil in 1988, using a sod transplantation method. The donor field was a clover grass ley in an organic farm with a comparable sandy clay loam soil. The receptor field received different manurial treatments (farmyard manure, deep pit chicken manure or no manure) in replicate plots, and earthworms were introduced into one half of each plot. Five introduced species became established in manured plots, with dispersal rates of about 2 m per year in the first 4 years, increasing to about 11 m per year in the following 4 years and reaching a maximum population density of 776 earthworms per m 2 to a depth of 30 cm. Differences between effects of manurial treatments were not significant, whereas crop and cultivation direction significantly influenced earthworm distribution. The species composition did not differ with manure treatment, but the Shannon–Weaver diversity index was highest in the chicken manure-treated plots and lowest in the unmanured plots

Field studies on two rock phosphate solubilizing actinomycete isolates as biofertilizer sources

Recently biotechnology is focusing attention on utilization of biological resources to solve a number of environmental problems such as soil fertility management. Results of microbial studies on earthworm compost in the University of Nigeria farm identified a number of rock phosphate solubilizing actinomycetes. Two of these, isclates 02 and 13, were found to be efficient rock phosphate (RP) solubilizers and fast-growing cellulolytic microbes producing extracellular hydrolase enzymes. In this preliminary field study the two microbial isolates were investigated with respect to their effects on the growth of soybean and egusi as well as their effect on the incidence of toxicity of poultry droppings. Application of these isolates in poultry manure-treated field plots, as microbial fertilizers, brought about yield increases of 43% and 17% with soybeans and 19% and 33% with egusi, respectively. Soil properties were also improved. With isolates 02 and 13, the soil available phosphorus increased at the five-leaf stage, while N-fixation in the soil increased by 45% or 11% relative to control. It was further observed that air-dried poultry manure after four days of incubation was still toxic to soybean. The toxic effect of the applied poultry manure was reduced or eliminated with microbial fertilizers 02 or 13, respectively.

Abstractions and Runoff from Fescue Plots Receiving Poultry Litter and Swine Manure

This study was conducted to assess the effects of animal manure type (poultry litter vs. swine manure), application rate (218 vs. 435 kg nitrogen/ha), rainfall intensity (50 vs. 100 mm/h), and interactions on initial abstraction, runoff, total abstraction, and curve number for a simulated storm occurring one day after application to plots covered with “tall” fescue. Manure application rate had no significant effects on the hydrologic parameters. The data were then averaged across manure application rates and incorporated with control plot data to determine the effects of manure treatment (control, poultry litter, and swine manure), rainfall intensity, and interaction on the four hydrologic parameters. No differences in mean hydrologic parameter values between the control and litter-treated plots were detected. Initial and total abstractions for the swine manure-treated plots were only approximately 50% of those observed from the control and poultry litter-treated plots. Runoff from the swine manure-treated plots was three times that observed for the control and poultry litter-treated plots at the 50 mm/h rainfall intensity. Curve number for the plots receiving swine manure was 15% greater than that for the control and poultry litter-treated plots. The short-term differences in hydrologic characteristics of the swine manure-treated plots may be attributed to the addition of water via the liquid manure and to soil surface sealing by fine manure particles. Additional work was performed to determine whether the application of the manures affected the hydrologic parameters for longer (4 to 14 days) drying intervals between application and first simulated storm. The results indicated that when the manures were applied at 218 kg nitrogen/ha, hydrologic parameters for the manure-treated plots were no different from those for untreated plots for drying intervals of four days or greater.

Drying Interval Effects on Runoff From Fescue Plots Receiving Swine Manure

Application of swine (Sus scrofa domesticus) manure can lead to elevated runoff concentrations of organic matter and nutrients. This experiment was conducted to assess the influences of swine manure treatment (0 and 220 kg/ha nitrogen applied) and drying interval (4, 7, and 14 days) between manure application and first runoff event on quality of runoff from fescue (Festuca arundinacea Schreb.) plots. Runoff was generated from simulated rainfall (50 mm/h) and sampled at 0.08 h intervals during runoff. Flow-weighted composite runoff samples from each treatment and replication were analyzed for nitrate nitrogen (NO3-N), ammonia nitrogen (NH3-N), total Kjeldahl nitrogen (TKN), total phosphorus (TP), chemical oxygen demand (COD), and total suspended solids (TSS). One set per treatment of the noncomposited runoff samples was also analyzed. Runoff concentrations of all manure constituents investigated were higher for the manure-treated plots than for the untreated plots. Runoff NO3-N increased with drying interval due to nitrification, but concentrations of other manure constituents were unaffected by drying interval. Amounts of constituents lost from the plots in runoff were higher for the manure-treated plots than for the untreated plots, but all (including NO3-N) losses were found independent of drying interval. Analyses of the noncomposited runoff samples revealed high variability in the response of runoff quality to time after the beginning of runoff for all parameters investigated. Data from the non-composited samples did not lend itself to generalized descriptions of changes with respect to time of runoff concentrations of manure constituents.

Use of organic amendments to increase the productivity of sand and gravel spoils: Effect on yield and composition of sweet corn

AbstractCrops grown on sand and gravel spoil areas are subject to temperature, moisture, and nutrient stresses due to the infertile, acidic, and coarse-textured properties of the spoil material. Additions of organic materials such as feedlot manure and sewage sludge compost applied at rates of 40, 80, and 160 Mg/ha were found to improve these spoil areas by providing (1) a more favorable pH for seedling germination and root development, (2) essential crop nutrients, and (3) a greatly increased water content of the spoils in the treated plots compared to fertilized controls. The manure-treated spoil plots had a higher water content than either the compost-treated spoils or the limed and fertilized control plots. In a drought year when the wastes were reapplied, both grain and stalk yields of sweet corn were highest for the manure-treated plots. The low heavy metal content makes these organic materials safe for use as soil conditioners. In addition, uptake and accumulation of toxic metals by sweet corn is generally less than other crops. The interaction between the kind and rate of organic amendment applied, the amount of rainfall in any given growing period, and the water content of the treated spoils determined the final nutrient composition of the stalks, leaves, and grain, as well as the grain and stalk yield.