Liquid Manure Application Research Articles

제주지역에서 건물 함량이 다른 돈분 액비 시용이 이탈리안 라이그라스, 호밀 및 귀리의 수량, 사료가치 및 토양 특성에 미치는 영향

본 연구는 제주도내에서 생산되고 있는 돈분 액비의 건물수준을 달리하여 동계작물에 시용 했을시 사초의 생산성과 사료가치 및 토양특성에 미치는 영향을 구명하려고 수행되었다. 처리는 이탈리안 라이그라스, 호밀 및 귀리에 무비구(TO), 화학비료구(T1) 그리고 2개 건물수준을 가진 돈분 액비구(DM 2.7 %=T2, DM 5.9%=T3)를 분할구배치법으로 하였다. 5.9%의 건물이 함유된 돈분 액비의 시용은 다른 처리에 비하여 세 작물 모두에서 가장 높은 건물 생산성을 보였다(p<0.01). 조단백질 함량(%)과 조단백질 생산량(kg/ha)은 다른 초종에 비하여 호밀에서 가장 높았다(p<0.01), K와 Mg 함량은 다른 초종에서보다 호밀에서 더 높았다(p<0.01). 반면 Na 함량은 다른 초종에서 보다 이탈리안 라이그라스에서 더 높았다(p<0.01). 호밀의 Mg 함량은 다른 초종 보다는 더 높았으며(p<0.01), 특히 2.7% 건물이 함유된 돈분 액비 시용구에서 타 초종보다 높았다(p<0.05). 토양 중 <TEX>$NO_3-N$</TEX> 함량은 다른 작물보다 호밀에서 더 낮았으며(p<0.05), 비료 종류별로는 화학비료구가 더 높았다(p<0.05). 이상의 연구결과를 종합해보면 이탈리안 라이그라스나 귀리보다 겨울철 생육이 좋고 비료 의 이용성이 좋은 호밀이 통계작물로는 좋았다. 그리고 비료는 DM 5.9%의 돈분액비가 DM 2.7%의 돈분액비에 비해 모든 작물의 생산성이 가장 높았다. 또한 <TEX>$NO_3-N$</TEX>의 토양 내 함량도 DM 2.7% 돈분액비나 화학비료 표준구보다 낮았다. 그러나 양돈농가에서는 돈사 청소를 위해 물의 사용을 제한하여 액비중의 건물함량을 높여야 하고, 이러한 방법은 환경오염 문제를 일으키지 않도록 주의를 기울여야 한다.s}20cm$</TEX>에 대해 <TEX>$0.941{\pm}0.008,\;1.032{\pm}0.004,\;1.049{\pm}0.014$</TEX>이다. 치료 계획용 시스템과 수 계산에 의한 MU값의 계산 비교결과 7개 기관의 값이 허용오차 범위를 벗어났다. 쐐기를 제외한 8가지 조건에서 계산된 평균 MU값들은 SAD 조건으로 출력 교정된 장비가 SSD 조건으로 교정된 장비에 비해 6 MV 광자선은 3 MU, 10 MV 광자선은 5 MU 정도 더 높았다. 쐐기를 사용할 경우 MU값은 Varian사 장비와 Siemens사의 장비에 따라 다르고 동일 각의 쐐기를 사용할 경우 Siemens사의 쐐기를 사용할 때 MU값이 크다. 결론: 수집된 광자선 빔 데이터를 분석하여 빔데이터의 정확성과 치료계획용 시스템의 계산 정확성을 대략적으로 점검 할 수 있는 기준 값을 제시하였다.동결이 요구되며 본 연구에서 이용된 OPS 동결 방법이 폭넓게 활용될 것으로 사료된다.며 이 때가 최상의 교배 적기로 사료되며, 혈장 progesterone농도가 4.0 ng/ml 이상으로 증가한 날(Bay 0)을 기준으로 하였을 때부터 CI는 혈장 estradiol-<TEX>$17{\beta}$</TEX> peak 후 1일째인 최고치를 나타내었고, CI peak 후 1일째인 Day 0에 혈장 progesterone 농도가 최초로 4.0 ng/ml 이상으로 증가하여 CI가 90% 이상으로 지속된 시기가 최상의 교배 적기임이 확인되었다. 따라서 혈장 progesterone농도 측정으로 정확한 배란 시기 및 교배 적기를 판정할 수 있으나, 시설비가 저렴하고 검사 방법이 간단한 질 세포 검사가 Shih-tzu 견에서 발정 주기, 교배 적기 및 배란 시기의 판정에 응용될 수 있음을 시사하는 결과라고 사료된다.골계가 높은 This study was conducted to investigate the effects of two dry matter levels of liquid swine manure on dry matter yield and nutritive value of Italian ryegrass, rye and oats, and the chemical characteristics of soil in Jeju. This experiment tested in split plot design. Three forage crops (Italian ryegrass, rye and oats) were the main plot and four fertilizers (no fertilizer=T0, chemical fertilizer=T1, liquid swine manure with DM 2.7%=T2 and liquid swine manure with DM 5.9 %=T3) were the sub plots. Yield and nutrient contents of forage crops and soil properties were determined. Application of liquid swine manure containing 5.9% dry matter resulted in highest DM yield in all three forage crops species compared with the other treatments (p<0.01). Crude protein content(%) and crude protein yield(kg/ha) of forage crops were highest in rye compared with the other forage crops species(p<0.01). K and Mg contents of soil were higher(p<0.01) in rye than in the other species while Na contents was higher(p<0.01) in Italian ryegrass than others. Mg content of soil appeared higher in rye than in the others and higher(p<0.05) in forage crops applied with liquid manure containing 2.7% DM compared with the other species. <TEX>$NO_3-N$</TEX> contents in soil was lower in rye than the other species and higher in species with chemical fertilizer. These findings indicate that most of liquid swine manure produced on local pig farms containing low levels of dry matter and other nutrients suggest a low efficiency of its use as a fertilizer. The liquid swine manure is recommended as a fertilizer for rye production in winter, compared with Italian ryegrass or oat.

2,4-Dichlorophenoxy Acetic Acid Mineralization in Amended Soil

The application of municipal biosolid or liquid hog manure to agricultural soils under laboratory conditions at 20°C influenced the fate of the herbicide 2,4-D [2,4-(dichlorophenoxy)acetic acid] in soil. When 2,4-D was added to soil at agronomic rates immediately after the addition of manure or biosolids to a coarse-textured soil, the percentage of 2,4-D mineralized at 100 days was about 47% for both treatments, compared to only 31% for control soils without amendments. The enhanced 2,4-D mineralization as a result of amendment addition was due to an increased heterotrophic microbial activity, with the greatest increases in soil respiration occurring for soils amended with biosolids. When additions of 2,4-D were delayed for one, two, or four weeks after the amendments were applied, the additions of amendments generally reduced 2,4-D mineralization in soil, particularly for manure, indicating that the effect of amendments on enhancing soil microbial activities diminished over time. In contrast, the mineralization of 2,4-D in control soils was less dependent on when 2,4-D was applied in relation to pre-incubations of soil for zero, one, two, or four weeks. The effect of manure on decreasing 2,4-D mineralization in specific soils was as large as the effect of soil texture on differences in 2,4-D mineralization across soils. Because manure was not found to impact 2,4-D sorption by soil, it is possible that 2,4-D mineralization decreased because 2,4-D transformation products were strongly sorbed onto organic carbon constituents in manure-amended soils and were therefore less accessible to microorganisms. Alternatively, microorganisms were less likely to metabolize the herbicide because they preferentially consumed the type of organic carbon in manure that is a weak sorbent for 2,4-D.

Economic Analysis of an Irrigation System for Liquid Manure Application

Irrigation application of effluent from lagoon based systems is an important aspect of animal manure management in swine rearing facilities. This paper describes a procedure for obtaining least-cost components and operational parameters for an irrigation system used to apply liquid manure. The paper employs propositions from hydraulics—affinity laws and Hazen–Williams formula—to derive statistically estimable relationships between pressure, liquid output, power requirement, and impeller speed of an irrigation system. Coefficient estimates are then used in a spreadsheet based decision support system that employs an optimization program to select the least costly irrigation system. A practical application is showcased through simulation of three hypothetical swine farms. Main findings are that the use of this optimization procedure can result in cost savings for swine growers applying manure by irrigation and that the cost savings potentials increase with the farm size.

Ammonia and nitrous oxide emissions from two acidic soils of Nova Scotia fertilised with liquid hog manure mixed with or without dicyandiamide

Gaseous nitrogen (N) loss from field-applied manure in the form of ammonia (NH 3) and nitrous oxide (N 2O) has negative agronomic, environmental and health implications. This study was undertaken to evaluate the combined effect of soil type and dicyandiamide (DCD) on NH 3 and N 2O emissions following application of liquid hog manure. Soil samples (100 g) were placed in 500 mL screw-top Mason-jars and de-ionised water was added to bring the soil samples to 50%, 70% and 90% water-filled pore space (WFPS). Slurry and slurry + DCD treatments were applied at a rate of 116 000 l ha −1. The jars were then sealed and incubated at 21 °C for 21 d. Ammonia volatilisation was quantified using boric acid traps while N 2O gas concentrations were analysed using gas chromatography. Results showed that DCD had no effect ( p > 0.05) on either NH 3 or N 2O emissions. However, soil type had a significant effect ( p < 0.05) on both gases. Overall, the Pugwash soil produced 3 and 2.5 times more NH 3 and N 2O, respectively, than the Acadia soil. N 2O emissions from both soils increased with an increase in %WFPS, indicating that during the spring and fall in Atlantic Canada, when soils are generally wet, a significant amount of N 2O may be emitted from these soils. The relationship between cumulative N 2O and %WFPS was best described by an exponential function R 2 = 0.83 and p < 0.05 (both soils). Therefore, soil type should be taken into consideration when formulating N 2O emission factors. The addition of DCD together with slurry may not be a viable strategy to mitigate N 2O emissions from acidic soils. To reduce emissions of both gases, livestock slurry should not be applied on wet soils.

Effect of lime, dicyandiamide and soil water content on ammonia and nitrous oxide emissions following application of liquid hog manure to a marshland soil

The loss of nitrogen (N) from field-applied animal manure through ammonia (NH3) volatilisation and nitrous oxide (N2O) emission is of major environmental concern. Both lime and dicyandiamide (DCD) have been suggested as amendments that can mitigate N2O emissions, but simultaneously increase the risk of NH3 volatilisation. This study evaluated the impact of lime and DCD on NH3 and N2O emissions following application of liquid hog manure. Hydrated lime (Ca(OH)2) was added to an acidic soil to achieve three pH levels (4.7, 6.3 and 7.4). Soil samples (100 g) were then placed in 500 ml screw-top Mason-jars and de-ionised water was added to bring the samples to 50, 70 and 90% water-filled pore space (WFPS). Slurry was applied at a rate equivalent to 116,000 l ha−1, while DCD was applied at 30% of the NH4-N rate applied. Jars were sealed and incubated at 21°C for 21 d. Ammonia volatilisation was quantified using boric acid traps, while N2O gas concentration was analysed using gas chromatography. Dicyandiamide had no effect (P>0.05) on either NH3 or N2O emissions. Both NH3 and N2O emissions increased (P<0.05) as WFPS increased, with emissions ranging from 0.9 to 1.4 kg NH3-N ha−1 and 123 to 353 g N2O-N ha−1, respectively. Liming decreased (P<0.01) N2O emissions from 547 to 46 g N2O-N ha−1, but increased (p<0.01) NH3 volatilisation from 0.36 to 1.92 kg NH3-N ha−1. Results suggest that liming to a pH ≥6.3 can reduce N2O emissions, however, this reduction will be accompanied by a substantial loss of NH3.

Aerating Grassland before Manure Application Reduces Runoff Nutrient Loads in a High Rainfall Environment

The effect of mechanically aerating grassland before liquid manure application in the fall on surface runoff and transport of nutrients and solids was studied in a high rainfall area. The two treatments were control and aeration, the latter receiving one pass with an aerator perpendicular to the slope before fall application of liquid manure (dairy in Years 1-3 and swine in Year 4). Treatments were randomly assigned on 3 to 5% sloping land with a silt loam surface soil (Aquic Dystroxerept) planted in orchardgrass (Dactylis glomerata L.). Runoff from natural rainfall events was sampled for nutrient and solids analysis. Aeration significantly reduced runoff and loads of suspended solids, total Kjeldahl N (TKN), and dissolved reactive P in all years. Annual runoff amounts were reduced by 47 to 81%, suspended and volatile solid loads by 48 to 69% and 42 to 83%, respectively, TKN loads by 56 to 81%, and total P (TP) loads by 25 to 75%. Loads of the soluble nutrient NH4-N, dissolved reactive P, and K were reduced by 41 to 83%. The first three runoff events after manure application accounted for approximately one-third of the annual total runoff and solid and nutrient loads when averaged across treatments, with loads of TKN, K, and NH4-N totaling 4.4, 3.3, and 1.9 kg ha-1, respectively. Aeration slightly increased downward movement of NO3-N, but not other nutrients in the soil. Thus mechanical aeration can be an effective tool for reducing runoff and loads of solids and nutrients after surface application of liquid manure on sloping grassland.

Evaluation of the PNM Model for Simulating Drain Flow Nitrate-N Concentration Under Manure-Fertilized Maize

Mathematical models may be used to develop management strategies that optimize the use of nutrients from complex sources such as manure in agriculture. The Precision Nitrogen Management (PNM) model is based on the LEACHN model and a maize N uptake/growth and yield model and focuses on developing more precise N management recommendations. The PNM model was evaluated for simulating drain flow nitrate-nitrogen (NO3-N) in a 3-yr study involving different times of liquid manure application on two soil textural extremes, a clay loam and a loamy sand under maize (Zea mays, L.) production. The model was calibrated for major N transformation rate constants including mineralization, nitrification and denitrification, and its performance was tested using two different calibration scenarios with increasing levels of generalization: (i) separate sets of rate constants for each individual soil type and (ii) a single set of rate constants for both soil types. When calibrated for each manure application treatment for each soil type, the model provided good simulations of monthly and seasonal drain flow NO3-N concentrations. The correlation coefficient (r) and Willmott’s index of agreement (d) ranged from 0.63 to 0.96 and 0.72 to 0.92, respectively. The calibrated model performed reasonably well when rate constant values averaged over manure application treatment for each soil type were used, with r and d values between 0.54 and 0.97, and 0.70 and 0.94, respectively, and greater accuracy for the clay loam soil. When rate constant values were averaged over manure application treatments and soil types, model performance was reasonably accurate for the fall time manure application on the clay loam (r and d of 0.60 and 0.91 and 0.72 and 0.92, respectively) and satisfactory for the spring time on the clay loam and the fall and spring times for the loamy sand soil (r and d between 0.56 and 0.90 and 0.58 and 0.84, respectively). The use of the model for predicting N dynamics under manure-fertilized maize cropping appears promising.

Effect of Manure Application Timing, Crop, and Soil Type on Nitrate Leaching

Timing of manure application affects N leaching. This 3-yr study quantified N losses from liquid manure application on two soils, a Muskellunge clay loam and a Stafford loamy sand, as affected by cropping system and timing of application. Dairy manure was applied at an annual rate of 93 800 L ha(-1) on replicated drained plots under continuous maize (Zea mays L.) in early fall, late fall, early spring, and as a split application in early and late spring. Variable rates of supplemental sidedress N fertilizer were applied as needed. Manure was applied on orchardgrass (Dactylis glomerata L.) in split applications in early fall and late spring, and early and late spring, with supplemental N fertilizer topdressed as NH4NO3 in early spring at 75 kg N ha(-1). Drain water was sampled at least weekly when lines were flowing. Three-year FWM (flow-weighted mean) NO3-N concentrations on loamy sand soil averaged 2.5 times higher (12.7 mg L(-1)) than those on clay loam plots (5.2 mg L(-1)), and those for fall applications on maize-cropped land averaged >10 mg L(-1) on the clay loam and >20 mg L(-1) on the loamy sand. Nitrate-N concentrations among application seasons followed the pattern early fall > late fall > early spring = early + late spring. For grass, average NO3-N concentrations from manure application remained well below 10 mg L(-1). Fall manure applications on maize show high NO3-N leaching risks, especially on sandy soils, and manure applications on grass pose minimal leaching concern.

Effect of repeated manure application on potassium, calcium and magnesium in soil and cereal crops in Saskatchewan

Increasing use of animal manures in Saskatchewan requires information on the effect of manure addition on the availability of soil K, Ca and Mg and their concentrations in plant tissue. To address these issues, we examined the effects of repeated application of liquid swine and solid cattle manure at low and high rates on extractable K, Ca and Mg in soils from three different long-term field trials in Saskatchewan, and on plant K, Ca and Mg concentrations in cereal straw grown on the soils. After 5 to 7 yr of manure application, extractable potassium in the soils was significantly increased, while extractable Ca and Mg tended to remain similar, or was decreased with swine manure addition. In the cereal straw, concentrations of K, Ca, and Mg were all increased by repeated swine manure application, such that there was no significant increase in the K/(Ca + Mg) ratio. However, the K/(Ca + Mg) ratio in the cereal straw grown on soil amended with the high rate of cattle manure was increased. These findings suggest that increased risk of tetany potential from manure application would mainly be associated with excessive application rates of cattle manure in these soils, but should be monitored in feeds grown on all manured soils.Key words:Soil extractable K, Ca, Mg and Na; cereal K, Ca and Mg concentrations, K/(Ca + Mg) ratio, tetany potential, urea, swine manure, cattle manure

Effect of Manure on Glyphosate and Trifluralin Mineralization in Soil

Manure additions to soil may alter soil chemical, physical, and biological characteristics, and thereby change pesticide fate processes in soil. This is the first study to examine the impact of liquid hog manure amendments on glyphosate and trifluralin mineralization in soil. Experiments were conducted in soil microcosms in the laboratory for a total of 332 (glyphosate) and 430 (trifluralin) days. The rate and amount of mineralization of both glyphosate and trifluralin were significantly influenced by the additions of fresh manure to soil in the laboratory and by the history of manure applications in the field. However, the maximum difference in herbicide mineralization between soils that were free of manure application and those amended with manure in the field or in the laboratory was only 6.1% and 7.3% of that initially applied, for trifluralin and glyphosate, respectively. Therefore, we conclude that liquid hog manure application to soil will have no significant effect on the mineralization of glyphosate and trifluralin under field conditions.

Persistence of Escherichia coli and Salmonella in Surface Soil following Application of Liquid Hog Manure for Production of Pickling Cucumbers

Liquid hog manure is routinely applied to farm land as a crop fertilizer. However, this practice raises food safety concerns, especially when manure is used on fruit and vegetable crops. The objectives of this project were to evaluate the persistence of Escherichia coli and Salmonella in surface soil after application of liquid hog manure to fields where pickling cucumbers were grown and to verify the microbiological quality of harvested cucumbers. Mineral fertilizers were replaced by liquid hog manure at various ratios in the production of pickling cucumbers in a 3-year field study. The experimental design was a randomized complete block comprising four replicates in sandy loam (years 1, 2, and 3) and loamy sand (year 3). Soil samples were taken at a depth of 20 cm every 2 weeks after June application of organic and inorganic fertilizers. Vegetable samples were also taken at harvest time. Liquid hog manure, soil, and vegetable (washed and unwashed) samples were analyzed for the presence of Salmonella and E. coli. An exponential decrease of E. coli populations was observed in surface soil after the application of manure. The estimated average time required to reach undetectable concentrations of E. coli in sandy loam varied from 56 to 70 days, whereas the absence of E. coli was estimated at 77 days in loamy sand. The maximal Salmonella persistence in soil was 54 days. E. coli and Salmonella were not detected in any vegetable samples.

Extractable Soil Phosphorus and Inorganic Nitrogen following Application of Raw and Anaerobically Digested Swine Manure

Processing of swine (Sus scrofa domestica) manure in an anaerobic digester for biogas production is not a complete waste treatment process. Therefore, digested manure must be utilized in some manner, most likely as a source of plant nutrients. The objective of this study was to compare the effect of raw and digested liquid swine manure application on soil test P (STP) and inorganic N. A laboratory incubation study was conducted for 112 d, with a factorial combination of raw manure, digested manure, and inorganic fertilizer at five nutrient rates (0, 12.5, 25, 37.5, and 50 mg total P kg−1 and 0, 50, 100, 150, and 200 mg total N kg−1). Raw and digested swine manure produced the same NH4–N disappearance, NO3–N formation, net inorganic N, and increase in STP. Routine STP methods estimated similar P recovery with both manure sources, averaging 21% at the end of incubation. For the first 28 d of incubation, the STP levels were higher for fertilizer than manure; STP levels were similar for all P sources after 28 d. Nitrification of manure NH4 was rapid, reaching background concentrations by 14 d, with conversion rate similar to fertilizer NH4–N. By the end of incubation, maximum net extractable inorganic N, predominantly NO3–N, averaged 20% less than total applied N for both raw and digested manure. Anaerobic digestion did not substantially affect manure nutrient supply, and we conclude that anaerobically digested liquid swine manure can provide similar plant‐available N and P as expected from raw swine manure.

Effects of liquid swine manure applications on NO3–N leaching losses to subsurface drainage water from loamy soils in Iowa

Long-term applications of organic or inorganic sources of N to croplands can increase the leaching potential of nitrate– nitrogen (NO3–N) for soils underlain by subsurface drainage ‘‘tile’’ network. A field study was conducted for 6 years (1993– 1998) to determine the effects of liquid swine manure and urea ammonium nitrate (UAN) solution fertilizer applications on NO3–N concentrations and NO3–N losses with subsurface drainage water under continuous corn (Zea maize L.) and corn after soybean (Glycine max. L.) production systems. The field data collected at Iowa State University’s northeastern research center near Nashua, Iowa, under six N-management treatments and each replicated three times, were analyzed as a randomized complete block design. The flow weighted average (FWA) NO3–N concentrations in tile flow were affected significantly (P < 0.05) by N-application rates from swine manure, growing season and treatment effects. Peak (FWA) NO3–N concentrations values of 31.8 mg L 1 under swine manure and 15.5 mg L 1 under UAN in subsurface drain water were observed in 1995 following the dry year of 1994. The 6-year average crop rotation effects on NO3–N losses with tile flows were not found to be significantly affected either with swine manure or UAN-fertilizer applications but showed significant increase in corn grain yields under both the systems. Liquid swine manure, averaged across the 6-year period, resulted in significantly (P < 0.05) greater NO3–N losses with tile flows by 53% (26 kg N ha 1 versus 17 kg N ha 1 ) and showed no difference in corn grain yields in comparison with UAN-fertilizer applications under continuous corn production system. These results emphasize the need for better management of swine manure application system during the wet and dry growing seasons to reduce NO3–N leaching losses to shallow groundwater systems to avoid contamination of drinking water supplies. # 2005 Published by Elsevier B.V.

Dewatering of phosphorus extracted from liquid swine waste

Phosphorus (P) recovery from liquid swine manure is an attractive technology when on-farm application of liquid swine manure is not an option. We developed a technology that enables separation of this P, but its high moisture content makes transportation difficult. In this work, we investigated dewatering procedures to concentrate the P product. Sludge rich in calcium phosphate (>20% P 2O 5) was obtained using a field prototype, and it was further dewatered using a combination of polymer treatment and filter bags. Anionic polyacrylamide polymer treatment (⩾20 mg/L) was effective to flocculate the P-rich sludge, which enhanced filtration and dewatering. Without polymer, filtration was incomplete due to clogging of filters. Non-woven polypropylene and monofilament filter bag fabrics with mesh size ⩽200 μm retained >99% of suspended solids and total P. Solids content dramatically increased from about 1.5% to >90%. These dewatered solids can be transported more economically off the farm for use as a valuable fertilizer material.

Improving management properties of sandy soils by organo-mineral additives

Sandy soils generally lack of organic and mineral colloids, they have small active surface, low cation exchange capacity (CEC), nutrient supply and buffering capacity and have unfavorable structure developing capability. A common source of organic matter is liquid manure. Application of liquid manure however bears environmental risk, such as leaching of nitrogen or runoff with erosion. (Stefanovits et al., 1999) In the present work, organo-mineral complexes were used to improve the physical and chemical characteristics of sandy soil from the Nyirseg, a representative sandy area of Hungary, to develop better physical, and chemical soil properties and to reduce the hazard of nutrient and organic matter loss and pollution.

SALT THRESHOLDS FOR LIQUID MANURE APPLIED TO CORN AND SOYBEAN

Sprinkler application of liquid manure to growing crops is often a convenient, and agronomically acceptable, means of land application. However, manure salts can cause crop damage, and safe salt concentrations of liquid manure have not been determined. Research was conducted to better understand the relationship of salt concentration to phytotoxicity. Swine (Sus scrofa) manure from a below-barn storage facility was applied during the summer of 2003 to corn (Zea mays L.) and soybean [Glycine max L. (Merr.)] growing on a Kennebec silt loam (fine-silty, mixed, mesic Cumulic Hapludoll) soil under field conditions. The manure had a mean electrical conductivity (EC) of 20.3 dS m-1 and was diluted to EC levels of 11.7, 6.4, and 0.6 dS m-1. The 20.3 dS m-1 and the 6.4 dS m-1 concentrations are typical of under-barn storage and anaerobic lagoons, respectively. The liquid manure was applied to crop canopies at a rate of 11.7 mm ha-1 in three increments over a 10 min period at growth stages V7 or V14 for corn, and V3 or R1 for soybean. At the 20.3 dS m-1 concentration, phytotoxic effects occurred for both crops, although the effects were minor for the corn with application at the V14 stage. At the 11.7 dS m-1 concentration, liquid manure caused leaf necrosis, stunting, and reduced leaf area in soybean, while visible phytotoxic effects were much less severe in corn. Eighty-eight percent of the soybean plants were killed by the 20.3 dS m-1 concentration when applied at the V3 stage. Soybean and corn yields were decreased for the V3 and V7 applications by 89% and 15%, respectively. With the later application of 20.3 dS m-1 concentration, soybean yield was reduced by 45%, but corn yield was not reduced. The V3 application of solutions of 11.7 and 6.4 dS m-1 caused an 8.5% decrease in soybean yields. Application of 11.7 dS m-1 liquid manure at V7 reduced corn yield by 12% but increased yield by 10% when applied at V14. Application of 6.4 dS m-1 liquid manure increased corn yield by 4% and 13% for the V7 and V14 applications, respectively, compared to the control. Under the conditions of this study, application of liquid manure of 6.4 dS m-1 or less should be safe for all stages of soybean and corn, while 11.7 dS m-1 should be safe for soybean after R1 and for corn after V7. Further research is needed to evaluate these results across several growing environments and to determine potential differences in plant damage threshold.

COVER CROP/DAIRY MANURE MANAGEMENT SYSTEMS: WATER QUALITY AND SOIL SYSTEM IMPACTS

A field study was conducted to determine impacts of corn silage production systems that included a rye cover cropand application of liquid dairy manure in the spring and fall on water quality and soil characteristics. Four managementsystems were each replicated four times: traditional, double-crop, roll-down, and undercut. Manure was applied below thesoil surface during the undercutting process; otherwise, manure was surface applied. In the roll-down system, the rye cropwas flattened with a heavy roller after manure application. Rainfall was simulated within 48 h of manure application toproduce runoff events. Grab samples of runoff were collected and composited for analysis. Soil samples were collected priorto treatments in the fall and spring. The roll-down system had no significant effect on water quality (sediment, nutrients,bacteria) as compared to the traditional system. While the roll-down system may require an occasional tillage operation toprevent surface compaction, it is recommended in situations where reduction of residual herbicide applications is a primaryconcern. The undercut system displayed evidence of a compaction layer developing below the disturbed soil layer. Theundercut system reduced loadings of all nutrients, but increased losses of total suspended solids, as compared with all othersystems. Mean volume of runoff from the undercut system was less than half that from any other system. Overall, the undercutsystem is recommended over the other systems analyzed for preventing transport of manure constituents to surface water, butshould be evaluated in a complete dairy system before it is implemented by producers.

Características químicas de solo submetido ao tratamento com esterco líquido de suínos e cultivado com gramíneas forrageiras

Avaliou-se, neste trabalho, o efeito da aplicação intensiva de esterco líquido de suínos (ELS), pelo método do escoamento superficial, nas características químicas de um solo Podzólico Vermelho-Amarelo cultivado com quatro espécies forrageiras: quicuio da Amazônia (Brachiaria humidicola (Rendle) Schweick), braquiária (Brachiaria decumbens Stapf), coastcross (Cynodon dactylon (L.) Pers.) e tifton 85 (Cynodon spp.). O ELS foi aplicado em parcelas de 4m² e com 5% de declividade, durante 4 meses, na taxa média equivalente a 800kg ha-1d-1 de demanda bioquímica de oxigênio (DBO5). Para caracterização química, amostras de solo foram coletadas à profundidade de 0-0,20m, antes de iniciar o experimento e após o término dele. A aplicação de ELS proporcionou acúmulo de P, K, Na e Zn no solo, enquanto as concentrações de Mg e Cu diminuíram e a de Ca se manteve inalterada. Houve aumento na acidez, na soma de bases, na CTC e redução na saturação por bases. Devido ao acúmulo de nutrientes, recomenda-se monitoramento das características químicas do solo, ao longo de seu perfil e das águas subterrâneas para que se avaliem riscos de contaminação ambiental.

Phosphorus amounts and distribution in a Saskatchewan soil after five years of swine and cattle manure application

Repeated application of animal manures to Saskatchewan soils has led to interest in the fate and distribution of residual manure P in the soil. The concentrations of soil phosphorus in various inorganic and organic fractions were investigated in soils sampled from long-term field research plots (Dixon, SK) with a 5-yr history of annual application of liquid swine manure or solid cattle manure at low, medium and high rates. The soil type at the research site is a loamy textured Black Chernozem (Cudworth Association). Annual rates of manure application over the 5 yr were based on the N contents in the manures and were equivalent to 0 (control), and approximately 100 (low), 200 (medium) and 400 (high) kg total N ha-1 yr-1 as manure. For comparison, urea alone was also applied at rates of 50, 100 and 200 kg N ha-1 yr-1. The total P concentration in the surface soil (0&amp;ndash15 cm) was significantly increased only by the addition of cattle manure and only in the medium and high rate treatments compared to the control. The most labile P fractions (Resin-P and NaHCO3-P) were also significantly increased with increasing rate of cattle manure addition. No significant increases in either soil total P or labile P fractions were observed in liquid swine manure treatments, which is attributed to the lower amount of P added with the swine manure treatment than the cattle manure treatment. Added P in the swine manure treatment more closely matched P removal in crop harvest compared to cattle manure treatment, which had more P added than was removed by the crop. Key words: Phosphorus fractions, labile P fraction, sequential P extraction, urea, swine manure, cattle manure

Herbage yield and crude protein concentration of rangeland and pasture following hog manure application in southeastern Alberta

Intensive hog production is expanding into semi-arid regions of Alberta, where perennial forage lands are increasingly targeted for manure applicati on despite limited guidelines for its efficient use. Herbage yield and crude protein were assessed over two consecutive years within two native rangelands and two tame pastures, following different rates (10, 20, 40, 80 and 160 kg ha-1 NH4-N), methods (surface banding vs. subsurface injection) and seasons (fall vs. spring) of one-time liquid hog manure (LHM) application. Increasing manure rates improved grass yield across all sites the first growing season after treatment, from 1626 to 3576 kg ha-1. Although absolute increases in production were greatest on tame pasture, relative yield increases were similar among sites. Average crude protein (CP) concentration also increased from 69 to 91 g kg-1 in the first year. Despite low rainfall and the absence of a yield response in the second year, grass CP and crude protein yield (CPY) were maximized with increased manure application, highlighting the positive effects of manure on forage production, even with drought. Forb yields demonstrated variable effects among sites, with increasing manure decreasing alfalfa and increasing native forbs. Overall, both semi-arid tame pastures and native rangelands responded positively to LHM application, highlighting the complementary nature of hog and forage production under these conditions. Key words: Crude protein yield, forage, hog manure, injection, native rangeland, precipitation