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Agricultural Greenhouse Gas Inventory Research Platform - InveN2Ory. Dung and urine experimental site in County Down, 2012

Related Party - Individual (Point of Contact): Doctor Rachael Carolan (AFBI)
Related Party - Organisation (Author): AFBI
Related Party - Organisation (Funder): Defra
Related Party - Organisation (Funder): Scottish Government
Related Party - Organisation (Funder): Welsh Assembly Government
Related Party - Organisation (Funder): DAERA Northern Ireland
An experiment was carried out at the AFBI Hillsborough research farm near Hillsborough, south-east Northern Ireland (sandy clay loam/clay loam topsoil texture) using small field plots (3 x 8 m) arranged in a randomised block design with three replicates per treatment. Cattle urine (at 5 L/m2), synthetic urine (at 5 L/m2) and cattle dung (at 20 kg/m2) was applied to grassland in early-April (spring), late-June (summer) and in mid-September (autumn) 2012. The synthetic urine was prepared using the formulation described for “R2” in the paper by Kool et al., (2006). A control treatment was included where no urine or dung was applied. In a separate treatment, a commercially available nitrification inhibitor was tested; dicyandiamide (DCD) was pre-mixed with the urine prior to application to give an application rate of 10 kg /ha for the DCD. The urine and dung was collected from lactating dairy cows at the AFBI Hillsborough research farm, kept refrigerated at <4°C and applied within seven days of collection. Following urine application to five 0.36 m2 areas of the plot (‘urine patches’), measurements of direct N2O-N were made over c.12 months, using 5 40 x 40 cm stainless steel static chambers (1 per 0.36 m2 area, giving a total chamber surface area of 0.8 m2) and analysed by gas chromatography. Dung was applied using a trowel in five patches (40 cm x 40 cm) so that each patch was completely enclosed by a nitrous oxide static chamber. For soil mineral N and grass N uptake measurements, two additional areas of 2 m x 2 m were treated on each plot; one with 20 litres of urine and one with 80 kg of dung. Grass yields and N offtakes were measured following grass cuts in late-May, mid-July and early-September 2012 from the spring dung and urine application, early-September 2012 and late-May 2013 from the summer dung and urine application, and late-May, late-July and mid-September 2013 from the Autumn dung and urine application. The County Down, 2012 dung and urine experiment contains data sets of; annual nitrous oxide emissions, annual nitrous oxide emission factors, soil moisture, top soil mineral nitrogen (selected dates), temperature, rainfall and associated crop (grass yield and nitrogen offtakes) and soil measurements. Reference: Kool, D.M., Hoffland, E., Abrahamse, P.A and van Groenigen, J.W. (2006). What artificial urine composition is adequate for simulating soil N2O fluxes and mineral N dynamics? Soil Biology and Biochemistry 38, 1757-1763.

Subject Keywords: Nitrous oxideUrineSynthetic urineDungNitrification inhibitorsDCDApplication timingGrassland soils
Geographic Keywords: County DownSouth East Northern IrelandNorthern IrelandUnited Kingdom
Phenomenon Time -  Start Date/Time: 2012-04-03 00:00:00 End Date/Time:  2013-09-09 00:00:00

Geographic Extent -
    Longitude (West): -6.22
    Longitude (East): -5.95
    Latitude (South): 54.37
    Latitude (North): 54.53

Data Quality Statement:
The Agri-Food and Biosciences Institute (AFBI) is involved in the conduct of scientific Research and Development and the provision of specialist scientific analytical and diagnostic services. AFBI is committed to the delivery of high quality scientific services to its customers. Achievement of high quality and consistency calls for a systematic and disciplined approach by all staff in all activities associated with the delivery of the customer's specific requirements. In order to manage quality performance, the Institute has implemented a Quality Management System (QMS), which meets the requirements of the internationally accepted standard for Quality Management Systems, ISO 9001:2008. The AFBI QMS provides a structured process for the achievement of continual quality improvement in that it seeks for customer and regulatory requirements to be consistently met and customer satisfaction enhanced. The Institute prepares and effectively implements documented procedures, protocols and instructions in accordance with the requirements of the QMS. QMS documentation is structured into three main levels: the Quality Policy Manual, which includes overall policy statements and responsibilities, and acts as a signpost to related system documentation; the Quality Procedures Manual, which includes quality procedures for each Branch within the Institute detailing how personnel in these areas implement the QMS; and Standard Operating Procedures (SOPs), which are supporting protocols and methodological documentation relevant to the operation of the QMS. All personnel whose work may create a significant effect on quality have received appropriate training in performance of their assigned tasks. The training programme reflects changing methods and techniques and includes briefing on the QMS. Training records are recorded and kept up-to-date for all personnel. The Institute is committed to the ongoing improvement of its Quality Management System through the establishment and ongoing review of specific measurable quality objectives, and the involvement of staff in meeting these objectives. All aspects of the QMS are subject to annual review, with an emphasis on continuous improvement, by the senior management team to ensure its continuing suitability, adequacy and effectiveness. All documents within the QMS are reviewed periodically by senior management, internally audited and revised when and where necessary according to established and documented change control procedures within the QMS system. All QMS documentation is available to staff on the AFBI Intranet, and staff are trained to understand the quality issues relevant to their own activities and how they can contribute to the attainment of the Institute’s quality improvement objectives by strict adherence to work relevant QMS documentation (e.g. SOPs). AFBI’s entire Research & Development (R&D) programme, major SLAs with public sector organisations, most on-demand services, and statistical analysis are either certified to the ISO 9001:2008 standard or accredited under ISO 17025:2005, in the case of some services. All accredited activities within AFBI are regularly monitored by an independent UKAS accredited third party certification body, and key services are assessed by participation in external proficiency testing schemes to ensure that the highest quality standards are maintained. Detailed nitrous oxide emission measurement methodology: Direct N2O emissions were measured with five static flux chambers (40 cm wide x 40 cm long x 25 cm high) per plot, covering a total surface area of 0.8 m2. The chambers were stainless steel and un-vented. Adhesive-backed expanded neoprene, 6 mm thick, was inserted into the 3 cm diameter channel on the upper rim of each chamber base, and a 10 kg drum filled with water placed on top of the chamber lid, to ensure an air-tight seal formed following chamber closure (Smith et al., 2012). Chambers were pushed into the soil up to a depth of 5 cm and remained in place throughout the experiment, except during urine/dung application and grass cutting when chambers were removed, locations were marked, and chambers were re-instated to the same position as prior to removal. Chambers remained open except for a short time on each sampling day. On that day, ten samples of ambient air were taken to represent time zero (T0) N2O samples. From each chamber, after a 40-minute enclosure period (T40) a headspace sample was taken using a 20-ml syringe and injected into a pre-evacuated, pre-labelled 12 ml Labco vial fitted with a double-wadded PTFE/silicone septum, which were over pressurised during storage. Immediately before Gas Chromatography (GC) analysis, vials were vented to atmospheric pressure by piercing the septa with a 25 gauge needle. The N2O flux was calculated using an assumed linear increase in N2O concentration from the ambient N2O concentration (T0) to the N2O concentration inside the chamber after 40-minutes enclosure (T40) (Chadwick et al., 2014). Throughout each experiment, the linearity of emissions through time was checked routinely from three chambers located on the urine only treatment. A minimum of seven samples were taken from each chamber at 10 min intervals commencing at closure i.e. T0, T10, T20, T30, T40, T50, T60. A duplicate sample was taken along with the linearity sample at T40. In order to minimise the effect of diurnal variation, gas sampling was carried out between 10:00 am and 12:00 pm as referred to in the IPCC good practice guidance (IPCC, 2000). Gas samples were analysed as soon as possible after collection to minimise potential leakage (usually within 2 weeks of field measurements) using gas chromatographs fitted with an electron-capture detector and an automated sample injection system. Following receipt in the laboratory, six freshly prepared standards per sampling day (two replicates of each standard) were stored with the samples and were used to verify sample integrity during storage. The gas chromatographs were calibrated on a daily basis using certified N2O standard gas mixtures. An exchange of samples of chamber air and standard gas mixtures between labs from the different research organisations involved in the InveN2Ory programme of experiments who operated the GCs were carried out, to avoid the possibility of any bias in the results towards high or low values. Following urine/dung application, N2O flux measurements were carried out in line with the following sampling schedule until either the next fertiliser application or the final application at the end of the monitoring period; measurements were taken on four occasions in the week of, and week after, fertiliser application, twice weekly for the next two weeks, every other week over the next c.four months, decreasing in frequency to monthly until the end of the 12 month sampling period. Prior to the urine/dung application N2O measurements were taken to provide baseline information. This sampling schedule resulted in an annual total of c.30 sampling days starting from the day of each of the urine/dung application. Measurements were taken over 12 months to follow IPCC good practice guidance and so that the results were directly comparable to the IPCC 2006 methodology default emission factor. Nitrous oxide fluxes from the five replicate chambers per plot were averaged. Cumulative fluxes were calculated using the trapezoidal rule to interpolate fluxes between sampling points. References: Chadwick, D.R., Cardenas, L., Misselbrook, T.H., Smith, K.A., Rees, R.M., Watson, C.J., McGeough, K.L., Williams, J.R., Cloy, J.M., Thorman, R.E. & Dhanoa, M.S. (2014). Optimizing chamber methods for measuring nitrous oxide emissions from plot-based agricultural experiments. European Journal of Soil Science 65, 295-307. (IPCC, 2000). Good Practice Guidance & Uncertainty Management in National Greenhouse Gas Inventories. Penman, J., Kruger, D., Galbally, I., Hiraishi, T., Nyenzi, B., Emmanul, S., Buendia, L., Hoppaus, R., Martinsen, T., Meijer, J., Miwa, K. znd Tanabe, K. (Eds). IGES, Japan. Smith K.A., Dobbie K.E., Thorman R., Watson C.J., Chadwick D.R., Yamulki S. & Ball B.C. (2012). The effect of N fertilizer forms on nitrous oxide emissions from UK arable land and grassland. Nutrient Cycling in Agroecosystems 93, 127-149.
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Rights Statement

This data is published under the licence FBA Licence

Attribution: McGeough, K.L., McNeill, G., Laughlin R.J. and Watson, C.J.

Citation of this data should be as follows:
McGeough, K.L., McNeill, G., Laughlin R.J. and Watson, C.J. (2017): Agricultural Greenhouse Gas Inventory Research Platform - InveN2Ory. Dung and urine experimental site in County Down, 2012. Version:1. [dataset] Freshwater Biological Association [publisher]. doi:10.17865/ghgno570

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