• Modelling Phosphorus for Grassland: Agronomically and Environmentally Sustainable Advice

      Schulte, Rogier P. (Teagasc, 01/01/2006)
      In 2006, the Nitrates Directive (through S.I. 378 (Anon, 2006)) was implemented in Ireland, aimed at reducing nutrient losses from agriculture to water bodies, i.e. surface waters, groundwater and estuarine waters. This legislation introduced strict regulation of nutrient management on Irish farms. Thus far, nutrient management had largely been based on Teagasc advice (Coulter, 2004). However, in the new policy climate, in addition to advice, compliance with legal limits is also required. This significant change in the practicalities surrounding nutrient management led to a review of Teagasc nutrient (phosphorus and nitrogen) advice, based on the following considerations: Traditionally, nutrient advice had largely been based on fertiliser rates for economically optimal productivity, i.e. rates at which further fertiliser applications would not result in higher economic returns. Now, SI 378 of 2006 demands that nutrient application rates do not exceed crop (grass) demand, nor result in nutrient losses that may have a negative impact on water quality. Previous phosphorus (P) advice (Coulter, 2004) was similar for all soil types, and did not account for potentially different P-requirements, or indeed potentially different risks of P-loss to water between soils. Previous P advice was based on returning optimum crop yields. However, grassland management in Ireland is increasingly focussed on maximising the amount of herbage grazed in situ. With extended grazing seasons and an increasing share of the animal diet consisting of grazed herbage, the scope and flexibility of diet supplementation through straights and concentrates is reduced. An increasing proportion of dietary P must be obtained from this grazed herbage as a result. Therefore P fertiliser strategies should no longer be based on yield responses alone, but in addition sustain adequate herbage P-concentrations in order to ensure that the dietary P requirements can be met on a non-supplemented diet of grazed herbage. Against this background, Teagasc, Johnstown Castle Environment Research Centre, undertook a major research programme, reviewing both agronomic and environmental aspects of P-advice for grassland.
    • Mapping the broad habitats of the Burren using satellite imagery

      Parr, Sharon; O’Donovan, Grace; Finn, John (Teagasc, 01/03/2006)
      This project has successfully used satellite imagery to survey and map the extent and spatial distribution of broad habitat types within the Burren, and we have represented this information on a digitised habitat map. this information on a digitised habitat map. This map is the first to show the distribution of the broad habitats of the Burren and will be an important tool in aiding future decisions as to how the habitats of the Burren should be managed to the benefit of both the farmer and the environment. The map provides the first estimate of the area of the Burren affected by scrub encroachment – this being one of the most significant threats to the EU priority habitats in the region. On a particularly challenging area with a high diversity and complexity of habitats, remote sensing appears to offer a very effective and cost-efficient alternative to broad-scale habitat mapping on a field-by-field basis. The use of high-resolution imagery and ground-truthing should be adopted to complete a detailed national survey of habitats and land use in Ireland. This would support more effective implementation of both the Agriculture sector’s obligations under the Habitats Directive, and agri-environmental schemes with wildlife objectives. The outputs provided by such mapping approaches could inform the targeting of agri-environmental objectives, and increase the efficiency of detecting areas of high conservation value for monitoring by more conventional methods. The detailed land use descriptions offered by such imagery are also of high relevance to modelling approaches and risk assessment for implementation of land use policies such as the Water Framework Directive and Nitrates Directive.
    • Nitrous Oxide Emissions

      Hyde, Bernard; Ryan, Mary; Hawkins, M.; Connolly, J.; Carton, Owen T.; Environmental Protection Agency (Teagasc, 01/04/2005)
      Nitrous oxide (N2O) is one of the three most important greenhouse gases (GHG). Nitrous oxide emissions currently account for approximately one third of GHG emissions from agriculture in Ireland. Emissions of N2O arise naturally from soil sources and from the application of nitrogen (N) in the form of N fertilizers and N in dung and urine deposition by grazing animals at pasture. Nitrous oxide emission measurements were conducted at three different scales. Firstly, a large-scale field experiment was undertaken to compare emission rates from a pasture receiving three different rates of N fertilizer application and to identify the effects of controlling variables over a two-year period. Variation in emission rates was large both within and between years. Two contrasting climatic years were identified. The cooler and wetter conditions in year 1 gave rise to considerably lower emission levels than the warmer and drier year 2. However, in both years, peak emissions were associated with fertilizer N applications coincident with rainfall events in the summer months. A small-plot study was conducted to identify the individual and combined effects of fertilizer, dung and urine applications to grassland. Treatment effects were however, difficult to obtain due to the overriding effects of environmental variables. Thirdly, through the use of a small-scale mini-lysimeter study, the diurnal nature of N2O emission rates was identified for two distinct periods during the year. The occurrence of a diurnal pattern has important implications for the identification of a measurement period during the day which is representative of the true daily flux. The research presented aims to identify the nature and magnitude of N2O emissions and the factors which affect emission rates from a grassland in Ireland. Further work is required to integrate the effects of different soil types and contrasting climatic regimes across soil types on N2O emissions.
    • Pathways for nutrient loss to water with emphasis on phosphorus

      Tunney, Hubert; Kiely, G.; Morgan, G.; Moles, R.; Byrne, P.; Jordan, P.; Daly, Karen M.; Doody, Donnacha G.; Kurz, Isabelle; Bourke, David; O’Reilly, C.; Ryan, T. Declan; Holden, N.; Jennings, E.; Irvine, K.; Carton, Owen T. (Teagasc, 01/06/2007)
      The main objective of this project was to study phosphorus (P) loss from agricultural land under a range of conditions in Ireland, to quantify the main factors influencing losses and make recommendations on ways to reduce these losses. This report is a synthesis of the main conclusions and recommendations from the results of the studies. The final reports from the individual sub-projects in this project are available from the EPA (www.epa.ie).
    • The impact of the grazing animal on phosphorus, nitrogen, potassium and suspended solids loss from grazed pastures, Part A

      Tunney, Hubert; Kurz, Isabelle; Bourke, David; O’Reilly, Colin; Jeffrey, D.; Dowding, P.; Foy, B.; Kilpatrick, D.; Haygarth, P. (Teagasc, 01/06/2007)
      In Ireland 90% of the 4.2 million ha of farmland is grassland. Phosphorus deficiency limited grassland production in Ireland and this was corrected by chemical fertiliser use in the 1960s and 1970s. The increased inputs of fertilisers led to increased intensification of grassland with a doubling of grass yield and of grazing animal numbers, from about 3 million to over 6 million livestock units. There is little information on relative contribution of increased chemical fertiliser use compared to increased grazing animal numbers on phosphorus loss to water. The main objective of this study was to obtain information on nutrient loss, particularly phosphorus, in overland flow from cut and grazed grassland plots, with a range of soil test phosphorus levels over three years and implications.
    • The impact of grazing cattle on soil physical properties and nutrient concentrations in overland flow from pasture, Part B

      Kurz, Isabelle; O’Reilly, Conor; Tunney, Hubert; Bourke, David; Environmental Protection Agency (Teagasc, 01/06/2007)
      The loss of nutrients from agricultural land to water bodies is a serious concern in many countries. To gain information on the contribution of grazing animals to diffuse nutrient losses from pasture areas to water, this study looked at the impact of cattle on nutrient concentrations in overland flow and on soil hydrology (bulk density, macroporosity and resistance to penetration). Rainfall simulations to produce overland flow were conducted and soil physical measurements were taken on experimental plots assigned to one of two treatments: 1) cattle had unrestricted access to the plot; 2) cattle could graze the plot but they could neither walk on the plot area nor deposit excrements on it. Areas to which the cattle had free access were characterised by 57%-83% lower macroporosity, by 8%-17% higher bulk density and by 27%-50% higher resistance to penetration than areas from which the cattle were excluded. The nutrients in overland flow from grassland that were affected by the presence of grazing animals were mainly the particulate nitrogen, the organic phosphorus and the potassium concentrations. Overall, the presence of cattle had a longer lasting effect on the soil hydrological parameters measured than on the nutrient concentrations in overland flow.
    • National Soils Database

      Fay, Deirdre; McGrath, David; Zhang, Chaosheng; Carrigg, Cora; O’Flaherty, Vincent; Kramers, Gaelene; Carton, Owen T.; Grennan, Eamonn (Teagasc, 01/07/2007)
      The objectives of the National Soils Database project were fourfold. The first was to generate a national database of soil geochemistry to complete the work that commenced with a survey of the South East of Ireland carried out in 1995 and 1996 by Teagasc (McGrath and McCormack, 1999). Secondly, to produce point and interpolated spatial distribution maps of major, minor and trace elements and to interpret these with respect to underlying parent material, glacial geology, land use and possible anthropogenic effects. A third objective was to investigate the microbial community structure in a range of soil types to determine the relationship between soil microbiology and chemistry. The final objective was to establish a National Soils Archive.
    • An inter-laboratory comparison of multi-enzyme and multiple substrate-induced respiration assays to assess method consistency in soil monitoring

      Creamer, Rachel E.; Bellamy, Pat; Black, Helaina I. J.; Cameron, Clare M.; Campbell, Colin D.; Chamberlain, Paul; Harris, Jim; Parekh, Nisha; Pawlett, Mark; Poskitt, Jan; Stone, Dote; Ritz, Karl; UK Department of Environment, Food and Rural Affairs (Defra) (Springer-Verlag, 01/07/2009)
      The use of indicators in soil monitoring schemes to detect changes in soil quality is receiving increased attention, particularly the application of soil biological methods. However, to date, the ability to compare information from different laboratories applying soil microbiological techniques in broad-scale monitoring has rarely been taken into account. This study aimed to assess the consistency and repeatability of two techniques that are being evaluated for use as microbiological indicators of soil quality; multi-enzyme activity assay and multiple substrate induced respiration (MSIR). Data was tested for intrinsic (within-plate) variation, inter-laboratory repeatability (geometric mean regression and correlation coefficient) and land-use discrimination (principal components analysis, PCA). Intrinsic variation was large for both assays suggesting that high replicate numbers will be required. Inter-laboratory repeatability showed diverging patterns for the enzyme assay and MSIR. Discrimination of soils was significant for both techniques with relatively consistent patterns, however combined laboratory discrimination analyses for each technique showed inconsistent correspondence between the laboratories. These issues could be addressed through the adoption of reliable analytical standards for biological methods along with adequate replication. However, until the former is addressed, dispersed analyses are not currently advisable for monitoring schemes.
    • The Farmland Wildlife Survey – raising awareness of wildlife habitats

      Gabbett, Mairead; Finn, John; The Heritage Council (Teagasc, 01/08/2005)
      The Farmland Wildlife Survey involved a short visit (about 3 hours) to 19 REPS demonstration farms, and an identification of habitats and wildlife on each farm, with an emphasis on common farmland habitats such as hedgerows, ponds, watercourses, field margins, woodland, plant species and other areas of wildlife value. The survey results were provided to the farmer and Teagasc REPS advisor as a report with colour pictures of representative habitats, and an explanation of why these habitats were important for wildlife.
    • Digital Soil Information System for Ireland – Scoping Study

      Daly, Karen M.; Fealy, Reamonn; Environmental Protection Agency (Environmental Protection Agency, 01/09/2007)
      Soil is our life support system, crucial for the production of food and biomass and critical for the sustainability of an agro–environmental economy. The authors suggest that it is axiomatic that Ireland should have ready access to its soil information through the benefits of modern information technology. Soil is a multifunctional and complex natural medium that provides ecosystem services such as the production of food, fibre and fuel, the provision of habitat, nutrient cycling, contaminant transformation, water cycling and climate regulation. Reports from the European Commission indicate that many of these functions and services are under threat and soil protection is now placed on the same level as that of water and air.
    • Chemical amendment of pig slurry: control of runoff related risks due to episodic rainfall events up to 48 h after application

      O'Flynn, Cornelius J.; Healy, Mark G.; Wilson, Paul; Hoekstra, Nyncke J.; Troy, Shane M.; Fenton, Owen; Irish Research Council for Science, Engineering and Technology (Springer, 01/09/2013)
      Losses of phosphorus (P) from soil and slurry during episodic rainfall events can contribute to eutrophication of surface water. However, chemical amendments have the potential to decrease P and suspended solids (SS) losses from land application of slurry. Current legislation attempts to avoid losses to a water body by prohibiting slurry spreading when heavy rainfall is forecast within 48 h. Therefore, in some climatic regions, slurry spreading opportunities may be limited. The current study examined the impact of three time intervals (TIs; 12, 24 and 48 h) between pig slurry application and simulated rainfall with an intensity of 11.0±0.59 mm h-1. Intact grassed soil samples, 1 m long, 0.225 m wide and 0.05 m deep, were placed in runoff boxes and pig slurry or amended pig slurry was applied to the soil surface. The amendments examined were: (1) commercial-grade liquid alum (8% Al2O3) applied at a rate of 0.88:1 [Al/total phosphorus (TP)] (2) commercial-grade liquid ferric chloride (38% FeCl3) applied at a rate of 0.89:1 [Fe/TP] and (3) commercial-grade liquid poly-aluminium chloride (10 % Al2O3) applied at a rate of 0.72:1 [Al/TP]. Results showed that an increased TI between slurry application and rainfall led to decreased P and SS losses in runoff, confirming that the prohibition of land-spreading slurry if heavy rain is forecast in the next 48 h is justified. Averaged over the three TIs, the addition of amendment reduced all types of P losses to concentrations significantly different (p<0.05) to those from unamended slurry, with no significant difference between treatments. Losses from amended slurry with a TI of 12 h were less than from unamended slurry with a TI of 48 h, indicating that chemical amendment of slurry may be more effective at ameliorating P loss in runoff than current TI-based legislation. Due to the high cost of amendments, their incorporation into existing management practices can only be justified on a targeted basis where inherent soil characteristics deem their usage suitable to receive amended slurry.
    • Methodology for environmental assessment of agri-environment schemes: the Agri Environmental Footprint Index

      Finn, John A.; Louwagie, G.; Northey, G.; Purvis, G.; Balazs, K.; Mortimer, S.R.; Primdahl, J.; Vesterager, J.-P.; AE-Footprint project (Teagasc, 01/11/2010)
      Agri-environment schemes pay farmers for the provision of environmental services. Such schemes tend to have multiple measures that deliver multiple environmental objectives, and there is a lack of consistent methodology with which to measure the environmental benefits of such schemes. Funded by EU FP6, the Agri-Environment Footprint project (www.footprint.rdg.ac.uk) aimed to address this challenge, and this report provides results from selected components of the project.
    • Impact of chemical amendment of dairy cattle slurry on phosphorus, suspended sediment and metal loss to runoff from a grassland soil

      Brennan, R. B.; Fenton, Owen; Grant, Jim; Healy, Mark G.; Teagasc Walsh Fellowship Programme (Elsevier, 01/11/2011)
      Emerging remediation technologies such as chemical amendment of dairy cattle slurry have the potential to reduce phosphorus (P) solubility and consequently reduce P losses arising from land application of dairy cattle slurry. The aim of this study was to determine the effectiveness of chemical amendment of slurry to reduce incidental losses of P and suspended sediment (SS) from grassland following application of dairy cattle slurry and to examine the effect of amendments on metal concentrations in runoff water. Intact grassed-soil samples were placed in two laboratory runoff boxes, each 200-cm-long by 22.5-cm-wide by 5-cm-deep, before being amended with dairy cattle slurry (the study control) and slurry amended with either: (i) alum, comprising 8% aluminium oxide (Al2O3) (1.11:1 aluminium (Al):total phosphorus (TP) of slurry) (ii) poly-aluminium chloride hydroxide (PAC) comprising 10% Al2O3 (0.93:1 Al:TP) (iii) analytical grade ferric chloride (FeCl2) (2:1 Fe:TP), (iv) and lime (Ca(OH)2) (10:1 Ca:TP). When compared with the study control, PAC was the most effective amendment, reducing dissolved reactive phosphorus (DRP) by up to 86% while alum was most effective in reducing SS (88%), TP (94%), particulate phosphorus (PP) (95%), total dissolved phosphorus (TDP) (81%), and dissolved unreactive phosphorus (DUP) (86%). Chemical amendment of slurry did not appear to significantly increase losses of Al and Fe compared to the study control, while all amendments increased Ca loss compared to control and grass-only treatment. While chemical amendments were effective, the reductions in incidental P losses observed in this study were similar to those observed in other studies where the time from slurry application to the first rainfall event was increased. Timing of slurry application may therefore be a much more feasible way to reduce incidental P losses. Future work must examine the long-term effects of amendments on P loss to runoff and not only incidental losses.
    • Carbon cycling in temperate grassland under elevated temperature

      Jansen-Willems, Anne B.; Lanigan, Gary; Grunhage, Ludger; Muller, Christoph; Department of Agriculture, Food and the Marine, Ireland; Teagasc Walsh Fellowship Programme; RSF 10/SC/716 (Wiley, 01/11/2016)
      An increase in mean soil surface temperature has been observed over the last century, and it is predicted to further increase in the future. The effect of increased temperature on ecosystem carbon fluxes in a permanent temperate grassland was studied in a long-term (6 years) field experiment, using multiple temperature increments induced by IR lamps. Ecosystem respiration (R-eco) and net ecosystem exchange (NEE) were measured and modeled by a modified Lloyd and Taylor model including a soil moisture component for R-eco (average R2 of 0.78) and inclusion of a photosynthetic component based on temperature and radiation for NEE (R2 = 0.65). Modeled NEE values ranged between 2.3 and 5.3 kg CO2 m−2 year−1, depending on treatment. An increase of 2 or 3°C led to increased carbon losses, lowering the carbon storage potential by around 4 tonnes of C ha−1 year−1. The majority of significant NEE differences were found during night-time compared to daytime. This suggests that during daytime the increased respiration could be offset by an increase in photosynthetic uptake. This was also supported by differences in δ13C and δ18O, indicating prolonged increased photosynthetic activity associated with the higher temperature treatments. However, this increase in photosynthesis was insufficient to counteract the 24 h increase in respiration, explaining the higher CO2 emissions due to elevated temperature.
    • Effect of Agricultural Practices on Nitrate Leaching

      Ryan, M.; McNamara, K.; Brophy, Caroline; Connolly, J.; Carton, Owen T.; Richards, Karl G.; Environmental Protection Agency (Teagasc, 01/12/2005)
      A farm-scale study, carried out at Teagasc, Moorepark (Curtin’s farm), examined the effect of four managements (treatments) on nitrate-nitrogen (NO3-N) leaching over the period 2001-`05. Leaching was measured in these treatments: (T1) plots receiving dirty water and N fertilizer which were grazed; (T2) 2-cut silage and grazing plots receiving slurry and fertilizer N; (T3) grazed plots receiving fertilizer N and (T4) 1-cut silage and grazing plots receiving slurry and fertilizer N. The soil is a free-draining sandy loam overlying Karstic fissured limestone. The mean direct N inputs (kg/ha) for T1-T4 in 2001-`04 were 311, 309, 326, 331, respectively, with stocking rates (LU/ha) of 2.12 - ~2.47. Eight ceramic cups per plot, in 3 replicate plots of each treatment, were used to collect water, on a weekly basis, from 1.0 m deep using 50 kPa suction. There were 33, 37, 26 and 24 sampling dates in the 4 years, respectively. The NO3-N and NH4-N concentrations (mg/l) were determined in the water samples. The annual average and weekly concentration of these parameters was statistically analysed for all years, using a repeated measures analysis. The aggregated data were not normally distributed. There was an interaction between treatment and year (p<0.001). Significant differences (p=0.05) in NO3-N concentrations showed between the treatments in years 1, 2, 4 but not in year 3. For the NH4-N data there was no interaction between treatment and year, p=0.12, or main effect of treatment, p=0.54 but there were differences between years, p=0.01. Mean weekly concentrations were analysed separately for each year. For NO3-N, in years 1, 2 and 4 there was an interaction between treatment and week (p<0.001). With NH4-N, there was an interaction between treatment and week in all 4 years. Dirty water was significantly higher than grazed and 1 cut silage in NO3-N concentrations in year 1; in year 2, dirty water and 2 cut silage were significantly higher than the other treatments while in year 4, dirty water and grazed were significantly higher than the other two treatments. The overall four-year weighted mean NO3-N and NH4-N concentrations were 8.2 and 0.297 mg/l. The NCYCLE (UK) model was adapted for Irish conditions as NCYCLE_IRL. The NCYCLE empirical approach proved to be suitable to predict N fluxes from Irish grassland systems in most situations. Experimental data appeared to agree quite well, in most cases, with the outputs from NCYCLE_IRL. The model was not capable of predicting data from some of the leaching experiments, which suggests that the observed leaching phenomena in these experiments could be governed by non-average conditions or other parameters not accounted for in NCYCLE_IRL. An approach that took into account denitrification, leaching and herbage yield would probably explain the differences found. NCYCLE_IRL proved to be a useful tool to analyse N leaching from grazed and cut grassland systems in Ireland.
    • Surface and Groundwater Interactions: Location of a sub-surface remediation trench

      Fenton, Owen (Teagasc, 01/12/2006)
      The Water Framework Directive aims to achieve at least “good status” of all surface and groundwater bodies by 2015. In 2009 programmes of measures to achieve this status must be implemented. In 2012 water quality response to these measures will be examined at river basin catchment level. The adoption of the Water Framework Directive from the 1st January 2007 restricts the amount of nutrients which can be applied to agricultural land. A nutrient discharge to a waterbody has a negative impact on the environment and may lead to eutrophication. A broad strategy exists at European level to minimise nutrient loss to a waterbody. This strategy examines the source/pressure, pathway and receptor approach for nutrient transport. Such nutrient management strategies try to minimise nutrient loss while maintaining productivity. Nitrogen usage is now associated with environmental degradation even at lower levels than the maximum allowable concentration (11.3 mg NO3-N L-1). A further strategy proposes that nutrient management and increased utilisation of nutrients alone will fail to recognise nutrient loss even at high levels of efficiency. This strategy attempts to use remediation (Nitrate) and control technologies (Phosphorous) to intercept nutrients before discharge. Another function would be to further reduce concentrations presently at allowable levels. This introduces an interceptor phase into the nutrient transfer model.
    • Time lag: a methodology for the estimation of vertical and horizontal travel and flushing timescales to nitrate threshold concentrations in Irish aquifers

      Fenton, Owen; Schulte, Rogier P.; Jordan, Philip; Lalor, Stanley T. J.; Richards, Karl G.; Department of Environment, Heritage and Local Government; RPS Group Ltd (Elsevier Science Ltd., 02/04/2011)
      The Water Framework Directive (WFD) in Europe aims, inter alia, to achieve at least “good” water quality status by 2015 by mitigating the causes of pollution. However, with the implementation of programmes of measures in 2012, many catchments may not achieve good water quality status within this timeframe due to the time lag of nutrient transport from source to receptor via hydrological and hydrogeological pathways. An appraisal of catchment time lag issues offers a more realistic scientifically based timescale for expected water quality improvements in response to mitigation measures implemented under the WFD. A simplified methodology for the calculation of nitrate time lag in a variety of Irish hydrogeological scenarios is presented, based on unsaturated vertical and aquifer flushing times required to reach environmental quality standards. Horizontal travel time is estimated for first occurrence of nutrients in a surface water body. The results show that achievement of good water quality status in the Republic of Ireland for some waterbodies may be too optimistic within the current timeframe of 2015 targets but improvements are predicted within subsequent 6 and 12 year cycles.
    • Technical Note: Field experiences using UV/VIS sensors for high-resolution monitoring of nitrate in groundwater

      Huebsch, Manuela; Grimmeisen, F.; Zemann, M.; Fenton, Owen; Richards, Karl G.; Jordan, P.; Sawarieh, A.; Blum, P.; Goldscheider, N.; Teagasc Walsh Fellowship Programme; German Federal Ministry of Education and Research; 02WM1079-1086 (European Geosciences Union, 02/04/2015)
      Two different in situ spectrophotometers are compared that were used in the field to determine nitrate-nitrogen (NO3-N) concentrations at two distinct spring discharge sites. One sensor was a double wavelength spectrophotometer (DWS) and the other a multiple wavelength spectrophotometer (MWS). The objective of the study was to review the hardware options, determine ease of calibration, accuracy, influence of additional substances and to assess positive and negative aspects of the two sensors as well as troubleshooting and trade-offs. Both sensors are sufficient to monitor highly time-resolved NO3-N concentrations in emergent groundwater. However, the chosen path length of the sensors had a significant influence on the sensitivity and the range of detectable NO3-N. The accuracy of the calculated NO3-N concentrations of the sensors can be affected if the content of additional substances such as turbidity, organic matter, nitrite or hydrogen carbonate significantly varies after the sensors have been calibrated to a particular water matrix. The MWS offers more possibilities for calibration and error detection but requires more expertise compared with the DWS.
    • Countdown to 2010: Can we assess Ireland’s insect species diversity and loss?

      Regan, Eugenie; Nelson, Brian; McCormack, Stephen; Nash, Robert; O'Connor, James P (Royal Irish Academy, 03/09/2010)
      The insects are the most diverse organisms on this planet and play an essential role in ecosystem functioning, yet we know very little about them. In light of the Convention on Biological Diversity, this paper summarises the known insect species numbers for Ireland and questions whether this is a true refl ection of our insect diversity. The total number of known species for Ireland is 11,422. Using species accumulation curves and a comparison with the British fauna, this study shows that the Irish list is incomplete and that the actual species number is much higher. However, even with a reasonable knowledge of the species in Ireland, insects are such speciose, small, and inconspicuous animals that it is diffi cult to assess species loss. It is impossible to know at one point in time the number of insect species in Ireland and, although it is useful to summarise the known number of species, it is essential that biodiversity indicators, such as the Red List Index, are developed.
    • Ammonia emissions from cattle dung, urine and urine with dicyandiamide in a temperate grassland

      Fischer, K.; Burchill, W.; Lanigan, Gary; Kaupenjohann, M.; Chambers, B. J.; Richards, Karl G.; Forrestal, Patrick J.; Department of Agriculture, Food and the Marine, Ireland (Wiley, 03/09/2015)
      Deposition of urine and dung in pasture-based livestock production systems is a major source of ammonia (NH3) volatilization, contributing to the eutrophication and acidification of water bodies and to indirect nitrous oxide emissions. The objectives of this study were to (i) measure NH3 volatilization from dung and urine in three seasons, (ii) test the effect of spiking urine with the nitrification inhibitor dicyandiamide (DCD) on NH3 volatilization and (iii) generate NH3 emission factors (EFs) for dung, urine and urine + DCD in temperate maritime grassland. Accordingly, simulated dung, urine and urine spiked with DCD (at 30 kg DCD/ha equivalent rate) patches were applied to temperate grassland. Treatments were applied three times in 2014 with one measurement of NH3 loss being completed in spring, summer and autumn. The NH3-N EF was highest in spring, which was most likely due to the near absence of rainfall throughout the duration of loss measurement. The EFs across the experiments ranged between 2.8 and 5.3% (mean 3.9%) for dung, 8.7 and 14.9% (mean 11.2%) for urine and 9.5 and 19.5% (mean 12.9%) for urine + DCD, showing that ammonia loss from dung was significantly lower than from urine. Aggregating country-specific emission data such as those from the current experiment with data from climatically similar regions (perhaps in a weighted manner which accounts for the relative abundance of certain environmental conditions) along with modelling is a potentially resource-efficient approach for refining national ammonia inventories.