The spatial variation in degree days derived from locational attributes for the 1961 to 1990 period

peer-reviewedThe relationship between degree days and locational attributes for a selection of sites in Ireland were examined in order to objectively extrapolate values for unmeasured locations. While a number of previous researchers have employed similar methodologies in order to map the geographical variation for selected degree-day thresholds, the authors seek to expand on this existing research through the inclusion of a denser network of stations and for a longer time period (1961 to 1990). Degree days were calculated on a daily basis for three selected threshold temperatures, 0 oC, 5 oC, 10 oC, in order to provide a more accurate assessment of the accumulated monthly energy available at each station. The geographical distribution of degree days was then mapped employing a stepwise linear regression which related locational parameters for each station to the calculated monthly accumulations. While none of the selected thresholds are specific to any plant or insect species they are indicative of the likely spatial variation in degree days due to location and elevation. It is intended that the derived spatial distributions will be useful in providing a basis for assessing likely changes in the thermal regime arising as a consequence of climate change over the course of the present century with the associated potential impact on spatial location of arable cropping in Ireland.The authors gratefully acknowledge the financial support provided by the Irish Environmental Protection Agency, as part of the Environmental RTDI Programme 2000–2006

Modelling the Gross Cost of Transporting Pig Slurry to Tillage Spread Lands in a Post Transition Arrangement within the Nitrates Directive.

working paperThe context of this paper is in the phasing out of the transitional arrangement under the Nitrates Directive. As there is relatively little grassland capable of taking significant amounts of pig slurry available in the vicinity of the main pig production areas, in this paper we attempt to quantify the cost of transporting this slurry to the nearest available tillage land. The approach taken was to examine the geographic structure underlying the pig sector in Ireland using Geographic Information Systems (GIS) technology. The study highlighted the differential cost with, amounting to 10% of gross margin on average and as high in major pig producing areas as 21.5% in Longford and 16.6% in Cavan, while lower at 7-9% in South Tipperary and Cork. Thus while the problem is significant, the impact is not constant across the country, highlighting the value of a spatial analytical approach. Future work should assess the existing cost of spreading manure in order to be able to ascertain the net cost of spreading on tillage lands. The robustness of the results also need to be tested to assess the implications of changes in the prices of fossil fuels and fertilisers, both in terms of the cost function and in terms of the cost of substitutable mineral fertilise

A model framework to investigate the role of anomalous land surface processes in the amplification of summer drought across Ireland during 2018

Due to its latitude and ample year-round rainfall, Ireland is typically an energy-limited regime in the context of soil moisture availability and evapotranspiration. However, during the summer of 2018, regions within the country displayed significant soil moisture deficits, associated with anomalous atmospheric forcing conditions, with consequent impacts on the surface energy balance. Here, we explore the utility of a physically based land surface scheme coupled with observational, global gridded reanalysis and satellite derived data products to analyse the spatial and temporal evolution of the 2018 summer drought event in Ireland over grassland, which represents the dominant agricultural land-cover. While the surface–air energy exchanges were initially dominated by atmospheric anomalies, soil moisture constraints became increasingly important in regulating these exchanges, as the accumulated rainfall deficit increased throughout the summer months. This was particularly evident over the freer draining soils in the east and southeast of the country. From late June 2018, we identify a strong linear coupling between soil moisture and both evapotranspiration and vegetation response, suggesting a shift from an energy-limited evapotranspiration regime into a dry or soil water limited regime. Applying segmented regression models, the study quantifies a critical soil moisture threshold as a key determinant of the transition from wet to dry evaporative regimes. These findings are important to understand the soil moisture context under which land–atmosphere couplings are strongest in water-limited regimes across the country and should help improve the treatment of soil parameters in weather prediction models, required for subseasonal and seasonal forecasts, consequently enhancing early warning systems of summer climate extremes in the future

Improving a land surface scheme for estimating sensible and latent heat fluxes above grasslands with contrasting soil moisture zones

peer-reviewedKnowledge of soil–vegetation–atmosphere energy exchange processes is essential for examining the response of agriculture to changes in climate in both the short and long term. However, there are relatively few sites where all the flux measurements necessary for evaluating these responses are available; where they exist, data are often incomplete and/or of limited duration. At the same time, there is often an extensive observation network available that has gathered key meteorological data (sunshine, wind, rainfall, etc.) over decades. Simulating the terms of the surface energy balance (SEB) using available meteorological, soil and vegetation data can improve our understanding of how agricultural systems respond to climate and how this response will vary spatially. Here, we employ a physically-based scheme to simulate the SEB fluxes over a mid-latitude, maritime temperate environment using routine weather observations. The latent heat flux is a critical SEB term as it incorporates the response of the plant to environmental conditions including available energy and soil water. This response is represented in modeling schemes through surface resistance (rs), which is usually expressed as a function of near-surface water vapor alone. In this study, we simulate the SEB over two grassland sites, where eddy flux observations are available, representing imperfectly- and poorly- drained soils. We employ three different formulations of rs, representing varying degrees of sophistication, to estimate the surface fluxes. Due to differences in soil moisture characteristics between the sites, we ultimately focused our attention on an rs formulation that accounted for soil water retention capacity, based on the Jarvis conductance model; the results at both hourly and daily intervals are in good agreement, with RMSE values of ≈ 40 W m−2 for sensible and latent heat fluxes at both sites. The findings show the potential value of using routine weather observations to generate the SEB where flux observations are not available and the importance of soil properties in estimating surface fluxes. These findings could contribute to the assessment of past and future climate change on grassland ecosystems

Improving a land surface scheme for estimating sensible and latent heat fluxes above grasslands with contrasting soil moisture zones

Knowledge of soil–vegetation–atmosphere energy exchange processes is essential for examining the response of agriculture to changes in climate in both the short and long term. However, there are relatively few sites where all the flux measurements necessary for evaluating these responses are available; where they exist, data are often incomplete and/or of limited duration. At the same time, there is often an extensive observation network available that has gathered key meteorological data (sunshine, wind, rainfall, etc.) over decades. Simulating the terms of the surface energy balance (SEB) using available meteorological, soil and vegetation data can improve our understanding of how agricultural systems respond to climate and how this response will vary spatially. Here, we employ a physically-based scheme to simulate the SEB fluxes over a mid-latitude, maritime temperate environment using routine weather observations. The latent heat flux is a critical SEB term as it incorporates the response of the plant to environmental conditions including available energy and soil water. This response is represented in modelling schemes through surface resistance (rs), which is usually expressed as a function of nearsurface water vapor alone. In this study, we simulate the SEB over two grassland sites, where eddy flux observations are available, representing imperfectly- and poorly- drained soils. We employ three different formulations of rs, representing varying degrees of sophistication, to estimate the surface fluxes. Due to differences in soil moisture characteristics between the sites, we ultimately focused our attention on an rs formulation that accounted for soil water retention capacity, based on the Jarvis conductance model; the results at both hourly and daily intervals are in good agreement, with RMSE values of ≈ 40 W m−2 for sensible and latent heat fluxes at both sites. The findings show the potential value of using routine weather observations to generate the SEB where flux observations are not available and the importance of soil properties in estimating surface fluxes. These findings could contribute to the assessment of past and future climate change on grassland ecosystems

Functional land management: A framework for managing soil-based ecosystem services for the sustainable intensification of agriculture

peer-reviewedSustainable food production has re-emerged at the top of the global policy agenda, driven by two challenges: (1) the challenge to produce enough food to feed a growing world population and (2) the challenge to make more efficient and prudent use of the world's natural resources. These challenges have led to a societal expectation that the agricultural sector increase productivity, and at the same time provide environmental ‘ecosystem services’ such as the provision of clean water, air, habitats for biodiversity, recycling of nutrients and mitigation against climate change. Whilst the degree to which agriculture can provide individual ecosystem services has been well researched, it is unclear how and to what extent agriculture can meet all expectations relating to environmental sustainability simultaneously, whilst increasing the quantity of food outputs. In this paper, we present a conceptual framework for the quantification of the ‘supply of’ and ‘demand for’ agricultural, soil-based ecosystem services or ‘soil functions’. We use Irish agriculture as a case-study for this framework, using proxy-indicators to determine the demand for individual soil functions, as set by agri-environmental policies, as well as the supply of soil functions, as defined by land use and soil type. We subsequently discuss how this functionality of soils can be managed or incentivised through policy measures, with a view to minimising the divergence between agronomic policies designed to promote increased agricultural production and environmental policy objectives. Finally, we discuss the applicability of this conceptual framework to agriculture and agri-environmental policies at EU level, and the implications for policy makers

phenModel: A temperature-dependent phenology/voltinism model for a herbivorous insect incorporating facultative diapause and budburst

A comprehensive phenology/voltinism model was developed for Phratora vulgatissima, an important pest of bioenergy crops. The model, phenModel, was developed based on development times of different life cycle stages (eggs, larvae, pupae, pre-oviposition, oviposition, sexual maturation) obtained from constant temperature laboratory experiments. As part of this study, a number of linear and non-linear models which describe the temperature-dependent development rate (inverse of development time) for each of the different life cycle stages were fitted. Based on the criteria of model parsimony and model fit, the non-linear Lactin-2 model was chosen as the optimum model to describe temperature-driven development in P. vulgatissima. To account for the variation in development times between individuals, an important but often ignored aspect in phenology models, a number of stochastic models (2- and 3- parameter Weibull and logistic models) were evaluated, based on the assumption that normalised development times conform to a similar shaped ('same shape') distribution. Novel aspects of the phenology model include the incorporation of a biologically relevant biofix, based on a budburst model for Salix viminalis, and a photoperiod threshold to induce facultative diapause. The model, which is written in R for accessibility, requires inputs of daily minimum and maximum temperature and site latitude and produces outputs describing the timing of completion of developmental stages for specified proportions of the population. It was evaluated against available field data and found to largely reproduce the observations providing a measure of its potential utility. A key component of the model allows for a sensitivity analysis of the model parameters. The model is structured so that it can easily be adapted for other leaf-feeding beetles which display a facultative reproductive diapause cued by photoperiod, and where the onset of oviposition is dependent on budburst, assuming relevant life cycle stage parameters are available

Digital Soil Mapping in the Irish Soil Information System

Harmonised soil data across Europe with a 1:250 000 geo-referenced soil database will allow for exchange of data across member states and the provide the information needed by the European Commission and European Environment Agency for reporting on issues relating to soil quality under a fu-ture Soil Framework Directive. Within this context, the Environmental Protection Agency of the Republic of Ireland commissioned a project run by Teagasc to produce a 1:250 000 soil map of the Republic of Ire-land. Delivery of this map and associated database is a collaborative effort between Teagasc, the National Soil Resources Institute at Cranfield in the UK and University College Dublin.Environmental Protection Agenc

A Response to the Draft Climate Change Adaptation Sectoral Plan for Agriculture, Forest and Seafood Sector

Teagasc is pleased to have the opportunity to contribute to this Draft Climate Change Adaptation Sectoral Plan for Agriculture, Forest and Seafood Sectors, although our contribution will largely be limited to the agriculture and forestry sectors. We have also taken the liberty to contribute in the form of ‘submissions, observations and comments’ as indicated in the call for contributions rather than in the formal questionnaire which appears to be more appropriate for an individual submission rather than an organisational contribution

Mapping Soils in Ireland

peer-reviewedThis project is jointly funded by Teagasc and EPA STRIVE funding.Harmonised soil data across Europe with a 1:250 000 geo-referenced soil database will allow for exchange of data across member states and the provide the information needed for reporting on issues re-lating to soil quality under a future Soil Framework Directive. The current status of soils data available in Eu-rope is inconsistent at best. The Irish Soil Information System (ISIS) project is currently developing a national soil map of 1:250,000 and an associated digital soil information system, providing both spatial and quantita-tive information on soil types and properties across Ireland. Both the map and the information system will be freely available to the public through a designated website.This project is jointly funded by Teagasc and EPA STRIVE funding