Reamonn Fealy

Making the Most of Our Land: Managing Soil Functions from Local to Continental Scale

The challenges of achieving both food security and environmental sustainability have resulted in a confluence of demands on land within the European Union (EU): we expect our land to provide food, fibre and fuel, to purify water, to sequester carbon, and provide a home to biodiversity as well as external nutrients in the form of waste from humans and intensive livestock enterprises. All soils can perform all of these five functions, but some soils are better at supplying selective functions. Functional Land Management is a framework for policy-making aimed at meeting these demands by incentivising land use and soil management practices that selectively augment specific soil functions, where required. Here, we explore how the demands for contrasting soil functions, as framed by EU policies, may apply to very different spatial scales, from local to continental scales. At the same time, using Ireland as a national case study, we show that the supply of each soil function is largely determined by local soil and land use conditions, with large variations at both local and regional scales. These discrepancies between the scales at which the demands and supply of soil functions are manifested, have implications for soil and land management: while some soil functions must be managed at local (e.g. farm or field) scale, others may be offset between regions with a view to solely meeting national or continental demands. In order to facilitate the optimisation of the delivery of soil functions at national level, to meet the demands that are framed at continental scale, we identify and categorise 14 policy and market instruments that are available in the EU. The results from this inventory imply that there may be no need for the introduction of new specific instruments to aid the governance of Functional Land Management. We conclude that there may be more merit in adapting existing governance instruments by facilitating differentiation between soils and landscapes.

Estimating the effects of land use at different scales on high ecological status in Irish rivers

High ecological status at river sites is an indicator of minimal disturbance from anthropogenic activities and the presence of ecologically important species and communities. However, a lack of clarity on what factors cause sites to lose high ecological status is limiting the ability to maintain the quality of these sites. Examination of ecological status records at 508 high status river sites throughout the Republic of Ireland revealed that 337 had fallen below high status at some point between 2001 and 2012 due to changes in invertebrate communities. A geographical information system was used to characterise land use and environmental variables in the catchment, riparian and reach areas upstream of the sites. The relationships between these variables at the three spatial scales and whether or not river sites had maintained high ecological status were then estimated by multiple logistic regression and propensity modelling. The results indicated that grassland at either catchment or riparian scales had a greater negative impact on high ecological status than at the reach scale. This effect appeared to be strongest for upland, steeply sloping rivers that are subject to high rainfall, possibly due to the presence of sensitive biota and/or a greater potential for erosion. These results highlighted the need for better management of grassland upstream of the high status sites, with a focus on river alterations and critical source areas of nutrients, sediments and pesticides that are hydrologically connected to the river. Sustainable management practices and land use planning in those areas will need to be considered carefully if the aim of maintaining high ecological status at river sites is to be achieved.

The Irish Forest Soils Project and its Potential Contribution to the Assessment of Biodiversity

The United Nations Environment Programme (UNEP) has proposed methods and thematic areas for data collection that are appropriate to the evaluation of biodiversity. The Heritage Council has identified a paucity of data on habitats in Ireland. Within this context, we outline the Irish Forest Soils (IFS) element of the Forest Inventory and Planning System (FIPS) and present a detailed account of land-cover mapping, which is an important aspect of the project. The IFS project aims to produce a national thematic map of land cover using soft-copy photogrammetry, combined with satellite-image classification and field survey. This aspect of the IFS project generates data on land cover at different spatial and classification resolutions. We report on the progress made to date and present illustrative examples of the data sets. The UNEP proposals provide a useful framework within which to discuss the potential contribution of IFS data to the assessment of biodiversity.

Simulation of soil carbon efflux from an arable soil using the ECOSSE model: Need for an improved model evaluation framework?

Globally, it is estimated that ~1500PgC of organic carbon is stored in the top meter of terrestrial soils. This represents the largest terrestrial pool of carbon. Appropriate management of soils, to maintain or increase the soil carbon pool, represents a significant climate change mitigation opportunity. To achieve this, appropriate tools and models are required in order to more accurately estimate soil carbon fluxes with a view to informing and developing more effective land use management strategies. Central to this is the evaluation of models currently in use to estimate soil carbon emissions. In the present study, we evaluate the ECOSSE (Estimating Carbon in Organic Soils - Sequestration and Emissions) model which has its origins in both SUNDIAL and RothC and has been widely used globally to model soil CO2 fluxes across different locations and land-use types on both organic and mineral soils. In contrast to previous studies, the model was found to poorly represent observed soil respiration at the study site, an arable cropland on mineral soil located in south-east Ireland. To isolate potential sources of error, the model was decomposed into its component rate equations or modifiers. This investigation highlighted a deficiency in the model simulated soil water, resulting in significant inhibition of the model simulated CO2 flux relative to the observed data. When measured values of soil water at the site were employed, the model simulated soil respiration improved significantly (r2 of 0.775 vs 0.154). This highlighted model deficiency remains to be evaluated at other sites; however, the research highlights the need for a more comprehensive evaluation of soil carbon models prior to their use in informing policy, particularly models which are employed at larger scales and for climate change projections.

A History of Soil Research with Emphasis on Pedology

While commentary on the productivity of Irish pastures can be dated as far back as 55 BC, direct references to the different kinds of soil only begin in the eighth century AD. Early scientific information on Irish soils typically came from the endeavours of geologists or other professionals who studied rock and outcropping patterns. The Geological Survey of Ireland, a constituent of the Geological Survey of Great Britain and Ireland, developed small-scale county soil maps, largely for the southern counties in the mid-1800s. In relation to pedology, John Hodges, an Irish soil analyst described soil profiles in the 1850s in terms identical with those dated to the Dokuchaev School in 1880s Russia. Soil science in Ireland has typically been delivered with agricultural and environmental science at University level. Agricultural extension dates back to 1731 through the Dublin Society employment of itinerant instructors. The soil test, pioneered by P H Gallagher in the 1930s became the single most important tool for the advisory service. In their essays on the characteristics of Irish soil types he, together with Dr. Tom Walsh, laid the groundwork for future classification and mapping. In 1945, the Department of Agriculture established a research centre at Johnstown Castle, Co. Wexford. The soil division of An Foras Taluntais was headquartered there and the National Soil Survey of Ireland established. In 1980 the second edition, General Soil Map of Ireland, was published. This survey was discontinued in 1988. In 1998, the Spatial Analysis Unit was established in Teagasc a key output of which was the first nationally complete digital subsoil and indicative soil map in 2009. Not long after, the 3rd Edition National Soil Map of Ireland was launched in 2014, through the collaboration of the Spatial Analysis Unit and Teagasc Johnstown Castle.

Soil Geography and Development of the Third Edition National Soil Map

The geography of the soils of Ireland in relation to the distribution of Great Soil Groups, the distinct Soil Subgroups that occur within each Great Soil Group and a reference profile description at series level from the online SIS database are presented in this chapter. This follows with a description of the development of the 3rd Edition National Soil Map of Ireland. Prior to the Irish Soil Information Systems (SIS) project, systematic pedology in Ireland had largely been related to mapping exercises, such as the previous National Soil Survey (NSS) conducted by An Foras Taluntais (AFT) who mapped 44% of the country at a scale of 1:126,720; developed a General Soil Map of Ireland and a National Peatland map, both at 1:575,000 scale. In 2009 the Irish SIS project was established to bring together all existing pedological data and map the remaining land area. A scale of 1:250,000 was determined as appropriate for the development of the 3rd Edition National Soil Map of Ireland based on recommendations of the European Soil Bureau Network (ESBN) Technical Working Group responsible for soil monitoring and harmonisation. The 1:250,000 national soil map of Ireland is a soil map composed of soil associations of the 213 soil series, and altogether a total of 58 soil associations, excluding peat, alluvium, urban, rock and marsh, are defined. A harmonisation of legacy data (Terra Cognita) was completed and served as the basis for the generation of soil-landscape models which were then used to model areas where detailed soil surveys had not previously been carried out. Validation of this methodology was carried out over a 2.5-year field survey, in which 11,000 locations were assessed for soil type using an auger survey approach. Where previously unidentified combinations of soilscape units were found, soil profile pits were excavated, sampled and described at representative locations across the country to define this new soil information. These 225 pits were described and sampled in detail and were used to support the development of a new soil classification (described in Chap. 3).

Developing regional calibration coefficients for estimation of hourly global solar radiation in Ireland

ABSTRACT This study proposed regional coefficients for estimating hourly global solar radiation through the adaptation of some empirical models that relate radiation to climatological and geographical variables. A total of 10 models were adapted over 7 stations in Ireland. The performance of the models was evaluated using some selected error indicators including the global performance index which combines all other error indices. The results indicated that the sunshine based regional calibration coefficients generated through a polynomial approach was most superior over other models with the lowest RMSE (0.2–0.3 MJm−2 hr−1), MAE (0.1–0.2 MJm−2 hr−1) and Pbias (0–7.0%) and highest R2 and KGE (>0.85). The study found no local effect such as instrumental siting, observational uncertainty and climate on the variations of these coefficients. This outcome will therefore facilitate the design of various local and/or regional solar energy applications at microscale in a temperate region.

Assessment of water-limited winter wheat yield potential at spatially contrasting sites in Ireland using a simple growth and development model

Abstract Although Irish winter wheat yields are among the highest globally, increases in the profitability of this crop are required to maintain its economic viability. However, in order to determine if efforts to further increase Irish wheat yields are likely to be successful, an accurate estimation of the yield potential is required for different regions within Ireland. A winter wheat yield potential model (WWYPM) was developed, which estimates the maximum water-limited yield achievable, within the confines of current genetic resources and technologies, using parameters for winter wheat growth and development observed recently in Ireland and a minor amount of daily meteorological input (maximum and minimum daily temperature, total daily rainfall and total daily incident radiation). The WWYPM is composed of three processes: (i) an estimation of potential green area index, (ii) an estimation of light interception and biomass accumulation and (iii) an estimation of biomass partitioning to grain yield. Model validation indicated that WWYPM estimations of water-limited yield potential (YPw) were significantly related to maximum yields recorded in variety evaluation trials as well as regional average and maximum farm yields, reflecting the model’s sensitivity to alterations in the climatic environment with spatial and seasonal variations. Simulations of YPw for long-term average weather data at 12 sites located at spatially contrasting regions of Ireland indicated that the typical YPw varied between 15.6 and 17.9 t/ha, with a mean of 16.7 t/ha at 15% moisture content. These results indicate that the majority of sites in Ireland have the potential to grow high-yielding crops of winter wheat when the effects of very high rainfall and other stresses such as disease incidence and nutrient deficits are not considered.