• Application of Dexter’s soil physical quality index: an Irish case study

      Fenton, Owen; Vero, Sara E.; Schulte, Rogier P.; O'Sullivan, Lilian; Bondi, G.; Creamer, Rachel E.; Department of Agriculture, Food and the Marine, Ireland; 6582 (Teagasc (Agriculture and Food Development Authority), Ireland, 26/08/2017)
      Historically, due to a lack of measured soil physical data, the quality of Irish soils was relatively unknown. Herein, we investigate the physical quality of the national representative profiles of Co. Waterford. To do this, the soil physical quality (SPQ) S-Index, as described by Dexter (2004a,b,c) using the S-theory (which seeks the inflection point of a soil water retention curve [SWRC]), is used. This can be determined using simple (S-Indirect) or complex (S-Direct) soil physical data streams. Both are achievable using existing data for the County Waterford profiles, but until now, the suitability of this S-Index for Irish soils has never been tested. Indirect-S provides a generic characterisation of SPQ for a particular soil horizon, using simplified and modelled information (e.g. texture and SWRC derived from pedo-transfer functions), whereas Direct-S provides more complex site-specific information (e.g. texture and SWRC measured in the laboratory), which relates to properties measured for that exact soil horizon. Results showed a significant correlation between S-Indirect (Si) and S-Direct (Sd). Therefore, the S-Index can be used in Irish soils and presents opportunities for the use of Si at the national scale. Outlier horizons contained >6% organic carbon (OC) and bulk density (Bd) values <1 g/cm3 and were not suitable for Si estimation. In addition, the S-Index did not perform well on excessively drained soils. Overall correlations of Si. with Bd and of Si. with OC% for the dataset were detected. Future work should extend this approach to the national scale dataset in the Irish Soil Information System.
    • Exploring the sensitivity of visual soil evaluation to traffic-induced soil compaction

      Emmet-Booth, J.P.; Holden, N.M.; Fenton, Owen; Bondi, G; Forristal, P.D.; Irish Department of Agriculture, Food and the Marine; 13/S/468 (Elsevier, 2019-10-24)
      Visual Soil Evaluation (VSE) techniques are useful for assessing the impact of land management, particularly the identification and remediation of soil compaction. Despite an increasing body of VSE research, comparatively few studies have explored the sensitivity of VSE for capturing experimentally imposed compaction to estimate sensitivity and limit of detection. The aim of this research was to examine the ability of VSE techniques to indicate soil structure at different soil profile depths and to measure the associated soil productive function (yield) response to imposed compaction. A two-year experiment was conducted on sites with loam and sandy soils. Varying levels of wheeled traffic were imposed on plots in a randomised block design, prior to sowing winter barley (Hordeum vulgare L.). Quantitative crop and soil measurements were taken throughout the season in conjunction with VSE techniques, which assessed to 25 cm (VESS), 40 cm (Double Spade) and 80 cm (SubVESS) depth. Graduated changes were observed by soil and some crop quantitative measurements as traffic treatment varied. VESS and Double Spade successfully identified a graduated treatment effect at all sites to 40 cm depth, although diagnosis translated into a yield response for the loam but not the sandy soil. Correlation between VESS Sq scores and crop yield were found. SubVESS gave mixed signals and indicated impacts lower in the profile in certain instances. These impacts were not captured by quantitative soil measurements.This work highlights the capacity for VSE techniques to indicate soil structural damage, which may cause a crop yield response, therefore allowing appropriate soil management strategies to be deployed before yield penalties occur.
    • Functional land management: A framework for managing soil-based ecosystem services for the sustainable intensification of agriculture

      Schulte, Rogier P.; Creamer, Rachel; Donnellan, Trevor; Farrelly, Niall; Fealy, Reamonn; O’Donoghue, Cathal; O’hUallachain, Daire (Elsevier, 2013-11-20)
      Sustainable 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.
    • Implications of the proposed Soil Framework Directive on agricultural systems in Atlantic Europe – a review

      Creamer, Rachel E.; Brennan, Fiona P.; Fenton, Owen; Healy, Mark G.; Lalor, Stanley T. J.; Lanigan, Gary; Regan, J. T.; Griffiths, Bryan (Wiley; British Society of Soil Science, 28/07/2010)
      The main threats to soils outlined in the pending Soil Framework Directive (SFD) are: contamination, loss of organic matter, erosion, compaction, sealing, salinization and desertification. The first four threats are pertinent to agricultural systems in Atlantic Europe, but vary in their extent between countries depending on the spatial soil distribution. Loss of soil biodiversity has not been included as a potential threat in the SFD due to lack of information that is currently available both spatially and temporally to facilitate any legislation to protect it. This paper gives emphasis to the four main threats outlined above associated with Agricultural systems in Atlantic Europe. Each soil threat is discussed in relation to the agricultural management calendar for cultivated and grazed grassland soils. The paper discusses current soil protection policies and possible changes to such legislation with the adoption of the SFD by member states.
    • The Potential Economic Returns of Converting Agricultural Land to Forestry: An Analysis of System and Soil Effects from 1995 to 2009

      Upton, Vincent; Ryan, Mary; Farrelly, Niall; O'Donoghue, Cathal; Department of Agriculture, Food and the Marine, Ireland (Society of Irish Foresters, 05/07/2013)
      Private land owners have been responsible for the majority of annual afforestation in Ireland since the mid1990s, but planting rates have generally been declining since 2002. Although the decision to plant may be driven by a number of factors, the profitability of forestry as a landuse option should be an important driver and offer some insight into trends in afforestation rates. As farmers undertake most afforestation in Ireland it is important to account for the opportunity cost of lost agricultural income when analysing the financial outcome of planting. In addition, soil quality plays an essential role in dictating the productivity and profitability of both agriculture and forestry. This study examines the effects of soil quality and superseded agricultural system on the potential profitability of afforestation by farmers between 1995 and 2009. Data from the National Farm Survey were employed to identify the annual gross margins for six agricultural systems on six soil types that differ in terms of quality. The measures of soil quality were translated into potential yield classes for forestry using an existing productivity model and Teagasc’s Forest Investment and Valuation Estimator was employed to calculate the net present value of afforestation for each of the systems and soil types. The results demonstrate how the competitiveness of forestry as a landuse option is influenced by soil quality and superseded enterprise and how forestry has become more competitive with agricultural enterprises over the period of analysis.
    • A review of phosphorus and sediment release from Irish tillage soils, the methods used to quantify losses and the current state of mitigation practice

      Regan, J. T.; Fenton, Owen; Healy, Mark G.; Teagasc Walsh Fellowship Programme (Royal Irish Academy, 20/03/2012)
      Throughout the European Union (EU), agricultural soils with high phosphorus (P) status due to surplus fertiliser input have been identifi ed as a landscape pressure impacting on water quality. In Republic of Ireland, approximately 80% of agricultural land is devoted to grass, 11% to rough grazing, and 9% to arable cereal and crop production. Consequently, the majority of erosion research has focused on quantifying nutrient and sediment losses from grassland. Tillage soils are, however, more susceptible to erosion than grassland soils and, in general, have higher levels of soil P. This paper reviews the current state of research and the regulatory regime relating to diffuse P and sediment loss for tillage soils. It identifi es the key threats to soil quality associated with cultivated soils, and proposes the targeting and remediation of critical source areas for effective mitigation of P losses from tillage soils. A multiscaled approach is recommended, in which catchment and field-scale monitoring is complemented with controlled laboratory and small plot-scale rainfall simulation experiments to identify areas where P loss and soil erosion are at critical levels and may pose a threat to water quality. Catchment scale research will help to link critical source areas of sediment and P loss with hydrological pathways to surface waters in the catchment area. These areas can then be targeted for remediation in the river basin management plans.