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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

The implementation of site-specific land drainage system designs is usually disregarded by landowners in favour of locally established ‘standard practice’ land drainage designs. This is due to a number of factors such as a limited understanding of soil–water interactions, lack of facilities for the measurement of soil’s physical or hydrological parameters and perceived time wastage and high costs. Hence there is a need for a site-specific drainage system design methodology that does not rely on inaccessible, time-consuming and/or expensive measurements of soil physical or hydrological properties. This requires a standardised process for deciphering the drainage characteristics of a given soil in the field. As an initial step, a new visual soil assessment method, referred to as visual drainage assessment (VDA), is presented whereby an approximation of the permeability of specific soil horizons is made using seven indicators (water seepage, pan layers, texture, porosity, consistence, stone content and root development) to provide a basis for the design of a site-specific drainage system. Across six poorly drained sites (1.3 ha to 2.6 ha in size) in south-west Ireland a VDA-based design was compared with (i) an ideal design (utilising soil physical measurements to elucidate soil hydraulic parameters) and (ii) a standard design (0.8 m deep drains at a 15 m spacing) by model estimate of water table control and rainfall recharge/drain discharge capacity. The VDA method, unlike standard design equivalents, provided a good approximation of an ideal (from measured hydrological properties) design and prescribed an equivalent land drainage system in the field. Mean modelled rainfall recharge/drain discharge capacity for the VDA (13.3 mm/day) and ideal (12.0 mm/day) designs were significantly higher (P < 0.001, s.e. 1.42 mm/day) than for the standard designs (0.5 mm/day), when assuming a design minimum water table depth of 0.45 m.

Heavy drinking remains prevalent and problematic on college campuses. 'Open-Label Placebos' (OLPs) have gained recent attention as interventions for various disorders. The current aim was to carry out two feasibility studies of OLP interventions for college students. In Study 1, of-age students readily consumed the fake alcohol, and experienced slight beneficial effects (N=26). In Study 2, our enhanced OLP intervention for underage students backfired; we increased, rather than decreased, their intentions to drink real alcohol (N=83). The underage students most commonly reported wanting alcohol to ease social discomfort, and perhaps felt that the OLP left their wishes unanswered. Overall, the results suggest that OLP research should be approached with caution. Filtered prompts and behavioral experiments might re-direct and strengthen outcomes. Keywords: alcohol, open-label placebo, college, Heavy drinking has continued to be prevalent and problematic on college campuses for at least forty years (Schulenberg, Patrick, Johnston, O'Malley, Bacnman & Miech, 2021). Far from a benign rite [...]

Introduction: On intensive grassland dairy farms in high rainfall areas with poorly drained soils, networks of open drainage channels linked to in-field drainage systems are needed to enable farm operations. Nitrogen and phosphorus point and diffuse sources may be connected to this open drainage channel network along surface and subsurface pathways, with negative impacts upon delivery to the downstream aquatic system. Methods: This study developed a semi-quantitative risk assessment model by: (1) selecting parameters (categorical or continuous) representing the nutrient transfer continuum and (2) scoring (relative magnitude and impact) the risk of nutrient source connectivity and delivery for every open drainage channel section across seven dairy farms. Results and Discussion: A Risk Index Classification System consisting of low, medium, high, or very high-risk class was developed, with high or above requiring a mitigation plan. Results showed that 23%, 68%, 9% and 0% of all open drainage channels on study farms were identified as low, moderate, high and very highrisk, respectively. A range from 2% to 25% per farm of the open drainage channels was classified as high-risk that potentially needed mitigation, although none was identified as very high-risk. Two-thirds of the high-risk open drainage channels were connected to the farmyards, with potential for high nutrient loss from point sources. A combined approach of source management and targeted breaking of the pathway (e.g., in-channel filters, water diversion bars) may help minimise nutrient losses from high risk open drainage channels on poorly draining soils. [ABSTRACT FROM AUTHOR]

Soil quality determines the ability of soil to deliver ecosystem services and can be inferred from physical, biological and chemical indicators either in isolation or in combination. Earthworms are good soil-quality indicators that contribute to both chemical and physical quality by maintaining soil structure and cycling nutrients. The presence of dung pats can increase earthworm abundance locally and consequently the network of pores that they create through their burrowing activity. Inevitably this affects soil structure and consequently will have a spatially distributed effect on soil physical quality (SPQ). The aim of this field study was to examine the relationship between SPQ and earthworm abundance under dung and non-dung pat areas from deposition to decay and beyond. The present spatial and temporal study compared SPQ indicator (integral air-water energy, [AW.sub.r]) results with earthworm abundance across control and simulated dung pat treatments. Results showed that existing earthworm populations in this grassland were already very large (>500 individuals [m.sup.-2]) and SPQ ([AW.sub.r]) remained in the 'very good' category throughout the experiment. Earthworm abundance under dung pats and SPQ exhibited a significant (P = 0.05) temporal trend. In general, the time of decay of the dung pats played a role in increasing earthworm abundance and SPQ. Earthworm abundance and macropore density data formed a similar, 'hump'-shaped dynamic over time. However, when an earthworm abundance threshold was exceeded (equivalent to about >3000 individuals [m.sup.-2]), the increase of SPQ under dung was attenuated and did increase further only under the control sward with high earthworm abundance. After 11 weeks, for both treatments, [AW.sub.r] under dung pats was capped at 0.83% and AW, under control sward peaked at 1.34%. Future work should focus on (a) further exploration of the threshold where earthworm abundance becomes detrimental for SPQ and (b) using the [AW.sub.r] SPQ indicator within an actual grazed trial which incorporates a gradient of soil degradation. Additional keywords: dung decomposition, earthworms, grassland, grazing, physical soil properties. Received 5 November 2019, accepted 17 April 2020, published online 3 June 2020, Introduction Soil quality reflects the ability of soil to deliver a range of provisioning, regulating, supporting and cultural services (Schulte et al. 2014). The development of soil quality indicators must [...]