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Photosystem II (PS II) pesticides, recognised as a threat to ecological health, were targeted for reduction in sugarcane farming in the Great Barrier Reef (GBR) catchments. Alternative herbicides, the non-PS II herbicides (including glyphosate, paraquat, 2,4-D, imazapic, isoxaflutole, metolachlor, and S-metolachlor), continue to be used in these catchments. However, the potential ecological fate, transport, and off-site environmental effects of non-PS II herbicides, with respect to their usage scheme, local rainfall patterns, and infiltration dynamics, has not been investigated previously. A vadose zone monitoring system, instrumented beneath a sugarcane land in a GBR catchment, was applied for real time tracing of pesticide migration across the unsaturated zone, past the root zone during 2017–2019.The monitoring of regularly applied pesticides (fluroxypyr and isoxaflutole), exhibited substantial migration through the unsaturated zone. Within one month after application of fluroxypyr, it leached to 2.87 m depth in the vadose zone, with declining concentrations with depth. Isoxaflutole, which was applied yearly, was found only once, in November 2018, at 3.28 m depth in the soil profile. Other pesticides (imazapic, metolachlor, glyphosate and haloxyfop), applied at the same period, were not detected through the vadose zone. However, imidacloprid, which was not applied at the site during the monitored period, was detected across the entire vadose zone, revealing substantial resistance to degradation. The results show no evidence of any regularly applied pesticides in the site bores at the end of the study, indicating their ultimate degradation within the vadose zone before reaching the groundwater.

One aspect of the NHS Long Term Plan is to establish a more comprehensive community-based mental health crisis response. NHS trusts have therefore looked to new services to help alleviate in-patient bed pressures. Intensive Outpatient Programmes (IOPs) have been previously used to help support people living with substance-misuse or eating disorders. More recently IOPs have been utilised to support people living with depression and anxiety. The Acute Community Service (ACS) was established as an IOP to support older adults in crisis by providing psychological, nursing, occupational, and physiotherapy interventions. Initial findings are consistent with previous research showing significant improvements in mood, levels of anxiety, and quality of life, with some service users being suitable for discharge to primary care. The ACS looks to build on these promising findings by working towards understanding the impact of the service on the frequency and length of in-patient admissions. Additionally, we would aim to understand the longer term impact of the ACS on service users and re-referrals rates.

Around half a million people are in residential care in the UK, with estimates suggesting 80 per cent have dementia. Behaviours that challenge which commonly occur in people with dementia are difficult for care home staff, many of whom have no direct career paths and limited training opportunities, to understand and manage. We designed a dementia training package which involved four modules and took two and a half hours to deliver. This training package was trialled into six care homes in Kingston-Upon-Hull who had been regular referrers into secondary mental health care. In total, 123 care home staff attended the training and feedback was very positive with 100 per cent of participants agreeing that the training was useful for their development, they learnt new knowledge and could apply their learning. We additionally collected qualitative data from care home staff on the content of the training. There was a 54 per cent reduction in total referrals to the local community mental health team in the 12-months post-training compared to the 12-months preceding. We discuss challenges to implementing the training during the Covid-19 pandemic as well as consider potential future developments.

Tamborine Mountain, Queensland (Australia), is a prime example of a basalt fractured-rock aquifer. Yet very little is known about the hydrochemistry of this groundwater system. Both analytical (major ions and stable isotopes) and multivariate (hierarchical cluster analysis, principal component analysis and factor analysis) analyses were used in this study to investigate the factors that interact within this aquifer system, in order to determine groundwater hydrogeochemistry. A new approach was applied to the data by classifying hydrographs by water type to clearly identify differing aquifer zones. Three distinct groundwater chemistry types were identified, and they were differentiated by variations in depth. Shallow bores were dominated by Na–Cl waters, deep bores were dominated by Na–HCO3 and Ca–HCO3 waters, and the two deepest bores were dominated by mixed water types. The evaluation of hydrogeochemical data has determined that both mineral weathering processes and groundwater/surface-water interaction had a strong influence on the hydrogeochemistry. Seasonal effects were minimal in the study area based on physicochemical parameters and ion chemistry. However, stable isotopic data show temporal trends. Increased rainfall events during the wet season produced a depletion in δ18O and increased d-excess values. The opposite is found during the dry season as a result of higher evaporation rates that are not hindered by intense rainfall events.

Purpose The purpose of this paper is to explore the social climate of therapeutic wings and mainstream wings within one prison, to identify positive areas of social climate that can be built upon and areas for improvement. Design/methodology/approach In total, 1,054 social climate questionnaires (the Essen Climate Evaluation Schema – EssenCES) were sent to prisoner-facing staff and all prisoners within an English Category B prison holding indeterminate sentenced prisoners. Perceptions of social climate on therapeutic wings and mainstream wings and perceptions of social climate between staff and prisoners were compared. Findings The results showed that the therapeutic wings felt safer, there were better staff-prisoner relationships and there was better peer support among prisoners than people on the mainstream wings. Also, prisoners felt safer than staff, staff rated the overall social climate as more positive than prisoners and staff felt that they supported prisoners, but prisoners did not feel the same. Research limitations/implications The main limitation is that the EssenCES measure does not explain the participants’ ratings of the social climate. Practical implications There is a need to transfer the principles and values of therapeutic wings to mainstream wings. In addition, there is significant room for improvement in the social climate of this prison. Originality/value This is the first study to compare the social climate of therapeutic and mainstream wings within one single prison. The research has a valuable contribution to the development of positive social climates conducive to better clinical outcomes.

The quantification of percolation processes and deep drainage rates in cracking clays is challenging due to the existence of multiple flow pathways, including desiccation crack networks, and the effect of variability in antecedent soil moisture and rain event properties. While most previous research on this topic focuses on long‐term average rates, this study focusses on inter‐event dynamics. The study uses data from soil moisture sensors distributed vertically down 4 m profiles of Vertosol and Chromosol soils across 13 sites over an area of approximately 20 km2. The objectives were to estimate the temporal and spatial variability of deep drainage rates and to investigate the effect of antecedent soil moisture conditions and rain event properties on deep drainage rates and percolation dynamics. 35 deep drainage events over a 40‐month period contributed 78 % of the total deep drainage of 254 mm at 4 m depth. Average deep drainage estimates were about 15 % (ranging from 0 – 80 % between sites) of total rainfall and irrigation in the Vertosol and 8% (0 – 24 %) in the Chromosol. The event water travel times at 4 m depth were 0.25 – 38 hr and 14 – 39 hr in the Vertosol and Chromosol respectively. The event deep drainage rates averaged across sites were associated with event rainfall volumes (linear regression R2 = 0.40), with the effect of antecedent conditions evident only when looking at inter‐site differences. The percolation response time was strongly associated with higher rainfall intensities (R2 = 0.33) with no evidence from the linear regression of an antecedent moisture effect.

Groundwater management in irrigation areas requires a comprehensive understanding of the interactions between agricultural management practices and the underlying groundwater resource. Unsaturated zone modelling can be used to predict rates of water and solute movement through the soil profile. By incorporating expert knowledge and measured data, it is possible to investigate the relative influence of management vs environmental factors on water and solute movement. The Agricultural Production Systems sIMulator (APSIM) has been applied to simulate the impacts of both environmental factors and agricultural management factors on deep drainage and nitrate leaching in the Lower Burdekin, North Queensland, Australia. Based on the results of this modelling, predicted annual average deep drainage rates were found to be controlled primarily by soil properties, irrigation scheduling, and, to a lesser extent, annual rainfall. The key factors which were found to control nitrate leaching were: irrigation water quality, fertilizer application rates, soil type, crop management, and irrigation scheduling. However, increases in the concentrations of nitrate in irrigation water resulted in a 64-fold increase in predicted nitrate-leaching rates, compared with a 22-fold increase in predicted nitrate-leaching rates associated with increased fertilizer application rates. As significant quantities of nitrate are predicted to be leached below the root zone, the immediate priority should be to increase monitoring of groundwater quality with a focus on quantifying the transport of nutrients to sensitive receptors.

Opencast coal mining has a series of consequences on land resources and places enormous pressure on the ecological environment. Stripping, excavation, transportation and dumping have different effects on soil physical, chemical and biological properties. Moreover, the reconstructed landscape produces increased small-scale spatial heterogeneity of mined soils. Currently, growing concerns for the negative consequences of mining have highlighted the importance of reclamation in minesoil studies. This review has examined the mechanisms of coal mining and reclamation that affect soil properties (physical, chemical, biological) and described soil development in reclamation, with an emphasis on the reclaimed minesoil (RMS) properties of reclamation sites. The major conclusions of this review were: (i) The randomness of soil dumping increased the heterogeneity of minesoil properties, which in turn increased the complexity of reclamation practice. (ii) The negative or positive consequences of mining and reclamation processes on RMS need to be recognized by scientific observations such as soil property multi-index analysis and soil chronosequences, on which the minesoil reconstruction practice are based. (iii) Five phases of reclamation (i.e., geomorphic reshaping, soil reconstruction, hydrological stability, vegetation restoration, and landscape rebuilding) should be considered as a comprehensive system for the reconstruction of minesoils. (iv) The application of new technologies (e.g., micro-terrain reshaping and soil non-destructive detection) and new studies (e.g., systematic study, rebuilding animal habitat, and biodiversity research) to minesoil recovery practice would enhance the new concepts of land reclamation and ecological restoration in mining areas.

The transport of nitrogen (N) to groundwater and surface water in the form of nitrate (NO3-), as a by-product of the application of N-rich fertilisers, has been studied extensively. Yet, in the catchments adjacent to the Great Barrier Reef (GBR) in tropical north Queensland, Australia, NO3- transport in groundwater is not regularly monitored. An assessment of groundwater chemistry in the Liverpool Creek catchment of Queensland's wet-tropics region was conducted by regular sampling and analysis of groundwater over 12 months, through wet and dry seasons. A distinct spatial variability in groundwater chemistry was observed; groundwater aquifers with very low dissolved oxygen (DO) and NO3- consistently displayed relatively higher concentrations of sulphate (SO42-), sulphur (S2-) and ferrous iron (Fe2+) and low concentrations of dissolved organic carbon (DOC) (, Groundwater; nitrate; Sugarcane; Tropics, Sulphate; Denitrification; Soil Chemistry; Environmental Chemistry; Water Geochemistry; Contaminant Transport; Geochemistry, Environmental science.

Knowledge of recharge processes in groundwater resource areas is of great importance for developing sustainable water management plans. In an effort to enhance the understanding of recharge in a basalt aquifer, a national water balance soil moisture model was compared with the response in water tables in multiple private pumping bores across the Tamborine Mountain plateau located in South East Queensland, Australia. The water levels in the pumping bores were influenced by the everyday use of the bores, which are utilised for household supply, stock watering, garden watering and irrigation. In each bore, the pumping response was identified and filtered out before being compared to the soil moisture model results. The soil moisture model (AWRA-L Australian Water Resource Assessment Landscape) includes results of surface runoff, soil moisture, evapotranspiration and deep drainage, to a depth of 6 m. The simulated soil moisture levels in the rootzone (rootzone defined as depth between 0 - 1 m), showed a similar hydrographic response following rain events to that observed in water levels in the aquifer. The response in the aquifer compared to the soil moisture showed some of the deeper bores had a lag effect and furthermore, the response also showed dependency on the soil moisture level (%) and on the size/duration of the rain event. It was observed that the simulated deep drainage (recharge) did not correlate to the observed changes in water tables. The soil moisture model simulated a nearly constant deep drainage (recharge) of 0.05±0.01mm a day, whereas the bores showed large increases in water table in response to rainfall events. Previous studies in the area based on the chloride mass balance approach have estimated that the annual deep drainage volume was an average of 30% of annual rainfall, while the soil moisture model approach has simulated an annual deep drainage volume of 1.2 – 1.7% of the total annual rainfall. While these results show that there are shortcomings related to applying the soil moisture model to estimate aquifer recharge, these results are an important initial finding regarding the estimation of recharge in the study area and can be used in water balance calculations for water management purposes. With further research into the observed relationships and parameterisation of these relationships, the soil moisture model could be updated to better represent recharge within this, and similar, study areas.

In 2007, Langkawi Island in Malaysia was awarded UNESCO Global Geopark status, partly due to its diverse geological setting which includes tropical karst limestones. Whilst extensive studies of the geological setting at Langkawi Island have been carried out, the hydrogeochemistry and hydrogeology of the karst systems in this region have received little attention.At the Penarak Nature Centre on Langkawi Island, the early stages of construction for an ecotourism resort within a limestone forest are taking place. At this site, water sampling and analyses were carried out, with a team of undergraduate science students, to characterise the baseline surface water and groundwater chemistry. Samples were collected from 10 locations at the limestone forest site. As no groundwater monitoring bores were available at the site, samples were instead collected from 4 identified groundwater seepage sites, in addition to 5 surface water sites and 1 seawater site. Field measurements of pH, EC, redox potential, dissolved oxygen and temperature were obtained. Samples from each site were also analysed for δ18O, δ2H and major ions.Through a combination of geochemical plots and multivariate data analysis (Principal Components Analysis and Cluster Analysis), relationships between the water composition from different sites were identified. The water type for all of the groundwater seepage and surface water sites was Ca-HCO3, indicating a high degree of groundwater-surface water interaction and rock dissolution. The multivariate data analysis results also provided an indication that groundwater sites located less than 300 meters apart may be flowing through separate karst conduits. One of the groundwater seepage sites, located close to construction, was identified as having higher concentrations of magnesium, calcium and sodium when compared with all of the other groundwater seepage and surface water sites. As there is little known about the karst hydrogeology and hydrochemistry on Langkawi Island, it is not clear whether the chemical differences identified at this construction site are occurring due to local heterogeneities in the karst system or due to anthropogenic impacts.This study has been able to provide some baseline geochemical data and preliminary insights into groundwater and surface water interactions in a limestone forest at Langkawi Island. Recommendations for further research include a program of geophysical/hydrogeological mapping of the karst system and the establishment of a water monitoring network within the limestone forest.

Poor soil physical conditions associated with low hydraulic conductivity and infiltration can limit salt leaching and reclamation; hence, land revegetation. Soil physical amendments such as wood chips and fine sand may be used to remediate the soil physical conditions and improve salt leaching, thus assisting with revegetation. To evaluate the success of soil amendments for the reclamation and revegetation of a saline-sodic soil under a typical climatic condition of a semi-arid environment, a water and solute transport model (HYDRUS-1D) was used. Synthetic climatic scenarios were generated using LARS-WG. Soil profiles (1 m depth) amended separately with 20% wood chips and 40% fine sand at the surface (0–10 cm) were defined for the simulation. A non-amended soil profile, which had physical properties of a disturbed soil, was used as a control. Salt leaching was more successful in the non-amended soil profile compared with the amended soil profiles. The likelihood and the success of Atriplex halimus L. seed germination were also higher in the non-amended soil (67.7%) compared with wood chips (13.98%) and fine sand (6.7%) amended soils. This study indicates that the addition of 20% wood chips and 40% fine sand to the depth of 10 cm of a saline-sodic soil may not be an effective approach for reclamation and revegetation under the semi-arid climatic conditions. This study suggests that a reduction in soil bulk density is sufficient to provide suitable conditions for successful land reclamation and revegetation in the investigated climatic conditions.

Purpose: The use of heavy machinery in mining areas increases during mining and dumping of waste soils, causing severe soil compaction and potentially affecting soil recovery. This study aimed to capture the features of complex compacted soil pore structure using computed tomography (CT) and to quantify soil pore distribution properties based on Minkowski theory. Materials and methods: A total of 45 cylindrical soil columns were extracted from different soil layer at 5 sampling sites that differed in compaction level in Pingshuo opencast coal mine in Shanxi Province of China. The penetration resistance at these sites ranged from 27.3 to 1023.1 kPa. Three-dimensional reconstruction software VGStudio was used to obtain the morphological characteristics (pore volume density, VD; surface density, SD; mean curvature density, MCD; and Euler number, EN) of soil pores after processing the X-ray scanned image. Results and discussion: Compaction generally reduced VD, SD, and MCD, which ranged from 0.10 to 0.20, 2.23 to 2.80 mm 2 mm −3 , and 10.75 to 15.64 mm mm −3 respectively in undisturbed site P0, whereas, they ranged from 0.02 to 0.07, 0.13 to 0.60 mm 2 mm −3 , and 1.61 to 4.27 mm mm −3 respectively in highly compacted site P4. The three index exhibited the similar trend, and decreased with the increase of compaction level. Soil compaction had positive effects on EN, which was low at the depth of 20- to 40-cm layers but showed an increasing trend with increasing soil compaction level. The value of EN varied from 28,878 to 129,861 in P0, whereas it varied from 1,169,967 to 2,281,998 in P4. Conclusions: All of macroporosity, mesoporosity, and microporosity were significantly affected by heavy machinery compaction, among which macroporosity exhibited the maximum decrease in P4 compared to that in P0 (P0 ranged from 14.2 to 26.4% and P4 ranged from 0.2 to 1.4%). The soil compaction in mining area significantly affected soil properties, thus artificial methods such as fertilizer application and deep tillage were needed.

The usage of Photosystem II (PS II)–inhibiting herbicides, identified as a risk to ecosystem health and resilience, has been reduced in agricultural activities adjacent to the Great Barrier Reef, Australia over the past 10 years. Two PS II herbicides (diuron and hexazinone) and three metabolites (desethyl atrazine, hydroxyatrazine and DCPMU) were recently detected at low concentrations in the regional aquifer of the South Johnstone River sub-basin, in the Wet Tropics, Australia. This study presents results from monitoring 12 PS II herbicides in soil profile, porewater sampled through the vadose zone monitoring system, and groundwater from bores. Among the 12 PS II herbicides, only hexazinone and metribuzin were applied relatively recently, in November 2014. Hexazinone exhibited substantial transport through the vadose zone, with decreasing concentration with depth, and eventually disappeared over-time. Metribuzin was not detected in the groundwater, in soil profile or through the vadose zone. Diuron was detected in the soil profile, through the vadose zone and in bores at the site. Its two metabolites—1-(3,4-dichlorophenyl)-3-methylurea (DCPMU) and 3,4-dichloroaniline—were detected in the deepest port at 4 m, indicating the transformation of diuron into these metabolites and potential leaching. The other nine PS II herbicides were not detected in the soil profile, through the vadose zone or in bores at the site. Some of the PS II herbicides were detected in the soil profile and beyond the root zone, depending on their application record and persistence in the environment. Therefore, the data shows that the herbicides are long lived at low concentrations. However, herbicide concentrations in subsoil, vadose zone and groundwater are low (less than environmental guideline values) and are detected at much lower concentrations than in surface runoff.

Highlights - A slower water movement is associated with a greater salt leaching efficiency. - A greater rate of cation exchange can increase salt leaching. - Addition of bentonite can improve the reduction of soil salinity. Abstract Saline-sodic soils may be reclaimed through the addition of amendments to alter the soil pore system and hydraulic functions, therefore allowing salts to be leached from the soil. For the purpose of investigating the suitability of specific amendments for improving leaching and reclamation, soil percolation column studies were conducted to assess the influence of amendments on cation exchange, the potential for the release of cations and changes in hydraulic conductivity of the soil. A fine textured saline-sodic soil amended separately with 20% wood chips (wt/wt), 40% fine sand (wt/wt) and 2.5% bentonite (wt/wt) was used for this study as well as a non-amended soil as a control. The impact of amendments was evaluated by continuous leaching of the soil substrates with deionized water until the hydraulic conductivity and leachate chemistry stabilised. The bentonite amended soil had a greater increase (15.9 cmolc kg−1) in exchangeable Ca2+ and a higher reduction in exchangeable Na+ (12.29 cmolc kg−1) after the final leaching due to a greater rate of cation exchange for this soil substrate. The bentonite amended soil also had a greater reduction (92%) in Na+ content compared with the other soil substrates. The hydraulic conductivity of all soil substrates improved during leaching although the hydraulic conductivity of bentonite amended soil reduced after three pore volumes of leaching. This study suggests that a slower water movement (an increased percolation time) and a greater rate of cation exchange were associated with the greater leaching efficiency. Therefore, addition of bentonite improves and accelerates the reduction of salinity and sodicity.

Woodchip bioreactors have the capability to promote the reduction of reactive nitrogen in the nitrate (NO3−) form to dinitrogen (N2), a harmless gas in the atmosphere. Nevertheless, during the reaction the potent greenhouse gas nitrous oxide (N2O) is produced and can be released if denitrification is not complete. The aim of this experiment was to quantify the effect of a soil cap, the concentration of NO3− inflow and drying-rewetting cycles (DRW) on N2O emissions from bench top bioreactors (BTBs, 36.2 × 24.2 × 16.8 cm). The soil cap effect was quantified by comparing the performance of two treatments (n = 3): soil cap (CAP) and soil cap free (UNCAP). The NO3− inflow was simulated by feeding the BTBs with two NO3− concentrations (10 and 5 mg N L−1), and DRW were simulated by saturating and draining the BTBs. Nitrous oxide was quantified in the water samples as well as measured from the surface of the BTBs. The soil cap proved effective at decreasing surface N2O emissions with a reduction of total N2O emissions (calculated as the sum of dissolved N2O and surface N2O emissions) ranging from 30.4 to 42.9%. The NO3− inflow affected dissolved N2O and surface N2O emissions with higher values (average of 3.41 and 0.36 mg m−2 d−1, respectively for CAP, and average of 2.92 and 2.52 mg m−2 d−1, respectively for UNCAP) measured at high NO3− inflow. Drying-rewetting cycles influenced dissolved N2O and surface N2O emissions, with values following rewetting that accounted for more than 56% of the total N2O emissions for both treatments. This study confirmed that soil caps are effective at mitigating N2O emissions and contributed to a better understanding of N2O dynamics induced by two different NO3− inflow concentrations and DRW.

Denitrification walls are a low-cost technology with the capability to reduce nitrogen (N) loading in shallow groundwater beneath agricultural systems. The aims of this study were to quantify the effect of different carbon (C) substrates on nitrate removal rate (NRR) and greenhouse gas (GHG) production in two soil-capped denitrification walls (volume ≈ 27 m3) under subtropical climate conditions. The relative performance of softwood and hardwood woodchips to promote denitrification was tested over a 2-year program of weekly monitoring, during which water samples were collected for nitrate (NO3−) and dissolved GHG analysis. Both the softwood and the hardwood wall had similar average NRR (2.0 and 1.6 g N m−3 d−1, respectively) but were NO3− limited, and acted as a sink for nitrous oxide (N2O) produced in the walls and dissolved in the aquifer. Both walls produced carbon dioxide (CO2) and methane (CH4), with the hardwood producing respectively 3-fold and 2.5-fold higher fluxes compared to the softwood. Calculation of the Global Warming Potential (GWP) permitted a comparison of the GHG emissions within the walls in terms of CO2 equivalents (CO2-eq). Both the walls emitted CO2-eq lower than natural environments, with the softwood producing null emissions and the hardwood emitting 65-fold higher than softwood. The results of the present study suggest that woodchip bioreactors may be used to reduce nutrient loading from agricultural areas into surrounding aquatic environments as well as to decrease GHG emissions under subtropical climates, with softwood being a preferable substrate.

Heavy machinery compaction in mining area is widespread, and seriously jeopardizes soil restoration. Characterization of soil macropores with three-dimensional methods is essential for understanding the reclaimed minesoil (RMS) development. The aim of this study was to demonstrate the application of X-ray computed tomographic (CT) scanning for analyzing soil macropore structure and to explore how soil compaction affects soil macropore properties. To achieve this, soil samples collected from Pingshuo opencast coalmine were tested through a laboratory scheme, which was conducted to simulate the real soil pore situation under increasing soil bulk density treatments of 1.3, 1.4, 1.5, 1.6, 1.7, and 1.8 g cm−3 (T1.3-T1.8). Three-dimensional (3D) macropore networks were observed via CT, and macroporosity, macropore number, area, volume and its connectivity were characterized. Soil compaction had a major impact on soil macropore characteristics. The macropores of the 1.3 g cm-3 treatment were well connected, whereas those of the 1.8 g cm-3 treatment were poorly connected and isolated from each other. Macropore number and macroporosity decreased significantly as the soil compaction increased. Moreover, a 3D visualization of soil pore connectivity results suggested that the macropore connectivity markedly decreased with increasing compaction level, with average Euler number increasing from 0.677 in the 1.3 g cm-3 treatment to 0.999 in the 1.8 g cm-3 treatment. Soil bulk density was negatively correlated with macropore throat number and thickness, indicating that the soil compaction causes a loss of pore connectivity. Despite using a coarse resolution, the combination of laboratory simulation tests and 3D visualization of soil macropores provides valuable data for identifying the differences in soil pore structure among compacted RMSs and monitoring the persistent effects of soil compaction caused by heavy machinery in the mining area. Furthermore, we recommend a new method combining 3D visualization techniques and hydraulic analysis in the study of compacted soils, and the establishment of soil restoration measurements to avoid further compaction in mining areas.

In this paper we discuss the use of a series of column experiments to improve understanding of the effect irrigation water chemistry (saline solutions) has on measurements of saturated hydraulic conductivity (Ksat) of a sodic clay soil. We highlight in particular the use of extended leaching periods to determine whether the duration of leaching affects the results. In the experiments, mixed cation solutions of two different salinity levels, 50 meq/L and 100 meq/L, were applied under constant head to columns of a repacked sodic clay soil using three replicates for each treatment. The maximum Ksat measured during leaching with the 100 meq/L solution was approximately double the maximum Ksat measured during leaching with the 50 meq/L solution. Measured flow rates were found to increase rapidly after flow commenced then decrease gradually until flow rates became stable. The final, stable flow rate was roughly 80% less than the maximum flow rate measured. Reasons for these changes in saturated hydraulic conductivity are discussed. The key finding from these experiments is that long term leaching, involving significantly more pore volumes than is commonly reported in the literature, is required to obtain a ‘stable’ Ksat. We recommend that further studies be carried out to (1) determine whether similar behaviour in Ksat occurs in a wide range of sodic clay soils and (2) to help build a better understanding of the causes and implications of the observed behaviour in Ksat.

Purpose – The purpose of this paper is to explore the perceptions, beliefs and abilities that support adult male prisoners in overcoming suicidality. Design/methodology/approach – Semi-structured interviews were conducted with eight male life sentenced prisoners in a Category B prison. Thematic analysis was used to analyse the data and interpret how prisoners have overcome suicidality. Findings – Five overarching themes were identified; sense of self, presence of meaning, connectedness, shift of perspective and re-establishing control. The themes were closely interconnected and revealed novel insights into the variables that supported prisoners to overcome suicidality. Research limitations/implications – The themes were drawn from a specific prisoner population, which may not be representative of the wider prison population. Additionally, the sole focus on suicidality may be an oversimplification of self-destructive behaviours and could have affected the factors identified. Practical implications – The results highlight the need to refine suicide prevention strategies in prisons; in the assessment of suicide risk, the improvement of supportive regimes and the development of psychological interventions. Originality/value – This research is the first to qualitatively examine the factors involved in overcoming suicide in adult male prisoners. The research is of value to researchers and practitioners alike, as it extends previous research in prison populations and suggests avenues for the development of suicide prevention strategies.

Amelioration of sodic soils is commonly achieved by applying gypsum, which increases soil hydraulic conductivity by altering soil chemistry. The magnitude of hydraulic conductivity increases expected in response to gypsum applications depends on soil properties including clay content, clay mineralogy, and bulk density.The soil analyzed in this study was a kaolinite rich sodic clay soil from an irrigated area of the Lower Burdekin coastal floodplain in tropical North Queensland, Australia. The impact of gypsum amelioration was investigated by continuously leaching soil columns with a saturated gypsum solution, until the hydraulic conductivity and leachate chemistry stabilized. Extended leaching enabled the full impacts of electrolyte effects and cation exchange to be determined.For the columns packed to 1.4 g/cm, exchangeable sodium concentrations were reduced from 5.0 ± 0.5 mEq/100 g to 0.41 ± 0.06 mEq/100 g, exchangeable magnesium concentrations were reduced from 13.9 ± 0.3 mEq/100 g to 4.3 ± 2.12 mEq/100 g, and hydraulic conductivity increased to 0.15 ± 0.04 cm/d. For the columns packed to 1.3 g/cm, exchangeable sodium concentrations were reduced from 5.0 ± 0.5 mEq/100 g to 0.51 ± 0.03 mEq/100 g, exchangeable magnesium concentrations were reduced from 13.9 ± 0.3 mEq/100 g to 0.55 ± 0.36 mEq/100 g, and hydraulic conductivity increased to 0.96 ± 0.53 cm/d.The results of this study highlight that both sodium and magnesium need to be taken into account when determining the suitability of water quality for irrigation of sodic soils and that soil bulk density plays a major role in controlling the extent of reclamation that can be achieved using gypsum applications.

Poor soil physical conditions such as low hydraulic conductivity can limit salt depletion from surface soil. Altering the pore system by addition of organic and inorganic amendments may improve salt leaching as a reclamation strategy. Column studies were conducted to investigate salt leaching in amended and non-amended soil profiles. A one-dimensional water and solute transport model (HYDRUS-1D) was also assessed for its applicability to simulate salt leaching for amendment strategy. Columns of length 300mm were filled with saline-sodic soil at the lower end (100–300mm) and then covered with soil amended with 40% (wt/wt) fine sand and 20% (wt/wt) wood chips, separately. A control column was filled with saline-sodic soil only. One rainfall scenario typical for a location in south-west Queensland (Australia) was applied to the columns. Water potentials were monitored using tensiometers installed at three depths: 35, 120 and 250mm. The concentrations of individual cations (Na+, Ca2+, Mg2+ and K+), electrical conductivity and sodium adsorption ratio of the soil solutions were also monitored for the investigated depths. A reduction in surface salinity (up to 28.5%) was observed in the amended soil profiles. This study indicated that the addition of wood chips to surface soil improved salt leaching under the tested conditions. The simulation successfully predicted both hydrology and chemistry of the columns. This study also concluded that HYDRUS-1D is a powerful tool to simulate salt leaching in the amended soil profiles, and can be applied to predict the success of amendment strategy under natural climatic conditions.

There is significant interest in estimating volumes of water extracted during production as the CSG industry develops in the Surat and Bowen basins in Queensland, Australia. Klohn Crippen Berger Ltd (KCB) was commissioned by the Queensland Department of Natural Resources and Mines (DNRM) to develop a tool to estimate where, when, and how much CSG water will be produced in these areas under various industry expansion scenarios. The tool, which is now being maintained and further developed to interface with GIS software by the Centre for Water in the Minerals Industry (CWiMI), was built to balance numerical complexity against relative flexibility and simulation speed. This was achieved by an approach that differs from conventional reservoir engineering models, including: the use of non-equilibrium groundwater flow equations (the Theis equation) in conjunction with semi-empirical type-curve based methods; calculation of well interference effects and corresponding spatial scaling effects in a relatively large-scale spatially discretised model; and, modification of flows predicted using the Theis equation to reflect the dual-phase nature of CSG extraction, and the unique hydrogeological setting of the eastern margin of the Surat Basin. The tool was verified against equivalent Theis equation calculations and type curves provided by CSG proponents. The tool was demonstrated to adequately represent the unique physical mechanisms of CSG extraction, and produce robust estimates of CSG water production at a regional scale, while not relying on excessively complex numerical models or excessive data input requirements.

Management of sodic soils under irrigation often requires application of chemical ameliorants to improve permeability combined with leaching of excess salts. Modeling irrigation, soil treatments, and leaching in these sodic soils requires a model that can adequately represent the physical and chemical changes in the soil associated with the amelioration process. While there are a number of models that simulate reactive solute transport, UNSATCHEM and HYDRUS-1D are currently the only models that also include an ability to simulate the impacts of soil chemistry on hydraulic conductivity. Previous researchers have successfully applied these models to simulate amelioration experiments on a sodic loam soil. To further gauge their applicability, we extended the previous work by comparing HYDRUS simulations of sodic soil amelioration with the results from recently published laboratory experiments on a more reactive, repacked sodic clay soil. The general trends observed in the laboratory experiments were able to be simulated using HYDRUS. Differences between measured and simulated results were attributed to the limited flexibility of the function that represents chemistry-dependent hydraulic conductivity in HYDRUS. While improvements in the function could be made, the present work indicates that HYDRUS-UNSATCHEM captures the key changes in soil hydraulic properties that occur during sodic clay soil amelioration and thus extends the findings of previous researchers studying sodic loams.