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Exposure of bare soil for long periods and onsite compaction create soil and water problems in asparagus production. This project aims to develop a cost effective and practical runoff and soil erosion management system. Two field trials (Phase 1 running from April - July 2012 and Phase 2 running from May - November 2013) tested different combinations of shallow soil disturbance (SSD) and mulch (straw and compost) application for soil erosion control. Cranfield University’s soil bin was used to test the effect of different tine configurations on soil disturbance. The results of this research corroborated observations that asparagus production can result in levels of unsustainable soil loss that will contribute to the degradation of the existing soil resource. The field trials demonstrated that a straw mulch applied at 6 t ha- 1 significantly improved key performance indicators (KPIs, i.e. runoff initiation, volume and rate; total soil loss; sediment concentration; total oxides of nitrogen; orthophosphate-P; and sediment-bound P) as compared with the Non-SSD Control. In general, SSD (irrespective of tine configuration) was ineffective at improving key performance indicators as compared with the Non-SSD Control. In the soil bin work, different tine configurations generated varying degrees and extent of SSD, with the modified para-plough giving the greatest soil disturbance for the least draught force. However, the differences in SSD observed in the soil bin had no effect on the KPI’s tested in the Phase 2 field trial. The effective treatments observed in the field trials only yielded cost savings to the farmer/grower when a high level of soil loss occurred. This research highlights the need to develop erosion control measures in asparagus fields, with wider implications to other row crops. However caution is needed, given the observed variation in effectiveness and reliability of in-field mitigation measures, especially during ‘extreme’ rainfall events.

Although blanket peat covers many major headwater areas in Britain, runoff production within these upland catchments is poorly understood. This thesis examines runoff production mechanisms within the blanket peat catchments of the Moor House National Nature Reserve, North Pennines, UK. Catchments ranging from 11.4 km^ down to the hillslope and plot-scale are examined. Runoff from the monitored catchments was flashy. Lag times are short and rainwater is efficiently transported via quickflow- generating mechanisms such that flood peaks are high and low flows poorly maintained. Hillslope and plot-scale runoff measurements show that the flashy catchment response is the result of the dominance of overland flow. Typically 80 % of runoff is produced as overland flow. This occurs both on bare and vegetated surfaces. Most of the remaining runoff is generated from the upper 10 cm of the peat, except where well-connected macropore and pipe networks transfer flow through the lower layers. Below 10 cm depth the blanket peat matrix fails to contribute any significant runoff Thus most groundwater-based models of peat hydrological process are not readily applicable to these catchments. Suggestions that infiltration-excess overland flow may be largely responsible for the flashy regime of these upland catchments are not substantiated by the blanket peat infiltration data presented in this thesis. Monitoring of hillslope runoff mechanisms combined with rainfall simulation (at realistic intensities of 3-12 mm hr(^-1)) and tension- infiltrometer experiments shows that saturation-excess mechanisms dominate the response. Infiltration is relatively rapid in the upper peat layers until they become saturated and overland flow begins. High water tables result in rapid saturation of the peat mass such that even at low rainfall intensity runoff production is just as efficient as during high intensity events. While macropores have largely been ignored in blanket peat, results presented suggest that up to 30 % of runoff may be generated through them. Occasionally these macropore networks develop through the deeper peat such that runoff bypasses the matrix and runs off at depth from small outlets and larger pipe networks. Seasonal variations in runoff- generating processes can be exacerbated by drought which causes structural changes to the near-surface of the peat. This was found to result in enhanced infiltration and macropore flow which may encourage pipe network development. Flow has been monitored simultaneously from several natural pipes in a 0.4 km(^2) headwater catchment of the Tees. This catchment provides one of the few examples of pipeflow monitoring outside the shallow peaty-podzols of mid-Wales. Natural pipes are found throughout the soil profile and can be at depths of up to three metres. Ground penetrating radar was useful in identifying deep subsurface piping and suggestions are made for improvements to the application. The pipe networks were found to be complex and results demonstrate that outlet location and size may bear little relation to the form and depth of the pipe a short distance upslope. Pipes generally contribute less than 10 % to catchment runoff but on the rising and falling hydrograph limbs can contribute over 30 % to streamflow. Pipeflow lag times are short suggesting that both the shallow and deep pipes may be well connected to the surface. Thus while matrix runoff contributions at depth within the peat may be low, macropore flow mechanisms can be significant.

Permeable pavement structures (PPSs) are one of the significant LID systems that have potential positive effect on the ecosystem. Yet, the performance of permeable pavements is still questionable. Further studies on the hydrological performance of the system need to be addressed for better design criteria and maintenance during the operation. The infiltration through the pavement is a crucial parameter that projects the system performance. Several factors affect its deterioration. The entrapment of suspended materials associated with the infiltrated stormwater through the system is one of the major factors that affect its performance. Factors that promote the entrapment of particles were discussed thoroughly through the literature and are explained in this study. Many previous studies were focused on performing experimental work and developing empirical models to study the hydraulic performance of the system. Yet, prediction models on the infiltration deterioration need to be addressed and theoretical analysis needs to be performed in order to determine the empirical coefficients with defined parameters that were introduced in the previous literature. Furthermore, the sensitivity of the pore and particle size distribution and mass loading rate of the suspended materials on the infiltration rate need to be addressed. The study focuses on investigating performance of PPSs with examining the variation effect of pore and particle size distribution on it. A prediction model was made and simulated using Matlab software, in which pore and particle size means and standard deviations are taken as inputs. Further, the variation in these parameters on infiltration is examined. Critical levels, that infiltration decline would reach, were defined based on the introduced mechanisms from the previous literature. Based on the variation of pore and particle size means and standard deviations, these critical levels were studied through the analysis of the obtained results from the simulated model. / Graduate / 2019-12-10

Urban stormwater runoff is recognised as a substantial source of heavy metal contamination, which adversely impacts on water quality of regional receiving waterways. Conventional treatment of urban runoff mostly involves a filtration system using sand to retain particulate matters. Sand provides limited sorption of dissolved metals and the inclusion of commercial sorbents to these treatment systems is not cost effective due to the concentration of dissolved metals in the runoff. Recycled organic materials are by-products or waste from industrial or agricultural operations, and could be alternative low cost sorbents for stormwater treatment systems. The use of recycled sorbents also provides added value to the waste materials and reduces landfill disposal. The research explores the application of compost, zeolite, ash, and recyclable waste in urban runoff treatment, especially for dissolved metal removal. The research combines the two aspects of experimental studies and management analysis to develop a holistic approach to heavy metal control in urban stormwater systems. Experimental results of batch sorption test show that compost is suitable for removing dissolve copper in stormwater treatment. The comparison of the different mixing ratios between compost and glass beads in column test evaluates the optimum mixing sorbent and performance over a long period for copper removal. Substance Flow Analysis (SFA) of copper has been performed in the Upper Parramatta River Catchment, Sydney to identify the sources of copper associated with runoff, effect of using waste material such as compost in urban stormwater treatment and the copper load in urban stormwater runoff. This case study shows the relationship between copper input, copper stock, sorbent type and urban stormwater quality control in the system boundary of the catchment. Different scenarios of source control are evaluated to control copper load from the different sources. Source control focusing on roads and vehicles is the most effective copper control strategy. The combination of source control and stormwater treatment reduces copper in stormwater and receiving water. The thesis applies the analysis from SFA and experimental results to derive both a regional system-wide solution with source control, and an improved design of stormwater treatment for heavy metal removal using recycled organics.

<p>Postoperativ smärta upplevs av många patienter trots att det finns effektiv smärtlindring tillgänglig. Infiltrationsanestesi är en metod då lokalanestetika injiceras i operationsområdet och därmed blockerar överföringen av smärtimpulserna till centrala nervsystemet. Syftet var att undersöka om infiltrationsanestesi vid bukkirurgi minskar den postoperativa smärtan. 16 randomiserade-dubbelblind studier analyserades och gav information om läkemedlets betydelse, administreringstillfället och det kirurgiska bukingreppets betydelse. 13 av 16 studier visade på en reducering av den postoperativa smärtan hos patienterna med variation från den första postoperativa timman upp till 10 dagar. Metoden att infiltrera lokalanestetika en och en halv timma före operationen med fortsättning under, i slutet och sex timmar efter den första infiltrationen gavs visade på längst uppmätt postoperativ smärtlindring. Kunskaper om anestesiformer och smärtbedömning krävs av sjuksköterskan för att i god tid möta upp med ytterligare smärtlindring. För att kunna ge förslag på evidensbaserad sjukvård och därmed minska patienternas lidande krävs noggrannare analys av variationerna i metoderna och ett ökat samarbete mellan olika yrkeskategorier.</p>

Porous tin oxide nanotubes were obtained by vacuum infiltration of tin oxide nanoparticles into porous aluminum oxide membranes, followed by calcination. The porous tin oxide nanotube arrays so prepared were characterized by FE-SEM, TEM, HRTEM, and XRD. The nanotubes are open-ended, highly ordered with uniform cross-sections, diameters and wall thickness. The tin oxide nanotubes were evaluated as a substitute anode material for the lithium ion batteries. The tin oxide nanotube anode could be charged and discharged repeatedly, retaining a specific capacity of 525 mAh/g after 80 cycles. This capacity is significantly higher than the theoretical capacity of commercial graphite anode (372 mAh/g) and the cyclability is outstanding for a tin based electrode. The cyclability and capacities of the tin oxide nanotubes were also higher than their building blocks of solid tin oxide nanoparticles. A few factors accounting for the good cycling performance and high capacity of tin oxide nanotubes are suggested. / Singapore-MIT Alliance (SMA)

The intra-basin variability of snowmelt and meltwater runoff hydrology in an 8 km2 subarctic alpine tundra catchment was examined for the 2003 melt period. The catchment, Granger Creek, is within the Wolf Creek Research Basin, Yukon which is typical of mountain subarctic landscapes in north-western Canada. The study catchment was segmented into nine internally uniform zones termed Landscape Units (LUs) based on their similar hydrological, physiographic, vegetation and soil properties. Snow accumulation exhibited significant variability among the LUs, with greatest snow water equivalent in areas of tall shrub vegetation. Melt began first on southerly exposures and at lower elevations, yet average melt rates for the study period varied little among LUs with the exception of those with strong aspects. In LUs with capping organic soils, meltwater first infiltrated this surface horizon, satisfying its storage capacity and then percolated into the frozen mineral substrate. Infiltration and percolation into frozen mineral soils was restricted where melt occurred rapidly and organic soils were thin; in this case meltwater delivery rates exceeded the frozen mineral soil infiltration rate, resulting in high runoff rates. In contrast, where there were slower meltrates and thick organic soils, infiltration was unlimited and runoff was suppressed. The snow water equivalent had a large impact on runoff generation as soil storage capacity was quickly surpassed in areas of deep snow, diverting the bulk of meltwater laterally to the drainage network. A spatially distributed water balance indicated that snowmelt freshet was primarily controlled by areas with tall shrub vegetation that accumulate large quantities of snow and by alpine areas with no capping organic soils. The intra-basin water balance variability has important implications for modeling freshet in hydrological models.

The intra-basin variability of snowmelt and meltwater runoff hydrology in an 8 km2 subarctic alpine tundra catchment was examined for the 2003 melt period. The catchment, Granger Creek, is within the Wolf Creek Research Basin, Yukon which is typical of mountain subarctic landscapes in north-western Canada. The study catchment was segmented into nine internally uniform zones termed Landscape Units (LUs) based on their similar hydrological, physiographic, vegetation and soil properties. Snow accumulation exhibited significant variability among the LUs, with greatest snow water equivalent in areas of tall shrub vegetation. Melt began first on southerly exposures and at lower elevations, yet average melt rates for the study period varied little among LUs with the exception of those with strong aspects. In LUs with capping organic soils, meltwater first infiltrated this surface horizon, satisfying its storage capacity and then percolated into the frozen mineral substrate. Infiltration and percolation into frozen mineral soils was restricted where melt occurred rapidly and organic soils were thin; in this case meltwater delivery rates exceeded the frozen mineral soil infiltration rate, resulting in high runoff rates. In contrast, where there were slower meltrates and thick organic soils, infiltration was unlimited and runoff was suppressed. The snow water equivalent had a large impact on runoff generation as soil storage capacity was quickly surpassed in areas of deep snow, diverting the bulk of meltwater laterally to the drainage network. A spatially distributed water balance indicated that snowmelt freshet was primarily controlled by areas with tall shrub vegetation that accumulate large quantities of snow and by alpine areas with no capping organic soils. The intra-basin water balance variability has important implications for modeling freshet in hydrological models.

Composted biological wastes contain vital plant nutrients that assist in plant growth as well as contain organic matter that promotes good soil conditions; both aid in rangeland restoration. Most importantly, it has the potential to restore water availability through increased infiltration and reduced runoff. In this thesis, local sources of composted dairy manure are utilized for application onto the degraded Fort Hood Western Training Grounds in central Texas in hopes to restore the rangeland for continued military training. Small scale rainfall simulations are applied two and eight months post-application of seven different agronomic rates of composted waste treatment (0, 5, 10, 15, 20, 25, and 30 y^3/acre) in order to determine changes in infiltration rates. July 2004 rainfall simulations, two months post application, indicate that composted wastes have not had sufficient time to incorporate into the soil matrix. Percent organic matter of the parent soil is the only significant variable of impact on maximum infiltration capacity. Composted waste treatments are concluded to have no effect on infiltration rates for any of the application rates in the summer rainfall simulations and are observed to exhibit very high variability in the amount of infiltration by a plot. January 2005 rainfall simulations, eight months post waste application, are observed to continue the trend of high variability across all treatment application rates. This variability is attributed to masking any potential effects from the treatment applications. Overall, this high natural variability disables the detection of potential effects of waste application treatments leading to the conclusion that composted waste applications do not affect infiltration on the Fort Hood Western Training Grounds. Runoff nutrient analysis observed nitrate-N to be well below Texas drinking water standards for all plots and phosphate to be above non-standardized values known to cause problematic algal growth. Natural rainfall events at intensities needed to generate runoff observed in this study are rare; therefore, nutrient pollution concern for local water bodies is low.