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<p> This study assessed the effect of an application of mycorrhizal fungi to stormwater filter media on urban bioswale soil and stormwater in an infiltration-based bioswale aged 20 years with established vegetation. The study tested the use of commercially available general purpose biotic soil blend PermaMatrix^&reg; BSP Foundation as a treatment to enhance Earthlite&trade; stormwater filter media amelioration of zinc, copper, and phosphorus in an ecologically engineered structure designed to collect and infiltrate urban stormwater runoff before it entered the nearby Willamette River.</p><p> These results show that the application of PermaMatrix^&reg; BSP Foundation biotic soil amendment to Earthlite&trade; stormwater filter media contributed to the reduction of extractable zinc in bioswale soil (-24% and -26%), as compared to the control, which received a treatment of Earthlite&trade; stormwater filter media only, and experienced an increase in extractable zinc levels (23% and 39%). The results presented also show evidence that after establishment mycorrhizal treatment demonstrated lowered levels of phosphorus in bioswale soil (-41%) and stormwater (-100%), in contrast to the control, which had increased phosphorus levels. The treatment contributed to reductions between 67% and 100% in every metric detected in stormwater after an establishment period of 17 weeks, while the bioswale with no mycorrhizal treatment had increases between 50% and 117%. Treatment also appeared to enhance the reduction of ammonium and nitrates, while contributing to a greater increase in soil pH. </p>

Understanding the link between tectonics and climate and their consequences in landscape evolution is a major current issue in Earth sciences. Bedrock rivers are an important component of the landscape because they transmit changes in tectonic and/or climatic conditions by setting bedrock incision rates to which the landscape must be adjusted. Nevertheless, there remain unresolved issues in relation to bedrock river processes and response to perturbation. The effects caused by propagation of a knickpoint triggered by a sudden drop in base-level remain to be fully clarified. Questions about rates of knickpoint recession, the control exerted by structure and lithology, the morphological response of rivers after knickpoint recession and whether bedrock incision rates are re-established after the passage of a knickpoint, as theory predicts, are all issues that need to be clarified. Moreover, the estimation of bedrock incision, which is key to understand transience in landscapes, has relied on the stream power model, mainly tested on large fluvial settings. Whether the stream power model is valid for small bedrock rivers is not well understood. Some of these questions are tackled in this research, by studying small bedrock river catchments. The case of a knickpoint propagation on a homogeneous resistant lithology (quartzite), triggered by an instantaneous base-level lowering ( 18 m in 13.6 ka), is evaluated here, as well as the effect of structure and the morphological response of rivers to base-level fall. Two approaches were followed: (1) stream profile analysis using slope-area and distance-slope plots and (2) the analysis of terrestrial cosmogenic nuclides to obtain erosion rates. The Isle of Jura, located in the west coast of Scotland, was selected as natural laboratory because bedrock rivers incise the landscape and rapid rock uplift resulting from glacio-isostatic rebound after the Last Glacial Maximum has left the Jura landscape in transience. The present research is organised in seven chapters. In chapter 1, the motivation for this research is presented. In chapter 2, a review of theory underpinning research on bedrock rivers, landscape evolution and knickpoint generation, is detailed. The relevant studies in the field are also reviewed. The physical setting of Jura is characterised in chapter 3, as well as the morphometry of catchments, stressing the effect of Quaternary glaciation on the landscape of Jura. Unpublished exposure ages and analysis of the resultant raised beaches (~35 m OD) of Jura’s west coast are used to demonstrate a sudden drop in base-level in Jura ~13.6 ka. Chapter 4 details how stream long profiles were extracted and how the slope-area (SA) and distance-slope (DS) analyses were undertaken. This chapter 4 shows that the Jura rivers have strong imprints related to glacial processes and base-level fall, making it difficult to use SA and DS models to estimate channel incision as has been done for large fluvial settings. Chapter 5 is explains how the base-level fall knickpoints were identified and it is shown that stream discharge is a first-order control on knickpoint propagation. Structure and lithology, on the other hand, are not first-order controls on knickpoint recession. Chapter 5 also evaluates the vertical distribution of knickpoints and morphological response of rivers after knickpoint migration, with the results indicating that stream power controls the vertical distribution of knickpoints and the morphological response of rivers to base-level fall. A threshold of ~5 km2, where rivers’ ability to modify their channel, resulting in a channel convex profile, is also identified. In chapter 6 the problem of bedrock incision and the role of sediment is tackled. Based on the sampling of sediment in fieldwork, it is demonstrated that the median fraction in the rivers of Jura is ≈45 mm and grain-size neither fines nor increases with stream discharge and channel slope, strongly indicating that detachment-limited conditions are likely to control bedrock incision. In the second part of chapter 6, the incision rates upstream and downstream of the base-level fall knickpoint are obtained to test whether incision rates are re-established after knickpoint propagation. Incision rates were obtained from the concentrations of cosmogenic 10Be in samples extracted from the river bed. The results indicate that incision rates are not re-established at an expected value of ≈ 0.1 m/k yr after knickpoint migration. Rather, incision rates below the knickpoint remain somewhat elevated (≈ 0.5 m/k yr) reflecting: (1) ongoing base-level fall, and/or (2) the propagation of younger knickpoints (< 13.6 ka) in those transient reaches. The cosmogenic-derived incision rates were tested with different bedrock incision rules. The results indicate that the stream power model is a good predictor for channel incision, even for the case of small catchments. In chapter 7 the conclusions of this research are provided.

One of the most catastrophic natural hazards which can devastate coastal zone communities is the tsunami. The risk of tsunami devastation can be mitigated by reconstruction and quantification of past tsunamis, but this requires identification and analysis of past tsunami magnitudes and dates even from historical times. The interpretation of geological records of tsunamigenic deposits is the core theme explored in this thesis for the characterisation of palaeotsunamis. Three key elements: identification of palaeotsunamites, dating their deposition and determination of magnitude are needed for reconstruction and quantification of palaeotsunamis. While several studies have described criteria for identification of tsunamigenic sediments, much less research has been carried out on reconstruction of palaeotsunamis. Sediment characteristics, their depositional configuration and extent of the inundation area on the coast give infOlmation on hydrodynamic conditions of tsunami waves. This study has developed a method to estimate tsunami risk by reconstructing and quantifying palaeotsunamis from tsunamigenic sediments on the Sri Lankan coast rising sedimentological and paleontological characteristics, Ground Penetrating Radar (GPR), and optically stimulated luminescence (OSL) dating techniques. The 2004 tsunami records were used as a control for the study. Distinctive tsunamigenic sediment signatures were recognised. Three palaeotsunami events were identified and dated at ISO (Krakatua), 2550±190 and 3170±320 years BP and correlated with historical and archaeological records. The recurrence interval of c 600 years postulated for the Indian Ocean was confirmed by this study and the oldest event recorded to date in the Indian Ocean was recognised at 3170±320BP. The method developed here based on reconstruction of palaeotsunamis using sedimentological records, GPR and OSL techniques enables estimation of inundation distance, recurrence interval and consequently the wave characteristics of palaeotsunamis which can be used to estimate tsunami risk for any coast.

Postglacial bedrock river erosion is likely to be a major control on the evolution of deglaciated landscapes. This study provides a quantitative assessment of bedrock channel change in a postglacial, post-orogenic terrain, encompassing the long-term evolution of bedrock channel distribution, geometry and the timing and rate of fluvial incision. In the NW Scottish Highlands, fluvial incision is focused on steep valley headwalls and at knickpoints formed at inherited glacial valley-floor steps (riegels). Holocene average incision rates of 0.4 – 1.3 m/kyr were measured using cosmogenic surface exposure dating (10-Be) at five strath terrace sites. Incision rates of 0.1 m/kyr were quantified from active channel beds and are lower than the Holocene average. This finding is consistent with a paraglacial decline in sediment supply being responsible for a reduction in fluvial incision in detachment-limited channels. Further support for a paraglacial sediment influence on bedrock channels is found in the long-term increase in the proportion of bedrock-exposure, reflecting a decrease in the critical slope threshold for the alluvial to bedrock channel transition. In reaches that have undergone a switch from alluvial to bedrock channel conditions, the onset of fluvial incision into bedrock was found to lag deglaciation by 2 – 4 kyr, suggesting that a substantial reduction in sediment availability occurred within several thousand years of ice retreat. Hydraulic conditions and substrate resistance are also major controls on the distribution and geometry of bedrock channels, and the rate of fluvial incision, in the NW Highlands. The geometry of both bedrock and alluvial channels was found to be strongly hydraulically scaled, with bedrock channels significantly narrower than coarse-grained alluvial channels. Lithology also governs the critical slope for alluvial to bedrock channel-transition; resistant metasedimentary bedrock produces relatively coarse-grained bed material with a high threshold for sediment entrainment, meaning that alluvial channels occur up to comparatively steep channel slopes. Lithological resistance also constrains the process and rate of fluvial incision. A new lithological resistance index, the ratio of joint spacing to intact rock strength, successfully discriminates between abrasion and plucking dominated channels and is non-linearly related to incision rate. The pulse of postglacial incision in bedrock channels has resulted in 2 – 8 m of entrenchment into valley floors since deglaciation. Bedrock channels narrow during entrenchment, achieving a consistent hydraulic geometry when entrenched to between 1 and 2 times the bankfull flow depth. Width adjustment occurs within 8 – 17 kyr of ice retreat, but adjustment of channel slope takes considerably longer and the long profiles of NW Highland rivers remain strongly glacially conditioned. Entrenchment disconnects channels from floodplains and may have contributed to the decline in paraglacial sediment flux, suggesting that fluvial incision may be a self-limiting process in post-orogenic postglacial terrains.

The relationships between the land management system and the town planning system play a crucial role in the process of land development, especially as Henan province is experiencing accelerated industrialization. In recent years, China has adjusted its land management system. The findings of the research show that the current land management system and town planning system of China are not compatible with each other when faced with the rapid industrialization of the core towns in Henan province. Furthermore, the incompatibilities between China’s current land management system and town planning system have impeded the growth of the industrial scale and raised the costs of industrialization. There are two main reasons which cause the incompatibilities between these two systems, namely the contrasting characteristics between the town planning system and land management system and the different objectives between the local governments and the central government of China. The incompatibilities between China’s town planning system and land management system are rooted in and shaped by the central-local relations.

Probabilistic forecasting plays a pivotal role both in the application and in the advancement of geophysical modelling. Operational techniques and modelling methodologies are examined critically in this thesis and suggestions for improvement are made; potential improvements are illustrated in low-dimensional chaotic systems of nonlinear equations. Atlantic basin hurricane forecasting and forecast evaluation methodologies on daily to multi-annual timescales provide the primary focus of application and real world illustration. Atlantic basin hurricanes have attracted much attention from the scientific and private sector communities as well as from the general public due to their potential for devastation to life and property, and speculation on increasing trends in hurricane activity. Current approaches to modelling, prediction and forecast evaluation employed in operational hurricane forecasting are critiqued, followed by recommendations for best-practice techniques. The applicability of these insights extends far beyond the forecasting of hurricanes. Hurricane data analysis and forecast output is based on small-number count data sourced from a small-sample historical archive; analysis benefits from specialised statistical methods which are adapted to this particular problem. The challenges and opportunities arising in hurricane statistical analysis and forecasting posed by small-number, small-sample, and, in particular, by serially dependent data are clarified. This will allow analysts and forecasters alike access to more appropriate statistical methodologies. Novel statistical forecasting techniques are introduced for seasonal hurricane prediction. In addition, a range of linear and non-linear techniques for analysis of hurricane count data are applied for the first time along with an innovative algorithmic approach for the statistical inference of regression model coefficients. A real-time outlook for the 2013 hurricane season is presented, along with a methodology to support a running (re)analysis for National Hurricane Center 48 hour forecasts in 2013; the focus here is on if, and if so how, to improve forecast effectiveness by “recalibrating” the raw forecasts in real time. In this case, it is revealed that recalibration does not improve forecast performance, and that, across years, it can be detrimental. In short, a new statistical framework is proposed for evaluating and interpreting forecast reliability, forecast skill, and forecast value to provide a sound basis for constructing and utilising operational event predictions. This novel framework is then illustrated in the specific context of hurricane prediction. Proposed methods of forecast recalibration in the context of both a low-dimensional dynamical system and operational hurricane forecasting are employed to illustrate methods for improving resource allocation distinguishing, for example, scenarios where forecast recalibration is effective from those where resources would be better dedicated towards improving forecast techniques. A novel approach to robust statistical identification of the weakest links in the complex chain leading to probabilistic prediction of nonlinear systems is presented, and its application demonstrated in both numerical studies and operational systems.

This study seeks to determine the extent to which chemostratigraphy can supplement other stratigraphic tools in determining the effects of climate change in loess-palaeosol sequences. Geochemical change has been used to illuminate the effects of glacial/interglacial climate change in Chinese loess-palaeosol sequences; less work has been done to examine the effects of stadial/interstadial climate change and little work has been carried out in Europe on either aspect. Two loess-palaeosol sites were selected in northwestern Europe that were known to provide good records of the last ice age. This study has produced detailed descriptions of variation in concentrations of the major, minor and rare-earth elements. These are compared with variation in the standard sedimentological parameters (grain size, organic carbon content and carbonate content) and in enviromagnetic characteristics, which are accepted as palaeoclimate proxies. The existing polymineral-based luminescence chronology at each site has been enhanced using a quartz-based approach,which broadly confirms the accuracy of previous ages and generates estimates of increased precision. That chronology facilitates comparison of these analyses with evidence for palaeoclimatic: change in the wider record, including GRIP ice-core data. Grain size is shown to be a strong proxy for variation in mean wind strength and in accumulation rates which can be correlated in detail with GRIP. The study has established that geochemical heterogeneity now apparent at the sites has been imposed by weathering. Carbonate weathering is a reliable indication of major pedogenic episodes but its detailed interpretation is tempered by carbonate mobility. Silicate weathering occurs at lower intensity than carbonate weathering but is a permanent record since silicates are not subject to reprecipitation under these conditions. The study concludes that chemostratigraphy is a climatological proxy, detecting periods of significant amelioration. It is not a replacement for conventional proxies, it complements them and provides additional evidence upon which climatic reconstructions can be made.

This thesis develops a chronology of ice retreat in the Monadhliath Mountains (Scotland) and Rodna Mountains (Romania) during the late Pleistocene using glacial geomorphology and surface exposure dating with cosmogenic 10Be. In the Monadhliath Mountains, 10Be exposure ages indicate deglaciation of the Last Devensian ice sheet at 15.1 ka (n = 2). Boulders from moraines in three Monadhliath cirques yielded exposure ages between 11.8 ka and 9.8 ka (470 – 600 m), suggesting that a Late Glacial readvance occurred during the Younger Dryas stadial (n = 9). The limited extent of these YD glaciers in the Monadhliath Mountains is explained in terms of the drier climate experienced by the eastern part of the Central Highland ice cap, but also in terms of local factors such as topography and snow blow. The resulting glacial reconstruction largely confirms that a SW to NE precipitation gradient dominated Scotland during the Younger Dryas. In the Romanian Carpathians, located at the southern periphery of the NW European ice sheet, there was only limited coverage of ice, mostly at higher elevations in the form of mountain glaciers. Field evidence suggests that during the last local maximum glaciation ice reached lower elevations than previously suggested in the Rodna Mountains. Glacially transported boulders were abandoned at 37.2 – 26.6 ka (n = 4) at an elevation of ~900 m. Glacial erratics and bedrock samples (n = 27) provide a consistent chronology for deglaciation during the Lateglacial, suggesting that ice retreated towards higher ground between 18.3 – 13.2 ka (1100 – 1800 m altitude). Final deglaciation took place at 12.5 - 11.2 ka (n = 9). These new chronologies are compared to other climate archives in Europe and the climatic oscillations recorded in the North Atlantic region. This analysis increases our understanding of past atmospheric circulation across Europe, and gives insights into the climatic forcing mechanisms during the last maximum extent of ice sheets and glaciers. During the last glacial episodes, the pattern of climate cooling from the western high latitudes towards the eastern mid latitudes was complicated, triggering different responses in local climates that appear to have been out of phase with the broader north-western European trend. Located in the NW Europe, Scotland was influenced by the wetter and colder conditions from the Atlantic which led to the expansion of the British Ice sheet during the global Last Glacial Maximum (LGM). However, smaller ice masses located further southwards and south-eastwards of the European ice sheet responded faster to the climatic oscillations in the North Atlantic region. During the LGM, the southward repositioning of the Polar Front and the presence of the ice sheet changed the atmospheric circulation across Europe. There was limited supply of moisture to the Rodna Mountains, especially because of blocking by the eastern Siberian high pressure system, and the glaciers experienced a slow retreat in a very cold and dry environment. However, a more synchronous Younger Dryas is likely to have occurred due to a more northern position of the Polar Front. This allowed for stronger wet and cold westerly winds to reach most of Europe at the same time.

The study used continuously monitored, high resolution turbidity, ammonia, rainfall and flow data from EA UK. Urban storm events were not systematically characterised previously leading to gaps in process understanding; previous studies used short time periods and with most of them formed on single gauges. Aimed at improving understanding with novel contributions, the objectives were characterising the events, finding their seasonal influence and the spatial scale effect on turbidity patterns. Universally adaptable quantified events characterisation and classification were developed yielding single, double and multiple events. Double and multiple events together was more than single events for both smaller and larger catchments. Thus, analysing only single events could miss key dynamics of multiple events which showed significant increases in turbidity. More anticlockwise events than clockwise were found. Anticlockwise events decreased and clockwise increased from single to multiple events. Events with more number of turbidity than discharge peaks were found. Seasonally, most attributes as well as high urban extent and effluent spillage showed significant effects on turbidity mostly in summer and autumn. All seasons but spring with more anticlockwise than clockwise events had more low flows. Winter had the highest anticlockwise events, possibly because of its wider areal rain event extent, high number of low flows as well as more distal runoff sources. In the spatial scale studies, more single events in the smaller and more multiple events in the larger catchments as well as more anticlockwise events in the smaller and more clockwise events in the larger catchment were found.