Far-future hydrology will differentially change the phosphorus transfer continuum.

Climate change is likely to exacerbate land to water phosphorus (P) transfers, causing a degradation of water quality in freshwater bodies in Northwestern Europe. Planning for mitigation measures requires an understanding of P loss processes under such conditions. This study assesses how climate induced changes to hydrology will likely influence the P transfer continuum in six contrasting river catchments using Irish national observatories as exemplars.

Soil erosion, sediment sources, connectivity and suspended sediment yields in UK temperate agricultural catchments: Discrepancies and reconciliation of field-based measurements.

Robust understanding of the fine-grained sediment cascades of temperate agricultural catchments is essential for supporting targeted management for addressing the widely reported sediment problem. Within the UK, many independent field-based measurements of soil erosion, sediment sources and catchment suspended sediment yields have been published. However, attempts to review and assess the compatibility of these measurements are limited.

Grazing livestock move by Lévy walks: Implications for soil health and environment.

Grazing livestock plays an important role in the context of food security, agricultural sustainability and climate change. Understanding how livestock move and interact with their environment may offer new insights on how grazing practices impact soil and ecosystem functions at spatial and temporal scales where knowledge is currently limited. We characterized daily and seasonal grazing patterns using Global Positioning System (GPS) data from two grazing strategies: conventionally- and rotationally-grazed pastures.

A reconnaissance survey of channel bank particulate phosphorus concentrations, controls and estimated contributions to riverine loads across England.

Channel banks can contribute a significant proportion of fine-grained (<63 μm) sediment to rivers, thereby also contributing to riverine total particulate phosphorus loads. Improving water quality through better agricultural practices alone can be difficult since the contributions from non-agricultural sources, including channel banks, can generate a 'spatial mismatch' between the efficacy of best management applied on farms and the likelihood of meeting environmental objectives. Our study undertook a reconnaissance survey ( = 76 sites each with 3 profiles sampled) to determine the total phosphorus (TP) concentrations of channel banks across England and to determine if TP content can be predicted using readily accessible secondary data.

Using the colour of recent overbank sediment deposits in two large catchments to determine sediment sources for targeting mitigation of catchment-specific management issues.

The effective management of sediment losses in large river systems is essential for maintaining the water resources and ecosystem services they provide. However, budgetary, and logistical constraints often mean that the understanding of catchment sediment dynamics necessary to deliver targeted management is unavailable. This study trials the collection of accessible recently deposited overbank sediment and the measurement of its colour using an office document scanner to identify the evolution of sediment sources rapidly and inexpensively in two large river catchments in the UK.

Abdominal aortic aneurysm rupture presenting with focal weakness and altered mental status: a case report.

Background: Abdominal aortic aneurysms (AAA) can present asymptomatically and may be found through routine screening or seen incidentally on imaging. Rupture due to weaking of the aortic wall is the main complication of an AAA and leads to approximately 200,000 deaths annually worldwide. Clinically, AAA rupture most frequently presents with abdominal and/or back pain, pulsatile abdominal mass, and hypotension.

A rapid and inexpensive colour-based sediment tracing method incorporating hydrogen peroxide sample treatment as an alternative to quantitative source fingerprinting for catchment management.

Accessible sediment provenance information is highly desirable for guiding targeted interventions for reducing excess diffuse agricultural sediment losses to water. Conventional sediment source fingerprinting methods can provide this information, but at high cost, thereby limiting their widespread application for catchment management. The use of sediment colour measured using an office document scanner represents an easy, fast, and inexpensive alternative method to trace sediment sources.

Does cattle and sheep grazing under best management significantly elevate sediment losses? Evidence from the North Wyke Farm Platform, UK.

Purpose: Intensive livestock grazing has been associated with an increased risk of soil erosion and concomitant negative impacts on the ecological status of watercourses. Whilst various mitigation options are promoted for reducing livestock impacts, there is a paucity of data on the relationship between stocking rates and quantified sediment losses. This evidence gap means there is uncertainty regarding the cost-benefit of policy preferred best management.

The potential for colour to provide a robust alternative to high-cost sediment source fingerprinting: Assessment using eight catchments in England.

Excess diffuse fine sediment losses from agriculture are associated with a reduction in the ecological status of lakes and rivers. Agri-environment initiatives aim to help reduce these excessive losses through targeted on-farm advice and capital grants. However, to deliver optimum cost-benefit such initiatives must target the most important sediment sources.

Current advisory interventions for grazing ruminant farming cannot close exceedance of modern background sediment loss - Assessment using an instrumented farm platform and modelled scaling out.

Water quality impairment by elevated sediment loss is a pervasive problem for global water resources. Sediment management targets identify exceedance or the sediment loss 'gap' requiring mitigation. In the UK, palaeo-limnological reconstruction of sediment loss during the 100-150 years pre-dating the post-World War II intensification of agriculture, has identified management targets (0.

Sediment source fingerprinting: benchmarking recent outputs, remaining challenges and emerging themes.

Purpose: This review of sediment source fingerprinting assesses the current state-of-the-art, remaining challenges and emerging themes. It combines inputs from international scientists either with track records in the approach or with expertise relevant to progressing the science.

Methods: Web of Science and Google Scholar were used to review published papers spanning the period 2013-2019, inclusive, to confirm publication trends in quantities of papers by study area country and the types of tracers used.

Sediment loss in response to scheduled pasture ploughing and reseeding: The importance of soil moisture content in controlling risk.

Soil water regimes have been shown to have important implications for the erosion risks associated with land management decisions. Despite this, there remains a paucity of information on soil moisture thresholds for farm management operations including the periodic ploughing and reseeding of improved pasture used for ruminant farming. Against this background, this study analysed sediment loss monitored on a heavily instrumented farm platform, in SW England, over four phases of ploughing and reseeding.

The representation of sediment source group tracer distributions in Monte Carlo uncertainty routines for fingerprinting: An analysis of accuracy and precision using data for four contrasting catchments.

Previous studies comparing sediment fingerprinting un-mixing models report large differences in their accuracy. The representation of tracer concentrations in source groups is perhaps the largest difference between published studies. However, the importance of decisions concerning the representation of tracer distributions has not been explored explicitly.

Storm dust source fingerprinting for different particle size fractions using colour and magnetic susceptibility and a Bayesian un-mixing model.

In the context of the continued increased global uptake of fingerprinting procedures to explore fluvial sediment sources, far less attention has been paid to dust source tracing and especially using different particle size fractions and low-cost tracers such as colour and magnetic susceptibility. The objective of this study, therefore, was to apportion local dust storm source contributions for the < 63-μm and 63-125-μm fractions of dust samples in a case study in central Iran. Colour and magnetic susceptibility properties were measured on 62 source samples and six dust storm samples.

Field-based determination of controls on runoff and fine sediment generation from lowland grazing livestock fields.

Compared with arable land, there is a paucity of field-based measurements of erosion rates and controls for lowland temperate grassland supporting ruminant agriculture. Despite this evidence gap, reducing diffuse fine sediment pollution from intensively farmed grassland has been recognised as essential for improving compliance with water quality targets. Improved information on erosion rates and controls within intensively managed lowland grazing livestock systems are prerequisites for informing best management practices for soil and water resource conservation.

The sources and dynamics of fine-grained sediment degrading the Freshwater Pearl Mussel (Margaritifera margaritifera) beds of the River Torridge, Devon, UK.

The Freshwater Pearl Mussel (Margaritifera margaritifera) is an endangered organism across its entire range. It has a complex life cycle and stringent habitat requirements and is therefore an indicator species for the general ecosystem health of host rivers. Whereas historical intensive pearl fishing contributed to population declines, excess nutrient and sediment loss associated with current land use pressures in host river catchments, including modern intensive farming practices, are now highlighted as primary contributory factors.

Tracing catchment fine sediment sources using the new SIFT (SedIment Fingerprinting Tool) open source software.

The mitigation of diffuse sediment pollution requires reliable provenance information so that measures can be targeted. Sediment source fingerprinting represents one approach for supporting these needs, but recent methodological developments have resulted in an increasing complexity of data processing methods rendering the approach less accessible to non-specialists. A comprehensive new software programme (SIFT; SedIment Fingerprinting Tool) has therefore been developed which guides the user through critical data analysis decisions and automates all calculations.

Magnetic susceptibility as a simple tracer for fluvial sediment source ascription during storm events.

Sediment tracing using a single tracer, low frequency magnetic susceptibility (X), was used to apportion suspended sediment to geologically defined source areas and to interpret sediment source changes during flood events in the degraded catchment of the Vuvu River, a headwater tributary of the Mzimbubu River, South Africa. The method was tested as a simple tool for use by catchment managers concerned with controlling erosion. The geology of the 58 km catchment comprises two distinct formations: basalt in the upper catchment with a characteristically high magnetic susceptibility and shales with a low magnetic susceptibility in the lower catchment.

Sediment source fingerprinting as an aid to catchment management: A review of the current state of knowledge and a methodological decision-tree for end-users.

The growing awareness of the environmental significance of fine-grained sediment fluxes through catchment systems continues to underscore the need for reliable information on the principal sources of this material. Source estimates are difficult to obtain using traditional monitoring techniques, but sediment source fingerprinting or tracing procedures, have emerged as a potentially valuable alternative. Despite the rapidly increasing numbers of studies reporting the use of sediment source fingerprinting, several key challenges and uncertainties continue to hamper consensus among the international scientific community on key components of the existing methodological procedures.

The impact of catchment source group classification on the accuracy of sediment fingerprinting outputs.

The objective classification of sediment source groups is at present an under-investigated aspect of source tracing studies, which has the potential to statistically improve discrimination between sediment sources and reduce uncertainty. This paper investigates this potential using three different source group classification schemes. The first classification scheme was simple surface and subsurface groupings (Scheme 1).

Feedback effects of estradiol and progesterone on ovulation and fertility of dairy cows after gonadotropin-releasing hormone-induced release of luteinizing hormone.

An experiment was conducted with the objective to determine the effects of estradiol, progesterone, presence of a corpus luteum (CL), and size of a dominant follicle on the characteristics and patterns of GnRH-induced LH release and subsequent ovulation during a timed artificial insemination (TAI) program, or a combination of these. In 70 lactating dairy cows, a total of 163 blood collection periods resulting in a GnRH-induced LH release were analyzed. Concentrations of LH were measured in hourly samples (0 through 6 h after GnRH) during each of the blood collection periods, whereas concentrations of progesterone and estradiol were measured in the sample before GnRH treatment (0 h).

The use of an ordinary colour scanner to fingerprint sediment sources in the South African Karoo.

The widespread adoption of sediment fingerprinting methodologies for the purpose of catchment management has been restricted by the high cost of tracer analysis as well as the potential for significant uncertainties to be present in results. Sediment colour has shown potential to be an inexpensive tracer able to discriminate between sediment sources. However, at present colour has not been demonstrated to be conservative during sediment erosion and transport.

Concentrations of luteinizing hormone and ovulatory responses in dairy cows before timed artificial insemination.

The objective was to determine the incidence of LH surges and ovulatory responses in lactating dairy cows enrolled in a timed artificial insemination (TAI) program. Cows were assigned randomly to 2 presynchronization treatments: (1) Pre10 (n=37): 2 injections of PGF2α (PG; PG-1 and PG-2) 14 d apart (Presynch); or (2) PG-3-G (n=33): one 25-mg injection of PG (Pre-PG) administered 3 d before a 100-µg GnRH injection (Pre-GnRH). Ten days after PG-2 or Pre-PG, all cows were enrolled in a 7-d Ovsynch TAI program [injection of GnRH (GnRH-1) 7 d before PG (PG-3) and GnRH (GnRH-2) administered at either 56 or 72 h after PG-3; TAI at 72 h].

Five-day resynchronization programs in dairy cows including presynchronization and progesterone at two stages following artificial insemination.

Two experiments were conducted to assess pregnancy outcomes after a 5-d Ovsynch-56 Resynch program [RES; GnRH injection (d 0) 5 d before and 56 h after the first of 2 PG injections on d 5 and 6, and timed artificial insemination (TAI) on d 8] with or without a 5-d progesterone-releasing intravaginal controlled internal drug release (CIDR) insert applied at d 0. In experiment 1, nonpregnant cows were enrolled on d 35 post-AI: d-35 RES-CON (n=454) or d-35 RES-CIDR (n=495). Blood was collected on d 0 for progesterone assay.

Studies towards the synthesis of medermycin via Dötz benzannulation.

The C-arylglycosides are available in enantiomerically pure form via the Dötz benzannulation reaction between Fischer alkenyl chromium carbene complexes and alkynes; it also could be converted to a precursor of medermycin by O-carbamate directed ipso bromination and nitrile substitution in good overall yields.