538 research outputs found
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Climate change, agriculture and Fairtrade: identifying the challenges and opportunities
This paper presents the findings of a study commissioned by the UK's Fairtrade Foundation on the implications of climate change for agricultural producers in Fairtrade value chains
Reputation and accountability: where are the checks and balances with social media?
How have changes in the media landscape have affected the practice of reputation management? Public Relations Executive Tim Burt says that the proliferation of social media has greatly limited the amount of editorial control that can be exercised over the dissemination of information. Burt argues that social media have eroded the system of âchecks and balancesâ that historically governed the reporting process, a development that has (unsurprisingly) led to high levels of anxiety among CEOs. It has made it more difficult for Burt to manage the reputations of his corporate clientele, but he is also cautiously optimistic regarding how a diffuse media environment might increase democratic accountability. Polis Intern Kyle Bowen takes up some of the issues that emerged from the latest Polis Media Agenda Talk
The global transformation of geomorphology
This chapter reviews the various developments in geomorphology in terms of institutions, journals, textbooks, research stations, etc. Among the institutions discussed are the Binghamton Geomorphology Symposium, the Geological Society of America Quaternary Geology and Geomorphology Division, the Association of American Geographers Geomorphology Specialty Group, the British Geomorphological Research Group, the IGU Commission on Measurements, Theory and Application in Geomorphology (COMTAG), the International Association of Geomorphologists, the European Geosciences Union (EGU), the American Geophysical Union (AGU), the International Quaternary Association, and the International Conference on Aeolian Research. Many countries established their own national bodies. A number of new journals appeared, including Catena, Earth Surface Processes and Landforms, GĂ©omorphologie, and Geomorphology. In addition, during the closing decades of the twentieth century there was a proliferation of textbooks in geomorphology. One development was that geomorphological research was promoted by the establishment of research stations. These permitted long-term monitoring and provided bases for sustained investigations. The study of fluvial processes was much encouraged in the United States at USDA Forest Service research basins (known as âwatershedsâ in the USA) such as the Hubbard Brook Experimental Forest (New Hampshire), Coweeta Hydrologic Laboratory (North Carolina) and the H.J. Andrews Experimental Forest (Oregon). The Royal Geographical Society (with the Institute of British Geographers) organized ambitious research projects in collaboration with host nations. Various US government departments supported much geomorphological research in various parts of the world. Some European countries fostered overseas geomorphological research and created missions. Notable was the work of ORSTOM (Office de la Recherche Scientifique et Technique Outre-mer) in former francophone colonies. In the post-war years, and as independence approached and then occurred, new universities were established in Africa. These employed expatriate geomorphologists and also trained up a new generation of indigenous scholars. The decades since the 1960s have been a period of space exploration and the development of remote sensing. This has had important implications for geomorphology. The period also saw the onset of the digital age and the beginning of the World Wide Web's influence on teaching and research. Applied research became increasingly important. A major cause for international and cross-disciplinary co-operation during the period was the emergence of geoarchaeology. Finally, since the 1950s, an increasing number of women have made important contributions to the discipline
River water temperature demonstrates resistance to longâterm air temperature change
Ecosystem health and water quality of rivers are dependent on their temperature. With ongoing human-induced climate change causing increases in air temperature across the globe, it is anticipated the stream temperatures will rise tooâin turn increasing the rates of biogeochemical stream processes and potentially threatening the viability and health of aquatic organisms. To understand the relationship between climate change and stream temperature response, the longer the records that can be analysed, the more the robust the analysis for detecting change. In this study, we analyse records from 263 catchments from across the United Kingdom for 45âyears from 1974 to 2019 to assess the link between air temperature and stream temperature change. To give the most precise analysis of these long records, Bayesian hierarchical modelling was used and showed that: (i) The Bayesian hierarchical approach was 59% more precise, that is, reduced uncertainty on long-term trends, than using simple linear regression. (ii) The increase in annual average air temperature over 45âyears across the United Kingdom showed no significant differences between 22 weather stations and gave a 45-year change of 1.35â±â0.9°C. (iii) Trends in annual mean stream temperature change varied from â2.3 °C to 2.0 °C over 45 years, with the mean over 263 sites being 0.5 °C over 45 years. (iv) 1% of rivers showed a stream temperature trend significantly greater than the air temperature trend but 3% of sites showed a stream temperature trend significantly lower than zero. (v) 74% of all river sites showed no significant monotonic trend, either positive or negative, in water temperature even after 45âyears. The observed declines in stream temperature could be ascribed to the closures of thermoelectric power stations but it is unclear why the stream temperature at some sites has risen faster than air temperature. The study shows that mean river temperature was well buffered against changes in air temperatureâa 1°C rise in air temperature giving 0.37°C in mean stream temperature
Chemical Oxygen Demand as a Measure of Fluvial Organic Matter Oxidation State
The oxidative ratio (OR) of the terrestrial biosphere is directly related to the size of the terrestrial biosphere carbon sink. In turn, OR of naturally occurring organic matter can be directly related to the oxidation state of the carbon in naturally occurring organic matter (Cox). Chemical oxygen demand (COD) is a widely measured water quality parameter that has been used as a shortâterm substitute for the biochemical oxygen demand (BOD). Here, we propose that if the concentration of reduced species is known, then COD measurement can be used to assess the oxidation state (Cox) of fluvial organic C. Using a Bayesian hierarchical modeling approach, this study analyzed 21 years of water quality monitoring across England to calculate Cox of fluvial organic matter. The study showed that (a) COD could not be considered separately from the reduced species (e.g., NH4) commonly occurring in freshwater water samples, but it was still possible to calculate the Cox of dissolved organic carbon (DOC) and particulate organic carbon (POC). (b) The median Cox of DOC was 0.23 with a 95th percentile range of â0.1 to 0.4. (c) The median Cox of POC was 0.20 with a 95th percentile range of 0.03â0.37. (d) The estimated Cox in fluvial systems confirms that BOD is decoupled from the production of CO2. Including new Cox estimates in the global estimate of OR gives a new median value of 1.059 with a 95th percentile range of 1.047â1.071, giving the annual flux of CO2 to land (fland) of 1.45 ± 0.1 Gt C/year
Human impact on long-term organic carbon export to rivers
Anthropogenic landscape alterations have increased global carbon transported by rivers to oceans since preindustrial times. Few suitable observational data sets exist to distinguish different drivers of carbon increase, given that alterations only reveal their impact on fluvial dissolved organic carbon (DOC) over long time periods. We use the world's longest record of DOC concentrations (130 years) to identify key drivers of DOC change in the Thames basin (UK). We show that 90% of the long-term rise in fluvial DOC is explained by increased urbanization, which released to the river 671 kt C over the entire period. This source of carbon is linked to rising population, due to increased sewage effluent. Soil disturbance from land use change explained shorter-term fluvial responses. The largest land use disturbance was during the Second World War, when almost half the grassland area in the catchment was converted into arable land, which released 45 kt C from soils to the river. Carbon that had built up in soils over decades was released to the river in only a few years. Our work suggests that widespread population growth may have a greater influence on fluvial DOC trends than previously thought
The problem of underpowered rivers
This study has hypothesized that for many rivers the tradeâoff between flow accumulation and the decrease in slope along channel length means that stream power increases downstream and, moreover, that given the low slope angles in headwater and lowâorder streams, they would have insufficient stream power to erode let alone transport sediment. The study considered the stream power profile, the particle travel distances and the application of the Hjulström curve based on the velocity profile of nine, large UK catchments. The study showed that: Some rivers never showed a maximum in their longitudinal stream power profile, implying that some rivers never develop a deposition zone before they discharge at the tidal limit. Particle travel distances during a bankfull discharge event showed that for some rivers 91% of the upper main channel would not be cleared of sediment. Furthermore, while some rivers could transport a 2âmm particle their entire length in one bankfull event, for another river it would take 89 such events. The Hjulström curve shows that for three of the study rivers the upper 20âkm of the river was not capable of eroding a 2 ÎŒm particle. The study has shown that for all rivers studied, erosion is focused downstream and deposition upstream. Many UK rivers have a dead zone where, on time scales of the order of centuries, no erosion or transport occurs and erosion only occurs in the lower courses of the channel where discharge rather than slope dominates â we propose these as underpowered rivers
Fluxes of inorganic carbon from two forested catchments in the Appalachian Mountains
Abstract: This study uses long-term records of stream chemistry, discharge and air temperature from two neighbouring forested catchments in the southern Appalachians in order to calculate production of dissolved CO 2 and dissolved inorganic carbon (DIC). One of the pair of catchments was clear-felled during the period of the study. The study shows that: (1) areal production rates of both dissolved CO 2 and DIC are similar between the two catchments even during and immediately after the period of clear-felling; (2) flux of total inorganic carbon (dissolved CO 2 C DIC) rises dramatically in response to a catchment-wide acidification event; (3) DIC and dissolved CO 2 are dominantly released on the old water portion of the discharge and concentrations peak in the early autumn when flows in the study catchments are at their lowest; (4) total fluvial carbon flux from the clear-felled catchment is 11Ă6 t km 2 year 1 and for the control catchment is 11Ă4 t km 2 year 1 . The total inorganic carbon flux represents 69% of the total fluvial carbon flux. The method presented in the study provides a useful way of estimating inorganic carbon flux from a catchment without detailed gas monitoring. The time series of dissolved CO 2 at emergence to the stream can also be a proxy for the soil flux of CO 2
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IMproving the practice of intrapartum electronic fetal heart rate MOnitoring with cardiotocography for safer childbirth (the IMMO programme): protocol for a qualitative study.
INTRODUCTION: Suboptimal electronic fetal heart rate monitoring (EFM) in labour using cardiotocography (CTG) has been identified as one of the most common causes of avoidable harm in maternity care. Training staff is a frequently proposed solution to reduce harm. However, current approaches to training are heterogeneous in content and format, making it difficult to assess effectiveness. Technological solutions, such as digital decision support, have not yet demonstrated improved outcomes. Effective improvement strategies require in-depth understanding of the technical and social mechanisms underpinning the EFM process. The aim of this study is to advance current knowledge of the types of errors, hazards and failure modes in the process of classifying, interpreting and responding to CTG traces. This study is part of a broader research programme aimed at developing and testing an intervention to improve intrapartum EFM. METHODS AND ANALYSIS: The study is organised into two workstreams. First, we will conduct observations and interviews in three UK maternity units to gain an in-depth understanding of how intrapartum EFM is performed in routine clinical practice. Data analysis will combine the insights of an ethnographic approach (focused on the social norms and interactions, values and meanings that appear to be linked with the process of EFM) with a systems thinking approach (focused on modelling processes, actors and their interactions). Second, we will use risk analysis techniques to develop a framework of the errors, hazards and failure modes that affect intrapartum EFM. ETHICS AND DISSEMINATION: This study has been approved by the West Midlands-South Birmingham Research Ethics Committee, reference number: 18/WM/0292. Dissemination will take the form of academic articles in peer-reviewed journals and conferences, along with tailored communication with various stakeholders in maternity care
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