A novel application of remote sensing for modelling impacts of tree shading on water quality

Uncertainty in capturing the effects of riparian tree shade for assessment of algal growth rates and water temperature hinders the predictive capability of models applied for river basin management. Using photogrammetry-derived tree canopy data, we quantified hourly shade along the River Thames (UK) and used it to estimate the reduction in the amount of direct radiation reaching the water surface. In addition we tested the suitability of freely-available LIDAR data to map ground elevation. Following removal of buildings and objects other than trees from the LIDAR dataset, results revealed considerable differences between photogrammetry- and LIDAR-derived methods in variables including mean canopy height (10.5 m and 4.0 m respectively), percentage occupancy of riparian zones by trees (45% and 16% respectively) and mid-summer fractional penetration of direct radiation (65% and 76% respectively). The generated data on daily direct radiation for 2010 were used as input to a river network water quality model (QUESTOR). Impacts of tree shading were assessed in terms of upper quartile levels, revealing substantial differences in indicators such as biochemical oxygen demand (BOD) (1.58–2.19 mg L−1 respectively) and water temperature (20.1 and 21.2 °C respectively) between ‘shaded’ and ‘non-shaded’ radiation inputs. Whilst the differences in canopy height and extent derived by the two methods are appreciable they only make small differences to water quality in the Thames. However such differences may prove more critical in smaller rivers. We highlight the importance of accurate estimation of shading in water quality modelling and recommend use of high resolution remotely sensed spatial data to characterise riparian canopies. Our paper illustrates how it is now possible to make better reach scale estimates of shade and make aggregations of these for use at river basin scale. This will allow provision of more effective guidance for riparian management programmes than currently possible. This is important to support adaptation to future warming and maintenance of water quality standards

Review of methods for assessing deposition of reactive nitrogen pollutants across complex terrain with focus on the UK

This review is a summary of the most up-to-date knowledge regarding assessment of atmospheric deposition of reactive nitrogen (Nr) pollutants across complex terrain in the UK. Progress in the understanding of the mechanisms and quantification of Nr deposition in areas of complex topography is slow, as no concerted attempts to measure the components of Nr in complex terrain have been made in the last decade. This is likely due to the inherent complexity of the atmospheric processes and chemical interactions which contribute to deposition in these areas. More than 300 studies have been reviewed, and we have consulted with a panel of international experts which we assembled for that purpose. We report here on key findings and knowledge gaps identified regarding measurement and modelling techniques used to quantify deposition of Nr across complex terrain in the UK, which depending on definition, may represent up to 60% of land coverage across Great Britain. The large body of peer reviewed papers, reports and other items reviewed in this study has highlighted both the strengths and weaknesses in the tools available to scientists, regulators and policy makers. This review highlights that there is no coherent global research effort to constrain the uncertainties in Nr deposition over complex terrain, despite the clearly identified risk of N deposition to ecosystems and water quality. All evidence identified that enhanced Nr deposition across complex terrain occurs, and magnitude of the enhancement is not known; however, there are major uncertainties particularly in the differences between modelled and measured wet deposition in complex terrain and representing accurate surface interactions in models. Using simplified estimates for Nr deposition, based on current understanding of current measurement and model approaches, an enhancement across UK complex terrain in the range of a factor of 1.4–2.5 (i.e. 40–150% larger than current estimates) is likely over complex upland terrain. If at the upper limits of this, then significantly more ecosystems in the UK would be at a direct risk of degradation, and the potential for long-term non-remediable water quality issues increased

The spatial and temporal variation of water quality at a community garden site in an urban setting: citizen science in action

Interest in urban agriculture has increased rapidly in recent decades, but little is known about the effect of potential contaminants, such as groundwater pollution, in urban areas. Furthermore, local and timely science necessary for developing place-based solutions and management plans are lacking. We present a citizen-science-driven case study of water quality in a large urban community garden in southwestern London that was initiated in response to the concerns of members about the effect of inorganic compounds in the water supply on organic produce. The 5.6-ha community garden has been cultivated for fruit and vegetables since 1921 and hand-pumped boreholes drawing water from an underlying shallow aquifer provide the only source of irrigation. We assessed the spatial and temporal distributions of specific conductance and tryptophan-like fluorescence to explore the dynamics of inorganic and organic pollution based on water drawn from the boreholes. A trained citizen scientist made measurements with a calibrated Manta II probe over a 28-mo period from 2014 to 2016. We also surveyed >80 members of the community garden to gain insight into cultivation practices. Results indicate that the concerns about external sources of pollution were unfounded. We found little evidence of the effect of potential adjacent sources of contamination or of changes in water quality in time. Distinct trends were absent, and evidence of poorer water quality close to possible sources of urban contamination was not apparent. However, significant interborehole variations in water quality were directly associated with the storage and use of manure on the site and local geological conditions. The study demonstrates the potential of citizen science to respond to community concerns and generate new and novel information when participants are engaged, trained, and equipped over longer periods of time

Historic droughts inventory of references from British tabloid newspapers 1992-2014

Mentions of the word drought* in articles published by British tabloids newspapers between 1992-2014. The asterisk (*) is a wildcard to indicate that the search considered different forms of the search term: drought, droughts, hyphenated words (e.g. drought-resistant), or adjectival occurrences (droughty). The following newspapers are included, in their weekday or Sunday publications: The Daily Mail, The Daily Record, The Daily Mirror, The Sun, The Express, The Daily Star. Historic Droughts was a four year (2014 – 2018), £1.5m project funded by the UK Research Councils, aiming to develop a cross-disciplinary understanding of past drought episodes that have affected the United Kingdom (UK), with a view to developing improved tools for managing droughts in future. Drought and water scarcity (DWS) events are significant threats to livelihoods and wellbeing in many countries, including the United Kingdom (UK). Parts of the UK are already water-stressed and are facing a wide range of pressures, including an expanding population and intensifying exploitation of increasingly limited water resources. In addition, many regions may become significantly drier in future due to environmental changes, all of which implies major challenges to water resource management. However, DWS events are not simply natural hazards. There are also a range of socio-economic and regulatory factors that may influence the course of droughts, such as water consumption practices and abstraction licensing regimes. Consequently, if DWS events are to be better managed, there is a need for a more detailed understanding of the links between hydrometeorological and social systems during droughts. With this research gap in mind, the Historic Droughts project aimed to develop an interdisciplinary understanding of drought from a range of different perspectives. Based on an analysis of information from a wide range of sectors (hydrometeorological, environmental, agricultural, regulatory, social and cultural), the project characterised and quantified the history of drought and water scarcity events since the late 19th century. The Historic Droughts project involved eight institutions across the UK: the British Geological Survey the Centre for Ecology & Hydrology, Cranfield University, the University of Exeter, HR Wallingford, Lancaster University, the Met Office, and the University of Oxford. </p

Historic droughts inventory of references from British broadsheet newspapers 1990-2014

Mentions of the word "drought"* in articles published by British broadsheet newspapers between 1990-2014. The asterisk (*) is a wildcard to indicate that the search considered different forms of the search term: drought, droughts, hyphenated words (e.g. drought-resistant), or adjectival occurrences (droughty). The following newspapers are included, in their weekday or Sunday publications: The Times, The Daily Telegraph, The Guardian/The Observer, The Independent, The Herald, The Scotsman. Historic Droughts was a four year (2014 – 2018), £1.5m project funded by the UK Research Councils, aiming to develop a cross-disciplinary understanding of past drought episodes that have affected the United Kingdom (UK), with a view to developing improved tools for managing droughts in future. Drought and water scarcity (DWS) events are significant threats to livelihoods and wellbeing in many countries, including the United Kingdom (UK). Parts of the UK are already water-stressed and are facing a wide range of pressures, including an expanding population and intensifying exploitation of increasingly limited water resources. In addition, many regions may become significantly drier in future due to environmental changes, all of which implies major challenges to water resource management. However, DWS events are not simply natural hazards. There are also a range of socio-economic and regulatory factors that may influence the course of droughts, such as water consumption practices and abstraction licensing regimes. Consequently, if DWS events are to be better managed, there is a need for a more detailed understanding of the links between hydrometeorological and social systems during droughts. With this research gap in mind, the Historic Droughts project aimed to develop an interdisciplinary understanding of drought from a range of different perspectives. Based on an analysis of information from a wide range of sectors (hydrometeorological, environmental, agricultural, regulatory, social and cultural), the project characterised and quantified the history of drought and water scarcity events since the late 19th century. The Historic Droughts project involved eight institutions across the UK: the British Geological Survey the Centre for Ecology & Hydrology, Cranfield University, the University of Exeter, HR Wallingford, Lancaster University, the Met Office, and the University of Oxford. </p

Historic droughts inventory of references from British twentieth-century newspapers 1900-1999

Occurrences of the search term 'drought' in articles published in editions of The Times between 1900 and 1999, with surrounding context of 10 words on each side of the search term. The inventory provides information regarding publication date and instances of place-names within the UK that co-occur with the search term. Historic Droughts was a four year (2014 – 2018), £1.5m project funded by the UK Research Councils, aiming to develop a cross-disciplinary understanding of past drought episodes that have affected the United Kingdom (UK), with a view to developing improved tools for managing droughts in future. Drought and water scarcity (DWS) events are significant threats to livelihoods and wellbeing in many countries, including the United Kingdom (UK). Parts of the UK are already water-stressed and are facing a wide range of pressures, including an expanding population and intensifying exploitation of increasingly limited water resources. In addition, many regions may become significantly drier in future due to environmental changes, all of which implies major challenges to water resource management. However, DWS events are not simply natural hazards. There are also a range of socio-economic and regulatory factors that may influence the course of droughts, such as water consumption practices and abstraction licensing regimes. Consequently, if DWS events are to be better managed, there is a need for a more detailed understanding of the links between hydrometeorological and social systems during droughts. With this research gap in mind, the Historic Droughts project aimed to develop an interdisciplinary understanding of drought from a range of different perspectives. Based on an analysis of information from a wide range of sectors (hydrometeorological, environmental, agricultural, regulatory, social and cultural), the project characterised and quantified the history of drought and water scarcity events since the late 19th century. The Historic Droughts project involved eight institutions across the UK: the British Geological Survey the Centre for Ecology & Hydrology, Cranfield University, the University of Exeter, HR Wallingford, Lancaster University, the Met Office, and the University of Oxford. </p

Historic droughts inventory of references from British nineteenth-century newspapers 1800-1900

Occurrences of the search term 'drought' in articles published by nine British regional and national newspapers between 1800 and 1900, with surrounding context of 10 words on each side of the search term. The following newspapers were considered: The Era; Glasgow Herald; Hampshire and Portsmouth Telegraph; Ipswich Journal; Northern Echo; Pall Mall Gazette; Reynold’s Journal; Western Mail; and The Times. None of the individual newspapers cover this entire period; a number of titles were established part way through the nineteenth century and some have missing years. The publication dates and any missing years are detailed in the supporting information. The inventory provides information regarding publication date and instances of place-names within the UK that co-occur with the search term. Historic Droughts was a four year (2014 – 2018), £1.5m project funded by the UK Research Councils, aiming to develop a cross-disciplinary understanding of past drought episodes that have affected the United Kingdom (UK), with a view to developing improved tools for managing droughts in future. Drought and water scarcity (DWS) events are significant threats to livelihoods and wellbeing in many countries, including the United Kingdom (UK). Parts of the UK are already water-stressed and are facing a wide range of pressures, including an expanding population and intensifying exploitation of increasingly limited water resources. In addition, many regions may become significantly drier in future due to environmental changes, all of which implies major challenges to water resource management. However, DWS events are not simply natural hazards. There are also a range of socio-economic and regulatory factors that may influence the course of droughts, such as water consumption practices and abstraction licensing regimes. Consequently, if DWS events are to be better managed, there is a need for a more detailed understanding of the links between hydrometeorological and social systems during droughts. With this research gap in mind, the Historic Droughts project aimed to develop an interdisciplinary understanding of drought from a range of different perspectives. Based on an analysis of information from a wide range of sectors (hydrometeorological, environmental, agricultural, regulatory, social and cultural), the project characterised and quantified the history of drought and water scarcity events since the late 19th century. The Historic Droughts project involved eight institutions across the UK: the British Geological Survey the Centre for Ecology & Hydrology, Cranfield University, the University of Exeter, HR Wallingford, Lancaster University, the Met Office, and the University of Oxford.</p

Review of methods for assessing deposition of reactive nitrogen pollutants across complex terrain with focus on the UK

This is the final version. Available on open access from the Royal Society of Chemistry via the DOI in this recordThis review is a summary of the most up-to-date knowledge regarding assessment of atmospheric deposition of reactive nitrogen (Nr) pollutants across complex terrain in the UK. Progress in the understanding of the mechanisms and quantification of Nr deposition in areas of complex topography is slow, as no concerted attempts to measure the components of Nr in complex terrain have been made in the last decade. This is likely due to the inherent complexity of the atmospheric processes and chemical interactions which contribute to deposition in these areas. More than 300 studies have been reviewed, and we have consulted with a panel of international experts which we assembled for that purpose. We report here on key findings and knowledge gaps identified regarding measurement and modelling techniques used to quantify deposition of Nr across complex terrain in the UK, which depending on definition, may represent up to 60% of land coverage across Great Britain. The large body of peer reviewed papers, reports and other items reviewed in this study has highlighted both the strengths and weaknesses in the tools available to scientists, regulators and policy makers. This review highlights that there is no coherent global research effort to constrain the uncertainties in Nr deposition over complex terrain, despite the clearly identified risk of N deposition to ecosystems and water quality. All evidence identified that enhanced Nr deposition across complex terrain occurs, and magnitude of the enhancement is not known; however, there are major uncertainties particularly in the differences between modelled and measured wet deposition in complex terrain and representing accurate surface interactions in models. Using simplified estimates for Nr deposition, based on current understanding of current measurement and model approaches, an enhancement across UK complex terrain in the range of a factor of 1.4-2.5 (i.e. 40-150% larger than current estimates) is likely over complex upland terrain. If at the upper limits of this, then significantly more ecosystems in the UK would be at a direct risk of degradation, and the potential for long-term non-remediable water quality issues increased.UK Department for Environment, Food and Rural Affairs (DEFRA)Environment Agency (EA)Natural Environment Research Council (NERC