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53. Assessing the distribution pattern of otters in four rivers of the Indian Himalayan biodiversity hotspot

Author

Everard, Mark, Gupta, Nishikant, Tiwari, Varun, Savage, Melissa, Hussain, Syed Ainul, Chadwick, Michael A., Johnson, Jeyaraj Antony, Nawab, Asghar, and Belwal, Vinod K.

Subjects
Agricultural and Veterinary Sciences, Life on Land, human-induced stressors, climate change, freshwater, human-induced stressors, Lutrinae, Mustelidae, otters, Uttarakhand, wetlands, Biological Sciences, wetlands, Marine Biology & Hydrobiology, climate change, Affordable and Clean Energy, Lutrinae, Uttarakhand, Mustelidae, otters, freshwater, Environmental Sciences
Abstract

1.The Eurasian otter (Lutra lutra), Smooth-coated otter (Lutrogale perspicillata) and Asian small-clawed otter (Aonyx cinereus) have all been previously reported from the Indian state of Uttarakhand. However, little information is available about these species’ current distribution in a mountainous region that is subject to increasing human-induced stressors (e.g. hydropower plants, pollution, sand and boulder mining, destructive fishing techniques, poaching). 2.Due to the important role of these otters in structuring riverine food webs (particularly taking account of their roles as top carnivores), it is critical that these animals receive suitable protection in the face of a projected rise in temperature, change in precipitation patterns, and associated river flows in this Himalayan biodiversity hotspot. This study assesses otter distribution in four rivers of Uttarakhand, as a basis for informing future conservation actions.3.Field surveys were conducted (October 2018 – January 2019) in four Himalayan rivers (reaches of the Kosi, Ramganga, Khoh and Song Rivers), supported by semi-structured interviews (N=379) conducted with members of local communities to ascertain qualitative data on views and perceptions of otter species. In addition, community-based otter awareness camps were organized for local youths (N=105), adults (N=115) and school children (N=256 covering 10 schools). Habitat suitability maps were created using remote sensing data, survey findings and a Geographic Information System (GIS) to provide information about priority river reaches to be targeted for future conservation efforts. 4.This study provides critical interdisciplinary baseline information to guide decision-makers towards developing a targeted, otter-specific conservation program for this important Himalayan biodiversity hotspot. The otter conservation education programs conducted during this study resulted in a proposal to set up a community-based conservation initiative (CBCI) to monitor and report otter sightings from the area, potentially representing a way forward for achieving simultaneous otter conservation and associated ecosystem benefits for local communities.

Published
2020

61. Low-cost electronic sensors for environmental research: Pitfalls and opportunities

Author

Chan, Kristofer, primary, Schillereff, Daniel N, additional, Baas, Andreas CW, additional, Chadwick, Michael A, additional, Main, Bruce, additional, Mulligan, Mark, additional, O’Shea, Francis T, additional, Pearce, Reagan, additional, Smith, Thomas EL, additional, van Soesbergen, Arnout, additional, Tebbs, Emma, additional, and Thompson, Joseph, additional

Published
2020
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67. Influence of urban river restoration on nitrogen dynamics at the sediment-water interface

Author

Lavelle, Anna M., Bury, Nic R., O’Shea, Francis T., and Chadwick, Michael A.

Subjects
inorganic chemicals, Geologic Sediments, Nitrogen, Science, Marine and Aquatic Sciences, Water Columns, Oceanography, Urban Environments, Rivers, Surface Water, Ammonium Compounds, Urban Ecology, Ecosystem, Petrology, Sedimentary Geology, Nitrates, Ecology, Ecology and Environmental Sciences, Water Pollution, Aquatic Environments, Biology and Life Sciences, Water, food and beverages, Geology, Bodies of Water, Biogeochemistry, Eutrophication, Terrestrial Environments, Pollution, Chemistry, Geochemistry, Physical Sciences, Earth Sciences, Medicine, Sediment, Hydrology, Water Pollutants, Chemical, Research Article, Freshwater Environments
Abstract

River restoration projects focused on increasing flow heterogeneity and channel biodiversity through use of in-channel structures can facilitate ecosystem services which promote nitrogen (N) storage and reduce eutrophication, essential aspects of N dynamics in streams. In this study we use small flux chambers to examine ammonium (NH4+) and nitrate (NO3-) cycling across the sediment-water interface. Paired restored and unrestored study sites in 5 urban tributaries of the River Thames in Greater London were used to examine N dynamics following physical disturbances (0-3 min exposures) and subsequent biogeochemical activity (3-10 min exposures). Average ambient NH4+ concentrations ranged from 28.0 to 731.7 μg l-1 among all sites, with the highest concentrations occurring at restored sites overall. Average NO3- concentrations ranged from 9.6 to 26.4 mg l-1 but did not differ between restored and unrestored sites (p=0.10). Average NH4+ fluxes at restored sites ranged from -11.5 to 6.5 μg m-2 sec-1, however restoration did not significantly influence NH4+ uptake or regeneration rates between 0-3 minutes and 3-10 minutes. However average NO3- uptake fluxes among sites responded significantly to physical disturbances ranging from -148.8 to 432.6 μg m-2 sec-1. Neither NH4+ nor NO3- fluxes were significantly correlated with chlorophyll-a (Chl-a), total organic matter (TOM) or sediment grain size. We attributed variations in overall N fluxes to N-specific sediment storage capacity, biogeochemical transformations and potential legacy effects associated with urban pollution. It is clear that a greater understanding of mechanisms driving the dynamic transfer, processing, and removal of NH4+ and NO3- in urban river systems is required for informing future river restoration strategies.

Published
2019

68. Addressing the Arsenic Issue in the Lower Mekong Region—The Challenges and Systematic Approaches

Author

Hristovski Kiril, Henderson Mark, Leslie Greg, Mirumachi Naho, Chadwick Michael, Rosl Sh-Refaat, and Markovski Jasmina

Subjects
Humanitarian engineering, business.industry, Multidisciplinary approach, Corporate governance, Water storage, Sustainability, Water quality, business, Training (civil), Environmental planning, Hydropower
Abstract

Construction of dams in the upper catchments of the Mekong river for hydropower generation and water storage threatens to alter the relative allocation of surface water resources raising concerns about increased reliance on groundwater withdrawals for irrigation and drinking water purposes. These alterations to water regime of the Mekong create groundwater management implications related to arsenic and other water quality challenges, which are catalyzed by the proliferation of tube wells as an alternative solution for access to potable water. In an attempt to address this newly developed paradigm and develop a systematic approach for sustainable potable water solutions in the lower Mekong region, the goal of this introspect is to identify and elucidate the factors that govern the existing challenges and issues related to the arsenic problem in this densely populated region. Specifically, this introspect examines four key areas: (1) water governance and hydrogeology; (2) arsenic mobilization, metal toxicity, and nutrition; (3) public health and epidemiology; and (4) humanitarian engineering and water treatment, as cornerstones of a sustainable platform for mitigating the arsenic problem in the lower Mekong region. This sustainable arsenic management platform could only be implemented through synchronized engagement of multidisciplinary teams. Establishing an effective educational and training platform represents a prerequisite for developing and implementing a long-term system-based platform for sustainably managing the arsenic problem in the lower Mekong area. The universities in the developed countries are uniquely positioned on many levels to lead the creation of this platform because they have the institutional and intellectual capacity to establish interdisciplinary research and educational collaborations with the universities, communities, organizations, and institutions in the lower Mekong region. Only through joint efforts the arsenic issue in the lower Mekong region could be successfully addressed.

Published
2019

71. Prospects for the joint implementation of sulphur emission reductions in Europe

Author

Bailey, Peter D., Gough, Clair A., Millock, Katrin, and Chadwick, Michael J.

Subjects
Europe -- Environmental policy, Environmental law -- Evaluation, Business, Environmental issues, Petroleum, energy and mining industries
Abstract

Signatory countries to the 1994 Oslo Protocol on Further Reductions of Sulphur Emissions may find it easier to meet their obligations under the treaty if they put in place a joint implementation system for sulphur emission reduction. Such a system would take into account the spatial dimension that characterizes sulphur pollution in Europe. However, the chances of such a system being put in place are virtually nil due to the difficulties of incorporating such a spatial dimension into it.

Published
1996

73. Low-cost electronic sensors for environmental research: Pitfalls and opportunities.

Author

Chan, Kristofer, Schillereff, Daniel N, Baas, Andreas CW, Chadwick, Michael A, Main, Bruce, Mulligan, Mark, O'Shea, Francis T, Pearce, Reagan, Smith, Thomas EL, van Soesbergen, Arnout, Tebbs, Emma, and Thompson, Joseph

Subjects
SENSOR networks, DETECTORS, MAKER movement, ENVIRONMENTAL monitoring, LAKE sediments, ENVIRONMENTAL sciences, AIR quality monitoring
Abstract

Repeat observations underpin our understanding of environmental processes, but financial constraints often limit scientists' ability to deploy dense networks of conventional commercial instrumentation. Rapid growth in the Internet-Of-Things (IoT) and the maker movement is paving the way for low-cost electronic sensors to transform global environmental monitoring. Accessible and inexpensive sensor construction is also fostering exciting opportunities for citizen science and participatory research. Drawing on 6 years of developmental work with Arduino-based open-source hardware and software, extensive laboratory and field testing, and incorporation of such technology into active research programmes, we outline a series of successes, failures and lessons learned in designing and deploying environmental sensors. Six case studies are presented: a water table depth probe, air and water quality sensors, multi-parameter weather stations, a time-sequencing lake sediment trap, and a sonic anemometer for monitoring sand transport. Schematics, code and purchasing guidance to reproduce our sensors are described in the paper, with detailed build instructions hosted on our King's College London Geography Environmental Sensors Github repository and the FreeStation project website. We show in each case study that manual design and construction can produce research-grade scientific instrumentation (mean bias error for calibrated sensors –0.04 to 23%) for a fraction of the conventional cost, provided rigorous, sensor-specific calibration and field testing is conducted. In sharing our collective experiences with build-it-yourself environmental monitoring, we intend for this paper to act as a catalyst for physical geographers and the wider environmental science community to begin incorporating low-cost sensor development into their research activities. The capacity to deploy denser sensor networks should ultimately lead to superior environmental monitoring at the local to global scales. [ABSTRACT FROM AUTHOR]

Published
2021
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75. A double-blind amino acids, L-tryptophan and L-tyrosine, and placebo study with cocaine-dependent subjects in an inpatient chemical dependency treatment center

Author

Chadwick, Michael J., Gregory, David L., and Wendling, Glenda

Subjects
Tryptophan -- Health aspects, Cocaine -- Physiological aspects, Tyrosine -- Health aspects, Cocaine abuse -- Care and treatment, Drug withdrawal symptoms -- Care and treatment, Health, Psychology and mental health
Abstract

Cocaine addiction has reached epidemic proportions, with serious consequences for users and society as a whole. Cocaine stimulates pleasure centers in the brain by causing neurotransmitters (brain chemicals) to flood the brain and by preventing their re-uptake, so that they remain in the brain for longer than normal. When neurotransmitter levels drop, cocaine users experience cravings for the drug and withdrawal symptoms, which interferes with efforts to treat the addiction. Since neurotransmitters are manufactured by the body from amino acids, it was suggested that treatment with certain amino acids might alleviate or reduce withdrawal symptoms. Two amino acids, L-tryptophan and L-tyrosine, were given to 29 people undergoing inpatient medical treatment for cocaine addiction. The subjects were randomly assigned to receive either the amino acid supplements or a placebo for 14 days. The groups then switched so that they received the opposite treatment; neither the staff nor the patients knew which they were receiving. Both patients and staff recorded the patients' withdrawal symptoms (such as anxiety, irritability, paranoia, nausea, and headache) throughout the period. The results showed that the amino acid supplements did not significantly reduce cravings for cocaine or any major withdrawal symptoms. It is possible that different doses or the timing of amino acid treatment might yield different results. (Consumer Summary produced by Reliance Medical Information, Inc.), INTRODUCTION Cocaine use has been documented as early as 1700 A.D. by the natives of the Andes. Sigmung Freud wrote a famous paper, 'On Coca,' in 1884 encouraging its use [...]

Published
1990

77. Variability of UK seagrass sediment carbon: Implications for blue carbon estimates and marine conservation management

Author

Green, Alix, Chadwick, Michael A., and Jones, Peter J. S.

Subjects
Topography, Atmospheric Science, Carbon Sequestration, Conservation of Natural Resources, Geologic Sediments, Environmental Engineering, Oceans and Seas, Marine and Aquatic Sciences, lcsh:Medicine, Marine Biology, Ecosystems, Marine Conservation, Greenhouse Gases, Environmental Chemistry, lcsh:Science, Petrology, Conservation Science, Sedimentary Geology, Islands, Landforms, Ecology, Zosteraceae, Ecology and Environmental Sciences, lcsh:R, Chemical Compounds, Biology and Life Sciences, Geology, Geomorphology, Carbon Dioxide, Carbon, United Kingdom, Habitats, Chemistry, Models, Economic, Atmospheric Chemistry, Physical Sciences, Earth Sciences, Engineering and Technology, Sediment, lcsh:Q, Research Article
Abstract

Seagrass meadows provide a multitude of ecosystem services, including a capacity to sequester carbon dioxide (CO2) within their sediments. Seagrass research in the UK is lacking and there is no published data on sediment carbon (C) within UK seagrass meadows. We sampled 13 Zostera marina meadows along the southwest coast of the UK to assess the variability in their sedimentary organic carbon (OC) stocks. The study sites were considered representative of sub-tidal Z. marina meadows in the UK, spanning a gradient of sheltered to exposed sites, varying in formation, size and density, but found along the same latitudinal gradient. OC stocks (Cstocks) integrated across 100cm depth profiles were similar among all sites (98.01 ± 2.15 to 140.24 ± 10.27 Mg C ha-1), apart from at Drakes Island, which recorded an unusually high Cstock (380.07 ± 17.51 Mg C ha-1) compared to the rest of the region. The total standing stock of C in the top 100cm of the surveyed seagrass meadows was 66,337 t C, or the equivalent of 10,512 individual UK people's CO2 emissions per year. This figure is particularly significant relative to the seagrass area, which totalled 549.79 ha. Using estimates of seagrass cover throughout the UK and recent UK C trading values we approximate that the monetary value of the UK's seagrass standing C stock is between £2.6 million and £5.3 million. The C stock of the UK's seagrass meadows represent one of the largest documented C stocks within Europe and are, therefore, of important ecosystem service value. The research raises questions concerning the reliability of using global or regional data as a proxy for local seagrass C stock estimates and adds to a growing body of literature that is looking to understand the mechanisms of seagrass C storage. When taken with the fact that seagrass meadows are an important habitat for commercially important and endangered species in the UK, along with their declining health and cover, this research supports the need for more robust conservation strategies for UK seagrass habitats.

Published
2018

79. Effectiveness of a national quality improvement programme to improve survival after emergency abdominal surgery (EPOCH): a stepped-wedge cluster-randomised trial

Author

Peden, Carol J, primary, Stephens, Tim, additional, Martin, Graham, additional, Kahan, Brennan C, additional, Thomson, Ann, additional, Rivett, Kate, additional, Wells, Duncan, additional, Richardson, Gerry, additional, Kerry, Sally, additional, Bion, Julian, additional, Pearse, Rupert M, additional, Pearse, Rupert, additional, Peden, Carol, additional, Kahan, Brennan, additional, Brett, Stephen, additional, Ackland, Gareth, additional, Grocott, Mike, additional, Holt, Peter, additional, Robert, Glenn, additional, Ukoumunne, Obioha, additional, Waring, Justin, additional, Everingham, Kirsty, additional, Phull, Mandeep, additional, Cromwell, David, additional, Evley, Rachel, additional, Lilford, Richard, additional, Kocman, David, additional, Asaria, Miqdad, additional, Tarrant, Carolyn, additional, Yang, Fan, additional, Abraham, Ajit, additional, Bothma, Pieter, additional, Conway, Daniel, additional, Stapleton, Clare, additional, Edwards, Mark, additional, Minto, Gary, additional, Saunders, David, additional, Owen, Tom, additional, Waldmann, Carl, additional, Hayden, Paul, additional, Gillies, Michael, additional, Tighe, Sean, additional, Smith, Neil, additional, Mythen, Monty, additional, Murray, David, additional, Lobo, Dileep, additional, Leuwer, Martin, additional, Kirk-Bayley, Justin, additional, Howell, Simon, additional, Gordon, Anthony, additional, Anderson, Iain, additional, Lourtie, Jose, additional, Walker, Simon, additional, Drake, Sharon, additional, Murray, Dave, additional, Watson, Nick, additional, Szakmany, Tamas, additional, Sutcliffe, Robert, additional, Mahajan, Ravi, additional, Girling, Alan, additional, Forbes, Gordon, additional, Faiz, Omar, additional, Blunt, Mark, additional, Singh, Surjait, additional, Steel, Alistair, additional, Wong, Kate, additional, Cabreros, Leilani, additional, Chitre, Vivek, additional, Obideyi, Ayodele, additional, Ali, Dhiraj, additional, Blenk, Karl, additional, Broad, Dan, additional, Brodbeck, Andreas, additional, Dumpala, Rajesh, additional, Engel, Arnth, additional, Ganepola, Ranjit, additional, Garg, Sudha, additional, Gay, Mike, additional, Karlikowsk, Michael, additional, Lams, Edward, additional, Millican, Dean, additional, Misane, Inga, additional, Mull, Ajaya, additional, Naik, Veena, additional, Pushpa, Nathan, additional, Nutt, Chris, additional, Sagadai, Saravanna, additional, Stuart, Hazel, additional, Noble, Paul, additional, Van De Velde, Niko, additional, Hudson, Liam, additional, Benlloch, Raoul, additional, Singh, Satish, additional, Verma, Karan, additional, Laba, Damian, additional, Carmichael, Jack, additional, Richardson, Peter, additional, Wilson, Graham, additional, Lewis, Ricky, additional, Surendran, Karthik, additional, El-Damatty, Essam, additional, Gurung, Sarada, additional, Raulusaite, Ilona, additional, Gerstina, Nabua, additional, Rochester, Chloe, additional, Kuldip, Rai, additional, Lindner, Andrew, additional, Murray, Therese, additional, Vivek, Chitre, additional, Lal, Roshan, additional, Downey, Sarah, additional, Velchuru, Vamsi, additional, Aryal, Kamal, additional, Guruswamy, Raman, additional, Shankar, Kirosh, additional, Porter, Helen, additional, Tutton, Matthew, additional, Agostini, Helen, additional, Fletcher, Simon, additional, Wharton, Richard, additional, Hutchinson, Steve, additional, Maiya, Bala, additional, Howard-Griffin, Richard, additional, Crabtree, Michael, additional, Kushakovsky, Vlad, additional, Omer, Abdel, additional, Nadarajavan, Senthil, additional, Bell, Stephanie, additional, Patil, Vishal, additional, Jah, Asif, additional, Mahroof, Razeen, additional, Watson, Nicholas, additional, Tansley, John, additional, Moncaster, Gareth, additional, Flint, Neil, additional, Miller, Andrew, additional, Wood, Marcus, additional, Prematie, Andreou, additional, Roth, Sally, additional, Bowery, Sarah, additional, Hales, Dawn, additional, Shah, Tanuja, additional, Tierney, Gill, additional, Morris, Craig, additional, Iftikhar, Syed, additional, Shukla, Amit, additional, O'Dwyer, Grainne, additional, Wolverson, Adam, additional, Adams, Ferdinand, additional, Perrin-Brown, Laura, additional, White, Tim, additional, Beavis, Sarah, additional, Banks, Victoria, additional, Abercrombie, John, additional, Mole, Jonathon, additional, Chana, Avninder, additional, Banerjea, Ayan, additional, Humes, David, additional, Dhingsa, Rajpal, additional, Wells, John, additional, Brown, Stephanie, additional, Adegoke, Kenneth, additional, Tofte, Barclay, additional, Alegria, Ana, additional, Natarajan, Nat, additional, Akhtar, Mansoor, additional, Doughan, Samer, additional, Mackinnon, John, additional, Aravind, Biju, additional, Cook, Esther, additional, Snazelle, Mark, additional, Gardner, Matt, additional, Baldwin, Lee, additional, Bailey, Simon, additional, Lawton, Greg, additional, Divekar, Nandita, additional, Kukreja, Neil, additional, Sange, Mansoor, additional, Watson, Mark, additional, Satisha, Mallikarjunappa, additional, Protopapas, Michael, additional, Belagodu, Zakaulla, additional, Sarfi, Shameem, additional, Raju, Pasupathy, additional, Stacey, Brenda, additional, Campbell-Smith, Tim, additional, Parrington, Simon, additional, Desikan, Somi, additional, Brennan, Andrew, additional, Griffith, John, additional, Fletcher, Steve, additional, Farrow, Catherine, additional, Prestwich, Stewart, additional, Graham, Laura, additional, Northey, Martin, additional, Gokhale, Jay, additional, Mosley, Frances, additional, Alexander, Peter, additional, Sharma, Abhiram, additional, Brady, Will, additional, Hopper, John, additional, Hill, Oliver, additional, Varma, Sandeep, additional, Macklin, Christopher, additional, Rose, Alastair, additional, Narula, Harjeet, additional, Buckley, Sarah, additional, Simeson, Karen, additional, Sim, Kevin, additional, Chadwick, Michael, additional, Kuduvalli, Preeti, additional, Dowling, Susan, additional, McCairn, Amanda, additional, Wilson, Lawrence, additional, Vimalchandran, Dale, additional, Jhamatt, Anita, additional, Robin, Nicole, additional, Monk, David, additional, Bottomley, David, additional, Zuzan, Oliver, additional, Welters, Ingeborg, additional, Ross-Anderson, Davina, additional, Knowles, Charles, additional, Bunker, Nick, additional, Hu, Ying, additional, Januszewska, Marta, additional, Bodger, Phoebe, additional, Niebrzegowska, Edyta, additional, Correia, Carmen, additional, Haslop, Richard, additional, Abbott, Tom, additional, Tanqueray, Tabitha, additional, Wijeykoon, Sanjay, additional, Jain, Susan, additional, Full, Jens, additional, Cuming, Tamzin, additional, Bailey, Flora, additional, Chatzimichail, Stelios, additional, Cunha, Pedro, additional, Rehman, Almas, additional, Mohanty, Manab, additional, Radford, Nicola, additional, Mohr, Otto, additional, Patel, Hitesh, additional, Mateo, Dolores, additional, Raj, Ashok, additional, Machesney, Michael, additional, Abdul, Nazar, additional, Jemmet, Kim, additional, Campbell, Marta, additional, Inglis, David, additional, Parker, Thomas, additional, Medici, Thomas, additional, Chan, Peter, additional, Borgeaud, Nathan, additional, Mukherjee, Dipankar, additional, Odejinmi, Oluremi, additional, Jovaisa, Tomas, additional, Harwood, Elizabeth, additional, Moonesinghe, Ramani, additional, Mccullough, Jonathan, additional, Modha, Jigna, additional, Patel, Sanjiv, additional, Limb, James, additional, Bengeri, Sheshagiri, additional, Rafi, Amir, additional, Hall, Elizabeth, additional, Brown, James, additional, Gibson, Bruce, additional, McNelis, Una, additional, Bradburn, Mike, additional, Lawson, Maria, additional, Pick, Sara, additional, Gaughan, Matthew, additional, Browell, David, additional, Linnett, Vanessa, additional, Ritzema, Jenny, additional, O'Loughlin, Paul, additional, Cope, Sean, additional, Corson, John, additional, Roy, Alistair, additional, Furneval, Julie, additional, Holtham, Anitha, additional, Noblett, Sophie, additional, Dawson, Chris, additional, McMenemie, Fiona, additional, Pulsa, Stefan, additional, Clement, Ian, additional, Calder, Verity, additional, Allen, Katherine, additional, Rimmer, Catherine, additional, Reed, Helen, additional, Boyd, Christine, additional, Monkhouse, Diane, additional, Davies, Peter, additional, Mullenheim, Jost, additional, Cirstea, Emanuel, additional, Cain, Martyn, additional, Baillie, Kirsty, additional, Bhowmick, Arnab, additional, Jovestani, Keiarash, additional, Mcmullan, Sean, additional, Durant, Emma, additional, Williams, Alexandra, additional, Doyle, Donna, additional, Cupitt, Jason, additional, Barker, Jonathon, additional, Harper, Nick, additional, Brennan, Emma, additional, Subar, Daren, additional, Shawcross, Robert, additional, Sebastian, Dominic, additional, Patel, Panna, additional, O'Connell, Gillian, additional, Karvonen, Jyrki, additional, Ishaan, Maitra, additional, Hool, Alison, additional, Burns, Karen, additional, Mcarthur, Carol, additional, Stergios, Tezas, additional, Gursevak, Singh, additional, Sonia, Makvana, additional, Pratt, Heather, additional, Lynne, Kaighan, additional, McAfee, Sean, additional, Lewis, Chris, additional, Khalaf, Wael, additional, Coldwell, Chris, additional, Bronder, Christine, additional, Wilkinson, Mark, additional, Davis, Emma, additional, Arnold, Glenn, additional, Ziprin, Paul, additional, Bartlett, Rachel, additional, Stotz, Martin, additional, D'souza, Rovan, additional, Pemberton, Phillippa, additional, Agarwal, Banwari, additional, Sugavanam, Anita, additional, Tan, Melanie, additional, Varcada, Massimo, additional, Lyness, Craig, additional, Thorniley, Andrew, additional, Prabhudesai, Ash, additional, Griffin, Ruth, additional, Vashisht, Shubha, additional, Harris, James, additional, Wakeford, Julie, additional, Vaganov, Sergei, additional, Mohsen, Yasser, additional, Myers, Alister, additional, Iqbal, Qamar, additional, Harris, Simon, additional, Ijaz, Sami, additional, Burrow, James, additional, Rubulotta, Francesca, additional, El-Masry, Nabil, additional, Stranix, Nicola, additional, Rope, Tamsin, additional, Liasis, Lampros, additional, Husain, Tariq, additional, Watfah, Josef, additional, Griffiths, Megan, additional, Warusavitarne, Janindra, additional, Cartwright, Charles, additional, Baxter, Linden, additional, Visavadia, Rakhee, additional, Sim, Malcolm, additional, Wilson, Chris, additional, Harrison, Paul, additional, Williams, Dewi, additional, Bews-Hair, Maria, additional, Wrathall, Wayne, additional, Jardine, Catherine, additional, Mclaren, Paul, additional, Dreyer, Fanus, additional, Collins, Paddy, additional, Edwards, Jennifer, additional, Moug, Susan, additional, Rooney, Kevin, additional, Mcilveen, Erin, additional, Henderson, Steven, additional, Graham, Linda, additional, Stark, Gail, additional, Taylor, Lynn, additional, Munro, Mark, additional, Stewart, Lynn, additional, Dickinson, Natalie, additional, Rooney, Laura, additional, Bailey, Lindsay, additional, Murray, Diane, additional, Geary, Tim, additional, Gibson, Simon, additional, Pow, Colin, additional, Tan, Kerwei, additional, Stevenson, Richard, additional, Harrison, Ewen, additional, Lamb, Peter, additional, Carey, Kate, additional, Fitton, Laura, additional, Cook, Fabian, additional, Schwarz, Magen, additional, Morrison, Alan, additional, Bryce, Gavin, additional, Razouk, Khaled, additional, Cain, Kathryn, additional, Kunst, Gudrun, additional, Papagrigoriadis, Savvas, additional, Hopkins, Phil, additional, Fawcet, Adrian, additional, O'Carroll-Kuehn, Britta, additional, Girgis, Amira, additional, Janokowski, Stas, additional, Farhat, Sami, additional, Vig, Stella, additional, Hadi, Nada, additional, Parsons, Anthony, additional, Cecconi, Maurizio, additional, Melville, David, additional, Hartopp, Richard, additional, Woods, Justin, additional, Karat, Isabella, additional, Gerrard, David, additional, Curtis, Edward, additional, Somasekar, Krishnamurthy, additional, Morgan-Jones, Tom, additional, Martin, Michael, additional, Henwood, Mark, additional, Milne, Gordon, additional, Sivasankaranand, Ajit, additional, Scott, Alexandra, additional, Escofet, Xavier, additional, Toth-Tarsoly, Piroska, additional, Al Shama, Majed, additional, Hilton, Valerie, additional, Davis, Huw, additional, Williams, Gail, additional, Harvard, Tim, additional, Fitzgerald, Peter, additional, Hurford, Dom, additional, Muthuswamy, Babu, additional, Williams, Gethin, additional, Parry Jones, Jack, additional, Mason, Nick, additional, Rajagopal, Ramesh, additional, Shenoy, Shrisha, additional, Khater, Magdy, additional, Morgan, Richard, additional, Makris, Nikolaos, additional, Hermandes, Anil, additional, White, Andrew, additional, Finch, Guy, additional, Outram, Matt, additional, Wilkinson, Jonny, additional, Spimpolo, Jennifer, additional, Shaw, Debbie, additional, Obichere, Marion, additional, Brescia, Giovanni, additional, Menezes, Flavia, additional, Stafford, Helena, additional, Watters, Malcolm, additional, Thorn, Chris, additional, Stone, Julian, additional, Andrews, Sam, additional, Lythell, Nicola, additional, Langton, Helen, additional, Baxter, Stephen, additional, Fernandes, Roy, additional, Sunthareswaran, Rame, additional, Ankers, Alastair, additional, Panikkar, Kumar, additional, Sleight, Simon, additional, Cornforth, Belinda, additional, Bell, Louise, additional, Dodd, Phil, additional, Welsh, Fenella, additional, Watson, Geoff, additional, Dorman, Frankie, additional, Nash, Guy, additional, Bromilow, James, additional, Haigh, Fran, additional, Pogson, David, additional, Mercer, Stuart, additional, Tucker, Vanessa, additional, Way, Carolyn, additional, Kirby-Bott, James, additional, McLachan, Jenny, additional, Chambers, Rob, additional, Craven, Rachael, additional, Blazeby, Jane, additional, Freshwater-Turner, Dan, additional, Burrows, Lorna, additional, Howes, Helen, additional, Christie, Iain, additional, Coleman, Mark, additional, Waddy, Sam, additional, Sanders, Grant, additional, Patrick, Abigail, additional, Pitman, Catherine, additional, Tyson, Susan, additional, Smith, Hannah, additional, Rousseau, Guy, additional, Cartmell, Mark, additional, Hanousek, Jan, additional, Hollister, Nigel, additional, Kightly, Lynsey, additional, Pulletz, Mark, additional, Talwar, Anjay, additional, Baker, Susie, additional, Thomas, Ruth, additional, Gibbs, Richard, additional, Noble, Hamish, additional, Silsby, Joseph, additional, Black, Helen, additional, Evans, Thomas, additional, DeBrunner, Robert, additional, Cook, Nicola, additional, Hodges, Stacy, additional, Stevens, Amanda, additional, Felipe, Rowena, additional, Paddle, Jonathan, additional, May, Denzil, additional, Pickford, Alison, additional, Riddington, Sid, additional, Tucker, Olga, additional, Smart, Simon, additional, Marwick, Jeremy, additional, Suggett, Nigel, additional, Griffiths, Ewen, additional, Riddington, David, additional, Gill, Kathryn, additional, Cruickshank, Neil, additional, Susarla, Jay, additional, Leno, Emma, additional, Colley, Julie, additional, Burtenshaw, Andrew, additional, Lake, Stephen, additional, Greenwood, Jamie, additional, Bhardwaj, Sian, additional, Thrush, Jessica, additional, Wollaston, Julie, additional, Sonksen, Julian, additional, Patel, Rajan, additional, Jennings, Adrian, additional, Stanley, David, additional, Wright, Jenny, additional, Horner, Chris, additional, Baig, Faisal, additional, Cooke, Katie, additional, Singh, Jagdeep, additional, Claxton, Andrew, additional, Mirza, Nazzia, additional, Hester, Simon, additional, Knight, Georgia, additional, Kumar, Peeyush, additional, Saran, Taj, additional, Marangoni, Gabriele, additional, Townsend, Roger, additional, Thacker, Andy, additional, Scase, Anne, additional, Sharma, Meghna, additional, and Hale, Beth, additional

Published
2019
Full Text
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81. Impact of invasive quagga mussel (Dreissena rostriformis bugensis, Bivalva:Dreissenidae) on the macroinvertebrate community structure of a UK river

Author

Mills, Daniel N., Chadwick, Michael A., and Francis, Robert A.

Subjects
animal structures, colonisation, fungi, Wraysbury River, community ordination
Abstract

The arrival of invasive quagga mussel (Dreissena rostriformis bugensis) to the UK necessitates rapid study to evaluate its impact on benthic community structure where colonisation has occurred. In the Wraysbury River (west London), impact on benthic invertebrate community structure by invasion of quagga mussel was measured by comparing a series of invaded and uninvaded study sites over an annual period of monthly sampling. It was apparent that despite quagga mussel consistently forming a large proportion of stream biomass in invaded sites, community taxon richness and composition did not vary significantly in comparison to uninvaded sites. Similarly, total community biomass and density when excluding quagga mussel was mostly homogeneous across the study reach, with the exception of one site with the highest quagga mussel biomass and density. If quagga mussel biomass and density increased over time to levels found at this site, more significant changes to native community structure might be expected. This study represents a first benchmark for understanding the progression and impacts of quagga mussel invasion in UK rivers and these results will be essential for comparison in evaluating future change and impacts.

Published
2017

82. A novel 'triple drawdown' method highlights deficiencies in invasive alien crayfish survey and control techniques.

Author

Chadwick, Daniel D. A., Pritchard, Eleri G., Bradley, Paul, Sayer, Carl D., Chadwick, Michael A., Eagle, Lawrence J. B., Axmacher, Jan C., and Hong, Sungwon

Subjects
CRAYFISH, BIOLOGICAL invasions, AQUATIC organisms, FRESHWATER habitats, PLANT invasions
Abstract

Freshwater crayfish can be successful invaders that threaten native biota and aquatic ecosystems in numerous countries worldwide. Nonetheless, the inability of conventional crayfish survey techniques like trapping and handsearching to yield quantitative population data has limited the understanding of crayfish invasion biology and associated ecological impacts.Here, we employed a novel 'triple drawdown' (TDD) method to sample invasive populations of signal crayfish Pacifastacus leniusculus in a headwater stream in Northern England. The method was compared with conventional techniques of trapping and handsearching.The TDD method proved to be an effective technique with high capture efficiency, reporting signal crayfish densities from 20.5 to 110.4 animals/m2 at our study sites. These numbers exceed any previous estimates for similar streams.The TDD showed the vast majority of individuals across all sites were juvenile or sub‐adult (<26 mm CL), with only 2.3% of the population large enough (≥35 mm CL) to be caught in standard traps.Synthesis and applications. The triple drawdown (TDD) method demonstrates strong inefficiencies and biases in conventional crayfish survey and management techniques. Trapping is not recommended for representative sampling or control of juvenile dominated populations. TDDs, which can be adapted and modified to operate in multiple habitat types and freshwater systems, generate robust quantitative data on invasive crayfish population demographics in situ. This can advance our understanding of the biology of an important invader of freshwater systems around the world. Obtaining this data prior and post‐intervention is fundamental to evaluate invasive crayfish management, and we recommend the TDD method to assess the effectiveness of future control measures. [ABSTRACT FROM AUTHOR]

Published
2021
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84. Fluvial biotopes influence macroinvertebrate biodiversity in South-East asian tropical streams

Author

Baker, Kate, Chadwick, Michael A., Kahar, Rafhiah, Sulaiman, Zohrah Haji, and Wahab, Rodzay A.

Subjects
Tropical streams, Macroinvertebrates, Palm oil plantations, Biotopes, Biodiversity
Abstract

Given the widespread degradation of aquatic systems caused by land-use changes associated with palm oil production in South-East Asia, it is imperative to identify and study the remaining undisturbed rivers and streams. Stream macroinvertebrates are reliable indicators of environmental health. Linking the community structure of these organisms to natural hydraulic and geomorphic conditions (categorized as biotopes) is vital for the conservation and restoration of streams. This study characterizes the effects of biotopes on macroinvertebrate community structure in three streams within Ulu Temburong National Park in northern Borneo. Biotopes within these streams were categorized as either bedrock (waterfalls and cascades) or mixed substrate (riffles and pools). In total, 119 taxa were collected from all sampled biotopes, but not all taxa were collected from each stream. Biotopes were statistically distinct in terms of taxonomic richness, but not mean individual density or average community biomass. There were differences in community structure between waterfalls, cascades, pools, and riffles. The survey suggests that pool and riffle biotopes were more vulnerable to scouring flows and had similar community structure, while waterfalls and cascades likely experienced lower sheer stress during floods and had similar macroinvertebrate communities. This study has found that classification and mapping of macroinvertebrates with biotope theory in pristine, tropical streams is a useful framework for simplifying the many linkages between ecology, geomorphology, and hydrology. These natural patterns increase our understanding of tropical streams and can be used to assess the impacts of forest degradation.

Published
2016

85. Development and early outcomes of the national training initiative for transanal total mesorectal excision in the UK.

Author

Francis, N., Penna, M., Carter, F., Mortensen, N. J., Hompes, R., Arnold, Steve, Bandyopadhyay, Dibyendu, Black, John, Campbell, Ken, Chadwick, Michael, Chase, Kendra, Chitsabesen, Praminthra, Coleman, Mark, Dalton, Stephen, Doeve, Jaap, Hendrickse, Charles, Katory, Mark, Knol, Joep, Lee, Lian, and McArthur, David

Subjects
INTESTINAL perforation, TRADE associations, WOUNDS & injuries, SURGEONS, RECTAL cancer
Abstract

Aim: Transanal total mesorectal excision (TaTME) has attracted substantial interest amongst colorectal surgeons but its technical challenges may underlie the early reports of visceral injuries and oncological concerns. The aim of this study was to report on the feasibility, development and the outcome of the national pilot training initiative for TaTME‐UK. Methods: TaTME‐UK was successfully launched in September 2017 in partnership with the healthcare industry and endorsed by the Association of Coloproctology of Great Britain and Ireland. This multi‐modal training curriculum consisted of three phases: (i) set‐up; (ii) selection of pilot sites; and (iii) formal proctorship programme. Bespoke Global Assessment Scoring (GAS) forms were designed and completed by both trainees and mentors. Data were collected on patient demographics, tumour characteristics and perioperative clinical and histological outcomes. Results: Twenty‐four proctored cases were performed by 10 colorectal surgeons from five selected pilot sites. Median operative time was 331 ± 90 (195–610) min which was reduced to 283 ± 62 (195–340) min in the final case. Independent performance (GAS score of 5) was achieved for most operative steps by case 5. There was one conversion (4.2%), but no visceral injuries. Pathological data confirmed no bowel perforation and intact quality of the mesorectal TME specimens with clear distal margin in all cases and circumferential margins in 23/24 cases (96%). Conclusion: This exploratory study demonstrates acceptable early outcomes in a small cohort suggesting that a competency‐based multi‐modal training programme for TaTME can be feasible and safe to implement at a national level. [ABSTRACT FROM AUTHOR]

Published
2020
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86. Satellite remote sensing reveals impacts from dam‐associated hydrological changes on chlorophyll‐a in the world's largest desert lake.

Author

Tebbs, Emma J., Avery, Sean T., and Chadwick, Michael A.

Subjects
REMOTE sensing, LAKES, WATER management, SATELLITE-based remote sensing, DESERTS, EARTH dams, DAM failures
Abstract

We present an approach that uses satellite products to derive models for predicting lake chlorophyll from environmental variables, and for investigating impacts of changing environmental flows. Lake Turkana, Kenya, is the world's largest desert lake, and environmental flows from the Omo River have been modified since 2015 by the Gibe III dam in Ethiopia. Using satellite remote sensing, we have evaluated the influence of these altered hydrological patterns on large‐scale lake phytoplankton concentrations for the first time. Prior to dam completion, strong seasonal cycles and large spatial gradients in chlorophyll have been observed, related to natural fluctuations in the Omo River's seasonal discharge. During this period, mean lake chlorophyll showed a strong relationship with both river inflows and lake levels. Empirical models were derived which considered multiple hydro‐climatic drivers, but the best model for predicting chlorophyll‐a was a simple model based on Omo River discharge. Application of this model to data for 2015–2016 estimated that during the filling of Gibe III annual mean Lake Turkana chlorophyll declined by 30%. Future water management scenarios based on Gibe III operations predict reduced seasonal chlorophyll‐a variability, while irrigation scenarios showed marked declines in chlorophyll‐a depending on the level of abstraction. These changes demonstrate how infrastructure developments such as dams can significantly alter lake primary production. Our remote sensing approach is easy to adapt to other lakes to understand how their phytoplankton dynamics may be affected by water management scenarios. [ABSTRACT FROM AUTHOR]

Published
2020
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88. Eco-hydromorphic Classification for Understanding Stream Macroinvertebrate Biodiversity in Brunei Darussalam, Northern Borneo

Author

Baker, Kate, Chadwick, Michael, and Haji Sulaiman, Zohrah

Subjects
Tropical streams, Macroinvertebrates, biotopes, ecohydrogeomorphology, Biodiversity
Abstract

Linking ecology with river geomorphology and hydrology (geomorphic and hydraulic template) plays an important role in the study of macroinvertebrate biodiversity. This understanding and knowledge is crucial in implementing sensible conservation management for ecosystem health monitoring. However, most macroinvertebrate research has been conducted in temperate ecosystems. This study examines the eco-hydrogeomorphology and macroinvertebrate biodiversity of two remote tropical streams in northern Borneo (Bukit Pagon catchment, Brunei Darussalam’s highest mountain - 1850 m) using temperate classification models, more specifically, biotopes. Fast flowing biotopes were defined as bedrock runs and cobble riffles whilst the slow flowing biotopes were deposition pools. Macroinvertebrate size structure associated with biotopes, which can influence overall ecological processes, was also investigated. Forty-three macroinvertebrate taxa were recorded during the study; biodiversity was similar between the study streams. There were differences among biotopes with the lowest diversity occurring in fast flowing biotopes (p=0.05*). Community structure also varied among the biotopes. Cluster analysis of macroinvertebrate abundance revealed an 0.8 dissimilarity between the fast and slow biotopes. Several taxa were found in multiple biotopes, which is likely linked to the occurrence of moss and leaf litter. Macroinvertebrate size structure distribution between the fast and slow biotopes was statistically different. Our findings suggest biotopes may be an appropriate scale to investigate macroinvertebrate biodiversity in tropical streams. Specifically, we found that biotopes had different macroinvertebrate communities and richness. Further research is required to understand the importance of habitat parameters that are not directly related to flow velocities such as moss. These habitats are important as places of refuge, allowing colonisation that would otherwise be inhospitable during flood periods.

Published
2016

94. Artificial substrate experiments to investigate potential impacts of invasive quagga mussel (Dreissena rostriformis bugensis, Bivalvia: Dreissenidae) on macroinvertebrate communities in a UK river.

Author

Mills, Daniel N., Chadwick, Michael A., and Francis, Robert A.

Subjects
AQUATIC invertebrates, BIVALVES, MUSSELS, GAMMARUS pulex, AMPHIPODA, ANIMALS, FRESHWATER invertebrates, BIOLOGICAL invasions
Abstract

Predicting potential impacts of a new invasive species remains difficult. A group of particular concern in the UK are freshwater invertebrates from the Ponto-Caspian region, including the recently established quagga mussel (Dreissena rostriformis bugensis, Bivalvia: Dreissenidae). We explored invertebrate colonisation across a series of manipulated substrate tiles with gradated densities of D. r. bugensis shells fixed to their surface (2220, 1111, 666, 222 and 0 individuals m-2). Across three experiments of different substrate tile deployment duration (14, 30 and 62 days), we observed significant differences in invertebrate density and richness among shell density treatments. Variation was primarily driven by low and high values on our control and highest substrate shell treatments, respectively. Within each experiment, similar taxa appeared to benefit from the physical effects of D. r. bugensis shells (e.g. Gammarus pulex, Chironomidae spp., Elmidae spp. and Hydropsyche spp.) being found with greater abundance on substrate tiles with higher D. r. bugensis shell treatments. Compared to invertebrate density, the response of taxonomic richness was weaker and only significant within our 30 and 62 day experiments of longer substrate tile deployment duration. Regardless, increased invertebrate density and richness across the highest shell treatments provided a strong indication of potential D. r. bugensis impacts on macroinvertebrates in the study river. If mussel densities were to increase to equivalent levels in other UK rivers, we could expect similar impacts to benthic fauna. While the likelihood of D. r. bugensis achieving such population densities are uncertain in such environments, our results were considered conservative because they did not account for additional facilitative impacts associated with live mussels. We add that, in the context of invasive species management, potential facilitation of native benthic fauna associated with D. r. bugensis in the UK should not be considered positively, nor necessarily sustainable over longer time periods. Further, facilitative effects could assist the establishment of other invasive invertebrates such as amphipods of Dikerogammarus spp., which were first recorded in the study river during this investigation. [ABSTRACT FROM AUTHOR]

Published
2019
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