Long‐term environmental monitoring in the UK: origins and achievements of the Plynlimon catchment study

Abstract

The Plynlimon catchments are the UK's most intensively studied long-term research basins, with 40 years of hydrological and hydrochemical observations. Used to study the impacts of land cover, their establishment, progress and achievements is a complex story of scientific advances in response to national needs, set against a background of academic controversy and competing stakeholder pressures, that remains relevant today. Established to answer the important practical question 'Do forests use more water than grassland in our climate?', these research basins helped to revolutionise our fundamental understanding of forest hydrology in Britain, and became a multi-disciplinary 'outdoor laboratory' encompassing floods and droughts, acidification and water chemistry, process studies and climate change used by many universities and research organisations. The findings of the studies there have been widely published, with over 500 papers in refereed journals, and the measurements shared with the international research community. Nevertheless, many data users remain unaware of how and why the catchments were established, the challenges that were overcome, and the ways in which the research programme evolved to meet changing needs. As the study enters its fifth decade, this paper takes the opportunity to look back at its establishment, assess the outputs and offer guidance to other researchers wishing to embark on new catchment or observatory studies.

The relative role of soil type and tree cover on water storage and transmission in northern headwater catchments

“…Correspondingly, total dynamic storage changes for the upper 0.6 m soil profile under tree cover (220 mm) were more than double those under heather (105 mm). It is now accepted that in the UK uplands, the main differences in evapotranspiration between trees and heather are the result of higher interception and higher aerodynamic roughness of forest compared with shorter vegetation (Calder, ; Robinson et al ., ). Overall, the dynamic storage variations for the forest cover soil were ~25% of the long‐term average annual precipitation.…”

Comparison of saturated areas mapping methods in the Jizera Mountains, Czech Republic

“…The paper by Robinson et al (2013), written to commemorate the 40 years of the Plynlimon in Wales, not only goes through the important scientific results (e.g. Blackie and Robinson, 2007;Brandt et al, 2004;Calder, 1977;Kirby et al, 1991;Marc and Robinson, 2007;Robinson and Dupeyrat, 2005) but also describes the academic controversy and stakeholder pressures which brought about the existence of the catchments.…”

The Hydrological Open Air Laboratory (HOAL) in Petzenkirchen: a hypothesis-driven observatory

“…Such measurements will also allow shedding of light on microbial transport processes at the catchment scale. While automated measuring devices have already been tested for groundwater (Ryzinska-Paier et al, 2014), so far no evaluation exists for surface water. Surface water may involve additional challenges due to higher sediment concentrations and bacterial contamination levels which may contaminate or block inlet pipes and other system components.…”

“…One such collaboration is with the Microtronics company regarding telemetering data from the catchment to the central server and data management. Another is with the VWM (Vienna Water Monitoring) company regarding testing novel devices for automated measurements of a proxy parameter of microbial faecal pollution in the stream of the HOAL under field conditions (Farnleitner et al, 2002;Ryzinska-Paier et al, 2014).…”

“…Some corner stones include the Coweeta hydrologic laboratory (Southern Appalachians) in the early 1930s where the focus was on forest management practices (Swank and Crossley, 1988;Elliott and Vose, 2011), the Plynlimon catchment (Wales) in the late 1960s where pollution was the main interest (Kirby et al, 1991;Robinson et al, 2013), the Weiherbach (Germany) and Löhnersbach (Austria) catchments in the 1990s where a broader, interdisciplinary approach was taken (Plate and Zehe, 2008;Zehe et al, 2001;Kirnbauer et al, 2005); and the Tarrawarra catchment (Australia) in the 1990s where the focus was specifically on spatial process patterns (Western et al, , 1999(Western et al, , 2001). An overview of some of the European experimental catchments is given in Schumann et al (2010) and Holko et al (2015).…”