UV4Plants Workshop 2019 – report

The workshop “UV-B and Climate Change; impacts on plants and vegetation” was held in Cork, Ireland, on 15 & 16 April 2019. The overarching aim of the workshop was to explore the interactive effects of UV-B and climate change parameters on plants and vegetation.

A total of 28 researchers attended the workshop, which was organised under the auspices of the International Association for Plant UV-research (UV4Plants). The workshop was hosted by University College Cork (UCC) and generously sponsored by the Irish Environmental Protection Agency (EPA) and Science Foundation Ireland (SFI). Attendees came from Ireland, Norway, Finland, Sweden, Hungary, Czech Republic, Slovenia, Germany, Belgium, France, and Mexico, and the group displayed a good gender balance (13/15) and a mix of early career stage (11) and more established researchers (17). The meeting was organised by Marcel Jansen (School of Biological, Earth and Environmental Sciences, University College Cork, Ireland) with the help of a Scientific Committee comprised of Éva Hideg (Department of Plant Biology, Institute of Biology, University of Pécs, Hungary) and Otmar Urban (Laboratory of Ecological Plant Physiology, CzechGlobe, Brno, Czech Republic).

Workshop attendees on the beach
Fig. 1 – Attendees ended day one by getting truly fresh air at Myrtleville Beach, Co. Cork

Sunshine, heatwaves and drought

Attendees braved tough weather on Monday April 15 (54.6 mm rain; wind gusts of up to 45 knots, and a grand total of 0.0 hours of sunshine), but inside the meeting room the talk was all about sunshine, heatwaves and drought. Matt Robson (Helsinki), co-author of the recent quadrennial report of the UNEP Environmental Effects Assessment Panel, gave an introductory overview of anticipated changes in both UV-B and climate, emphasising the local character of many of the changes. Thus, climate change will be accompanied by decreasing UV levels in some places, but increasing levels in other places, especially those where tropospheric air quality is improving.

Phenology was central in the first session on Monday. Astrid Wingler (Cork) and Line Nybakken (Ås) discussed the complex effects of climate change on phenology, and how UV exposure can impede the climate change-induced delay in autumnal leaf shedding and/or bud set, thus impacting on the length of the growing season.

A range of studies focussed on the co-exposure with high UV, high CO2, high temperatures, and drought. Otmar Urban (Brno) gave a detailed overview of the responses of various woody species exposed to combinations of UV and elevated CO2. The message was that UV potentially diminishes the increases in photosynthesis caused by enhanced CO2. Kristóf Csepregi (Pécs) reported on the interactions between UV and low temperatures, and how UV can induce cross-tolerance. Diana Sáenz de la O (Queretaro) and Louise Ryan (Cork) reported on interactive responses to UV and drought. The role of Reactive Oxygen Species was further detailed by Éva Hideg (Pécs) and Arnold Rácz (Pécs). Anikó Mátai (Pécs) reported that β-aminobutyric acid can induce antioxidant defences, and potentially modify UV-responses. Flavonoids are important antioxidants and their protective potential was highlighted in several talks. Regulation of flavonoid accumulation was explored by Els Prinsen (Antwerpen) and Jakub Nezval (Ostrava). Frauke Peschek (Kiel) reported on UV-induced DNA damage in the context of the changing seasons. Barbro Winkler (München) reported on “deep phenotyping”, and emphasised the availability of European platform facilities that are available for plant impact studies. 

To comprehend the interactive effects of multiple climate parameters on plant growth, Ivan Couée (Rennes) presented a conceptual model that identified integrative signalling hubs, convergence points, in the plant. A talk by Juergen Kreyling (Greifswald), with the fascinating title “To replicate or not to replicate – that is the question” focussed on development of advanced experimental design that is suitable for complex climate studies. A strong case was made for unreplicated, gradient design.

A special scenario in the climate change context is the increasing distribution of plants to higher altitudes where UV levels are high. Two studies reflected on the environmental parameters that determine plant growth at high altitudes. Tadeja Trošt (Ljubljana) reported how slope orientation (i.e. north, south, east, west) affects biochemical and anatomical characteristics of plants in the Slovenian Alps, while Gaia Crestani (Pisa & Cork) reported on the adaptive strategy of maca, a crop grown in the Peruvian Andes at altitudes above 4000m.

Although the meeting was “plant focussed”, two highly relevant non-plant studies were presented. Knut Solhaug (Ås) presented the case of low and high melanin accumulating lichens. While melanin offers protection against high light, this is accompanied by warming of the lichens. This will present a complex trade-off with increasing global warming. Finally, Gary Kett (Cork) presented the interesting case of cultured pacific oysters which are threatened by various pathogens in warmer summers. The case was presented that UV radiation contributes to the lowering of pathogen infection rates, a finding with potentially commercial relevance.

Group photo attendees at UCC
Fig. 2 – Attendees gathered at UCC for a second day of talks and discussions

Discussions

Discussions focussed on the direction of future research and were led by Matt Robson (Helsinki), Åke Strid (Örebro), Wolfgang Bilger (Kiel) and Marcel Jansen (Cork). In the first discussion session, the emphasis was on the “perceived gap” between laboratory and field experiments, and on how this void can be bridged. Overall, the delegates were positive concerning the integration of laboratory and field sciences as the climate conditions in growth chambers are gradually becoming more realistic, especially with the development of high output LEDs.

It was recognised that one important reason to do laboratory research was to explore, in a more controlled environment, findings made under field conditions and/or hypotheses derived based on fieldwork. Conversely, it was argued that fieldwork should be inspired by advances in our understanding of fundamental plant responses, acquired in laboratory studies. Especially the use of characterised mutants in ecological studies should be encouraged as this can generate novel insights in plant responses. Furthermore, it was argued that “hybrid experiments” whereby plants are pre-grown in growth rooms prior to transfer to outdoor experiments, or alternatively, where plants are grown outdoors prior to exposure to UV or climate change under controlled lab conditions, can meaningfully contribute to bridging the knowledge gap between laboratory and field sciences. Overall, communication between disciplines was seen to be a factor of major importance, and this confirms the relevance of small discussion-intensive workshops such as this one, and others.

In the second discussion session, the focus was on the reason why so many of the “studies of interactive effects of climate change and UV” give such variable (or even unpredictable) responses. Various aspects were discussed, including the lack of consideration of leaf and/or plant developmental age. In the workshop, several studies showed that depending on leaf/plant age and/or exposure time, different physiological outcomes do occur. The species specificity of plant responses has also been noted. Finally, the quality (or lack of) UV measurements was discussed. This is a long-standing problem, relating to available equipment and/or calibration.

A major concern is that many experiments involve just one UV-dose and/or one climate change condition. Related to this, there is no reason to believe that UV (and climate parameter-induced) responses will necessarily be linear, and it can be speculated that a mild increase in temperature together with a mild increase in UV cause cross-tolerance, but a higher increase in temperature together with a substantial increase in UV cause cross-sensitivity (i.e. aggravated stress). This relates to the point that for practical reasons many research groups are restrained to do small experiments, which do not necessarily capture the complexity (i.e. full dose response) of the interactions between climate change and altered UV. Therefore, the final session of the meeting focussed on the development of joint “phytometer” experiments whereby similar experiments are performed simultaneously in different countries. This positive engagement is an important outcome of the workshop, and practical benefits of the meeting will be reaped over the coming years. Mirroring this positive outlook, the meeting started in a howling rainstorm on April 15 (Fig. 1), but ended up with much brighter weather on the 16th (Fig. 2).

Marcel Jansen
University College Cork
M.jansen@ucc.ie

UNEP-report on the effects of stratospheric ozone depletion published

The latest UNEP-report on the effects of stratospheric ozone depletion has now been published.

The “Montreal Protocol on Substances that Deplete the Ozone Layer” is a global agreement to protect the Earth’s ozone layer by phasing out the production and consumption of ozone-depleting substances, such as CFC’s. The global agreement was signed in 1987 and is an example of a highly successful international effort to protect the biosphere. In fact, the Montreal Protocol has helped to avoid large, and potentially catastrophic, increases of solar UV‑B radiation in the biosphere. As part of the Montreal Protocol, the Environmental Effects Assessment Panel assesses impacts of ozone layer depletion and changes in UV-radiation. The panel is made up of scientists from throughout the world, and especially experts in photobiology and photochemistry. Prof. Marcel Jansen is the Irish co-author of the report.

Cover of the UNEP report "Environmental Effects and Interactions of Stratospheric Ozone Depletion, UV Radiation, and Climate Change"

The 2018 report, “Environmental Effects and Interactions of Stratospheric Ozone Depletion, UV Radiation, and Climate Change: 2018 Assessment Report”, also known as the “ninth Quadrennial Assessment”, has now been published. The full report can be downloaded directly from the UNEP website (https://ozone.unep.org/science/assessment/eeap). The 381-pages report captures the latest scientific understanding on impacts of ozone layer depletion. The ninth Quadrennial Assessment places strong emphasis on the novel challenge of interactive effects of ozone depletion and climate change on human health and the environment. 

Chapter 3, entitled “Linkages between stratospheric ozone, UV radiation and climate change:  Implications for terrestrial ecosystems”, assesses the effects of stratospheric ozone depletion and associated changes in ultraviolet-B radiation (UV‑B, 280-315 nm) on terrestrial biota, and especially the role of climate change in mediating effects of UV‑B radiation on organisms and ecosystems. The report states that “in some regions ozone depletion is itself contributing to climate change such that ecosystems are being affected by the consequent ozone-driven changes in temperature, precipitation and UV‑B radiation”. In other cases interactive effects of ozone depletion, UV‑B radiation and climate change impact directly on terrestrial organisms and ecosystems, including agricultural systems. Thus, co-exposure to UV‑B and drought, heat or elevated CO2 levels result in new challenges for living organisms, and for the scientists studying these interactive effects.

Research projects participating in Culture Night

Friday 21 September was Culture Night in Cork, and many venues opened their doors for the evening to show their activities.

The School of Biological, Earth and Environmental Sciences (BEES) in UCC was also open. Some 450 visitors were able to get close to hedgehogs, shark jaws, lava, amazing plants and fossils. Many students explained the research project they are working on.

The display of the AQUASUS project in the glass houses explained how duckweed can be used to treat wastewater from fish farms, after which it can be used as animal feed.

Explaining the circular system of purifying wastewater using duckweed

Indoors the project on the Impacts of Microplastics in Irish Freshwater (IMP) explained the problem of small pieces of plastic. Many people know about plastic in our oceans, but it causes problems in our rivers as well.

Display of the IMP project on the Impacts of Microplastics in Irish Freshwater

Minister visits School of BEES

On Monday 3 September minister John Halligan T.D., Minister of State for Training, Skills, Innovation, Research and Development, visited the School of BEES, UCC. We were delighted to show him details of our research for the AQUASUS project. AQUASUS looks at the natural ability of duckweed and algae to thrive in and purify polluted water, producing both clean water for fish farms and a supply of animal feed, as duckweed and algae are edible and high in protein.

The project is funded by European Maritime Fisheries Fund (EMFF), administered by Bord Iascaigh Mhara (BIM) on behalf of the Department of Agriculture, Food and the Marine.

Prof. Marcel Jansen in discussion with Minister John Halligan T.D. during his visit to UCC

SFI Investigator Award for Project on UV-emitting LEDs

Professor Marcel Jansen has been awarded a prestigious SFI Investigator award for work on UV‑emitting LEDs.

At a ceremony in Dublin, Professor Mark Ferguson, Director General of Science Foundation Ireland (SFI), formally announced the awards in the presence of Minister John Halligan T.D., Minister of State for Training, Skills, Innovation, Research and Development. The Minister expressed his strong support for Science and Ireland, and in his speech emphasised the importance of teaching the STEM topics across the entire curriculum from primary school on wards.

Prof Mark Ferguson (SFI), Prof Rosemary O’Connor (UCC), Minister John Halligan John Halligan T.D., Prof Andy Wheeler (UCC) and Prof Marcel Jansen (UCC) at the awards ceremony in Dublin
Prof. Mark Ferguson (SFI), Prof. Rosemary O’Connor (UCC), Minister John Halligan T.D., Prof. Andy Wheeler (UCC) and Prof. Marcel Jansen (UCC) at the SFI awards ceremony in Dublin

The project led by Professor Jansen is entitled “Exploiting narrow‑band UV‑LEDs for Sustainable, Innovative, Technology‑Enabled Cropping (UV‑SINTEC)”. UV‑SINTEC is a joint project between Professor Marcel Jansen (School of Biological, Earth and Environmental Sciences -BEES) and Dr Alan Morrison (Department of Electrical and Electronic Engineering -EEE). UV‑SINTEC will exploit novel ultraviolet (UV)‑emitting LEDs to pioneer a new form of precision agriculture. UV light can improve crop quality in terms of nutritional quality, plant architecture and resistance to pests. This has positive impacts on the sustainability of food production, and human health and well‑being. The SFI‑funded study will develop state‑of‑the‑art LED technology that will enable manipulation of UV doses and spectra, and advance our understanding of how plants respond positively to UV wavelengths. This has not been possible until now due to the limitations of current UV technologies. The pioneering combination of electronic engineering and plant biology will generate innovative technology enabling the horticultural industry to sustainably grow crops with enhanced quality.

The project which will start 1/12/2017 will initially employ 6 new researchers (post graduate, post doctoral, or research assistant) but further spin‑offs, both commercial and academic, are expected.