CAPES (Brazil)/NUFFIC (Netherlands) Course to Graduate Students in Aquatic ecology Sponsored by the International Society of Limnology (SIL) Invited Scientist, Sarian Kosten, PhD, Radboud University Nijmegen, The Netherlands Contact Vera L M Huszar, [email protected], Federal University of Rio de Janeiro Phone (5521) 25626759, Fax (5521) 25672009 Metabolism of inland waters: feedbacks between climate change and aquatic greenhouse gas balance. One week course mainly for MSc and PhD students, and young scientists (5 year of PhD) interested in carbon balances in inland waters ecology to be hold in the Brazilian Semiarid‐
Tropical region in the Caatinga biome. Objectives After attending this course the students will be able to 1. Identify major metabolic processes in inland waters 2. Experimentally determine process rates 3. Set up and run a metabolic model 4. Assess greenhouse gas balances 5. Evaluate the (potential) impact of climate change on the greenhouse gas balance in inland waters Dates: Tuesday 14st of July 2014 to Sunday 20th of July 2014 Place: Estação Ecológica do Seridó (Ecological Station of Seridó). The course will be hosted by Universidade Federal do Rio Grande do Norte, Brasil. We will stay during the whole course at the Estação Ecológica do Seridó (Ecological Station of Seridó, EES) which is located at the shore of a small reservoir, inside the Caatinga Bioma in a semi‐arid region. The reservoir is regularly monitored for limnological characteristics. There are no fees for the course, housing, and transportation from Natal to Seridó. The students will cover food during the seven days and transportation to reach Natal city, in the State of Rio Grande do Norte. Maximum number of students: 20 Lecturers Dr. Sarian Kosten Radboud University Nijmegen, Netherlands Dr. Jeroen de Klein Wageningen University, Netherlands Dr. Vanessa Becker Universidade Federal do Rio Grande do Norte, Brasil Dr. André Megali Universidade Federal do Rio Grande do Norte, Brasil Dr. Nathan Barros Radboud University Nijmegen, Netherlands Dr. Raquel Mendonça Uppsala University, Sweden Program Students from other places should arrive to Natal on Sunday 13th, because departure from Natal to Ecological Station of Seridó (ESS) on Monday 14th will be early in the morning. Hour Day 1 Mon 14th 06:00 Activity Responsible Departure from UFRN to ESS Vanessa Tue 15th 14:00 18.30 19.00 20.00 20.30 07.30 08.30 9.30 10.30 Vanessa/Sarian Sarian Vanessa Sarian Jeroen all Wed 16th 11.30 12.00 13.00 19.00 20.00 7.30 8.30 12.00 13.00 Lunch in Seridó (Caicó village) Welcome at the field station Dinner Short introduction into Aquatic oxygen and carbon dynamics Introduction to the research site Breakfast Week overview “oxygen and carbon budgets” Lecture: Carbon modelling Detailed instructions for lab essays and field measurements. Chlorophyll (phytopam) [1 per group]. Primary production, respiration. Sediment‐water and Water‐atmosphere gas fluxes (diffusive & ebullition). Water – atmosphere gas diffusion coefficient. Methane oxidation Preparation lab and fieldwork Lunch Lab essays & field measurements I Dinner Lecture: Metabolism of aquatic ecosystems in a changing world Breakfast Lab essays & field measurements II Lunch Lab essays & field measurements III all Sarian 19.00 Thu 17th 7.30 8.30 12.00 13.00 19.00 20.00 Fri 18th 7.30 8.30 12.00 13.00 19.00 20.00 Sat 19th 7.30 8.30 12.00 13.00 20.00 Sun 20th 7.00 8.00 9.15 9.30 10.45 11.15 12.00 Dinner Evening lecture: (topics: modelling, wetland N2O emissions, link between oxygen and nutrient dynamics) Breakfast Lab essays & field measurements IV Lunch Lab essays & field measurements V Dinner Evening lecture: (topics: carbon budget case studies, importance of burial assessment, climate influence on outgassing) Breakfast Lab essays & field measurements VI Lunch Modelling and further elaboration lab essays and field measurement Preparation presentations Dinner Evening lecture: (topics: Impact of climate on eutrophication and possible remediation techniques and its subsequent effect on aquatic metabolism) Breakfast Modelling and further elaboration lab essays and field measurement Preparation presentations Lunch Modelling and further elaboration lab essays and field measurement Preparation presentations Evening lecture: (Topics: role of hydrology on phytoplankton dynamics) Breakfast Group presentation (1‐3) Coffee Group presentation (4‐6) Closing Lunch Departure to Natal (Airport and UFRN) Jeroen Nathan & Raquel André/Vanessa Vanessa Practical schedule Tuesday GROUP Afternoon (I) 1 Spatial variation Wednesday Morning (II) Afternoon (III) Water Methane atmosphere oxidation gas fluxes2) Spatial Water variation atmosphere gas fluxes1) Plankton Spatial P&R variation 2 Plankton P&R 3 Sediment respiration 4 Gas diffusion Sediment coefficient respiration 5 Methane Plankton P&R Gas diffusion Sediment Thursday Morning Afternoon (IV) (V) Gas Sediment diffusion respiration coefficient Methane Gas diffusion oxidation coefficient Friday Morning (VI) Plankton P&R Water atmosphere gas fluxes2) Spatial variation Gas diffusion coefficient Methane oxidation Plankton Methane oxidation Water atmosphere gas fluxes1) Spatial Sediment respiration Water 6 oxidation coefficient respiration P&R variation Water atmosphere gas fluxes1) Methane oxidation Gas diffusion coefficient Sediment respiration Plankton P&R atmosphere gas fluxes2) Spatial variation 1) Last measurement at 10.00 pm 2) First measurement at 5.30 am (before sunrise) Background Although inland waters occupy only 3% of the Earth’s surface, they play an important role in the global carbon cycle by processing large amounts of terrestrially derived carbon (Cole et al., 2007; Downing et al., 2008; Duarte et al., 2008). A recent review, for example, estimated that the amount of CO2 emitted from inland waters globally is similar to that taken up by the oceans (Tranvik et al., 2009). Especially shallow lakes and reservoirs are of importance (Tranvik et al., 2009). Although, they can function as net carbon sinks through carbon sedimentation (Mendonça et al., 2012), they often become supersaturated with carbon gases and then act as carbon sources to the atmosphere. Their functioning depends on physical, chemical, and biological processes such as respiration and primary production (Cole et al., 1994; Cole et al., 2000; Duarte & Prairie, 2005; Sobek, Tranvik & Cole, 2005). All these processes are sensitive to climate change so that warmer systems tend to emit more carbon (Kosten et al., 2010; Gudasz et al., 2010). The temperature effect on metabolic rates, however, is only one of the many climatic effects altering the carbon balance of ecosystems. Climate change induced shifts in species composition and its interplay with eutrophication may alter the direct temperature effect on ecosystem’s metabolism (Moss et al., 2011). We illustrate this using one of the most discussed effects of climate change effects in aquatic systems: the enhanced occurrence of cyanobacterial blooms (Paerl & Huisman, 2008; Kosten et al., 2012). On one hand, the high photosynthetic rates during cyanobacterial blooms enhance the freshwater CO2 sink. Phytoplankton communities are one of the most efficient biological systems to capture carbon (Sayre, 2010). At the same time, however, high temperatures increase respiration rates even more. The differential temperature effect on photosynthetic and respiration rates (see figure 1), in turn leads to more CO2 emission to the atmosphere. The high sedimentation of phytoplankton biomass during and after a bloom leads to organic carbon burial in sediments, removing CO2 from the atmosphere for long time‐scales (Dean & Gorham, 1998; Cole et al., 2007). On the other hand, the intense organic matter decomposition in the sediment may lead to high CO2 release and when the sediment becomes anoxic also to more CH4 production (Bastviken et al., 2008). Importantly, the global warming potential of CH4 is about 25 times higher than that of CO2 (IPCC, 2007). The high primary production during a bloom, however, leads to high daytime oxygen concentrations at the epilimnion, enhancing CH4 oxidation into CO2 and subsequently decreasing CH4 emissions. At night the high respiration by the cyanobacteria may, however, lead to anoxia in the water column as well, potentially further enhancing both CO2 and CH4 emissions. The net effect of cyanobacterial blooms is therefore not straight forward. Figure 1. Current indications of feedback effects of eutrophication and the enhancement of cyanobacterial growth on climate change. Blue arrows indicate carbon sequestration routes; red arrows indicate carbon emission routes; black arrows indicate other climate effects. Because CO2 uptake and release may both increase with eutrophication, net CO2 balance is unclear. The increase in methane and nitrous oxide is more probable (Moss et al. 2011). There are different ways in which the metabolic balance of aquatic systems can be assessed. During the course we will use different approaches and compare their outcome. (1) The classical way of studying aquatic metabolism is to use diel oxygen change curves (Odum & Hoskin, 1958)(Seeley, 1969). Based on these curves ecosystem respiration and net ecosystem production can be determined. By using a simple ‐approximate‐ conversion factor subsequently the CO2 exchange between the aquatic system and the atmosphere can be estimated (e.g. Barros et al. in prep). (2) CO2 fluxes between water and atmosphere can also be measured directly (using e.g. floating top chambers) or estimated based on the partial CO2 pressure in the water. In the same way water‐atmosphere methane fluxes can be determined. (3) One can also experimentally determine the rates of the main metabolic processes in the system (such as primary production, plankton respiration and sediment respiration) and combine these to estimate the metabolic balance of the system. The combination of these different processes typically takes place in a dynamic model. References Bastviken, D., Cole, J.J., Pace, M.L. & Van De Bogert, M.C. (2008) Fates of methane from different lake habitats: Connecting whole‐lake budgets and CH4 emissions. J. Geophys. Res., 113, G02024. Cole, J.J., Caraco, N.F., Kling, G.W. & Kratz, T.K. (1994) Carbon‐dioxide supersaturation in the surface waters of lakes. Science, 265, 1568‐1570. Cole, J.J., Pace, M.L., Carpenter, S.R. & Kitchell, J.F. (2000) Persistence of net heterotrophy in lakes during nutrient addition and food web manipulations. Limnology and Oceanography, 45, 1718‐1730. Cole, J.J., Prairie, Y., Caraco, N.F., Mcdowell, W.H., Tranvik, L.J., Striegl, R.G., et al. (2007) Plumbing the global carbon cycle: Integrating inland waters into the terrestrial carbon budget. Ecosystems, 10, 172‐185. Dean, W.E. & Gorham, E. (1998) Magnitude and significance of carbon burial in lakes, reservoirs, and peatlands. Geology, 26, 535‐538. Downing, J.A., Cole, J.J., Middelburg, J.J., Striegl, R.G., Duarte, C.M., Kortelainen, P., et al. (2008) Sediment organic carbon burial in agriculturally eutrophic impoundments over the last century. Global Biogeochemical Cycles, 22. Duarte, C.M. & Prairie, Y.T. (2005) Prevalence of heterotrophy and atmospheric CO2 emissions from aquatic ecosystems. Ecosystems, V8, 862‐870. Duarte, C.M., Prairie, Y.T., Montes, C., Cole, J.J., Striegl, R., Melack, J., et al. (2008) CO2 emissions from saline lakes: A global estimate of a surprisingly large flux. J. Geophys. Res., 113. Gudasz, C., Bastviken, D., Steger, K., Premke, K., Sobek, S. & Tranvik, L.J. (2010) Temperature‐
controlled organic carbon mineralization in lake sediments. Nature, 466, 478‐481. Ipcc (2007) Climate Change 2007: Synthesis Report. 52. Kosten, S., Huszar, V.L.M., Bécares, E., Costa, L.S., Van Donk, E., Hansson, L.A., et al. (2012) Warmer climate boosts cyanobacterial dominance in lakes. Global Change Biology, 18, 118–126. Kosten, S., Roland, F., Da Motta Marques, D.M.L., Van Nes, E.H., Mazzeo, N., Sternberg, L.D.S.L., et al. (2010) Climate‐dependent CO2 emissions from lakes. Global Biogeochemical Cycles, 24, GB2007. Mendonça, R., Kosten, S., Sobek, S., Barros, N., Cole, J.J., Tranvik, L., et al. (2012) Hydroelectric carbon sequestration. Nature Geoscience, 5, 838‐840. Moss, B., Kosten, S., Meerhoff, M., Battarbee, R.W., Jeppesen, E., Mazzeo, N., et al. (2011) Allied attack: climate change and nutrient pollution. Inland waters, 18, 101‐105. Odum, H.T. & Hoskin, C.M. (1958) Comparative studies on the metabolism of marine waters. Publications of the Institute of Marine Science, Texas, 5, 16‐46. Paerl, H.W. & Huisman, J. (2008) Blooms like it hot. Science, 320, 57‐58. Sayre, R. (2010) Microalgae: The Potential for Carbon Capture. BioScience, 60, 722‐727. Seeley, C.M. (1969) The diurnal curve in estimates of primary productivity. Chesapeake Science, 10, 322‐326. Sobek, S., Tranvik, L. & Cole, J. (2005) Temperature independence of carbon dioxide supersaturation in global lakes. Global Biogeochemical Cycles, 19, GB2003. Tranvik, L.J., Downing, J.A., Cotner, J.B., Loisell, S.A., Striegl, R.G., Ballatore, T.J., et al. (2009) Lakes and reservoirs as regulators of carbon cycling and climate. Limnology and Oceanography, 54, 2298‐2314. Curriculum Vitae resumido (Sarian Kosten) In 2010 she defended her PhD thesis ‘Aquatic ecosystems in hot water: effects of climate on the functioning of shallow lakes’. She received her PhD title cum laude. Currently she works as a researcher the Aquatic Ecology & Water Quality Management Group, Department of Environmental Sciences of the Wageningen University and Research Centre (The Netherlands) and as a guest researcher at the Leibniz‐Institute of Freshwater Ecology and Inland Fisheries (IGB) in Berlin and Neuglobsow (Germany). Main scientific interests and research areas: Effects of climate change on aquatic ecology and water quality; The carbon balance of inland waters; Factors influencing the competition between different groups of primary producers (macrophytes, algae and cyanobacteria). From 1999 she worked successively for the IVN (Association of Nature and Environmental Education), the Communication and Innovation Group, and the Aquatic Ecology and Water Quality Management Group at the Wageningen University focusing on various aspects of water management. In 2003 she obtained a Junior Professional Officer position at the South American office of the IUCN‐World Conservation Union (Ecuador) where she coordinated wetland conservation projects. From 2004 till 2009 she worked on her PhD research focusing on the influence of climate on lakes’ metabolism and the competition between submerged macrophytes and phytoplankton. Afterwards she continued working for the Wageningen University, now within the Knowledge for Climate Programme studying the impact of climate change on Dutch surface water quality. Since 2013 she works at the Radboud University Nijmegen. Her work concentrates on climate change effects on the carbon balance of inland waters, aquatic ecology, and water quality. Selected Publications: Kosten, S., B.O. Demars, and B. Moss, Distinguishing autotrophic and heterotrophic respiration based on diel oxygen change curves: revisiting Dr. Faustus. Freshwater Biology, 2014. 59(3): p. 649‐651. Mendonça, R., S. Kosten, S. Sobek, J. Cole, A. Bastos, A. Albuquerque, S. Cardoso and F. Roland (2014). "Carbon Sequestration in a Large Hydroelectric Reservoir: An Integrative Seismic Approach." Ecosystems 17(3): 430‐441. Brothers, S.M., S. Hilt, K. Attermeyer, H.P. Grossart, S. Kosten, B. Lischke, T. Mehner, N. Meyer, K. Scharnweber, and J. Köhler, A regime shift from macrophyte to phytoplankton dominance enhances carbon burial in a shallow, eutrophic lake. Ecosphere, 2013. 4(11): p. art137. Kosten S, Huszar VLM, Bécares E, Costa LS, Donk E, Hansson L‐A, Jeppesen E,Kruk C, Lacerot G, Mazzeo N, Meester L, Moss B, Lürling M, Nõges T, Romo S, Scheffer M. 2012. Warmer climates boost cyanobacterial dominance in shallow lakes. Global Change Biology 18, 118‐126. Mendonça, R., S. Kosten, S. Sobek, N. Barros, J.J. Cole, L. Tranvik, and F. Roland, Hydroelectric carbon sequestration. Nature Geoscience, 2012. 5(12): p. 838‐840. Kosten S, Jeppesen E, Huszar VLM, Mazzeo N, van Nes EH, Peeters ETHM, Scheffer M. 2011. Ambiguous climate impacts on the stability of alternative states in shallow lakes. Freshwater Biology 56, 1540‐1553. Moss B, Kosten S, Battarbee RW, Jeppesen E, Mazzeo N, Havens K, Lacerot G, Liu Z, De Meester L, Paerl HW, Scheffer M. 2011. Allied attack: climate change and nutrient pollution. Inland Waters 101‐105. Kosten S, Roland F, Marques DMLM, Nes EV, Mazzeo N, Sternberg LSL, Scheffer M, Cole JJ. 2010. Climate‐dependent CO2 emissions from lakes. Global Biogeochemical Cycles 24, 1‐7. Kosten S, Huszar VLM, Mazzeo N, Scheffer, Sternberg MSL, Jeppesen E. 2009. Lake and watershed characteristics rather than climate influence nutrient limitation in shallow lakes. Ecological Applications 19,1791‐1804.