Browsing by Author "Bruesewitz, Denise A."

Now showing 1 - 2 of 2
  • Thumbnail Image
    Global patterns and drivers of ecosystem functioning in rivers and riparian zones
    Tiegs, Scott D.; Costello, David M.; Isken, Mark W.; Woodward, Guy; McIntyre, Peter B.; Gessner, Mark O.; Chauvet, Eric; Griffiths, Natalie A.; Flecker, Alex S.; Acuna, Vicenc; Albarino, Ricardo; Allen, Daniel C.; Alonso, Cecilia; Andino, Patricio; Arango, Clay; Aroviita, Jukka; Barbosa, Marcus V. M.; Barmuta, Leon A.; Baxter, Colden V.; Bell, Thomas D. C.; Bellinger, Brent; Boyero, Luz; Brown, Lee E.; Bruder, Andreas; Bruesewitz, Denise A.; Burdon, Francis J.; Callisto, Marcos; Canhoto, Cristina; Capps, Krista A.; Castillo, Maria M.; Clapcott, Joanne; Colas, Fanny; Colon-Gaud, Checo; Cornut, Julien; Crespo-Perez, Veronica; Cross, Wyatt F.; Culp, Joseph M.; Danger, Michael; Dangles, Olivier; de Eyto, Elvira; Derry, Alison M.; Diaz Villanueva, Veronica; Douglas, Michael M.; Elosegi, Arturo; Encalada, Andrea C.; Entrekin, Sally A.; Espinosa, Rodrigo; Ethaiya, Diana; Ferreira, Veronica; Ferriol, Carmen; Flanagan, Kyla M.; Fleituch, Tadeusz; Shah, Jennifer J. Follstad; Frainer, Andre; Friberg, Nikolai; Frost, Paul C.; Garcia, Erica A.; Lago, Liliana Garcia; Garcia Soto, Pavel Ernesto; Ghate, Sudeep; Giling, Darren P.; Gilmer, Alan; Goncalves, Jose Francisco, Jr.; Gonzales, Rosario Karina; Graca, Manuel A. S.; Grace, Mike; Grossart, Hans-Peter; Guerold, Francois; Gulis, Vlad; Hepp, Luiz U.; Higgins, Scott; Hishi, Takuo; Huddart, Joseph; Hudson, John; Imberger, Samantha; Iniguez-Armijos, Carlos; Iwata, Tomoya; Janetski, David J.; Jennings, Eleanor; Kirkwood, Andrea E.; Koning, Aaron A.; Kosten, Sarian; Kuehn, Kevin A.; Laudon, Hjalmar; Leavitt, Peter R.; Lemes da Silva, Aurea L.; Leroux, Shawn J.; Leroy, Carri J.; Lisi, Peter J.; MacKenzie, Richard; Marcarelli, Amy M.; Masese, Frank O.; Mckie, Brendan G.; Oliveira Medeiros, Adriana; Meissner, Kristian; Milisa, Marko; Mishra, Shailendra; Miyake, Yo; Moerke, Ashley; Mombrikotb, Shorok; Mooney, Rob; Moulton, Tim; Muotka, Timo; Negishi, Junjiro N.; Neres-Lima, Vinicius; Nieminen, Mika L.; Nimptsch, Jorge; Ondruch, Jakub; Paavola, Riku; Pardo, Isabel; Patrick, Christopher J.; Peeters, Edwin T. H. M.; Pozo, Jesus; Pringle, Catherine; Prussian, Aaron; Quenta, Estefania; Quesada, Antonio; Reid, Brian; Richardson, John S.; Rigosi, Anna; Rincon, Jose; Risnoveanu, Geta; Robinson, Christopher T.; Rodriguez-Gallego, Lorena; Royer, Todd V.; Rusak, James A.; Santamans, Anna C.; Selmeczy, Geza B.; Simiyu, Gelas; Skuja, Agnija; Smykla, Jerzy; Sridhar, Kandikere R.; Sponseller, Ryan; Stoler, Aaron; Swan, Christopher M.; Szlag, David; Teixeira-de Mello, Franco; Tonkin, Jonathan D.; Uusheimo, Sari; Veach, Allison M.; Vilbaste, Sirje; Vought, Lena B. M.; Wang, Chiao-Ping; Webster, Jackson R.; Wilson, Paul B.; Woelfl, Stefan; Xenopoulos, Marguerite A.; Yates, Adam G.; Yoshimura, Chihiro; Yule, Catherine M.; Zhang, Yixin X.; Zwart, Jacob A. (American Association for the Advancement of Science, 2019-01-09)
    River ecosystems receive and process vast quantities of terrestrial organic carbon, the fate of which depends strongly on microbial activity. Variation in and controls of processing rates, however, are poorly characterized at the global scale. In response, we used a peer-sourced research network and a highly standardized carbon processing assay to conduct a global-scale field experiment in greater than 1000 river and riparian sites. We found that Earth’s biomes have distinct carbon processing signatures. Slow processing is evident across latitudes, whereas rapid rates are restricted to lower latitudes. Both the mean rate and variability decline with latitude, suggesting temperature constraints toward the poles and greater roles for other environmental drivers (e.g., nutrient loading) toward the equator. These results and data set the stage for unprecedented “next-generation biomonitoring” by establishing baselines to help quantify environmental impacts to the functioning of ecosystems at a global scale.
  • Thumbnail Image
    Intra- and inter-annual variability in metabolism in an oligotrophic lake
    Richardson, David C.; Carey, Cayelan C.; Bruesewitz, Denise A.; Weathers, Kathleen C. (2017-04)
    Lakes are sentinels of change in the landscapes in which they are located. Changes in lake function are reflected in whole-system metabolism, which integrates ecosystem processes across spatial and temporal scales. Recent improvements in high-frequency open-water metabolism modeling techniques have enabled estimation of rates of gross primary production (GPP), respiration (R), and net ecosystem production (NEP) at high temporal resolution. However, few studies have examined metabolic rates over daily to multi-year temporal scales, especially in oligotrophic ecosystems. Here, we modified a metabolism modeling technique to reveal substantial intra- and inter-annual variability in metabolic rates in Lake Sunapee, a temperate, oligotrophic lake in New Hampshire, USA. Annual GPP and R increased each summer, paralleling increases in littoral, but not pelagic, total phosphorus concentrations. Storms temporarily decoupled GPP and R, resulting in greater decreases in GPP than R. Daily rates of GPP and R were positively correlated on warm days that had stable water columns, and metabolism model fits were best on warm, sunny days, indicating the importance of lake physics when evaluating metabolic rates. These metabolism data span a range of temporal scales and together suggest that Lake Sunapee may be moving toward mesotrophy. We suggest that functional, integrative metrics, such as metabolic rates, are useful indicators and sentinels of ecosystem change. We also highlight the challenges and opportunities of using high-frequency measurements to elucidate the drivers and consequences of intra- and inter-annual variability in metabolic rates, especially in oligotrophic lakes.