655 results on '"Vargas, Rodrigo"'
Search Results
2. Characterizing Performance of Freshwater Wetland Methane Models Across Time Scales at FLUXNET‐CH4 Sites Using Wavelet Analyses
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Zhang, Zhen, Bansal, Sheel, Chang, Kuang‐Yu, Fluet‐Chouinard, Etienne, Delwiche, Kyle, Goeckede, Mathias, Gustafson, Adrian, Knox, Sara, Leppänen, Antti, Liu, Licheng, Liu, Jinxun, Malhotra, Avni, Markkanen, Tiina, McNicol, Gavin, Melton, Joe R, Miller, Paul A, Peng, Changhui, Raivonen, Maarit, Riley, William J, Sonnentag, Oliver, Aalto, Tuula, Vargas, Rodrigo, Zhang, Wenxin, Zhu, Qing, Zhu, Qiuan, Zhuang, Qianlai, Windham‐Myers, Lisamarie, Jackson, Robert B, and Poulter, Benjamin
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Earth Sciences ,Atmospheric Sciences ,Climate Action ,Geophysics - Abstract
Process-based land surface models are important tools for estimating global wetland methane (CH4) emissions and projecting their behavior across space and time. So far there are no performance assessments of model responses to drivers at multiple time scales. In this study, we apply wavelet analysis to identify the dominant time scales contributing to model uncertainty in the frequency domain. We evaluate seven wetland models at 23 eddy covariance tower sites. Our study first characterizes site-level patterns of freshwater wetland CH4 fluxes (FCH4) at different time scales. A Monte Carlo approach was developed to incorporate flux observation error to avoid misidentification of the time scales that dominate model error. Our results suggest that (a) significant model-observation disagreements are mainly at multi-day time scales (32 days) for the boreal and Arctic tundra wetland sites but have significant bias in variability at seasonal time scales for temperate and tropical/subtropical sites; (c) model errors exhibit increasing power spectrum as time scale increases, indicating that biases at time scales
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- 2023
3. Upscaling Wetland Methane Emissions From the FLUXNET‐CH4 Eddy Covariance Network (UpCH4 v1.0): Model Development, Network Assessment, and Budget Comparison
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McNicol, Gavin, Fluet‐Chouinard, Etienne, Ouyang, Zutao, Knox, Sara, Zhang, Zhen, Aalto, Tuula, Bansal, Sheel, Chang, Kuang‐Yu, Chen, Min, Delwiche, Kyle, Feron, Sarah, Goeckede, Mathias, Liu, Jinxun, Malhotra, Avni, Melton, Joe R, Riley, William, Vargas, Rodrigo, Yuan, Kunxiaojia, Ying, Qing, Zhu, Qing, Alekseychik, Pavel, Aurela, Mika, Billesbach, David P, Campbell, David I, Chen, Jiquan, Chu, Housen, Desai, Ankur R, Euskirchen, Eugenie, Goodrich, Jordan, Griffis, Timothy, Helbig, Manuel, Hirano, Takashi, Iwata, Hiroki, Jurasinski, Gerald, King, John, Koebsch, Franziska, Kolka, Randall, Krauss, Ken, Lohila, Annalea, Mammarella, Ivan, Nilson, Mats, Noormets, Asko, Oechel, Walter, Peichl, Matthias, Sachs, Torsten, Sakabe, Ayaka, Schulze, Christopher, Sonnentag, Oliver, Sullivan, Ryan C, Tuittila, Eeva‐Stiina, Ueyama, Masahito, Vesala, Timo, Ward, Eric, Wille, Christian, Wong, Guan Xhuan, Zona, Donatella, Windham‐Myers, Lisamarie, Poulter, Benjamin, and Jackson, Robert B
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Earth Sciences ,Atmospheric Sciences ,Climate Action ,Life on Land ,Climate change science ,Geology ,Physical geography and environmental geoscience - Abstract
Wetlands are responsible for 20%–31% of global methane (CH4) emissions and account for a large source of uncertainty in the global CH4 budget. Data-driven upscaling of CH4 fluxes from eddy covariance measurements can provide new and independent bottom-up estimates of wetland CH4 emissions. Here, we develop a six-predictor random forest upscaling model (UpCH4), trained on 119 site-years of eddy covariance CH4 flux data from 43 freshwater wetland sites in the FLUXNET-CH4 Community Product. Network patterns in site-level annual means and mean seasonal cycles of CH4 fluxes were reproduced accurately in tundra, boreal, and temperate regions (Nash-Sutcliffe Efficiency ∼0.52–0.63 and 0.53). UpCH4 estimated annual global wetland CH4 emissions of 146 ± 43 TgCH4 y−1 for 2001–2018 which agrees closely with current bottom-up land surface models (102–181 TgCH4 y−1) and overlaps with top-down atmospheric inversion models (155–200 TgCH4 y−1). However, UpCH4 diverged from both types of models in the spatial pattern and seasonal dynamics of tropical wetland emissions. We conclude that upscaling of eddy covariance CH4 fluxes has the potential to produce realistic extra-tropical wetland CH4 emissions estimates which will improve with more flux data. To reduce uncertainty in upscaled estimates, researchers could prioritize new wetland flux sites along humid-to-arid tropical climate gradients, from major rainforest basins (Congo, Amazon, and SE Asia), into monsoon (Bangladesh and India) and savannah regions (African Sahel) and be paired with improved knowledge of wetland extent seasonal dynamics in these regions. The monthly wetland methane products gridded at 0.25° from UpCH4 are available via ORNL DAAC (https://doi.org/10.3334/ORNLDAAC/2253).
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- 2023
4. Practical Guide to Measuring Wetland Carbon Pools and Fluxes.
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Banerjee, Kakoli, Bastviken, David, Berg, Peter, Bogard, Matthew, Chow, Alex, Conner, William, Craft, Christopher, Creamer, Courtney, DelSontro, Tonya, Duberstein, Jamie, Eagle, Meagan, Fennessy, M, Finkelstein, Sarah, Göckede, Mathias, Grunwald, Sabine, Halabisky, Meghan, Herbert, Ellen, Jahangir, Mohammad, Johnson, Olivia, Jones, Miriam, Kelleway, Jeffrey, Knox, Sara, Kroeger, Kevin, Kuehn, Kevin, Lobb, David, Loder, Amanda, Ma, Shizhou, Maher, Damien, McNicol, Gavin, Meier, Jacob, Middleton, Beth, Mills, Christopher, Mistry, Purbasha, Mitra, Abhijit, Mobilian, Courtney, Nahlik, Amanda, Newman, Sue, OConnell, Jessica, Oikawa, Patty, van der Burg, Max, Schutte, Charles, Song, Changchun, Stagg, Camille, Turner, Jessica, Vargas, Rodrigo, Waldrop, Mark, Wallin, Marcus, Wang, Zhaohui, Ward, Eric, Willard, Debra, Yarwood, Stephanie, Zhu, Xiaoyan, Bansal, Sheel, Creed, Irena, Tangen, Brian, Bridgham, Scott, Desai, Ankur, Krauss, Ken, Neubauer, Scott, Noe, Gregory, Rosenberry, Donald, Trettin, Carl, Wickland, Kimberly, Allen, Scott, Arias-Ortiz, Ariane, Armitage, Anna, and Baldocchi, Dennis
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Accretion ,Accumulation ,Biomass ,Bulk density ,Carbon cycling ,Chambers ,Core ,Decomposition ,Dissolved gas ,Dissolved organic carbon ,Eddy covariance ,Greenhouse gas ,Groundwater ,Hydrology ,Incubation ,Lateral transport ,Litter ,Methane ,Methods ,Microbes ,Models ,Net primary productivity ,Plants ,Porewater ,Radiometric dating ,Remote sensing ,Sediment ,Soil organic carbon ,Vegetation ,Water - Abstract
UNLABELLED: Wetlands cover a small portion of the world, but have disproportionate influence on global carbon (C) sequestration, carbon dioxide and methane emissions, and aquatic C fluxes. However, the underlying biogeochemical processes that affect wetland C pools and fluxes are complex and dynamic, making measurements of wetland C challenging. Over decades of research, many observational, experimental, and analytical approaches have been developed to understand and quantify pools and fluxes of wetland C. Sampling approaches range in their representation of wetland C from short to long timeframes and local to landscape spatial scales. This review summarizes common and cutting-edge methodological approaches for quantifying wetland C pools and fluxes. We first define each of the major C pools and fluxes and provide rationale for their importance to wetland C dynamics. For each approach, we clarify what component of wetland C is measured and its spatial and temporal representativeness and constraints. We describe practical considerations for each approach, such as where and when an approach is typically used, who can conduct the measurements (expertise, training requirements), and how approaches are conducted, including considerations on equipment complexity and costs. Finally, we review key covariates and ancillary measurements that enhance the interpretation of findings and facilitate model development. The protocols that we describe to measure soil, water, vegetation, and gases are also relevant for related disciplines such as ecology. Improved quality and consistency of data collection and reporting across studies will help reduce global uncertainties and develop management strategies to use wetlands as nature-based climate solutions. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13157-023-01722-2.
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- 2023
5. Practical Guide to Measuring Wetland Carbon Pools and Fluxes
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Bansal, Sheel, Creed, Irena F., Tangen, Brian A., Bridgham, Scott D., Desai, Ankur R., Krauss, Ken W., Neubauer, Scott C., Noe, Gregory B., Rosenberry, Donald O., Trettin, Carl, Wickland, Kimberly P., Allen, Scott T., Arias-Ortiz, Ariane, Armitage, Anna R., Baldocchi, Dennis, Banerjee, Kakoli, Bastviken, David, Berg, Peter, Bogard, Matthew J., Chow, Alex T., Conner, William H., Craft, Christopher, Creamer, Courtney, DelSontro, Tonya, Duberstein, Jamie A., Eagle, Meagan, Fennessy, M. Siobhan, Finkelstein, Sarah A., Göckede, Mathias, Grunwald, Sabine, Halabisky, Meghan, Herbert, Ellen, Jahangir, Mohammad M. R., Johnson, Olivia F., Jones, Miriam C., Kelleway, Jeffrey J., Knox, Sara, Kroeger, Kevin D., Kuehn, Kevin A., Lobb, David, Loder, Amanda L., Ma, Shizhou, Maher, Damien T., McNicol, Gavin, Meier, Jacob, Middleton, Beth A., Mills, Christopher, Mistry, Purbasha, Mitra, Abhijit, Mobilian, Courtney, Nahlik, Amanda M., Newman, Sue, O’Connell, Jessica L., Oikawa, Patty, van der Burg, Max Post, Schutte, Charles A., Song, Changchun, Stagg, Camille L., Turner, Jessica, Vargas, Rodrigo, Waldrop, Mark P., Wallin, Marcus B., Wang, Zhaohui Aleck, Ward, Eric J., Willard, Debra A., Yarwood, Stephanie, and Zhu, Xiaoyan
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- 2023
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6. Predicting soil organic carbon with different approaches and spatial resolutions for the southern Iberian Peninsula, Spain
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Durante, Pilar, Guevara, Mario, Vargas, Rodrigo, and Oyonarte, Cecilio
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- 2024
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7. Experimentally simulated sea level rise destabilizes carbon-mineral associations in temperate tidal marsh soil
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Fettrow, Sean, Vargas, Rodrigo, and Seyfferth, Angelia L.
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- 2023
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8. Beyond a deterministic representation of the temperature dependence of soil respiration
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Le, Van Huong and Vargas, Rodrigo
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- 2024
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9. Spatial and temporal variation of three Eddy-Covariance flux footprints in a Tropical Dry Forest
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Abdaki, Mohammed, Sanchez-Azofeifa, Arturo, Vargas, Rodrigo, Ludwig, Ralf, and Hamann, Hendrik F.
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- 2024
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10. An autocorrelated conditioned Latin hypercube method for temporal or spatial sampling and predictions
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Le, Van Huong and Vargas, Rodrigo
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- 2024
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11. Gap-filling eddy covariance methane fluxes: Comparison of machine learning model predictions and uncertainties at FLUXNET-CH4 wetlands
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Irvin, Jeremy, Zhou, Sharon, McNicol, Gavin, Lu, Fred, Liu, Vincent, Fluet-Chouinard, Etienne, Ouyang, Zutao, Knox, Sara Helen, Lucas-Moffat, Antje, Trotta, Carlo, Papale, Dario, Vitale, Domenico, Mammarella, Ivan, Alekseychik, Pavel, Aurela, Mika, Avati, Anand, Baldocchi, Dennis, Bansal, Sheel, Bohrer, Gil, Campbell, David I, Chen, Jiquan, Chu, Housen, Dalmagro, Higo J, Delwiche, Kyle B, Desai, Ankur R, Euskirchen, Eugenie, Feron, Sarah, Goeckede, Mathias, Heimann, Martin, Helbig, Manuel, Helfter, Carole, Hemes, Kyle S, Hirano, Takashi, Iwata, Hiroki, Jurasinski, Gerald, Kalhori, Aram, Kondrich, Andrew, Lai, Derrick YF, Lohila, Annalea, Malhotra, Avni, Merbold, Lutz, Mitra, Bhaskar, Ng, Andrew, Nilsson, Mats B, Noormets, Asko, Peichl, Matthias, Rey-Sanchez, A Camilo, Richardson, Andrew D, Runkle, Benjamin RK, Schäfer, Karina VR, Sonnentag, Oliver, Stuart-Haëntjens, Ellen, Sturtevant, Cove, Ueyama, Masahito, Valach, Alex C, Vargas, Rodrigo, Vourlitis, George L, Ward, Eric J, Wong, Guan Xhuan, Zona, Donatella, Alberto, Ma Carmelita R, Billesbach, David P, Celis, Gerardo, Dolman, Han, Friborg, Thomas, Fuchs, Kathrin, Gogo, Sébastien, Gondwe, Mangaliso J, Goodrich, Jordan P, Gottschalk, Pia, Hörtnagl, Lukas, Jacotot, Adrien, Koebsch, Franziska, Kasak, Kuno, Maier, Regine, Morin, Timothy H, Nemitz, Eiko, Oechel, Walter C, Oikawa, Patricia Y, Ono, Keisuke, Sachs, Torsten, Sakabe, Ayaka, Schuur, Edward A, Shortt, Robert, Sullivan, Ryan C, Szutu, Daphne J, Tuittila, Eeva-Stiina, Varlagin, Andrej, Verfaillie, Joeseph G, Wille, Christian, Windham-Myers, Lisamarie, Poulter, Benjamin, and Jackson, Robert B
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Earth Sciences ,Agricultural ,Veterinary and Food Sciences ,Biological Sciences ,Networking and Information Technology R&D (NITRD) ,Bioengineering ,Machine Learning and Artificial Intelligence ,Machine learning ,time series ,imputation ,gap-filling ,methane ,flux ,wetlands ,Agricultural and Veterinary Sciences ,Meteorology & Atmospheric Sciences ,Agricultural ,veterinary and food sciences ,Biological sciences ,Earth sciences - Abstract
Time series of wetland methane fluxes measured by eddy covariance require gap-filling to estimate daily, seasonal, and annual emissions. Gap-filling methane fluxes is challenging because of high variability and complex responses to multiple drivers. To date, there is no widely established gap-filling standard for wetland methane fluxes, with regards both to the best model algorithms and predictors. This study synthesizes results of different gap-filling methods systematically applied at 17 wetland sites spanning boreal to tropical regions and including all major wetland classes and two rice paddies. Procedures are proposed for: 1) creating realistic artificial gap scenarios, 2) training and evaluating gap-filling models without overstating performance, and 3) predicting half-hourly methane fluxes and annual emissions with realistic uncertainty estimates. Performance is compared between a conventional method (marginal distribution sampling) and four machine learning algorithms. The conventional method achieved similar median performance as the machine learning models but was worse than the best machine learning models and relatively insensitive to predictor choices. Of the machine learning models, decision tree algorithms performed the best in cross-validation experiments, even with a baseline predictor set, and artificial neural networks showed comparable performance when using all predictors. Soil temperature was frequently the most important predictor whilst water table depth was important at sites with substantial water table fluctuations, highlighting the value of data on wetland soil conditions. Raw gap-filling uncertainties from the machine learning models were underestimated and we propose a method to calibrate uncertainties to observations. The python code for model development, evaluation, and uncertainty estimation is publicly available. This study outlines a modular and robust machine learning workflow and makes recommendations for, and evaluates an improved baseline of, methane gap-filling models that can be implemented in multi-site syntheses or standardized products from regional and global flux networks (e.g., FLUXNET).
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- 2021
12. High light and temperature reduce photosynthetic efficiency through different mechanisms in the C4 model Setaria viridis.
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Anderson, Cheyenne M, Mattoon, Erin M, Zhang, Ningning, Becker, Eric, McHargue, William, Yang, Jiani, Patel, Dhruv, Dautermann, Oliver, McAdam, Scott AM, Tarin, Tonantzin, Pathak, Sunita, Avenson, Tom J, Berry, Jeffrey, Braud, Maxwell, Niyogi, Krishna K, Wilson, Margaret, Nusinow, Dmitri A, Vargas, Rodrigo, Czymmek, Kirk J, Eveland, Andrea L, and Zhang, Ru
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C4 plants frequently experience high light and high temperature conditions in the field, which reduce growth and yield. However, the mechanisms underlying these stress responses in C4 plants have been under-explored, especially the coordination between mesophyll (M) and bundle sheath (BS) cells. We investigated how the C4 model plant Setaria viridis responded to a four-hour high light or high temperature treatment at photosynthetic, transcriptomic, and ultrastructural levels. Although we observed a comparable reduction of photosynthetic efficiency in high light or high temperature treated leaves, detailed analysis of multi-level responses revealed important differences in key pathways and M/BS specificity responding to high light and high temperature. We provide a systematic analysis of high light and high temperature responses in S. viridis, reveal different acclimation strategies to these two stresses in C4 plants, discover unique light/temperature responses in C4 plants in comparison to C3 plants, and identify potential targets to improve abiotic stress tolerance in C4 crops.
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- 2021
13. Identifying dominant environmental predictors of freshwater wetland methane fluxes across diurnal to seasonal time scales
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Knox, Sara H, Bansal, Sheel, McNicol, Gavin, Schafer, Karina, Sturtevant, Cove, Ueyama, Masahito, Valach, Alex C, Baldocchi, Dennis, Delwiche, Kyle, Desai, Ankur R, Euskirchen, Eugenie, Liu, Jinxun, Lohila, Annalea, Malhotra, Avni, Melling, Lulie, Riley, William, Runkle, Benjamin RK, Turner, Jessica, Vargas, Rodrigo, Zhu, Qing, Alto, Tuula, Fluet‐Chouinard, Etienne, Goeckede, Mathias, Melton, Joe R, Sonnentag, Oliver, Vesala, Timo, Ward, Eric, Zhang, Zhen, Feron, Sarah, Ouyang, Zutao, Alekseychik, Pavel, Aurela, Mika, Bohrer, Gil, Campbell, David I, Chen, Jiquan, Chu, Housen, Dalmagro, Higo J, Goodrich, Jordan P, Gottschalk, Pia, Hirano, Takashi, Iwata, Hiroki, Jurasinski, Gerald, Kang, Minseok, Koebsch, Franziska, Mammarella, Ivan, Nilsson, Mats B, Ono, Keisuke, Peichl, Matthias, Peltola, Olli, Ryu, Youngryel, Sachs, Torsten, Sakabe, Ayaka, Sparks, Jed P, Tuittila, Eeva‐Stiina, Vourlitis, George L, Wong, Guan X, Windham‐Myers, Lisamarie, Poulter, Benjamin, and Jackson, Robert B
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Earth Sciences ,Climate Change Impacts and Adaptation ,Environmental Sciences ,Carbon Dioxide ,Ecosystem ,Fresh Water ,Methane ,Seasons ,Wetlands ,eddy covariance ,generalized additive modeling ,lags ,methane ,mutual information ,predictors ,random forest ,synthesis ,time scales ,wetlands ,Biological Sciences ,Ecology ,Biological sciences ,Earth sciences ,Environmental sciences - Abstract
While wetlands are the largest natural source of methane (CH4 ) to the atmosphere, they represent a large source of uncertainty in the global CH4 budget due to the complex biogeochemical controls on CH4 dynamics. Here we present, to our knowledge, the first multi-site synthesis of how predictors of CH4 fluxes (FCH4) in freshwater wetlands vary across wetland types at diel, multiday (synoptic), and seasonal time scales. We used several statistical approaches (correlation analysis, generalized additive modeling, mutual information, and random forests) in a wavelet-based multi-resolution framework to assess the importance of environmental predictors, nonlinearities and lags on FCH4 across 23 eddy covariance sites. Seasonally, soil and air temperature were dominant predictors of FCH4 at sites with smaller seasonal variation in water table depth (WTD). In contrast, WTD was the dominant predictor for wetlands with smaller variations in temperature (e.g., seasonal tropical/subtropical wetlands). Changes in seasonal FCH4 lagged fluctuations in WTD by ~17 ± 11 days, and lagged air and soil temperature by median values of 8 ± 16 and 5 ± 15 days, respectively. Temperature and WTD were also dominant predictors at the multiday scale. Atmospheric pressure (PA) was another important multiday scale predictor for peat-dominated sites, with drops in PA coinciding with synchronous releases of CH4 . At the diel scale, synchronous relationships with latent heat flux and vapor pressure deficit suggest that physical processes controlling evaporation and boundary layer mixing exert similar controls on CH4 volatilization, and suggest the influence of pressurized ventilation in aerenchymatous vegetation. In addition, 1- to 4-h lagged relationships with ecosystem photosynthesis indicate recent carbon substrates, such as root exudates, may also control FCH4. By addressing issues of scale, asynchrony, and nonlinearity, this work improves understanding of the predictors and timing of wetland FCH4 that can inform future studies and models, and help constrain wetland CH4 emissions.
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- 2021
14. Detecting vulnerability of humid tropical forests to multiple stressors
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Saatchi, Sassan, Longo, Marcos, Xu, Liang, Yang, Yan, Abe, Hitofumi, André, Michel, Aukema, Juliann E, Carvalhais, Nuno, Cadillo-Quiroz, Hinsby, Cerbu, Gillian Ann, Chernela, Janet M, Covey, Kristofer, Sánchez-Clavijo, Lina María, Cubillos, Isai V, Davies, Stuart J, De Sy, Veronique, De Vleeschouwer, Francois, Duque, Alvaro, Durieux, Alice Marie Sybille, De Avila Fernandes, Kátia, Fernandez, Luis E, Gammino, Victoria, Garrity, Dennis P, Gibbs, David A, Gibbon, Lucy, Gowae, Gae Yansom, Hansen, Matthew, Harris, Nancy Lee, Healey, Sean P, Hilton, Robert G, Johnson, Christine May, Kankeu, Richard Sufo, Laporte-Goetz, Nadine Therese, Lee, Hyongki, Lovejoy, Thomas, Lowman, Margaret, Lumbuenamo, Raymond, Malhi, Yadvinder, Martinez, Jean-Michel M Albert, Nobre, Carlos, Pellegrini, Adam, Radachowsky, Jeremy, Román, Francisco, Russell, Diane, Sheil, Douglas, Smith, Thomas B, Spencer, Robert GM, Stolle, Fred, Tata, Hesti Lestari, del Castillo Torres, Dennis, Tshimanga, Raphael Muamba, Vargas, Rodrigo, Venter, Michelle, West, Joshua, Widayati, Atiek, Wilson, Sylvia N, Brumby, Steven, and Elmore, Aurora C
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Life on Land ,Climate Action - Abstract
Humid tropical forests play a dominant role in the functioning of Earth but are under increasing threat from changes in land use and climate. How forest vulnerability varies across space and time and what level of stress forests can tolerate before facing a tipping point are poorly understood. Here, we develop a tropical forest vulnerability index (TFVI) to detect and evaluate the vulnerability of global tropical forests to threats across space and time. We show that climate change together with land-use change have slowed the recovery rate of forest carbon cycling. Temporal autocorrelation, as an indicator of this slow recovery, increases substantially for above-ground biomass, gross primary production, and evapotranspiration when climate stress reaches a critical level. Forests in the Americas exhibit extensive vulnerability to these stressors, while in Africa, forests show relative resilience to climate, and in Asia reveal more vulnerability to land use and fragmentation. TFVI can systematically track the response of tropical forests to multiple stressors and provide early-warning signals for regions undergoing critical transitions.
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- 2021
15. Representativeness of Eddy-Covariance flux footprints for areas surrounding AmeriFlux sites
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Chu, Housen, Luo, Xiangzhong, Ouyang, Zutao, Chan, W Stephen, Dengel, Sigrid, Biraud, Sébastien C, Torn, Margaret S, Metzger, Stefan, Kumar, Jitendra, Arain, M Altaf, Arkebauer, Tim J, Baldocchi, Dennis, Bernacchi, Carl, Billesbach, Dave, Black, T Andrew, Blanken, Peter D, Bohrer, Gil, Bracho, Rosvel, Brown, Shannon, Brunsell, Nathaniel A, Chen, Jiquan, Chen, Xingyuan, Clark, Kenneth, Desai, Ankur R, Duman, Tomer, Durden, David, Fares, Silvano, Forbrich, Inke, Gamon, John A, Gough, Christopher M, Griffis, Timothy, Helbig, Manuel, Hollinger, David, Humphreys, Elyn, Ikawa, Hiroki, Iwata, Hiroki, Ju, Yang, Knowles, John F, Knox, Sara H, Kobayashi, Hideki, Kolb, Thomas, Law, Beverly, Lee, Xuhui, Litvak, Marcy, Liu, Heping, Munger, J William, Noormets, Asko, Novick, Kim, Oberbauer, Steven F, Oechel, Walter, Oikawa, Patty, Papuga, Shirley A, Pendall, Elise, Prajapati, Prajaya, Prueger, John, Quinton, William L, Richardson, Andrew D, Russell, Eric S, Scott, Russell L, Starr, Gregory, Staebler, Ralf, Stoy, Paul C, Stuart-Haëntjens, Ellen, Sonnentag, Oliver, Sullivan, Ryan C, Suyker, Andy, Ueyama, Masahito, Vargas, Rodrigo, Wood, Jeffrey D, and Zona, Donatella
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Earth Sciences ,Flux footprint ,Spatial representativeness ,Landsat EVI ,Land cover ,Sensor location bias ,Model-data benchmarking ,Biological Sciences ,Agricultural and Veterinary Sciences ,Meteorology & Atmospheric Sciences ,Agricultural ,veterinary and food sciences ,Biological sciences ,Earth sciences - Abstract
Large datasets of greenhouse gas and energy surface-atmosphere fluxes measured with the eddy-covariance technique (e.g., FLUXNET2015, AmeriFlux BASE) are widely used to benchmark models and remote-sensing products. This study addresses one of the major challenges facing model-data integration: To what spatial extent do flux measurements taken at individual eddy-covariance sites reflect model- or satellite-based grid cells? We evaluate flux footprints—the temporally dynamic source areas that contribute to measured fluxes—and the representativeness of these footprints for target areas (e.g., within 250–3000 m radii around flux towers) that are often used in flux-data synthesis and modeling studies. We examine the land-cover composition and vegetation characteristics, represented here by the Enhanced Vegetation Index (EVI), in the flux footprints and target areas across 214 AmeriFlux sites, and evaluate potential biases as a consequence of the footprint-to-target-area mismatch. Monthly 80% footprint climatologies vary across sites and through time ranging four orders of magnitude from 103 to 107 m2 due to the measurement heights, underlying vegetation- and ground-surface characteristics, wind directions, and turbulent state of the atmosphere. Few eddy-covariance sites are located in a truly homogeneous landscape. Thus, the common model-data integration approaches that use a fixed-extent target area across sites introduce biases on the order of 4%–20% for EVI and 6%–20% for the dominant land cover percentage. These biases are site-specific functions of measurement heights, target area extents, and land-surface characteristics. We advocate that flux datasets need to be used with footprint awareness, especially in research and applications that benchmark against models and data products with explicit spatial information. We propose a simple representativeness index based on our evaluations that can be used as a guide to identify site-periods suitable for specific applications and to provide general guidance for data use.
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- 2021
16. Substantial hysteresis in emergent temperature sensitivity of global wetland CH4 emissions.
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Chang, Kuang-Yu, Riley, William J, Knox, Sara H, Jackson, Robert B, McNicol, Gavin, Poulter, Benjamin, Aurela, Mika, Baldocchi, Dennis, Bansal, Sheel, Bohrer, Gil, Campbell, David I, Cescatti, Alessandro, Chu, Housen, Delwiche, Kyle B, Desai, Ankur R, Euskirchen, Eugenie, Friborg, Thomas, Goeckede, Mathias, Helbig, Manuel, Hemes, Kyle S, Hirano, Takashi, Iwata, Hiroki, Kang, Minseok, Keenan, Trevor, Krauss, Ken W, Lohila, Annalea, Mammarella, Ivan, Mitra, Bhaskar, Miyata, Akira, Nilsson, Mats B, Noormets, Asko, Oechel, Walter C, Papale, Dario, Peichl, Matthias, Reba, Michele L, Rinne, Janne, Runkle, Benjamin RK, Ryu, Youngryel, Sachs, Torsten, Schäfer, Karina VR, Schmid, Hans Peter, Shurpali, Narasinha, Sonnentag, Oliver, Tang, Angela CI, Torn, Margaret S, Trotta, Carlo, Tuittila, Eeva-Stiina, Ueyama, Masahito, Vargas, Rodrigo, Vesala, Timo, Windham-Myers, Lisamarie, Zhang, Zhen, and Zona, Donatella
- Abstract
Wetland methane (CH4) emissions ([Formula: see text]) are important in global carbon budgets and climate change assessments. Currently, [Formula: see text] projections rely on prescribed static temperature sensitivity that varies among biogeochemical models. Meta-analyses have proposed a consistent [Formula: see text] temperature dependence across spatial scales for use in models; however, site-level studies demonstrate that [Formula: see text] are often controlled by factors beyond temperature. Here, we evaluate the relationship between [Formula: see text] and temperature using observations from the FLUXNET-CH4 database. Measurements collected across the globe show substantial seasonal hysteresis between [Formula: see text] and temperature, suggesting larger [Formula: see text] sensitivity to temperature later in the frost-free season (about 77% of site-years). Results derived from a machine-learning model and several regression models highlight the importance of representing the large spatial and temporal variability within site-years and ecosystem types. Mechanistic advancements in biogeochemical model parameterization and detailed measurements in factors modulating CH4 production are thus needed to improve global CH4 budget assessments.
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- 2021
17. Schwarzian derivatives for pluriharmonic mappings
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Efraimidis, Iason, Ferrada-Salas, Álvaro, Hernández, Rodrigo, and Vargas, Rodrigo
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Mathematics - Complex Variables ,30C99, 30G30, 31C10, 32A30, 32U05 - Abstract
A pre-Schwarzian and a Schwarzian derivative for locally univalent pluriharmonic mappings in ${\mathbb C}^n$ are introduced. Basic properties such as the chain rule, multiplicative invariance and affine invariance are proved for these operators. It is shown that the pre-Schwarzian is stable only with respect to rotations of the identity. A characterization is given for the case when the pre-Schwarzian derivative is holomorphic. Furthermore, it is shown that if the Schwarzian derivative of a pluriharmonic mapping vanishes then the analytic part of this mapping is a M\"obius transformation. Some observations are made related to the dilatation of pluriharmonic mappings and to the dilatation of their affine transformations, revealing differences between the theories in the plane and in higher dimensions. An example is given that rules out the possibility for a shear construction theorem to hold in ${\mathbb C}^n$, for $n\geq2$., Comment: 24 pages; to appear in Journal of Mathematical Analysis and Applications
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- 2019
18. Proximal remote sensing and gross primary productivity in a temperate salt marsh
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Vázquez-Lule, Alma and Vargas, Rodrigo
- Published
- 2023
- Full Text
- View/download PDF
19. FLUXNET-CH4: a global, multi-ecosystem dataset and analysis of methane seasonality from freshwater wetlands
- Author
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Delwiche, Kyle B, Knox, Sara Helen, Malhotra, Avni, Fluet-Chouinard, Etienne, McNicol, Gavin, Feron, Sarah, Ouyang, Zutao, Papale, Dario, Trotta, Carlo, Canfora, Eleonora, Cheah, You-Wei, Christianson, Danielle, Alberto, Ma Carmelita R, Alekseychik, Pavel, Aurela, Mika, Baldocchi, Dennis, Bansal, Sheel, Billesbach, David P, Bohrer, Gil, Bracho, Rosvel, Buchmann, Nina, Campbell, David I, Celis, Gerardo, Chen, Jiquan, Chen, Weinan, Chu, Housen, Dalmagro, Higo J, Dengel, Sigrid, Desai, Ankur R, Detto, Matteo, Dolman, Han, Eichelmann, Elke, Euskirchen, Eugenie, Famulari, Daniela, Fuchs, Kathrin, Goeckede, Mathias, Gogo, Sébastien, Gondwe, Mangaliso J, Goodrich, Jordan P, Gottschalk, Pia, Graham, Scott L, Heimann, Martin, Helbig, Manuel, Helfter, Carole, Hemes, Kyle S, Hirano, Takashi, Hollinger, David, Hörtnagl, Lukas, Iwata, Hiroki, Jacotot, Adrien, Jurasinski, Gerald, Kang, Minseok, Kasak, Kuno, King, John, Klatt, Janina, Koebsch, Franziska, Krauss, Ken W, Lai, Derrick YF, Lohila, Annalea, Mammarella, Ivan, Marchesini, Luca Belelli, Manca, Giovanni, Matthes, Jaclyn Hatala, Maximov, Trofim, Merbold, Lutz, Mitra, Bhaskar, Morin, Timothy H, Nemitz, Eiko, Nilsson, Mats B, Niu, Shuli, Oechel, Walter C, Oikawa, Patricia Y, Ono, Keisuke, Peichl, Matthias, Peltola, Olli, Reba, Michele L, Richardson, Andrew D, Riley, William, Runkle, Benjamin RK, Ryu, Youngryel, Sachs, Torsten, Sakabe, Ayaka, Sanchez, Camilo Rey, Schuur, Edward A, Schäfer, Karina VR, Sonnentag, Oliver, Sparks, Jed P, Stuart-Haëntjens, Ellen, Sturtevant, Cove, Sullivan, Ryan C, Szutu, Daphne J, Thom, Jonathan E, Torn, Margaret S, Tuittila, Eeva-Stiina, Turner, Jessica, Ueyama, Masahito, Valach, Alex C, Vargas, Rodrigo, Varlagin, Andrej, and Vazquez-Lule, Alma
- Subjects
Earth Sciences ,Atmospheric Sciences ,Climate Action ,Geochemistry ,Physical Geography and Environmental Geoscience ,Atmospheric sciences ,Geoinformatics ,Physical geography and environmental geoscience - Abstract
Methane (CH4) emissions from natural landscapes constitute roughly half of global CH4 contributions to the atmosphere, yet large uncertainties remain in the absolute magnitude and the seasonality of emission quantities and drivers. Eddy covariance (EC) measurements of CH4 flux are ideal for constraining ecosystem-scale CH4 emissions due to quasi-continuous and high-temporal-resolution CH4 flux measurements, coincident carbon dioxide, water, and energy flux measurements, lack of ecosystem disturbance, and increased availability of datasets over the last decade. Here, we (1) describe the newly published dataset, FLUXNET-CH4 Version 1.0, the first open-source global dataset of CH4 EC measurements (available at https://fluxnet.org/data/fluxnet-ch4-community-product/, last access: 7 April 2021). FLUXNET-CH4 includes half-hourly and daily gap-filled and non-gap-filled aggregated CH4 fluxes and meteorological data from 79 sites globally: 42 freshwater wetlands, 6 brackish and saline wetlands, 7 formerly drained ecosystems, 7 rice paddy sites, 2 lakes, and 15 uplands. Then, we (2) evaluate FLUXNET-CH4 representativeness for freshwater wetland coverage globally because the majority of sites in FLUXNET-CH4 Version 1.0 are freshwater wetlands which are a substantial source of total atmospheric CH4 emissions; and (3) we provide the first global estimates of the seasonal variability and seasonality predictors of freshwater wetland CH4 fluxes. Our representativeness analysis suggests that the freshwater wetland sites in the dataset cover global wetland bioclimatic attributes (encompassing energy, moisture, and vegetation-related parameters) in arctic, boreal, and temperate regions but only sparsely cover humid tropical regions. Seasonality metrics of wetland CH4 emissions vary considerably across latitudinal bands. In freshwater wetlands (except those between 20g g€¯S to 20g g€¯N) the spring onset of elevated CH4 emissions starts 3g€¯d earlier, and the CH4 emission season lasts 4g€¯d longer, for each degree Celsius increase in mean annual air temperature. On average, the spring onset of increasing CH4 emissions lags behind soil warming by 1 month, with very few sites experiencing increased CH4 emissions prior to the onset of soil warming. In contrast, roughly half of these sites experience the spring onset of rising CH4 emissions prior to the spring increase in gross primary productivity (GPP). The timing of peak summer CH4 emissions does not correlate with the timing for either peak summer temperature or peak GPP. Our results provide seasonality parameters for CH4 modeling and highlight seasonality metrics that cannot be predicted by temperature or GPP (i.e., seasonality of CH4 peak). FLUXNET-CH4 is a powerful new resource for diagnosing and understanding the role of terrestrial ecosystems and climate drivers in the global CH4 cycle, and future additions of sites in tropical ecosystems and site years of data collection will provide added value to this database. All seasonality parameters are available at 10.5281/zenodo.4672601 (Delwiche et al., 2021). Additionally, raw FLUXNET-CH4 data used to extract seasonality parameters can be downloaded from https://fluxnet.org/data/fluxnet-ch4-community-product/ (last access: 7 April 2021), and a complete list of the 79 individual site data DOIs is provided in Table 2 of this paper.
- Published
- 2021
20. COSORE: A community database for continuous soil respiration and other soil‐atmosphere greenhouse gas flux data
- Author
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Bond‐Lamberty, Ben, Christianson, Danielle S, Malhotra, Avni, Pennington, Stephanie C, Sihi, Debjani, AghaKouchak, Amir, Anjileli, Hassan, Arain, M Altaf, Armesto, Juan J, Ashraf, Samaneh, Ataka, Mioko, Baldocchi, Dennis, Black, Thomas Andrew, Buchmann, Nina, Carbone, Mariah S, Chang, Shih‐Chieh, Crill, Patrick, Curtis, Peter S, Davidson, Eric A, Desai, Ankur R, Drake, John E, El‐Madany, Tarek S, Gavazzi, Michael, Görres, Carolyn‐Monika, Gough, Christopher M, Goulden, Michael, Gregg, Jillian, del Arroyo, Omar Gutiérrez, He, Jin‐Sheng, Hirano, Takashi, Hopple, Anya, Hughes, Holly, Järveoja, Järvi, Jassal, Rachhpal, Jian, Jinshi, Kan, Haiming, Kaye, Jason, Kominami, Yuji, Liang, Naishen, Lipson, David, Macdonald, Catriona A, Maseyk, Kadmiel, Mathes, Kayla, Mauritz, Marguerite, Mayes, Melanie A, McNulty, Steve, Miao, Guofang, Migliavacca, Mirco, Miller, Scott, Miniat, Chelcy F, Nietz, Jennifer G, Nilsson, Mats B, Noormets, Asko, Norouzi, Hamidreza, O’Connell, Christine S, Osborne, Bruce, Oyonarte, Cecilio, Pang, Zhuo, Peichl, Matthias, Pendall, Elise, Perez‐Quezada, Jorge F, Phillips, Claire L, Phillips, Richard P, Raich, James W, Renchon, Alexandre A, Ruehr, Nadine K, Sánchez‐Cañete, Enrique P, Saunders, Matthew, Savage, Kathleen E, Schrumpf, Marion, Scott, Russell L, Seibt, Ulli, Silver, Whendee L, Sun, Wu, Szutu, Daphne, Takagi, Kentaro, Takagi, Masahiro, Teramoto, Munemasa, Tjoelker, Mark G, Trumbore, Susan, Ueyama, Masahito, Vargas, Rodrigo, Varner, Ruth K, Verfaillie, Joseph, Vogel, Christoph, Wang, Jinsong, Winston, Greg, Wood, Tana E, Wu, Juying, Wutzler, Thomas, Zeng, Jiye, Zha, Tianshan, Zhang, Quan, and Zou, Junliang
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Climate Change Impacts and Adaptation ,Environmental Sciences ,Climate Action ,Atmosphere ,Carbon Dioxide ,Ecosystem ,Greenhouse Gases ,Methane ,Nitrous Oxide ,Reproducibility of Results ,Respiration ,Soil ,carbon dioxide ,greenhouse gases ,methane ,open data ,open science ,soil respiration ,Biological Sciences ,Ecology ,Biological sciences ,Earth sciences ,Environmental sciences - Abstract
Globally, soils store two to three times as much carbon as currently resides in the atmosphere, and it is critical to understand how soil greenhouse gas (GHG) emissions and uptake will respond to ongoing climate change. In particular, the soil-to-atmosphere CO2 flux, commonly though imprecisely termed soil respiration (RS ), is one of the largest carbon fluxes in the Earth system. An increasing number of high-frequency RS measurements (typically, from an automated system with hourly sampling) have been made over the last two decades; an increasing number of methane measurements are being made with such systems as well. Such high frequency data are an invaluable resource for understanding GHG fluxes, but lack a central database or repository. Here we describe the lightweight, open-source COSORE (COntinuous SOil REspiration) database and software, that focuses on automated, continuous and long-term GHG flux datasets, and is intended to serve as a community resource for earth sciences, climate change syntheses and model evaluation. Contributed datasets are mapped to a single, consistent standard, with metadata on contributors, geographic location, measurement conditions and ancillary data. The design emphasizes the importance of reproducibility, scientific transparency and open access to data. While being oriented towards continuously measured RS , the database design accommodates other soil-atmosphere measurements (e.g. ecosystem respiration, chamber-measured net ecosystem exchange, methane fluxes) as well as experimental treatments (heterotrophic only, etc.). We give brief examples of the types of analyses possible using this new community resource and describe its accompanying R software package.
- Published
- 2020
21. SOMOSPIE: A modular SOil MOisture SPatial Inference Engine based on data driven decisions
- Author
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Rorabaugh, Danny, Guevara, Mario, Llamas, Ricardo, Kitson, Joy, Vargas, Rodrigo, and Taufer, Michela
- Subjects
Computer Science - Machine Learning - Abstract
The current availability of soil moisture data over large areas comes from satellite remote sensing technologies (i.e., radar-based systems), but these data have coarse resolution and often exhibit large spatial information gaps. Where data are too coarse or sparse for a given need (e.g., precision agriculture), one can leverage machine-learning techniques coupled with other sources of environmental information (e.g., topography) to generate gap-free information and at a finer spatial resolution (i.e., increased granularity). To this end, we develop a spatial inference engine consisting of modular stages for processing spatial environmental data, generating predictions with machine-learning techniques, and analyzing these predictions. We demonstrate the functionality of this approach and the effects of data processing choices via multiple prediction maps over a United States ecological region with a highly diverse soil moisture profile (i.e., the Middle Atlantic Coastal Plains). The relevance of our work derives from a pressing need to improve the spatial representation of soil moisture for applications in environmental sciences (e.g., ecological niche modeling, carbon monitoring systems, and other Earth system models) and precision agriculture (e.g., optimizing irrigation practices and other land management decisions)., Comment: 10 pages, 11 figures, 1 table
- Published
- 2019
22. Protein-caloric restriction induced HPA axis activation and altered the milk composition imprint metabolism of weaned rat offspring
- Author
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Martins, Isabela Peixoto, Vargas, Rodrigo, Saavedra, Lucas Paulo Jacinto, Rickli, Sarah, Matiusso, Camila Cristina Ianoni, Pavanello, Audrei, Casagrande, Lucas, Pastre, Maria José, Oliveira, Júlia Berno, de Almeida, Ariadny Martins, de Souza, Anna Carolina Huppes, de Oliveira, Júlio Cezar, Malta, Ananda, and Mathias, Paulo Cezar de Freitas
- Published
- 2023
- Full Text
- View/download PDF
23. Analysis of microbiota-host communication mediated by butyrate in Atlantic salmon
- Author
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Vargas, Rodrigo A., Soto-Aguilera, Sarita, Parra, Mick, Herrera, Sebastian, Santibañez, Alvaro, Kossack, Camila, Saavedra, Claudia P., Mora, Oscar, Pineda, Mauricio, Gonzalez, Oscar, Gonzalez, Alex, Maisey, Kevin, Torres-Maravilla, Edgar, Bermúdez-Humarán, Luis G., Suárez-Villota, Elkin Y., and Tello, Mario
- Published
- 2023
- Full Text
- View/download PDF
24. Ecosystem-atmosphere CO2 exchange from semiarid mangroves in the Gulf of California
- Author
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Vargas-Terminel, Martha L., Rodríguez, Julio C., Yépez, Enrico A., Robles-Zazueta, Carlos A., Watts, Christopher, Garatuza-Payán, Jaime, Vargas, Rodrigo, and Sanchez-Mejia, Zulia M.
- Published
- 2023
- Full Text
- View/download PDF
25. Oral administration of a new copper (I) complex with coumarin as ligand: modulation of the immune response and the composition of the intestinal microbiota in Onchorhynchus mykiss
- Author
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Parra, Mick, primary, Aldabaldetrecu, Maialen, additional, Arce, Pablo, additional, Soto-Aguilera, Sarita, additional, Vargas, Rodrigo, additional, Guerrero, Juan, additional, Tello, Mario, additional, and Modak, Brenda, additional
- Published
- 2024
- Full Text
- View/download PDF
26. [Cu(NN1)2]ClO4, a Copper (I) Complex as an Antimicrobial Agent for the Treatment of Piscirickettsiosis in Atlantic Salmon
- Author
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Parra, Mick, primary, Aldabaldetrecu, Maialen, additional, Arce, Pablo, additional, Soto-Aguilera, Sarita, additional, Vargas, Rodrigo, additional, Guerrero, Juan, additional, Tello, Mario, additional, and Modak, Brenda, additional
- Published
- 2024
- Full Text
- View/download PDF
27. Historically inconsistent productivity and respiration fluxes in the global terrestrial carbon cycle
- Author
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Jian, Jinshi, Bailey, Vanessa, Dorheim, Kalyn, Konings, Alexandra G., Hao, Dalei, Shiklomanov, Alexey N., Snyder, Abigail, Steele, Meredith, Teramoto, Munemasa, Vargas, Rodrigo, and Bond-Lamberty, Ben
- Published
- 2022
- Full Text
- View/download PDF
28. FLUXNET-CH4 Synthesis Activity: Objectives, Observations, and Future Directions FLUXNET-CH4 Synthesis Activity: Objectives, Observations, and Future Directions
- Author
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Knox, Sara H, Jackson, Robert B, Poulter, Benjamin, McNicol, Gavin, Fluet-Chouinard, Etienne, Zhang, Zhen, Hugelius, Gustaf, Bousquet, Philippe, Canadell, Josep G, Saunois, Marielle, Papale, Dario, Chu, Housen, Keenan, Trevor F, Baldocchi, Dennis, Torn, Margaret S, Mammarella, Ivan, Trotta, Carlo, Aurela, Mika, Bohrer, Gil, Campbell, David I, Cescatti, Alessandro, Chamberlain, Samuel, Chen, Jiquan, Chen, Weinan, Dengel, Sigrid, Desai, Ankur R, Euskirchen, Eugenie, Friborg, Thomas, Gasbarra, Daniele, Goded, Ignacio, Goeckede, Mathias, Heimann, Martin, Helbig, Manuel, Hirano, Takashi, Hollinger, David Y, Iwata, Hiroki, Kang, Minseok, Klatt, Janina, Krauss, Ken W, Kutzbach, Lars, Lohila, Annalea, Mitra, Bhaskar, Morin, Timothy H, Nilsson, Mats B, Niu, Shuli, Noormets, Asko, Oechel, Walter C, Peichl, Matthias, Peltola, Olli, Reba, Michele L, Richardson, Andrew D, Runkle, Benjamin RK, Ryu, Youngryel, Sachs, Torsten, Schäfer, Karina VR, Schmid, Hans Peter, Shurpali, Narasinha, Sonnentag, Oliver, Tang, Angela CI, Ueyama, Masahito, Vargas, Rodrigo, Vesala, Timo, Ward, Eric J, Windham-Myers, Lisamarie, Wohlfahrt, Georg, and Zona, Donatella
- Subjects
Earth Sciences ,Atmospheric Sciences ,Climate Change Science ,Astronomical and Space Sciences ,Physical Geography and Environmental Geoscience ,Meteorology & Atmospheric Sciences ,Atmospheric sciences ,Climate change science - Abstract
We describe a new coordination activity and initial results for a global synthesis of eddy covariance CH4 flux measurements.
- Published
- 2019
29. The value of soil respiration measurements for interpreting and modeling terrestrial carbon cycling
- Author
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Phillips, Claire L., Bond-Lamberty, Ben, Desai, Ankur R., Lavoie, Martin, Risk, Dave, Tang, Jianwu, Todd-Brown, Katherine, and Vargas, Rodrigo
- Published
- 2017
30. Iterative near-term ecological forecasting: Needs, opportunities, and challenges
- Author
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Dietze, Michael C, Fox, Andrew, Beck-Johnson, Lindsay M, Betancourt, Julio L, Hooten, Mevin B, Jarnevich, Catherine S, Keitt, Timothy H, Kenney, Melissa A, Laney, Christine M, Larsen, Laurel G, Loescher, Henry W, Lunch, Claire K, Pijanowski, Bryan C, Randerson, James T, Read, Emily K, Tredennick, Andrew T, Vargas, Rodrigo, Weathers, Kathleen C, and White, Ethan P
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Bayes Theorem ,Climate Change ,Ecology ,Ecosystem ,Forecasting ,Humans ,Models ,Theoretical ,forecast ,ecology ,prediction - Abstract
Two foundational questions about sustainability are "How are ecosystems and the services they provide going to change in the future?" and "How do human decisions affect these trajectories?" Answering these questions requires an ability to forecast ecological processes. Unfortunately, most ecological forecasts focus on centennial-scale climate responses, therefore neither meeting the needs of near-term (daily to decadal) environmental decision-making nor allowing comparison of specific, quantitative predictions to new observational data, one of the strongest tests of scientific theory. Near-term forecasts provide the opportunity to iteratively cycle between performing analyses and updating predictions in light of new evidence. This iterative process of gaining feedback, building experience, and correcting models and methods is critical for improving forecasts. Iterative, near-term forecasting will accelerate ecological research, make it more relevant to society, and inform sustainable decision-making under high uncertainty and adaptive management. Here, we identify the immediate scientific and societal needs, opportunities, and challenges for iterative near-term ecological forecasting. Over the past decade, data volume, variety, and accessibility have greatly increased, but challenges remain in interoperability, latency, and uncertainty quantification. Similarly, ecologists have made considerable advances in applying computational, informatic, and statistical methods, but opportunities exist for improving forecast-specific theory, methods, and cyberinfrastructure. Effective forecasting will also require changes in scientific training, culture, and institutions. The need to start forecasting is now; the time for making ecology more predictive is here, and learning by doing is the fastest route to drive the science forward.
- Published
- 2018
31. Networking our science to characterize the state, vulnerabilities, and management opportunities of soil organic matter
- Author
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Harden, Jennifer W, Hugelius, Gustaf, Ahlström, Anders, Blankinship, Joseph C, Bond‐Lamberty, Ben, Lawrence, Corey R, Loisel, Julie, Malhotra, Avni, Jackson, Robert B, Ogle, Stephen, Phillips, Claire, Ryals, Rebecca, Todd‐Brown, Katherine, Vargas, Rodrigo, Vergara, Sintana E, Cotrufo, M Francesca, Keiluweit, Marco, Heckman, Katherine A, Crow, Susan E, Silver, Whendee L, DeLonge, Marcia, and Nave, Lucas E
- Subjects
Environmental Sciences ,Biological Sciences ,Environmental Management ,Soil Sciences ,Life on Land ,Agriculture ,Carbon ,Carbon Cycle ,Carbon Sequestration ,Climate ,Climate Change ,Databases ,Factual ,Ecosystem ,International Cooperation ,Models ,Theoretical ,Soil ,agricultural practices ,C cycling ,C sequestration ,global CO2 ,network ,soil ,soil carbon ,soil management ,Ecology ,Biological sciences ,Earth sciences ,Environmental sciences - Abstract
Soil organic matter (SOM) supports the Earth's ability to sustain terrestrial ecosystems, provide food and fiber, and retains the largest pool of actively cycling carbon. Over 75% of the soil organic carbon (SOC) in the top meter of soil is directly affected by human land use. Large land areas have lost SOC as a result of land use practices, yet there are compensatory opportunities to enhance productivity and SOC storage in degraded lands through improved management practices. Large areas with and without intentional management are also being subjected to rapid changes in climate, making many SOC stocks vulnerable to losses by decomposition or disturbance. In order to quantify potential SOC losses or sequestration at field, regional, and global scales, measurements for detecting changes in SOC are needed. Such measurements and soil-management best practices should be based on well established and emerging scientific understanding of processes of C stabilization and destabilization over various timescales, soil types, and spatial scales. As newly engaged members of the International Soil Carbon Network, we have identified gaps in data, modeling, and communication that underscore the need for an open, shared network to frame and guide the study of SOM and SOC and their management for sustained production and climate regulation.
- Published
- 2018
32. Downscaling satellite soil moisture for landscape applications: A case study in Delaware, USA
- Author
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Warner, Daniel L., Guevara, Mario, Callahan, John, and Vargas, Rodrigo
- Published
- 2021
- Full Text
- View/download PDF
33. Empirical Dynamic Modeling Reveals Complexity of Methane Fluxes in a Temperate Salt Marsh
- Author
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Hill, Andrew C., primary, Schäfer, Karina V. R., additional, Forbrich, Inke, additional, and Vargas, Rodrigo, additional
- Published
- 2024
- Full Text
- View/download PDF
34. What fire didn’t take away: plant growth-promoting microorganisms await for plant species' arrival in burned old-growth forests of Los Andes Cordillera.
- Author
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Almonacid, Leonardo, primary, HERRERA, HECTOR, additional, FUENTES, ANDRES, additional, VARGAS, RODRIGO, additional, TOY, OCTAVIO, additional, VALADARES, RAFAEL, additional, and DE OLIVEIRA, PAULO, additional
- Published
- 2024
- Full Text
- View/download PDF
35. A Greenhouse Gas Budget for Mexico During 2000–2019
- Author
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Murray‐Tortarolo, Guillermo, primary, Perea, Kevin, additional, Mendoza‐Ponce, Alma, additional, Martínez‐Arroyo, Amparo, additional, Murguía‐Flores, Fabiola, additional, Jaramillo, Víctor J., additional, Serrano‐Medrano, Montserrat, additional, García‐García, Miguel, additional, Vargas, Rodrigo, additional, Chatterjee, Abhishek, additional, Michalak, Anna, additional, Zhang, Zhen, additional, Wang, Jonathan A., additional, and Poulter, Benjamin, additional
- Published
- 2024
- Full Text
- View/download PDF
36. Linking vegetation spectral reflectance with ecosystem carbon phenology in a temperate salt marsh
- Author
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Hill, Andrew C., Vázquez-Lule, Alma, and Vargas, Rodrigo
- Published
- 2021
- Full Text
- View/download PDF
37. Visible and near-infrared hyperspectral indices explain more variation in lower-crown leaf nitrogen concentrations in autumn than in summer
- Author
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Wheeler, Kathryn I., Levia, Delphis F., and Vargas, Rodrigo
- Published
- 2020
38. Biophysical drivers of net ecosystem and methane exchange across phenological phases in a tidal salt marsh
- Author
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Vázquez-Lule, Alma and Vargas, Rodrigo
- Published
- 2021
- Full Text
- View/download PDF
39. Ethical Training as a School's Cross-Cutting Goal/Formacion ética como objetivo transversal de la escuela
- Author
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Lagos-Vargas, Rodrigo, Keupuchur-Natalini, Claudia, and Ramirez-Duran, Marcelo
- Published
- 2021
- Full Text
- View/download PDF
40. Carbon dioxide dynamics in a residential lawn of a tropical city
- Author
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Velasco, Erik, Segovia, Elvagris, Choong, Amy M.F., Lim, Benjamin K.Y., and Vargas, Rodrigo
- Published
- 2021
- Full Text
- View/download PDF
41. Patterns and drivers of multi-annual CO2 emissions within a temperate suburban neighborhood
- Author
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Hill, Andrew C., Barba, Josep, Hom, John, and Vargas, Rodrigo
- Published
- 2021
- Full Text
- View/download PDF
42. Gastric cancer actionable genomic alterations across diverse populations worldwide and pharmacogenomics strategies based on precision oncology.
- Author
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Echeverría-Garcés, Gabriela, Ramos-Medina, María José, Vargas, Rodrigo, Cabrera-Andrade, Alejandro, Altamirano-Colina, Adriana, Freire, María Paula, Montalvo-Guerrero, Juliana, Rivera-Orellana, Sebastián, Echeverría-Espinoza, Paulina, Quiñones, Luis A., and López-Cortés, Andrés
- Subjects
PHARMACOGENOMICS ,STOMACH cancer ,WHOLE genome sequencing ,CANCER genes ,ONCOLOGY ,DRUG prescribing ,PRECISION farming - Abstract
Introduction: Gastric cancer is one of the most prevalent types of cancer worldwide. The World Health Organization (WHO), the International Agency for Research on Cancer (IARC), and the Global Cancer Statistics (GLOBOCAN) reported an age standardized global incidence rate of 9.2 per 100,000 individuals for gastric cancer in 2022, with a mortality rate of 6.1. Despite considerable progress in precision oncology through the efforts of international consortia, understanding the genomic features and their influence on the effectiveness of anti-cancer treatments across diverse ethnic groups remains essential. Methods: Our study aimed to address this need by conducting integrated in silico analyses to identify actionable genomic alterations in gastric cancer driver genes, assess their impact using deleteriousness scores, and determine allele frequencies across nine global populations: European Finnish, European non-Finnish, Latino, East Asian, South Asian, African, Middle Eastern, Ashkenazi Jewish, and Amish. Furthermore, our goal was to prioritize targeted therapeutic strategies based on pharmacogenomics clinical guidelines, in silico drug prescriptions, and clinical trial data. Results: Our comprehensive analysis examined 275,634 variants within 60 gastric cancer driver genes from 730,947 exome sequences and 76,215 whole-genome sequences from unrelated individuals, identifying 13,542 annotated and predicted oncogenic variants. We prioritized the most prevalent and deleterious oncogenic variants for subsequent pharmacogenomics testing. Additionally, we discovered actionable genomic alterations in the ARID1A, ATM, BCOR, ERBB2, ERBB3, CDKN2A, KIT, PIK3CA, PTEN, NTRK3, TP53, and CDKN2A genes that could enhance the efficacy of anti-cancer therapies, as suggested by in silico drug prescription analyses, reviews of current pharmacogenomics clinical guidelines, and evaluations of phase III and IV clinical trials targeting gastric cancer driver proteins. Discussion: These findings underline the urgency of consolidating efforts to devise effective prevention measures, invest in genomic profiling for underrepresented populations, and ensure the inclusion of ethnic minorities in future clinical trials and cancer research in developed countries. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
43. [Cu(NN 1) 2 ]ClO 4 , a Copper (I) Complex as an Antimicrobial Agent for the Treatment of Piscirickettsiosis in Atlantic Salmon.
- Author
-
Parra, Mick, Aldabaldetrecu, Maialen, Arce, Pablo, Soto-Aguilera, Sarita, Vargas, Rodrigo, Guerrero, Juan, Tello, Mario, and Modak, Brenda
- Subjects
ATLANTIC salmon ,COPPER ,GUT microbiome ,ANTI-infective agents ,FISH growth ,SULFONAMIDE drugs - Abstract
Piscirickettsia salmonis is the pathogen that most affects the salmon industry in Chile. Large quantities of antibiotics have been used to control it. In search of alternatives, we have developed [Cu(NN
1 )2 ]ClO4 where NN1 = 6-((quinolin-2-ylmethylene)amino)-2H-chromen-2-one. The antibacterial capacity of [Cu(NN1 )2 ]ClO4 was determined. Subsequently, the effect of the administration of [Cu(NN1 )2 ]ClO4 on the growth of S. salar, modulation of the immune system and the intestinal microbiota was studied. Finally, the ability to protect against a challenge with P. salmonis was evaluated. The results obtained showed that the compound has an MIC between 15 and 33.9 μg/mL in four isolates. On the other hand, the compound did not affect the growth of the fish; however, an increase in the transcript levels of IFN-γ, IL-12, IL-1β, CD4, lysozyme and perforin was observed in fish treated with 40 μg/g of fish. Furthermore, modulation of the intestinal microbiota was observed, increasing the genera of beneficial bacteria such as Lactobacillus and Bacillus as well as potential pathogens such as Vibrio and Piscirickettsia. Finally, the treatment increased survival in fish challenged with P. salmonis by more than 60%. These results demonstrate that the compound is capable of protecting fish against P. salmonis, probably by modulating the immune system and the composition of the intestinal microbiota. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
44. Importance of Probiotics in Fish Aquaculture: Towards the Identification and Design of Novel Probiotics.
- Author
-
Torres-Maravilla, Edgar, Parra, Mick, Maisey, Kevin, Vargas, Rodrigo A., Cabezas-Cruz, Alejandro, Gonzalez, Alex, Tello, Mario, and Bermúdez-Humarán, Luis G.
- Subjects
FISH farming ,PROBIOTICS ,ANIMAL health ,AQUACULTURE industry ,FISH immunology ,IDENTIFICATION ,GENETICALLY modified foods - Abstract
Aquaculture is a growing industry worldwide, but it faces challenges related to animal health. These challenges include infections by parasites, bacteria, and viral pathogens. These harmful pathogens have devastating effects on the industry, despite efforts to control them through vaccination and antimicrobial treatments. Unfortunately, these measures have proven insufficient to address the sanitary problems, resulting in greater environmental impact due to the excessive use of antimicrobials. In recent years, probiotics have emerged as a promising solution to enhance the performance of the immune system against parasitic, bacterial, and viral pathogens in various species, including mammals, birds, and fish. Some probiotics have been genetically engineered to express and deliver immunomodulatory molecules. These promote selective therapeutic effects and specific immunization against specific pathogens. This review aims to summarize recent research on the use of probiotics in fish aquaculture, with a particular emphasis on genetically modified probiotics. In particular, we focus on the advantages of using these microorganisms and highlight the main barriers hindering their widespread application in the aquaculture industry. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
45. Spatial and temporal heterogeneity of geochemical controls on carbon cycling in a tidal salt marsh
- Author
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Seyfferth, Angelia L., Bothfeld, Frances, Vargas, Rodrigo, Stuckey, Jason W., Wang, Jian, Kearns, Kelli, Michael, Holly A., Guimond, Julia, Yu, Xuan, and Sparks, Donald L.
- Published
- 2020
- Full Text
- View/download PDF
46. Terrestrial carbon balance in a drier world: the effects of water availability in southwestern North America
- Author
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Biederman, Joel A, Scott, Russell L, Goulden, Michael L, Vargas, Rodrigo, Litvak, Marcy E, Kolb, Thomas E, Yepez, Enrico A, Oechel, Walter C, Blanken, Peter D, Bell, Tom W, Garatuza-Payan, Jaime, Maurer, Gregory E, Dore, Sabina, and Burns, Sean P
- Subjects
Plant Biology ,Biological Sciences ,Climate Action ,Carbon Cycle ,Carbon Dioxide ,Climate Change ,Desert Climate ,Droughts ,Mexico ,Photosynthesis ,Seasons ,Southwestern United States ,carbon dioxide ,climate ,ecosystem ,evapotranspiration ,net ecosystem exchange ,net ecosystem production ,photosynthesis ,productivity ,respiration ,semiarid ,water ,Environmental Sciences ,Ecology ,Biological sciences ,Earth sciences ,Environmental sciences - Abstract
Global modeling efforts indicate semiarid regions dominate the increasing trend and interannual variation of net CO2 exchange with the atmosphere, mainly driven by water availability. Many semiarid regions are expected to undergo climatic drying, but the impacts on net CO2 exchange are poorly understood due to limited semiarid flux observations. Here we evaluated 121 site-years of annual eddy covariance measurements of net and gross CO2 exchange (photosynthesis and respiration), precipitation, and evapotranspiration (ET) in 21 semiarid North American ecosystems with an observed range of 100 - 1000 mm in annual precipitation and records of 4-9 years each. In addition to evaluating spatial relationships among CO2 and water fluxes across sites, we separately quantified site-level temporal relationships, representing sensitivity to interannual variation. Across the climatic and ecological gradient, photosynthesis showed a saturating spatial relationship to precipitation, whereas the photosynthesis-ET relationship was linear, suggesting ET was a better proxy for water available to drive CO2 exchanges after hydrologic losses. Both photosynthesis and respiration showed similar site-level sensitivity to interannual changes in ET among the 21 ecosystems. Furthermore, these temporal relationships were not different from the spatial relationships of long-term mean CO2 exchanges with climatic ET. Consequently, a hypothetical 100-mm change in ET, whether short term or long term, was predicted to alter net ecosystem production (NEP) by 64 gCm(-2) yr(-1). Most of the unexplained NEP variability was related to persistent, site-specific function, suggesting prioritization of research on slow-changing controls. Common temporal and spatial sensitivity to water availability increases our confidence that site-level responses to interannual weather can be extrapolated for prediction of CO2 exchanges over decadal and longer timescales relevant to societal response to climate change.
- Published
- 2016
47. Management Impacts on Carbon Dynamics in a Sierra Nevada Mixed Conifer Forest.
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Dore, Sabina, Fry, Danny L, Collins, Brandon M, Vargas, Rodrigo, York, Robert A, and Stephens, Scott L
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Coniferophyta ,Carbon Dioxide ,Soil ,Fires ,Ecosystem ,Biomass ,Forestry ,California ,Carbon Cycle ,Forests ,General Science & Technology - Abstract
Forest ecosystems can act as sinks of carbon and thus mitigate anthropogenic carbon emissions. When forests are actively managed, treatments can alter forests carbon dynamics, reducing their sink strength and switching them from sinks to sources of carbon. These effects are generally characterized by fast temporal dynamics. Hence this study monitored for over a decade the impacts of management practices commonly used to reduce fire hazards on the carbon dynamics of mixed-conifer forests in the Sierra Nevada, California, USA. Soil CO2 efflux, carbon pools (i.e. soil carbon, litter, fine roots, tree biomass), and radial tree growth were compared among un-manipulated controls, prescribed fire, thinning, thinning followed by fire, and two clear-cut harvested sites. Soil CO2 efflux was reduced by both fire and harvesting (ca. 15%). Soil carbon content (upper 15 cm) was not significantly changed by harvest or fire treatments. Fine root biomass was reduced by clear-cut harvest (60-70%) but not by fire, and the litter layer was reduced 80% by clear-cut harvest and 40% by fire. Thinning effects on tree growth and biomass were concentrated in the first year after treatments, whereas fire effects persisted over the seven-year post-treatment period. Over this period, tree radial growth was increased (25%) by thinning and reduced (12%) by fire. After seven years, tree biomass returned to pre-treatment levels in both fire and thinning treatments; however, biomass and productivity decreased 30%-40% compared to controls when thinning was combined with fire. The clear-cut treatment had the strongest impact, reducing ecosystem carbon stocks and delaying the capacity for carbon uptake. We conclude that post-treatment carbon dynamics and ecosystem recovery time varied with intensity and type of treatments. Consequently, management practices can be selected to minimize ecosystem carbon losses while increasing future carbon uptake, resilience to high severity fire, and climate related stresses.
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- 2016
48. High methane concentrations in tidal salt marsh soils: Where does the methane go?
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Capooci, Margaret, primary, Seyfferth, Angelia L., additional, Tobias, Craig, additional, Wozniak, Andrew S., additional, Hedgpeth, Alexandra, additional, Bowen, Malique, additional, Biddle, Jennifer F., additional, McFarlane, Karis J., additional, and Vargas, Rodrigo, additional
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- 2023
- Full Text
- View/download PDF
49. Methane emissions from tree stems : a new frontier in the global carbon cycle
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Barba, Josep, Bradford, Mark A., Brewer, Paul E., Bruhn, Dan, Covey, Kristofer, van Haren, Joost, Megonigal, J. Patrick, Mikkelsen, Teis Nørgaard, Pangala, Sunitha R., Pihlatie, Mari, Poulter, Ben, Rivas-Ubach, Albert, Schadt, Christopher W., Terazawa, Kazuhiko, Warner, Daniel L., Zhang, Zhen, and Vargas, Rodrigo
- Published
- 2019
50. The impact of flooding on aquatic ecosystem services
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Talbot, Ceara J., Bennett, Elena M., Cassell, Kelsie, Hanes, Daniel M., Minor, Elizabeth C., Paerl, Hans, Raymond, Peter A., Vargas, Rodrigo, Vidon, Philippe G., Wollheim, Wilfred, and Xenopoulos, Marguerite A.
- Published
- 2018
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