The interdisciplinary science of ecology is increasingly being challenged to predict future scenarios of biological structure and ecosystem function in the face of global environmental uncertainty. We have insufficient knowledge of the threshold responses of energy transformations in ecosystems that enable them to be resilient and persist. Carbon (energy) is a fundamental currency in ecology, and the relative rates of carbon turnover in ecosystems can influence the amount of consumer biomass supported. My research focuses on the dynamics of organic matter processing within and among ecosystems and how these are driven by nutrient biogeochemistry and consumer interactions to affect net ecosystem carbon retention. I make measurements and observations across multiple spatial and temporal scales, using experimental manipulations to isolate mechanisms. My research is informed by and informs basic ecological theory, and I integrate cross-ecosystem and long-term comparisons to enhance synthetic and broader understanding of ecological phenomena. I am able to maintain a high level of collaboration both nationally and internationally, acquire state and federal funding, publish in top-tier academic, peer-reviewed journals, and train students to be collaborative, rigorous, and professional scientists.
Our research explores various scales of organic matter processing along gradients of environmental drivers within and among ecosystems, testing two main questions:
- How do disturbances drive changes in autotrophic, heterotrophic, and net ecosystem productivity and carbon storage?
- How do disturbances interact with long-term environmental changes to affect ecosystem functions, specifically the loss, storage, and movement of carbon (energy) and nutrients within and among ecosystems?
Effects of saltwater intrusion on carbon retention in coastal ecosystems. Troxler, T.J. (PI), F. Sklar, E. E. Gaiser, J.S. Kominoski (Co-PI), S.E. Davis. National Oceanic & Atmospheric Administration, Florida Sea Grant. Mechanisms of peat collapse in Everglades coastal ecosystems: Phase II salinity manipulations and surface elevation change. (Kominoski: $279,216). Troxler, T.J. (PI), F. Sklar, E. E. Gaiser, J.S. Kominoski (Co-PI), S.E. Davis. The effects of projected sea-level rise on Everglades coastal ecosystems: Evaluating the potential for and mechanisms of peat collapse using integrated mesocosm and field manipulations. National Oceanic & Atmospheric Administration, Florida Sea Grant. (Total: $279,216; Kominoski: $279,216). April 2013-2015. I am co-leading a collaboration with colleagues at Everglades National Park, South Florida Water Management District, and the Everglades Foundation on a project funded by NOAA/Florida Sea Grant to understand the functional consequences of saltwater intrusion on plant, soil, and aquatic carbon loss in freshwater and brackish coastal wetland ecosystems. We currently have multiple long-term field and mesocosm experiments, and short-term laboratory experiments manipulating the concentrations of salinity and phosphorus contained in seawater to assess autotrophic and heterotrophic subsidy-stress responses and net effects on ecosystem carbon retention. This research is critical to forecasting sea-level rise impacts on structural and functional resilience in coastal ecosystems.
Effects of vegetation state changes on ecosystem carbon allocation and resilience. Kominoski, J.S. (PI), S. Charles (Co-PI). Dissertation Research: Sea level rise and vegetation regime shifts: implications for soil carbon storage and vulnerability in coastal wetlands. National Science Foundation, Division of Environmental Biology (Total: $16,380; Kominoski: $16,380). June 2016-2017. Regime shifts in foundation species due to global change are widespread and increasing, but rarely are studied experimentally at large spatial scales. Understanding how ecological regime shifts affect ecosystem resilience – the capacity to undergo change while maintaining similar structural and/or functional capacity – is paramount given current global environmental change. Through collaborations with Texas A&M University and the University of Houston, we have developed the first study to experimentally address the consequences of rapid and ongoing mangrove encroachment into salt marsh habitats. Our large spatial (ten 24 x 42 m plots) and temporal scale (2 years and ongoing) allows for an unprecedented ability to quantify the ecosystem impacts of this foundation species shift in a critical coastal habitat. We have identified thresholds and non-linearities in ecosystem responses to these changes (Guo et al. 2017).
Ecosystem metabolism and biogeochemical cycling as tools for ecosystem restoration. Gaiser, E.E. (PI), J.S. Kominoski (co-PI), L. Scinto, J.C. Trexler. Assessing near-field and landscape scale ecological effects of the Modified Water Deliveries and Comprehensive Everglades Restoration Plan projects in Northeast Shark River Slough, Everglades National Park. National Park Service, $448,523. October 2016-2021. Gaiser, E.E. (PI), R. Jaffe, M. Heithaus, J.S. Kominoski (Co-PI), and R. Price. FCE III: Coastal Oligotrophic Ecosystems Research. National Science Foundation. (Total: $5,880,000; Kominoski: $480,000). December 2012 – November 2018. Crowl, T. (PI), J.S. Kominoski (Senior Personnel). CREST: Center for Aquatic Chemistry & Environment (CAChE). National Science Foundation, Division of Education & Human Resources, (Total: $5,000,000). May 2016-2021. The Florida Everglades are the largest freshwater wetland landscape in North America, and one in three Floridians rely on it for municipal water. Current and continued efforts to restore freshwater flows to this vital and unique landscape provide us an opportunity to understand how seasonal variation in hydrology and organic matter transport influence whole ecosystem metabolism. Through collaborations with the South Florida Water Management District and Everglades National Park, I am continuously investigating the long-term effects of water quality (dissolved oxygen, temperature, nutrients) and organic matter transport dynamics to determine benchmarks of ecosystem function that could be met through the Comprehensive Everglades Restoration Plan. I am also collaborating with The Nature Conservancy on the Wagner Creek – Seybold Canal Restoration Project in Miami, FL, which is using a before-after-control-impact design (BACI) to assess how removal of contaminated sediment and implementation of green infrastructure can enhance ecosystem functioning (dissolved oxygen and metabolism).
Urban Resilience to Extremes. Gaiser, E.E. (PI), J.S. Kominoski, T.G. Troxler (Co-PI). Urban Resilience to Climate Change-Driven Extreme Events. National Science Foundation, Sustainability Research Networks (Total: $10,499,692; Kominoski: $614,921). July 2015-2020. I am collaborating with a large network of scientists and city practitioners from an international project assessing urban resilience to extreme events (excessive heat, coastal flooding, urban flooding, drought). Our network uses a social, ecological, and technological (SETs) framework to assess the relative vulnerability of urban systems that span gradients in climate, green and grey infrastructure, and extreme event risks. Miami is among the cities participating in this project, and we are actively assessing flood risk and flood mitigation strategies using a SETs framework and green infrastructure project.
SCALER: Scaling Consumers and Lotic Ecosystem Rates. Dodds, W.K. (PI), W.M. McDowell, W. Wollheim, A. Helton, B. Bowden, J. Jones, A.D. Rosemond, J.S. Kominoski, M.J. Whiles. M. Flynn, F. Ballentyne, T. Harms. National Science Foundation, Emerging Frontiers, Macrosystems Biology. Collaborative Research: Scaling Consumers and Lotic Ecosystem Rates (SCALER): Centimeters to Continents. (Total: $1,500,000; Kominoski: $262,697). October 2012 – 2017. We expanded the definition of the field of Macrosystems Biology (Heffernan et al. 2014) and identified the needs for and challenges of interdisciplinary collaboration (Goring et al. 2014). Then, we used cm- and reach-scale process measurements to predict ecosystem characteristics of stream networks (Rüegg et al. 2016). This collaborative, cross-site experiment integrated empirical tests and network-level, process-based modeling to understand how patterns of scaling compare across river network from an array of North American biomes (Farrell et al. 2018, Song et al. 2018).
Water Sustainability across the U.S. Sunbelt. Arumugam, S. (PI), E. Berglund, K. Gnanamanikam, K. Kunkel, T. Sinha, K.L. Larson, J.L. Sabo, J.S. Kominoski. National Science Foundation. Category 3: Collaborative Research: Water Sustainability under Near-term Climate Change: A cross-regional analysis incorporating socio-ecological feedbacks and adaptations. (Total: $1,300,000; Kominoski: $111,132). September 2012 – 2016. Through a collaboration with other ecologists, hydrologists, climatologists, and sociologists, we developed an interdisciplinary framework incorporating societal feedbacks and adaptations for freshwater sustainability under near-term change and human population growth (Arumugam et al. 2017). Downscaled streamflow projections linked mechanistically to fish communities were used as covariates, to provide estimates of reliability (persistence across the spectrum of flow extremes), resilience (adaptability to flow variation), vulnerability (extinction) and covariation between persistence and the effects of changes in magnitudes of low- and high-flow anomalies on native fish species (Kominoski et al. 2018). This research incorporated near-term climate change information in water infrastructure planning for the rapidly growing U.S. Sunbelt region with distinct climate and ecological characteristics and limitations.
Temperature-dependence of leaf litter breakdown in streams. Follstad Shah, J. (PI), M. Ardón, Kominoski, J.S. National Science Foundation, 2010 LTER Cross-site Synthesis Workshop Grant ($13,105). I co-led a global synthesis of leaf litter breakdown rates (kD, per day; kDD, per degree day) in streams and rivers, from 169 published studies, spanning absolute latitudes of 0° – 60°, to quantify the temperature dependence of leaf litter breakdown and examine how macroinvertebrate density and leaf quality affect it. Our results suggest that rates of leaf litter breakdown may increase by 11-16% with a 2-3 °C average global increase in water temperature, but the balance of microbial and metazoan contributions to leaf litter processing is unlikely to change (Follstad Shah et al. 2017).
Nutrient enrichment effects across trophic levels in aquatic ecosystems. Globally, many stream and river ecosystems have experienced increases in dissolved nitrogen (N) and phosphorus (P) from anthropogenic activities. Quantifying changes in biological processes due to higher nutrient availabilities has been a research priority of basic and applied ecologists. However, an integrated assessment of nutrient enrichment effects on food webs across aquatic ecosystem types and biomes is lacking. We conducted a meta-analysis of published studies that experimentally increased N or P concentrations in streams and rivers, with the expectations that (1) response magnitudes would be lower at higher trophic levels and (2) ambient stream characteristics would moderate response magnitudes across all trophic levels (microbial heterotroph, primary producer, primary consumer, secondary consumer, integrated ecosystem), with no significant difference among trophic levels (Ardón et al. 2021).
Assessing how saltwater intrusion effects carbon and nutrient biogeochemistry in coastal ecosystems.
Characterizing how long-term ecological research informs meta-community ecology theory.