With over 40 years of continuous data collection across many biomes, the Long Term Ecological Research (LTER) Network is a rich source of information for testing big-picture concepts about how ecosystems work. Luckily, the Network also brings together a group of scientists with creative ideas about how to wring new insights from diverse data sources.

The LTER synthesis working group process is designed to capitalize on the experiments, contextual knowledge, data, and creativity of the LTER Network. By funding small groups of scientists from inside and outside the Network to work intensely together on a synthesis project, the process encourages the ecological community to use existing data to probe novel theories, test generality, and search for gaps in our understanding.

The active Synthesis Working Groups are listed below.

For more about synthesis at the LTER, including our proposal process, see the synthesis homepage or follow the quick links below.

Current Working Groups

Marine consumer nutrient dynamics

fish swimming through kelp forest
Principal Investigator: Mackenzie White, Graduate Student, FIU, Bradley Strickland, Postdoctoral Research Associate, VIMS, Jennifer Rehage, Associate Professor, FIU, Deron Burkepile, Professor, UC Santa Barbara,
Award Date: January 10, 2023

Consumer-mediated nutrient dynamics of marine ecosystems under the wake of global change

Increases in the frequency and severity of disturbance events as a result of global change are altering population and community dynamics of marine animals. Given that animals are key recyclers of nutrients in many ecosystems, these ecological impacts may have consequences for ecosystem function. Consumer-mediated nutrient dynamics (CND) are an integral part of biogeochemical cycles, but to-date long-term studies are lacking. Without long-term data across large spatial scales, it is difficult to predict how ecosystems will respond to disturbances. The synthesis group plans to estimate CND over broad spatiotemporal scales by integrating empirical models of consumer nutrient excretion and egestion with time-series of consumer populations across ten marine and coastal LTER sites. They will address two main objectives:
  1. characterizing spatiotemporal patterns in the magnitude and variability of CND and;
  2. evaluating the resilience of CND to variable disturbance events.
This is a revised proposal based on positive feedback of the group's 2018 submission and input from colleagues during a cross-site workshop at the 2022 LTER ASM. With funds from LTER LNO, this diverse working group will synthesize LTER data to improve understanding of CND over broad spatiotemporal scales under the wake of global change.

Pelagic community structure

school of herring
Principal Investigator: Russell R Hopcroft, Professor, University of Alaska Fairbanks, rrhopcroft@alaska.edu, Mark Ohman, Professor, Scripps Institution of Oceanography, Heidi Sosik, Senior Scientist, Woods Hole Oceanographic Institution, Oscar Schofield, Professor, Rutgers University
Award Date: January 10, 2023

Interannual variability and long term change in pelagic community structure across a latitudinal gradient

Recent synthesis has shown both similarities and differences in how pelagic marine ecosystems have been influenced by cyclic and long term changes in the marine environment. The pelagic community structure synthesis group uses comparative data to test a series of conceptual models describing how communities respond to stochastic and long-term change along the latitudinal gradient represented by the four participating LTER sites. Their multipronged team approach employs two major lines of enquiry:

  1. examining whether patterns & processes discovered in the California Current Ecosystem (CCE) apply to other pelagic sites, and
  2. exploring whether recently proposed global pelagic community responses apply to the LTER sites, including how such responses are modulated by season and how they may have changed over decadal time frames.

The Flux Gradient Project

researcher recording data in flux tower overlooking coastal forest
Principal Investigator: Sparkle L. Malone, Assistant Professor, Yale University, Jackie H. Matthes, Senior Scientist, Harvard University
Award Date: January 10, 2023

The Flux Gradient Project: Understanding the methane sink-source capacity of natural ecosystems

While biogenic CH4 emissions are thought to be of a similar magnitude to anthropogenic emissions, biogenic emissions remain the most uncertain source of the global CH4 budget. The vast areas with relatively small uptake and emission rates have been largely understudied but could contribute significantly to regional and global budgets. Upland ecosystems can exhibit unexpectedly large annual CH4 fluxes and should not be excluded from observation networks. Yet, current eddy covariance towers measuring CH4 fluxes are biased toward wetlands, and other areas where we expect to observe large fluxes. To improve our understanding of biogenic fluxes, the Flux Gradient Project will utilize infrastructure from the National Ecological Observatory Network (NEON) at co-located LTER-NEON sites to calculate CH4 fluxes. In addition to the fluxes at co-located sites, we will also utilize CH4 fluxes from LTER, Ameriflux and Fluxnet sites. We hypothesize that upland ecosystems will fluctuate from being a sink to a source depending on moisture conditions. Quantifying the CH4 budget of natural ecosystems is important for assessing realistic pathways to mitigate climate change, because uncertainties in the magnitude, size, and location of sources and sinks are currently limiting budget development.


View all Working Groups