With more than 37 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.
Principal Investigator: Eric Sokol, Christopher Swan, Nathan Wisnoski
Award Date: September 1, 2016
Description: What factors impact the stability of ecosystems? Previous research has identified dispersal, niche differentiation, and habitat heterogeneity as crucial parameters that determine metacommunity dynamics and stability in response to disturbance. Researchers do not know, however, whether these factors confer stability over long time scales or across ecosystem types. Using LTER datasets, the working group will assess how well these parameters estimate stability across time and space–and in the process, identify the major predictors of metacommunity stability.
Description: Soil organic matter is a massive storehouse for carbon, as well as a key regulator of nutrient cycling and soil quality in terrestrial ecosystems, yet ecology lacks a full understanding of the controls on stabilization and breakdown of soil organic matter. Two sets of competing theories underlie models that adequately predict site-specific dynamics, but result in different sets of predictions about the response of soil organic matter to perturbations.
Principal Investigator: Adam Wymore, Sujay Kaushal
Award Date: September 1, 2016
Description: The working group will compare stream chemistry data from 19 sites, representing far-ranging biomes including tundra, desert, and tall-grass prairies, as well as boreal, temperate, and tropical rainforests. They aim to identify what factors affect the coupled breakdown and use of carbon and nitrogen in streams. While carbon and nitrogen are inextricably linked, scientists remain stymied by the considerable spatial and temporal variation in the relationships between the two. The unprecedented global database being assembled by the project will allow the team to examine energy and nutrient cycling across seasons and environmental and management gradients.
Principal Investigator: Kimberly J. La Pierre, Meghan L. Avolio, Kevin R. Wilcox
Award Date: May 23, 2016
Description: Many global change drivers (GCDs) lead to chronic alterations in resource availability, and scientists anticipate that the magnitude and direction of ecosystem responses to these changes will be non-linear. To predict responses to GCDs across a wide variety of ecosystems, the working group will take advantage of 101 similar experiments done across 17 LTER sites, all of which have examined plant community responses to changes in resource availability. The group aims to discover whether changes in plant community structure, productivity, and carbon storage are predictive of shifts in ecosystem function.
Principal Investigator: Forest Isbell, Jane M. Cowles, Laura Dee
Award Date: April 1, 2017
Description: It seems like a simple question. Does biodiversity loss cause productivity loss? Most experiments to test the question are done on small plots. Scaling up to natural ecosystems introduces complications that could tip the balance toward a stronger—or a weaker—relationship. Drawing on data from biodiversity experiments at multiple LTERs and global observational and experimental networks, the Biodiversity and Productivity working group asks what role time scales, spatial scales, type of experiment, and ecosystem type have on the strength of this key relationship.
Principal Investigator: Lauren Hallett, Daniel Reuman, Katharine Suding
Award Date: March 1, 2017
Description: Populations of plants, animals, and microbes fluctuate all the time. Whether populations rise and fall in tandem, independently or alternately can affect ecological stability. Offset fluctuations between species can enhance ecosystem stability. Or alternate fluctuations of the same species in different regions can support species stability. Building on many sources of long-term data, the LTER Synchrony working group aims to understand the drivers and timescales of synchrony and its effect on ecological stability.