This article has been adapted from its original publication at the University of Arizona website. It was authored by Daniel Stolte.
Researchers from EESA and California Lutheran University will join UArizona in establishing a complete ecosystem – with plants, artificial rain and sophisticated monitoring technology – on the large artificial hillslopes at the Landscape Evolution Observatory, or LEO, located inside UArizona’s Biosphere 2. The experiment will offer scientists a detailed look at how emergent plant life interacts with soil, water and carbon dioxide from the atmosphere to create more complex ecosystems.
“In a nutshell, we’re getting ready to put life on LEO in the form of plants,” said Scott Saleska, a professor in the Department of Ecology and Evolutionary Biology at UArizona who took over as LEO’s director of science earlier this year. “This grant will allow us to answer a question central to ecology: Can we predict what is going to happen when we build up an ecosystem from scratch? LEO allows us to literally watch life’s complexity build up from ground zero.”
LEO is the world’s largest laboratory experiment in the interdisciplinary earth sciences. The experiment consists of three artificial landscapes that mimic watersheds in the natural world, each contained within elaborate steel structures housed in three adjacent bays under the glass-and-steel domes of Biosphere 2. Each hillslope is 100 feet long and 35 feet wide and blanketed with 1 million pounds of crushed basalt rock, layered 3 feet deep. Each of LEO’s hillslopes is studded with 1,900 sensors that allow scientists to observe each step in the landscapes’ evolution – from lifeless soil to living, breathing landscapes that will ultimately support complex microbial and vascular plant communities.
“An important component of the project will be developing mechanistic models of the biotic and abiotic interactions that affect how life develops on nascent soils,” said EESA Senior Scientist William Riley. “We’ll be applying models that we are using in several large DOE projects, including NGEE-Arctic, the Watershed Function Scientific Focus Area (SFA), and the Belowground Biogeochemistry SFA. This project is an exciting opportunity to improve mechanistic understanding of processes and analyze interconnections that affect emergent ecosystem dynamics.”
Over the past five years, researchers have used LEO to gain in-depth knowledge of how landscapes evolve in the absence of plant life other than microbes and mosses. Those studies focused on the interactions between soil and water, with the water being provided through a sophisticated irrigation system that simulates various kinds of rain. The new NSF grant kicks off a new phase of the project, allowing researchers to study more complex interactions between the physical and biological components of LEO’s ecosystem, particularly between tiny microbial communities and higher plants.
The team will use LEO’s hillslopes as models for watershed environments in the natural world. Experiments will test how water flows through landscapes, how that affects the weathering of rock to soil, and the effects of those processes on landscapes and their biological habitability.
The project, titled “Growing a new science of landscape terraformation: The convergence of rock, fluids, and life to form complex ecosystems across scales,” was selected by NSF under its Growing Convergence Research program, which aims to solve complex research problems with a focus on societal needs. In addition to experts in hydrology, geochemistry, evolutionary genomics and ecology, the LEO team will include anthropologists who study cultures of science, with the goal of breaking new ground in how researchers from historically separate disciplines can better share and integrate their ideas and insights for the benefit of the world.
“These are extremely competitive grants, specifically created to address some of the world’s greatest challenges, and to even be considered requires a portfolio of interdisciplinary scholarship and technological capability that the university excels at bringing together,” said University of Arizona President Robert C. Robbins. “The fact that our researchers continue to attract these types of grants speaks to the unique ecosystem of talent, technology and perseverance that our faculty bring to the table.”
Other members of the LEO project steering committee include Jon Chorover, head of the Department of Environmental Science; Jennifer Croissant, associate professor in the Department of Gender and Women’s Studies; and Elizabeth “Betsy” Arnold, a professor in the School of Plant Sciences and the Department of Ecology and Evolutionary Biology.