'Dimensions of Biodiversity'
Assistant professor Michael Madritch from Appalachian State
University’s Department of Biology is part of the National Science Foundation’s “Dimensions of
The goal of the decade-long NSF program is to transform how Earth’s biological diversity is described and understood by the year 2020.
Madritch is co-principal investigator on a $2 million collaborative project that was one of 13 selected for funding in 2013. He was awarded $120,000 to conduct his portion of the research at Appalachian, while the bulk of the work will be conducted at the Cedar Creek Long Term Ecological Research station in Minnesota.
Madritch is working with researchers from the University of Minnesota, University of Wisconsin at Madison and the University of Nebraska at Lincoln to apply novel remote sensing techniques to monitor biodiversity in experimental manipulations of plant diversity — allowing scientists to examine links between plant biodiversity, soil microbe diversity, and ecosystem function.
The work is important, he said, because of the rapid rate at which the earth is losing plant species to climate and land-use change.
“We are in the middle of a sixth mass extinction period,” Madritch said.
Unlike previous extinctions caused by rapid glaciation, volcanic activity and asteroid impacts, this one is caused by humans.
“We are losing diversity now much faster than we have in the past — anywhere from 1,000 to 10,000 times above background extinction rates,” he said. “That’s why there is a large push in ecological research in general to understand the consequences of biodiversity loss.”
Madritch is an ecosystem ecologist. His data and that collected by his co-researchers who are plant specialists will be correlated with information collected via aerial imaging spectroscopy data and other ground-based technologies to develop a new method to track changes in ecosystems.
“The remotely sensed data can be used as a proxy for other biologically important data, such as plant diversity and below-ground processes — soil, carbon and nutrient processes — and microbial community analyses,” he said. “Remote sensing of the plant canopy can give us an idea of what is going on belowground because the aboveground plant chemistry is tightly linked to belowground soil chemistry.”
Past NASA funding allowed Madritch to demonstrate the viability of using remotely sensed imaging as a surrogate for biological data for both canopy diversity and below-ground processes. The results of that work were recently published in the international journal, Philosophical Transactions of the Royal Society.
Working at an ecological research station in Minnesota that contains a diversity of well-established plants and trees, the researchers will collect and examine data from the peak growing season to see variations in field and forest canopies and then use that information to predict diversity in the plant community, the amount of biomass in the study area, if the soil is experiencing fast or slow nitrogen and carbon cycling, and if the soil communities differ between areas with different imaging spectroscopies.
“This is a small part of the larger effort by ecologists to determine how to best measure biodiversity, how ecosystems function, how they process nutrients and energy and their role in key ecosystem services such as carbon storage, nitrogen cycling, flood mitigation and water purification,” Madritch said. “All these ecosystem processes that we depend on are dependent on biodiversity.”
Developing a method to extrapolate remote sensing data related to plant and forest diversity will allow scientists to study larger areas and collect data more quickly.
“Part of the argument for using remote sensing is that in many cases we are losing diversity faster than we can measure it, especially in the tropics,” Madritch said. “One of the arguments for remote sensing is that it is a tool that can be used to measure change that’s happening too fast and on a scale that is too large for us to measure any other way.”
The scientists hope to expand the remote sensing method developed in Minnesota to tracking changes in biodiversity in other ecosystems, Madritch said.
“We have a good range of diversity that we can apply our remote sensing techniques to,” he said. “A lot of this is exploratory in the sense that it hasn’t been done before. Once we figure it out in a test system, we can apply it elsewhere.”