Welcome to Nevada, known worldwide for over-the-top casino resorts, hard-to-beat ski retreats, and state-of-the art global change research. That's right, research. And if you don't believe us, ask the new executive director of DRI's Biological Sciences Center, Dr. James Coleman. Coleman arrived at DRI in July, sporting an impressive résumé that includes a Yale Ph.D. in ecology, postdoctoral work at Harvard and Stanford, a prestigious "Young Investigator Award" from the National Science Foundation (NSF), and recognition from the respected British journal The Scientist for contributing one of the ten most significant papers on global climate change since 1993.

Dr. Jim Coleman in the Frits Went Laboratory of GBERL between EcoCELLs and Ecopods (the smaller versions of the EcoCELLs).

It's Ivy League meets the wild West, and Coleman thinks that's just great. "Nevada is an incredible place to do science. For one thing, scientists in this state seem to be viewed as a significant resource. We have access to the important people, and they are genuinely interested in what we're trying to do. And the campuses (DRI, the University of Nevada, Reno and the University of Nevada, Las Vegas) work well together."

Coleman says that Nevada is especially friendly to ecological studies, since its borders contain a variety of distinct ecosystems--southern Nevada's deserts, the Truckee's riparian banks, the ponderosa pine forests of the Sierra, and the brush lands of the Great Basin. "It's like a scale model of the world--a perfect place to compare change across ecosystems."

But, beyond Nevada's friendly atmosphere and serendipitous environment, there is the research. "Nevada, as a whole, has an incredibly strong global change research program," says Coleman. Supported by the NSF and the Department of Energy under a program called EPSCoR (Experimental Program to Stimulate Competitive Research), 20 to 30 researchers from DRI, the University of Nevada, Las Vegas (UNLV), and the University of Nevada, Reno (UNR) form what they call the global change biology group--studying the mechanisms of global change from the reaction of the tiniest molecule to the responses of whole ecosystems and landscapes. Coleman heads the EPSCoR projects at DRI, while Dr. Jeff Seemann leads the UNR researchers and Dr. Stan Smith pilots the UNLV team. Interestingly, both Seemann and Smith originally came to Nevada to work for DRI.

Recently reviewed by the American Association for the Advancement of Science, Nevada's global change EPSCOR program received a glowing report. "Nevada's program is very close to being competitive with programs at the likes of Stanford and Duke," says Coleman, "and, in this area at least, there is almost seamless collaboration among the campuses." Exceptional researchers are the biggest reasons behind this success story, and they're being helped out by a unique facility: the Great Basin Environmental Research Laboratory, known more succinctly by its acronym of GBERL (pronounced gerbil). Looking like a very sophisticated greenhouse, GBERL houses research tools that are giving scientists the ability to understand the environment better than ever before. These tools have their own catchy acronym, EcoCELLs, for Ecologically Controlled Enclosed Lysimeter Laboratories. "These are unique facilities, even internationally, for examining ecosystem processes in a controlled environment," says Coleman. "EcoCELLs are big enough that a lot of "normal" ecological actions can happen but small enough that we can control and measure everything about the environment."

Coleman standing in an unplanted EcoCELL

In the past, explains Coleman, measurement of gas and nutrient exchange in plants was more often done one leaf at a time. "A small but sophisticated chamber called a mass-balance cuvette was slapped onto a leaf to measure the water and gases moving through the leaf. You had to have controlled temperature and humidity since all these things would affect the flux readings." Two enterprising DRI researchers, Peter Ross and Dr. J. Timothy Ball, thought it would be useful to have a mass-balance cuvette that would work for an entire ecosystem. With this modest idea in mind, they created the EcoCELL.

From the outside, an EcoCELL may strike you as little more than a tall terrarium. In fact, it is an incredibly sophisticated chamber where scientists can carefully measure and control everything--water, gases, nutrients--that goes into a plant community. And scientists can also collect and measure everything that comes out. An EcoCELL can be equipped for various readings and monitored 24 hours a day to provide continuous measurements of how nutrients, gases, and water flow through the system. Roots can be explored up to eight feet deep for a virtually natural soil profile, and they can be sampled and studied without being displaced. In short, explains Coleman, "You have the artificial control of a traditional greenhouse with a very good simulation--the best anyone has been able to achieve--of what actually goes on in the field."

In the field, whole-ecosystem processes like carbon and water flux are difficult, if not impossible, to continuously measure. "Instead," says Coleman, "we often have to measure processes that occur, for example, on individual leaves or in a subsample of soil, and then scale up." In other words, scientists take what they know happens on the small scale and make what amounts to very well educated guesses about what they believe happens on a large scale. "In the EcoCELLs," Coleman continues, Agiven that we have continuous and accurate measures of whole-system processes, we can take a series of measurements of soil and leaves and determine just how each of these scale up to define the larger processes, the ones we really want to know about. We want to make the jump from what happens in an individual plant to what happens in the plant community in the EcoCELL and ultimately to what actually happens on earth. There is probably no other facility in the world, other than maybe the Biosphere II, that is capable of that degree of scaling."

Coleman, along with DRI's Dr. Dale Johnson and Dr. Weixin Cheng, will be taking advantage of these capabilities for a project recently funded by the Andrew W. Mellon Foundation. A grant of approximately $400,000 will be split evenly between DRI and the University of Arkansas, where Dr. R. Dave Evans leads the project. DRI has also received State of Nevada matching funds for the project which will be looking at the issues of scaling measurements up to ecosystem levels. A particularly perplexing question in ecosystem research will be addressed: the mystery of the missing carbon and nitrogen.

DRI Biological Sciences Center faculty Dr. Dale Johnson (right) and Dr. Weixin Cheng in an EcoCELL harvesting experimental plans for lab analysis. Each EcoCELL is a separate mesocosm designed as an open-flow mass-balance system for the measurement of materials. Air temperature and humidity, trace gas concentrations, and air flow rates are strictly controlled and precisely measured. Temperature control is achieved without condensation; humidity is controlled by regulating the dew point and flow rate of incoming air; and wind speed and flow patterns are adjustable.

Carbon is taken up by plants from the air as carbon dioxide. Nitrogen is also an important nutrient taken up by roots from the soil. Presumably, careful measurement of a plant's emissions and tissues would account for all the carbon a plant takes in and for all the nitrogen added to a system--whatever goes in must stay in or come out, a balanced budget. But in nature, this equation doesn't always balance. And while some may be willing to turn a blind eye to that scenario, scientists want answers. "No one has ever been able to account for all the carbon in an ecosystem that appears to get taken up by plants," explains Coleman, "and we still don't know what happens to all the nitrogen we put into a system. The EcoCELLs are a perfect place to solve this mystery."

Finally, the project will attempt to identify the different reactions of an ecosystem to gradual, as opposed to sudden, changes in environmental factors, in this case nitrogen. "It's intuitive that ecosystems might respond in very different ways to a sudden change--say adding 100 kilograms of nitrogen in one day--versus a gradual change--adding one kilogram of nitrogen a year for 100 years. Yet most of what we know of ecosystem responses to things like rising carbon dioxide is based on studies using sudden drastic changes," says Coleman.

GBERL and its EcoCELLs are proving to be powerful tools as Nevada researchers strive to understand the complicated processes involved with global change. Coleman also sees them as having potential for aiding with the somewhat more tangible problems of environmental pollution. Of particular interest to Nevada would be a careful study of mercury contamination in soils, a remnant of mining practices used during the Comstock Era. "We know plants can take up mercury from the soil, but when we measure the mercury they've taken in and how much remains in their tissue, it doesn't add up. It's likely that they are emitting gaseous mercury, which is potentially hazardous, but how much is emitted from a plant community is not known." Coleman hopes to find funding to equip the EcoCELLs to measure gaseous mercury emissions in plants and to understand the processes and factors that might affect those emissions. The same types of studies could be done with pesticides for the first real look at how pesticide use might affect the environment.

Biological Technician Valerie Yturiaga tends to planted Ecopods. Thirty of the naturally lit growth chambers are available in the Frits Went Laboratory for controlled environmental studies.

Moving into the next century, Coleman has his sites set on attracting five or six new scientists to round out his group's research expertise and to take full advantage of GBERL's instrumentation.

"This planned growth would give us the full breadth of scaling capabilities and methods, from the molecular level on up. And there are some world-class people interested in joining us."

Welcome to Nevada--distinguished scientists, unique research facilities, acclaimed environmental programs. You may have hit the jackpot and found the key to understanding global change.
Jackie Allen