IML-CZO Investigator Profiles: Aaron Packman (Northwestern University)


Dr. Aaron Packman is a professor of civil and environmental engineering at Northwestern University. (Northwestern University
Dr. Aaron Packman is a professor of civil and environmental engineering at Northwestern University. (Northwestern University)
Nick Fetty | April 8, 2016

This is part of a series of articles featuring investigators and researchers with the IML-CZO project which “works to understand how land-use changes affect the long-term resilience of the critical zone.”

Journalist Michael Pollan once said: “In one handful of soil there are more organisms than there are humans on earth and we are only beginning to understand the vast network of beings right beneath our feet.” The quest to understanding this vast network is part of the research focus of IML-CZO investigator Dr. Aaron Packman.

Dr. Packman – a professor of civil and environmental engineering at Northwestern University – is studying microbial dynamics of the Critical Zone.

“The metacommunity gene sequencing we’re doing is based on extracting all DNA from an environmental sample, like a soil or water sample, and then amplifying a portion that is characteristic for bacteria and archaea,” said Dr. Packman. “The sequencing we are using is intended to identify the presence and diversity of different organisms in the community.

Dr. Packman added that this research was not originally part of the IML-CZO project but he and his research team were able to initiate it with the support of IML directors Praveen Kumar and Thanos Papanicolau as well as the Earth Microbiome Project, an “multidisciplinary effort to analyze microbial communities across the globe.”

Similar to the Earth Microbiome Project, the IML has an interdisciplinary focus which combines researchers and students from fields within engineering and science to those outside of it such as education and journalism.

“Interdisciplinary research is essential to understanding and managing the complexity of the Critical Zone.  Most historical work was pursued from a disciplinary perspective, so our available information on the Critical Zone is fragmentary — a lot of different types of data, but collected at different places and different times,” Dr. Packman said. “The main challenge now is to integrate this information into a holistic understanding of overall Critical Zone functioning, and to use that information to manage land, water, and ecosystems in a sustainable way.  That requires an interdisciplinary approach.”

The emphasis on interdisciplinary research is also part of the mission of the Northwestern Center for Water Research which was founded in 2015. Dr. Packman is the center’s director and he said that not only does the center aim to bring together different disciplines but it also aims to bridge Northwestern University – a private college – and businesses with governmental agencies and other public entities.

“The Current public-private partnership will make Northwestern’s Water Center even stronger,” Dr. Packman said in a 2016 press release. “Working with strong industrial, governmental and community partners will help us achieve our goal of developing global solutions for regional problems.”

Dr. Packman holds degrees from Washington University (B.S. ’91) in St. Louis and the California Institute of Technology (M.S. ’92; PhD ‘97) in Pasadena. He has also studied in Chile, Italy, New Zealand, and Sweden.

“I have found that people are much the same everywhere I’ve been, but the landscapes vary tremendously.  Growing up in the Mississippi River Valley, I was used to really big rivers but a really flat landscape.  I really like working on different rivers around the world, and I also like working in diverse landscapes,” he said.

Part of the goal of the IML-CZO is to not only inform other scientists and researchers about various aspects of the Critical Zone but also to educate the public. Dr. Packman said that his research is of particular interest to Midwesterners because of the impact that current agriculture practices have on the landscape and the associated public health issues.

“We need to be able to sustainably manage water, soil, and microbial landscapes. In the Midwest, we’ve designed the entire landscape to produce food, but we don’t yet understand how this has changed the water and soil microbial ecosystems. It is important to know this so we can maintain agricultural productivity while avoiding potential problems like waterborne disease.”

IML-CZO Investigator Profiles: Neal Blair (Northwestern University)


Dr. Neal Blair has joint appointments in Civil & Environmental Engineering and Earth & Planetary Sciences at Northwestern University (Northwestern University)
Nick Fetty | March 11, 2016

This is part of a series of articles featuring investigators and researchers with the IML-CZO project which “works to understand how land-use changes affect the long-term resilience of the critical zone.”

While urban and rural areas are seemingly polar opposites the two different areas depend greatly on one another, according to IML-CZO investigator and Northwestern University professor Dr. Neal Blair.

“Rural agricultural landscapes are responsible for much of the food that makes it to urban areas. The bioethanol that we used for transportation is also produced from the same land,” said Dr. Blair. “If we don’t manage the agricultural landscapes in a sustainable fashion, and especially in the face of increasing demand and climate change, the high population areas will be significantly stressed. Research in the IML-CZO should better inform our management.”

Northwestern University is located in Evanston, Illinois – a northern suburb of Chicago – in a state where agriculture is a major industry in the rural areas. Illinois led the nation in soybean production (by bushel) in 2014 and was second behind Iowa in corn production (by bushel) that same year.

Dr. Blair – who has joint appointments in Civil & Environmental Engineering and Earth & Planetary Sciences at Northwestern – focuses on the role of the carbon cycle on agricultural land specifically and the Critical Zone – where terrestrial life meets its requirements – air, water and soil.

“When we speak of the C-cycle, we are typically referring to the conversion of atmospheric carbon dioxide – or CO2 – to organic matter in plants and soils and then back to CO2. The C-cycle is an essential component of the Critical Zone. For instance, soil organic matter acts as a glue between soil particles causing them to aggregate. This makes erosion more difficult.”

Part of Dr. Blair’s research focus is to prevent agricultural land degradation such as what occurred on the American Great Plains during the first half of the twentieth century, an event that came to be known as The Dust Bowl.

“The Dust Bowl of the 1930’s was caused by a combination of extreme drought and the loss of soil organic matter via excessive tillage. We have consequently developed conservation methods to maintain the necessary C-storage in soils,” he said.

Dr. Blair studied chemistry as an undergraduate at the University of Maryland and then went to Stanford to earn a PhD in Organic Chemistry. Different parts of the country face different environmental challenges, particularly in regard to water management.

“One of the major differences between the Midwest and the West coast, and especially California, is water management. The low relief of the Midwest has forced us to build extra drainage into the landscape so that water does not pool. As a result water is rapidly exported along with a significant portion of applied fertilizers. Ultimately the nutrients are delivered to the Gulf of Mexico by the Mississippi River where they cause hypoxic (dead) zones.”

As of August 2015, the Gulf of Mexico “dead zone” was the size of Connecticut and Rhode Island combined, or more than 5,000 square miles. Excessive nutrient pollution in the water lowers oxygen levels which has devastated fish and marine wildlife and in turn affected the economy of the region. However, the West Coast faces a different set of challenges.

“An overabundance of water has not been a problem for much of California agriculture. The high relief in some areas, such as in the Eel River CZO, coupled with land use drives rapid soil and bedrock erosion rates. Land sliding can be a major problem in some areas.”

The effects of climate change only exacerbate the issues that Dr. Blair and his colleagues study. Part of his goal with the IML-CZO is to study these phenomena so he and can other researchers can better understand these issues and educate the public about them.

“Climate change in the form of increased temperatures, more frequent drought and/or more extreme precipitation events will likely impact the Critical Zone C-cycle in ways we do not fully understand. An important objective of the IML-CZO research is to better understand how the Midwestern agricultural ecosystems will respond to these future perturbations.”

Midwest researchers come together for research project


Doug Schnoebelen, left, explains early 20th century mussel production along the Mississippi River during the CZO-IML conference on July 29, 2015. (Photo by Nick Fetty)
Doug Schnoebelen explains early 20th century mussel production along the Mississippi River during the CZO-IML conference on July 29, 2015. From left, Schnoebelen, Praveen Kumar, Thanos Papanicolaou, and Chris Wilson. (Photo by Nick Fetty)

Nick Fetty | July 30, 2015

Roughly 30 students, professors, and researchers from six different institutions met in Muscatine this week to discuss a collaborative research effort to improve land, water, and air quality in the Midwest.

This Midwestern project is part of a nation-wide project known as the Critical Zone Observatory (CZO) an effort by the National Science Foundation to “[study] the zone where rock meets life.” The Midwestern project is called the CZO-IML (Intensely Managed Landscapes) and focuses on watersheds and lands in Illinois, Iowa, and Minnesota.

The Lucille A. Carver Mississippi Riverside Environmental Research Station (LACMRERS) in Muscatine hosted the IML-CZO conference which began Tuesday and ends today. This marked the second annual meeting for what will be a five year project.

“The first year was a lot of planning and field campaigns. The second year we’ve collected some data will be able to get that back to look at the results. We finally have some things to discuss, some real science,” said LACMRERS Director Doug Schnoebelen.

Schnoebelen, who also serves as a contributor for the IML-CZO project as well as a member of CGRER, said he hopes this research will be helpful not just for farmers and watershed managers but also for the general public.

“We’re hoping to look at an integrated approach and that’s what the Critical Zone is, being able to say something about water movement, soil conservation, transformation of carbon and energy in the environment. All of these things are really critical to the soil, the water, and the way we live.”

The conference brought together researchers from Indiana University, Northwestern University, Purdue University, University of Illinois, University of Iowa, and University of Tennessee. Schnoebelen said this emphasis on collaboration over competition has been key to the success of the project. He added that he is also grateful the CZO chose to support a Midwestern research project since much of the CZO’s other research takes place on the coasts.

“I think it was important when the national team came out and they realized how managed our landscape was and how important this research really was. It’s not just flyover country in the Midwest, it’s a critical part of our economy for food and energy.”