The Terrestrial Biogeochemistry Laboratory in the Department of Earth and Environmental Science of the University of Pennsylvania invites applicants for competitive Ph.D. fellowships in one of two research areas: Soil carbon biogeochemistry: Projects seek to quantify and characterize the recalcitrant pools of pyrogenic and geogenic carbon in soils. We’ll examine chemical transformations and dissolution as mechanisms controlling their fate in the critical zone. Urban biogeochemistry: New and evolving research projects to study the biogeochemical functioning of urban ecosystems with emphasis on cycling and storage of carbon and nutrients. Positions are ideal for candidates who have completed an MSc in soil science, geosciences, environmental chemistry, ecosystem science or related fields, but outstanding BSc graduates in such programs will be considered. For further information, please contact Dr. Alain Plante by email (email@example.com) or consult the department website (www.sas.upenn.edu/earth). Applications can be submitted directly online (https://www.applyweb.com/upenng/) before December 15.
In our our ongoing video series, “What are you doing today?“, undergraduate research assistant Madison Bell-Rosof explains why measure the specific surface area of soil samples.
In our our ongoing video series, “What are you doing today?“, undergraduate research assistant Hannah Sanders explains why she’s using dental tools to pick biochar chunks clean of soil.
I am extremely excited to be the latest addition to Prof. Plante’s lab (and thrilled about the new Netzsch autosampler); we have been planning this collaboration since first meeting at AGU (American Geophysical Union Fall Meeting) in 2013. At that time, I was a Ph.D. candidate Tulane University with Prof. Brad Rosenheim. My research focused on using thermal analyses and coupled radiocarbon and isotopic analyses to characterize organic matter stability in coastal soils and sedimentary deposits. After completing my Ph.D. the following year, I began a postdoctoral research position at the University of California – Merced with Prof. Marilyn Fogel. My research grew to focus on using hydrogen and carbon isotopes to trace inputs and subsequent storage of organic matter in forest soils, characterize dynamics of physical and chemical stabilization, as well as address the potential of soil organic matter in recording climate (precipitation) signals. Now, finally, as a postdoc at the University of Pennsylvania through a fellowship from the Office of the Vice Provost for Research, I am excited to continue researching mechanisms controlling organic matter stability and storage in soils, specifically, mineral interactions, effects of biochar/black carbon addition, and microbial impacts as well as improving our understanding of thermal analyses as they relate to particulate organic matter cycling.
A new grant (#1541588) from the Instrumentation and Facilities program in the NSF Division of Earth Sciences (NSF-EAR/IF) has allowed us to acquire new thermal analysis instrumentation for increased capacity of characterization of organic matter in soils and sediments. In addition to our existing Netzsch STA409 instrument coupled to an LI-840A CO2 and H2O infrared gas analyzer, we now have a Netzsch STA499 F3 Jupiter with a robotic automatic sample changer. The new instrument is also coupled to its own LI-840A for CO2 and H2O evolved gas analysis.
Thermal analysis techniques are increasingly used as part of a suite of methods to characterize organic matter stability and quality in soils, sediments, composts, biochars, and other environmental samples. Our previous equipment was a single-sample, manual-loading operation that could handle 3-4 samples per working day. That kind of sample throughput was unable to meet the geoscience research community’s demand for rapid and data-rich characterization of organic matter in soils and sediments. The new autosampler-equipped thermal analyzer will allow samples to be analyzed unsupervised around the clock, thus allowing its application in large, multidisciplinary projects such the cross-CZO characterization of controls on soil organic matter dynamics. Other research projects that will greatly benefit from the new instrumentation include correlation of thermal analysis results with conventional, analytical methods of characterizing SOM composition, simultaneous quantification of organic, inorganic and pyrogenic C in soils and sediments, and thermal fractionation as a preparatory step for radiocarbon analysis. At present, the feasibility of these large-scale, “big-data” styled research projects is severely limited by low sample throughput. The new instrument is part of an open multi-user facility that will be available for collaborators locally and worldwide. The relative ease and speed of analysis enables its use by undergraduate students, directly supporting undergraduate research and teaching tool in the Earth, environmental, and materials sciences. We are currently working on updating our data processing pipeline to allow users and collaborators to access raw data and process them using open and reproducible methods that can be accessed online.
In our our ongoing video series, “What are you doing today?“, undergraduate research assistant and Velay Fellow Maddie Tilyou explains how she’s weighing soil samples for carbon analysis.