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On Tuesday June 24, 2014, Congressman McNerney (D-CA) gave a floor speech on the research conducted in the Berhe Biogeochemistry lab at UC Merced.

The speech that the congressman gave included: “In the midst of California’s worst drought on record, researchers at UC Merced are studying the effects that drought, fire and global climate change are having on soil and water resources. One such researcher, Dr. Berhe is supported by the National Science Foundation to investigate the implications of fire, erosion, and climate change on soil processes. Catastrophic events, such as California’s Rim Fire which burned over 250,000 acres in the Sierra Nevada last year, can alter the soil carbon storage potential and water holding capacity. Additionally, changes in climate and drought also lower the water holding capacity of meadow soils and lead to high rates of surface runoff. These changes affect the ability of the soil to help regulate the climate and store water in the Sierra Nevada, California’s largest source of water storage. Research like Dr. Berhe’s is critical for addressing challenges to the soil’s ability to sequester atmospheric carbon dioxide, water security and the health of the ecosystem.”

Previously, Asmeret also met and discussed research in our lab with Congressman Costa (D-CA); Congressman McNearney (D-CA); congressional staff from the offices of Congressmen Garamendi, McClintock, Denham, and Valadao; and staffers from Senator Feinstein and Senator Boxer’s offices in Washington DC, on May 7, 2014.

Asmeret receives NSF’s most prestigious award for early career scientists for work dealing with “CAREER:Persistence of soil organic matter in dynamic landscapes: interactive effects of fire and erosion”

Fire, erosion, and soil carbon (C) storage and persistence overlap in space and time. However, we currently lack complete understanding on how and why the interaction of fire and erosional distribution of soil materials control persistence of bulk soil organic matter (SOM) and pyrogenic C (PyC, also referred to as black carbon) in dynamic landscapes. This work will use molecular- and nano-scale techniques to determine how SOM persistence varies along multiple spatial (plot, hillslope, and watersheds) and temporal scales (seasonal, annual, and decadal). The outcome of this project will be better integration of biogeochemical and geomorphological approaches to derive improved representation of mechanisms that regulate SOM persistence in dynamic landscapes that routinely experience more than one perturbation.

This CAREER project will develop improved understanding on the dynamics of bulk SOM and PyC in fire-adapted upland ecosystems and enable teaching of graduate and undergraduate students, and K-12 teachers. The findings from this project will transform the way we (a) account for changes in C storage in fire-prone systems, and (b) model response of fire-prone upland ecosystems to changes in climate and/or management practices. Moreover, in this project, I will: (1) teach undergraduate students and high school teachers about the critical zone, and develop and publish lesson plans for high-school level earth system science; (2) provide scientific training for a graduate student and a postdoc; and (3) learn advanced techniques that I will apply in my research and teaching.

UC Merced article: NSF Early Career Award Honors Professor’s Research and Potential

Two Research Experience for Undergraduates positions are available for work that focuses on water resources and soil nutrients in the Southern Sierra Critical Zone observatory. Please visit http://criticalzone.org/sierra/news/story/reu-2014/ for more information, and don’t hesitate to contact Asmeret if you have any questions.
The deadline for submission is 11:59 pm PDT, May 13, 2014.

Chelsea Arnold successfully defended her dissertation on friday May 2, 2014. The title of Chelsea’s dissertation is ” Coupled hydrological and biogeochemical dynamics in high elevation meadows: thresholds, resiliency and change.”

Abstract: High elevation meadow ecosystems play a fundamental role in the storage and movement of water from the snowpack to the streams. Due to the coupled nature of the hydrological and biogeochemical cycles in the meadows, it is expected that a change in hydrology will impact biogeochemistry and vice versa. My dissertation research investigated the gaps in our knowledge of the coupled hydrology and carbon cycling of meadow soils, and forges new territory in our understanding of the impacts of lowered water tables and desiccation on the hydrologic resiliency of those soils. This knowledge is critical in snowmelt-dominated watersheds, where meadows (both high elevation and montane) serve as natural storage reservoirs that feed both streams and groundwater. Using the last three extreme precipitation years in the Sierra Nevada Mountains, I specifically focused on three main themes of resiliency, thresholds and change in high elevation meadow ecosystems, I found that a) nonlinear responses in ecosystem processes can cause ecosystems to shift from a sink to a source of carbon contributing to local (degradation of ecosystem), regional (loss of ecosystem services) and global effects (feedback to atmosphere), b) winter drought and spring frost events can significantly damage vegetation, reducing the productivity of vegetation, which leads to a decrease in carbon sequestration, c) thresholds in moisture availability can influence the magnitude of carbon loss via soil respiration, d) Longer growing season with little summer precipitation contributed to severe desiccation of meadow soils which caused an irreversible change in the structure of the soil and subsequent loss of porosity and permeability.

Congratulation to the super-mom/teacher/scientist and pastry chef extraordinaire!

Ph.D. candidate Chelsea Arnold travelled to the State of California Capitol in Sacramento during Graduate Research Advocacy Day on March 12, 2014

Chelsea was one of the two University of California graduate students that were chosen to accompany University of California President Janet Napolitano and Nobel Prize winner Prof. Randy Schekman to meet with California governor Jerry Brown  in his office.

This is a great honor and recognition for Chelsea and UC Merced. Congratulations Chelsea and great job being an ambassador for graduate education in the UC system.

Chelsea’s dissertation research was also highlighted as one of the important topics of discussion with lawmakers in the state capitol.

Asmeret appointed as a new Associate Editor for two academic journals:

• Biogeochemistry and
• SOIL (A new Journal from the European Geosciences Union, starting May 2014) 

This year, we have Ph.D. student positions available in UC Merced for work in:
(a) a project investigating the effect of fire on soil structure and organic matter dynamics (for more information see UCM student position – fire and agg ), and
b) four Ph.D. student positions in the Southern Sierra Critical Zone observatory project in projects spanning hydrology, microbiology, biogeochemistry and geochemistry (for more information see SSCZO student positions ad 2013a_AAB_SCH).

Students with a MSc in Soil Science, Hydrology, Geology, or related fields, or candidates with research experience in these areas are strongly encouraged to apply. The application deadline for graduate studies at UC Merced is January 15, 2014. After the deadline potential students should directly contact Prof. Berhe or other members of the Environmental Systems graduate group over email.

Announcements

• Applications for  graduate study at UC Merced are due mid January every year. Please contact Asmeret before submitting an application to join our group.

• Applications for a UC President’s Postdoctoral Fellowship are due typically in November of each year. Please contact Asmeret as soon as possible if you are interested in submitting an application to join our group.

• We occasionally have openings for postdoctoral scholar, research associate, technician or undergraduate student positions. To inquire about possibility for joining our group please send an e-mail with your CV and brief description of your research interests to Prof. Asmeret Asefaw Berhe at aaberhe(at)ucmerced(dot)edu.