About the Trace Gas Biogeochemistry Group

A young man and woman draw water from a bog while squatting on a boardwalk.

About Us

We study the response of carbon, nitrogen and other element cycles to climate and land use change. Our research is located in subarctic, temperate, and tropical biomes that include tundra, forested, urban, and agricultural areas. We focus on trace gas biogeochemistry within these ecosystems, developing and utilizing a variety of techniques such as in-situ sensors, remote sensing, and process-based modeling from local to global scales. We work at the intersection between science and society, collaborating with students, educators, stakeholders, and citizens.

We seek to advance scientific discovery through collaboration, mentorship and outreach by building a strong, diverse and inclusive research community. We pursue questions of both fundamental scientific interest and broad societal relevance, while at the same time encouraging our group members’ unique motivations and interests and the benefits they bring. We communicate research in creative ways to increase the broader impact of our work by engaging stakeholders, the public and k-12 teachers and students.

Principal Investigators:
Ruth Varner
Alexandra Contosta
Claire Treat

Research Staff:
Nell Campbell
Apryl Perry

Graduate Students:
Sophia Burke: CH4 flux dynamics in subarctic peatland thaw ponds using field and remote sensing techniques
Paige Clarizia: Greenhouse gas emissions from terrestrial and aqueous ecosystems using automated sampling techniques
M. Florencia Fahnestock: Mercury cycling in wetland and sub-Arctic mire ecosystems as they respond to climate change
Christopher Horruitiner: Vegetation effects on CH4 dynamics in discontinuous permafrost peatland lakes
Tamara Marcus: Microbial controls on methane emissions in sub-arctic lakes
Kellen McArthur: Paleoenvironmental change using proxy records from lake sediment and peat cores
Apryl Perry: Drivers of CH4 ebullition in a temperate fen
Clarice Perryman: Geochemical controls of methanotrophy in arctic and temperate peatlands

  • From Archaea to the Atmosphere (NASA IDS: R. Varner PI) This project aims to scale emissions of methane across the arctic using a combination of microbial and isotopic measurements, UAS surveys to map vegetations, biogeochemical modeling and remote sensing. This project is part of NASA's Arctic Boreal Vulnerability Experiment (ABoVE).
  • Exploring the interactions between carbon cycling, land use and climate change (NASA CCS; J. Xiao is PI). This project examines land use-climate interactions in the human-dominated region of southern New Hampshire that includes urban, suburban, agricultural, and forested land uses. 
  • Soil carbon storage and greenhouse gas losses in intensively grazed pastures (USDA ORG; PI A. Contosta). This study explores linkages among grazing management, soil carbon storage, and greenhouse gas losses through a combination of field measurements, lab analyses, and process-based modeling. We are translating our research into a decision support system that will enable organic dairy farmers to make science-based pasture management decisions that promote soil C sequestration and reduce soil greenhouse gas emissions.
  • Promoting ecosystem services during the conversion of forests to fields in New England (USDA AFRI, R Smith PI). This project seeks to determine how forest-to-agriculture conversions, particularly pasture and silvopasture, affect ecosystem services such as nutrient retention, water availability, climate regulation, and forage supply.
  • Winter Climate Change in the Northern Forest (NSRC; A. Contosta). The goal of this work is to determine how climate change impacts winter ecological and biogeochemical processes, and how this changing winter landscape affects Northern Forest communities.
  • Winter Weather Whiplash (SESYNC; A. Contosta). This project is developing a suite of winter weather whiplash indices and associated physical, ecological, biogeochemical, and socioeconomic response metrics to determine the extent to which winter weather whiplash events have cascading impacts on ecosystems and their services.
  • DOE funded Isogenie project (R. Varner).
  • Global Sustainable Bioenergy Initiative (Nell Campbell).
  • Bringing DNDC into the Predictive Ecosystem Analyzer (PEcAn) project (ESRC)(Varner, Contosta, Campbell). This project is expanding our capacity for ecosystem model analyses at scales relevant for policy and land management by integrating the ecosystem model DeNitrification-DeComposition (DNDC) into the PEcAn system.

Trace gas analysis using for CH4 using a gas chromatograph equipped with a flame ionization detector (GC-FID; Shimadzu 8A); N2O also using a gas chromatograph (GC-ECD; Shimadzu 8A); and CO2 using an infrared gas analyzer (IRGA; Li-Cor Li 6262). We also have a laser to measure del13-CH4 (Aerodyne, Inc.).

  • Clarice Perryman, along with two other graduates students from UNH, was awarded an Outstanding Student Presentation Award at the Fall Meeting of the American Geophysical Union.
  • Contosta was featured in a short film highlighting open source and transparent data collection, modeling, and decision support tools for sustainable agriculture.
  • Contosta and colleagues publish a paper examining changes in the timing and duration of the vernal window in Global Change Biology (doi: 10.1111/gcb.13517).

Selected media featuring the story:

March 9, 2017: Is Spring Getting Longer? UNH Research Points to a Lengthening “Vernal Window”
March 23, 2017: How climate change is altering spring
March 31, 2017:  Wildlife may suffer from longer transition into spring