Introduction

Our research focuses on understanding how land management practices influence greenhouse gas and reactive trace gas emissions and how these practices can be adapted to minimize the negative impact of managed lands on climate, water, and air quality. Our research is conducted across diverse managed systems including restored peatlands, tidal wetlands, agroecosystems, and rangelands. We employ high-frequency in-situ field measurements and process-based biogeochemical modeling with an emphasis on greenhouse gas and reactive trace gas emissions. We also lead and collaborate on regional to national-scale monitoring and modeling projects and contribute to, advance, and evaluate carbon offset policies. 

Research in Coastal Wetlands

Tidal Wetlands
We are investigating carbon cycling in tidal wetlands, where both atmospheric and hydrologic carbon fluxes significantly influence net ecosystem carbon balance and soil carbon accumulation rates. In 2018, we established an eddy covariance tower in the Eden Landing Ecological Reserve (US-Edn), located in South San Francisco Bay, just 15min from Cal State East Bay's Hayward campus. Eden Landing is part of the South Bay Salt Pond Restoration Project, the largest wetland restoration project in the western U.S.

We also collaborate with a larger network of eddy covariance sites in tidal wetlands across North America. This network is called NATURA, short for Network of north American Tidal wetlands: Understanding through coordinated Research Activities funded by the Department of Energy.

We have developed a process-based biogeochemical model (PEPRMT) to predict daily to annual carbon dioxide and methane budgets in wetlands. This model has been approved for use in the voluntary carbon market, under the American Carbon Registry's offset methodology for wetland restoration.  Recent collaborative efforts led to the coupling of the PEPRMT model with another process-based model (CMEM; Cohort Marsh Equilibrium Model) which simulates dynamic soil accretion in tidal environments. The PEPRMT-Tidal-CMEM model predicts gross primary productivity, ecosystem respiration, and methane exchange as a function of the availability of multiple carbon pools, water table height, and redox chemistry.
Model development and network coordination is aimed at advancing our understanding of carbon cycling in tidal wetlands.



Wetlands in the Sacramento-San Joaquin Delta
We are investigating how land management and carbon credit protocols can be used to protect a critical water supply: the Sacramento-San Joaquin River Delta. Our work in the Delta is focused on studying the greenhouse gas effect of converting drained agricultural lands back to flooded conditions, thereby reversing soil subsidence, protecting an important water supply and providing wildlife habitat. This work is part of a long-term collaboration with the Berkeley Biometeorology Lab.

Research in Managed Lands:
​Rangelands and Agroecosystems

Compost Amendments to Rangelands
Compost amendments to rangelands have been shown to enhance soil carbon sequestration while simultaneously lowering greenhouse gas emissions from urban and agricultural waste streams. Amending soils with compost provides many co-benefits including reduced landfill and manure storage loads and emissions, increased agricultural production, enhanced drought resilience, and soil health.

We are investigating the carbon sequestration potential of compost-amended rangelands at CSU East Bay's Concord Campus Galindo Creek Field Station. Carbon and water cycling is being investigated through ecosystem-scale measurements of carbon dioxide exchange and evapotranspiration via the eddy covariance method. The eddy tower was established in June 2019 and will be maintained prior to and following a one-time application of compost in 2020.

This work was supported by the CA Strategic Growth Council as part of the Working Lands Innovation Center which aims to scale and sustain carbon dioxide capture and greenhouse gas emissions reductions by deploying a suite of cutting-edge soil amendment technologies (rock amendments, compost and biochar).
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Soil Carbon Accrual Project
This project is funded by the UC Office of the President designed to compare carbon cycling associated with conventional agriculture (full tillage; herbicide; fertilizers; pesticides and no cover) to regenerative agriculture (multispecies cover crops; no-till or strip-till/vertical till; and crop rotations) in a robust replicated plot design to quantify the impacts on soil carbon accrual (net carbon flux), soil microbial diversity, water use efficiency, soil health, forage nutrient density, and economic return. 
Link to website: https://www.csuchico.edu/regenerativeagriculture/research/soil-carbon-accrual.shtml