Courtney's research is broadly focused on how the chemistry and accessibility of soil organic matter influences its turnover and stabilization, and subsequently, how this impacts the functioning of natural and managed ecosystems.
Many of the global challenges we face (climate change, biodiversity loss, food security) are dependent upon soil processes, and her work examines current controls on soil carbon and nitrogen stability with the aim of predicting and managing the response of soils to global change scenarios. Her particular expertise lies in linking the quantity, accessibility, and chemical composition of soil carbon and nitrogen to microbial activity and community composition, using a variety of methods. Previous projects have focused plant-soil-microbe feedbacks in response along gradients of grassland and rangeland degradation (Australia and Texas), nutrient enrichment, and edaphic properties.
Professional Experience
2015 - present Research Microbiologist (post-doc), USGS, Menlo Park CA
2012 - 2015 Office of the Chief Executive Postdoctoral Fellow, CSIRO, Adelaide SA, Australia
2008 - 2012 Graduate Research and Teaching Assistant, Purdue University, West Lafayette IN
2006 - 2007 Undergraduate Research Assistant, Miami University, Oxford OH
2005 - Laboratory Intern, Case Western Reserve, Cleveland, OH
Education and Certifications
Ph.D., Purdue University, Earth, Atmospheric, and Planetary Sciences, 2012
B.A., Miami University (Ohio), Microbiology, 2007
Science and Products
Understanding Impacts of Sea-Level Rise and Land Management on Critical Coastal Marsh Habitat
Arctic Biogeochemical Response to Permafrost Thaw (ABRUPT)
Understanding Impacts of Sea-Level Rise and Land Management on Critical Coastal Marsh Habitat
Biogeochemistry of the Critical Zone: Origin and Fate of Organic Matter
Deconstructing the microbial necromass continuum to inform soil carbon sequestration
Response to ‘Stochastic and deterministic interpretation of pool models’
A combined microbial and ecosystem metric of carbon retention efficiency explains land cover-dependent soil microbial biodiversity–ecosystem function relationships
Linking decomposition rates of soil organic amendments to their chemical composition
From pools to flow: The PROMISE framework for new insights on soil carbon cycling in a changing world
Soil microbial communities and global change
Mineralogy dictates the initial mechanism of microbial necromass association
Biological and mineralogical controls over cycling of low molecular weight organic compounds along a soil chronosequence
Batch sorption data, respired CO2, extractable DOC, and Raman spectra collected from an incubation with microbial necromass on feldspar or amorphous aluminum hydroxide
Science and Products
- Science
Understanding Impacts of Sea-Level Rise and Land Management on Critical Coastal Marsh Habitat
To ensure successful restoration of coastal wetlands, WARC researchers will measure carbon cycling processes that indicate ecosystem health and sustainability.Arctic Biogeochemical Response to Permafrost Thaw (ABRUPT)
Warming and thawing of permafrost soils in the Arctic is expected to become widespread over the coming decades. Permafrost thaw changes ecosystem structure and function, affects resource availability for wildlife and society, and decreases ground stability which affects human infrastructure. Since permafrost soils contain about half of the global soil carbon (C) pool, the magnitude of C losses...Understanding Impacts of Sea-Level Rise and Land Management on Critical Coastal Marsh Habitat
Coastal wetlands are some of the most productive and valuable habitats in the world. Louisiana contains 40% of the coastal wetlands in the United States, which provide critical habitat for waterfowl and fisheries, as well as many other benefits, such as storm surge protection for coastal communities. In terms of ecosystem services, biological resource production, and infrastructure investments, thBiogeochemistry of the Critical Zone: Origin and Fate of Organic Matter
Changing temperature, precipitation, and land use intensification has resulted in global soil degradation. The accompanying loss of soil organic matter (SOM) decreases important soil health services. Soil organic matter is a major global pool of carbon; if SOM can be increased, soils can mitigate elevated atmospheric CO2. However, there are major knowledge gaps in SOM persistence. This project... - Publications
Deconstructing the microbial necromass continuum to inform soil carbon sequestration
Microbial necromass is a large, dynamic and persistent component of soil organic carbon, the dominant terrestrial carbon pool. Quantification of necromass carbon stocks and its susceptibility to global change is becoming standard practice in soil carbon research. However, the typical proxies used for necromass carbon do not reveal the dynamic nature of necromass carbon flows and transformations wiResponse to ‘Stochastic and deterministic interpretation of pool models’
We concur with Azizi‐Rad et al. (2021) that it is vital to critically evaluate and compare different soil carbon models, and we welcome the opportunity to further describe the unique contribution of the PROMISE model (Waring et al. 2020) to this literature. The PROMISE framework does share many features with established biogeochemical models, as our original manuscript highlighted in Table 1, andA combined microbial and ecosystem metric of carbon retention efficiency explains land cover-dependent soil microbial biodiversity–ecosystem function relationships
While soil organic carbon (C) is the foundation of productive and healthy ecosystems, the impact of the ecology of microorganisms on C-cycling remains unknown. We manipulated the diversity, applied here as species richness, of the microbial community present in similar soils on two contrasting land-covers—an adjacent pasture and forest—and observed the transformations of plant detritus and soil orLinking decomposition rates of soil organic amendments to their chemical composition
The stock of organic carbon contained within a soil represents the balance between inputs and losses. Inputs are defined by the ability of vegetation to capture and retain carbon dioxide, effects that management practices have on the proportion of captured carbon that is added to soil and the application organic amendments. The proportion of organic amendment carbon retained is defined by its rateFrom pools to flow: The PROMISE framework for new insights on soil carbon cycling in a changing world
Soils represent the largest terrestrial reservoir of organic carbon, and the balance between soil organic carbon (SOC) formation and loss will drive powerful carbon‐climate feedbacks over the coming century. To date, efforts to predict SOC dynamics have rested on pool‐based models, which assume classes of SOC with internally homogenous physicochemical properties. However, emerging evidence suggestSoil microbial communities and global change
Soils and soil microbial communities mediate the biogeochemical processes that underly ecosystem-level changes. This chapter examines why soils and soil microbial communities are important for understanding impacts and feedbacks to global change. It discusses the technological approaches and challenges that are at the frontiers of this research area. Global change impacts on microbial communitiesMineralogy dictates the initial mechanism of microbial necromass association
Soil organic matter (SOM) improves soil fertility and mitigates disturbance related to climate and land use change. Microbial necromass (the accumulated cellular residues of microorganisms) comprises the majority of soil C, yet the formation and persistence of necromass in relation to mineralogy is poorly understood. We tested whether soil minerals had different microbial necromass association mecBiological and mineralogical controls over cycling of low molecular weight organic compounds along a soil chronosequence
Low molecular weight organic compounds (LMWOC) represent a small but critical component of soil organic matter (SOM) for microbial growth and metabolism. The fate of these compounds is largely under microbial control, yet outside the cell, intrinsic soil properties can also significantly influence their turnover and retention. Using a chronosequence representing 1200 ka of pedogenic development, w - Data
Batch sorption data, respired CO2, extractable DOC, and Raman spectra collected from an incubation with microbial necromass on feldspar or amorphous aluminum hydroxide
These datasets are from an incubation experiment with a combination of two minerals (feldspar or amorphous aluminum hydroxide), one living species of bacteria (Escherichia coli), and one added form of C (Arthrobacter crystallopoietes necromass). We characterized the sorptive properties of the minerals with batch sorption experiments using four low molecular weight C substrates (glucose, oxalic aci