Joseph Blankinship

Interests

Teaching

Soil Ecology of Sustainable Systems (ENVS 300); Nutrient Dynamics in Soils (ENVS 502); Scientific Writing (ENVS 408)

Research

Soil biogeochemistry; microbial ecology; soil carbon sequestration, soil greenhouse gas production and consumption; soil aggregate stability; biocrusts; carbon-water-microbe interactions; plant-microbe interactions; ecosystem responses to climate change; biochar; sustainable and regenerative desert agriculture

Courses

Scholarly Contributions

Chapters

• Blankinship, J. C., & Hungate, B. A. (2006). Belowground food webs in a changing climate. In Agroecosystems In A Changing Climate(pp 117-150). CRC Press. doi:10.1201/9781420003826.ch5
• Blankinship, J., & Hungate, B. (2006). Belowground food webs in a changing climate. In AGROECOSYSTEMS IN A CHANGING CLIMATE(pp 117-150). CRC Press.

Journals/Publications

• Musa, N., Khan, K., Blankinship, J., Ijaz, S., Akram, Z., Alwahibi, M., Ali, M., & Yousra, M. (2024). Sorption-Desorption of Phosphorus on Manure- and Plant-Derived Biochars at Different Pyrolysis Temperatures. Sustainability (Switzerland), 16(7). doi:10.3390/su16072755
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  Sustainable phosphorus (P) management is essential to preventing mineral fertilizer losses, reducing water pollution, and addressing eutrophication issues. Phosphorus sorption and mobility are strongly influenced by the properties of biochar, which are determined by pyrolysis temperature and type of feedstock. This understanding is crucial for optimizing biochar application for soil nutrient management. Therefore, a batch sorption-desorption experiment was conducted to examine P sorption-desorption in plant-based (parthenium, corn cobs) and manure-based (farmyard manure, poultry manure) biochars prepared at both 400 °C and 600 °C. Manure-based biochars demonstrated higher P sorption at 400 °C, with less sorption at 600 °C, while plant-based counterparts exhibited lower sorption capacities. Phosphorus desorption, on the other hand, increased at 600 °C, particularly in manure-based biochars. The scanning electron microscopy (SEM) and Fourier-transform infrared spectra (FTIR) analysis suggested that a lower pyrolysis temperature (400 °C) enhances P sorption due to higher specific surface area and different functional groups. Additionally, the manure-based biochars, which were enriched with calcium (Ca) and magnesium (Mg), contributed to increased P sorption. In summary, P sorption is enhanced by a lower carbonization (400 °C) temperature. Although manure-based biochars excel in retaining P, their effectiveness is limited to shorter durations. In contrast, plant-based biochars showcase a prolonged capacity for P retention.
• Musa, N., Khan, K., Ijaz, S., Akram, Z., & Blankinship, J. (2022). Phosphorus sorption-desorption on manure- and plant-derived biochars at different pyrolysis temperatures. JOURNAL OF SOIL SCIENCE AND PLANT NUTRITION.
• Ball, K., Malik, A., Muscarella, C., & Blankinship, J. (2023). Irrigation alters biogeochemical processes to increase both inorganic and organic carbon in arid-calcic cropland soils. Soil Biology and Biochemistry, 187. doi:10.1016/j.soilbio.2023.109189
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  Irrigation in arid croplands is necessary to sustain crop growth, but with increasing water scarcity and population growth in drylands, irrigation systems may need to shift from flooding to dripping techniques to cope with increased water demand. Therefore, it is important to understand how irrigation drives organic and inorganic carbon dynamics in arid-calcic soils. This study on arid-calcic cropland soils assessed the influence of flood and subsurface drip irrigation on soil organic carbon (SOC) and soil inorganic carbon (SIC) formation as influenced by soil chemical properties and bacterial and fungal biomass. As well, these dynamics were assessed in an unmanaged/unirrigated desert soil. Under drip irrigation, SOC was significantly greater than under flood irrigation, but flood stored more SIC than drip irrigation and no irrigation. The observed SOC–SIC patterns were likely driven by calcium binding. Flood irrigation adds significantly more calcium and bicarbonate to the system, while leaching dissolved organic carbon (DOC). Under flood, calcium is likely more preferentially bound as calcium carbonate. Under drip irrigation, less water was added, calcium and SOC were maintained in the rooting zone where SOC may be stabilized via cation-mediated bridging. Despite higher SOC under drip, more total, and bacterial biomass were detected under flood than drip irrigation, which promoted fungal biomass. Bacterial biomass under flood irrigation may be contributing to microbial carbonate precipitation, supported by the greater presence of common bacterial groups known to contribute to this process, and significant positive relationships with calcium. This research emphasizes the importance of examining SOC and SIC dynamics from abiotic and biotic and particularly microbial perspectives; to optimize soil carbon storage in arid croplands.
• Blankinship, J. C., Bristol, D., Hassan, K., & Nielsen, U. N. (2023). Responses of nematode abundances to increased and reduced rainfall under field conditions: A meta‐analysis. Ecosphere, 14(1). doi:10.1002/ecs2.4364
• Hoglund, S., Rathke, S., & Blankinship, J. (2022). Effect of biochar application rate on soil water and fertilizer retention in a Sonoran Desert cropland soil. JOURNAL OF ARID ENVIRONMENTS.
• Hoglund, S., Rathke, S., Fidel, R., & Blankinship, J. (2023). Contrasting effects of biochar application rate in an alkaline desert cropland soil. Journal of Arid Environments, 215. doi:10.1016/j.jaridenv.2023.105011
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  Improving water and nutrient retention in desert croplands using soil organic amendments can be a major challenge because organic matter decomposes quickly under irrigated conditions in a hot climate. Biochar—a long-lasting carbon-rich soil organic amendment—has been proposed to improve soil water and nutrient retention, but only by carefully selecting an appropriate application rate. To better understand effects of biochar application rate on soil water and nutrient retention in desert croplands, we set up a mesocosm-scale experiment with biochar added at rates of 0, 19.8, 39.7, 79.4, 119.0, and 158.7 t ha−1 to an alkaline, sandy loam soil. After initial water retention measurements, we added fertilizer and then measured gaseous nitrogen losses as well as soil nitrate (NO3−) and phosphate (PO₄³⁻) leaching. Then, we measured biochar's effect on the soil's capacity to hold plant-available water (i.e., available water capacity, or AWC) using Tempe cells and a dewpoint potentiometer. We found contrasting effects of low and high biochar application rates. First, we found that applying a minimum of 79.4 t ha−1 biochar was necessary to improve soil water and PO₄³⁻ retention; application rates below 79.4 t ha−1 exacerbated PO₄³⁻ leaching whereas treatments above 79.4 t ha−1 improved AWC by up to 34% compared to the control treatment. While biochar application rate did not affect soil nitric oxide or ammonia emissions, we did find that low biochar application rates increased soil nitrous oxide emission while higher application rates reduced emission compared to soil with no biochar. Overall, we found that lower and higher rates of biochar application can have contrasting effects on soil water and nutrient retention in an alkaline, desert cropland soil. Therefore, farmers and other land managers must consider potential drawbacks of lower application rates and threshold responses of higher application rates prior to large-scale biochar use in arid agroecosystems.
• Marsh, C., Blankinship, J., & Hurteau, M. (2023). Effects of nurse shrubs and biochar on planted conifer seedling survival and growth in a high-severity burn patch in New Mexico, USA. Forest Ecology and Management, 537. doi:10.1016/j.foreco.2023.120971
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  The synergistic effects of widespread high-severity wildfire and anthropogenic climate change are driving large-scale vegetation conversion. In the southwestern United States, areas that were once dominated by conifer forests are now shrub- or grasslands after high-severity wildfire, an ecosystem conversion that could be permanent without human intervention. Yet, the reforestation of these landscapes is rarely successful, with a mean planted seedling survival of just 25 %. Given these low rates, we carried out a planting experiment to quantify the impacts of biochar as a soil amendment and shrubs as nurse plants on planted conifer seedling survival and growth following high-severity wildfire. We planted 1200 seedlings of three species (Pinus ponderosa, P. strobiformis, and Pseudotsuga menziesii) in a 2-ha area within the footprint of the Las Conchas fire in New Mexico, USA. We used four treatments: under shrubs, or in the open and with or without biochar in a full-factorial design. We found that planting tree seedlings underneath shrubs increased tree seedling survival by 46 % after 3 years, with some marginal evidence that shrubs inhibited seedling diameter growth (mean R2 = 0.08). The addition of biochar increased seedling survival by 11 % but had no effect on seedling growth. Our study suggests that planted seedling survival in post-wildfire areas can be increased by planting under shrubs in soil amended with biochar. The widespread adoption of these methods may improve the success rates of post-wildfire reforestation efforts in semi-arid areas, regaining some of the ecosystem services lost to high-severity wildfire.
• Mpanga, I., Neumann, G., Brown, J., Blankinship, J., Tronstad, R., & Idowu, O. (2023). Grape pomace's potential on semi-arid soil health enhances performance of maize, wheat, and grape crops. Journal of Plant Nutrition and Soil Science, 186(3). doi:10.1002/jpln.202200232
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  Background: Grape pomace (GP) is a by-product of wineries after filtering the grape juice for wine production. GP contains seeds, pulp, skin, and stalks with acidic properties, and it is normally composted before using as a soil amendment. However, composting GP requires more time, labor, and equipment; furthermore, composting loses some of the desirable organic acids for arid soils. The acidic properties of these organic acids and the plant nutrients in GP make it a desirable amendment for arid soils in both non-composted and composted forms. Aim: This study investigates the potential of directly applying GP as a soil amendment and its impact on arid soil health and plant performance. Methods: To test the potential of non-composted GP as a soil amendment, greenhouse and field studies were conducted by combining GP with existing management practices (manure application for soil used in the greenhouse study and fertigation for the field study) to assess the effects of GP on soil health and crop (maize, wheat, and grape) performance. Results: Adding 5% GP to an alkaline soil significantly increased maize and wheat growth and shoot nutrient concentrations in the greenhouse and grapes in the field (48% yield increase). The significance of GP on maize, wheat, and grapes was associated with soil nutrient enhancements (i.e., nutrients supplied, increase in organic matter and microbial biomass increase, reduction in pH, and better nutrient mobilization). Conclusion: GP has the potential for direct use as a soil amendment for soil and crop health improvement, especially in arid soils with high pH and limited soil organic matter.
• Blankinship, J. C., Ball, K. R., Leger, A. M., & Rathke, S. J. (2022). Mulch more so than compost improves soil health to reestablish vegetation in a semiarid rangeland. Restoration Ecology, 30(6). doi:10.1111/rec.13698
• Blankinship, J. C., Schiro, G., Chen, Y., & Barberán, A. (2022). Ride the dust: linking dust dispersal and spatial distribution of microorganisms across an arid landscape. Environmental Microbiology, 24(9), 4094-4107. doi:10.1111/1462-2920.15998
• Leger, A., Ball, K., Rathke, S., & Blankinship, J. (2022). Using mulch and compost to restore soil health and reestablish vegetation in a semiarid rangeland. RESTORATION ECOLOGY.
• Martyn, T. E., Barberán, A., Blankinship, J. C., Miller, M., Yang, B., Kline, A., & Gornish, E. S. (2022). Rock structures improve seedling establishment, litter catchment, fungal richness, and soil moisture in the first year after installation. Environmental Management, 70(Issue 1). doi:10.1007/s00267-022-01651-6
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  Grasslands are essential natural and agricultural ecosystems that encompass over one-third of global lands. However, land conversion and poor management have caused losses of these systems which contributed to a 10% reduction of net primary production, a 4% increase in carbon emissions, and a potential loss of US $42 billion a year. It is, therefore, important to restore, enhance and conserve these grasslands to sustain natural plant communities and the livelihoods of those that rely on them. We installed low cost rock structures (media lunas) to assess their ability to restore grasslands by slowing water flow, reducing erosion and improving plant establishment. Our treatments included sites with small and large rock structures that were seeded with a native seed mix as well as sites with no seed or rock and sites with only seed addition. We collected summer percent cover for plants, litter, and rock and spring seedling count data. We also collected soil for nutrient, moisture, and microbial analysis. Within the first year, we found no change in plant cover between rock structures of two rock sizes. We did find, however, an increase in soil moisture, litter, fungal richness, and spring seedling germination within the rock structures, despite a historic drought. This work demonstrates that rock structures can positively impact plants and soils of grasslands even within the first year. Our results suggest that managers should seriously consider employing these low-cost structures to increase short-term plant establishment and possibly, soil health, in grasslands.
• Martyn, T., Barberan, A., Blankinship, J., Miller, M., Yang, B., Kline, A., & Gornish, E. (2022). Rock structures improve seedling establishment, litter catchment, fungal richness, and soil moisture in the first year after installation. ENVIRONMENTAL MANAGEMENT, N/A.
• Mpanga, I., Blankinship, J., Tronstad, R. E., Neumann, G., & Idowu, J. (2022). Grape pomace enhances maize, wheat, and grape performance in semi-arid soils. Current Research in Sustainability.
• Schiro, G., Chen, Y., Blankinship, J., & Barberan, A. (2022). Ride the dust: Linking dust dispersal and spatial distribution of microorganisms across an arid landscape. ENVIRONMENTAL MICROBIOLOGY, N/A.
• Wood, S. A., & Blankinship, J. C. (2022). Making soil health science practical: guiding research for agronomic and environmental benefits. Soil Biology and Biochemistry, 172(Issue). doi:10.1016/j.soilbio.2022.108776
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  Defining what makes a “good” soil has long been of interest to soil scientists. Over the years, several conceptual frameworks have emerged to serve this purpose: tilth, soil fertility, soil quality, soil security, and soil health. There has been a growing body of research assessing how various management practices impact indicators of “good” soils. We argue that the growing body of research on soil health parameters has advanced our knowledge of how these indicators respond to land management, but produced little insight into how lands should be managed to increase environmental and agronomic benefits. We believe this lack of insight is due to under-emphasis of several knowledge areas: Is an increase in a soil health property good or bad? How much do desirable outcomes change when a soil property changes, and is the relationship between the two linear? Can land management change soil indicators by a sufficient magnitude to cause the desired change in outcome? And, what new indicators are needed to enable innovation in agricultural systems? Innovation in soil health measurements is important because the lack of practical insight into how to manage land risks dampening enthusiasm and innovation about the role soils can play in transitioning to sustainable food systems; it means that policy & practice risks moving forward without a strong evidence base.
• Wood, S., Wallenstein, M., & Blankinship, J. (2022). Making soil health science practical: Guiding research for agronomic and environmental benefits. SOIL BIOLOGY AND BIOCHEMISTRY.
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  For inclusion in Virtual Special Issue on biological and biochemical indicators of soil health
• Blankinship, J. C., Rasmussen, C., Heckman, K., Hicks Pries, C. E., Lawrence, C. R., Crow, S. E., Hoyt, A. M., Fromm, S. F., Shi, Z., Stoner, S., McGrath, C., Beem‐Miller, J., Berhe, A. A., Keiluweit, M., Marín‐Spiotta, E., Monroe, J. G., Plante, A. F., Schimel, J., Sierra, C. A., , Thompson, A., et al. (2021). Beyond bulk: Density fractions explain heterogeneity in global soil carbon abundance and persistence. Global Change Biology, 28(3), 1178-1196. doi:10.1111/gcb.16023
• Heckman, K., Hicks Pries, C. E., Lawrence, C. R., Rasmussen, C., Crow, S. E., Hoyt, A. M., von Fromm, S. F., Shi, Z., Stoner, S., McGrath, C., Beem-Miller, J., Berhe, A. A., Blankinship, J. C., Keiluweit, M., Marín-Spiotta, E., Monroe, J. G., Plante, A. F., Schimel, J., Sierra, C. A., , Thompson, A., et al. (2022). Beyond bulk: Density fractions explain heterogeneity in global soil carbon abundance and persistence. GLOBAL CHANGE BIOLOGY, 28(3), 1178-1196.
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  Understanding the controls on the amount and persistence of soil organic carbon (C) is essential for predicting its sensitivity to global change. The response may depend on whether C is unprotected, isolated within aggregates, or protected from decomposition by mineral associations. Here, we present a global synthesis of the relative influence of environmental factors on soil organic C partitioning among pools, abundance in each pool (mg C g  soil), and persistence (as approximated by radiocarbon abundance) in relatively unprotected particulate and protected mineral-bound pools. We show that C within particulate and mineral-associated pools consistently differed from one another in degree of persistence and relationship to environmental factors. Soil depth was the best predictor of C abundance and persistence, though it accounted for more variance in persistence. Persistence of all C pools decreased with increasing mean annual temperature (MAT) throughout the soil profile, whereas persistence increased with increasing wetness index (MAP/PET) in subsurface soils (30-176 cm). The relationship of C abundance (mg C g  soil) to climate varied among pools and with depth. Mineral-associated C in surface soils (
• Lawrence, C., Beem-Miller, J., Hoyt, A., Monroe, G., Sierra, C., Stoner, S., Heckman, K., Blankinship, J., Crow, S., McNicol, G., Trumbore, S., Levine, P., Vinduskova, O., Todd-Brown, K., Rasmussen, C., Hicks Pries, C., Schadel, C., McFarlane, K., Doetterl, S., & Hatte, C. (2020). An open-source database for the synthesis of soil radiocarbon data: International Soil Radiocarbon Database (ISRaD) version 1.0. EARTH SYSTEM SCIENCE DATA, 12, 61-76.
• R. Lawrence, C., R. Lawrence, C., Beem-Miller, J., Beem-Miller, J., M. Hoyt, A., M. Hoyt, A., Monroe, G., Monroe, G., A. Sierra, C., A. Sierra, C., Stoner, S., Stoner, S., Heckman, K., Heckman, K., C. Blankinship, J., C. Blankinship, J., E. Crow, S., E. Crow, S., McNicol, G., , McNicol, G., et al. (2020). An open-source database for the synthesis of soil radiocarbon data: International Soil Radiocarbon Database (ISRaD) version 1.0. Earth System Science Data, 12(Issue 1). doi:10.5194/essd-12-61-2020
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  Radiocarbon is a critical constraint on our estimates of the timescales of soil carbon cycling that can aid in identifying mechanisms of carbon stabilization and destabilization and improve the forecast of soil carbon response to management or environmental change. Despite the wealth of soil radiocarbon data that have been reported over the past 75 years, the ability to apply these data to global-scale questions is limited by our capacity to synthesize and compare measurements generated using a variety of methods. Here, we present the International Soil Radiocarbon Database (ISRaD; http://soilradiocarbon.org, last access: 16 December 2019), an open-source archive of soil data that include reported measurements from bulk soils, distinct soil carbon pools isolated in the laboratory by a variety of soil fractionation methods, samples of soil gas or water collected interstitially from within an intact soil profile, CO2 gas isolated from laboratory soil incubations, and fluxes collected in situ from a soil profile. The core of ISRaD is a relational database structured around individual datasets (entries) and organized hierarchically to report soil radiocarbon data, measured at different physical and temporal scales as well as other soil or environmental properties that may also be measured and may assist with interpretation and context. Anyone may contribute their own data to the database by entering it into the ISRaD template and subjecting it to quality assurance protocols. ISRaD can be accessed through (1) a web-based interface, (2) an R package (ISRaD), or (3) direct access to code and data through the GitHub repository, which hosts both code and data. The design of ISRaD allows for participants to become directly involved in the management, design, and application of ISRaD data. The synthesized dataset is available in two forms: the original data as reported by the authors of the datasets and an enhanced dataset that includes ancillary geospatial data calculated within the ISRaD framework. ISRaD also provides data management tools in the ISRaD-R package that provide a starting point for data analysis; as an open-source project, the broader soil community is invited and encouraged to add data, tools, and ideas for improvement. As a whole, ISRaD provides resources to aid our evaluation of soil dynamics across a range of spatial and temporal scales. The ISRaD v1.0 dataset is archived and freely available at https://doi.org/10.5281/zenodo.2613911 (Lawrence et al., 2019).
• Todd-brown, K. E., Todd-brown, K. E., Thompson, A. J., Thompson, A. J., Wagai, R., Wagai, R., Vinduskova, O., Vinduskova, O., Vaughn, L. J., Vaughn, L. J., Trumbore, S. E., Trumbore, S. E., Treat, C. C., Treat, C. C., Torn, M. S., Torn, M. S., Todd-brown, K., Todd-brown, K., Thompson, A., , Thompson, A., et al. (2019). An open source database for the synthesis of soil radiocarbon data: ISRaD version 1.0. Earth System Science Data Discussions, 12(1), 61-76. doi:10.3929/ethz-b-000385703
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  Abstract. Radiocarbon is a critical constraint on our estimates of the timescales of soil carbon cycling that can aid in identifying mechanisms of carbon stabilization and destabilization, and improve forecast of soil carbon response to management or environmental change. Despite the wealth of soil radiocarbon data that has been reported over the past 75 years, the ability to apply these data to global scale questions is limited by our capacity to synthesis and compare measurements generated using a variety of methods. Here we describe the International Soil Radiocarbon Database (ISRaD, soilradiocarbon.org ), an open-source archive of soils data that include data from bulk soils, or whole-soils ; distinct soil carbon pools isolated in the laboratory by a variety of soil fractionation methods; samples of soil gas or water collected interstitially from within an intact soil profile; CO2 gas isolated from laboratory soil incubations; and fluxes collected in situ from a soil surface. The core of ISRaD is a relational database structured around individual datasets (entries) and organized hierarchically to report soil radiocarbon data, measured at different physical and temporal scales, as well as other soil or environmental properties that may also be measured at one or more levels of the hierarchy that may assist with interpretation and context. Anyone may contribute their own data to the database by entering it into the ISRaD template and subjecting it to quality assurance protocols. ISRaD can be accessed through: (1) a web-based interface, (2) an R package (ISRaD), or (3) direct access to code and data through the GitHub repository, which hosts both code and data. The design of ISRaD allows for participants to become directly involved in the management, design, and application of ISRaD data. The synthesized dataset is available in two forms: the original data as reported by the authors of the datasets; and an enhanced dataset that includes ancillary geospatial data calculated within the ISRaD framework. ISRaD also provides data management tools in the ISRaD-R package that provide a starting point for data analysis. This community-based dataset and platform for soil radiocarbon and a wide array of additional soils data information in soils where data are easy to contribute and the community is invited to add tools and ideas for improvement. As a whole, ISRaD provides resources that can aid our evaluation of soil dynamics and improve our understanding of controls on soil carbon dynamics across a range of spatial and temporal scales. The ISRaD v1.0 dataset (Lawrence et al., 2019) is archived and freely available at https://doi.org/10.5281/zenodo.2613911 .
• Blankinship, J. C., & Schimel, J. P. (2018). Biotic versus abiotic controls on bioavailable soil organic carbon. Soil Systems, 2(Issue 1). doi:10.3390/soilsystems2010010
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  Processes controlling microbial access to soil organic matter are critical for soil nutrient cycling and C stabilization. The bioavailability of soil organic matter partly depends on the rate that substrates become water-soluble, which is determined by some combination of biological, biochemical, and purely abiotic processes. Our goal was to unravel these biotic and abiotic processes to better understand mechanisms controlling the dynamics of bioavailable soil organic carbon (SOC). We sampled soils in a California annual grassland from manipulated plots with and without plants to help distinguish bioavailable SOC generated from mineral-associated organic matter versus from plant detritus (i.e., the “light fraction”). In the laboratory, soils were incubated for 8 months under all possible combinations of three levels of moisture and two levels of microbial biomass using continuous chloroform sterilization. We measured cumulative carbon dioxide (CO2) production and the net change in soil water-extractable organic C (WEOC) to quantify C that was accessed biologically or biochemically. Under the driest conditions, microbes appeared to primarily access WEOC from recent plant C, with the other half of CO2 production explained by extracellular processes. These results suggest that dry, uncolonized conditions promote the adsorption of WEOC onto mineral surfaces. Under wetter conditions, microbial access increased by two orders of magnitude, with a large concomitant decrease in WEOC, particularly in soils without plant inputs from the previous growing season. The largest increase in WEOC occurred in wet sterilized soil, perhaps because exoenzymes and desorption continued solubilizing C but without microbial consumption. A similar amount of WEOC accumulated in wet sterilized soil whether plants were present or not, suggesting that desorption of mineral-associated C was the abiotic WEOC source. Based on these results, we hypothesize that dry-live and wet-uncolonized soil microsites are sources of bioavailable SOC, whereas wet-live and dry-uncolonized microsites are sinks.
• Blankinship, J. C., Berhe, A. A., Crow, S. E., Druhan, J. L., Heckman, K. A., Keiluweit, M., Lawrence, C. R., Marin-Spiotta, E., Plante, A. F., Rasmussen, C., Schimel, J. P., Sierra, C. A., Schaedel, C., Thompson, A., Wagai, R., & Wieder, W. R. (2018). Improving understanding of soil organic matter dynamics by triangulating theories, measurements, and models. BIOGEOCHEMISTRY, 140, 1-13. doi:10.1007/s10533-018-0478-2
• Blankinship, J. C., Berhe, A. A., Crow, S. E., Druhan, J. L., Heckman, K. A., Keiluweit, M., Lawrence, C. R., Marín-Spiotta, E., Plante, A. F., Rasmussen, C., Schädel, C., Schimel, J. P., Sierra, C. A., Thompson, A., Wagai, R., & Wieder, W. R. (2018). Improving understanding of soil organic matter dynamics by triangulating theories, measurements, and models. Biogeochemistry, 140(Issue 1). doi:10.1007/s10533-018-0478-2
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  Soil organic matter (SOM) turnover increasingly is conceptualized as a tension between accessibility to microorganisms and protection from decomposition via physical and chemical association with minerals in emerging soil biogeochemical theory. Yet, these components are missing from the original mathematical models of belowground carbon dynamics and remain underrepresented in more recent compartmental models that separate SOM into discrete pools with differing turnover times. Thus, a gap currently exists between the emergent understanding of SOM dynamics and our ability to improve terrestrial biogeochemical projections that rely on the existing models. In this opinion paper, we portray the SOM paradigm as a triangle composed of three nodes: conceptual theory, analytical measurement, and numerical models. In successful approaches, we contend that the nodes are connected—models capture the essential features of dominant theories while measurement tools generate data adequate to parameterize and evaluate the models—and balanced—models can inspire new theories via emergent behaviors, pushing empiricists to devise new measurements. Many exciting advances recently pushed the boundaries on one or more nodes. However, newly integrated triangles have yet to coalesce. We conclude that our ability to incorporate mechanisms of microbial decomposition and physicochemical protection into predictions of SOM change is limited by current disconnections and imbalances among theory, measurement, and modeling. Opportunities to reintegrate the three components of the SOM paradigm exist by carefully considering their linkages and feedbacks at specific scales of observation.
• Blankinship, J. C., Homyak, P. M., Slessarev, E. W., Schaeffer, S. M., Manzoni, S., & Schimel, J. P. (2018). Effects of altered dry season length and plant inputs on soluble soil carbon. Ecology, 99(10), 2348-2362. doi:10.1002/ecy.2473
• Blankinship, J. C., McCorkle, E. P., Meadows, M. W., & Hart, S. C. (2018). Quantifying the legacy of snowmelt timing on soil greenhouse gas emissions in a seasonally dry montane forest. GLOBAL CHANGE BIOLOGY, 24, 5933-5947.
• Blankinship, J. C., McCorkle, E. P., Meadows, M. W., & Hart, S. C. (2018). Quantifying the legacy of snowmelt timing on soil greenhouse gas emissions in a seasonally dry montane forest. Global Change Biology, 24(Issue 12). doi:10.1111/gcb.14471
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  The release of water during snowmelt orchestrates a variety of important belowground biogeochemical processes in seasonally snow-covered ecosystems, including the production and consumption of greenhouse gases (GHGs) by soil microorganisms. Snowmelt timing is advancing rapidly in these ecosystems, but there is still a need to isolate the effects of earlier snowmelt on soil GHG fluxes. For an improved mechanistic understanding of the biogeochemical effects of snowmelt timing during the snow-free period, we manipulated a high-elevation forest that typically receives over two meters of snowfall but little summer precipitation to influence legacy effects of snowmelt timing. We altered snowmelt rates for two years using black sand to accelerate snowmelt and white fabric to postpone snowmelt, thus creating a two- to three-week disparity in snowmelt timing. Soil microclimate and fluxes of carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) were monitored weekly to monthly during the snow-free period. Microbial abundances were estimated by potential assays near the end of each snow-free period. Although earlier snowmelt caused soil drying, we found no statistically significant effects (p < 0.05) of altered snowmelt timing on fluxes of CO2 or N2O, or soil microbial abundances. Soil CH4 fluxes, however, did respond to snowmelt timing, with 18% lower rates of CH4 uptake in the earlier snowmelt treatment, but only after a dry winter. Cumulative CO2 emission and CH4 uptake were 43% and 88% greater, respectively, after the dry winter. We conclude that soil GHG fluxes can be surprisingly resistant to hydrological changes associated with earlier snowmelt, likely because of persistent moisture and microbial activities in deeper mineral soils. As a result, a drier California in the future may cause seasonally snow-covered soils in the Sierra Nevada to emit more GHGs, not less.
• Blankinship, J., & Schimel, J. (2018). Biotic versus abiotic controls on bioavailable soil organic carbon. SOIL SYSTEMS, 2, 10. doi:10.3390/soilsystems2010010
• Harden, J. W., Hugelius, G., Ahlstrom, A., Blankinship, J. C., Bond-Lamberty, B., Lawrence, C. R., Loisel, J., Malhotra, A., Jackson, R. B., Ogle, S., Phillips, C., Ryals, R., Todd-Brown, K., Vargas, R., Vergara, S. E., Cotrufo, F., Keiluweit, M., Heckman, K. A., Crow, S. E., , Silver, W. L., et al. (2018). Networking our science to characterize the state, vulnerabilities, and management opportunities of soil organic matter. GLOBAL CHANGE BIOLOGY, 24, e705-e718.
• Homyak, P. M., Blankinship, J. C., Slessarev, E. W., Schaeffer, S. M., Manzoni, S., & Schimel, J. P. (2018). Effects of altered dry season length and plant inputs on soluble soil carbon. ECOLOGY, 99, 2348-2362.
• Marchus, K. A., Blankinship, J. C., & Schimel, J. P. (2018). Environmental controls on extracellular polysaccharide accumulation in a California grassland soil. SOIL BIOLOGY AND BIOCHEMISTRY, 125, 86-92.
• Marchus, K. A., Blankinship, J. C., & Schimel, J. P. (2018). Environmental controls on extracellular polysaccharide accumulation in a California grassland soil. Soil Biology and Biochemistry, 125(Issue). doi:10.1016/j.soilbio.2018.07.009
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  Areas with Mediterranean climate regimes, such as California, have cool wet winter growing seasons and hot dry summers. Summer is a time of stress for plants, yet soil microbes survive and biochemical processes continue. One mechanism soil microorganisms might use to survive drought is to produce extracellular polysaccharides (EPSac). We hypothesized that in dry soils, pools of microbial EPSac would therefore increase, but that this increase would depend on having carbon available from fresh plant inputs. We manipulated plant cover and dry season length and measured soil saccharides in a seasonally dry California grassland soil; we evaluated total sugars as well as the mix of sugars present in the soil. Soil cores were collected monthly from July 2014 to February 2015. Sugar residues were analyzed using Gas Chromatography—Mass Spectroscopy (GC-MS). Drier soils showed larger pools of sugar residues; these residues decreased as moisture increased across sample dates and treatments. Plant removal only slightly reduced soil saccharide levels. However, the pools of individual saccharides varied only modestly across all treatments and dates, and correlated with total microbial biomass, suggesting that extracellular polysaccharides may be a constitutive response to survival in soil, rather than an inducible response to dry conditions.
• Rasmussen, C., Heckman, K., Wieder, W. R., Keiluweit, M., Lawrence, C. R., Berhe, A. A., Blankinship, J. C., Crow, S. E., Druhan, J. L., Hicks Pries, C. E., Marin-Spiotta, E., Plante, A. F., Schädel, C., Schimel, J. P., Sierra, C. A., Thompson, A., & Wagai, R. (2018). Beyond clay: towards an improved set of variables for predicting soil organic matter content. Biogeochemistry, 137(Issue 3). doi:10.1007/s10533-018-0424-3
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  Improved quantification of the factors controlling soil organic matter (SOM) stabilization at continental to global scales is needed to inform projections of the largest actively cycling terrestrial carbon pool on Earth, and its response to environmental change. Biogeochemical models rely almost exclusively on clay content to modify rates of SOM turnover and fluxes of climate-active CO2 to the atmosphere. Emerging conceptual understanding, however, suggests other soil physicochemical properties may predict SOM stabilization better than clay content. We addressed this discrepancy by synthesizing data from over 5,500 soil profiles spanning continental scale environmental gradients. Here, we demonstrate that other physicochemical parameters are much stronger predictors of SOM content, with clay content having relatively little explanatory power. We show that exchangeable calcium strongly predicted SOM content in water-limited, alkaline soils, whereas with increasing moisture availability and acidity, iron- and aluminum-oxyhydroxides emerged as better predictors, demonstrating that the relative importance of SOM stabilization mechanisms scales with climate and acidity. These results highlight the urgent need to modify biogeochemical models to better reflect the role of soil physicochemical properties in SOM cycling.
• Rasmussen, C., Heckman, K., Wieder, W. R., Keiluweit, M., Lawrence, C. R., Berhe, A. A., Blankinship, J. C., Crow, S. E., Druhan, J. L., Hicks-Pries, C. E., Marin-Spiotta, E., Plante, A. F., Schaedel, C., Schimel, J. P., Sierra, C. A., Thompson, A., & Wagai, R. (2018). Beyond clay: towards an improved set of variables for predicting soil organic matter content. BIOGEOCHEMISTRY, 137, 297-306.
• Blankinship, J. C., Harden, J. W., Hugelius, G., Ahlström, A., Bond‐Lamberty, B., Lawrence, C. R., Loisel, J., Malhotra, A., Jackson, R. B., Ogle, S., Phillips, C., Ryals, R., Todd‐Brown, K., Vargas, R., Vergara, S. E., Cotrufo, M. F., Keiluweit, M., Heckman, K. A., Crow, S. E., , Silver, W. L., et al. (2017). Networking our science to characterize the state, vulnerabilities, and management opportunities of soil organic matter. Global Change Biology, 24(2). doi:10.1111/gcb.13896
• Carey, C. J., Blankinship, J. C., Eviner, V. T., Malmstrom, C. M., & Hart, S. C. (2017). Invasive plants decrease microbial capacity to nitrify and denitrify compared to native California grassland communities. BIOLOGICAL INVASIONS, 19(10), 2941-2957.
• Carey, C. J., Blankinship, J. C., Eviner, V. T., Malmstrom, C. M., & Hart, S. C. (2017). Invasive plants decrease microbial capacity to nitrify and denitrify compared to native California grassland communities. Biological Invasions, 19(Issue 10). doi:10.1007/s10530-017-1497-y
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  Exotic plant invasions are a major driver of global environmental change that can significantly alter the availability of limiting nutrients such as nitrogen (N). Beginning with European colonization of California, native grasslands were replaced almost entirely by annual exotic grasses, many of which are now so ubiquitous that they are considered part of the regional flora (“naturalized”). A new wave of invasive plants, such as Aegilops triuncialis (Barb goatgrass) and Elymus caput-medusae (Medusahead), continue to spread throughout the state today. To determine whether these new-wave invasive plants alter soil N dynamics, we measured inorganic N pools, nitrification and denitrification potentials, and possible mediating factors such as microbial biomass and soil pH in experimental grasslands comprised of A. triuncialis and E. caput-medusae. We compared these measurements with those from experimental grasslands containing: (1) native annuals and perennials and (2) naturalized exotic annuals. We found that A. triuncialis and E. caput-medusae significantly reduced ion-exchange resin estimates of nitrate (NO3 −) availability as well as nitrification and denitrification potentials compared to native communities. Active microbial biomass was also lower in invaded soils. In contrast, potential measurements of nitrification and denitrification were similar between invaded and naturalized communities. These results suggest that invasion by A. triuncialis and E. caput-medusae may significantly alter the capacity for soil microbial communities to nitrify or denitrify, and by extension alter soil N availability and rates of N transformations during invasion of remnant native-dominated sites.
• Harden, J., Hugelius, G., Ahlstrom, A., Blankinship, J., Bond-Lamberty, B., Lawrence, C., Loisel, J., Malhotra, A., Jackson, R., Ogle, S., Phillips, C., Ryals, R., Todd-Brown, K., Vargas, R., Vergara, S., Cotrufo, F., Keiluweit, M., Heckman, K., Crow, S., , Silver, W., et al. (2017). Networking our science to characterize the state, vulnerabilities, and management opportunities of soil organic matter. GLOBAL CHANGE BIOLOGY. doi:10.1111/gcb.13896
• Leitner, S., Homyak, P. M., Blankinship, J. C., Eberwein, J., Jenerette, G. D., Zechmeister-Boltenstern, S., & Schimel, J. P. (2017). Linking NO and N2O emission pulses with the mobilization of mineral and organic N upon rewetting dry soils. SOIL BIOLOGY & BIOCHEMISTRY, 115, 461-466.
• Leitner, S., Homyak, P. M., Blankinship, J. C., Eberwein, J., Jenerette, G. D., Zechmeister-Boltenstern, S., & Schimel, J. P. (2017). Linking NO and N2O emission pulses with the mobilization of mineral and organic N upon rewetting dry soils. Soil Biology and Biochemistry, 115(Issue). doi:10.1016/j.soilbio.2017.09.005
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  Drying and rewetting of soils triggers a cascade of physical, chemical, and biological processes; understanding these responses to varying moisture levels becomes increasingly important in the context of changing precipitation patterns. When soils dry and water content decreases, diffusion is limited and substrates can accumulate. Upon rewetting, these substrates are mobilized and can energize hot moments of intense biogeochemical cycling, leading to pulses of trace gas emissions. Until recently, it was difficult to follow the rewetting dynamics of nutrient cycling in the field without physically disturbing the soil. Here we present a study that combines real-time trace gas measurements with high-resolution measurements of diffusive nutrient fluxes in intact soils. Our goal was to distinguish the contribution of different inorganic and organic nitrogen (N) forms to the rewetting substrate flush and the production of nitric oxide (NO) and nitrous oxide (N2O). Diffusive flux of N-bearing substrates (NO2−, NO3−, NH4+ and amino acids) was determined in situ in hourly resolution using a microdialysis approach. We conducted an irrigation experiment in a semi-arid California grassland at the end of the dry season, and followed soil N flux and N trace gas emissions over the course of 30 h post-wetting. Upon rewetting, both inorganic and organic N diffused through the soil, with inorganic N contributing most to the rewetting N flush. Emissions of NO and N2O rapidly increased and remained elevated for the duration of our measurements, whereas diffusive soil N flux was characterized by large temporal variation. Immediately after rewetting, NO3− contributed 80% to the total diffusive N flux but was consumed rapidly, possibly due to fast microbial uptake or denitrification. Ammonium flux contributed only ∼10% to the initial diffusive N flux, but it dominated total N diffusion 27 h post-wetting, coinciding with peak N-gas emissions. This suggests nitrification may control most of the N trace gases produced during the late stages of a rewetting pulse. Nitrite contributed only 1% to total N diffusion and did not show a clear temporal pattern. Amino acids contributed roughly as much as NH4+ to the initial diffusive N flux, but the organic N pulse was short-lived, indicating that organic N did not contribute substantially to N-gas formation shortly after rewetting at our study site. Our results support the hypothesis that in semi-arid environments N-bearing substrates concentrate during dry periods and, upon rewetting, can lead to pulses of NO and N2O when they react chemically or are transformed by microorganisms.
• Schimel, J., Becerra, C. A., & Blankinship, J. (2017). Estimating decay dynamics for enzyme activities in soils from different ecosystems. SOIL BIOLOGY & BIOCHEMISTRY, 114, 5-11.
• Schimel, J., Becerra, C. A., & Blankinship, J. (2017). Estimating decay dynamics for enzyme activities in soils from different ecosystems. Soil Biology and Biochemistry, 114(Issue). doi:10.1016/j.soilbio.2017.06.023
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  Extracellular enzymes in soil are central to the decomposition of plant and microbial detritus and they are increasingly incorporated into soil biogeochemical models as drivers of detritus breakdown. In enzyme-driven models, a critical parameter is the functional lifespan of the enzymes, yet this is poorly constrained by experimental data. We evaluated how long soil enzymes remain active in five soils spanning from arctic tussock tundra to a tropical forest/grassland soil. We incubated soils under continuous fumigation with CHCl3 vapor to kill microbes and prevent the synthesis of new enzymes. We monitored the activities of six hydrolytic and two oxidative enzymes over a 12-week incubation. Initial activities of the various soil enzymes varied substantially across the ecosystems; they were generally highest (per gram soil) in the tussock tundra, followed by temperate hardwood forest, grassland, tropical forest/grassland, and then chaparral. In tussock tundra organic soil, activities of all enzymes decreased rapidly following first-order decay curves; the half-lives of enzyme activity were typically several weeks. In the mineral soils, the time course of loss of hydrolytic enzyme activities could always be described by a first-order decay curve, but in many cases, activity could equally be described by a zero-order, linear, decay function because the rate of loss was slow. Although α-glucosidase lost activity rapidly, for other enzymes substantial activity remained even after 12 weeks of incubation. This likely resulted from stabilization by mineral surfaces, stabilization that might constrain activity against native polymeric substrates. Measured turnover rate constants fell within the broad range that model have used, but that range remains exceedingly broad.
• Blankinship, J. C., Fonte, S. J., Six, J., & Schimel, J. P. (2016). Plant versus microbial controls on soil aggregate stability in a seasonally dry ecosystem. GEODERMA, 272, 39-50.
• Blankinship, J. C., Fonte, S. J., Six, J., & Schimel, J. P. (2016). Plant versus microbial controls on soil aggregate stability in a seasonally dry ecosystem. Geoderma, 272(Issue). doi:10.1016/j.geoderma.2016.03.008
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  The formation of water-stable macroaggregates in soil is beneficial for many reasons, including carbon (C) sequestration, nutrient retention, and erosion control. A mix of biotic (e.g., plant C input, microbial activity) and abiotic factors (e.g., water, mineral interactions) contribute to form macroaggregates. However, in order to better model and manage soil macroaggregates, we need to know more about the relative contributions of these mechanisms. Previous experiments to separate microbial and abiotic mechanisms have been hampered by the need to add sterilant dissolved in water, thus limiting our ability to draw conclusions about the role of soil moisture in controlling aggregation and preventing conclusions about dry soil. Our first goal was to quantify the contribution of plant growth (and fresh plant C inputs) by continuously removing plants for 2 years in a seasonally dry grassland. Our second goal was to quantify microbial vs. abiotic contributions to macroaggregate formation under a range of soil moisture conditions by using chloroform vapor to sterilize soil without adding water or destroying soil structure. In the field, regardless of dry season length, removing plants reduced the average size of soil aggregates by 22-33%, which was primarily driven by a shift from large macroaggregates (2-9 mm diameter) to small macroaggregates (0.25-2 mm). In the laboratory, in sterile soils macroaggregate production increased with the moisture content. The resulting physicogenic aggregates appeared planar and angular at both macro- and micro-scales. In contrast, biogenic aggregates were formed most at intermediate moisture levels and were spherical. Our results suggest that-even in dry climates-soil macroaggregates are preserved by the presence of even dead plant roots, but are engineered by live microbes.
• Homyak, P. M., Blankinship, J. C., Marchus, K., Lucero, D. M., Sickman, J. O., & Schimel, J. P. (2016). Aridity and plant uptake interact to make dryland soils hotspots for nitric oxide (NO) emissions. PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 113(19), E2608-E2616.
• Duval, B. D., Blankinship, J. C., Dijkstra, P., & Hungate, B. A. (2015). CO2 effects on plant nutrient concentration depend on plant functional group and available nitrogen: a meta-analysis (Retraction of vol 213, pg 505, 2012). PLANT ECOLOGY, 216(12), 1675-1675.
• Blankinship, J. C., & Hart, S. C. (2014). Hydrological control of greenhouse gas fluxes in a Sierra Nevada subalpine meadow. ARCTIC ANTARCTIC AND ALPINE RESEARCH, 46(2), 355-364.
• Blankinship, J. C., Becerra, C. A., Schaeffer, S. M., & Schimel, J. P. (2014). Separating cellular metabolism from exoenzyme activity in soil organic matter decomposition. SOIL BIOLOGY & BIOCHEMISTRY, 71, 68-75.
• Blankinship, J. C., Becerra, C. A., Schaeffer, S. M., & Schimel, J. P. (2014). Separating cellular metabolism from exoenzyme activity in soil organic matter decomposition. Soil Biology and Biochemistry, 71(Issue). doi:10.1016/j.soilbio.2014.01.010
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  Soil organic matter (SOM) decomposes both inside and outside of cells. Cellular metabolism and extracellular depolymerization normally operate simultaneously in soil but are difficult to separate in practice. To learn more about the extracellular component of SOM decomposition, we sterilized a semiarid annual grassland soil to inhibit cellular metabolism, and then assayed cell viability, exoenzyme activities, and pathways of carbon dioxide (CO2) emission. Chloroform (CHCl3) fumigation was intended to disrupt cellular activities while leaving biochemical processes intact. Gamma (γ) irradiation and autoclaving were intended to disrupt both cellular and extracellular biochemical processes while leaving abiotic processes intact. We measured the potential activities of eight enzymes (six hydrolytic, two oxidative) and CO2 emission induced by seven substrates (glucose, three amino acids, three tricarboxylic acid [TCA] cycle intermediates). We found that all three sterilization techniques clearly disrupted cellular metabolism. Chloroform and irradiation decreased cultivable cell counts by 2-3 orders of magnitude, inhibited CO2 emission pathways associated with glucose and amino acids, and decreased the hydrolytic activities of α-glucosidase and xylosidase by 72-82%. The other hydrolytic enzymes (β-glucosidase, cellobiohydrolase, NAGase, phosphatase) were less sensitive to both CHCl3 and irradiation. All hydrolytic activities that we assayed were inhibited by autoclaving, indicating that biochemical reactions and other extracellular processes drive hydrolytic SOM decomposition. Oxidative activities, on the other hand, did not stop after autoclaving or even combusting at 500°C. This supports other studies which have found that mineral catalysts partly drive oxidative SOM decomposition. Unexpectedly, CO2 emission from TCA intermediates decreased by only 26-47% after sterilization suggesting that the required dehydrogenase enzymes for decarboxylation are still active when cells are dead but relatively intact. Because CHCl3 had slightly smaller effects on exoenzyme activities compared to irradiation, and because it may be continuously applied, limiting the potential for recolonization and regrowth (unlike irradiation), we suggest it is an adequate and more accessible method for separating the activity of exoenzymes from cellular metabolism under realistic soil conditions. © 2014 .
• Blankinship, J. C., Meadows, M. W., Lucas, R. G., & Hart, S. C. (2014). Snowmelt timing alters shallow but not deep soil moisture in the Sierra Nevada. WATER RESOURCES RESEARCH, 50(2), 1448-1456.
• Blankinship, J. C., Meadows, M. W., Lucas, R. G., & Hart, S. C. (2014). Snowmelt timing alters shallow but not deep soil moisture in the Sierra Nevada. Water Resources Research, 50(Issue 2). doi:10.1002/2013wr014541
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  Roughly one-third of the Earth's land surface is seasonally covered by snow. In many of these ecosystems, the spring snowpack is melting earlier due to climatic warming and atmospheric dust deposition, which could greatly modify soil water resources during the growing season. Though snowmelt timing is known to influence soil water availability during summer, there is little known about the depth of the effects and how long the effects persist. We therefore manipulated the timing of seasonal snowmelt in a high-elevation mixed-conifer forest in a Mediterranean climate during consecutive wet and dry years. The snow-all-gone (SAG) date was advanced by 6 days in the wet year and 3 days in the dry year using black sand to reduce the snow surface albedo. To maximize variation in snowmelt timing, we also postponed the SAG date by 8 days in the wet year and 16 days in the dry year using white fabric to shade the snowpack from solar radiation. We found that deeper soil water (30-60 cm) did not show a statistically significant response to snowmelt timing. Shallow soil water (0-30 cm), however, responded strongly to snowmelt timing. The drying effect of accelerated snowmelt lasted 2 months in the 0-15 cm depth and at least 4 months in the 15-30 cm depth. Therefore, the legacy of snowmelt timing on soil moisture can persist through dry periods, and continued earlier snowmelt due to climatic warming and windblown dust could reduce near-surface water storage and availability to plants and soil biota. Key Points The hydrological signal of snowmelt timing was strongest in shallow soil Effects of snowmelt timing on soil moisture lasted 2-4 months Advancing snowmelt timing by 2-3 weeks depleted shallow soil water by one third © 2014. American Geophysical Union. All Rights Reserved.
• Blankinship, J., & Hart, S. (2014). Hydrological control of greenhouse gas fluxes in a Sierra Nevada subalpine meadow. Arctic, Antarctic, and Alpine Research, 46(Issue 2). doi:10.1657/1938-4246-46.2.355
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  Alpine and subalpine meadows are often hotspots of water availability and biodiversity in montane landscapes, but we know little about whether these attributes also make meadows hotspots of greenhouse gas (GHG) emission. Furthermore, many of these meadows will likely become drier during the growing season in the future because of less precipitation, earlier timing of snowmelt, and increased evapotranspiration associated with climatic warming. To evaluate the potential effects of soil drying on GHG emission, we studied a soil moisture gradient in a Sierra Nevada subalpine meadow in California. Our objectives were: (1) to assess the strength of hydrological control for soil carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) fluxes both earlier and later in the growing season; and (2) to quantify the contribution of CH4 and N2O to net GHG emission. The replicated gradient spanned 50 m, from the wet middle to dry edge of the meadow, and soil volumetric water content was measured 0 to 12 cm deep. Fluxes of CO2, CH4, and N2O were measured using static chambers at 10 m intervals across the gradient. We found that the wet side of the gradient was not a CH4 or N2O source on either sampling date. Net CH4 emission from soil was rare and CH4 uptake was prevalent, particularly on the dry side of the gradient. Soil N 2O fluxes shifted from net uptake at the middle of the meadow to net emission at the edge, but only earlier in the growing season. Of the three GHGs, CO2 fluxes showed the most temporal variation but surprisingly varied little across the hydrological gradient. Other environmental factors-including plant species richness and soil carbon concentration-appeared more important than soil moisture in explaining CO2 fluxes. Therefore, the strength of near-surface hydrological control increased in the following order: CO2 < N2O < CH4. Our results suggest that non-CO2 greenhouse gases will need proper accounting during the snow-free season in order to more accurately predict the effects of future soil drying on GHG emissions in heterogeneous montane landscapes.
• Blankinship, J. C., & Hart, S. C. (2012). Consequences of manipulated snow cover on soil gaseous emission and N retention in the growing season: a meta-analysis. ECOSPHERE, 3(1).
• Brown, J. R., Blankinship, J. C., Niboyet, A., van Groenigen, K. J., Dijkstra, P., Le Roux, X., Leadley, P. W., & Hungate, B. A. (2012). Effects of multiple global change treatments on soil N 2O fluxes. Biogeochemistry, 109(Issue 1-3). doi:10.1007/s10533-011-9655-2
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  Global environmental changes are expected to alter ecosystem carbon and nitrogen cycling, but the interactive effects of multiple simultaneous environmental changes are poorly understood. Effects of these changes on the production of nitrous oxide (N 2O), an important greenhouse gas, could accelerate climate change. We assessed the responses of soil N 2O fluxes to elevated CO 2, heat, altered precipitation, and enhanced nitrogen deposition, as well as their interactions, in an annual grassland at the Jasper Ridge Global Change Experiment (CA, USA). Measurements were conducted after 6, 7 and 8 years of treatments. Elevated precipitation increased N 2O efflux, especially in combination with added nitrogen and heat. Path analysis supported the idea that increased denitrification due to increased soil water content and higher labile carbon availability best explained increased N 2O efflux, with a smaller, indirect contribution from nitrification. In our data and across the literature, single-factor responses tended to overestimate interactive responses, except when global change was combined with disturbance by fire, in which case interactive effects were large. Thus, for chronic global environmental changes, higher order interactions dampened responses of N 2O efflux to multiple global environmental changes, but interactions were strongly positive when global change was combined with disturbance. Testing whether these responses are general should be a high priority for future research. © 2011 Springer Science+Business Media B.V.
• Brown, J. R., Blankinship, J. C., Niboyet, A., van, G., Dijkstra, P., Le, R. X., Leadley, P. W., & Hungate, B. A. (2012). Effects of multiple global change treatments on soil N2O fluxes. BIOGEOCHEMISTRY, 109(1-3), 85-100.
• Duval, B. D., Blankinship, J. C., Dijkstra, P., & Hungate, B. A. (2012). CO2 effects on plant nutrient concentration depend on plant functional group and available nitrogen: a meta-analysis (Retracted article. See vol. 216, pg. 1675, 2015). PLANT ECOLOGY, 213(3), 505-521.
• Blankinship, J. C., Niklaus, P. A., & Hungate, B. A. (2011). A meta-analysis of responses of soil biota to global change. OECOLOGIA, 165(3), 553-565.
• Dijkstra, P., Blankinship, J. C., Selmants, P. C., Hart, S. C., Koch, G. W., Schwartz, E., & Hungate, B. A. (2011). Probing carbon flux patterns through soil microbial metabolic networks using parallel position-specific tracer labeling. SOIL BIOLOGY & BIOCHEMISTRY, 43(1), 126-132.
• Dijkstra, P., Blankinship, J. C., Selmants, P. C., Hart, S. C., Koch, G. W., Schwartz, E., & Hungate, B. A. (2011). Probing carbon flux patterns through soil microbial metabolic networks using parallel position-specific tracer labeling. Soil Biology and Biochemistry, 43(Issue 1). doi:10.1016/j.soilbio.2010.09.022
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  In order to study controls on metabolic processes in soils, we determined the dynamics of 13CO2 production from two position-specific 13C-labeled pyruvate isotopologues in the presence and absence of glucose, succinate, pine, and legume leaf litter, and under anaerobic conditions. We also compared 13CO2 production in soils along a semiarid substrate age gradient in Arizona. We observed that the C from the carboxyl group (C1) of pyruvate was lost as CO2 much faster than its other C atoms (C2,3). Addition of glucose, pine and legume leaf litter reduced the ratio between 13CO2 production from 1-13C pyruvate and 2,3-13C pyruvate (C1/C2,3 ratio), whereas anaerobic conditions increased this ratio. Young volcanic soils exhibited a lower C1/C2,3 ratio than older volcanic soils. We interpret a low C1/C2,3 ratio as an indication of increased Krebs cycle activity in response to carbon inputs, while the higher ratio implies a reduced Krebs cycle activity in response to anaerobic conditions. Succinate, a gluconeogenic substrate, reduced 13CO2 production from pyruvate to near zero, likely reflecting increased carbohydrate biosynthesis from Krebs cycle intermediates. The difference in 13CO2 production rate from pyruvate isotopologues disappeared 4-5 days after pyruvate addition, indicating that C positions were scrambled by ongoing soil microbial transformations. This work demonstrates that metabolic tracers such as pyruvate can be used to determine qualitative aspects of C flux patterns through metabolic pathways of soil microbial communities. Understanding the controls over metabolic processes in soil may improve our understanding of soil C cycling processes. © 2010 Elsevier Ltd.
• Niboyet, A., Brown, J. R., Dijkstra, P., Blankinship, J. C., Leadley, P. W., Le, R. X., Barthes, L., Barnard, R. L., Field, C. B., & Hungate, B. A. (2011). Global change could amplify fire effects on soil greenhouse gas emissions. PLOS ONE, 6(6).
• Niboyet, A., Brown, J. R., Dijkstra, P., Blankinship, J. C., Leadley, P. W., Roux, X., Barthes, L., Barnard, R. L., Field, C. B., & Hungate, B. A. (2011). Global change could amplify fire effects on soil greenhouse gas emissions. PLoS ONE, 6(Issue 6). doi:10.1371/journal.pone.0020105
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  Background: Little is known about the combined impacts of global environmental changes and ecological disturbances on ecosystem functioning, even though such combined impacts might play critical roles in shaping ecosystem processes that can in turn feed back to climate change, such as soil emissions of greenhouse gases. Methodology/Principal Findings: We took advantage of an accidental, low-severity wildfire that burned part of a long-term global change experiment to investigate the interactive effects of a fire disturbance and increases in CO2 concentration, precipitation and nitrogen supply on soil nitrous oxide (N2O) emissions in a grassland ecosystem. We examined the responses of soil N2O emissions, as well as the responses of the two main microbial processes contributing to soil N2O production - nitrification and denitrification - and of their main drivers. We show that the fire disturbance greatly increased soil N2O emissions over a three-year period, and that elevated CO2 and enhanced nitrogen supply amplified fire effects on soil N2O emissions: emissions increased by a factor of two with fire alone and by a factor of six under the combined influence of fire, elevated CO2 and nitrogen. We also provide evidence that this response was caused by increased microbial denitrification, resulting from increased soil moisture and soil carbon and nitrogen availability in the burned and fertilized plots. Conclusions/Significance: Our results indicate that the combined effects of fire and global environmental changes can exceed their effects in isolation, thereby creating unexpected feedbacks to soil greenhouse gas emissions. These findings highlight the need to further explore the impacts of ecological disturbances on ecosystem functioning in the context of global change if we wish to be able to model future soil greenhouse gas emissions with greater confidence. © 2011 Niboyet et al.
• Niboyet, A., Le Roux, X., Dijkstra, P., Hungate, B. A., Barthes, L., Blankinship, J. C., Brown, J. R., Field, C. B., & Leadley, P. W. (2011). Testing interactive effects of global environmental changes on soil nitrogen cycling. Ecosphere, 2(Issue 5). doi:10.1890/es10-00148.1
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  Responses of soil nitrogen (N) cycling to simultaneous and potentially interacting global environmental changes are uncertain. Here, we investigated the combined effects of elevated CO2, warming, increased precipitation and enhanced N supply on soil N cycling in an annual grassland ecosystem as part of the Jasper Ridge Global Change Experiment (CA, USA). This field experiment included four treatments-CO2, temperature, precipitation, nitrogen-with two levels per treatment (ambient and elevated), and all their factorial combinations replicated six times. We collected soil samples after 7 and 8 years of treatments, and measured gross rates of N mineralization, N immobilization and nitrification, along with potential rates of ammonia oxidation, nitrite oxidation and denitrification. We also determined the main drivers of these microbial activities (soil ammonium and nitrate concentrations, soil moisture, soil temperature, soil pH, and soil CO 2 efflux, as an indicator of soil heterotrophic activity). We found that gross N mineralization responded to the interactive effects of the CO 2, precipitation and N treatments: N addition increased gross N mineralization when CO2 and precipitation were either both at ambient or both at elevated levels. However, we found limited evidence for interactions among elevated CO2, warming, increased precipitation, and enhanced N supply on the other N cycling processes examined: statistically significant interactions, when found, tended not to persist across multiple dates. Soil N cycling responded mainly to single-factor effects: long-term N addition increased gross N immobilization, potential ammonia oxidation and potential denitrification, while increased precipitation depressed potential nitrite oxidation and increased potential ammonia oxidation and potential denitrification. In contrast, elevated CO2 and modest warming did not significantly affect any of these microbial N transformations. These findings suggest that global change effects on soil N cycling are primarily additive, and therefore generally predictable from single factor studies. Copyright: © 2011 Niboyet et al.
• Niboyet, A., Le Roux, X., Dijkstra, P., Hungate, B., Barthes, L., Blankinship, J., Brown, J., Field, C., & Leadley, P. (2011). Testing interactive effects of global environmental changes on soil nitrogen cycling. ECOSPHERE, 2, art56. doi:10.1890/ES10-00148.1
• Blankinship, J. C., Brown, J. R., Dijkstra, P., & Hungate, B. A. (2010). Effects of interactive global changes on methane uptake in an annual grassland. JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES, 115.
• Blankinship, J. C., Brown, J. R., Dijkstra, P., Allwright, M. C., & Hungate, B. A. (2010). Response of Terrestrial CH4 Uptake to Interactive Changes in Precipitation and Temperature Along a Climatic Gradient. Ecosystems, 13(Issue 8). doi:10.1007/s10021-010-9391-9
  More info

  We determined the response of terrestrial methane (CH4) uptake to 4 years of full-factorial manipulations of precipitation and temperature in four ecosystems along a 50 km warm and dry to cold and wet climatic gradient (desert grassland, pinyon-juniper woodland, ponderosa pine forest, and mixed conifer forest). Our goals were to determine whether ecosystem-specific, intraannual, and interactive responses to altered precipitation and warming are quantitatively important. Passive collectors and interceptors increased (+50% per event) and reduced (-30% per event) the quantity of precipitation delivered to experimental plant-soil mesocosms, and downward transfer along the elevation gradient warmed mesocosms by 1.8°C on average. Methane uptake in the colder and wetter ecosystems along the gradient decreased with increasing precipitation, especially during the wet season. The warmer and drier ecosystems, however, responded more strongly to warming, exhibiting less CH4 uptake with increasing temperature. We found no interaction between altered precipitation and warming in any ecosystem. Soil CH4 consumption in the laboratory was a strong predictor of ecosystem differences in field CH4 consumption, but was a poor predictor of the effects of climatic change observed in the field. Based on our results, future climate scenarios that are wet and warm will cause the largest reduction in terrestrial CH4 uptake across ecosystem types. © 2010 Springer Science+Business Media, LLC.
• Blankinship, J. C., Brown, J. R., Dijkstra, P., Allwright, M. C., & Hungate, B. A. (2010). Response of terrestrial CH4 uptake to interactive changes in precipitation and temperature along a climatic gradient. ECOSYSTEMS, 13(8), 1157-1170.
• Brown, J. R., Blankinship, J. C., Dijkstra, P., & Hungate, B. A. (2010). Effects of interactive global changes on methane uptake in an annual grassland: CH₄FLUXES AND GLOBAL CHANGE. Journal of Geophysical Research: Biogeosciences, 115(G2), n/a-n/a. doi:10.1029/2009jg001097
• Blankinship, J. C., Riveros-Iregui, D. A., & Desai, A. R. (2008). NCAR Advanced Study Program students "method hop" their way to regional biogeochemistry. BULLETIN OF THE AMERICAN METEOROLOGICAL SOCIETY, 89(10), 1571-1573.
• Barnard, R., Blankinship, J., Le Roux, X., Hungate, B., Cleland, E., Barthes, L., & Paul, L. (2006). Several components of global change alter nitrifying and denitrifying activities in an annual grassland. FUNCTIONAL ECOLOGY, 20, 557-564.
• Barnard, R., Roux, X. L., Hungate, B. A., Cleland, E. E., Blankinship, J. C., Barthes, L., & Leadley, P. W. (2006). Several components of global change alter nitrifying and denitrifying activities in an annual grassland. Functional Ecology, 20(Issue 4). doi:10.1111/j.1365-2435.2006.01146.x
  More info

  1. The effects of global change on below-ground processes of the nitrogen (N) cycle have repercussions for plant communities, productivity and trace gas effluxes. However, the interacting effects of different components of global change on nitrification or denitrification have rarely been studied in situ. 2. We measured responses of nitrifying enzyme activity (NEA) and denitrifying enzyme activity (DEA) to over 4 years of exposure to several components of global change and their interaction (increased atmospheric CO2 concentration, temperature, precipitation and N addition) at peak biomass period in an annual grassland ecosystem. In order to provide insight into the mechanisms controlling the response of NEA and DEA to global change, we examined the relationships between these activities and soil moisture, microbial biomass C and N, and soil extractable N. 3. Across all treatment combinations, NEA was decreased by elevated CO2 and increased by N addition. While elevated CO2 had no effect on NEA when not combined with other treatments, it suppressed the positive effect of N addition on NEA in all the treatments that included N addition. We found a significant CO2-N interaction for DEA, with a positive effect of elevated CO2 on DEA only in the treatments that included N addition, suggesting that N limitation of denitrifiers may have occurred in our system. Soil water content, extractable N concentrations and their interaction explained 74% of the variation in DEA. 4. Our results show that the potentially large and interacting effects of different components of global change should be considered in predicting below-ground N responses of Mediterranean grasslands to future climate changes. © 2006 The Authors.

Presentations

• Blankinship, J. (2025).

  Does soil health influence food quality?

  . Southwest Agricultural Summit. Yuma, AZ.
• Blankinship, J. (2025).

  Introducing the International Center for Arid Soil Health (I-CASH)

  . Ag 100 Council Meeting. Gilbert, AZ.
• Blankinship, J. (2025).

  Linking resilience to agircultural soil health in arid climates

  . Indigenous Resilience Center Retreat.
• Blankinship, J. (2025).

  Overview of Desert Agriculture Soil Health Initiative (DASHI)

  . Foundation for Food and Agriculture Research Webinar.
• Blankinship, J. (2025).

  Resilience depends on healthy soils

  . Arizona Institute for Resilience: Perspectives on Resilience Conference.
• Blankinship, J. (2025).

  Resilience through soil health in arid agricultural regions

  . Foundation for Food and Agriculture Research Convening on Cultivating Resilient Arid-Land Agricultural Systems and Communities. Yuma, AZ.
• Blankinship, J. (2025).

  Soil health regeneration in the dry half of the world

  . International Center for Biosaline Agriculture. Virtual with attendees in United Arab Emirates.
• Blankinship, J. (2025).

  Soil health regeneration in the dry half of the world

  . Regenerative Agriculture Summit. Anaheim, CA.
• Blankinship, J. (2025).

  Sustaining agricultural soil health in a drying world

  . CANVAS Annual Meeting. Salt Lake City, UT.
• Blankinship, J. (2025).

  The Yuma Soil Health Monitoring Program

  . YCEDA Advisory Council Meeting.
• Blankinship, J. (2025).

  What are the links between soil health, crop nutrient density, and human health?

  . Linking Soil, Crop, and Human Nutrition (organized by J. Blankinship). Virtual.
• Blankinship, J. (2025).

  What's at stake if we don't sustain soil health in arid agricultural regions?

  . Foundation for Food and Agriculture Research Webinar.
• Blankinship, J., Martin, E., Chorover, J., Slinski, S., & Rock, C. (2025).

  University of Arizona Functions Supporting Agriculture in Arizona

  . Arizona Board of Regents: Building a roadmap for a resilient future in agriculture production in an arid environment.
• Ball, K., & Blankinship, J. (2021). Hung out to dry: How the reliance on metrics developed for soil health assessment in temperate systems may leas to erroneous management advice in arid systems. National Cooperative Soil Survey National Conference.
• Blankinship, J. (2021). Assessing and enhancing soil health to mitigate dust, rehabilitate rangelands, and sustain croplands. ENVS Colloquium.
• Blankinship, J. (2021). Benefits and limitations of Biological Soil Amendments of Animal Origin (BSAAO) for desert soil health. FDA Biological Soil Amendments of Animal Origin (BSAAO) Workshop. Estralla Community College.
• Blankinship, J. (2021). Linking soil health to dust prediction and mitigation: Project updates from University of Arizona research team. Arizona Annual Dust WorkshopNational Weather Service.
• Blankinship, J. (2021). Roles and opportunties of organic matter and microorganisms for arid soil health. Southwest Agricultural Summit. Yuma.
• Blankinship, J. (2021). Soil health research in desert cropping systems. Yuma Center for Excellence in Desert Agriculture (YCEDA) Donors Meeting.
• Blankinship, J., Ball, K., Muscarella, C., & Rathke, S. (2021). The dry side of soil health: Developing a new framework for measuring and enhancing soil health in arid agroecosystems. NRCS Dynamic Soil Properties for Soil Health (DSP4SH) Annual Meeting.
• Blankinship, J., Blankinship, J., Rathke, S., Rathke, S., Babst-Kostecka, A., Babst-Kostecka, A., Gornish, E., Gornish, E., Barberan, A., Barberan, A., Field, J., Field, J., Saez, A. E., Saez, A. E., Rasmussen, C., Rasmussen, C., Tfaily, M., & Tfaily, M. (2021). Mitigating dust pollution for climate-resilient development in arid regions. Symposium on Resilience Research for Global Development ChallengesArizona Institutes for Environment.
• Blankinship, J., Rathke, S., Rasmussen, C., Field, J. P., & Saez, A. E. (2021). Deadly dust on Arizona highways: Developing an improved dust risk index based on soil stabilization mechanisms and Ecological Site Descriptions. National Cooperative Soil Survey National Conference.
• Muscarella, C., Ball, K., & Blankinship, J. (2021). Are extracellular enzyme activities a useful indicator of nutrient availability in semi-arid soils?. American Geophysical Union Fall Meeting.
• Blankinship, J. (2020, February). Evaluating and nurturing soil health in desert agriculture. 2020 Southwest Ag Summit. Yuma, AZ.
• Blankinship, J. (2020, January). Evaluating landscape-scale soil health interventions and their ecosystem services. Altar Valley Soil Health Workshop.
• Blankinship, J. (2020, July). Soil organic matter as a holistic indicator of desert soil health. Desert Southwest Soil Health Webinar.
• Blankinship, J. (2020, June). Foundation for Food & Agriculture Research (FFAR) Project Proposal to Yuma Lettuce Industry. Yuma Center for Excellence in Desert Agriculture.
• Blankinship, J. (2020, March). Adding organic materials to accelerate soil stabilization and dust mitigation. 2020 Arizona Dust Workshop. Coolidge, AZ: NOAA, ADEQ, and ADOT.
• Blankinship, J. (2020, September). Assessing and enhancing soil health to mitigate dust, rehabilitate rangelands, and sustain croplands. Northern Arizona University Foresty Departmental Seminar.
• Blankinship, J. (2019, April). Launchging the Arizona Carbon Project: Soil carbon accounting and sequestration in the Sonoran Desert. CALS Deans Research Advisory Committee (DRAC) Meeting. University of Arizona Main Campus.
• Blankinship, J. (2019, April). Soil aggregates in the desert: Where did they go and how do we get them back?. New Mexico Institute of Mining and Technology. Socorro, NM: Biology Departmental Seminar.
• Blankinship, J. (2019, December). Predicting and mitigating dust emissions from barren lands. Arizona State Dust Group Fall Meeting. Phoenix, AZ: Arizona Department of Environmental Quality.
• Blankinship, J. (2019, January). Soils! The world beneath your feet. Envirothon. University of Arizona Main Campus.
• Blankinship, J. (2019, March). Testing carbon- and microbial-based strategies for soil stabilization and dust mitigation in barren lands of the Sonoran Desert. 2019 Arizona Dust Storm Workshop. Central Arizona College: National Weather Service.
• Blankinship, J. (2019, November). Advancing the science of soil health in dryland restoration. Society for Ecological Restoration Southwest Chapter Annual Meeting. University of Arizona Main Campus.
• Blankinship, J., Perno, S., Leger, A., & Rathke, S. (2019, January). Manifesting drought in the Desert Southwest: Soil biogeochemical signals and opportunities for mitigation. Soil Science Society of America Annual Meeting. San Diego, CA.
• Leger, A., Rathke, S., & Blankinship, J. (2019, January). Rangeland compost application. Stakeholder outreach meeting with Emily Rockey from Tank's Green Stuff. University of Arizona Main Campus.
• Leger, A., Rathke, S., & Blankinship, J. (2019, March). Soil health and soil organic matter in southern Arizona. UA Earth Week Plneary Session Lightning Talks. University of Arizona Main Campus.
• Leger, A., Rathke, S., & Blankinship, J. (2019, November). Mulch and compost for semi-arid grassland restoration: Influences on soil health and vegetation. Society for Ecological Restoration Southwest Chapter Annual Meeting. University of Arizona Main Campus.
• Trumbore, S., Hoyt, A., Lawrence, C., Monroe, G., Heckman, K., Sierra, C., Blankinship, J., Beem-Miller, J., Stoner, S., & McNichol, G. (2019, April). ISRaD: the International Soil Radiocarbon Database. European Geophysical Union Annual Meeting. Vienna, Austria.
• Blankinship, J. (2018, August). Improving soil health in low-productivity rangelands. Discussion with Arizona State Land Department. Phoenix, AZ.
• Blankinship, J. (2018, August). Increasing soil value: quantifying organic matter and its benefits for soil health and agricultural sustainability in Arizona. Arizona Pecan Growers Association Annual Meeting. Desert Diamond Hotel, Tucson, AZ.
• Blankinship, J. (2018, August). Potential for mitigating wind erosion in the Sonoran Desert using organic amendments and microbes to build soil aggregates. Soil and Water Conservation Society Annual Conference. Albuquerque, NM.
• Blankinship, J. (2018, July). Nurturing soil health in degraded arid rangelands. Altar Valley Conservation Alliance Science Advisory Board Meeting. Tucson.
• Blankinship, J. (2018, May). Micro-niche formation in arid systems. Biosphere 2 Workshop: Eco-Engineering of Life in Arid Landscapes. Biosphere 2: University of Arizona RDI.
• Blankinship, J., Leger, A., Perno, S., & Rathke, S. (2019, January). Manifesting drought in the Desert Southwest: soil biogeochemical signals and opportunities for mitigation. Soiil Science Society of America Annual Meeting. San Diego, CA.
• Hart, S., & Blankinship, J. (2018, June). Consequences of warming and altered snowmelt timing on greenhouse gas fluxes and soil N cycling in the Sierra Nevada rain-snow transition zone. North American Forest Soils Conference International Symposium on Forest Soils. Quebec City, Quebec, Canada.
• Homyak, P., Blankinship, J., Slessarev, E., Schaeffer, S., Manzoni, S., & Schimel, J. (2018, August). Mechanisms governing soluble soil carbon in drying soils: exoenzymes vs. physics. Ecological Society of America Annual Meeting. New Orleans, LA.
• Lawrence, C., Beem-Miller, J., Blankinship, J., Crow, S., Hatte, C., Heckman, K., He, Y., Hoyt, A., Keiluweit, M., Monroe, G., Sierra, C., Stoner, S., Treat, C., & Trumbore, S. (2018, December). The International Soil Radiocarbon Database (ISRaD): a new resource for the synthesis of soil radiocarbon data across scales. American Geophysical Union Fall Meeting. Washington, D.C..
• Blankinship, J. (2017, May). What lies below? Improving understanding and quantification of soil carbon storage. United States Geological Survey Powell Center Seminar Series. Fort Collins, CO.
• Blankinship, J. (2017, October). Building soil aggregates to improve soil health and accelerate restoration of degraded arid ecosystems. Altar Valley Conservation Alliance Board of Directors Meeting.
• Blankinship, J., & Lawrence, C. (2017, June). Nurturing a mechanistic view of soil health. Ecology of Soil Health Summit.
• Blankinship, J., Morse, H., Marchus, K., & Schimel, J. (2017, June). Using extracellular polymeric substances (EPS) from bacteria to make soils more drought-adapted. Soil Ecology Society Biennial Meeting.

Poster Presentations

• Ball, K., Crow, S., Brien, C., Berhe, A., Rathke, S., & Blankinship, J. (2021). Inorganic carbon mediates tillage legacy effects on soil organic carbon stocks in arid agricultural soils. American Geophysical Union Fall Meeting. New Orleans, LA.
• Hart, S., & Blankinship, J. (2021). Transferring forest soil to a lower altitude enhances greenhouse gas fluxes and nitrogen transformations in a Mediterranean-type climate. American Geophysical Union Fall Meeting.
• Hoglund, S., Rathke, S., & Blankinship, J. (2019, July). Increasing soil carbon for desert agriculture. United States Biochar Initiative (USBI) Annual Meeting. Fort Collins, CO.
• Hoglund, S., Rathke, S., & Blankinship, J. (2019, March). Increasing soil carbon for future water solutions and desert agricultural sustainability. ALVSCE Poster Forum. University of Arizona Main Campus.
• Hoglund, S., Rathke, S., & Blankinship, J. (2019, March). Increasing soil carbon for future water solutions and desert agricultural sustainability. SWESx Poster Fourm. University of Arizona Main Campus.
• Leger, A., Rathke, S., & Blankinship, J. (2019, March). Soil amendments and soil organic matter to improve soil health. SWESx Poster Session. University of Arizona Main Campus.
• Beem-Miller, J., Lawrence, C., Blankinship, J., Hoyt, A., Stoner, S., Sierra, C., Monroe, G., McNicol, G., He, Y., Hatte, C., Treat, C., Crow, S., Heckman, K., Keiluweit, M., & Trumbore, S. (2018, June). From fractions to fluxes: the International Soil Radiocarbon Database. International Radiocarbon Annual Conference. Trondheim, Norway.
• Jones, J., & Blankinship, J. (2018, April). Biochar as a potential means for climate change mitigation and adaptation in dryland soils. SWESx. Tucson, AZ: UA Earth Week.
• Leger, A., & Blankinship, J. (2018, April). Challenges and opportunities for carbon sequestration in dryland ecosystems. SWESx. Tucson, AZ: UA Earth Week.
• Perno, S., & Blankinship, J. (2018, April). The effects of wet-dry cycles on greenhouse gas emissions from southern Arizona compost sources. SWESx. Tucson, AZ: UA Earth Week.
• Gebhardt, M., Espinosa, N., Blankinship, J., & Gallery, R. E. (2017, Dec). B14B-02: A meta-analysis of soil exoenzyme responses to simulated climate change. American Geophysical Union (AGU). New Orleans, LA: AGU.
• Perno, S., & Blankinship, J. (2018, January). The effects of wet-dry cycles on greenhouse gas emissions from southern Arizona compost sources. Undergraduate Biology Research Program Annual Conference.

Others

• Blankinship, J., Hungate, B., & Schwartz, E. (2015, October). Soil methanotrophic communities after simulated climate change along an elevation gradient. KNOWLEDGE NETWORK FOR BIOCOMPLEXITY.