Research Interests
Education
2002-2007: Ph.D. in Natural Resources, University of Idaho
Dissertation title: Effects of forest fires on soil nitrogen dynamics in coniferous forests of central Idaho, USA
Advisor: Dr. Kathleen L. Kavanagh
1999-2002: M.S. in Forest Resources, University of Idaho
Thesis title: Contribution of salmon-derived nitrogen to riparian conifer forests in central Idaho, USA
Advisor: Dr. Kathleen L. Kavanagh
1991-1995: B.S. in Forest Science, Tokyo University of Agriculture and Technology
Senior thesis title: Nutrient characteristics of stream water discharged from forested watersheds
Advisor: Dr. Takayoshi Koike
Academic Appointment
2015 to now: Post-doctoral fellow, Department of Biology, Algoma University.
Advisor: Dr. Pedro Antunes
2011 to 2015: Post-doctoral associate, Natural Resource Ecology Laboratory and Department of Biology, Colorado State University.
Advisors: Drs. Matthew D. Wallenstein, Joseph C. von Fischer, and John C. Moore
Research Topics: 1) Assessment of soil microbial response to increased nutrient availability in an Arctic tundra ecosystem, 2) Connecting microbial structures and ecosystem functions; how do methanotroph community structures affect methane consumption dynamics in grassland soils across the US Great Plains?
2007-2009: Post-doctoral fellow, School of Biological Sciences, Washington State University.
Advisor: Dr. R. Dave Evans
Research Topic: Quantification of soil organic carbon and nitrogen balance in a Mojave Desert ecosystem after 10 years of exposure to elevated CO2 at the Nevada Free Air CO2 Enrichment (FACE) Facility
Publications
Grants received
Teaching
Instructor
Guest Lectures
Teaching Assistant
Invited presentations
Contributed presentations
Awards
2002: Outstanding Graduate Student of Forest Resources, College of Natural Resources, University of Idaho
2001: Travel Award for Salmon Nutrient Conference in Eugene, Oregon, from American Fisheries Society. $450
1999: International Student Tuition Waiver, from International Program Office. $1500
Professional Societies
American Geophysical Union
Ecological Society of America
Soil Ecology Society
Manuscript Reviewer for Scientific Journals
Global Change Biology (4), Biogeochemistry (4), Oecologia (3), Canadian Journal of Microbiology (2), Ecosystems (1), Forest Ecology and Management (1), FEMS Microbiology Ecology (1), Science of Total Environment (1), PLoS ONE (2), International Journal of Wildland Fire (1), Soil Biology and Biochemistry (5), Biogeosciences (1), Ecological Indicators (1), World Journal of Microbiology and Biotechnology (1), Western North American Naturalist (1), Plant and Soil (1)
My Publon profile:
https://publons.com/author/655781/akihiro-koyama#profile
Proposal Reviewer for Scientific Organizations
2014: Long Term Research in Environmental Biology, National Science Foundation, USA (Mail-in)
2015: Environmental System Science, Arctic Panel, Department of Energy, USA
2015: National Science Centre, Poland (Mail-in)
Extra-Curricular Activities
2013: Organizing committee for Front Range Isotope Day (FRIDay), Natural Resource Ecology Laboratory, Colorado State University
2012-2013: Selection committee of Francis Clark Scholarship and James E. Ellis Memorial Scholarship, Natural Resource Ecology Laboratory, Colorado State University
2012: Post-doctoral fellow search committee for Department of Biology, Colorado State University
2002-2003: Representative of graduate students, Department of Forest Resources for College of Natural Resources Redesign Committee, University of Idaho
2002-2003: Representative of graduate students, Department of Forest Resources for University of Idaho Graduate Student Association
2000-2001: Facilitated and participated in International Student Orientation, University of Idaho
1999-2000: President of Japanese Student Association, University of Idaho
Aerial view of experimental plots near Toolik Lake, Alaska.
The Arctic i
- Structure and function of soil and root microbes, including fungi and bacteria
- Carbon and nutrient dynamics in the plant-microbe-soil complex
- Microbially-mediated biogeochemical processes in response to global change factors including elevated atmospheric CO2, warming, nitrogen deposition and land use change
- Use of stable isotopes to elucidate biogeochemical processes
Education
2002-2007: Ph.D. in Natural Resources, University of Idaho
Dissertation title: Effects of forest fires on soil nitrogen dynamics in coniferous forests of central Idaho, USA
Advisor: Dr. Kathleen L. Kavanagh
1999-2002: M.S. in Forest Resources, University of Idaho
Thesis title: Contribution of salmon-derived nitrogen to riparian conifer forests in central Idaho, USA
Advisor: Dr. Kathleen L. Kavanagh
1991-1995: B.S. in Forest Science, Tokyo University of Agriculture and Technology
Senior thesis title: Nutrient characteristics of stream water discharged from forested watersheds
Advisor: Dr. Takayoshi Koike
Academic Appointment
2015 to now: Post-doctoral fellow, Department of Biology, Algoma University.
Advisor: Dr. Pedro Antunes
2011 to 2015: Post-doctoral associate, Natural Resource Ecology Laboratory and Department of Biology, Colorado State University.
Advisors: Drs. Matthew D. Wallenstein, Joseph C. von Fischer, and John C. Moore
Research Topics: 1) Assessment of soil microbial response to increased nutrient availability in an Arctic tundra ecosystem, 2) Connecting microbial structures and ecosystem functions; how do methanotroph community structures affect methane consumption dynamics in grassland soils across the US Great Plains?
2007-2009: Post-doctoral fellow, School of Biological Sciences, Washington State University.
Advisor: Dr. R. Dave Evans
Research Topic: Quantification of soil organic carbon and nitrogen balance in a Mojave Desert ecosystem after 10 years of exposure to elevated CO2 at the Nevada Free Air CO2 Enrichment (FACE) Facility
Publications
- Koyama, A., B. Harlow, C.R. Kuske, J. Belnap, R.D. Evans. (2018) Mechanisms of soil organic carbon and nitrogen accumulation in a Mojave Desert ecosystem after 10 years exposure to elevated carbon dioxide. Soil Biology and Biochemistry.
- Koyama, A., J.M. Steinweg, M.L. Haddix, J.S. Dukes, M.D. Wallenstein. (2017) Soil bacterial community structured by plants in response to altered precipitation and temperature regimes in an old field grassland. FEMS Microbiology Ecology
- Koyama, A., O. Pietrangelo, L. Sanderson, P.M. Antunes (2017) An empirical investigation of the possibility of adaptability of arbuscular mycorrhizal fungi to new hosts. Mycorrhiza. DOI: 10.1007/s00572-017-0776-x
- Wang, X., E. Agathokleous, L. Qu, S. Fujita, M. Watanabe, Y. Tamai, Q. Mao, A. Koyama, T. Koike. (2017) Effects of simulated nitrogen deposition on ectomycorrhizae community structure in hybrid larch and its parents grown in volcanic ash soil: the role of phosphorous. Science of the Total Environment. DOI: 10.1016/j.scitotenv.2017.08.283
- Carrillo, Y., C. Bell, A. Koyama, A. Canarini, C.M. Boot, M. Wallenstein, E. Pandel. (2017) Plant traits, stoichiometry and microbes as drivers of decomposition in the rhizosphere in a temperate grassland. Journal of Ecology. DOI: 10.1111/1365-2745.12772
- Thompson*, M.T.C., A. Koyama, K.L. Kavanagh. (2016). Wildfire effects on physiological properties in conifers of central Idaho forests, USA. Trees – Structure and Function. DOI: 10.1007/s00468-016-1489-z
- Alster, C. J., A. Koyama, N. G. Johnson, M. D. Wallenstein, J. C. von Fischer (2016). Temperature sensitivity of soil microbial communities: an application of macromolecular rate theory to microbial respiration. Journal of Geophysical Research: Biogeosciences:2016JG003343. DOI: 10.1002/2016JG003343
- Judd, C.R., A. Koyama, M.P. Simmons, P. Brewer, N. Fierer, J.C. von Fischer (2016) Co-variation in methanotroph community composition and activity in three temperate grassland soils. Soil Biology and Biochemistry.
- Stephan, K., K. L. Kavanagh, A. Koyama. (2015) Influence of fire on watershed nitrogen cycling using 15N natural abundance in terrestrial and aquatic ecosystem components. PloS ONE 10:e0119560.
- Wang, X., L. Qu, Q. Mao, M. Watanabe, Y. Hoshika, A. Koyama, K. Kawaguchi, Y. Tamai, T. Koike. (2015) Ectomycorrhizal colonization and growth of the hybrid larch F1 under elevated CO2 and O3. Environmental Pollution. 197:116-126.
- Koyama, A., Wallenstein, M.D., Simpson, R.T., and Moore, J.C. (2014). Soil bacterial community composition altered by increased nutrient availability in Arctic tundra soils. Frontiers in Microbiology 5. DOI: 10.3389/fmicb.2014.00516
- Evan, R.D., A. Koyama, D. Sonderegger, T.N. Charlet, B. Newingham, L.F. Fenstermaker, B. Harlow, K. Ogle, S.D. Smith, R.S. Nowak. (2014) Greater ecosystem carbon in the Mojave Desert after ten years exposure to elevated CO2. Nature Climate Change. DOI:10.1038/NCLIMATE2184.
- Moore, J.C., R.B. Boone, A. Koyama, K. Holfelder. (2014) Enzymatic and Detrital Influences on the Structure, Function, and Dynamics of Spatially-Explicit Model Ecosystems. Biogeochemistry: 1-23. DOI: 10.1007/s10533-013-9932-3
- Koyama, A., M.D. Wallenstein, R.T. Simpson and J.C. Moore. (2013). Carbon-degrading enzyme activities stimulated by increased nutrient availability in Arctic tundra soils. PLoS ONE 8: e77212. DOI: 10.1371/journal.pone.0077212.
- Stephan, K., K.L. Kavanagh, A. Koyama. (2012). Effects of spring prescribed burning and wildfires on watershed nitrogen dynamics of central Idaho headwater areas. Forest Ecology and Management. 263: 240-252. DOI: DOI:10.1016/j.foreco.2011.09.013.
- Koyama, A., K. Stephan, K. L. Kavanagh. (2011). Fire effects on gross inorganic N transformation in riparian soils in coniferous forests of central Idaho, USA: Wildfires vs. prescribed fires. International Journal of Wildland Fire. 21(1) 69-78.
- Koyama, A., K.L. Kavanagh, K. Stephan. (2010). Wildfire effects on gross nitrogen transformation rates in mineral soils in coniferous forests of central Idaho, USA. Ecosystems 13(7): 1112-1126. DOI: 10.1007/s10021-010-9377-7.
- Koyama A., K.L. Kavanagh, A. Robinson. (2005). Marine nitrogen in central Idaho riparian forests: evidence from stable isotopes. Canadian Journal of Fisheries and Aquatic Sciences 62: 518-526.
Grants received
- Kavanagh, K.L., G.W. Minshall, N. Bosworth, K. Stephan, A. Koyama. 2005. The effect of wildfire on nitrogen dynamics within headwater ecosystems. Joint Fire Science Program. $77,200. Project number 05-2-1-41
- Kavanagh, K.L., G.W. Minshall, J. Erickson, K. Stephan, A. Koyama. 2004. The effect of spring prescribed fires on nitrogen dynamics within riparian and stream ecosystems. Joint Fire Science Program. $74,500. Project number 04-2-1-97
Teaching
Instructor
- Colorado State University, Summer Soil Institute, Natural Resource Ecology Laboratory (Co-instructor for soil microbial molecular techniques in the lab and CH4 flux measurement in the field)
- Colorado State University, On Changing Arctic (ECOL592), Department of Biology (Co-instructor, 1 credit, Fall 2012)
Guest Lectures
- Colorado State University, Fire Effects and Adaptations (F324), Department of Forest and Rangeland Stewardship (March 2014) "Forest fire effects on nitrogen dynamics"
- Colorado State University, Ecosystem Ecology (RS351, ESS311), Department of Ecosystem Science and Sustainability (September 2013) "Soil organic matter and decomposition"
- Colorado State University, Ecosystem Ecology (ECOL610), Department of Biology (October 2012) "On pool sizes and flux rates"
- Colorado State University, Biogeochemistry (NR660), Department of Ecosystem Science and Sustainability (February 2012) "On methods to measure soil nitrogen dynamics"
- Colorado State University, Terrestrial Ecosystems Isotope Ecology (SOCR670), Soil and Crop Sciences (March 2011, 2013, 2014) "Nitrogen isotope pool dilution method to measure gross nitrogen transformation rates"
- Washington State University, Graduate Biogeochemistry Seminar, School of Earth and Environmental Sciences (March 2008) “Fire effects on nitrogen dynamics in coniferous forests”
- Washington State University , Ecosystem Ecology and Global Change (BIO469/569), School of Biological Sciences (November 2007) “Effects of elevated CO2 on terrestrial ecosystem processes”
- University of Idaho, Fish and Wildlife Department, Fish Ecology (October 2005) “Marine-derived nitrogen in riparian forests of inland Northwest”
Teaching Assistant
- University of Idaho, Forest Measurements and Inventory, Forest Resources (3 credits, Spring 2007), for undergraduate course (36 students)
- University of Idaho, Principles of Ecosystem Management, Forest Resources (2 credits, Spring 2000, 2001), for undergraduate course (~ 50 students)
Invited presentations
- Koyama, A. 2016. Two tales of nitrogen in Western inland forests. Great Lakes Forestry Centre, Sault Ste. Marie, Ontario, Canada.
- Koyama, A., B. Harlow, C.R. Kuske, J. Belnap, R.D. Evans. 2015 Mechanisms of soil organic carbon and nitrogen accumulation in a Mojave Desert ecosystem after 10 years exposure to elevated carbon dioxide. Biology Department Seminar, Algoma University, Sault Ste. Marie, Ontario, Canada.
Koyama, A., K. Stephan, K.L. Kavanagh. 2012. Fire effects on Nitrogen dynamics in soils and streams in headwater coniferous forests of central Idaho, USA. Department of Forest Science Seminar, Spring 2012, Hokkaido University, Japan. - Koyama, A., R.D. Evans. 2012. Soil organic carbon and total nitrogen dynamics in a Mojave Desert ecosystem exposed to elevated CO2. Department of Forest Science Seminar, Spring 2012, Hokkaido University, Japan.
- Koyama, A., R.D. Evans. 2011. Soil organic carbon and nitrogen balance in a desert ecosystem after 10 years exposure to elevated carbon dioxide. Natural Resource Ecology Laboratory Seminar Spring 2011, Colorado State University, Fort Collins, CO, USA.
- Stephan, K., A. Koyama, K.L. Kavanagh. 2007. Soil nutrient status following prescribed burns and wildfire. Intermountain Forest Tree Nutrition Cooperative Annual Meeting, Moscow ID, USA
- Stephan, K., A. Koyama, K.L. Kavanagh. 2006. Comparison of wildfire and prescribed burn effects on nitrogen dynamics in central Idaho headwater ecosystems. Spring Fire Management Meeting, Boise National Forest, Eagle, ID, USA.
- Kavanagh, K.L., A. Koyama, A. Robinson. 2001. Nutrients on the salmon superhighway: Is it a two-way street? Third North American Forest Ecology Workshop. Duluth, MN.
- Kavanagh, K.L., A. Koyama, A. Robinson 2001. Movement of salmonid-derived nitrogen into riparian conifer forests of Central Idaho. Restoring Nutrients to Salmonid Ecosystems. American Fisheries Society. Eugene, OR.
Contributed presentations
- Koyama, A., T. Dias, A. Dukes, P.M. Antunes. 2017. Soil microbial feedback in agricultural crop rotation. Soil Ecology Society Meeting, Fort Collins, CO, USA.
- Tfaily, M.M., N.J. Hess, A. Koyama, R.D. Evans. 2016. Organic matter composition and substrate diversity under elevated CO2 in the Mojave Desert. American Geophysical Union Fall Meeting, San Francisco, CA, USA.
- Koyama, A., N.G. Johnson, P. Brewer, C.T. Webb, J.C. von Fischer. 2015. Field measures show methanotroph sensitivity to soil moisture follows precipitation regime of the grassland sites across the US Great Plains. American Geophysical Union Fall Meeting, San Francisco, CA, USA.
- von Fischer, J.C., A. Koyama, N. G. Johnson, C.T. Webb. 2015. A hierarchical examination of methane uptake: Field patterns, lab physiology, community composition and biogeography. American Geophysical Union Fall Meeting, San Francisco, CA, USA.
- Alster, C., A. Koyama, N. G. Johnson, J.C. von Fischer. A Comparison of Arrhenius and Macromolecular Rate Theory for predicting temperature responses of soil CO2 production. American Geophysical Union Fall Meeting, San Francisco, CA, USA.
- Boot, C.M., A. Koyama, K. Buckeridge, S.M. Schaeffer, J. Ernakovich, J.P. Schimel, M.D. Wallenstein. 2015. Microbial community dynamics and relationship with biogeochemical cycling across seasons in Arctic tundra. The 100th Annual Ecological Society of America Meeting, Baltimore, MD, USA.
- Koyama, A., N.G. Johnson, E. Rosenlieb, C.T. Web, J.C. von Fischer. 2014. Microbial and environmental control on sensitivity of methane uptake to increased ammonium concentrations in grassland soils across the US Great Plains. 2014. 6th Annual Argonne Soil Metagenomics Meeting, St. Charles, IL, USA.
- Carrillo, Y., C. Bell, C.M. Boot, A. Koyama, M.D. Wallenstein, E. Pendall. 2014. Linking plant species and their rhizosphere traits with soil carbon priming in situ. The 99st Annual Ecological Society of America Meeting, Sacramento, CA, USA.
- Alster, C.J., A. Koyama, N.G. Johnson, J.C. von Fischer. 2014. Assessing the relative importance of microbial versus abiotic factors for an ecosystem function: An evaluation of soil respiration rates from three grassland soils reciprocally transplanted with microbial communities. The 99st Annual Ecological Society of America Meeting, Sacramento, CA, USA.
- Johnson, N.G., A. Koyama, J.C. von Fischer, C.T. Webb. 2014. A Bayesian hierarchical approach for estimating microbial community compositions assessed using two sets of primers via polymerase chain reaction. The 99st Annual Ecological Society of America Meeting, Sacramento, CA, USA.
- Koyama, A., M.D. Wallenstein, J.C. Moore and R.T. Simpson. 2012. Potential enzyme activities altered by increased nutrient availability in Arctic tundra soils. American Geophysical Union Fall Meeting, San Francisco, CA, USA.
- Jourgensen, R.L., A. Koyama, J.C. von Fischer, and M. Gupata. 2012. Exploring the potential of an isotopic N2O analyzer capable of real-time measurements. American Geophysical Union Fall Meeting, San Francisco CA, USA.
- Wang, X., Q. Mao, L. Qu, Y. Tamai, A. Koyama, M. Watanabe, K. Kita, T. Koike. 2012. Effects of nitrogen deposition combined with phosphorus deficiency on fine-root growth of three larch species. The International Society of Root Research, Dundee, Scotland.
- Koyama, A., R.D. Evans. 2011. Processes leading to increased soil organic carbon in a Mojave Desert ecosystem under elevated CO2. American Geophysical Union Fall Meeting, San Francisco CA, USA.
- Sonderegger, D., A. Koyama, V. Jin, S.A. Billings, K. Ogle, R.D. Evans. 2011. Leaf δ15N and δ13C as temporal integrators of biogeochemical processes at the Mojave Desert FACE experiment. American Geophysical Union Fall Meeting, San Francisco CA, USA.
- Evans, R.D., A. Koyama, D. Sonderegger, TN Charlet, B. Newingham, LF Fenstermaker, K. Ogle, S. Smith, B. Nowak. Whole-ecosystem exposure to elevated CO2 increases total ecosystem C in the Mojave Desert. American Geophysical Union Fall Meeting, San Francisco CA, USA.
- Stephan, K., K.L. Kavanagh, A. Koyama, 2007. Influence of fire severity on watershed nitrogen cycling using 15N natural abundance in terrestrial and aquatic ecosystem components. American Geophysical Union Fall Meeting, San Francisco CA, USA.
- Koyama, A., S.D. Smith, R.S. Nowak, R.D. Evans. 2008. Soil organic carbon balance in a desert ecosystem after 10 years exposure to elevated carbon dioxide. American Geophysical Union Fall Meeting, San Francisco CA, USA.
- Koyama, A., K. Stephan and K.L. Kavanagh. 2006. Fire effects on soil N transformations in central Idaho coniferous forests – Prescribed fires vs. wildfires. Poster presented in 3rd International Fire Ecology and Management Congress, San Diego, CA.
- Thompson, M., A. Koyama, K. Stephan and K.L. Kavanagh. 2006. Effects of wildfire on hydraulic properties in conifers. Poster presented in 3rd International Fire Ecology and Management Congress, San Diego, CA.
- Stephan, K., A. Koyama, K.L. Kavanagh. 2006. Comparison of wildfire and spring prescribed burn effects on nitrogen dynamics in Rocky Mountain headwater areas. Paper presented in 3rd International Fire Ecology and Management Congress, San Diego, CA.
- Koyama, A., M. Thompson, K. Stephan, K.L. Kavanagh. 2006. Fire effects on carbon dynamics in central Idaho coniferous forests. Poster presented at the 91st Annual Ecological Society of America Meeting, Memphis, TN.
- Stephan, K., A. Koyama, K.L. Kavanagh. 2006. Comparison of wildfire and prescribed burn effects on nitrogen dynamics in headwater ecosystems in central Idaho. Paper presented at the 91st Annual Ecological Society of America Meeting, Memphis, TN.
- Stephan, K., A. Koyama, K.L. Kavanagh. 2005. Fire effects on nitrogen dynamics in headwater systems. Paper presented in 90th Annual Ecological Society of America Meeting, Montreal, Quebec, Canada.
- Koyama, A., K. Stephan, K.L. Kavanagh. 2004. Ash effects on nitrogen dynamics in soils and plants after a wildfire. Poster presented at the 88th Annual Ecological Society of America Meeting, Portland, OR.
- Stephan, K., A. Koyama, K.L. Kavanagh. 2004. Fire effects on nitrogen concentration and nitrogen isotopic composition in riparian and upslope plants of headwaters. Poster presented at the 88th Annual Ecological Society of America Meeting, Portland, OR.
- Koyama A., K.L. Kavanagh, A. Robinson. 2001. Evidence supporting the legacy of marine-derived nitrogen in riparian forests of Central Idaho. Paper presented at the 86th Annual Ecological Society of America Meeting, Madison, WI.
Awards
2002: Outstanding Graduate Student of Forest Resources, College of Natural Resources, University of Idaho
2001: Travel Award for Salmon Nutrient Conference in Eugene, Oregon, from American Fisheries Society. $450
1999: International Student Tuition Waiver, from International Program Office. $1500
Professional Societies
American Geophysical Union
Ecological Society of America
Soil Ecology Society
Manuscript Reviewer for Scientific Journals
Global Change Biology (4), Biogeochemistry (4), Oecologia (3), Canadian Journal of Microbiology (2), Ecosystems (1), Forest Ecology and Management (1), FEMS Microbiology Ecology (1), Science of Total Environment (1), PLoS ONE (2), International Journal of Wildland Fire (1), Soil Biology and Biochemistry (5), Biogeosciences (1), Ecological Indicators (1), World Journal of Microbiology and Biotechnology (1), Western North American Naturalist (1), Plant and Soil (1)
My Publon profile:
https://publons.com/author/655781/akihiro-koyama#profile
Proposal Reviewer for Scientific Organizations
2014: Long Term Research in Environmental Biology, National Science Foundation, USA (Mail-in)
2015: Environmental System Science, Arctic Panel, Department of Energy, USA
2015: National Science Centre, Poland (Mail-in)
Extra-Curricular Activities
2013: Organizing committee for Front Range Isotope Day (FRIDay), Natural Resource Ecology Laboratory, Colorado State University
2012-2013: Selection committee of Francis Clark Scholarship and James E. Ellis Memorial Scholarship, Natural Resource Ecology Laboratory, Colorado State University
2012: Post-doctoral fellow search committee for Department of Biology, Colorado State University
2002-2003: Representative of graduate students, Department of Forest Resources for College of Natural Resources Redesign Committee, University of Idaho
2002-2003: Representative of graduate students, Department of Forest Resources for University of Idaho Graduate Student Association
2000-2001: Facilitated and participated in International Student Orientation, University of Idaho
1999-2000: President of Japanese Student Association, University of Idaho
Aerial view of experimental plots near Toolik Lake, Alaska.
The Arctic i