Darius received a B.S. in Geology from The University of Minnesota (1995), an M.S. in Geology (emphasis in Geomorphology) from Northern Arizona University (1998), and a Ph.D. in Watershed Management (minor in Remote Sensing and Spatial Analysis) from The University of Arizona (2004). From 2004-2007, he was a postdoctoral fellow with the U.S. Environmental Protection Agency, Office of Research and Development. During this time he was also an adjunct professor and part-time instructor in the Department of Landscape Architecture at the University of Nevada, Las Vegas. He joined the Rocky Mountain Geographic Science Center in 2008 as a research physical scientist. His current research interests include the development of new methods and tools for the assessment and valuation of ecosystem goods and services - the specific benefits that we derive from nature. More specifically, his work involves developing methods and tools that can account for the spatial and temporal dynamics of service production and incorporate that and other information into more rigorous analyses of the tradeoffs associated with landscape management. Darius is the USGS Co-Director of the Science Impact Laboratory for Policy and Economics (SILPE) at the University of New Mexico.
Lopez-Hoffman, L., R. Wiederholt, C. Sansone, K. Bagstad, P. Cryan, J. Diffendorfer, J. Goldstein, K. LaSharr, J. Loomis, G. McCracken, R. Medellin, A. Russell, and D. Semmens, In Press. Market forces & technological substitutes can cause declines in the value of bat pest-control services for cotton. PLoS One, 9(2): e87912. doi:10.1371/journal.pone.0087912
Diffendorfer, J., J. Loomis, L. Ries, K. Oberhauser, L. Lopez-Hoffman, D. Semmens, B. Semmens, B. Butterfield, K. Bagstad, J. Goldstein, R. Wiederholt, B. Mattsson, and W. Thogmartin, 2013. National valuation of monarch butterflies indicates an untapped potential for incentive-based conservation. Conservation Letters, doi: 10.1111/conl.12065.
Sherrouse, B.C., D.J. Semmens, and J.M. Clement, 2014. An application of Social Values for Ecosystem Services (SolVES) to three national forests in Colorado and Wyoming. Ecological Indicators, 36:68-79.
Wiederholt, R., L. Lopez-Hoffman, J. Cline, R. Medellin, J. Diffendorfer, D. Semmens, P. Cryan, A. Russell, and G. McCracken, 2013. Moving across the border: Modeling migratory bat populations. Ecosphere 4(9), p. 1-16.
Haines, S. S., Diffendorfer, J. E., Balistrieri, L., Berger, B., Cook, T., DeAngelis, D., Doremus, H., Gautier, D. L., Gallegos, T., Gerritsen, M., Graffy, E., Hawkins, S., Johnson, K. M., Macknick, J., McMahon, P., Modde, T., Pierce, B., Schuenemeyer, J. H., Semmens, D., Simon, B., Taylor, J., Walton-Day, K., 2013. A Framework for Quantitative Assessment of Impacts Related to Energy and Mineral Resource Development, Natural Resources Research, 23(1):3-17.
Bagstad, K.J., D.J. Semmens, S. Waage, R. Winthrop, 2013. A comparative assessment of decision-support tools for ecosystem services quantification and valuation, Ecosystem Services, 5:27-39.
Bagstad, K.J., D.J. Semmens, R. Winthrop, 2013. Comparing approaches to spatially explicit ecosystem service modeling: A case study from the San Pedro River, Arizona, Ecosystem Services, 5:40-50.
Bagstad, K.J., D. Semmens, R. Winthrop, D. Jordahl, and J. Larson, Forthcoming. Ecosystem services valuation to support decision-making on public lands: A case study for the San Pedro River, Arizona. USGS Scientific Investigations Report.
Lopez-Hoffman, L., D. Semmens, and J. Diffendorfer, 2013. How do migratory species add ecosystem service value to wilderness? Calculating the spatial subsidies provided by protected areas. International Journal of Wilderness, 19(1):14-19.
Goodrich, D.C., I.S. Burns, C.L. Unkrich, D.J. Semmens, D.P. Guertin, M. Hernandez, S. Yatheendradas, and J.R. Kennedy, 2013. KINEROS2/AGWA: Model use, calibration and validation. Special issue of Transactions of the ASABE, 55(11):1561-1574.
Bagstad, K.J., D.J. Semmens, and C. van Riper, III., 2012. Ecosystem services science and policy in arid and semiarid environments: Opportunities and challenges for the Colorado Plateau. Pp. 61-79 in: The Colorado Plateau V: Research, environmental planning, and management for effective conservation. C. van Riper, III, M.L. Villarreal, C.J. van Riper, and M.J. Johnson, eds. University of Arizona Press: Tucson.
Kareiva, P., M. Ruckelshaus, K. Arkema, G. Geller, E. Girvetz, D. Goodrich, E. Nelson, V. Matzek, M. Pinsky, W. Reid, M. Saunders, D. Semmens, and H. Tallis, 2012. Impacts of Climate Change on Ecosystem Services. Chapter 4 in Staudinger, M.D., N.B. Grimm, A. Staudt, S.L. Carter, F.S. Chapin III, P. Kareiva, M. Ruckelshaus, and B.A. Stein. 2012. Impacts of Climate Change on Biodiversity, Ecosystems, and Ecosystem Services: Technical Input to the 2013 National Climate Assessment. Cooperative Report to the 2013 National Climate Assessment. 296 p. Available at: http://assessment.globalchange.gov
Semmens, D.J., Diffendorfer, J.E., Lopez-Hoffman, L., and Shapiro, C.S., 2011. Accounting for the ecosystem services of migratory species: Quantifying migration support and spatial subsidies. Ecological Economics, 70(12):2236-2242.
Sherrouse, B.C., Clement, J.M., and Semmens, D.J. 2011. A GIS application for assessing, mapping, and quantifying the social values of ecosystem services. Applied Geography 31: 748-760.
Norman, L.M., H. Huth, L. Levick, I.S. Burns, D.P. Guertin, F. Lara-Valencia, and D.J. Semmens, 2010. Flood Hazard Awareness and Hydrologic Modeling at Ambos Nogales, US-Mexico Border. Journal of Flood Risk Management, 3:2, 151-165.
Hernandez, M., W. Kepner, D. Goodrich, and D. Semmens, 2010. The Use of Scenario Analysis to Assess Water Ecosystem Services in Response to Future Land Use Change in the Willamette River Basin, Oregon. NATO Security through Science Series, Springer Publishers, The Netherlands
Mahmoud, M., Y. Liu, H. Hartmann, S. Stewart, T. Wagener, D. Semmens, R. Stewart, H. Gupta, D. Dominguez, F. Dominguez, D. Hulse, R. Letcher, B. Rashleigh, C. Smith, R. Street, J. Ticehurst, M. Twery, H. van Delden, R. Waldick, D. White, and L. Winter, 2009. A formal framework for Scenario Development to support environmental decision making. Environmental Modeling and Software, 24:7, 798-808.
Semmens, D.J., J.S. Briggs, and D.A. Martin, 2008, An ecosystem services framework for multi-disciplinary research in the Colorado River headwaters. Proceedings of the Third Interagency Conference on Research in the Watersheds, 8-11 September 2008, Estes Park, CO, USGS Scientific Investigations Report 2009-5049. http://pubs.usgs.gov/sir/2009/5049/pdf/Semmens.pdf
Webb, R.M.T., and Semmens, D.J., eds., 2009, Planning for an uncertain future—Monitoring, integration, and adaptation. Proceedings of the Third Interagency Conference on Research in the Watersheds: U.S. Geological Survey Scientific Investigations Report 2009-5049, 292 p.
Levick, L.R., D.C. Goodrich, M. Hernandez, J. Fonseca, D.J. Semmens, J. Stromberg, M. Tluczek, R.A. Leidy, M. Scianni, D.P. Guertin, and W.G. Kepner, 2008. The Ecological and Hydrological Significance of Ephemeral and Intermittent Streams in the Arid and Semi-Arid American Southwest. Report EPA/600/R-08/134, or ARS/233046.
Kepner, W.G., D.J. Semmens, M. Hernandez, and D.C. Goodrich. 2008. Evaluating Hydrological Response to Forecasted Land-use Change. Chapter 15 in Special Issue of Association of American Geographers. North American Land Cover Summit. Washington, DC. pp. 275-292. ISBN 978-0-89291-271-1.
Liu, Y., Mahmoud, M., Hartmann, H., Stewart, S., Wagener, T., Semmens, D., Stewart, R., Gupta, H., Dominguez, D., Hulse, D., Letcher, R., Rashleigh, B., Smith, C., Street, R., Ticehurst, J., Twery, M., van Delden, H., Waldick, R., White, D., and Winter, L., 2008. Formal scenario development for environmental impact assessment studies. In Jakeman, A., A. Voinov, A. E. Rizzoli, and S. Chen, (Eds.) Environmental Modelling, Softeare and Decision Support, 3. IDEA Book Series, Elsevier, 338 pp.
Semmens, D.J., D.C. Goodrich, C.L. Unkrich, R.E. Smith, D.A. Woolhiser, and S.N. Miller, 2008. KINEROS2 and the AGWA modeling framework; in Wheater, H., S. Sorooshian, and K.D. Sharma, (Eds.) Hydrological Modelling In Arid and Semi-Arid Areas, Cambridge University Press, New York, 206pp.
Kepner, W.G., M. Hernandez, D.J. Semmens, and D.C. Goodrich. 2008. The Use of Scenario Analysis to Assess Future Landscape Change on Watershed Condition in the Pacific Northwest (USA). In Use of Landscape Sciences for Environmental Security, NATO Security through Science Series, Springer Publishers, The Netherlands. ISBN 978-1-4020-6588-0, pp. 237-261.
Miller, S.N., Semmens, D.J., Goodrich, D.C., Hernandez, M., Miller, R.C., Kepner, W.G., and Guertin, D.P., 2007, The Automated Geospatial Watershed Assessment tool; Environmental Modeling and Software, v. 22, n. 3, p. 365-377.
Nikolova, M., S. Nedkov, D. Semmens, and S. Iankov, 2007. Environmental quality and landscape-risk assessment in the Yantra River Basin; In W. Kepner, F. Müller, I. Petrosillio, B. Jones, K. Krauze, S. Victorov, and G. Zurlini, (eds.) Use of Landscape Sciences for the Assessment of Environmental Security, NATO Security Through Science Series, Springer Publications, p. 202-217.
Kepner, W.G., Semmens, D.J., Basset, S.D., Mouat, D.A., Goodrich, D.C., 2004, Scenario analysis for the San Pedro River, analyzing hydrological consequences for a future environment. Environmental Modeling and Assessment, v. 94, p. 115-127.