Water stress indicators and ecohydrologic change in riparian woodlands
Human demand on water resources, particularly groundwater, is high in arid-land river basins where significant withdrawals occur for intensive agriculture and industry. The interaction between groundwater extraction by humans and drought and climate change, such as that which is currently affecting large areas of the U.S. Southwest and southern Europe, can result in rapidly declining water tables with strongly negative consequences for groundwater-dependent ecosystems (GDEs). Riparian trees including willows, cottonwoods and other poplars, are particularly sensitive to drought, climate change, and declining groundwater water levels, with reduced growth, vigor, and physiological function. These conditions, if they persist, lead to riparian forest decline, with substantial risks to the ecosystems they support and the services they provide to society.
Together with collaborators at Cardiff University, UC Santa Barbara, and CNRS (France), our lab is developing a suite of multi-disciplinary water stress indicators for riparian forests to assess the impacts of hydrologic change from both natural causes and human manipulation. We have several projects in the Southwestern U.S. and the Rhône River Basin (France), with funding from the National Science Foundation and SERDP, the U.S. Strategic Environmental Research and Development Program. Our approach is to couple field-based tree-ring research, stable isotope analysis, and high-resolution remote sensing to calibrate water stress indicators across a range of geographic scales from individual trees to forest stands to an entire riparian corridor. The ultimate goal of the project is to identify trends and thresholds in forest response to groundwater decline and drought that can be used to protect groundwater-dependent ecosystems in multiple-use river basins.
Collaborators:
Related publications: (* indicates student contributors)
Hultine, K.R., K.C. Grady, T.E. Wood, S.M. Shuster, J.C. Stella, T.G. Whitham. 2016. Climate change perils for dioecious plant species. Nature Plants. 10.1038/nplants.2016.109
Stella, J.C., J. Riddle*, H. Piégay, M. Gagnage*, M-L. Trémélo. 2013. Climate and local geomorphic interactions drive patterns of riparian forest decline along a Mediterranean Basin river. Geomorphology. DOI: 10.1016/j.geomorph.2013.01.013 [pdf]
Stella, J.C., P. Rodríguez-González, S. Dufour, J. Bendix. 2013. Riparian vegetation research in Mediterranean-climate regions: common patterns, ecological processes, and considerations for management. Hydrobiologia 719:291–315. DOI: 10.1007/s10750-012-1304-9
Singer, M.B., J.C. Stella, S. Dufour, L.B. Johnstone*, H. Piégay, and R.J.S. Wilson.2012. Contrasting water uptake and growth responses to drought in co-occurring riparian tree species. Ecohydrology. DOI: 10.1002/eco.1283 [pdf]
Schifman, L.A.*, J.C. Stella, M. Teece and T.A. Volk. 2012. Plant growth and water stress response of hybrid willow (Salix spp.) among sites and years in central New York. Biomass & Bioenergy 36: 316-326 DOI:10.1016/j.biombioe.2011.10.042 [pdf]
Stella, J.C., and J.J. Battles. 2010. How do riparian woody seedlings survive seasonal drought? Oecologia 164:579–590. DOI 10.1007/s00442-010-1657-6 [pdf]
Together with collaborators at Cardiff University, UC Santa Barbara, and CNRS (France), our lab is developing a suite of multi-disciplinary water stress indicators for riparian forests to assess the impacts of hydrologic change from both natural causes and human manipulation. We have several projects in the Southwestern U.S. and the Rhône River Basin (France), with funding from the National Science Foundation and SERDP, the U.S. Strategic Environmental Research and Development Program. Our approach is to couple field-based tree-ring research, stable isotope analysis, and high-resolution remote sensing to calibrate water stress indicators across a range of geographic scales from individual trees to forest stands to an entire riparian corridor. The ultimate goal of the project is to identify trends and thresholds in forest response to groundwater decline and drought that can be used to protect groundwater-dependent ecosystems in multiple-use river basins.
Collaborators:
- Michael Singer (Cardiff University)
- Dar Roberts (UC Santa Barbara)
- Kelly Caylor (UC Santa Barbara)
- Hervé Piégay (French National Centre for Scientific Research)
- The Nature Conservancy (California chapter)
- Riparian Invasion Research Lab (UC Santa Barbara)
Related publications: (* indicates student contributors)
Hultine, K.R., K.C. Grady, T.E. Wood, S.M. Shuster, J.C. Stella, T.G. Whitham. 2016. Climate change perils for dioecious plant species. Nature Plants. 10.1038/nplants.2016.109
Stella, J.C., J. Riddle*, H. Piégay, M. Gagnage*, M-L. Trémélo. 2013. Climate and local geomorphic interactions drive patterns of riparian forest decline along a Mediterranean Basin river. Geomorphology. DOI: 10.1016/j.geomorph.2013.01.013 [pdf]
Stella, J.C., P. Rodríguez-González, S. Dufour, J. Bendix. 2013. Riparian vegetation research in Mediterranean-climate regions: common patterns, ecological processes, and considerations for management. Hydrobiologia 719:291–315. DOI: 10.1007/s10750-012-1304-9
Singer, M.B., J.C. Stella, S. Dufour, L.B. Johnstone*, H. Piégay, and R.J.S. Wilson.2012. Contrasting water uptake and growth responses to drought in co-occurring riparian tree species. Ecohydrology. DOI: 10.1002/eco.1283 [pdf]
Schifman, L.A.*, J.C. Stella, M. Teece and T.A. Volk. 2012. Plant growth and water stress response of hybrid willow (Salix spp.) among sites and years in central New York. Biomass & Bioenergy 36: 316-326 DOI:10.1016/j.biombioe.2011.10.042 [pdf]
Stella, J.C., and J.J. Battles. 2010. How do riparian woody seedlings survive seasonal drought? Oecologia 164:579–590. DOI 10.1007/s00442-010-1657-6 [pdf]