PhD position to study water stress indicators of riparian forest decline

Seeking a PhD student to work on a new NSF-funded project with field work  on a Southern California river (Santa Clara) plus dendro-isotope lab analyses.  Three years of funding minimum available, with additional years possible.


Linking basin-scale, stand-level, and individual tree water stress indica tors for groundwater-dependent riparian forests in multiple-use river basins


The PhD position is supported at SUNY-ESF, the State University of New Yo rk College of Environmental Science and Forestry, working with Dr. John Stella and interdisciplinary collaborators at UC Santa Barbara and The Nature Conser vancy. The position will start in fall 2017. Research questions will focus on ripari an ecosystem response to drought, climate change and groundwater extraction. Methods w ill include field sampling to inventory riparian forest structure and health, collect ing and analyzing tree rings for growth trends and annual water use efficiency using carbon  isotopes, and assessing critical thresholds for riparian forest decline. Field studies  will occur in the Santa Clara River basin in Southern California with lab work at SUNY-ESF  and partner institutions. Ideal candidates will have an MS in ecology, environmental  science, or a related field; a strong quantitative and statistical background; the abil ity to work in remote field settings; and interest in riparian forest ecology and tree e cophysiology in dryland regions. The position is funded for a minimum of three years and  provides a competitive stipend, tuition and benefits. Interested candidates should s end a CV/resume (with GPA and GRE scores), a description of research interests and experience, and names and contact information for 3 references to stella@ For more information on how to apply, see


Linking basin-scale, stand-level, and individual tree water stress indica tors for groundwater-dependent riparian forests in multiple-use river basins John Stella, SUNY-ESF (PI); Michael Singer, UCSB (PI); Dar Roberts, UCSB (Co-PI)

This project will develop a suite of water stress indicators at several s cales to assess the health of riparian ecosystems in response to sustained groundwater decline. Riparian forests and woodlands are hotspots of biodiversity and support k ey functions and habitats within river corridors, but they are particularly sensitive  to large changes in water supply. The study will take place in the Santa Clara River (Califor nia, USA), where sustained groundwater pumping for irrigation during a severe drought has  had negative impacts and allows for study of riparian woodland response to short- and long-term climate change. The project team will assess the signals and thresholds o f water stress over the last decade using high-resolution aerial imagery and tree-rings  to develop predictors of long-term impairment and collapse. This work addresses a to pic of urgent scientific and societal importance, namely how to assess and prevent nega tive impacts of drought and human-induced water shortages on vulnerable, high-value riparian ecosystems. In collaboration with The Nature Conservancy, the project tea m will integrate results within statewide guidelines for protecting groundwater-dependent riparian ecosystems mandated under California=92s recent Groundwater Sustainability Management Act. The project will engage the public in several ways, including: 1) consulting with groundwater managers, farmers and other stakeholders through workshops to develop effective methods for communicating results widely; (2) mentoring early career scientists including women in STEM subjects; and 3) engaging with K-12 student programs in diverse local communities to increase environmental awareness in the Santa Clara basin.

As water management in multiple-use river basins around the world becomes increasingly intertwined with large-scale ecosystem restoration, the prop osed research sits at the forefront of broader human-climate-ecosystem challenges facin g societies, businesses, and governments. The project will capitalize on extensive gro undwater well records to link water table dynamics with changes in plant water status d etected at two different scales: (1) basin-wide, high-resolution aerial imagery taken se asonally during the drought; and (2) annual growth and carbon isotope data from tree ring s covering the same period. The study is novel, in that it integrates advanced metho ds in two rapidly-emerging fields, hyperspectral remote sensing and isotope dendroe cology, in developing a holistic understanding of water stress at multiple scales of  resolution. The research is also potentially transformative in that it compares water str ess indicators that vary in their timing, strength, and rates of change, and that it ena bles the assessment of warning signs and time lags between reduced growth and func tioning in individual trees, and synoptic forest decline evident throughout a river  corridor. These findings will have broad application beyond the study system, because the  ecology and functional roles of riparian trees are similar in many water-limited regi ons, with similar foundational importance in groundwater-dependent ecosystems globally.