About

Emily S. Bernhardt is an ecosystem ecologist and biogeochemist whose research is principally concerned with tracking the movement of elements through ecological systems. Her work aims to document the extent to which the structure and function of aquatic ecosystems are being altered by land use change, including urbanization, agriculture, and mining, as well as by global change factors such as rising CO2 levels and sea levels, and chemical pollution. This research is essential for understanding how ecosystem change can be mitigated or prevented through active ecosystem management. Dr. Bernhardt holds the position of James B. Duke Distinguished Professor of Biology at Duke University, where she has been a faculty member since 2016. She is also the Chair of the Department of Biology and a Professor of Marine Science and Conservation at the Nicholas School of the Environment. Her academic career includes a Ph.D. from Cornell University and a B.S. from the University of North Carolina, Chapel Hill. Her contributions extend to her roles in various initiatives, including the Duke Initiative for Science & Society, and she has been recognized for her leadership and research in environmental science.

Research topics

• Ecology
• Environmental science
• Biology
• Environmental chemistry
• Chemistry
• Geology
• Geography
• Computer Science
• Environmental engineering
• Meteorology
• Mathematics
• Atmospheric sciences
• Microbiology
• Environmental protection
• Agroforestry

Selected publications

• Connecting the past with restoration futures: integrating legacy thinking into environmental decision making

  Environmental Research Letters · 2025-02-18 · 1 citations

  articleOpen access

  Connecting the past with restoration futures: integrating legacy thinking into environmental decision making, Basu, Nandita B, Meter, K J Van, Bennett, Elena, Bernhardt, Emily, Inamdar, Shreeram, McCrackin, Michelle

  PublisherOA PDFDOI

• Overlooked and extensive ghost forest formation across the US Atlantic coast

  Research Square · 2025-05-08

  preprintOpen access
  PublisherOA PDFDOI

• Community structure and metals concentration together determine aquatic-to-terrestrial metal subsidies in urban and forested streams

  Freshwater Science · 2025-03-28 · 1 citations

  articleSenior author

  Watershed urbanization leads to a characteristic set of physical, biological, and chemical stressors that reduce the biological diversity of aquatic insect communities. We examined how aquatic-to-terrestrial subsidies of energy and associated trace metals in emergent aquatic insects differed between 2 segments of an urban stream, 1 above (stormwater) and 1 below (wastewater) a wastewater treatment facility, and a nearby forested stream. We conducted monthly sampling of emergent aquatic insects over 1 y and analyzed concentrations of 3 trace metals (Cu, Zn, and Se). The wastewater-impacted stream transported 13 to 14% more biomass, 17 to 52% more Zn, and 13 to 42% more Cu than the stormwater and forested streams. In contrast, the forested stream transported higher annual fluxes of Se relative to the urban sites. Emergence timing also differed between sites. During spring (April–June), 68% and 72% of annual emergence occurred in the forested and stormwater-impacted sites, respectively. In contrast, emergence was distributed across the year at the wastewater-impacted stream, with only 49% of emergence occurring during spring. Taxa highly tolerant of disturbance, multivoltine Chironomidae, accounted for 50 to 85% of total biomass and 61 to 91% of the total metal flux at the urban sites. In contrast, Chironomidae accounted for only 44% of total biomass and 57% of the total metal flux at the forested site. The metal body burden of emergent insects varied throughout the year, with Zn changing by >400% in Chironomidae at the urban sites. We compared the median Zn and Cu body metal burdens in emergent insect adults at the sites, which were in North Carolina, USA, with those from more heavily impacted streams in the Colorado Mineral Belt and found that they were remarkably comparable, despite site differences in water and algal metal concentrations. Biological community dynamics alter the timing, magnitude, and composition of insect biomass and metal export. In urban, impacted streams, altered composition and phenology of emergent insect communities can increase metal flux, posing elevated risk to consumers in paired riparian and terrestrial environments.

  PublisherDOI

• Author Correction: User-focused evaluation of National Ecological Observatory Network streamflow estimates

  UNC Libraries · 2025-03-01

  articleOpen access
  PublisherDOI

• StreamPULSE Sensor Data and Metabolism Estimates for Rivers and Streams

  HydroShare Resources · 2025-07-05

  datasetSenior author
  PublisherDOI

• Forest recovery after deforestation is fueled by mineral weathering at the expense of ecosystem buffering capacity

  Proceedings of the National Academy of Sciences · 2025-10-17 · 2 citations

  articleOpen access1st authorCorresponding

  The pace and trajectory of ecosystem development are governed by the availability and cycling of limiting nutrients, and anthropogenic disturbances such as acid rain and deforestation alter these trajectories by removing substantial quantities of nutrients via titration or harvest. Here, we use six decades of continuous chemical and hydrologic data from three adjacent headwater catchments in the Hubbard Brook Experimental Forest, New Hampshire—one deforested (W5), one CaSiO 3 -enriched (W1), and one reference (W6)—to quantify long-term nutrient and mineral fluxes. Acid deposition since 1900 drove pronounced depletion and export of base cations, particularly calcium, across all watersheds. Experimental deforestation of W5 intensified loss of biomass and nutrient cations and triggered sustained increases in streamwater pH, Ca 2+ , and SiO 2 exports over nearly four decades, greatly exceeding the effects of direct CaSiO 3 enrichment in both duration and magnitude. We detect no long-term changes in water yield or water flow paths in the experimental watersheds, and we attribute this multidecadal increase in weathering rates following deforestation to biological responses to severe nutrient limitation. Our evidence suggests that in the regrowing forest, plants are investing photosynthate into belowground processes that amplify mineral weathering to access phosphorus and micronutrients, consequently elevating the export of less limiting elements present in silicate parent material. Throughout decades of forest regrowth, enhanced biotic weathering has continued to deplete the acid buffering capacity of the terrestrial ecosystem while the export of weathering products has elevated the pH of the receiving stream.

  PublisherOA PDFDOI

• Author Correction: User-focused evaluation of National Ecological Observatory Network streamflow estimates

  UNC Libraries · 2025-03-01

  articleOpen access
  PublisherDOI

• Overlooked and extensive ghost forest formation across the US Atlantic coast

  Nature Sustainability · 2025-12-03 · 4 citations

  article
  PublisherDOI

• Long-term change in the concentration-discharge relationship reveals controls on watershed exports of dissolved organic carbon

  2025-07-18

  article

  Dissolved organic carbon (DOC) export from watersheds by streams is an important, changing component of the global carbon cycle. We examined the controls on DOC export by quantifying changes in the DOC concentration-discharge relationship from 1992 through 2022 for nine forested headwater catchments at the Hubbard Brook Experimental Forest in the northeastern United States. We observed a strong increase in the intercept of the log-log concentration-discharge relationship between 2005 and 2017 and a weak increase in the slope of that relationship between 2002 and 2021, along with seasonal and watershed-level differences. The intercept, which indicates the average stream DOC concentration at a given discharge, was strongly and inversely related to ionic strength of the soil solution as predicted by electrolyte solubility theory. This relationship varied among watersheds, perhaps because of soil pH. The intercept was not strongly related to annual precipitation or air temperature. DOC export ranged from 13 to 153 kg C ha-1 y-1 among study watersheds and years, and was correlated with annual precipitation and discharge. Historical data suggest that DOC export has probably increased over the past 50 years, likely due both to increases in precipitation and runoff and to increases in the intercept and slope of the concentration-discharge relationship. Our results suggest the potential for long-term legacy effects of acidification on DOC solubility and stream DOC concentrations in acid-sensitive watersheds, despite reductions in acid deposition, as mineral weathering slowly replenishes the ionic strength of soil solutions.

  PublisherDOI

• Surface elevation trends in natural and restored coastal forested wetlands reveal vulnerability to saltwater intrusion and sea level rise

  Research Square · 2025-06-18 · 2 citations

  preprintOpen accessSenior author
  PublisherOA PDFDOI

Recent grants

• Collaborative Proposal: Coupled C, N and S cycling in coastal plain wetlands: how will climate change and salt water intrusion alter ecosystem dynamics?

  NSF · $520k · 2010–2013

• MRA: Continental scale controls on instream and catchment contributions to greenhouse gas fluxes from rivers

  NSF · $699k · 2021–2026

• CAREER: Potential for the Recovery of Biogeochemical Function in Degraded Stream Ecosystems

  NSF · $627k · 2006–2011

• Collaborative Research: MRA: MACRO-Sheds: Comparative Ecosystem Biogeochemistry at Continental Scales

  NSF · $699k · 2019–2025

• Streams in urbanizing landscapes: from syndrome diagnosis to watershed prescription

  NSF · $560k · 2013–2018

Frequent coauthors

• Matthew Ross

  Colorado State University

  194 shared

• Michael Vlah

  Duke University

  176 shared

• Amanda Delvecchia

  171 shared

• Spencer Rhea

  Duke University

  164 shared

• Audrey Thellman

  Duke University

  163 shared

• Nick Gubbins

  161 shared

• Stuart E. Bunn

  Griffith University

  102 shared

• Clifford N. Dahm

  University of New Mexico

  102 shared

Labs

• Bernhardt LabPI

Awards & honors

• Cary Institute of Ecosystem Studies Research Principal Inves…
• Cary Institute of Ecosystem Studies Research Principal Inves…
• National Institute of Environmental Health Sciences LTREB: S…