joanna blaszczak

Joanna Blaszczak

Associate Professor, Freshwater Ecology & Biogeochemistry

Summary

I am interested in the transport and transformation of nutrients and contaminants through watersheds and the streams that drain them. I use a combination of field, laboratory, and modeling approaches to test ecological theory and controls on water quality in human-dominated landscapes.

A central goal of my research is to improve understanding of how increasing hydroclimatic variability and land use change in the Anthropocene will alter the capacity of watersheds and freshwater ecosystems to retain, transform, and alter novel chemical mixtures. In previous research, I investigated the effects of multiple stressors in urban watersheds (e.g. contamination, excess nutrients, increased extremes in hydrologic flow regimes) as fundamental drivers of stream ecosystem function.

Questions that guide my current and future work include:

  1. What is the role of novel chemical regimes (i.e. ‘chemical cocktails’) in shaping the response of freshwater ecosystems to land use change?
  2. How do changes in watershed land use and hydrologic connectivity alter the chemical regimes of freshwater ecosystems?
  3. What processes determine the magnitude and timing of freshwater ecosystem energetics and how are ecosystem energetics changing in the Anthropocene?

Education

B.S. Cornell University, 2011
Ph.D. Duke University, 2018

Publications

Datasets

Journals

Fire influence on land–water interactions in aridland catchments

2025

BioScience, Volume 75, Issue 1, January 2025, Pages 30–46

Tamara K Harms, Heili Lowman, Joanna Blaszczak, Ashley Cale, Xiaoli Dong, Stevan Earl, Leah Gaines-Sewell, Julia Grabow, Erin Hanan, Marina Lauck, John Melack, Ann Marie Reinhold, Betsy M Summers, Alex J Webster, Nancy B Grimm

Persistent and lagged effects of fire on stream solutes linked to intermittent precipitation in arid lands

2024

Biogeochemistry Letters, Volume 167, pages 777–791, (2024)

Lowman, H., Blaszczak, J.R., Cale, A., Dong, X., Earl, S., Grabow, J., Grimm, N.B., Harms, T.K., Melack, J., Reinhold, A.M., Summers, B., and Webster, A.J.

Precipitation influences the timing and intensity of the effects of fire on stream solute dynamics in aridland watersheds, but these responses vary by climate, solute, and watershed characteristics....

Reviews