Dr. Andrew Juhl

Lamont Research Professor, Lamont-Doherty Earth Observatory (LDEO), Columbia Climate School

Associate Director, Biology and Paleo Environment, Lamont-Doherty Earth Observatory (LDEO)

Columbia Climate School

122 Marine Biology
P.O. Box 1000
61 Route 9W
Palisades, NY 10964


I am an aquatic ecologist and oceanographer with broad interests relevant to basic and applied issues in coastal marine systems, estuaries, rivers and lakes. Much of my research has focused on studying the growth and physiology of planktonic microorganisms (planktonic algae, protist microzooplankton, invertebrate zooplankton, and bacteria). I use a holistic perspective that encompasses how planktonic organisms interact with their physical/chemical environment, how they interact with their competitors and predators, and the implications for their population dynamics.

Planktonic organisms form the base of most aquatic food webs, and thus, the processes that regulate their populations also directly affect the abundance, diversity, and activities of higher trophic-level organisms. Plankton also play critical roles in aquatic biogeochemistry, such as fluxes of carbon and nitrogen. In addition, interactions within the community of planktonic organisms relate directly to applied, water-quality issues such as nutrient pollution and eutrophication, sewage pollution, harmful algal blooms, and hypoxia.

My research approach links hypothesis-driven, controlled laboratory experiments with small-scale field manipulations and field observations. Such research is inherently interdisciplinary, connecting cell biology and physiology with ecology, and physics and chemistry of the environment. I am always open to new and interesting ways to apply my expertise.


Only select publications listed below
Name Published Date
Quantifying Per-Cell Chlorophyll a in Natural Picophytoplankton Populations Using Fluorescence-Activated Cell Sorting. 2022
Sediment Resuspension and Associated Extracellular Enzyme Activities Measured ex situ: A Mechanism for Benthic-Pelagic Coupling in the Deep Gulf of Mexico. 2021
Particle association of Enterococcus sp. increases growth rates and simulated persistence in water columns of varying light attenuation and turbulent diffusivity 2020
Anthropogenic inputs from a coastal megacity are linked to greenhouse gas concentrations in the surrounding estuary 2019
Combined effects of simulated acidification and hypoxia on the harmful dinoflagellate Amphidinium carterae 2019
Melt procedure affects the photosynthetic response of sea ice algae. 2019
Patterns of sediment-associated fecal indicator bacteria in an urban estuary: benthic-pelagic coupling and implications for shoreline water quality. 2019
Overwintering of gelatinous zooplankton in the coastal Arctic Ocean. 2018
Spatial Patterns of Pharmaceuticals and Wastewater Tracers in the Hudson River Estuary. 2018
The effects of organic carbon enrichment on respiration rates, phosphatase activities, and abundance of heterotrophic bacteria and protists in organic-rich arctic and mineral-rich temperate soil samples. 2018
Challenges to managing microbial fecal pollution in coastal environments: extra-enteric ecology and microbial exchange among water, sediment and air. 2017
Conserved Transcriptional Responses to Nutrient Stress in Bloom-Forming Algae 2017
Conserved transcriptional responses to nutrient stress in bloom-forming algae. 2017
Diverse CO2-Induced Responses in Physiology and Gene Expression among Eukaryotic Phytoplankton 2017
Onshore wind speed modulates microbial aerosols along an urban waterfront. 2017
Transcriptional response of the harmful raphidophyte Heterosigma akashiwo to nitrate and phosphate limitation. 2017
Elevated surface chlorophyll associated with natural oil seeps in the Gulf of Mexico 2016
Light and nutrient effects on the settling characteristics of the sea ice diatom, Nitzschia frigida. 2015
Diatom vertical migration within land-fast Arctic sea-ice. 2014
Geographic variability in amoeboid protists and other microbial groups in the water column of the lower Hudson River Estuary. 2014
The Marine Microbial Eukaryote Transcriptome Sequencing Project (MMETSP): Illuminating the Functional Diversity of Eukaryotic Life in the Oceans through Transcriptome Sequencing 2014
Antibiotic resistant bacteria in the Hudson River Estuary linked to wet weather sewage contamination 2013
Coupling of fog and marine microbial content in the near-shore coastal environment 2012