Adam J. Heathcote, Director, Department of Water and Climate Change

Ph.D., Iowa State University, (Ecology and Evolutionary Biology), 2013
B.Sc., Iowa State University, (Animal Ecology), 2005 

Phone: (651) 433-5953 ext. 24

Research Interests 

I am an ecosystem ecologist with an emphasis on the interactions between lake biogeochemistry and plankton ecology. My research involves quantifying how humans impact the cycling of nutrients (carbon, nitrogen, and phosphorus) in lakes and how these changes are reflected in terms of lake productivity and algal community structure. To answer these questions, my work combines neo- and paleolimnological methods to quantify changes across both space and time.

Eutrophication and Shallow Lakes

One major aspect of my research is estimating the impact of anthropogenic eutrophication on the ecosystem functioning of shallow prairie lakes. Anthropogenic eutrophication is the degradation of water quality due to human-induced nutrient pollution and is one of the greatest threats to freshwater resources worldwide. My work reconstructs the history of eutrophication through time using biological (sub-fossil algae) and geochemical indicators (organic matter, erosional deposits) preserved in lake sediments. This provides a background reference condition for lakes prior to European settlement and allows for the correlation of eutrophication to historical landscape and land-use changes.

In addition to paleolimnological approaches, my work also involves research on contemporary effects of eutrophication on plankton ecology in lakes. As eutrophication of lakes intensifies, the prevalence of harmful algal blooms in lakes has become increasingly common. These blooms, often the result of toxic species of Cyanobacteria (blue-green algae), can fundamentally alter the function of lakes in numerous ways leading to the collapse of food webs, hypoxia, and the production of toxins that are harmful to humans, pets, and livestock. My work specifically looks at how Cyanobacteria escape mechanisms of top-down control and better exploit nutrient resources in eutrophic lakes, which leads to conditions that favor bloom formation.

Carbon Sequestration in Boreal Lakes

The second major aspect of my research involves working in collaboration with scientists in Quebec (Canada) on several projects quantifying carbon sequestration (burial) in freshwater lakes. Despite their relatively small area on Earth, lakes play a significant role in the global carbon cycle, burying up to four times as much carbon as the world's oceans on an annual scale. Additionally, the boreal forest has the highest density of surface waters on the planet , holding over a quarter of the world's lakes. My work involves using lake sediments to quantify the stock of carbon buried in lake sediments since the last glaciation (ca. 8-13,000 years ago) as well as changes in carbon sequestration over time. Though boreal lakes are often considered relatively pristine due their remote location, there is increasing evidence that these systems may be impacted by global ecosystem changes to climate and atmospheric deposition of nutrients. My work involves re-examining the rates of carbon sequestration in lakes over the last century and how they may have changed as humans alter global atmospheric and climatic processes.

Representative Publications

Diamond SE, Harvey R, Heathcote AJ, Lini A, Morales-Williams A. 2022. Decoupling of chemical and biological recovery from acidification in a montane lake, Vermont, USA. Journal of Paleolimnology (in press). 

Ramstack Hobbs JM, Heathcote AJ, VanderMeulen DD, Edlund MB. 2022. Integrating water quality monitoring and diatom community trends to determine landscape-level change in protected lakes. Ecosphere 13 (8): e4199. 

Delaney C, Li X, Holmberg K, Wilson B, Heathcote AJ, Nieber J. 2022. Estimating lake water volume with regression and machine learning methods. Frontiers in Water 4: 886964.

Edlund MB, Ramstack Hobbs JM, Heathcote AJ, Engstrom DR, Saros JE, Strock KE, Hobbs WO, Andresen NA, VaderMeulen D. 2022. Physical characteristics of northern forested lakes predict sensitivity to climate change. Hydrobiologia 849: 2705-2729.   

Sauer HM, Hamilton TL, Anderson RE, Umbanhowar Jr. CE, Heathcote AJ. 2022. Diversity and distribution of sediment bacteria across an ecological and trophic gradient. PLOS ONE 17 (3): e0258079.

Wang M, Bao K, Heathcote AJ, Zhu Q, Cheng G, Li S, Zhang C. 2021. Spatio-temporal pattern of metal contamination in Chinese lakes since 1850. Catena 196: 104918.

Anderson NJ, Engstrom DR, Leavitt PR, Flood S, Heathcote AJ. 2020. Changes in coupled carbon-nitrogen dynamics in a tundra ecosystem predate recent regional warming. Nature Communications Earth & Environment 1: 38.

Anderson NJ, Heathcote AJ, Engstrom DR, GLOBOCARB Data Contributors. 2020. Anthropogenic alteration of nutrient supply increases the global freshwater carbon sink. Science Advances 6 (16): eaaw2145.

Lapierre J, Heathcote AJ, Maisonneuve P, Filstrup CT. 2019. Is limnology becoming increasingly abiotic, riverine, and global?. Limnology and Oceanography Letters 5 (2): 204-211.

Saros JE, Anderson NJ, Juggins S, McGowan S, Yde JC, Telling J, Bullard JE, Yallop ML, Heathcote AJ, Burpee BT, Fowler RA, Barry CD, Northington RM, Osburn CL, Pla-Rabes S, Mernild SH, Whiteford EJ, Andrews MG, Kerby JT, Post E. 2019. Arctic climate shifts drive rapid ecosystem responses across the West Greenland landscape. Environmental Research Letters 14 (7): 074027.

Edlund MB, Schottler SP, Reavie ED, Engstrom DR, Baratono NG, Leavitt PR, Heathcote AJ, Wilson B, Paterson AM. 2017. Historical phosphorus dynamics in Lake of the Woods (USA-Canada) – does legacy phosphorus still affect the southern basin?. Lake and Reservoir Management 33 (4): 386-402.

Cael BB, Heathcote AJ, Seekell DA. 2017. The volume and mean depth of Earth’s lakes. Geophysical Research Letters 44 (1): 209-218.

Heathcote AJ, Filstrup CT, Kendall D, and Downing JA. 2016. Biomass pyramids in lake plankton: influence of Cyanobacteria size and abundance. Inland Waters 6 (2): 250-257.

Filstrup CT, Heathcote AJ, Kendall DL, and Downing JA. 2016. Phytoplankton taxonomic compositional shifts across nutrient and light gradients in temperate lakes. Inland Waters 6 (2): 234-249.

Heathcote AJ, Anderson NJ, Prairie YT, del Giorgio PA. 2015. Large increases in carbon burial in northern lakes during the Anthropocene. Nature Communications 6: 10016.

Heathcote AJ, del Giorgio PA, Prairie YT. 2015. Predicting bathymetric features of lakes from the topography of their surrounding landscape. Canadian Journal of Fisheries and Aquatic Sciences 72 (5): 643-650.

Heathcote AJ, Ramstack Hobbs JM, Anderson NJ, Frings P, Engstrom DR, Downing JA. 2014. Diatom floristic change and lake paleoproduction as evidence of recent eutrophication in shallow lakes of the midwestern USA. Journal of Paleolimnology 53: 17-34.

Reavie ED, Heathcote AJ, Chraïbi VLS. 2014. Laurentian Great Lakes phytoplankton and their water quality characteristics, including a diatom-based model for paleoreconstruction of phosphorus. PLOS ONE 9: e104705.

Filstrup CT, Heathcote AJ, Downing JA. 2014. Sediment accumulation rates still increasing in Iowa's natural lakes. In McDonough D.C. (ed.) "Getting Into Soil and Water: 2014". Iowa Water Center, Ames, IA. p. 14-16.

Filstrup CT, Hillebrand H, Heathcote AJ, Harpole WS, Downing JA. 2014. Cyanobacteria dominance influences resource use efficiency and community turnover in phytoplankton and zooplankton communities. Ecology Letters 17: 464-474.

Juggins S, Anderson NJ, Ramstack Hobbs JM, Heathcote AJ. 2013. Reconstructing epilimnetic total phosphorus using diatoms: statistical and ecological constraints. Journal of Paleolimnology 49: 373-390.

Heathcote AJ, Filstrup CT, Downing JA. 2013. Watershed sediment losses to lakes accelerating despite agricultural soil conservation efforts. 2013. PLOS ONE 8: e53554.

Filstrup CT, Harpole WS, Heathcote AJ, Shurin J, Kondoh M. 2012. Emerging Issues Workshop Report: Causes and consequences of biodiversity loss across ecosystems. Limnology and Oceanography Bulletin 21: 98-99.

Heathcote AJ, Downing JA. 2012. Impacts of eutrophication on carbon burial in freshwater lakes in an intensively agricultural landscape. Ecosystems 15: 60-70.