dr. M.R. (Maarten) Van Hardenbroek van Ammerstol

Currently working on the TRICMA² project (PI Chris Smit).

In my research I aim to understand the processes that cause environmental change – both natural and anthropogenic. I do this by studying invertebrates and geochemistry of salt marshes and lakes. I also look at lake sediment records, which contain evidence of environmental change happening over long time periods. Some of my work involves monitoring modern systems, other projects study trends and events in the past 15,000 years. You can find an overview of my research interest and projects below. My study sites include salt marshes of the Wadden Sea, and lakes in the Arctic and boreal zone of (Alaska, Fennoscandia and Siberia) and temperate lakes across Europe.

Effects of biodiversity loss, climate change and pollution on salt marshes & pathways to their sutainable management

The salt marshes of the Wadden Sea are among the last untouched ecosystems in northwestern Europe. They are not only indispensable feeding grounds for millions of birds but also have an important role in coastal protection. Due to biodiversity loss and pollution on the salt marshes and climate change, there is an urgent need for action perspectives to safeguard this exceptionally valuable nature for the future. Link to current TRICMA² project.

Greenhouse gas emissions from lakes – past and present

Lakes and wetlands are the largest natural source of methane, a potent greenhouse gas. It is still not very well known which processes control these methane emissions. I pioneered the use of stable carbon isotopes of invertebrate remains as a tracer for past methane availability in lakes. My work also includes monitoring greenhouse gas emissions from modern lakes.

Aquatic food web structure under stress

Pollution, eutrophication, and fisheries put severe stresses on lake ecosystems. Aquatic food webs can respond to these stressors gradually, but in many lakes the change is rapid and catastrophic once a threshold is passed. I combine two approaches using sedimentary remains: stable isotopes and network analysis.

Taxon-specific stable isotope analysis

I'm very interested in developing the use of stable isotopes (H, C, N, O) measured on sedimentary remains of organisms. Stable isotopes can provide detailed information about energy sources, food web structure, and habitat as well as insights into climate and hydrological processes. I use remains of chironomids (non-biting midges), cladocerans (water fleas), Coleoptera (beetles), bryozoans (moss animals), and many other groups as well as fish scales and other remains.

Environmental impact of prehistoric settlements

I am fascinated by prehistoric lake settlements because of their superb preservation in waterlogged conditions. Using sedaDNA methodology I investigate how such lake-side settlements impacted on their environment. Information from geochemistry, sedaDNA, and biological remains creates a complete picture of how our ancestors interacted with their environment.