Huge project in the Amazon: Student discovers new environmental dangers!

Huge project in the Amazon: Student discovers new environmental dangers!

In December 2024, undergraduate student Caitlyn Kelly from Constructor University took part in a significant research expedition in the Amazon River Estuary. This trip on the renowned research ship meteor took place was part of the international GEOTRACES program. The primary objective of this expedition was to investigate the role of the Amazon outflow and mangrove belts, particularly with regard to the input of nutrients and pollutants to coastal regions and the Atlantic Ocean.

The expedition was led by Professor Dr. Led by Andrea Koschinsky, it is the second of its kind in this region, following an initial research trip in 2018 and seamless cooperation with a previous project in 2021. The Amazon, which is almost 7,000 kilometers long, plays a key role as a transport route for large amounts of nutrients and trace metals such as iron, cobalt and copper. Koschinsky emphasizes that the Amazon influences bioproductivity throughout the region, especially during periods of heavy rain, which also extend to the Caribbean and the open Atlantic.

Impact of extreme weather events

The expedition took place at the end of a period of extreme drought, which experts refer to as a “huge ecological extreme situation”. Deforestation, gold mining using mercury and the construction of dams place significant strain on the delicate ecosystems of the river and its estuary. Analysis of the mangrove belt revealed higher salinity, indicating a greatly reduced freshwater supply. The long-term consequences of this deficiency on the ecosystem are currently uncertain.

The expedition's scientists took samples at different water depths to measure the distribution of trace metals. In her bachelor's thesis, Kelly herself examined copper-binding organic molecules in the samples collected. Their preliminary analyzes reveal differences compared to the 2018 data, which is attributed to the low freshwater inflow. Koschinsky expressed concerns that human activities could significantly influence the results of their research.

Technical details of the meteor and evaluation of the samples

The research ship meteor has been in operation since 1986 and acts as an interdisciplinary platform for scientists in areas such as marine chemistry, zoology and geology. With a length of 98 meters and a maximum cruising speed of 11.5 knots, the ship can sail for up to 50 days at a time and accommodates up to 28 scientific staff. The research trip required a lead time of two years for the application, which underlines the planning of such extensive projects.

The collected samples have currently arrived in Bremen, but the evaluation will still take time. Another aspect of the expedition is the focus on understanding human impacts on the material cycles in the ocean, particularly through dam construction, deforestation and intensive agriculture. These challenges require targeted scientific consideration in order to develop possible solutions to minimize harmful influences.

The collaboration between the institutions, including the University of Oldenburg and the GEOMAR-Helmholtz Center for Ocean Research Kiel, underlines the national and international importance of such research projects. Together with four Brazilian partner organizations, the scientists are striving to gain a better understanding of the complex metabolic processes in the oceans and to shed light on the effects of climate change on sensitive marine ecosystems.