Freshwater ecosystems are some of the most threatened environments on our planet. Globally, water quality has deteriorated rapidly since the 19th century, while water quantity is especially vulnerable in semi-arid regions. This has led to almost 80% of the world’s population being exposed to substantial water security threats. 

For over 20 years I have worked on assessing human and climatic impacts on some of the world’s most important freshwater ecosystems, including Lake Baikal and the Aral Sea in central Asia, and the Okavango Delta in southern Africa. Key to much of this work is the use biological organisms and stable isotopes to reconstruct past environments.