Peatlands were studied to understand how geochemistry and pollen analysis can reveal environmental changes over the past 11,600 years. By looking at different types of peatlands and environments, researchers found that climate and human activities have influenced soil erosion, forest evolution, and atmospheric metal pollution. They also discovered how past climate changes affected peat decomposition, vegetation, and human activity, especially during the Little Ice Age. Combining geochemistry and palynology provided a more complete picture of past environmental changes, helping us understand how ecosystems have evolved and functioned over time.