Energy shortages in the early 20th century led to a survey of peatlands in Sweden. A recent study looked at peatlands near Uppsala to see if historical data could show changes in peat and plants over the past 90 years. The surveys suggested that the peatlands have become drier and richer in nutrients. The peat has also become thinner, likely due to changes in water levels from draining wetlands. While the study couldn't compare specific areas within the peatlands, it did show overall changes over time. This research indicates that peatlands in Sweden have changed since the early 20th century.