Marja Lindholm | Akateeminen Kirjakauppa

According to the doctoral thesis of geographer Marja Lindholm, aquatic vegetation in the study lakes in Tampere region is not homogenised over time, as has been observed elsewhere in the world.

Global change threatens the vegetation of lakes. This is alarming as aquatic plants are vital to the well-being of lakes. In the doctoral thesis carried out at the University of Oulu, spatial and temporal changes in the aquatic plants of small lakes during the last 70 years were investigated. The changes were studied by using vegetation surveys carried out in four different decades in lakes near the city of Tampere and by surveying the same lakes again in summer 2017.

The results of the doctoral thesis show that environmental changes through decades, such as declining of agriculture, are related to functional diversity of aquatic plant communities to some extent. Functional diversity was studied through functional traits of species, such as size and growth form. According to Lindholm, the functional role of aquatic plants would be important to take into account in protection and restoration of lakes.

Lindholm's doctoral thesis shows how important long-term monitoring is in biodiversity research. Therefore, there is a need to continue ongoing monitoring programs and conduct more re-surveys of historical data, to be able to estimates the impacts of human activities on temporal variation of biodiversity.