Paleolimnology is a field of study which aims to understand the long-term environmental changes which have taken place in aquatic ecosystems. The term aquatic ecosystem in this context represents freshwater bodies. Typically paleolimnological studies examine freshwater ecosystems, usually lakes.
Sediment cores are utilized in paleolimnological studies because they contain a rich history about the environment and are consistently available since sediment particles accumulate continuously overtime. Through the use of radio-isotopic dating, usually with carbon or lead, sediment cores can be dated. To uncover past environmental conditions, paleolimnologists analyze the biological, chemical and/or physical properties of these sediments.
- Biological Properties: Biological indicators which can be examined include diatoms, cysts and fossil invertebrates. By studying the biological indicators present in the different layers of sediment, scientists can infer what the environmental conditions were like at different points in time during the past. For example, different species of diatoms are accustomed to particular lake conditions, such as alkaline or acidic waters.
- Chemical Properties: This includes studying characteristics such as pH levels, the levels of dissolved oxygen and the levels of other contaminants.
- Physical Properties: Physical characteristics which can be studied include the rate of sedimentation or the texture and grain size of sediment particles.
Paleolimnology is particularly useful for studying past events and tracking global trends in climate and environmental variation. Some environmental issues which have utilized paleolimnological techniques include studying lake acidification, eutrophication, pollution, and the travel of airborne particles from the Oil Sands in Alberta.
When attempting to solve an environmental problem, it is rather helpful to understand why the problem began initially. Through the use of paleolimnological techniques, that information can be uncovered. Hopefully, by understanding the world's past environments and how they have changed, we can better protect the globe’s diversity of environments for the future.
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