Did you know that some people dedicate their entire life to studying water? Water is an incredible substance, and there are so many unique types of it. Now, I am not just talking about sparkling vs tap water. Limnology is one specific branch of water studies. Particularly, it is focused on fresh water in inland waters (lakes, rivers, streams, groundwater, wetlands, etc). Limnology has Greek and Latin roots. The Greek word limne means marsh while the Latin word limnaea describes things relating to a marsh. Limnologists are scientists that specialize in limnology and focus on studying the relationships between organisms in these inland waters and traits of their environments (including physical, chemical, biotic, etc.). This study is unique from other fields of water study because it is focused on freshwater sources and organisms. This is important because freshwater areas are smaller than oceans, so smaller events have larger consequences on them. Think about it like this - dumping a truck of fertilizer will have a much more damaging effect on a small lake than in an ocean because oceans are much larger and the fertilizer would be able to disperse more appropriately. In a lake, this could even lead to eutrophication which occurs when there are excessive amounts of nutrients in the water.

The “father of limnology” was a Swiss physician named François-Alphonse Forel. He grew up near Lake Geneva, and his father would often take him to the lake to search for artifacts from ancient times. After going to Germany for college, he returned home and became a professor of anatomy, histology, and physiology at a local university. Later, however, he began focusing on studying lakes in many different fields including physics, chemistry, biology, history, economics, and much more. In 1892, he categorized his studies as limnology, which he defined as the oceanography of lakes. His work was incredible in unifying these different subjects for the common goal of learning about water, and he also drew connections between society and small bodies of water. Forel marked humans as incredibly important to the ecosystem involving lakes because of the human need for the services provided by the lake, despite their actions that often bring it harm. Forel’s most well-known works were on underwater light, water color, lake stratification (temperatures in different depths of the lake), the zoobenthos (aquatic life) of lakes, and the value of the carbon cycle to the lake ecosystem.

The aspects of limnology first studied by Forel are still studied across the world due to their importance in determining water quality. Water quality is usually measured based on nutrient concentration, water clarity (Secchi disk), amounts of cyanobacteria, and types of zooplankton - all of which Forel studied to some extent. A chart called the Trophic State Index is made of three categories: Oligotrophic, Mesotrophic, and Eutrophic. Lakes can be put into these categories based on their phosphorus and nitrogen concentrations, water clarity, and chlorophyll A concentration. When a lake is Oligotrophic, its nutrient concentrations are extremely low, so plants have difficulty growing. On the other hand, Eutrophic lakes have extremely high nutrient concentrations, so plants tend to grow excessively there. Mesotrophic lakes have the most desirable nutrient concentration and are more even.

Limnology is one of the most unique and unknown fields of science! It is incredibly important to our planet, our way of life, and our knowledge of the water we drink every day! Check out the next article, “Hydrology...Oceanography...Limnology...Glaciology! Oh, too many to count! - More on Limnology” to explore limnology deeper.