The word Limnology comes from two Greek words. Greek ‘Limnos’ means lake or submerged body of water and Greek ‘Logos; means knowledge. Therefore, the search for knowledge on the lake is the main topic of limnology. From the origin of this branch to the present day, various scientists have defined limnology in different ways.
Below are some definitions:
Limnology is a branch of science that deals with the study of the biological, physical, chemical, geological, biological, aquatic, and aquatic ecosystems (freshwater or saltwater, natural or artificial), especially of lakes, reservoirs, ponds, rivers, wetlands, and groundwater, ecological and hydrological aspects.
In a broad sense, limnology is the science of research /discussion on all aspects of all types of aquatic ecosystems and biology (Brezonik, 1996; Wetzel, 2003).
Limnology is a relatively new science. In the modern definition, limnology is considered to be synonymous with freshwater biology. According to Wetzel (2003), in the broadest sense, limnology is the acquisition of knowledge about the functional relationship between freshwater organisms and their productivity, which is affected by the movement of various physicochemical and biological regulators in the environment.
Limonology is the scientific study of the world’s inland water bodies such as lakes, artificial reservoirs, rivers, ponds, wetlands, saline lakes, and coastal bays and wetlands.
According to F A Forell (1892), the theory of the ocean of lakes is called limnology. Lind (1989) defined the limnology as marine aquatic ecology, is called limnology. According to Margallef (1983), the ecology of non-marine water is called limnology.
Baldy (Idhasfar, 1949) defined limnology. According to him, limnology is the scientific discussion of the process and conversion of energy and matter in a lake.
According to Welch (1952), Limnology is that branch of science which deals with biological productivity of inland waters and with all the causal influences which determine it.
This definition includes biological productivity, quality and quantitative characteristics, and its actual and potential aspects of limnology. Inland water refers to all types of groundwater, such as flowing or stagnant, salty or other physical, chemical elements. Various regulators such as physical and chemical, biological, climatic influences that determine the nature and extent of biological production. Due to the different inland water bodies, the quality and quantity of the organisms vary.
According to Hutchinson (Hutchinson, 1957), limnology is the study of the interconnected geological, physical, and biological activities in a lake collectively.
According to Odum (Odum, 1971), Limonology discusses various aspects of freshwater, such as physical, chemical, and biological aspects.
According to Professor Nurul Islam (1993), the subject that deals with the biology and composition of aquaculture is called limnology.
Limnology is basically a synthetic science. Limnology provides solutions to various problems of biological nature through the proper application and coordination of certain facts, basic principles, chemistry, physics, geology, hydrology, meteorology, and other sciences. It is basically an ecological issue.
Historically, the term limnology has been associated with lakes, and the term rheology has been applied to the science of flowing water. Currently, the term rheology has been dropped from the term limnological. The term rheology is an established name for a completely different branch. In this branch, research is done on water flow and water-soluble components like oil, pigment, etc.
Limnology and oceanography discuss similar problems and processes. Oceans, lakes, and rivers have some properties as a liquid medium. However, the sea is wider in size and older than the inland water. The spread of inland water bodies is inconsistent and relatively polymorphic (based on geological time) and is irregularly spread throughout the continental interior. As a result of this continuity of the sea, a wide range of plant and animal species exist.
Depending on the more diverse processes of inland water colonization, the diversity and expansion of plants and animals become more limited and diminished. In addition, seawater, especially ocean water, contains 35-39 grams of salt per liter of water, the main ingredient of which is sodium chloride (Nacl). Inland freshwater, on the other hand, contains at least 0.01 g of salt per liter of water. The composition of the salt varies significantly in the water.
In many cases, inland saltwater lakes have a higher salt-to-salt ratio than seawater. Such an ecosystem is of an unusual type and thus becomes the focus of its limnological study. In the case of flowing reservoirs, the chemical processes and techniques of inland reservoirs depend in no small extent on the geochemical condition of the soil. Aquatic ecosystems interact with flowing reservoirs of various subsystems and elements.
The extent and definition of any science cannot be determined without considering the history of its evolution and the subject matter, institutions, and development groups discussed. Knowledge of some of the major theories and theoretical concepts can be gained through historical discussions. Elster (1964) and Uno (196) describe the early history of limnology. Talling (2005) recently added these ideas.
Aquatic life attracted scientists and naturalists in the 18th, 18th, and 19th centuries, including Leeuwenhock, Muller, Schaffers, Trembley, Eichhorn, Bonner, and George. They have seen in research work. These research activities shed light on aquatic organisms and their behavior and their reproduction in water.
The discovery and initial discussion of marine plankton by Muller in 1845 aroused interest in studying freshwater organisms, especially lake plankton. Duviller describes and measures internal waves. J. Leslie (J. Leslie, 1838) was the first to examine the thermal structure of deep lakes, the action of air, and the penetration of light, which served as important milestones in advancing limnology (Goldman and Horne, 1983). Moreover, Morren and Morren (Morren and Morren, 1841) focus on increasing and decreasing the activity of daily photosynthesis. Junge and Forbes were the first to call the lake a microcosm. In particular, the research paper entitled “Lakes” refers to lakes as microcosms and describes the interrelationships between the fundamental forces of life and organisms (Forbes, 18).
The results of Forbes’ research make a significant contribution to limnology. However, the F.A. Farrell’s (F.A. Forel, 1901) research work is the first book on limnology. Liman researched the biology, physics, and chemistry of lake through his extensive monograms on lakes. The development of limnology as an organized science continued to grow towards the end of the nineteenth century. In the early twentieth century, many limnological field stations and laboratories were established near the lake. For example, the Auto Zacharias Limnological Research Institute, Germany, was established in 1901 in Plon. To this day, it has been playing an important role. It is currently called the Macro-Plank Institute, which researches evolutionary biology.
The subsequent development of limnology began in the early twentieth century. During this time, the research work of Thienemann (Thienemann, 1882-1960) and Naumann (1891-1934) in Germany made essential contributions to limnology. They conducted the first comparative research on the continent of Europe, conducting research independently. Notable among these research works are mainly classification, regional characteristics, and descriptions of biogeochemical cycles.
Using Weber’s theory (1906), these studies provide insights into oligotrophic and eutrophic systems that have served as essential foundations for developing lymphology. The classification of lakes based on nutrients was the first step in the development of lymphology. Birge and Juday (1911) provide an idea of the types of lakes. In this case, they consider the productivity of lake organic matter, the depth of the lake, the morphology of the lake, and the interrelationship between dissolved oxygen.
L. Agassiz (1850) was a pioneer in the development of limnology in North America. Birge (1851-1950) and Jude (182-1944) studied the effects of heat and chemical stratification on plankton. They did comparative research on lakes in North America. They established graphic relationships with quantitative studies such as water transparency, organic matter, and phosphorus, with frequency distribution and trends (Juday and Birge, 1933). Moreover, they did a comparative study of some lakes in Central America.
There are important differences between the early stages of the development of limnology in Europe and America. American researchers studied the chemical cycles of the system and European researchers studied the biological community (Margalef, 1983). For example, Birge and Juday use the amplitude and concentration of dissolved oxygen to express certain factors acting on the lake.
The important events in the development of lymphology are as follows:
Thienemann and Naumann founded the International Association of Theoretical and Applied Limnology in 1926, now known as the International Society of Limnology.
A laboratory was established in Wildermeier in 1931 to support the Freshwater Biological Association, founded in 1926. The institute conducts essential research from the northern Lake Districts of England (Talling, 1919).
Yoshimara’s (1937) research work in Japan established an important scientific database. Many Japanese limnologists also play an important role in oceanography as important scientific research. Japan is the only country that demarcates the boundaries between limnology and oceanography. They conducted research on the eutrophication of inland and coastal waters. This is an important aspect of aquaculture. They need to understand the significant limnological oceanographic processes in aquaculture and even have a comparative idea to apply the same technique to freshwater and saltwater ponds for food.
In the United States and Europe, laboratories have been established near lakes and regional systems, which have helped build internationally renowned institutions. These laboratories existed as active centers that conducted research on local aquatic ecosystems and collected scientific data. These studies have played an important role in highlighting the evolution of various theories and sciences of limnology and regional systems.
Extensive research by various groups has resulted in tropical limnology from temperate regions. Thenemann’s research shows that Java, Sumatra, and Bali lakes lack hypoallergenic oxygen, so the traditional oligotrophic / eutrophic classification cannot be used for temperate lakes.
The classification described by Thinemann and Naumann had a catalytic effect on the scientific progress of limnology (until 1958).
In 1950, the classification of lakes became a fundamental factor. Thinemann (1925) added another word, dystrophy, to the terms eutrophic and oligotrophic, meaning a lake rich in high-density humic material. Central and South American, North American, and European influences are not the same. In South America, researchers from the Max Planck Institute (Sioli, 1975) and the National Institute for Amazonian Researchers (INPA) conducted a wide range of research on significant rivers and deltas. Bonito (1985.1986), and others, Uruguay, studied the Bermejo River
Comparative tropical limnology has been developed in Africa based on various explorations on deep and shallow lakes (Bidley, 1981). Tropical limnology has played a significant role in research on African lakes such as Lake Victoria (Tolling, 1985, 198) and other lakes (Tolling, 1989). Tolling and Limoli presented a more relevant summary of tropical limnology in 1997.
The International Biological Program (IBP) conducted extensive research on the moon (Carmok Ze et al. 1983) and Lake George (Ganf, 1974; Viner, 1975, 1977). Due to the comparative study between lakes of different latitudes and the normalization of the method and the quantitative measurement of the process, IBP was important for limnology. It establishes more dynamic and comparative ideas, mostly through research on ecological processes. It provides a scientific basis for more quantitative ideas in lake research.
The evolution of limnology continues to be influenced by the construction of drainage dams in South America and Africa (Vander Heide, 1982). In Spain, 100 reservoirs were studied, which opened the door to reservoir types theory and classification process (Margalif, 1985, 198). In this case, mainly research on artificial aquifers reveals the processes that take place in them. Margalif’s study provides an essential theoretical, and practical perspective on limnology.
Extensive research over the last 30 years has led to the emergence of various theories in limnology. In the twentieth century, Hutchinson (1958, 198, 1985, 1993) conducted significant research in limnology and trained new researchers. Notable researchers who give donations to research works include Whipple, Fair and Whipple (1927), Welch (1935,1948), Ruttner (1954), Dussart (1966), Hynes (1972), Golterman (1975), Wetzel (1975), and Margalif (1983). 1991 and 1994), Goldman and Horne (1994), Kalff (2002), and Carpenter (2003).
Significant scientific advances have been made in limnology in the twentieth century. Knowledge of limnology in the case of lakes, reservoirs, rivers, and wetlands has expanded considerably in the early 1970s due to the works of Thinemann and Naumann.
The following are the processes of lymphological development:
Phytoplankton succession and the processes influence this process, a spatial and temporal succession of phytoplankton (Harris, 1970,1984,1986; Reynolds, 1994,1995, 1996,1997; Bo Ping Han et al., 1999).
Energy transfer, phyto-zooplankton integration techniques and the structure and composition of food webs (Porter, 1973; Lampert and Wolf 1986).
Sediment, sediment and water interaction, water-geochemical and geochemical research of lake chemical processes (Srumm and Morgan, 1981).
Gain extensive knowledge of species proliferation, biodiversity, biodiversity, and controlling factors (Lamotte and Boulieve, 1983).
Climate and hydrology in different aspects of geography and their effects on early production and the widespread scientific spread of biogeochemical cycles (Straikraba, 1973; Le Cren and Lowc-McConnel, 1980; Talling and Lemoalle, 1998).
Table Showing Evolution of Limnology:
|
Year |
Researchers |
Research Works |
|---|---|---|
|
1901 |
F.A. Forel |
The physical classification of lakes based on thermal properties; |
|
1911 |
E.A. Birge and C. Juday |
Chemical classification based on stratification and dissolved oxygen; |
|
1915 |
A. Thieneman |
Chemical classification based on stratification and dissolved oxygen; |
|
1932 |
A. Thieneman and E. Ruttner |
Sunda Expedition in Indonesia; |
|
1938 |
S. Yohimora |
Vertical arrangement of oxygen and temperature of lakes in Japan, comparative analysis; |
|
1941 |
C.H. Hortimar |
Bottom-water interaction. Circulation of the lake ; |
|
R. Linderman |
R. Linderman |
Application of dynamic trophic formulas to lakes, concepts of lake identification in functional systems; |
|
1952 |
E. Steemann Nielsen |
Developing techniques for measuring early productivity using radioactive isotopes; |
|
1956 |
E. P. Odum |
Development of metabolic measurement systems in rivers; |
|
1956 |
G.E. Hutchinson and H. Loffler |
Lake thermal classification; |
|
1958 |
R. Margalef |
Revealing information about the process of phytoplankton evolution through theory; |
|
1964 |
IBP (International Biological Programme) |
Establishment of International Biological Program; |
|
1968 |
R.A. Vollenweider |
Expression of sedimentation from reservoirs and its effect on eutrophication of lakes; |
|
1974 |
C.H. Mortimer |
Research on lake water dynamics; |
|
1974 |
J. Overbeck |
Inventions of aquatic and biochemical microbiology; |
|
1990 |
R.G. Wetzel |
Research on the interaction of the littoral system and pelagic zone of the lake; |
|
1997 |
C.S. Reynolds |
Summary of the positional and temporal position of phytoplanktonic cycles; |
|
2004 |
Goldman, Sakamoto and Kumagai |
Research on the effects of lakes and reservoirs on changes in the earth; |
Over the past few decades, several studies have been conducted on fisheries expansion, population dynamics, biogeography and chemical elements, trophic levels, especially lake morphometry, and the structure of artificial reservoirs and ichthyofauna (Barthem and Goulding, 1997). Such research has been playing a role in the formation of various ideas in theoretical ecology and its application. At the ecosystem level, river hydrology, interaction with floodplains and lakes (Neiff, 1996; Junk, 1997), wetland control techniques (Mitsch, 1996), comparative study of reservoirs (Margalef et al. 1976;
Stralkraba et al. 1996), saline lakes ( Williums, 1996), the interaction between terrestrial systems and aquatic systems (Decamps, 1996), and research on the ecology of large and small rivers (Bonetto, 1994; Walker, 1995) has led to significant advances in limnology.
Extensive knowledge has been acquired about various process management techniques at the interaction or ecosystem level between system components, making important contributions to lake and reservoir management. The remarkable work of Henderson and Sellers (1994) and Cooke et al. (1996) has been doing instrumental in modeling aquatic environmental management.
Some Internationally Important Limnological Publications
- Advances in Limnology
- Annales de Limnologie – International Journal of Limnology
- Aquatic Conservation
- Aquatic Ecology
- Canadian Journal of Fisheries and Aquatic Sciences
- Chinese Journal of Oceanology and Limnology
- Freshwater Biology
- Hydrobiologia
- Journal of Ecology and Fisheries
- Journal of Limnology
- Limnetica
- Limnologica
- Limnological Review
- Journal of the North American Benthological Society
- Limnology and Oceanography
- Marine and Freshwater Research
- New Zealand Journal of Marine and Freshwater Research
- Review of Hydrobiology
- River Research and Applications
- Journal of Coastal Research
- Journal of Ecology
- Journal of Fish Biology
- Journal of Freshwater Biology
- Journal of Great Lakes Research
- Journal of Lake and Reservior Management
- Journal of Phycology (US)
- Journal of Plankton Ecology
- Journal of Plankton Research
- Journal of Tropical Ecology
- Lake &Reservior Research and Management
- International Journal of Ecology and Environmental Sciences
- International Review of Hydrobiology
- Aquaculture
- Aquatic Botany
- Aquatic Ecology
- Biodiversity and Conservation
- Ecology
- Ecology of Freshwater Fish
- Environmental Biology of Fishes
- Fisheries Management and Ecology
- Fisheries Research
- Freshwater Riview
- Freshwater Biology
21st Century Limnology
The last decade of the twentieth century has seen conceptual advances in limnology and the discovery of various scientific processes. The importance of these discoveries in indoor aquatic system management, revitalization programs has increased. Basic science supports such an application.
This decade has seen significant changes in technology and the invention of more accurate methods, mostly automated measurement methods and real-time data collection. An analysis of the progress of limnology can lead to a conclusion. The significant developments at this time are as follows:
- From the knowledge of the processes, it can be deduced that the lake is not an inland internal body of water of the continent but depends on the interaction of the bottom of the body of water.
- The response of the lake to human activity in the reservoir depends on the type of lake activity, lake formation, or morphology.
- As a result of human activity in the vicinity of the extractable reservoir, the reaction of the lake and the change in the remote area of the basin are different.
- Collection of information on the physical and chemical processes that occur in the lake in response to communities brings about lake productivity, biodiversity formation, and genetic changes (Kajak and Hillbrichr-IIKowska, 192; Reynolds, 1997a; Talling and Lemoalle, 1998).
Importance of Limonology As A Science
Like other sciences, the study of limnology is essentially a search for principles. Principles that involve several processes and management strategies that are used to make decisions and compare.
Particularly, emphasis should be placed on the comparative aspect of limnology. For example, comparing the hydrology of rivers, lakes, and reservoirs on the fundamental functional aspects shows that there are some fundamental practical aspects that influence the life cycle of aquatic organisms and their extent and biomass.
Other important factors are the physiological study of phytoplankton and the analysis of the response to changes in light intensity due to currents. This new approach sheds light on hydrodynamics and its effects on the vertical structure as a major controlling factor in the system`s phytoplanktonic sequence. This approach has opened wide theoretical and practical doors in limnology research. A notable aspect of this approach is that it is closely related to recent limসology, conceptually similar to oceanography.
Limonology is considered a science because of its ability to make predictions, and it is vital in applied limnology. In recent years, deforestation and air pollution around various types of waste reservoirs have resulted in acid rain, leading to a gradual deterioration of inland water bodies. All these processes which are damaging the inland water bodies can be brought back to normal by changing and correcting them. On the other hand, human intervention in aquatic organisms (over-exploitation of aquatic plants and animals, the introduction of exotic species) has brought about many structural changes in the aquatic ecosystem. In addition to pollution problems, inland water bodies are affected by eutrophication.
Proper management is required for better utilization of existing resources in lakes, rivers, and reservoirs. In many countries, the construction of landscaping dams has resulted in significant changes in natural aquatic and terrestrial ecosystems, creating new ecosystems with unique features. These ecosystems can be managed for a variety of purposes with little investment through the application of basic knowledge. It can also perform important practical functions in limnology by increasing scientific interest and basic knowledge.
Another important aspect of distinguishing between basic and applied limnology is the study of the evolution of lakes and artificial reservoirs.
The ecosystem can be identified by the scientific information obtained by comparing different lakes and reservoirs from the point of view of origin.
Aquatic ecosystems form complex systems of interaction with terrestrial systems.