HYDROBIOLOGY: FIELD OF STUDY AND RESEARCH EXAMPLES - BIOLOGY - 2025

The Hydrobiology is the science that as part of biology, is responsible for the study of living things that inhabit the water bodies. It is linked to two branches of research, depending on the degree of salinity of the aquatic environment in which the species develop.

Fresh (continental) waters, so called because they have very low concentrations of salts, are the object of research in limnology. As for salty (marine) waters that are characterized by very high concentrations of salts, they are addressed by oceanography.

Both fresh and salty waters are part of extensive geographic areas with well-defined characteristics, which make them easily identifiable, known as ecosystems.

Each of these ecosystems consists of two components that interrelate with each other, creating a synergistic environment that works as a whole, in perfect balance.

Such components are: the biotic factor that corresponds to everything that has life within the ecosystem and the abiotic factor that is related to the inert or lifeless elements, but essential for its development.

Now, in aquatic ecosystems, communities of plants and animals develop, such as: phytoplankton, zooplankton, benthos and nekton.

Hydrobiology is dedicated to the scientific observation of this particular biotic factor, on an individual and group scale, to understand its dynamics in general. Among the aspects involved in this dynamic are the physiology, metabolism, ethology, reproduction and development of the species.

For this reason, this science is of great value in detecting environmental impacts, locating their origin and correcting it, if necessary.

History of hydrobiology

At the end of the 19th century and the beginning of the 20th century, the sciences in charge of the study of nature enjoyed a great reputation. However, many of these were overshadowed by the appearance of more modern and complex disciplines.

The daze at the emergence of new technologies dismissed hydrobiology for its empiricist methodology based on collection and observation.

However, towards the decade of the 70's there was an awakening of human consciousness regarding the neglect of the natural environment, at the expense of such dazzling.

Then, ecology was reborn as a premise for maintaining the natural balance between the environment and living beings in interaction with it.

Interest in preserving the environment reached its peak in 1972, when the First World Meeting on the Environment was held in the city of Stockholm.

The first article of the letter resulting from that meeting reads: "Every man has the right to an adequate environment and has the duty to protect it for future generations."

As a consequence of that meeting, hydrobiology regained its relevance, since the state of degradation of water bodies began to be the greatest evidence of the gravity in which the planet was.

The historical use of water

As is historically proven, the great civilizations had their seat near fresh or salt water sources, without which the development of life was impossible.

However, the management of this resource has not been rational and its physical and energy benefits have been used indiscriminately. Will it be possible to continue doing so?

Hydrobiology as a science is able to answer this question, becoming a key piece to monitor the health of the ecosystem.

What does hydrobiology study? Object of study

One of the fields of study of hydrobiology responds to the stability of aquatic ecosystems. An ecosystem is considered stable when the variations of the characteristic values ​​of the species are kept within an average, for long periods of time.

Biomass is one of these values ​​and corresponds to the mass of living organisms in a given ecosystem, at a given time.

The fluctuation of biomass at different times of the year is an indicator of the stability of the ecosystem. Even if the environmental conditions do not stay within certain parameters, the biomass of the stock should not vary.

Similarly, hydrobiology addresses fields as varied as: aquatic toxicology and taxonomy; fish disease diagnosis, prevention and therapy; chemical communication in plankton; major nutrient cycles; molecular ecology; fish breeding and genetics; aquaculture; control and verification of the incidence of pollutants, hydrobiology of fishing and many others.

Hydrobiology departments, in many faculties, focus on the environmental impacts caused by human influences on populations of aquatic organisms and their trophic structure.

In this regard, hydrobiological resources are the renewable assets found in the oceans, seas, rivers, lakes, mangroves and other bodies of water, to be exploited by human beings.

There are marine hydrobiological resources, which are all species that develop in oceans and seas. At present, approximately 1000 species have been classified among fish, aquatic mammals, crustaceans and mollusks.

The continental hydrobiological resources correspond to the species that populate the fresh waters and the hydrobiological resources in mangroves, respond to the species of fish, mollusks, crocodiles and prawns that colonize forests developed at river mouths.

All these species are fundamental both for society, as well as for industry and the economy.

Examples of studies in hydrobiology

Within the applicability of this discipline to everyday life, many magazines and online publications can be consulted, dedicated to the dissemination of investigative content.

Such is the case of Hidrobiológica and International Review of Hydrobiology (International Review of Hydrobiology) species of catalogs of research works referring to the study of hydrobiological resources.

Prawn Gulf of Mexico

There is, for example, a 2018 investigation on the nutritional needs of native shrimp in the Gulf of Mexico area. The evolution of the species was monitored through feeding tests, with various types of diets that benefited its growth.

The result of this work contributes to the implementation of diets for the development of shrimp for industrial exploitation.

Sediment composition

Another study from 2016 exposes the composition of the sediment as a determining factor for the spatial location of shrimp in the Dead Sea lagoon system.

This system is divided into three zones: A. B and C and in each of them, the sediment arrangement is different. The location of the species will be the one that meets the optimal conditions for its development.

However, the research concluded that other hydrological factors also govern spatiality, such as the temperature and salinity of the water and the time of year.

Detritus and food webs of rivers and streams

Finally, reference is made to a study from 2015, which generates a model to explain the influence of detritus in the establishment of food webs of rivers and streams.

Organic waste (detritus) affects food chains and energy transmission from waste to absorption cycles, due to biochemical processes

The model explains the hierarchies in which decomposers are organized, according to climate, hydrology and geology.

Based on this, it is about explaining how the degrees of decomposition vary in large geographical areas and also predicting how human action affects the decomposition phases.

References

1. Alimov, AF (2017). Stability and Steadiness of the Aquatic Ecosystems. Hydrobiological Journal, 3-13.
2. Andy Villafuerte, Luis Hernández, Mario Fernández and Omar López. (2018). Contribution to the knowledge of the nutritional requirements of the native shrimp (MACROBRACHIUM acanthurus). Hydrobiological, 15-22.
3. Dejoux, C. (January 2, 1995). Hydrobiology: a key science for monitoring the health status of our world. 6. Mexico, DF, Mexico.
4. Heinz Brendelberger; Peter Martin; Matthias Brunke; Hans Jürgen Hahn. (September 2015). Schweizerbart science publishers. Retrieved from schweizerbart.de
5. Maciej Zalewski, David M. Harper and Richard D. Robarts. (2003). Echohydrology and hydrobiology. Poland: International Center for Echology Polish Academy of Sciences.
6. Manuel Graça, Verónica Ferreira, Cristina Canhoto, Andrea Encalada, Francisco Guerrero-Bolaño, Karl M. Wantzen and Luz Boyero. (2015). A conceptual model of litter breakdown in low order streams. International Review of Hydrobiology, 1-2.
7. Pedro Cervantes-Hernández, Mario Alejandro Gámez-Ponce, Araceli Puentes-Salazar, Uriel Castrejón-Rodríguez and Maria Isabel Gallardo-Berumen. (2016). Spatial variability of the coastal shrimp catch in the Mar Muerto Lagoon System, Oaxaca-Chiapas, Mexico. Hydrobiological, 23-34.
8. Schwoerder, J. (1970). Methods of hydrobiology fresh water biology. Hungary: Pergamon Press.