Difference Between Eutrophication and Succession

The key difference between eutrophication and succession is that eutrophication occurs in an aquatic body whereas succession occurs in any habitat.

Eutrophication and succession are gradual changes that take place in the environment. They are important processes triggered by both natural and unnatural substances or occurrences that can’t be stopped by men when it has occurred. Eutrophication causes water pollution hence, affects the aquatic flora and fauna. Once the eutrophication occurs, it reduces the light penetration, and also increases the biological oxygen demand and decreases the dissolved oxygen. On the other hand, succession causes to make up a community over time.

CONTENTS

1. Overview and Key Difference
2. What is Eutrophication
3. What is Succession
4. Similarities Between Eutrophication and Succession
5. Side by Side Comparison – Eutrophication vs Succession in Tabular Form
6. Summary

What is Eutrophication?

The term eutrophication originates from the Greek word, eutrophia and the German word Eutrophie, which means adequate nutrition, development, and healthy. Eutrophication occurs due to the accumulation of natural or artificial substances, like phosphates and nitrates, through sewage or fertilizers, in an aquatic system. Thus, this is the condition where there is a great increase or bloom of phytoplankton in the water body. Because of this, the water appears in green colour in a eutrophic water body.

Figure 01: Eutrophication

Here, since the algae grow excessively, it blocks the penetration of sunlight to the bottom of the water bodies. And hence, this leads to the death of different plants including algae due to insufficient sunlight for photosynthesis. Ultimately, microorganisms act on the dead organic matter in the water body and thus, the biological oxygen demand increases. Furthermore, during the microbial decomposition, different toxic material such as gasses release into the environment. Because of this, the eutrophic lakes release bad odours causing environmental pollution. Besides, the other negative effects include the depletion of oxygen present in water and the reduction of animal populations including specific fishes.

What is Succession?

Succession refers to the less or more orderly and predictable changes in the structure or composition configuration of an ecological community. And, this primarily happens by the formation of a new, unoccupied territory (example: severe landslide or lava flow) or from a certain disturbance (logging, wind throw, or fire).

Figure 02: Succession

Besides, succession has two types; they are the primary succession and secondary succession. In primary succession, a habitat colonizes for the first time while in secondary succession, a previously occupied habitat colonizes again after a disturbance or damage. Furthermore, in primary succession, fast-growing and well-dispersed species will dominate while in secondary succession, more competitive species will dominate. In this manner, succession will progress from a community with lower species diversity to a community with higher species diversity.

What are the Similarities Between Eutrophication and Succession?

• Eutrophication and succession are two processes take place in the environment.
• Both can bring good and bad outcomes.

What is the Difference Between Eutrophication and Succession?

Eutrophication is the process of excessive algal growth in a water body due to the accumulation of nutrients such as phosphates and nitrates. On the other hand, succession is a natural process that refers to the gradual change of the species in a community. The key difference between eutrophication and succession is that eutrophication occurs in an aquatic body whereas succession occurs in any habitat.

Moreover, eutrophication can occur due to natural causes such as run-off of nourishment from the soil and weathering of rocks or due to artificial causes or man-made causes such as discharge of detergents that contain phosphates. Whereas, for succession, the causes are mainly natural occurrences like erosion, catastrophic factors, etc. Hence, the cause of occurrence is also a difference between eutrophication and succession.  Furthermore, one other difference between eutrophication and succession is the outcome. That is; eutrophication can cause death and undernourishment in some animals. But, succession creates new territory and also, the changes are very evident. Moreover, when eutrophication worsens, it can dramatically decrease the existence of some species while succession can give another animals shelter of the former territory. Besides, eutrophication happens slowly and sometimes; it is too late for man to do something about it.

Summary – Eutrophication vs Succession

In summarizing the difference between eutrophication and succession; the eutrophication and succession are gradual changes that may happen in an environment. But, eutrophication causes algal blooms due to the enrichment of water bodies by nitrates and phosphates in larger quantities. And, that affects different levels within the water body. It is a type of pollution which causes detrimental effects on the environment. On the other hand, succession refers to more or less an orderly and predictable changes in the structure or composition configuration of an ecological community. It is a natural process and is not a type of pollution. Hence, it does not cause any detrimental effect on the environment.

Reference:

1.“Eutrophication: Causes, Consequences, and Controls in Aquatic Ecosystems.” Nature News, Nature Publishing Group. Available here  
2.“Ecological Succession.” Khan Academy, Khan Academy. Available here 

Image Courtesy:

1.”Potomac green water”By Alexandr Trubetskoy – Own work, (CC BY-SA 3.0) via Commons Wikimedia  
2.”Pond sucession”By Rhaun – Own work, (CC BY-SA 4.0) via Commons Wikimedia