Understanding the 'Terror of Bengal'

The question asks to identify the organism known as the 'Terror of Bengal'. This term is commonly used to describe a particular plant that causes significant ecological and economic problems in aquatic environments, especially in the Bengal region of India and Bangladesh.

Let's examine the provided options to determine which one is referred to as the 'Terror of Bengal'.

Why Eichhornia Crassipes is the 'Terror of Bengal'

The term 'Terror of Bengal' refers to the water hyacinth, scientifically known as Eichhornia crassipes. This plant is native to South America but was introduced to Bengal because of its beautiful flowers. However, it quickly became a highly invasive species due to its extremely rapid growth rate and ability to reproduce vegetatively at an alarming pace.

Here's why Eichhornia crassipes earned this name:

• It forms dense mats on the surface of water bodies, covering large areas.
• These mats block sunlight from reaching the water below, harming submerged plants and algae.
• The rapid decomposition of dead plant material consumes large amounts of dissolved oxygen in the water, leading to oxygen depletion (hypoxia).
• Oxygen depletion can kill fish and other aquatic life, severely impacting biodiversity and local fisheries.
• The dense mats also impede boat navigation, irrigation systems, and hydroelectric power generation.
• It increases water loss through evapotranspiration compared to open water surfaces.

Because of its devastating impact on aquatic ecosystems and human activities, Eichhornia crassipes is widely recognized as the 'Terror of Bengal'.

Analysis of Other Options

Let's briefly look at the other options to understand why they are not referred to as the 'Terror of Bengal'.

• (a) Solanum tuberosum: This is the scientific name for the potato plant. Potato is a terrestrial crop and not an invasive aquatic plant causing 'terror' in water bodies.
• (c) Algal bloom: Algal bloom refers to a rapid increase in the population of algae or cyanobacteria in a water system. While some algal blooms, particularly those caused by cyanobacteria, can be harmful and lead to oxygen depletion and toxin production, 'Terror of Bengal' is a specific name given to the water hyacinth plant, not the general phenomenon of algal blooms.
• (d) Oryza sativa: This is the scientific name for rice, a staple crop cultivated widely, including in Bengal. Rice is a domesticated plant and not an invasive species causing ecological disaster in the sense implied by 'Terror of Bengal'.

Conclusion

Based on the biological and ecological characteristics and the common name associated with significant aquatic invasion in Bengal, the plant known as the 'Terror of Bengal' is Eichhornia crassipes.

Revision Table: Key Terms and Concepts

Additional Information on Aquatic Invasive Species

Invasive aquatic species like Eichhornia crassipes are a major threat to global freshwater ecosystems. Their ability to outcompete native plants, reproduce quickly, and alter the water chemistry can lead to significant loss of biodiversity.

• Impacts: Besides oxygen depletion and blockage of waterways, invasive aquatic plants can also affect water quality by increasing turbidity and altering nutrient cycles.
• Management: Controlling invasive species often involves a combination of methods, including manual removal, biological control (using natural enemies like insects), and chemical control (herbicides), although chemical methods can have their own environmental risks. Prevention of introduction is the most effective strategy.
• Global Issue: While Eichhornia crassipes is the 'Terror of Bengal', many other regions around the world face problems with invasive aquatic plants and animals, highlighting the importance of understanding their ecology and spread.