Which is regarded as 'terror of Bengal'

Options

A. Navicula
B. wolfea
C. Noctiluca
D. Water hyacinth

Answer

**Step-by-Step Solution:**

1. **Understanding the Context**: The question asks about a species referred to as the "terror of Bengal." This indicates that the species has a significant negative impact on the ecosystem in Bengal.

2. **Identifying the Region**: Bengal is a water-dependent state, meaning its economy and food sources, particularly fish, rely heavily on water bodies.

3. **Introduction of a Species**: A specific plant species, known as water hyacinth, was introduced into Bengal. Its scientific name is *Eichhornia*.

4. **Purpose of Introduction**: Water hyacinth was initially introduced for its aesthetic value due to its beautiful flowers and attractive leaves.

5. **Reproductive Characteristics**: This plant reproduces asexually at a very rapid rate, which means it can quickly increase its population compared to sexually reproducing plants.

6. **Impact on Aquatic Ecosystem**: As water hyacinth multiplied, it began to cover the surface of water bodies, leading to several ecological problems:
- It consumed aquatic nutrients necessary for other plants and organisms.
- The decomposition of the rapidly dying water hyacinth used up dissolved oxygen in the water.
- It blocked sunlight from reaching aquatic plants below the surface, hindering their growth.

7. **Consequences for Aquatic Life**: The combination of these factors led to the decline of aquatic plants and the death of aquatic organisms, including fish, which are vital for the local food supply.

8. **Conclusion**: Due to its detrimental effects on the aquatic ecosystem and the fish-dependent economy of Bengal, water hyacinth (*Eichhornia*) is referred to as the "Terror of Bengal."

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