Question

Which weed is known as the “terror of Bengal”? Why is it very difficult to get rid of them from the water bodies?

Answer 1

Hint: This plant is the most notorious, free-floating, water-borne tropical weed in the world. This grows abundantly in eutrophic bodies of water and contributes to unbalance in the water body's ecosystem dynamics.

Complete answer:
Water hyacinth (Eichhornia crassipes) is widely referred to as “Terror of Bengal” because it is an invasive shrub that competes strongly with the native species and has also replaced many of them. It is an aquatic plant that flourishes in Bengal's hot and humid climate and can live well and kill nearby plankton and water-borne species. Additionally, each plant can produce thousands of seeds annually, and these seeds can remain viable for over 28 years.

Fish in Bengal is the food supplement as well as a symbol of worship too. Fish is a key ingredient in their diet. The water hyacinth is effective in utilizing aquatic nutrients and solar energy for the production of biomass. This leads to a reduction in the number of fish and people are faced with food scarcity. The water hyacinth is also called “Terror of Bengal” due to this shortage of fish in Bengal caused by water hyacinth or Eichhornia crassipes.

Additional information:
Water hyacinth is a perennial aquatic (or hydrophyte) free-floating plant occurring in tropical and subtropical South America or native to the Amazon Basin. Known as one of the fastest-growing plants, water hyacinth reproduces mainly through ‘Offset’ found in plants such as grass/strawberry as a subaerial 'runner' or 'stolon’. Offsets give rise to new plants consequently, water hyacinth shows a rapid growth rate, rapidly invading water surfaces of lakes and ponds. It is an aquatic plant and is also an invasive species that is extremely problematic outside its native range. During British rule, the Europeans introduced it to India for its beautiful look due to its beautiful flowers and leaf design. But this became a serious threat to native aquatic species as an alien species. It was competing with them and they were excluded from their world. It spread across the body of water at an alarming pace. It also reduced the amount of dissolved oxygen in the body of water needed to sustain aquatic life.

Note: Because of its beautiful flowers and shapes of leaves, water hyacinth was introduced in Bengal in India but turned out to be an invasive weed stealing oxygen from the bodies of water and resulted in the death of many fish.