The problems and benefits created by the spread of the water hyacinth in Kenya

Water hyacinth (Eichhornia crassipes), an aquatic plant native to South America, was once considered the “world’s worst aquatic weed” when it aggressively invaded Lake Victoria (Kenya), blocking fishing channels and creating breeding grounds for disease-carrying mosquitoes. However, beneath those decaying, waxy green leaves lay a potential “gold mine” of renewable energy. By combining water hyacinth with livestock waste in biogas digesters, local residents have transformed an ecological disaster into a clean fuel source, offering a dual solution to Africa’s firewood crisis and indoor air pollution. The reading passage The problems and benefits created by the spread of the water hyacinth in Kenya (Cambridge IELTS 21 – Test 4, Passage 1) provides a practical perspective, balancing environmental challenges with community livelihoods.

Part of the Ecology, Renewable Energy & Sustainable Development theme, Passage 1, which opens Test 4, features a clear line of reasoning, from the problem and technical mechanisms to social benefits. The test assesses candidates through three familiar question types: True/False/Not Given, Flow Chart Completion, and Note Completion. This