By Ebele Orakpo
You see it covering large water bodies like a mat, making fishing, boating and other water activities almost impossible as they clog waterways. People hate to love it because despite its luxuriant foliage and very showy lavender flowers, they believe it does more harm than good to man and the environment.
This plant can aptly be described as a sailor’s nightmare. It is water hyacinth, an exotic aquatic plant. It is exotic in the sense that it has a strange allure, beauty and quality.
Although this plant impacts the environment negatively by blocking photosynthesis thereby greatly reducing oxygen levels in the water, which in turn reduces other underwater life such as fish and other plants, research has shown that it has so many beneficial attributes.
In this chat with Vanguard Learning, Miss Ogunlana Ayotide, HND II student of Environmental Biology at the Yaba College of Technology said that despite all the negative attributes, water hyacinth has so many positive attributes. She spoke during the 2012 Yaba College of Technology Conference and Research Fair where she showcased products made from the ‘troublesome’ water hyacinth. Excerpts:
According to Ayotide Ogunlana, her work on water hyacinth was actually her final project in her Higher National Diploma programme. “My main research topic was Turning Waste to Wealth. Water hyacinth has been seen as a pest in the country since 1984 when it entered into the Nigerian waterways.
“It is a plant that takes about two weeks to cover the surface of the water. Under two weeks, you see a large population of the plant on water and when it invades the water body, it is very difficult to eradicate. Unfortunately, many people do not know what to do with it. You can actually make so many things like fertiliser, biogas, paper pulp, soap, basket, slippers, bangles, earrings, wrist watches, fish feeds, cat feeds etc from this pest,” she said.
She said although there have been reports of people using water hyacinth to produce things outside Nigeria, “but here, nobody has actually implemented it so we decided to carry out the research ourselves and see how it really works. It was more like a research, trying to see whether this thing really works and we have tested it and have seen that it works,” she stated.
Getting water hyacinth:
“We go to large bodies of water where it has populated. Example, at the Owode Onirin waterways, you see a large population of the plant there. That was where we collected the samples used in making these products. Other places you can get them are from the Ogun River, Ibadan. In fact, you can get it anywhere that has water,” she said.
Ogunlana noted that the plant is a bio-indicator because “wherever you see water hyacinth, it means that the water is polluted or contaminated. So for you to see water hyacinth in a body of water means that there are pollutants in the water.
“The water hyacinth helps to remove pollutants like heavy metals. It is a mode of phytoremediation (using plants to clean up soils/water); it is a phytoremediation plant. It absorbs these contaminants.”
Source of carotene:
Human beings can use water hyacinth as vegetable as it is a very good source of carotene. She, however, noted that to be on the safe side, it is advisable for one to cultivate it by oneself, within his environment where he is rest assured it will be free from heavy metals.
Handcraft: “If you intend to use it for handcraft like basket, slippers, wristwatch starp, earrings and bangles, all you need is the stem which you sundry. I tried to oven-dry but it did not turn out well. The reason why I will not suggest oven-drying is because when it is oven-dried, it becomes crispy and tends to break and so will not serve the purpose it is meant to serve. But if you sun-dry, you can monitor the texture of the stem while it is drying. If it dries to your satisfaction, you remove and use,” she stated.
Fertiliser: “If you want to use it for fertiliser, all you need is the roots. That is the main ingredient for fertiliser. “
Fish feed:” For fish feed, all you need is just the leaves.”
Biogas: “Water hyacinth, combined with animal waste is an efficient source of biogas.” Sources say it releases about 249.1 m3 of methane per kilogram , enough to produce 9.54 gigajoules (GJ) of energy.
Animal feed: “Water hyacinths are used as low-cost animal feed. In China for instance, sun-dried and chopped water hyacinths have been used to replace alfalfa for breeding rabbits , while cooked hyacinth leaves and stems are an effective supplement in commercial fattening of Yorkshire pigs .
Medicinal use: “The only known medicinal use is that the flower is used as a tonic for medicating the skin of horses. Whenever it is in bloom, you extract the tonic from the purple flower and use it for the horse,” she said.
She appealed to government to help them in their bid to turn this pest to wealth. Reports say that in Florida, USA, millions of dollars are spent yearly on water hyacinth control. So, I believe that if government sees what we have done and decides to help us, we can do more,” Ogunlana said.