Plants have the real ability to purify sewage. Water hyacinth is one of them.
The appearance of water hyacinth is full of vitality. The bright turquoise leaves were packed with water. Lavender flowers are very beautiful. The middle and lower part of the petiole suddenly swelled, just like a gourd in water. In fact, it is a spongy tissue, which contains a lot of air, making the whole plant float lightly on the water like a boat. Its roots are very long, just like a beard. Its hometown is Venezuela in Latin America, but now the water hyacinth has traveled to more than 50 countries.
Water hyacinth likes to grow quietly in places with slow water flow. It has a strong vitality, and surprisingly, there are no diseases, insects and natural enemies that can harm water hyacinth in the natural environment. As long as the environment is suitable, only ten water hyacinths can breed to 600 thousand in eight months! The yield per mu is more than 200,000 Jin. The fertilizer efficiency is equivalent to 2000 ~ 4000 Jin of chemical fertilizer. It is thirty or forty times that of green manure such as Chinese milk vetch and alfalfa. What a considerable number!
The removal rate of harmful substances such as phenol, chromium and cadmium in water by water hyacinth is 65438 06%, which is higher than that of ordinary aquatic plants by 25% and 8% respectively. In addition, the magic of water hyacinth is that it can decompose phenol and cyanide and reduce their toxic effects.
In the place where water hyacinth grows, the number of algae, diatoms and trematodes that can pollute the water body is greatly reduced, while the number of fish food-plankton is significantly increased. Therefore, fish grow fast and the yield is obviously improved. Frogs and turtles like to live here, and even birds fly back.
In addition, water hyacinth can absorb metal substances in water. One acre of water hyacinth absorbs 75 grams of silver in mining wastewater every four days, and the absorption effect of gold, mercury, lead, nickel and other metals is similar. It is economical and effective to remove toxic substances from rivers and industrial wastewater.
Water hyacinth can also effectively absorb nitrogen and phosphorus contained in water. In the dense area of water hyacinth, water hyacinth on the water surface can absorb 2.4 grams of nitrogen per square meter per day, 2.45 kilograms per ton of leaves and 3.28 kilograms per ton of roots.
Water hyacinth also has a certain ability to absorb and accumulate arsenic. Another experiment showed that each kilogram of water hyacinth could remove 258 mg of organic sludge in seven days.
Many countries are breeding water hyacinth in large quantities, because it is the most economical "treasure gourd" for naturally purifying sewage.