Water hyacinth, also known as water hyacinth, is a perennial aquatic plant. It likes to float freely on the water. Its lavender flowers are very beautiful. In the early 20th century, it was introduced into China as an ornamental species, and then promoted and planted as pig feed and water purification plants. Now it is widely distributed in most parts of China. Its asexual reproduction speed is very fast. Under suitable conditions, it can reproduce a new plant every five days. Not only that, it can bloom and bear fruit for sexual reproduction at the same time, and a flower can bear about 300 seeds.
Because water hyacinth has such amazing reproductive ability, it has formed a single dominant community in many rivers, lakes and ponds. According to rough statistics, there are about 130000 water hyacinths on one mu of water surface, and the total weight of all is about 20 tons! After a large number of growth and reproduction, water hyacinth forms a single dominant species, resulting in the reduction or even disappearance of other aquatic plants. It can not only reduce the penetration of light into the water body and affect the growth of underwater organisms, but also reduce the concentration of dissolved oxygen in the water, increase the concentration of carbon dioxide in the water and reduce the output of aquatic products, which is extremely unfavorable to aquatic animals and plants and water purification.
Due to the excessive reproduction of water hyacinth, it has spread into a disaster and become a headache malignant weed. After the Yangtze River and Han River were invaded by this green devil, some waters even appeared the phenomenon of water and grass locking the river, which had a great impact on shipping, fisheries and other related water activities. In fact, water hyacinth has brought endless disasters not only to China, but also to all parts of the world. As early as the early 20th century, the inland waterways in the Gulf of Mexico were completely blocked by water hyacinths, making passing ships impassable. To make matters worse, fish and other organisms in the water die in large numbers due to lack of oxygen. Later, the US Congress ordered the army to dredge the river and use explosives and flame throwers to deal with the water hyacinth. Unexpectedly, the charred water hyacinth germinated earlier and grew more vigorously the next year. It was not until 1951 that the engineering troops used a new type of water lawn mower, and finally opened up a waterway more than 10 meters wide on the blocked river, and combined with the use of herbicides, that they managed to control the further flooding of water hyacinth. Now, water hyacinth has become one of the most troublesome invasive plants in the world.
What is an invasive plant? Scientists define it as a plant that evolves in a non original ecosystem, migrates to a new ecological environment through unnatural ways, and then settles, builds groups and diffuses to gradually occupy the habitat, and poses a certain threat to the ecological environment or indigenous species and biodiversity. For example, water hyacinth, whose ancestral home is in South America, is a typical representative of invasive plants. Because they have extensive adaptability and strong reproductive ability, they can pose a serious threat to the biodiversity of "invasive territory".
In particular, it is worth mentioning that once the invasion of alien species is successful, it is very difficult and expensive to eradicate them completely. The above examples of biological invasion tell us that human beings must not blindly destroy the ecological balance formed after long-term natural selection and interaction, because whether a species is extinct or over breeding, it will endanger the survival of dozens of species related to it, lead to the imbalance of ecological balance and cause serious social and economic losses.