IELTS - Listening - Real test - 01 - Water Hyacinth 🌸

John, how is it going with your research on water hyacinth?Well, I went on a field trip on my own and collected the (1)      data.

After I came back, I also referred to the (2)      data.

So, what do you know about this plant?The water hyacinth grows in (3)      countries. It has beautiful purple blue flowers, but everybody hates it.

Why is that?The water hyacinth, as the world’s worst (4)      aquatic plant, has attracted significant attention.

Millions of these plants grow in rivers and lakes and are brought huge environmental and (5)      problems to the local people.

Farmers cannot travel in boats on the water and thus cannot (6)      in it.

In addition, heavy free-floating mats of water hyacinth are clogging the (7)      at the power station in West Africa. Turbines of the power station are often shut down because of the intertwined leaves.

Dams often cease to function as a result, severely restricting the (8)      generation.

Dense mats of water hyacinth also shade the surface and prevent algae growth, thus limiting the production of (9)      and threatening the survival of fish.

So, where did water hyacinth originate from?The water hyacinth is native to the (10)      basin in Latin America.

It has spread mainly to the tropics and subtropics in much of the world since the (11)   .

Later, it was introduced into Europe and Africa as an (12)      garden pond plant due to its beauty.

Flowers of this plant were being sold in local markets in African countries as a source of (13)      for women.

Since the 1900s, this weed has infested lakes, rivers and creeks of the delta areas in West (14)   .

I guess whoever introduced this plant had never expected the disastrous impact it would have on the local (15)      environment.

What kind of habitat does water hyacinth thrive most in?   

It’s been discovered that the (16)   -rich environment contributes significantly to the rapid proliferation of this weed,

which obtains its nutrients directly from the (17)   .

Why is that?The main reason for soil nutrient loss is that local residents cut down (18)   . Excessive deforestation accelerates soil (19)

Without enough trees to retain nutrients in the soil, frequent rain might partly aggravate this by carrying some of the nutrients into the (20)   .

Are there any effective measures to control or even eradicate this weed?Yes. A number of approaches have been widely applied throughout the world. Among them, (21)      control is the most widely favored long-term control method

by introducing a type of insects that (22)      on the water hyacinth.

So far, (23)      has used this method for six months.

However, water hyacinth won’t be removed immediately and the side effects of this method on local ecology will remain (24)      for years.

Then what about other approaches?Well, the (25)      removal of water hyacinth is seen as the best short-term solution.

This method can immediately open physical space for fish and (26)      traffic. It is,

however, inefficient for workers to process extensive areas and costly to use large cutting and (27)      equipment.

Ironically, it costs even more to (28)      this plant than to remove it.

Can we make use of this weed and turn it into something good?Now scientists think that water hyacinth can be useful. The plant itself, although more than 95% (29)   ,

has a fibrous tissue and a high energy and (30)      content.

So, what do people do with water hyacinth that is initially removed?First, the cut-down water hyacinth is left to dry under the sun for a few days before being mixed with ash and animal (31)   .

The mixture can be used as alternative (32)      rather than fertilizer.

Mushroom farmers can benefit from water hyacinth as well. Mushrooms generally grow much faster so that farmers can harvest mushrooms sooner, which enables them to make money more (33)   .

It can be used to grow oyster and (34)      mushrooms.

In (35)   , attempts have been made to grow edible mushrooms organically utilizing water hyacinth.

In South East Asia, people feed cows using chopped water hyacinth mixed with other vegetables. Then the waste from the cows is treated to produce (36)      gas,

which can be used as fuel for cooking, lighting or powering an (37)   .

With global warming getting worse, developing alternative sources of energy will be more urgent than ever. Maybe in the future people will (38)      water hyacinth instead of hating it.