What a Long-Running Environmental Trial Established
About this practice test
A detailed account of a long-term floodplain restoration trial comparing planting, engineering and natural recovery, and examining resilience, soil carbon, species richness and the limits of applying its findings elsewhere.
What you’ll practice
Finding detail
Locate specific information and evidence.
Interpreting ideas
Connect main points and inferences.
Evaluating arguments
Assess claims, evidence, and limitations.
What to expect:
12 questions with explanations to review after submission.
Study the questions and tasks
Work through the material below, or start the interactive practice above to complete an attempt. Try the exercises before opening any answer or transcript sections, then use them to review your work.
- Practice level
- C2. Try this level if you can follow the instructions and understand most of the language; choose an earlier level if you need more support.
- Question formats
- True / False / Not Given
How to approach this practice
Read the passage for its main idea, then return to the relevant sentence or paragraph for each question. Base answers on the passage.
What a Long-Running Environmental Trial Established
The trial began in 1991 on a tired stretch of floodplain behind a defunct brickworks, where salt had crept into the soil and the ground had been scraped bare by machinery. Its founders were not trying to produce a comforting conservation story. They wanted a long answer to a simple but awkward question: when a damaged landscape is given time, which matters more, deliberate intervention or room to recover on its own? The site was divided into matched plots and assigned different treatments that reflected the arguments of the day. Some plots were seeded with one fast-growing species. Others received a mixture of native grasses, rushes, and low shrubs. A third set was lightly engineered with compost ridges and channels to slow water. One strip was left to recover with no planting at all. At the time, the choice seemed quarrelsome. The council wanted visible improvement within a budget cycle; the university team insisted that speed and success were not the same thing. They agreed only on a few practical rules. Each plot had to begin with the same shallow soil, the same exposure to tidal spray, and the same ban on fertiliser after establishment. The researchers installed sensors for moisture and salinity, marked every stem, and returned several times a year to record vegetation, invertebrates, and sediment movement. Because the site was vulnerable to geese, temporary fencing remained in place during the first seasons, but otherwise the plots were left as similar as possible. The earliest results were easy to misread. The monoculture plots looked neat from a distance and were the quickest to make the ground appear green. Yet the mixed plots were already producing a different kind of order. Their canopies were uneven, but that irregularity shaded the soil, slowed evaporation, and encouraged more insects. In one low corner, a stand of rushes captured silt after heavy rain so effectively that the surface rose by several centimetres in a single autumn. The recovery strip was harder to praise at first. It remained patchy and raw, and for a few years it seemed to confirm the anxious view that a damaged site left alone simply drifts. Then came the storm in the ninth year. A surge from the estuary overtopped the outer bank, flattened several seedlings, and left a layer of brackish water over the plots for nearly two days. Afterwards, the differences sharpened. The single-species plots survived, but they lost more topsoil and took longer to regain cover. The mixed plots suffered visible damage, yet their root systems held the soil more firmly and their recovery was faster. Even so, the researchers resisted the temptation to call the result a universal victory for diversity. One heavily mulched plot in the engineered set retained moisture so well that it outperformed the others for biomass in a dry summer, though only temporarily. By the fifteenth year, the team was able to say something more exacting than simply that mixed is better. Soil carbon had increased across most of the site, but not where the leaf cover was thickest. In several plots, root depth and the age of buried organic matter mattered more than the quantity of green growth above ground. The control strip, once expected to remain a cautionary blank, had also changed. Wind-borne seeds from neighbouring marshes settled there, and native plants began to establish without deliberate help. That did not make it a perfect replica of the planted plots; it made it a reminder that abandoned land is still active land. The researchers changed their own behaviour. After the third summer, they stopped watering the plots except in the rarest emergency. This decision did not reflect indifference. It was taken because the team wanted to learn whether the systems could become self-supporting, rather than dependent on regular rescue. A separate group in the department argued that continued irrigation would have made the early data easier to interpret, but the original investigators considered that convenience a poor substitute for realism. From then on, their interest shifted from establishment to endurance. That shift exposed another complication. Species richness by itself was not enough. A plot could hold many species and still be fragile if one of them dominated the root zone or if the soil chemistry favoured only a narrow set of competitors. Conversely, a simpler plot could become unexpectedly stable if its plants occupied different layers of the ground. The most resilient areas were not the prettiest, and the prettiest were not always the most productive. In internal notes, one ecologist joked that the site had become a lesson in manners: systems that behave nicely under calm conditions are not necessarily the ones that cope under pressure. The trial therefore altered the way local planners talked about restoration. They stopped asking which treatment would win and began asking which failures could be tolerated. That was a subtler question, and a more practical one. A landscape meant to absorb stormwater, store carbon, and provide habitat will never be judged on a single axis. It must survive drought, salt pulses, neglect, and the occasional well-intentioned mistake. The old assumption that a restored site should quickly resemble an idealised reference area gave way to a less tidy but more durable ambition: to build landscapes that can change without collapsing. Yet the trial was not an oracle, and the authors were careful to say so. The plots lay on a particular soil, under a particular climate, and beside a particular estuary. Another region with deeper loam, fewer tides, or different herbivores might reward a different design. The team never claimed to have proved that engineered ridges are useless, or that low intervention is always cheaper once all costs are counted. They also did not monitor every possible outcome. Some things, such as bird nesting in the rougher plots, were noted only informally and never made part of the formal protocol, which is why the published record stays silent on them. What the trial established, after more than two decades of patient comparison, was not a slogan but a boundary. Diversity, structure, and time each mattered, but none of them worked alone. Intervention could help a damaged site begin, yet a site that depended entirely on management remained vulnerable to the next interruption. The strongest plots were those that combined a degree of design with the capacity to reconfigure under stress. That conclusion was less dramatic than a simple winner, but it was also more useful. It suggested that restoration should be judged not only by how it looks when things are calm, but by what it can absorb before it fails.
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Question 1 · True / False / Not Given
Decide whether the statement agrees with the information. Choose Not Given when the text or recording does not provide the information.
The trial was designed to answer a difficult ecological question rather than to present a reassuring success story.
Return to the passage, recording or visual- True
- False
- Not Given
Check answers and explanations
- Answer
- True
True is correct because the passage says the founders were not trying to produce a comforting conservation story and instead wanted a long answer to an awkward question. False reverses that priority. Not Given is wrong because the motive is stated directly.
Its founders were not trying to produce a comforting conservation story. They wanted a long answer to a simple but awkward question
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Question 2 · True / False / Not Given
Decide whether the statement agrees with the information. Choose Not Given when the text or recording does not provide the information.
In the early years, the mixed plots looked tidier than the monoculture plots.
Return to the passage, recording or visual- True
- False
- Not Given
Check answers and explanations
- Answer
- False
False is correct because the passage says the monoculture plots looked neat from a distance, while the mixed plots were uneven. True reverses that comparison. Not Given is wrong because the contrast is explicit.
The monoculture plots looked neat from a distance and were the quickest to make the ground appear green. Yet the mixed plots were already producing a different kind of order
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Question 3 · True / False / Not Given
Decide whether the statement agrees with the information. Choose Not Given when the text or recording does not provide the information.
The site was later opened as a public park.
Return to the passage, recording or visual- True
- False
- Not Given
Check answers and explanations
- Answer
- Not Given
Not Given is correct because the passage mentions restoration, planning and formal monitoring, but never says the site became a public park. True is unsupported, and False is not justified because the opposite is never stated either.
The council wanted visible improvement within a budget cycle; the university team insisted that speed and success were not the same thing
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Question 4 · True / False / Not Given
Decide whether the statement agrees with the information. Choose Not Given when the text or recording does not provide the information.
Soil carbon rose most in the plots with the thickest leaf cover.
Return to the passage, recording or visual- True
- False
- Not Given
Check answers and explanations
- Answer
- False
False is correct because the passage says soil carbon increased across most of the site, but not where the leaf cover was thickest. True directly contradicts that qualification. Not Given is wrong because the claim is addressed explicitly.
Soil carbon had increased across most of the site, but not where the leaf cover was thickest
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Question 5 · True / False / Not Given
Decide whether the statement agrees with the information. Choose Not Given when the text or recording does not provide the information.
The trial showed that a high number of species on its own is enough to make a plot resilient.
Return to the passage, recording or visual- True
- False
- Not Given
Check answers and explanations
- Answer
- False
False is correct because the passage states that species richness by itself was not enough and explains that dominance in the root zone or soil chemistry could still make a plot fragile. True reverses the argument. Not Given is wrong because the passage directly addresses the claim.
Species richness by itself was not enough
A plot could hold many species and still be fragile if one of them dominated the root zone
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Question 6 · True / False / Not Given
Decide whether the statement agrees with the information. Choose Not Given when the text or recording does not provide the information.
The researchers compared the floodplain with a second trial in another country before drawing conclusions.
Return to the passage, recording or visual- True
- False
- Not Given
Check answers and explanations
- Answer
- Not Given
Not Given is correct because the passage limits the work to one floodplain beside one estuary and never mentions another country or another trial. True is unsupported, and False is not the best label because the text does not directly deny it; it simply leaves it unmentioned.
The plots lay on a particular soil, under a particular climate, and beside a particular estuary
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Question 7 · True / False / Not Given
Decide whether the statement agrees with the information. Choose Not Given when the text or recording does not provide the information.
Researchers continued watering the plots for the whole duration of the project.
Return to the passage, recording or visual- True
- False
- Not Given
Check answers and explanations
- Answer
- False
False is correct because the text says watering stopped after the third summer except in rare emergencies. True contradicts that. Not Given is wrong because the timing is explicit.
After the third summer, they stopped watering the plots except in the rarest emergency
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Question 8 · True / False / Not Given
Decide whether the statement agrees with the information. Choose Not Given when the text or recording does not provide the information.
The team stopped watering because they wanted to see whether the plots could become self-supporting.
Return to the passage, recording or visual- True
- False
- Not Given
Check answers and explanations
- Answer
- True
True is correct because the passage explicitly says the decision was taken so the team could learn whether the systems could become self-supporting rather than dependent on rescue. False contradicts that motive. Not Given is wrong because the reason is stated directly.
This decision did not reflect indifference. It was taken because the team wanted to learn whether the systems could become self-supporting
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Question 9 · True / False / Not Given
Decide whether the statement agrees with the information. Choose Not Given when the text or recording does not provide the information.
The published record gave the exact annual maintenance cost of each plot.
Return to the passage, recording or visual- True
- False
- Not Given
Check answers and explanations
- Answer
- Not Given
Not Given is correct because the passage discusses what was and was not formally monitored, but it never gives annual maintenance costs for the plots. True is unsupported, and False is too strong because the text does not explicitly mention maintenance costs at all.
They also did not monitor every possible outcome
Some things, such as bird nesting in the rougher plots, were noted only informally and never made part of the formal protocol
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Question 10 · True / False / Not Given
Decide whether the statement agrees with the information. Choose Not Given when the text or recording does not provide the information.
The different treatments were assigned so that competing restoration ideas could be compared under the same starting conditions.
Return to the passage, recording or visual- True
- False
- Not Given
Check answers and explanations
- Answer
- True
True is correct because the site was divided into matched plots and the treatments reflected the arguments of the day, while the later paragraph says each plot had the same shallow soil and exposure. False ignores that shared baseline. Not Given is wrong because both assignment and comparison are stated.
The site was divided into matched plots and assigned different treatments that reflected the arguments of the day
Each plot had to begin with the same shallow soil, the same exposure to tidal spray
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Question 11 · True / False / Not Given
Decide whether the statement agrees with the information. Choose Not Given when the text or recording does not provide the information.
The researchers used satellite images to track changes in vegetation throughout the trial.
Return to the passage, recording or visual- True
- False
- Not Given
Check answers and explanations
- Answer
- Not Given
Not Given is correct because the passage describes sensors, marked stems and repeated visits, but never mentions satellite images. True is unsupported, and False is not justified because the text does not explicitly say that satellite images were not used.
The researchers installed sensors for moisture and salinity, marked every stem, and returned several times a year to record vegetation, invertebrates, and sediment movement
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Question 12 · True / False / Not Given
Decide whether the statement agrees with the information. Choose Not Given when the text or recording does not provide the information.
The storm in the ninth year showed that looking healthy early on did not guarantee the best recovery after stress.
Return to the passage, recording or visual- True
- False
- Not Given
Check answers and explanations
- Answer
- True
True is correct because the storm damaged all the plots, and the single-species plots that had looked quick to green recover more slowly than the mixed plots. False misses the contrast between appearance and resilience. Not Given is wrong because the effect is described in detail.
Then came the storm in the ninth year
The single-species plots survived, but they lost more topsoil and took longer to regain cover. The mixed plots suffered visible damage, yet their root systems held the soil more firmly and their recovery was faster
What to review next
Find the words that support each answer. For a mistake, compare the question with the evidence and identify the detail or inference you missed.
A focused practice result shows how you did on these tasks. Use several activities across skills to decide what to study next; one practice score does not certify an overall CEFR level.
Before you practise: a worked example
Look for evidence in the text. Separate what the writer says from what you already know about the topic.
The library normally closes at six, but on Fridays it stays open until eight. When does it close on Friday?
The answer is eight. But introduces an exception to the normal closing time, so the first time mentioned is not the answer.
This teaching example is separate from the scored questions. After your test, compare any mistakes with the explanation and revisit the topic before trying again.