IELTS Academic
IELTS Academic Reading Practice Test 2
Reading Module • Time allowed: 60 minutes
Total: 40 questions • 3 Passages
Instructions:
Read each passage carefully and answer all questions.
Write your answers in the spaces provided.
For True/False/Not Given questions, write T, F, or NG.
For multiple-choice questions, write the letter of your chosen answer.
For short-answer questions, use NO MORE THAN THREE WORDS.
For exam practice only. Not affiliated with British Council, IDP or Cambridge.
, PASSAGE 1
Coral Reefs Under Threat
Coral reefs are among the most biologically diverse ecosystems on Earth. Covering less than one per
cent of the ocean floor, they support an estimated 25 per cent of all marine species — a
disproportionate richness that has earned them the nickname "the rainforests of the sea." Their value
extends beyond biodiversity: reefs protect coastlines from storm damage, support fisheries on which
hundreds of millions of people depend, and generate billions of dollars annually through tourism. Yet
coral reefs are in grave peril, threatened by a combination of local stressors and the overarching
challenge of climate change.
The primary threat is ocean warming. Corals are highly sensitive to temperature: a sustained increase
of just 1–2°C above their normal range can trigger a process called bleaching, in which corals expel the
symbiotic algae (known as zooxanthellae) that live in their tissues and provide them with up to 90 per
cent of their energy through photosynthesis. Without these algae, corals turn white — bleached — and,
if the temperature stress continues, they will die. Mass bleaching events were virtually unknown before
the 1980s; since then, they have become increasingly frequent and severe, driven by rising sea surface
temperatures linked to global warming.
The Great Barrier Reef, the world's largest coral reef system, has experienced five mass bleaching
events since 1998, with those of 2016 and 2022 being particularly catastrophic. A study published in
Nature found that the proportion of the Great Barrier Reef that escaped bleaching in 2022 was just two
per cent — meaning that 98 per cent of the reef showed some degree of thermal stress. Australian
researchers have documented a 50 per cent decline in coral cover on the Great Barrier Reef over the
past three decades, though the precise figures are contested by some scientists who argue that
recovery in some areas has been underreported.
Ocean acidification presents a related but distinct threat. As oceans absorb carbon dioxide from the
atmosphere, seawater becomes more acidic, reducing the availability of the calcium carbonate that
corals and other shellfish use to build their skeletons and shells. More acidic conditions slow the rate at
which corals can calcify, making their structures weaker and more vulnerable to physical damage from
storms and human activity.
Local stressors compound the damage caused by global climate change. Agricultural runoff delivers
excess nutrients — particularly nitrogen and phosphorus — into coastal waters, stimulating the growth
of algae that compete with corals for space and light. Sedimentation from coastal development
smothers reef surfaces and reduces water clarity. Destructive fishing practices — including the use of
dynamite or cyanide to stun or kill fish — directly destroy reef structures. Untreated sewage and plastic
pollution add further pressure.
Conservation efforts take many forms. Marine protected areas (MPAs) — zones where fishing and other
extractive activities are restricted or prohibited — have been shown to increase reef resilience by
allowing fish populations to recover. Fish play a crucial ecological role on reefs: herbivorous species
graze on algae, preventing the overgrowth that can smother corals after bleaching events. However, the
effectiveness of MPAs depends on enforcement, which remains inadequate in many regions.
More experimental approaches are also being pursued. Coral gardening — the practice of growing coral
fragments in nurseries and replanting them on degraded reefs — has been piloted in the Caribbean,
Florida and Australia. Researchers are also investigating the possibility of breeding heat-tolerant coral
strains that can withstand warmer temperatures. One controversial proposal involves assisted evolution:
deliberately introducing genetic modifications to make corals more resilient to thermal stress. Critics
IELTS Academic Reading Practice Test 2
Reading Module • Time allowed: 60 minutes
Total: 40 questions • 3 Passages
Instructions:
Read each passage carefully and answer all questions.
Write your answers in the spaces provided.
For True/False/Not Given questions, write T, F, or NG.
For multiple-choice questions, write the letter of your chosen answer.
For short-answer questions, use NO MORE THAN THREE WORDS.
For exam practice only. Not affiliated with British Council, IDP or Cambridge.
, PASSAGE 1
Coral Reefs Under Threat
Coral reefs are among the most biologically diverse ecosystems on Earth. Covering less than one per
cent of the ocean floor, they support an estimated 25 per cent of all marine species — a
disproportionate richness that has earned them the nickname "the rainforests of the sea." Their value
extends beyond biodiversity: reefs protect coastlines from storm damage, support fisheries on which
hundreds of millions of people depend, and generate billions of dollars annually through tourism. Yet
coral reefs are in grave peril, threatened by a combination of local stressors and the overarching
challenge of climate change.
The primary threat is ocean warming. Corals are highly sensitive to temperature: a sustained increase
of just 1–2°C above their normal range can trigger a process called bleaching, in which corals expel the
symbiotic algae (known as zooxanthellae) that live in their tissues and provide them with up to 90 per
cent of their energy through photosynthesis. Without these algae, corals turn white — bleached — and,
if the temperature stress continues, they will die. Mass bleaching events were virtually unknown before
the 1980s; since then, they have become increasingly frequent and severe, driven by rising sea surface
temperatures linked to global warming.
The Great Barrier Reef, the world's largest coral reef system, has experienced five mass bleaching
events since 1998, with those of 2016 and 2022 being particularly catastrophic. A study published in
Nature found that the proportion of the Great Barrier Reef that escaped bleaching in 2022 was just two
per cent — meaning that 98 per cent of the reef showed some degree of thermal stress. Australian
researchers have documented a 50 per cent decline in coral cover on the Great Barrier Reef over the
past three decades, though the precise figures are contested by some scientists who argue that
recovery in some areas has been underreported.
Ocean acidification presents a related but distinct threat. As oceans absorb carbon dioxide from the
atmosphere, seawater becomes more acidic, reducing the availability of the calcium carbonate that
corals and other shellfish use to build their skeletons and shells. More acidic conditions slow the rate at
which corals can calcify, making their structures weaker and more vulnerable to physical damage from
storms and human activity.
Local stressors compound the damage caused by global climate change. Agricultural runoff delivers
excess nutrients — particularly nitrogen and phosphorus — into coastal waters, stimulating the growth
of algae that compete with corals for space and light. Sedimentation from coastal development
smothers reef surfaces and reduces water clarity. Destructive fishing practices — including the use of
dynamite or cyanide to stun or kill fish — directly destroy reef structures. Untreated sewage and plastic
pollution add further pressure.
Conservation efforts take many forms. Marine protected areas (MPAs) — zones where fishing and other
extractive activities are restricted or prohibited — have been shown to increase reef resilience by
allowing fish populations to recover. Fish play a crucial ecological role on reefs: herbivorous species
graze on algae, preventing the overgrowth that can smother corals after bleaching events. However, the
effectiveness of MPAs depends on enforcement, which remains inadequate in many regions.
More experimental approaches are also being pursued. Coral gardening — the practice of growing coral
fragments in nurseries and replanting them on degraded reefs — has been piloted in the Caribbean,
Florida and Australia. Researchers are also investigating the possibility of breeding heat-tolerant coral
strains that can withstand warmer temperatures. One controversial proposal involves assisted evolution:
deliberately introducing genetic modifications to make corals more resilient to thermal stress. Critics
