SCIENCE
ECOLOGY
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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nitrogen compounds are recycled
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the concentration of oxygen drops below the necessary level
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an algal bloom occurs
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algae begin to die and decomposers take over
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Detailed explanation-1: -An overabundance of nutrients-primarily nitrogen and phosphorus-in water starts a process called eutrophication. Algae feed on the nutrients, growing, spreading, and turning the water green. Algae blooms can smell bad, block sunlight, and even release toxins in some cases.
Detailed explanation-2: -The overgrowth of algae consumes oxygen and blocks sunlight from underwater plants. When the algae eventually dies, the oxygen in the water is consumed. The lack of oxygen makes it impossible for aquatic life to survive.
Detailed explanation-3: -Harmful algal blooms contain cyanobacteria that can cause skin irritation, gastrointestinal illnesses, and in some cases, produce toxins that cause serious health impacts to people, livestock, and pets. You can be exposed to the harmful effects of cyanobacteria by: Getting them on your skin while swimming or wading.
Detailed explanation-4: -Excessive nutrients lead to algal blooms and low-oxygen (hypoxic) waters that can kill fish and seagrass and reduce essential fish habitats.
Detailed explanation-5: -Algae blooms can occur when a combination of suitable environmental conditions exist for abundant algal growth (e.g., increased nutrients, warmer temperature, abundant light, and stable wind conditions).