Human impact on the environment : Practice Questions

The management of natural resources is essential for sustainable development. Which of the following pairs correctly matches a resource with its classification and a significant impact of its overexploitation?

During the secondary treatment process in a sewage treatment plant, air is continuously bubbled through the sewage in an aeration tank. What is the primary biological purpose of this step?

Land reclamation in coastal areas often results in the permanent loss of mangrove habitats. Beyond the direct loss of plant species, which of the following is a long-term ecological consequence of this human activity on the local marine environment?

Acid rain (pH < 5.6) can lead to a decline in forest health by affecting the availability of soil nutrients. Which of the following best explains why acid rain causes a deficiency of magnesium (\(Mg^{2+}\)) and calcium (\(Ca^{2+}\)) ions in the soil?

The use of non-selective fishing methods, such as bottom trawling, often results in a significant amount of bycatch. Explain how this practice specifically hinders the long-term recovery of a depleted fish population.

Persistent organic pollutants, such as polychlorinated biphenyls (PCBs), are non-biodegradable and fat-soluble. Explain the ecological mechanism by which the concentration of these substances becomes highest in apex predators, making them particularly vulnerable to adverse health effects.

Methane and carbon dioxide accumulation contributes to global warming. Explain how an increase in sea surface temperature can lead to a decrease in the primary productivity of open ocean ecosystems by affecting nutrient availability.

Eutrophication is a common problem in many aquatic ecosystems, often exacerbated by human activities.

a) Describe the process of eutrophication in a freshwater body, explaining how excessive nutrient loading from human sources leads to a reduction in water quality and aquatic life. (3 marks)

b) Suggest two distinct measures that can be implemented at an agricultural level to prevent or significantly reduce the occurrence of eutrophication in nearby aquatic environments. (2 marks)

Global warming is a pressing environmental issue with far-reaching effects on ecosystems worldwide.

a) Outline two major human activities that contribute to the enhanced greenhouse effect, leading to global warming. (2 marks)

b) Describe three distinct biological impacts of global warming on ecosystems and biodiversity. Provide specific examples for each impact. (4 marks)

c) Suggest one global-level initiative and one individual-level action that can help mitigate the effects of global warming. (2 marks)