Which of the following is a major cause of eutrophication in water bodies?
-
A.
Excessive use of pesticides in agriculture
-
B.
High concentration of phosphates and nitrates
-
C.
Presence of dissolved oxygen in water
-
D.
Dumping of heavy metals into rivers
Correct Answer:
B. High concentration of phosphates and nitrates
Explanation:
Eutrophication is primarily driven by the over-enrichment of water bodies with nutrients, specifically nitrogen and phosphorus. Human activities significantly accelerate this process through the runoff of chemical fertilizers and animal waste from agricultural land, as well as the discharge of untreated sewage and industrial wastewater. These high concentrations of nitrates and phosphates stimulate the rapid growth of algae and aquatic plants. As this excessive organic matter eventually dies and decomposes, bacteria consume the available dissolved oxygen, leading to hypoxic conditions or dead zones that can devastate aquatic ecosystems. While other factors like heavy metals or pesticides impact water quality, they are not the direct drivers of the nutrient-loading cycle that defines eutrophication.
Click below to open Discussion & Feedback
0 Issues
Please
login to comment or Report Issues.