Lake Ecosystem

Nutrients such as nitrogen and phosphorus from agricultural run-off, sewage, and industrial waste can feed algal blooms, leading to their increase. The monsoon brings heavy rains that wash more nutrients from the land into the sea, further contributing to nutrient enrichment of coastal waters and stimulating algal blooms. Upwelling brings nutrient-rich cold water from the deep sea to the surface. These nutrients can fuel the growth of algae, leading to blooms. While upwelling is a natural process, its effects can exacerbate the conditions that lead to harmful algal blooms when combined with excessive nutrient levels from human activities. Therefore, all three factors mentioned in the options can contribute to the increase in harmful algal blooms in the seawaters of India.