Answer:
The sequence of event is as follows -
1. After heavy rains, nutrient-rich water enters the local aquatic environment, causing a series of events to occur within the ecosystem.
2. An algal bloom occurs.
3. Algae consume the available nutrients and then begin to die oft.
4. Decomposers break down algae and increase in number
5. Decomposers increase oxygen consumption
6. Oxygen depletion, also known as hypoxia, is one result of runoff from over-fertilized lawns or farmland.
Explanation:
Whenever there is a heavy rainfall, runoff is generated from the nearby farmland and cropland. This runoff consists of essential soil nutrients from farmland which ultimately mixes with water bodies such as lake. In a standing water body such as lake, the water become nutrient enriched and the water plants grow uncontrollably thereby causing algal boom.
Algal boom further leads to overproduction and depletion of oxygen from water body. The overly produced algae die and deteriorate the water quality. Also the depleted oxygen create problem for aquatic other plants and animal species.
Hence, the correct order is as follows -
1. After heavy rains, nutrient-rich water enters the local aquatic environment, causing a series of events to occur within the ecosystem.
2. An algal bloom occurs.
3. Algae consume the available nutrients and then begin to die oft.
4. Decomposers break down algae and increase in number
5. Decomposers increase oxygen consumption
6. Oxygen depletion, also known as hypoxia, is one result of runoff from over-fertilized lawns or farmland.