Question

What are the effects of fertilizer input into lakes? select all that apply. select all that apply. fertilizers discolor lake water, preventing algal photosynthesis. fertilizers are toxic to freshwater algae. fertilizers lead to algal blooms that eventually deplete lake oxygen?

Answer 1

The correct answer is: 'fertilizers lead to algal blooms that eventually deplete lake oxygen''. Fertilizers contain nutrients for plant growth, typically nitrogen and phosphorus. Much of the fertilizer applied to farmlands washes off into rivers during rainfall. Water in rivers and lakes can then become rich in nutrients, which is called eutrophication. Algal growth in lakes is typically limited by nutrients, usually phosphorus. This means, any additional input of nutrients into a lake will cause exponential algal growth. An algal bloom will occur with the input of nutrients. This effectively changes the trophic state of the lake. The algal bloom will eventually deplete the nutrients, and the population of algae will experience a mass die-off. Rotting algae will result in anoxic conditions, as decomposition uses up oxygen. This can lead to the death of other aquatic organisms. 

Answer 2

Answer: fertilizers lead to algal blooms that eventually deplete lake oxygen

Explanation:

Fertilizers are the chemical substances which contains inorganic and organic minerals which are required by the plants for their growth. Fertilizers are added to the soil to improve it's quality and fertility. The fertilizers usually contain minerals like phosphorous, and sulfur. These minerals due to surface runoff enter into the neighboring water source such as lakes, ponds and others from the agricultural field. These minerals will be responsible for supporting the extensive growth of aquatic plants and surface water algal bloom. The increase in plant growth will limit the oxygen concentration of the water body which will kill aquatic animals inhabiting the water.