What causes algae blooms?

Question

I realize that excessive fertilizer runoff can cause an algae bloom in bodies of water, but which chemicals are responsible for that? as there are a number of petro chemicals used in agriculture.

Thanks

Answer 1

Nitrates and Phosphates neither of which are petro chemicals, and warm water.

Answer 2

eutrophication (algae blooms) are caused by an enritchment of nutrients in the water, usualy phosphorous is the limiting nutrient although nitrates may have some impact. Petro chemicals may be used in the production of certain pesticides but they are used in such small amounts that they can't be seen as the problem. Likewise natural gas is used to make nitrogen fertalizers but again its not a direct result of using a petro chemical, its the nitrogen that was released from the natural gas. Phosphorus either organic(from manure) or chemical (from fertalizers) is sometimes released if all best management practices are not followed. Best management involves making sure that you apply the recomended amount of fertalizer and apply it away from streams and water sources to help prevent contamination.

Answer 3

an algae bloom is created by favorable conditions for the reporduction of the algae.  Generally a slightly acidic, high phosphorous body of water exposed to adequate sunlight will cause an algae bloom.

It also depends on the type of algae present.

The petrochemicals would normally inhibit algae growth.

Answer 4

earlier phosphates  present in detergents is one of the causes for algae blooms in water bodies.

Answer 5

Nitrates (NO3^-) and Phosphates (PO4^3-)

Answer 6

well, um....

Blooms of Anabaena circinalis (Algae) are caused by high levels of nutrients like phosphorus and nitrogen, washed into the water from fertilisers, urban gardens, roads, and other waste sources. The nutrients from these areas drain into catchment land, which drains into the river system. They feed the algae, which then reproduce very quickly. Excess nutrients have been building up on W.A, riverbeds since European settlement. If the flow was stopped now, we would still have algal blooms for many years.