If excess fertilizer is mixed with the water,it causes algal bloom as the number of phytoplankton increases at the initial stage due to intake of large amount of nutrients that are obtained from the fertilizers.
Explanation:
The nutrients that are mainly found in fertilizer are nitrogen and phosphorus that mainly helps for growth and development of plants.Fertilizers that are applied in the agricultural field are rich in nutrients and minerals that enters into the water stream through runoff and disturbs aquatic environment by reducing the oxygen content in the water due to algal bloom,emits odour and gas in the air,release toxic substance that kills many aquatic organisms,decrease water quality,increase level of pathogen that creates life threatening diseases etc.
The concept of reproductive isolation relates more toward genetic similarities to distinguish between species. The barriers prevent closely related species living in the same geographical area from interbreeding. They help to keep each species distinct from the others.
