What are the possible effects of over fertilisation on aquatic wildlife

Over fertilisation is heavily linked to leeching and eutrophication. By adding more fertilisers and minerals to the soil, the soil is more likely to become saturated. Therefore, when it rains, the soluble fertilisers will be carried away by the rain. Concentrations of minerals such as nitrates and phosphates will increase in water as a result. Eutrophication will encourage the growth of algae. Green algal blooms will form over the water surface, preventing sunlight reaching aquatic plants. The aquatic plants therefore die as they can no longer photosynthesis. Consequently, bacteria decompose the dead plants and in doing so, they respire, using up the oxygen in the water. The water will become anoxic, making it difficult for aquatic insects and fish to live and the lake may become anoxic, making it difficult for aquatic insects and fish to live and the lake will become lifeless. Hypoxia and anoxia are known to kill fish, resulting in a decrease in the biodiversity of aquatic organisms.