Which method is used to reduce nutrient inflows to water sources?

Preventing livestock from entering water sources is an effective method for reducing nutrient inflows. Livestock can significantly contribute to nutrient pollution through waste, which often contains high levels of nitrogen and phosphorus. When livestock have access to water bodies, their waste can directly enter these ecosystems, leading to nutrient enrichment. This process can trigger algal blooms and other ecological imbalances. By preventing livestock from accessing water, the amount of organic waste and associated nutrients that enter the water is minimized, thereby protecting water quality.

The other methods are less effective for this specific purpose. Planting deep-rooted trees can enhance soil stability and reduce erosion but may not directly address nutrient inflows as effectively as restricting livestock access. Using synthetic fertilizers tends to contribute to nutrient loading rather than reduce it, especially when improperly applied. Increasing urban runoff typically results in the transportation of pollutants, including nutrients, into water bodies rather than mitigating their inflow.