What are Water Quality Indicators (WQIs)?

Water Quality Indicators (WQIs) are measurements used to assess the quality of water. They provide critical data regarding various physical, chemical, and biological factors that determine whether water is safe for human consumption, aquatic life, and recreational activities. Common examples of WQIs include parameters such as pH level, turbidity, dissolved oxygen, and concentrations of pollutants like nitrates and phosphates. By analyzing these indicators, water quality can be effectively monitored and managed to ensure environmental health and safety.

The other options do not pertain to the definition of WQIs. Weather indicators focus on atmospheric conditions, tools for measuring temperature relate to a specific physical aspect of water but do not encompass overall quality, and markers indicating water flow direction deal with hydrodynamics rather than water quality assessment.