Which factor can negatively affect the absorption capacity of effluent in soil?

High clay content in soil can indeed negatively affect the absorption capacity of effluent. Clay particles are very fine and compact tightly together, which creates a dense matrix with very little pore space for water or effluent to move through. This leads to reduced permeability and can create conditions where the soil becomes saturated quickly, preventing further absorption. Consequently, when effluent is discharged into soil with a high clay content, it can result in surface runoff or pooling rather than being effectively absorbed and filtered by the soil.

The other factors can influence soil absorption differently: low moisture content may actually improve effluent absorption as drier soils can take in more liquid until they become saturated; high temperatures can increase evaporation rates and may not directly affect soil absorption capacity; and vegetation diversity can enhance nutrient uptake and create a healthier soil ecosystem, helping improve overall soil function, including absorption.