Natural sinkholes generally form when heavy, water-saturated soil causes the roof of an underground limestone cavity to collapse, or when water widens a natural fracture in limestone bedrock.

Soil conductivity represents the conductive capability of soil solution in digital form, reflecting the state of water and salt in the soil.

N in the main form of nitrate through the subsurface runoff was put into the stream, the vegetation-covered riparian had high on the nutrient in the soil water.