Leukocyte Esterase. Leukocyte esterase is an enzyme present in most white blood cells (WBCs). A few white blood cells are normally present in urine and usually give a negative chemical test result. When the number of WBCs in urine increases significantly, this screening test will become positive.
Land subsidence occurs when large amounts of groundwater have been withdrawn from certain types of rocks, such as fine-grained sediments. The rock compacts because the water is partly responsible for holding the ground up. When the water is withdrawn, the rocks falls in on itself.
Pingo soil formations form when the permafrost layer traps a large amount of water in the soil. When the water freezes, it expands and pushes the saturated earth upward into a large mound or pingo. Solifluction is a soil formation process that occurs when thawed soils slide down a slope over the permafrost layer.ome soils in areas that experience warmer temperatures thaw for a short time during warmer months. The thawing is restricted to the top layer of soil and a permafrost layer remains frozen several inches below the surface.