Soil physics is the study of soil physical properties and processes. Soil physics deals with the dynamics of physical soil components and their phases as solids, liquids, and gases. It draws on the principles of physics, physical chemistry, engineering, and meteorology. Soil physics applies these principles to address practical problems in agriculture, ecology, and engineering. Recent projects include transport and surface exchange of greenhouse gases (nitrous oxide, carbon dioxide, methane), impacts of conventional and organic cropping system on soil properties, and role of unsaturation on shear strength and resilient modulus of pavement materials.