AGR 2320 Lecture Notes - Lecture 15: Water Potential, Loam, Surface Tension
14 Oct 2016
School
Department
Course
Professor
Document Summary
Agr 2320 lecture 15 rainfall"s effects on soil, and introduction to water. Rainfall increases chances for erosion b/c water drops break apart soil particles into smaller parts. If little drainage, this increases chances for erosion b/c water is just lying on top. Impact of management is primarily on soil structure: minimal direct effects on texture. Practices that reduce incidents of serious compaction: esp. med. and fine textured soils reduce axle load reduced tire pressure radial tires vs bias ply. Water reserves total water = 1. 4x109 km3: oceans: 97% fresh water: 0. 05% lakes 60% 284 mm through gravity and percolation into groundwater. How good is the soil infiltration rate. In terrestrial ecosystems water is almost always at interfaces: water/air, water/solid. At interfaces there are different forces: cohesion (between water molecules, adhesion (between water molecules and surfaces, gravity. Balance of forces at interfaces (in a capillary)
