Principles of Soil and Plant Water Relations

M. B. Kirkham is a Professor in the Department of Agronomy at Kansas State University. Her research involves two areas: soil-plant-water relations and uptake of heavy metals by crops grown on polluted soil (called “phytoremediation”). Dr. Kirkham is currently collaborating with colleagues at the Kansas State University Northwest Research-Extension Center in Colby, Kansas to study yield and water relations of sorghum grown under the semi-arid conditions of far western Kansas. Dr. Kirkham serves on several editorial boards: Soil Science; Journal of Crop Improvement; International Agrophysics; Crop Science; Australian Journal of Soil Research; Agriculture, Ecosystems and Environment; Agricultural Water Management; Pakistan Journal of Agricultural Research; Agricultural, Food and Analytical Bacteriology; and Journal of the American Society for Horticultural Science. In addition, Dr. Kirkham has received the CSSA Crop Science Research Award and the 2010-11 Iman Outstanding Faculty Award for Research.

Introduction
Definitions of Physical Units and the International System
Structure and Properties of Water
Soil-Water Terminology and Applications
Tensiometers
Static Water in Soil
Water Movement in Saturated Soil
Time Domain Reflectometry
Dual Thermal Probes
Field Capacity, Wilting Point, Available Water, and the Non-Limiting Water Range
Penetrometers
Oxygen Diffusion Rate
Infiltration
Pore Volume
Root Anatomy and Poiseuille’s Law for Water Flow in Roots
Gardner’s Equation for Water Movement to Plant Roots
Stem Anatomy and Pressure-Volume Curves
Thermocouple Psychrometers
Pressure Chambers
The Ascent of Water in Plants
Sap Flow
Electrical Analogues for Water Movement through the Soil-Plant-Atmosphere Continuum
Leaf Anatomy and Leaf Elasticity
Stomatal Anatomy and Stomatal Resistance
Solar Radiation, Black Bodies, Heat Budget, and Radiation Balance
Infrared Thermometers
Stress-Degree-Day Concept and Crop-Water-Stress Index
Potential Evapotranspiration
Water and Yield
Solar Time and Interception of Direct-Beam Solar Radiation