Thermal and Other Remote Sensing of Plant Stress

In this paper we outline the ways in which thermal and spectral remote sensing can be used to diagnose and monitor effects of environmental stresses on plants. Following an introduction to the theory and practice of using thermal sensing to study plant water relations and stresses involving stomatal closure, the discussion is widened to cover a range of imaging technologies. Particular emphasis is placed on the relationship between various stresses and responses detectable using imaging technologies. Various approaches for the combination of thermal remote sensing with spectral remote sensing, especially to distinguish plant from background, and otherwise to enhance the diagnostic powers of the technology, are outlined. The advantage of using a multi-sensor approach for stress diagnosis is highlighted and some possible applications summarized.