Electromagnetic spectrum: Regions relevant to wetlands

Abstract

Given the diversity of wetlands, active and passive remote sensing data acquired in different regions of the electromagnetic spectrum are needed. Optical remote sensing data are particularly useful for retrieving information on the characteristics of the water column (e.g., total suspended matter, chlorophyll-a) but also the subsurface (e.g., substrate) and associated vegetation types. A number of indices and models have been established specifically for retrieval from optical data, with these relating to, for example, water state and vegetation productivity. Thermal infrared data also provide information on the temperature of the land and water surfaces. Data acquired in the microwave regions provide information on the three-dimensional structure of surfaces but also moisture contents and relative roughness. While each region provides useful information on particular aspects of wetlands (e.g., productivity, water pollutants), the integration of data from sensors operating in different modes and regions is advocated.