Techniques for solar dosimetry in different ecosystems

Abstract

Over exposure to UV radiation can cause serious damage to the human body resulting in skin cancer and sun-related eye disorders. Furthermore, agricultural production can be influenced by higher levels of solar UV and visible radiation due to atmospheric change, for example cloud cover resulting from climate change. Research into the effects of solar radiation on different ecosystems is of particular significance in order to determine any associated consequences that changes in solar radiation levels may cause. In order to optimise the solar radiation exposure of different ecosystems such as, agricultural crops and fisheries, a complete understanding of the solar radiation environment is necessary. This paper describes the development of dosimetric techniques for the measurement of solar UV exposures and photosynthetically active radiation in different environments in order to provide an improved characterisation of the solar radiation environment for different ecosystems. The UVB (280-320 nm) exposures to plants during various times of year have been measured with polysulphone dosimeters. These dosimeters have been miniaturized in order to increase the number of environments in which they can be used for measurement of UV exposures. At the same time as the measurement of the UVB exposures to plant leaves, the photosynthetically active radiation has been measured with a dosimeter sensitive to the visible waveband. The dynamic range of polysulphone at a sub-tropical site is approximately one day in summer. For periods of exposure longer than this, the polysulphone dosimeters have been replaced on a daily basis or alternatively a dosimeter based on polyphenylene oxide with a dynamic range that is approximately four times longer than that of polysulphone has been employed.