Estimating the photosynthetically active radiation under clear skies by means of a new approach
نویسندگان
چکیده
منابع مشابه
Estimation of photosynthetically active radiation under cloudy conditions
Clouds are the largest modulators of the solar radiative flux reaching the Earth’s surface. The amount and type of cloud cover prevailing at a given time and location largely determines the amount and type of solar radiation received at the Earth’s surface. This cloud radiative forcing is different for the different solar spectral bands. In this work, we analysed the influence of cloud radiativ...
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Photosynthetically-active radiation is a necessary input in applications dealing with plant physiology, biomass production and natural illumination in greenhouses. Unfortunately, a worldwide routine network for the measurement of photosynthetically-active radiation is not yet established and it is often calculated as a constant ratio of the broadband solar radiation. This ratio is affected by m...
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Interception of photosynthetically active radiation (PAR) was evaluated relative to greenness and normalized difference [MSS (7 5)/(7 + 5)] for five planting dates of wheat for 1978-79 and 1979-80 at Phoenix, Arizona. Intercepted PAR was calculated from leaf area index and stage of growth. Linear relationships were found with greenness and normalized difference with separate relationships descr...
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Light-emitting diodes (LED), which are designed as quasi-monochromatic light sources, can also function as spectrally selective photodiodes. This provides a new kind of photosynthetically active radiation (PAR) sensor that is inexpensive and has much better stability over time than interference filters used in some PAR sensors. The action spectrum of photosynthesis in green plants has principle...
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Towards closure between measured and modelled UV under clear skies at four diverse sites J. Badosa, R. L. McKenzie, M. Kotkamp, J. Calbó, J. A. González, P. V. Johnston, M. O’Neill, and D. J. Anderson Departament de Fı́sica, Grup de Fisica Ambiental, Universitat de Girona, Girona, Spain National Institute of Water and Atmospheric Research (NIWA), Lauder, New Zealand Cooperative Institute for Res...
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ژورنال
عنوان ژورنال: Advances in Science and Research
سال: 2015
ISSN: 1992-0636
DOI: 10.5194/asr-12-5-2015