Measurement of grassland evaporation using a surface-layer scintillometer
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چکیده
منابع مشابه
Measurement of grassland evaporation using a surface-layer scintillometer
A dual-beam surface-layer scintillometer (SLS) was used to estimate sensible heat flux (H) every 2 min for a path length of either 50 or 101 m, for more than 30 months in a mesic grassland in eastern South Africa. The SLS method relies on Monin-Obukhov similarity theory, the correlation between the laser beam signal amplitude variances and the covariance of the logarithm of the beam signal ampl...
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Accurate estimates of actual crop evapotranspiration (ET) are important for optimal irrigation water management, especially in arid and semi-arid regions. Common ET sensing methods include Bowen Ratio, Eddy Covariance (EC), and scintillometers. Large weighing lysimeters are considered the ultimate standard for measurement of ET, however, they are expensive to install and maintain. Although EC a...
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Introduction: With increasing focus on the detection, study and treatment of early stage osteoarthritis (OA), there is increasing interest in novel imaging modalities capable of detecting changes in various joint tissues during early stages of the disease. The surface of the meniscus consists of a relatively thin layer of randomly orientated collagen fibers that overlays the circumferential col...
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The structure constant of the atmospheric refractive index is used for characterizing the turbulence strength and for predicting the scintillation of electromagnetic waves in atmosphere. It is measured continuously in Prague using an optical scintillometer. First monthly and seasonal statistics obtained from the data gathered in the summer 2011 are provided. Lognormal distribution parameters ar...
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Measurements of evaporation were made from July to November 1999 using the eddy correlation method on two wetland types – wet grassland and reedbeds – in south west England. The evaporative water use of a reed bed exceeded that of the grassland wetland by 15% (or 50mm over the 5 months). The evaporation rates at both sites exceed of the Penman Potential Evaporation estimates calculated for this...
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ژورنال
عنوان ژورنال: Water SA
سال: 2010
ISSN: 0378-4738
DOI: 10.4314/wsa.v36i1.50901