Model Calculations of Diffuse Attenuation Coefficient Spectra in Lake Waters

Valguse difuusse nõrgenemiskoefitsiendi mudelarvutused järvevete jaoks

Birgot Paavel ； Helgi Arst ； Anu Reinart ； Antti Herlevi

《Proceedings of the Estonian Academy of Sciences. Biology. Ecology》 55卷1期 (2006/03) Pp. 61-81

並列摘要

The reliability of the models elaborated for recreating the spectra of the light attenuation coefficient, K(subscript d, λ), on the basis of its measured values at 1-3 wavelengths was studied. The coefficients of the ”one-point” (490 nm) model, elaborated earlier by A. Reinart and A. Herlevi, were tested and approved using 43 new spectra of underwater irradiance measured in 1999-2000. A new version (named C-model) allowing recreation of the spectrum of K(subscript d, λ) on the basis on its measured values at three wavelengths was elaborated and tested by statistical analysis. The C-model was found to enable to reconstruct the spectra of K(subscript d, λ) with high reliability. Both models gave truthful values of K(subscript d, PAR) (mean value of K(subscript d, λ) in the region 400-700 nm). For the estimation of the reliability of the experimental initial data, the values of K(subscript d, λ) derived from in situ measurements by an underwater spectrometer LI-1800 UW and an instrument ac-9 were compared. The results showed that K(subscript d, λ) (ac-9) is mostly lower than K(subscript d, λ) (LI-1800 UW), the differences increasing with wavelength.

並列關鍵字

marine optics ； limnology ； underwater light field ； light attenuation coefficient