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PubMed · 16114677

Light attenuation parameters for waste stabilisation ponds.

S Heaven·C J Banks·E A Zotova
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Abstract

Effective modelling of shallow water ecosystems, including waste stabilisation ponds, is strongly dependent on the availability of good estimates of the light attenuation coefficient k (m(-1)). Experimental data is presented on its determination using purpose-built laboratory apparatus with a near-parallel halogen light source and an array of photodiodes allowing measurements of irradiance at different depths. The equipment was used to compare k values from 4 different pure cultures, and mixed cultures of algae taken from a pilot-scale WSP. Laboratory values were compared with in situ measurements in the pond. At concentrations above 50 mg l(-1) the relationship between k and suspended solids is non-linear; k also varied with depth. This could be modelled by a single equation, suggesting similarity of response in different cultures. At shallow depths and low suspended solids concentrations k values are variable and hard to measure reliably. The results highlight the need to standardise on a method for the measurement and reporting of k values if these are to be widely applicable in the development of pond models.

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Biodegradation, EnvironmentalBioreactorsChlorophyllEcosystemHalogensLightModels, BiologicalWaste Disposal, FluidWater SupplyComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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S Heaven, C J Banks, E A Zotova. 2005. Light attenuation parameters for waste stabilisation ponds.. https://pubmed.ncbi.nlm.nih.gov/16114677/

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