@article {5435,
	title = {A simple, user friendly tool to readjust raw PAM data from field measurements to avoid over- or underestimating of microphytobenthos photosynthetic parameters},
	journal = {Journal of Experimental Marine Biology and Ecology},
	volume = {503},
	year = {2018},
	pages = {136-146},
	abstract = {<p class="rtejustify">Intertidal mudflats are among the most productive ecosystems and microphytobenthic (MPB) biofilms play a key role in primary production. MPB primary production varies at short spatial and temporal scales. Accurate measurements thus require rapid non-intrusive methods like pulse amplitude modulate (PAM) fluorescence. However, the effect of granulometry and chl a concentration profile in light attenuation on irradiance and on fluorescence signal in the photic layer need to be taken into account when primary production is estimated using PAM. We propose a tool to readjust raw photosynthetic parameters (rETRmax, α, Ik) estimated from PAM measurements on the field, to avoid over- or underestimation. To develop the tool, we used models previously designed by K{\"u}hl and J{\o}rgensen (1992), Ser{\^o}dio (2004) and Forster and Kromkamp (2004) by integrating the chl a distribution profiles and sediment granulometry from pure sand to pure mud. The sensitivity of the correction to sediment granulometry and the shape of chl a profile were evaluated theoretically using a typical fluorescence data set obtained using PAM measurements. Our results confirm the importance of accounting for both the chl a profile and sediment granulometry when estimating a light attenuation coefficient. We show that, with the same chl a profile, the photosynthetic parameters are more underestimated in mud than in a sandy environment. Thus, granulometry and the chl a profile need to be systematically quantified and used to correct raw data measured in field studies using PAM before estimating photosynthetic parameters. The numerical tool is available as an e-document that is simple and easy to apply to any PAM data.</p>
},
	doi = {https://doi.org/10.1016/j.jembe.2018.02.007},
	url = {https://www.sciencedirect.com/science/article/pii/S0022098117303325},
	author = {Morelle, J{\'e}r{\^o}me and Francis Orvain and Pascal Claquin}
}
