Selecting the Most Sustainable Phosphorus Adsorbent for Lake Restoration: Effects on the Photosynthetic Activity of Chlorella sp. Álvarez-Manzaneda Salcedo, María Inmaculada Castaño Hidalgo, Álvaro Vicente Álvarez De Manzaneda, María Inmaculada De This work was supported by PID2021-122429OB-I00 project, TED2021-129384B-C21 and TED2021-129384B-C22 projects funded MCIN/AEI/10.13039/501100011033 and European Union NextGeneration EU/PRTR. This work was also supported by the European Commission (H2020-MSCA-IF-2019, Grant no. 897535). To promote the conservation of aquatic ecosystems, it is essential to delve into restoration techniques for selecting the most sustainable option for combating eutrophication. Hence, we study the effects of novel phosphorus (P) adsorbents (magnetic carbonyl iron particles, HQ, and two non-magnetic P adsorbents: CFH-12® and Phoslock®) on the growth and photosynthetic activity of Chlorella sp. More specifically, the intrinsic photochemical efficiency of PSII (ΦPSII) and the nonphotochemical quenching (NPQ) were measured in Chlorella sp. after different contact times with different concentrations of these adsorbents. Our initial hypothesis was that non-magnetic P adsorbents have more effects on the organisms than magnetic ones. However, our results did not show strong evidence of inhibitory effects caused by HQ nor CFH-12® (no significant effect size on ΦPSII), while Phoslock® showed inhibitory effects on the photosynthetic activity of Chlorella sp. for any of its concentrations (NPQ = 0). Lastly, we compared the effect of the studied P adsorbents in a real application scenery (Honda wetland, Spain). For this study case, it is likely that CFH-12® and HQ doses would not cause any negative effects on photosynthetic efficiency while Phoslock®, by limiting light availability, will drastically reduce it. 2024-11-07T12:34:50Z 2024-11-07T12:34:50Z 2024-09-24 journal article Álvarez-Manzaneda, I.; Castaño-Hidalgo, Á.; de Vicente, I. Selecting the Most Sustainable Phosphorus Adsorbent for Lake Restoration: Effects on the Photosynthetic Activity of Chlorella sp. Sustainability 2024, 16, 8305. https://doi.org/10.3390/su16198305 https://hdl.handle.net/10481/96753 10.3390/su16198305 eng info:eu-repo/grantAgreement/EC/H2020/897535 http://creativecommons.org/licenses/by-nc-nd/3.0/ open access Creative Commons Attribution-NonCommercial-NoDerivs 3.0 License MDPI