Light requirements for photosynthesis and growth in several macroalgae from a small soft-water stream in the Spessart Mountains, Germany

Abstract

Abstract Fluence rate-response curves (P vs I curves) were measured in several species of stream macroalgae from laboratory culture and from a small soft-water stream. Photosynthesis of laboratory-grown algae was light saturated at 24 μmol photons m−2 s−1 of white light in Klebsormidium rivulare (Kutzing) Morison et Sheath, at 25.51 μmol m−2 s−1 in Batrachospermum helminthosum Bory emend. Sheath et al., at 35 μmol m−2 s−1 in Balbiania investiens (Lenormand) Sirodot (cultivated at 4 μmol m−2 s−1), at 42 μmol m−2 s−1 in Microspora quadrata Hazen, at 60 μmol m−2 s −1 in Vaucheria bursata (O.F. Muller) C. Agardh (= V. sessilis De Candolle), Stigeoclonium tenue (C. Agardh) Kutzing, Audouinella hermannii (Roth) Duby in De Candolle, Balbiania investiens (cultivated at 40 μmol m −2 s−1) and at 67 μmol m−2 s−1 in Cladophora glomerata (Linnaeus) Kutzing. Photosynthesis of algae taken from the Bieber stream was light saturated at significantly higher photon irradiances of 115 μmol m−2 s−1 in Batrachospermum helminth...