Ecosystem services provided by marine and freshwater phytoplankton

Abstract

Phytoplankton, the ecological group of microalgae adapted to live in apparent suspension in water masses, is much more than an ecosystem’s engineer. In this opinion paper, we use our experience as phytoplankton ecologists to list and highlight the services provided by phytoplankton, trying to demonstrate how their activity is fundamental to regulate and sustain Life on our Planet. Although the number of services produced by phytoplankton can be considered less numerous than that produced by other photosynthetic organisms, the ubiquity of this group of organisms, and their thriving across oceanic ecosystems make it one of the biological engines moving our biosphere. Supporting services provided by phytoplankton include almost half of the global primary and oxygen production. In addition, phytoplankton greatly pushes biogeochemical cycles and nutrient (re)cycling, not only in aquatic ecosystems but also in terrestrial ones. In addition, it significantly contributes to climate regulation (regulating services), supplies food, fuels, active ingredients and drugs, and genetic resources (provisioning services), has inspired artistic and craft works, mythology, and, of course, science (cultural services), and much more. Therefore, phytoplankton should be considered in all respects a true biosphere’s engineer.

Contribution of silica-scaled chrysophytes to ecosystems services: a review

“…Many silica-scaled chrysophytes are alternatively photoautotrophic, mixotrophic or heterotrophic (Table 1), whilst only Mallomonas, Neotessella and Synura are considered to be strict photoautotrophs (Andersen, 1987;Bhatti & Colman, 2005). The photosynthetic activity of phytoplankton has significant contribution to the global net primary production and atmospheric oxygen (reviewed by Naselli-Flores & Padisák, 2022). In comparison with the photosynthetic rate of the total phytoplankton communities (920-1866 µmol O 2 mg Chl −1 h −1 or 45-1575 µmol C mg Chl -1 h -1 , Martínez, 1980;Vincent, 1983;Williams et al, 1983;Guildford et al, 2007), photoautotrophic silica-scaled chrysophytes alone can have significant photosynthetic evolution rate (see examples in Table 3).…”

“…Phytoplankton is known to contribute significantly to the absorption of global annual CO 2 emission (about 20-35%, Khatiwala et al, 2009;Naselli-Flores & Padisák, 2022). Autotrophic silica-scaled chrysophytes have special physiological characteristics, such as lacking CO 2 concentrating mechanisms (CCM) and external carbonic anhydrase (CA).…”

Comparing Spatio-Temporal Dynamics of Functional and Taxonomic Diversity of Phytoplankton Community in Tropical Cascading Reservoirs

“…It is well known that phytoplankton is essential for some aquatic ecosystem functions like carbon uptake and primary production (Lewis, 2011;Naselli-Flores and Padisák, 2022). Functional traits namely size, cell arrangement, mixotrophy, presence of silica provide answers about the individual performance of species, likewise it provides information about population dynamics, community response mechanisms to changes in environmental conditions and trophic interactions.…”

Functional dynamics of phytoplankton assemblages in hypertrophic lakes: Functional- and species diversity is highly resistant to cyanobacterial blooms

“…Small shallow lakes are numerous (35 million shallow lakes < 0.001 km 2 ; Meybeck, 1995) and provide highly diverse habitats (they can be e.g., small ponds with adjacent wetlands, pit lakes, oxbow lakes, sweet-water reservoirs). They can act as refugees and "steppingstones" for freshwater biota in heavily transformed landscapes, and they play a pivotal role in local biogeochemical cycles and water retention (Naselli-Flores and Padisák, 2022).…”