Phytoplankton Biomass and the Hydrodynamic Regime in NEOM, Red Sea

Abstract

NEOM (short for Neo-Mustaqbal) is a $500 billion coastal city megaproject, currently under construction in the northwestern part of the Red Sea, off the coast of Tabuk province in Saudi Arabia, and its success will rely on the preservation of biodiverse marine ecosystems. Monitoring the variability of ecological indicators, such as phytoplankton, in relation to regional environmental conditions, is the foundation for such a goal. We provide a detailed description of the phytoplankton seasonal cycle of surface waters surrounding NEOM using satellite-derived chlorophyll-a (Chl-a) observations, based on a regionally-tuned product of the European Space Agency’s Ocean Colour Climate Change Initiative, at 1 km resolution, from 1997 to 2018. The analysis is also supported with in situ cruise datasets and outputs of a state-of-the-art high-resolution hydrodynamic model. The open waters of NEOM follow the oligotrophic character of the Northern Red Sea (NRS), with a peak during late winter and a minimum during late summer. Coral reef-bound regions, such as Sindala and Sharma, are characterised by higher Chl-a concentrations that peak during late summer. Most of the open waters around NEOM are influenced by the general cyclonic circulation of the NRS and local circulation features, while shallow reef-bound regions are more isolated. Our analysis provides the first description of the phytoplankton seasonality and the oceanographic conditions in NEOM, which may support the development of a regional marine conservation strategy.

A Conceptual Approach to Partitioning a Vertical Profile of Phytoplankton Biomass Into Contributions From Two Communities

“…It hosts one of the longest coral reef systems on Earth (Raitsos et al., 2017). The seasonal cycle of phytoplankton in the northern Red Sea is thought to be driven primarily by nutrient availability (Gittings et al., 2018; Papagiannopoulos et al., 2021). Higher phytoplankton abundance in winter is linked to increased convective mixing, driven by sea‐air heat exchange, that transports nutrients from deeper water into the surface layer (Acker et al., 2008; Papadopoulos et al., 2015; Triantafyllou et al., 2014; Yao et al., 2014).…”

From the shallow to the mesophotic: a characterization of Symbiodiniaceae diversity in the Red Sea NEOM region

“…This supplies cold, nutrient-rich waters at the surface due to thermohaline circulation as well as wind forces (Kheireddine et al, 2021 and references therein). The northern Red Sea is influenced by the general cyclonic circulation observed in this area, as well as the permanent presence of mesoscale features (i.e., cyclonic and anticyclonic eddies) (Kheireddine et al, 2021;Papagiannopoulos et al, 2021). For example, in coastal areas where coral reefs are present, summer phytoplankton bloom can be observed due to local circulation features and the presence of corals that lead to an injection of nutrients within the surface layer (Papagiannopoulos et al, 2021).…”

“…The northern Red Sea is influenced by the general cyclonic circulation observed in this area, as well as the permanent presence of mesoscale features (i.e., cyclonic and anticyclonic eddies) (Kheireddine et al, 2021;Papagiannopoulos et al, 2021). For example, in coastal areas where coral reefs are present, summer phytoplankton bloom can be observed due to local circulation features and the presence of corals that lead to an injection of nutrients within the surface layer (Papagiannopoulos et al, 2021). This region is also characterized by a shallower mixing and a shorter duration of the phytoplankton bloom than in the Gulf of Aqaba (Kheireddine et al, 2021).…”

Physical forcing of phytoplankton dynamics in the Al‐Wajh lagoon (Red Sea)

“…The Red Sea is a marginal sea surrounded by hot arid regions, hosting one of the longest coral reef systems in the world. It extends more than 4000 km along the coastlines, and is thus an important reservoir of marine biodiversity and endemism (Berumen et al 2019;Genevier et al 2019;Papagiannopoulos et al 2021). The coastlines of the Red Sea accommodate more than 50 coastal lagoons (Sultan and Ahmad 1990).…”