Periodic Reporting for period 2 - Mesophotic (Past and present mesophotic coral ecosystems as a predictor for survival of coral reefs in an era of climate change)
Período documentado: 2020-10-01 hasta 2021-09-30
Mesophotic Coral Ecosystems (MCEs) are characterized by the presence of light-dependent corals and associated communities, found at depths ranging from 30 m to 150 m in tropical and subtropical regions. These communities create massive reef structures with diverse but characteristic morphologies and geochemical signatures. In many localities around the world, MCEs are linked physically, and possibly also biologically, to their shallow-water reef counterparts. Therefore, they have the potential to act as refugia for shallow reefs with a source of propagules, contributing to the resilience of shallower coral reefs. However, recently, the new discoveries of MCE communities question the assumption that reef corals equate with shallow water, mainly because MCEs extend depth ranges of many corals.
In this study, I have been investigating the modern and ancient MCEs to compare the biodiversity, community composition and geochemical properties of shallow reefs and MCEs. In addition, I developed methods to study these challenging environments and understand the spatial and vertical distribution of modern MCEs. The main goal was to discover community structure dynamics over space and time for improved prediction of the Deep Reef Refugia Hypothesis (DRRH) in an era of global climate change. The uniqueness and advantages of this study are largely achieved due to the combination of technology, geology, ecology, and molecular approaches. Furthermore, presenting those results to the public via conferences, social media and press releases encourage acting of the public to favour these unexplored and understudied ecosystems.
The combination of the studies conducted in this project provides a major step forward towards recognizing selection forces that are shaping coral population structure and through this understanding the potential of MCEs in serving as “lifeboats” for the world’s coral reefs. Management decisions and conservation efforts could be done only with enough baseline knowledge which does not exist in the case of mesophotic ecosystems, hence the overall objective of this project was to gain new knowledge and methodologies for the benefit of exploring and conserving the mesophotic ecosystems.
In this study, I have been investigating the modern and ancient MCEs to compare the biodiversity, community composition and geochemical properties of shallow reefs and MCEs. In addition, I developed methods to study these challenging environments and understand the spatial and vertical distribution of modern MCEs. The main goal was to discover community structure dynamics over space and time for improved prediction of the Deep Reef Refugia Hypothesis (DRRH) in an era of global climate change. The uniqueness and advantages of this study are largely achieved due to the combination of technology, geology, ecology, and molecular approaches. Furthermore, presenting those results to the public via conferences, social media and press releases encourage acting of the public to favour these unexplored and understudied ecosystems.
The combination of the studies conducted in this project provides a major step forward towards recognizing selection forces that are shaping coral population structure and through this understanding the potential of MCEs in serving as “lifeboats” for the world’s coral reefs. Management decisions and conservation efforts could be done only with enough baseline knowledge which does not exist in the case of mesophotic ecosystems, hence the overall objective of this project was to gain new knowledge and methodologies for the benefit of exploring and conserving the mesophotic ecosystems.
Over the last four years, I have been working and studying at The University of Queensland, Australia and Bar Ilan University, Israel, for the outgoing and incoming phases of the study, respectively. I have participated in several developmental workshops and presented the results of this study at a few international conferences and several seminars. I have published 21 scientific peer-reviewed papers and two scientific peer-reviewed book chapters as part of my role in the project and in all cases, the action got the appropriate needed mention. I have developed a website specifically for the project which is updated regularly with new publications or events (https://mceisrael.wixsite.com/796025). In addition, the results and findings of this project are shared in social media (e.g. @mceisrael on Twitter, Israel Mesophotic Reefs on Facebook) and on public events and media press. In the period until today, I have conducted four expeditions to the Great Barrier Reef and Moreton Bay reefs to work on a wide range of coral reefs, the results of these expeditions are yet to be published fully but hopefully will be published soon. Additionally, I had a successful visit to the Museum of Tropical Queensland at Townsville to get samples of mesophotic corals, which were used for testing our ability to accurately date mesophotic corals using the high-persistent U-series dating developed at The University of Queensland. The trials on those samples were highly successful and encouraged us to hopefully conduct more sampling soon.
Major findings from this project are the ability to predict the depth distribution of different communities based on the light availability in the specific region and the impact of the recent year's anthropogenic heat stress specifically on MCEs. The light availability modelling findings enable us to predict community composition along the depth gradient globally and expand the scope of the project to regions we were not targeted at the beginning of the project. Furthermore, historical ecology practices provide me with tools to reconstruct past communities and predict future trends of degradation in these communities, based on the forecasted climate change impacts, specifically to MCEs. With this knowledge, we conducted two case studies, first on the modern distribution of mesophotic communities in the region of the Eastern Tropical Pacific, along a wide depth/light gradient. Second, we dive deep into the mesophotic ecosystems of the Red Sea and provide past and modern data that explain the immense degradation of those ecosystems over the last decade. We hope that our findings will be used to implement management and conservation plans to enable mesophotic communities to recover and flourish in this era of global change and other anthropogenic disturbances.
Major findings from this project are the ability to predict the depth distribution of different communities based on the light availability in the specific region and the impact of the recent year's anthropogenic heat stress specifically on MCEs. The light availability modelling findings enable us to predict community composition along the depth gradient globally and expand the scope of the project to regions we were not targeted at the beginning of the project. Furthermore, historical ecology practices provide me with tools to reconstruct past communities and predict future trends of degradation in these communities, based on the forecasted climate change impacts, specifically to MCEs. With this knowledge, we conducted two case studies, first on the modern distribution of mesophotic communities in the region of the Eastern Tropical Pacific, along a wide depth/light gradient. Second, we dive deep into the mesophotic ecosystems of the Red Sea and provide past and modern data that explain the immense degradation of those ecosystems over the last decade. We hope that our findings will be used to implement management and conservation plans to enable mesophotic communities to recover and flourish in this era of global change and other anthropogenic disturbances.
The impact of the results and further implications of the project provide a tool for identifying regional mesophotic reefs, as well as for understanding regional benthic cover characteristics and potential contributions to past and future geomorphology. This project characterises the spatial distribution of benthic communities and associated benthic cover over time and space. Furthermore, establishes a baseline for ecological productivity at mesophotic depths, and provides a baseline for studies ranging from regional distribution to future risk assessment of increasing anthropogenic stressors along with all coral reef ecosystems (e.g. global warming, pollution, power and desalination plants, increased coastal development, etc.…).
The focus and implementation of this project build a baseline for future mesophotic ecosystems research and conservation decisions for the benefit of coral reefs around the world and the human society depends on them.
The focus and implementation of this project build a baseline for future mesophotic ecosystems research and conservation decisions for the benefit of coral reefs around the world and the human society depends on them.