Download or read book The Combined Effects of Ocean Acidification with Water Flow and Temperature on Tropical Non calcareous Macroalgae written by Maureen Ho and published by . This book was released on 2016 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: The vulnerability of coral reefs has substantially increased in the past few decades due to accelerating human-driven global change. The effects of ocean acidification (OA) and global warming individually and interactively have resulted in varying degrees of responses in benthic reef organisms. For non-calcareous macroalgae, the physiological and ecological responses to physical environmental changes can alter their relative abundances, which are often used as an indicator of the overall coral reef status. To better understand how fleshy macroalgae will respond to various physical parameters, three separate experiments were conducted from June 2014 to July 2015 in Moorea, French Polynesia. An important physical driver in transferring nutrients and dissolved gases to benthic reef organisms is water motion. In 2014, I tested the hypothesis that increased water motion and elevated pCO2 would benefit Amansia rhodantha (a CO2 user) more than Dictyota bartayresiana and Lobophora variegata (HCO3- users). The highest and lowest growth rates were at the intermediate and highest flow speed, respectively, for all three species. A. rhodantha exhibited the greatest reduction in biomass at reduced flow under ambient pCO2, indicating high sensitivity to mass transfer and carbon limitation. In 2015, the interactive effects of temperature and OA were tested in a two-part study on the metabolic (i.e. photosynthesis and respiration) and growth responses of D. bartayresiana and A. rhodantha. The first study in January 2015 showed that net photosynthesis in both species was affected by high pCO2 but not temperature, and the combination of temperature and OA affected respiration rates. In the second study in July 2015, metabolic rates were affected by temperature but not pCO2. Net photosynthesis and respiration of A. rhodantha were highest under OA conditions at 27.5 oC, but were reduced at 30 oC. There was no effect on metabolic rates of D. bartayresiana across all temperature treatments. The relative growth rates for D. bartayresiana were higher than A. rhodantha in the first study, while both species exhibited varying responses to treatments in the second study. Lastly, from May to June 2015, massive Porites spp. was paired with D. bartayresiana in competitive interactions at low and high flow speeds under ambient and elevated pCO2 levels. I tested the hypothesis that increased water flow would increase algal growth rates, enhancing the competitive ability of the alga against the coral. For corals, I predicted that OA and reduced water flow would negatively affect the corals, thus increasing susceptibility to algal overgrowth. Net calcification and the photosynthetic efficiency of corals were used as a proxy for fitness and health status, respectively, however neither was affected by water flow or OA. On the contrary, growth rates of D. bartayresiana were significantly reduced under low flow. The negative effects of reduced water motion on macroalgae may potentially compromise the ability of the alga to compete. The variation in water motion can affect resource acquisition and when combined with OA, can have significant implications on species interactions. These results indicate the importance of water motion in influencing macroalgal growth and provide insights to the varying responses in fleshy macroalgae to global change. Furthermore, their physiological responses may be attributed to their different carbon uptake strategies, as A. rhodantha was more sensitive to reduced flow and temperature than D. bartayresiana.
Download or read book The Combined Effects of Ocean Acidification with Morphology Water Flow and Algal Acclimation on Metabolic Rates of Tropical Coralline Algae written by Sarah Merolla and published by . This book was released on 2017 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt: Coral reefs are currently facing multiple stressors that threaten their health and function, including ocean acidification (OA). OA has been shown to negatively affect many reef calcifiers, such as coralline algae that provide many critical contributions to reef systems. Past studies have focused on how OA independently influences coralline algae, but more research is necessary as it is expected that the effects of OA on coralline algae will vary depending on many other factors. To better understand how algal morphology, water flow, and algal acclimation interact with OA to affect coralline algae, three studies were conducted in Moorea, French Polynesia, from June 2015 to July 2016. In January 2016, I tested the hypothesis that algal individuals with higher morphological complexity would exhibit faster metabolic rates under ambient pCO2 conditions, but would also demonstrate higher sensitivity to OA conditions. For three species of crustose coralline algae, Lithophyllum kotschyanum, Neogoniolithon frutescens, and Hydrolithon reinboldii, algal individuals with more complex morphologies demonstrated faster rates of calcification, photosynthesis, and respiration in the ambient pCO2 treatment than individuals with simpler morphological forms. There also appeared to be a relationship between morphology and sensitivity to OA conditions, with calcification rates negatively correlated with higher morphological complexity. In the summers of 2015 and 2016, I conducted three experiments examining the effects of water flow and OA on different morphologies of coralline algae to test the hypotheses that increased flow would enhance metabolic rates and mitigate the effects of OA, and that algae with more complex morphologies would be more responsive to increased water flow and more sensitive to OA conditions. A field experiment investigating the effects of water flow on Amphiroa fragilissima, L. kotschyanum, N. frutescens, and H. reinboldii detected enhanced rates of calcification, photosynthesis, and respiration with increased flow, and this relationship appeared to be the strongest for the crustose algal species with the highest structural complexity. A flume manipulation examining the combined effects of water flow and OA on A. fragilissima, L. kotschyanum, N. frutescens, H. reinboldii, and Porolithon onkodes suggested that coralline algal species with high structural complexity were the most sensitive to OA conditions. Finally, A. fragilissima and L. kotschyanum were maintained in different pCO2 and water flow conditions in a long-term mesocosm experiment, which indicated that flow was unable to mitigate the effects of OA on coralline algae. In the summer of 2016, I investigated the acclimation potential of A. fragilissima and L. kotschyanum to OA, and predicted that the original treatment conditions would induce phenotypic modifications that would influence algal responses to the end treatment. There were negative effects of long-term exposure of coralline algae to elevated pCO2 conditions on calcification and photosynthesis, though partial acclimation in calcification to OA was observed. The instantaneous exposure of elevated pCO2 had negative impacts on algal calcification, but had a nominal effect on photosynthesis. No effects of long-term or instantaneous exposure to elevated pCO2 were observed for respiration. The results of these studies indicate that the coralline algal response to OA conditions will likely be complex and depend on numerous factors including water flow, morphology, and acclimation potential. Therefore, it is critical that future studies further investigate the effects of these factors; specifically examining the mechanisms that underlie these responses in order to better predict the future of coralline algae and thus coral reef ecosystems in a more acidic ocean.
Download or read book The Combined Effects of Ocean Acidification with Fleshy Macroalgae and Filamentous Turfs on Tropical Crustose Coralline Algae written by Lansing Yun Perng and published by . This book was released on 2019 with total page 111 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ocean Acidification written by National Research Council and published by National Academies Press. This book was released on 2010-09-14 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ocean has absorbed a significant portion of all human-made carbon dioxide emissions. This benefits human society by moderating the rate of climate change, but also causes unprecedented changes to ocean chemistry. Carbon dioxide taken up by the ocean decreases the pH of the water and leads to a suite of chemical changes collectively known as ocean acidification. The long term consequences of ocean acidification are not known, but are expected to result in changes to many ecosystems and the services they provide to society. Ocean Acidification: A National Strategy to Meet the Challenges of a Changing Ocean reviews the current state of knowledge, explores gaps in understanding, and identifies several key findings. Like climate change, ocean acidification is a growing global problem that will intensify with continued CO2 emissions and has the potential to change marine ecosystems and affect benefits to society. The federal government has taken positive initial steps by developing a national ocean acidification program, but more information is needed to fully understand and address the threat that ocean acidification may pose to marine ecosystems and the services they provide. In addition, a global observation network of chemical and biological sensors is needed to monitor changes in ocean conditions attributable to acidification.
Download or read book Ocean Acidification Effects on Photosynthesis in Tropical Marine Macroalgae written by Regina C. Zweng and published by . This book was released on 2017 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt: Field data from CO2 vents, a current model of future ocean acidification conditions, show a positive correlation between elevated seawater pCO2 and fleshy macroalgal abundance, as well as a negative correlation between elevated seawater pCO2 and calcareous macroalgal abundance on coral reefs. One underlying physiological mechanism for increases of fleshy macroalgae species in response to greater pCO2 could be an increase in their photosynthesis. Furthermore, inorganic carbon use mechanisms, irradiance and depth may influence species-specific responses to ocean acidification. Therefore, this thesis aimed to discern carbon use strategies and photosynthetic responses to elevated pCO2 of dominant tropical fleshy and calcareous macroalgae. All species studied were able to utilize HCO3 - for photosynthesis. 33% of calcifying macroalgae and 80% of fleshy macroalgae had increased photosynthetic rates in response to lower pH. Thus, future conditions of OA may perpetuate or exacerbate the abundance of fleshy seaweeds at the expense of calcareous species.
Download or read book Physiology of Echinodermata written by Richard A. Boolootian and published by . This book was released on 1966 with total page 848 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Marine Animal Forests written by Sergio Rossi and published by Springer. This book was released on 2017-08-15 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the last decades there has been an increasing evidence of drastic changes in marine ecosystems due to human-induced impacts, especially on benthic ecosystems. The so called “animal forests” are currently showing a dramatic loss of biomass and biodiversity all over the world. These communities are dominated by sessile suspension feeder organisms (such as sponges, corals, gorgonians, bivalves, etc.) that generate three-dimensional structures, similar to the trees in the terrestrial forest. The animal forest provide several ecosystem services such as food, protection and nursery to the associated fauna, playing an important role in the local hydrodynamic and biogeochemical cycles near the sea floor and acting also as carbon sinks. The present book focus its attention on these three dimensional animal structures including, for the first time, all the different types of animal forests of the world in a single volume.
Download or read book Climate Change Ocean Acidification and Sponges written by José Luis Carballo and published by Springer. This book was released on 2017-10-27 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt: While sponges represent a very simple group of organisms, which are represented by over 8000 species, there is considerable interest in the increasing role they may play in future marine ecosystems. While we still have a comparatively limited understanding of how sponges will respond to ocean warming and acidification there is evidence that some species may have the ability to acclimate or even adapt to these stressors. This comprehensive collection of articles describes our current understanding of the impacts of ocean acidification and warming on sponges across multiple levels of biological organisation, and from the geological past to the present. With expert contributions from across the world this book represents the most up-to-date view on sponge responses to climate change. This book will be of interest to a wide audience of marine scientists and managers, who are grappling with how to manage, conserve and protect marine ecosystems.
Download or read book Coralline Algae Globally Distributed Ecosystem Engineers written by Laurie Carol Hofmann and published by Frontiers Media SA. This book was released on 2020-07-08 with total page 159 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ocean Acidification written by Jean-Pierre Gattuso and published by Oxford University Press. This book was released on 2011-09-15 with total page 347 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ocean helps moderate climate change thanks to its considerable capacity to store CO2, through the combined actions of ocean physics, chemistry, and biology. This storage capacity limits the amount of human-released CO2 remaining in the atmosphere. As CO2 reacts with seawater, it generates dramatic changes in carbonate chemistry, including decreases in pH and carbonate ions and an increase in bicarbonate ions. The consequences of this overall process, known as "ocean acidification", are raising concerns for the biological, ecological, and biogeochemical health of the world's oceans, as well as for the potential societal implications. This research level text is the first to synthesize the very latest understanding of the consequences of ocean acidification, with the intention of informing both future research agendas and marine management policy. A prestigious list of authors has been assembled, among them the coordinators of major national and international projects on ocean acidification.
Download or read book Bridging the gap between ocean acidification impacts and economic valuation written by International Union for the Conservation of Nature and Natural Resources (IUCN). Global Marine and Polar Programme. and published by IUCN. This book was released on 2015-05-01 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt: Following the first international workshop on the economics of ocean acidification organized by the Centre Scientifique de Monaco and the International Atomic Energy Agency in 2010, a second international workshop was held in November 2012, which explored the level of risk, and the resilience or vulnerability of defined regions of the world ocean in terms of fishery and aquaculture species and economic impacts, and social adaptation. This report includes the findings and recommendations of the respective regional working groups and is the result of an interdisciplinary survey of ocean acidification-sensitive fisheries and aquaculture.
Download or read book Stressors in the Marine Environment written by Martin Solan and published by Oxford University Press. This book was released on 2016-03-10 with total page 471 pages. Available in PDF, EPUB and Kindle. Book excerpt: A multitude of direct and indirect human influences have significantly altered the environmental conditions, composition, and diversity of marine communities. However, understanding and predicting the combined impacts of single and multiple stressors is particularly challenging because observed ecological feedbacks are underpinned by a number of physiological and behavioural responses that reflect stressor type, severity, and timing. Furthermore, integration between the traditional domains of physiology and ecology tends to be fragmented and focused towards the effects of a specific stressor or set of circumstances. This novel volume summarises the latest research in the physiological and ecological responses of marine species to a comprehensive range of marine stressors, including chemical and noise pollution, ocean acidification, hypoxia, UV radiation, thermal and salinity stress before providing a perspective on future outcomes for some of the most pressing environmental issues facing society today. Stressors in the Marine Environment synthesises the combined expertise of a range of international researchers, providing a truly interdisciplinary and accessible summary of the field. It is essential reading for graduate students as well as professional researchers in environmental physiology, ecology, marine biology, conservation biology, and marine resource management. It will also be of particular relevance and use to the regulatory agencies and authorities tasked with managing the marine environment, including social scientists and environmental economists.
Download or read book Guide to Best Practices for Ocean Acidification Research and Data Reporting written by and published by . This book was released on 2011 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effects of Ocean Acidification on Marine Non calcifying Macroalgae written by Mark Olischläger and published by . This book was released on 2012 with total page 221 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Understanding Individual and Combined Effects of Ocean Acidification Coastal Runoff and Warming on Marine Calcifying Organisms on Tropical Coral Reefs written by Nikolas Vogel and published by . This book was released on 2015 with total page 187 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Combined Effect of Ocean Acidification and Euthrophication on Water PH and Aragonite Saturation State in the Northern Gulf of Mexico written by Fenix Garcia Tigreros and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Rising atmospheric carbon dioxide (CO2) concentrations are increasing the rate at which anthropogenic CO2 is accumulating in the ocean, and thereby acidifying ocean water. However, accumulation of anthropogenic CO2 is not the only process affecting coastal oceans. Anthropogenic inputs of nutrients to coastal waters can result in massive algal blooms, a process known as eutrophication. Microbial consumption of this organic matter depletes bottom waters of oxygen and increases acidity through the release of CO2. This study assesses the synergistic effect of ocean acidification and eutrophication in the coastal ocean using data from six cruises to the northern Gulf of Mexico. In addition, this study investigates the effect of the 2011 Mississippi River flood on coastal pH and aragonite saturation states. Data from a model simulation using data collected from the northern Gulf of Mexico indicates that eutrophication is contributing to acidification of subsurface waters and plays a larger role than acidification from atmospheric CO2 uptake. Furthermore, results from the model simulation show that the decrease in pH since the industrial era is 0.04 units greater than expected from ocean acidification and eutrophication combined. The additional decrease was attributed to the reduced buffering capacity of the region and may be related to the uptake of atmospheric CO2 into O2-depleted and CO2-enriched waters, the addition of atmospheric CO2 into O2-rich and CO2-poor waters, the input of CO2 via respiration into waters in equilibrium with high atmospheric CO2, or a combination of all three processes. The electronic version of this dissertation is accessible from http://hdl.handle.net/1969.1/149421
Download or read book Impacts of Ocean Acidification on Coralline Algae written by Chenchen Shen and published by . This book was released on 2017 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: Oceanic uptake of rising anthropogenic CO2 emissions has caused the emergence of ocean acidification as a major threat to marine ecosystems worldwide. Along eastern boundary current systems, seawater is naturally acidified due to coastal upwelling of low pH seawater from depth. Compounded by ocean acidification, upwelling regions are expected to become increasingly corrosive to calcifying organisms, potentially forcing them beyond their physiological tolerance windows. In my dissertation, I focused on the impacts of ocean acidification on calcareous coralline algae in the California Current System. Using coralline algae in rocky intertidal habitats as model organisms, I extend the implications of ocean acidification from the organismal level to the broader community level. Global environmental change implies not only gradual changes in the mean values of environmental variables but also an increase in variability and the likelihood of rare, extreme events. In Chapter 2, I conducted a laboratory experiment to explore potential interactions between two different types of environmental stressors. Specifically, I tested the effects of elevated pCO2, including variable pCO2 treatments, and a severe desiccation event on the coralline species, Corallina vancouveriensis. I found that C. vancouveriensis growth was negatively impacted by both elevated pCO2 and desiccation stress, although their combined effects were approximately additive rather than synergistic. Furthermore, while high pCO2 at constant levels only caused small reductions in algal growth over a two-week period, these effects were exacerbated by pCO2 variability. One criticism of laboratory experiments testing species responses to environmental change is that they isolate organisms under simplified conditions. The potential of overlooking important biotic or abiotic factors present in the natural environment limits the inferences that can be made from laboratory studies. In Chapter 3, I conducted a reciprocal removal experiment at two field sites and two wave exposures to investigate potential changes in the interactions between coralline and fleshy turf-forming algae since the 1980s. I used as a baseline the results from a similar study conducted nearly 30 years ago that failed to detect spatial competition between coralline and fleshy algae. Despite the progression of ocean acidification over the last three decades, my results indicated that the lack of competition between coralline and fleshy algae persists to this day, with results consistent across both sites and wave exposures. The findings in Chapter 3 refer to present-day interactions, but in the future, ocean acidification is expected to be detrimental to coralline algae while potentially benefitting fleshy algae. Both coralline and fleshy algae form turf habitats that shelter diverse epifaunal communities. Thus, changes in the algal composition of turf habitats may lead to broader changes encompassing epifaunal communities, depending on the degree of specialization displayed in epifaunal habitat associations. In Chapter 4, I compared the abundance, richness, and community composition of epifauna between coralline and fleshy turf habitats at four sites along the Oregon-California coast. I found that epifauna were more abundant in coralline turfs due to higher turf density. However, epifaunal richness and community composition were similar between turf types, indicating high levels of redundancy in habitat provision between coralline and fleshy algae. Since most species of epifauna tended to be turf generalists, they may be resistant to the potential indirect effects of ocean acidification involving declines in coralline turf habitat. My dissertation combined a variety of standard ecological methodologies to help translate ocean acidification impacts from the organismal level to the community level. Overall, while I found that elevated pCO2 decreased coralline growth in the laboratory, evidence from the field suggested a capacity for communities to resist the effects of ocean acidification and remain resilient. In the natural environment, ocean acidification impacts may be moderated by multiple environmental variables working in different directions, the temporal dynamics of stressors allowing for periods of recovery, and species interactions having dampening effects. One way forward to unite theories of change with those of resistance is to identify ecosystem indicators and critical thresholds that may help provide a more comprehensive view of ecosystem functioning and stability in the face of global change.
