40 results
 Pacific Data Hub

Myora Springs is one of many groundwater discharge sites on North Stradbroke Island (Queensland, Australia). Here spring waters emerge from wetland forests to join Moreton Bay, mixing with seawater over seagrass meadows dominated by eelgrass, Zostera muelleri. We sought to determine how low pH / high CO2 conditions near the spring affect these plants and their interactions with the black rabbitfish (Siganus fuscescens), a co-occurring grazer. In paired-choice feeding trials S. fuscescens preferentially consumed Z. muelleri shoots collected nearest to Myora Springs.

 Pacific Data Hub

Ocean acidification represents a key threat to coral reefs by reducing the calcification rate of the major reef framework builders. In addition, acidification is likely to affect the important relationship between corals and their symbiotic dinoflagellates, and on the productivity of this association. However, little is known about how acidification impacts on the physiology of key reef builders and how acidification interacts with warming.

 Pacific Data Hub

Increasing seawater temperatures and CO2 levels associated with climate change affect the shallow marine ecosystem function. In this study, the effects of elevated seawater temperature and partial pressure of CO2 (pCO2) on subtropical sediment systems of mangrove, seagrass, and coral reef lagoon habitats of Okinawa, Japan, were examined.

 Pacific Data Hub

Increasing atmospheric CO2 can decrease the seawater pH and carbonate ions, which may adversely affect the larval survival of calcareous animals. In this study, we simulated future atmospheric CO2 concentrations (800, 1500, 2000 and 3000 $μ$atm) and examined the effects of ocean acidification on the embryonic and larval stage of an infaunal clam Paphia undulate. Significant decrease of hatching of P.

 Pacific Data Hub

Using the results from the NCAR CSM1.4-coupled global carbon cycle–climate model under the Intergovernmental Panel on Climate Change (IPCC) emission scenarios SRES A2 and B1, we estimated the effects of both global warming and ocean acidification on the future habitats of corals in the seas around Japan during this century. As shown by Yara et al.

 Pacific Data Hub

Skeletal growth records in annually banded massive coral skeletons are an under-exploited archive of coral responses to environmental changes. Average linear extension and calcification rates in Indo-Pacific Porites are linearly related to average water temperatures through 23 to 30¯C. Assessing long-term trends in Porites extension and density requires caution as there is evidence of an age effect whereby in earlier growth years corals will tend to extend less and form a higher density skeleton than in later years. This does not appear to affect calcification rates.

 Pacific Data Hub

Echinoid sea urchins with distributions along the continental shelf and slope of the eastern Pacific often dominate the megafauna community. This occurs despite their exposure to naturally low dissolved oxygen (DO) waters (\textless60 $μ$mol kg−1) associated with the Oxygen Limited Zone and low-pH waters undersaturated with respect to calcium carbonate ($Ømega$CaCO3 \textless 1).

 Pacific Data Hub

In order to help predict the effects of anthropogenic stressors on shallow water carbonate environments, it is important to focus research on regions containing natural oceanographic gradients, particularly with respect to interactions between oceanography and ecologically sensitive carbonate producers. The Galápagos Archipelago, an island chain in the eastern equatorial Pacific, spans a natural nutrient, pH, and temperature gradient due to the interaction of several major ocean currents.

 Pacific Data Hub

The global acidification of the earth's oceans is predicted to impact biodiversity via physiological effects impacting growth, survival, reproduction, and immunology, leading to changes in species abundances and global distributions. However, the degree to which these changes will play out critically depends on the evolutionary rate at which populations will respond to natural selection imposed by ocean acidification, which remains largely unquantified.

 Pacific Data Hub

Summary Synergies among stressors drive unanticipated changes to alternative states, yet little has been done to assess whether alleviating one or more contributing stressors may disrupt these interactions. It would be particularly useful to understand whether the synergistic effects of global and local stressors could be alleviated, leading to slower change or faster recovery, if conditions under the control of local management alone were managed (i.e. nutrient pollution). We utilized field-based mesocosms to manipulate CO2 (i.e.

 Pacific Data Hub

An expedition to the Kavachi submarine volcano (Solomon Islands) in January 2015 was serendipitously timed with a rare lull in volcanic activity that permitted access to the inside of Kavachi's active crater and its flanks. The isolated location of Kavachi and its explosive behavior normally restrict scientific access to the volcano's summit, limiting previous observational efforts to surface imagery and peripheral water-column data.

 Pacific Data Hub

Large and productive fisheries occur in regions experiencing or projected to experience ocean acidification. Anchoveta (Engraulis ringens) constitute the world's largest single-species fishery and live in one of the ocean's highest pCO2 regions. We investigated the relationship of the distribution and abundance of Anchoveta eggs and larvae to natural gradients in pCO2 in the Peruvian upwelling system. Eggs and larvae, zooplankton, and data on temperature, salinity, chlorophyll a and pCO2 were collected during a cruise off Peru in 2013.

 Pacific Data Hub

Ocean acidification (OA) is likely to have an effect on the fertilizing potential of desert dust in high-nutrient, low-chlorophyll oceanic regions, either by modifying iron (Fe) speciation and bioavailability or by altering phytoplankton Fe requirements and acquisition. To address this issue, short incubations (4 days) of northeast subarctic Pacific waters enriched with either FeSO4 or dust and set at pH 8.0 (in situ) and 7.8 were conducted in August 2010.

 Pacific Data Hub

Variation in rates of herbivory may be driven by direct effects of the abiotic environment on grazers, as well as indirect effects mediated by their food. Disentangling these direct and indirect effects is of fundamental importance for ecological forecasts of changing climate on species interactions and their influence on biogenic habitat. Whilst elevated atmospheric CO2 may have direct effects on grazers with calcareous structures via ‘ocean acidification', it may also have indirect effects via changes caused to their food.

 Pacific Data Hub

Ocean acidification and greenhouse warming will interactively influence competitive success of key phytoplankton groups such as diatoms, but how long-term responses to global change will affect community structure is unknown. We incubated a mixed natural diatom community from coastal New Zealand waters in a short-term (two-week) incubation experiment using a factorial matrix of warming and/or elevated pCO2 and measured effects on community structure.

 Pacific Data Hub

Alterations in predation pressure can have large effects on trophically-structured systems. Modification of predator behaviour via ocean warming has been assessed by laboratory experimentation and metabolic theory. However, the influence of ocean acidification with ocean warming remains largely unexplored for mesopredators, including experimental assessments that incorporate key components of the assemblages in which animals naturally live.

 Pacific Data Hub

Oceanic uptake of anthropogenic carbon dioxide results in a decrease in seawater pH, a process known as “ocean acidification”. The pearl oyster Pinctada fucata, the noble scallop Chlamys nobilis, and the green-lipped mussel Perna viridis are species of economic and ecological importance along the southern coast of China. We evaluated the effects of seawater acidification on clearance, respiration, and excretion rates in these three species. The ammals were reared in seawater at pH 8.1 (control), 7.7, or 7.4. The clearance rate was highest at pH 7.7 for P. fucata and at pH 8.1 for C.

 Pacific Data Hub

There is increasing concern about the effects of ocean acidification on marine biogeochemical and ecological processes and the organisms that drive them, including marine bacteria. Here, we examine the effects of elevated CO2 on the bacterioplankton community during a mesocosm experiment using an artificial phytoplankton community in subtropical, eutrophic coastal waters of Xiamen, southern China.

 Pacific Data Hub

Rising anthropogenic CO2 in the atmosphere is accompanied by an increase in oceanic CO2 and a concomitant decline in seawater pH (ref. 1). This phenomenon, known as ocean acidification (OA), has been experimentally shown to impact the biology and ecology of numerous animals and plants, most notably those that precipitate calcium carbonate skeletons, such as reef-building corals. Volcanically acidified water at Maug, Commonwealth of the Northern Mariana Islands (CNMI) is equivalent to near-future predictions for what coral reef ecosystems will experience worldwide due to OA.

 Pacific Data Hub

Increasing atmospheric CO2 concentrations are causing decreased pH over vast expanses of the ocean. This decreasing pH may alter biogeochemical cycling of carbon and nitrogen via the microbial process of nitrification, a key process that couples these cycles in the ocean, but which is often sensitive to acidic conditions. Recent reports have indicated a decrease in oceanic nitrification rates under experimentally lowered pH. How the composition and abundance of ammonia-oxidizing bacteria (AOB) and archaea (AOA) assemblages respond to decreasing oceanic pH is unknown.