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Surface water methane (CH4) and nitrous oxide (N2O) concentrations and fluxes were investigated in two subtropical coastal embayments (Bramble Bay and Deception Bay, which are part of the greater Moreton Bay, Australia). Measurements were done at 23 stations in seven campaigns covering different seasons during 2010-2012. Water-air fluxes were estimated using the Thin Boundary Layer approach with a combination of wind and currents-based models for the estimation of the gas transfer velocities. The two bays were strong sources of both CH4 and N2O with no significant differences in the degree of saturation of both gases between them during all measurement campaigns. Both CH4 and N2O concentrations had strong temporal but minimal spatial variability in both bays. During the seven seasons, CH4 varied between 500% and 4000% saturation while N2O varied between 128 and 255% in the two bays. Average seasonal CH4 fluxes for the two bays varied between 0.5±0.2 and 6.0±1.5 mg CH4/m**2/day while N2O varied between 0.4±0.1 and 1.6±0.6 mg N2O/m**2/day. Weighted emissions (t CO2-e) were 63%-90% N2O dominated implying that a reduction in N2O inputs and/or nitrogen availability in the bays may significantly reduce the bays' greenhouse gas (GHG) budget. Emissions data for tropical and subtropical systems is still scarce. This work found subtropical bays to be significant aquatic sources of both CH4 and N2O and puts the estimated fluxes into the global context with measurements done from other climatic regions.

An experiment was conceived in which we monitored degradation of GlcDGD. Independent of the fate of the [14C]glucosyl headgroup after hydrolysis from the glycerol backbone, the 14C enters the aqueous or gas phase whereas the intact lipid is insoluble and remains in the sediment phase. Total degradation of GlcDGD then is obtained by combining the increase of radioactivity in the aqueous and gaseous phases. We chose two different sediment to perform this experiment. One is from microbially actie surface sediment sampled in February 2010 from the upper tidal flat of the German Wadden Sea near Wremen (53° 38' 0N, 8° 29' 30E). The other one is deep subsurface sediments recovered from northern Cascadia Margin during Integrated Ocean Drilling Program Expedition 311 [site U1326, 138.2 meters below seafloor (mbsf), in situ temperature 20 °C, water depth 1,828 m. We performed both alive and killed control experiments for comparison. Surface and subsurface sediment slurry were incubated in the dark at in situ temperature, 4 °C and 20 °C for 300 d, respectively. The sterilized slurry was stored at 20 °C. All incubations were carried out under N2 headspace to ensure anaerobic conditions. The sampling frequency was high during the first half-month, i.e., after 1, 2, 7, and 14 d; thereafter, the sediment slurry was sampled every 2 months. At each time point, samples were taken in triplicate for radioactivity measurements. After 300 d of incubation, no significant changes of radioactivity in the aqueous phase were detected. This may be the result of either the rapid turnover of released [14C] glucose or the relatively high limit of detection caused by the slight solubility (equivalent to 2% of initial radioactivity) of GlcDGD in water. Therefore, total degradation of GlcDGD in the dataset was calculated by combining radioactivity of DIC, CH4, and CO2, leading to a minimum estimate.

The main goal of this study was to evaluate short-term interactions between increased CO2, UVR and inorganic macronutrients (N, P and Si) on summer phytoplankton assemblages in the Ria Formosa coastal lagoon (SW Iberia), subjected to intense anthropogenic pressures and highly vulnerable to climate change. A multifactorial experiment using 20 different nutrient-enriched microcosms exposed to different spectral and CO2 conditions was designed. Before and after a 24-h in situ incubation, phytoplankton abundance and composition were analysed. Impacts and interactive effects of high CO2, UVR and nutrients varied among different functional groups. Increased UVR had negative effects on diatoms and cyanobacteria and positive effects on cryptophytes, whereas increased CO2 inhibited cyanobacteria but increased cryptophyte growth. A positive synergistic interaction between CO2 and UVR was observed for diatoms; high CO2 counteracted the negative effects of UVR under ambient nutrient concentrations. Nutrient enrichments suppressed the negative effects of high CO2 and UVR on cyanobacteria and diatoms, respectively. Beneficial effects of CO2 were observed for diatoms and cryptophytes under combined additions of nitrate and ammonium, suggesting that growth may be limited by DIC availability when the primary limitation by nitrogen is alleviated. Beneficial effects of high CO2 and UVR in diatoms were also induced or intensified by ammonium additions.

Cold-water corals are amongst the most three-dimensionally complex deep-sea habitats known and are associated with high local biodiversity. Despite their importance as ecosystem engineers, little is known about how these organisms will respond to projected ocean acidification. Since preindustrial times, average ocean pH has already decreased from 8.2 to ~ 8.1. Predicted CO2 emissions will decrease this by up to another 0.3 pH units by the end of the century. This decrease in pH may have a wide range of impacts upon marine life, and in particular upon calcifiers such as cold-water corals. Lophelia pertusa is the most widespread cold-water coral (CWC) species, frequently found in the North Atlantic. Data here relate to a short term data set (21 days) on metabolism and net calcification rates of freshly collected L. pertusa from Mingulay Reef Complex, Scotland. These data from freshly collected L. pertusa from the Mingulay Reef Complex will help define the impact of ocean acidification upon the growth, physiology and structural integrity of this key reef framework forming species.

Global climate change has intensified the need to assess the capacity for natural populations to adapt to abrupt shifts in the environment. Reductions in seawater pH constitute a conspicuous global change stressor that is affecting marine ecosystems globally. Here, we quantify the phenotypic and genetic modifications associated with rapid adaptation to reduced seawater pH in the Mediterranean mussel, Mytilus galloprovincialis. We reared a genetically diverse larval population in two pH treatments (pHT 8.1 and 7.4) and tracked changes in the shell-size distribution and genetic variation through settlement. Additionally, we identified differences in the signatures of selection on shell growth in each pH environment. Both phenotypic and genetic data show that standing variation can facilitate adaptation to declines in seawater pH. This work provides insight into the processes underpinning rapid evolution, and demonstrates the importance of maintaining variation within natural populations to bolster species' adaptive capacity as global change progresses.

Users are recommended to consult the author (malcolm.mistry@unive.it / malmistry1977@gmail.com) for an updated version which includes more recent years. Monthly and Annual Cooling/Heating degree-days (CDD/HDD) using daily average temperature (°C), and Cooling degree-days using daily average wet-bulb temperature (Twb), based on the following threshold (base) temperatures: CDD, CDDwb: 18, 18.3, 22, 23, 24 and 25 (°C) HDD: 10, 15, 15.5, 16, 17 and 18 (°C) The degree-days are computed using meteorological parameters from the Global Land Data Acquisation System (GLDAS) ver. 2 (@ 0.25 degree global gridded resolution). The dataset referred to as "DegDays_0p25_1970_2018" covers 49 years over the period 1970-2018. Units: Degree-Celsius Days. In order to convert to Degree-Fahrenheit Days, multiply by 1.8. e.g. CDD (°F) = 9/5* CDD (°C) Data files are compressed in tar.bz2 folder containing the individual NetCDF-4 (.nc4) and GeoTIFF (.tif). The files follow the naming convention 'gldas_0p25_deg_DD_base_T_degC_1970_2018_timescale.nc4'; wherein “DD” is the abbreviation of the index (CDD, CDDwb or HDD), degC is the threshold temperature used in the computation of Tb, and “timescale” either “ann” or “mon” relating to annual or monthly timescales over which the corresponding degree-days are computed. Grid-cells with missing values are identified by “1.e+20f”. Important: GLDAS ver-2 comprises of two sub-versions (ver. 2.0 for period 1970-2010 and ver 2.1 for period 2000-present day). The degree-days computed using the input temperature and variables may show a break in time-series at a few locations around the years 2010-11. Users are therefore advised caution when using the data for trend analysis for instance. Further details on the merging of the two versions can be found below: https://disc.gsfc.nasa.gov/information/faqs?title=Should%20I%20use%20GLDAS%20Version%202.0%20(GLDAS-2.0)%20or%20GLDAS%20Version%202.1%20(GLDAS-2.1)%3F

Vazella pourtalesi presence and absence data were obtained from several different sources: DFO's multispecies trawl survey conducted in the Maritimes Region between 2007 to 2017 (presences and absences), DFO optical (in-house camera/video and remotely operated vehicle) benthic surveys conducted between 2001 and 2017 (presences only), and commercial bycatch records from the Fisheries Observer Program (FOP) from 1997 to 2007, and 2010 to 2015 (presences only). The DFO multispecies trawl survey is stratified random (by depth) and conducted using primarily Western IIA trawl gear. The average distance of these tows is ~ 3.17 km. Absence records were created from null (zero) catches that occurred in the same surveys. Commercial bycatch data between 1997 to 2007 from the Fisheries Observer Program was further post-processed and validated for accuracy, while the data from 2010 to 2015 was extracted directly from the Maritimes Fishery Science Database managed by DFO. Commercial trawls are much longer in duration and may follow bottom contours and/or retrace their footprint through the course of a 10+ km tow. For both the DFO multispecies trawl survey and FOP data, start coordinates were used to represent the tow, whereas for the DFO benthic imagery survey data the actual location of the V. pourtalesi record in situ was used. A 1 x 1 km grid matching that of the environmental data was placed over the study area and the presence-absence data were reduced to one record per cell, with a presence taking precedence over an absence if both occurred in the same cell. This gave a total of 215 presences (102 from the DFO trawl surveys, 47 from DFO benthic science surveys, and 66 from the FOP) and 2867 absences for the model.

Two mesocosm experiments, PAME-I and PAME-II were conducted in 2007 and 2008 to investigate fate of organic carbon in the arctic microbial food web. Mesocosms were nutrient fertilized initially to induce phytoplankton bloom development. In PAME-I eight units (each 700 L) formed two four point gradients of additional DOC in form of glucose (0, 0.5, 1 and 3 times Redfield ratio in terms of carbon relative to the nitrogen and phosphorus additions) (Fig. 1). All the eight units also got a daily dose of NH4+ and PO4**3- in Redfield ratio. Two gradients were set up, one with silicate addition, performed in the Arctic location Ny Ålesund, Svalbard, have previously been reported to give different food-web level responses to similar nutrient perturbations. In PAME-II all ten units (each 900 L) formed two four point gradients of additional DOC in form of glucose (0, 0.5, 1, 2 and 3 times Redfield ratio in terms of carbon relative to nitrogen and phosphorus additions). The two gradients in glucose were kept silicate replete. NH4+ was used as the DIN source in one gradient (units 1 to 5) and NO3- in the other (units 6-9). All units got a daily dose of PO4**3- in Redfield ratio. Prokaryotes and viruses were measured by flow cytometry, while ciliate abundances were counted using a Flow Cam. Viral and bacterial diversity was measured by PFGE and DGGE, respectively. In PAME-II the abundance of ciliates was lower than in PAME-I, presumably caused by higher copepod grazing. The abundances of prokaryotes and viruses were also lower in PAME-II compared to PAME-I. Further, less diversity was detected in the viral community (FCM and PFGE) in PAME-II, and no response was observed in the bacterial community structure due to addition of organic carbon.

Laboratory experiments were performed measuring calcification rates in Baltic Sea mussel at various salintiies, bicarbonate and calcium ion concentrations. Predictors of calcification were calculated and correlated with calcification rates. Field monitoring of carbonate chemistry, salinity and temperature was conducted and correlated with field calcification rates in southwest Baltic Sea mussel reefs.