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This paper aims to describe the spatial-temporal variability in catch of the main fishery resources of the Amazon River and floodplain lakes of the Lower Amazon, as well as relating the Catch per Unit of Effort with anomalies of some of the Amazon River, atmosphere and Atlantic Ocean system variables, determining the influence of the environment on the Amazonian fishery resources. Finfish landings data from the towns and villages of the Lower Amazon for the fisheries of three sites (Óbidos, Santarém and Monte Alegre), were obtained for the period between January 1993 and December 2004. Analysis of variance, detrended correspondence analysis, redundancy analysis and multiple regression techniques were used for the statistical analysis of the distinct time series. Fisheries production in the Lower Amazon presents differences between the Amazon River and the floodplain lakes. Production in the Amazon River is approximately half of the one of the floodplain lakes. This variability occurs both along the Lower Amazon River region (longitudinal gradient) and laterally (latitudinal gradient) for every fishing ground studied here. The distinct environmental variables alone or in association act differently on the fishery stocks and the success of catches in each fishery group studied here. Important variables are the flooding events; the soil the sea surface temperatures; the humidity; the wind and the occurence of El Niño-Southern Oscillation events. Fishery productivity presents a large difference in quantity and distribution patterns between the river and floodplain lakes. This variability occurs in the region of the Lower Amazon as well as laterally for each fishery group studied, being dependent on the ecological characteristics and life strategies of each fish group considered here.

AbstractThe mean predicted decrease of 0.3–0.4 pHunits in the global surface ocean by the end of the century has prompted urgent research to assess the potential effects of ocean acidification on the marine environment, with strong emphasis on calcifying organisms. Among them, the Mediterranean red coral (Corallium rubrum) is expected to be particularly susceptible to acidification effects, due to the elevated solubility of its Mg‐calcite skeleton. This, together with the large overexploitation of this species, depicts a bleak future for this organism over the next decades. In this study, we evaluated the effects of lowpHon the species from aquaria experiments. Several colonies ofC. rubrumwere long‐term maintained for 314 days in aquaria at two differentpHlevels (8.10 and 7.81,pHT). Calcification rate, spicule morphology, major biochemical constituents (protein, carbohydrates and lipids) and fatty acids composition were measured periodically. Exposure to lowerpHconditions caused a significant decrease in the skeletal growth rate in comparison with the control treatment. Similarly, the spicule morphology clearly differed between both treatments at the end of the experiment, with aberrant shapes being observed only under the acidified conditions. On the other hand, while total organic matter was significantly higher under lowpHconditions, no significant differences were detected between treatments regarding total carbohydrate, lipid, protein and fatty acid composition. However, the lower variability found among samples maintained in acidified conditions relative to controls, suggests a possible effect ofpHdecrease on the metabolism of the colonies. Our results show, for the first time, evidence of detrimental ocean acidification effects on this valuable and endangered coral species.

In the present study we used the high-throughput sequencing technology Illumina MiSeq to develop 26 polymorphic microsatellite loci for the marine snailGibbula divaricata. Four to 32 alleles were detected per locus across 30 samples analyzed. Observed and expected heterozygosities ranged from 0.130 to 0.933 and from 0.294 to 0.956, respectively. No significant linkage disequilibrium existed. Seven loci deviated from Hardy-Weinberg equilibrium that could not totally be explained by the presence of null alleles. Sympatric distribution with other species of the genusGibbula, asG. rarilineataandG. varia, lead us to test the cross utility of the developed markers in these two species, which could be useful to test common biogeographic patterns or potential hybridization phenomena, since morphological intermediate specimens were found.

The Instituto Español de Oceanografía (IEO, Spanish Institute of Oceanography) has maintained different monitoring programs in the Spanish Mediterranean waters (Western Mediterranean) since 1992. All these monitoring programs were unified in 2007 under the current program RADMED (series temporales de datos oceanográficos en el Mediterráneo), which is devoted to the in situ multidisciplinary sampling of the water column of coastal and open-sea waters by means of periodic oceanographic campaigns. These campaigns, together with a network of tide-gauges, are part of the IEO Observing system (IEOOS). In some cases, the temperature and salinity time series collected in the frame of these monitoring programs are now more than 30 years long, whereas sea level time series date to the beginning of the 1940s. This information has been complemented with international databases and has been analyzed in numerous works by the Grupo mediterráneo de Cambio Climático (GCC; Mediterranean Climate Change Group) for more than 20 years. These works have been devoted to the detection and quantification of the changes that climate change is producing on the physical, chemical, and biological properties of the Spanish Mediterranean waters. In this work, we review the results obtained by the GCC since 2005 in relation to the changes in the physical properties of the sea: water column temperature, salinity, and density, heat content, mixed layer depth, and sea level. Time series and results are updated from the last works, and the reliability of the existing time series for the detection of climatologies and long-term trends are analyzed. Furthermore, the different sources of uncertainty in the estimation of linear trends are considered in the present work. Besides this review and update of the results obtained from the data collected in the frame of the IEOOS, we conduct a review of the existing monitoring capabilities from other institutions in the Spanish Mediterranean waters and a review of results dealing with climate change in the Spanish Mediterranean obtained by such institutions. In particular, we include a review of the results obtained by SOCIB (Servicio de Observación y Predicción Costero de las Islas Baleares; Balearic Islands costal observing and forecasting system) in relation to the study of marine heat waves and the warming of the sea surface, and the results corresponding to the intense warming of the Catalan continental shelf at L’Estartit oceanographic station. All these results evidence that the surface Spanish Mediterranean waters are warming up at a rate higher than that affecting the global ocean (>2 °C/100 years). This warming and a salinity increase are also observed along the whole water column. Marine heat waves are increasing their intensity, frequency, and duration since 1982, and coastal sea level is increasing at a rate of 2.5 mm/yr. The salinity increase seems to have compensated for the warming, at least at surface and intermediate waters where no significant trends have been detected for the density. This could also be the reason for the lack of significant trends in the evolution of the mixed layer depth. All these results highlight the importance of monitoring the water column and the necessity of maintaining in situ sampling programs, which are essential for the study of changes that are occurring throughout the Spanish Mediterranean waters.

Abstract. Phytoplankton identification and abundance data are now commonly feeding plankton distribution databases worldwide. This study is a first attempt to compile the largest possible body of data available from different databases as well as from individual published or unpublished datasets regarding diatom distribution in the world ocean. The data obtained originate from time series studies as well as spatial studies. This effort is supported by the Marine Ecosystem Model Inter-Comparison Project (MAREMIP), which aims at building consistent datasets for the main Plankton Functional Types (PFT) in order to help validate biogeochemical ocean models by using carbon (C) biomass derived from abundance data. In this study we collected over 293 000 individual geo-referenced data points with diatom abundances from bottle and net sampling. Sampling site distribution was not homogeneous, with 58% of data in the Atlantic, 20% in the Arctic, 12% in the Pacific, 8% in the Indian and 1% in the Southern Ocean. A total of 136 different genera and 607 different species were identified after spell checking and name correction. Only a small fraction of these data were also documented for biovolumes and an even smaller fraction was converted to C biomass. As it is virtually impossible to reconstruct everyone's method for biovolume calculation, which is usually not indicated in the datasets, we decided to undertake the effort to document, for every distinct species, the minimum and maximum cell dimensions, and to convert all the available abundance data into biovolumes and C biomass using a single standardized method. Statistical correction of the database was also adopted to exclude potential outliers and suspicious data points. The final database contains 90 648 data points with converted C biomass. Diatom C biomass calculated from cell sizes spans over eight orders of magnitude. The mean diatom biomass for individual locations, dates and depths is 141.19 μg C l−1, while the median value is 11.16 μg C l−1. Regarding biomass distribution, 19% of data are in the range 0–1 μg C l−1, 29% in the range 1–10 μg C l−1, 31% in the range 10–100 μg C l−1, 18% in the range 100–1000 μg C l−1, and only 3% >1000 μg C l−1. Interestingly, less than 50 species contributed to >90% of global biomass, among which centric species were dominant. Thus, placing significant efforts on cell size measurements, process studies and C quota calculations on these species should considerably improve biomass estimates in the upcoming years. A first-order estimate of the diatom biomass for the global ocean ranges from 449 to 558 Tg C, which converts to 5 to 6 Tmol Si and to an average Si biomass turnover rate of 0.11 to 0.20 d−1. Link to the dataset: preliminary link http://doi.pangaea.de/10.1594/PANGAEA.777384.