Interrelationships Between Vent Fluid Chemistry, Temperature, Seismic Activity, and Biological Community Structure at a Mussel-Dominated, Deep-Sea Hydrothermal Vent Along the East Pacific Rise

In April 1991, submarine volcanic eruptions initiated the formation of numerous hydrothermal vents between 9°45′ and 9°52′N along the crest of the East Pacific Rise (EPR). Dramatic changes in biological community structure and vent fluid chemistry have been documented throughout this region since the eruptive event. By April 2004, mussels (Bathymodiolus thermophilus) dominated the faunal assemblages at several of the vent sites formed during of after the 1991 eruptions, whereas other habitats within the region were dominated by the vestimentiferan Riftia pachyptila. In the present paper, we build upon the extensive data sets obtained at these sites over the past decade and describe a manipulative experiment (conducted at 9°49.94′N; 104°14.43′W on the EPR) designed to assess interrelationships between vent fluid chemistry, temperature, biological community structure, and seismic activity. To this end, in situ voltammetric systems and thermal probes were used to measure H₂S/HS− and temperature over time in a denuded region of an extensive mussel bed in which an exclusion cage was placed to inhibit the subsequent migration of mussels into the denuded area. Fluid samples were taken from the same locations to characterize the associated microbial constituents. Basalt blocks, which were placed in the cage in April 2004 and subsequently recovered in April 2005, were colonized by more than 25 different species of invertebrates, including numerous vestimentiferans and remarkably few mussels. Recorded temporal changes in vent fluid chemistry and temperature regimes, when coupled with microbiological characterization of the vent fluids and seismic activity data obtained from ocean bottom seismometers, shed considerable light on factors controlling biological community structure in these hydrothermal ecosystems

The Primarily Undergraduate Nanomaterials Cooperative: A New Model for Supporting Collaborative Research at Small Institutions on a National Scale

The Primarily Undergraduate Nanomaterials Cooperative (PUNC) is an organization for research-active faculty studying nanomaterials at Primarily Undergraduate Institutions (PUIs), where undergraduate teaching and research go hand-in-hand. In this perspective, we outline the differences in maintaining an active research group at a PUI compared to an R1 institution. We also discuss the work of PUNC, which focuses on community building, instrument sharing, and facilitating new collaborations. Currently consisting of 37 members from across the United States, PUNC has created an online community consisting of its Web site (nanocooperative.org), a weekly online summer group meeting program for faculty and students, and a Discord server for informal conversations. Additionally, in-person symposia at ACS conferences and PUNC-specific conferences are planned for the future. It is our hope that in the years to come PUNC will be seen as a model organization for community building and research support at primarily undergraduate institutions

Formation of Zn- and Fe-sulfides near hydrothermal vents at the Eastern Lau Spreading Center: implications for sulfide bioavailability to chemoautotrophs

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

Estimation of local and external contributions of biomass burning to PM2.5 in an industrial zone included in a large urban settlement

A total of 85 PM2.5 samples were collected at a site located in a large industrial zone (Porto Marghera, Venice, Italy) during a 1-year-long sampling campaign. Samples were analyzed to determine water-soluble inorganic ions, elemental and organic carbon, and levoglucosan, and results were processed to investigate the seasonal patterns, the relationship between the analyzed species, and the most probable sources by using a set of tools, including (i) conditional probability function (CPF), (ii) conditional bivariate probability function (CBPF), (iii) concentration weighted trajectory (CWT), and (iv) potential source contribution function (PSCF) analyses. Furthermore, the importance of biomass combustions to PM2.5 was also estimated. Average PM2.5 concentrations ranged between 54 and 16 μg m−3 in the cold and warm period, respectively. The mean value of total ions was 11 μg m−3 (range 1–46 μg m−3): The most abundant ion was nitrate with a share of 44 % followed by sulfate (29 %), ammonium (14 %), potassium (4 %), and chloride (4 %). Levoglucosan accounted for 1.2 % of the PM2.5 mass, and its concentration ranged from few ng m−3 in warm periods to 2.66 μg m−3 during winter. Average concentrations of levoglucosan during the cold period were higher than those found in other European urban sites. This result may indicate a great influence of biomass combustions on particulate matter pollution. Elemental and organic carbon (EC, OC) showed similar behavior, with the highest contributions during cold periods and lower during summer. The ratios between biomass burning indicators (K+, Cl−, NO3−, SO42−, levoglucosan, EC, and OC) were used as proxy for the biomass burning estimation, and the contribution to the OC and PM2.5 was also calculated by using the levoglucosan (LG)/OC and LG/PM2.5 ratios and was estimated to be 29 and 18 %, respectively