Indirect Benefits of Marine Protected Areas for Juvenile Abalone

Abstract: Marine protected areas ( MPAs) designed to provide harvest refugia for red sea urchins (  Strongylocentrotus franciscanus ) offer a unique opportunity to study the indirect effects of urchin fishing on subtidal communities. Sea urchins may provide important cryptic microhabitat for juvenile abalone sheltering beneath urchin spines in shallow habitats worldwide. We investigated the abundance of juvenile (3–90 mm) red abalone, (    Haliotis rufescens ) and the rare flat ( <90 mm) abalone (   H. walallensis ) on protected and fished rocky reefs in California. Abalone abundance surveys were conducted inside 24 × 30 m plots on three protected reefs with red sea urchins present and three fished reefs where red sea urchins were removed by commercial or experimental fishing. Significantly more juvenile abalone were found in 1996 and 1997 on protected reefs with urchins present than on fished reefs ( χ   ² = 188, df = 1, p < 0.001 ). Juvenile red abalone abundance was not correlated with local adult red abalone abundance or habitat rugosity. One-third of the juveniles inside the MPAs were found under the urchins' spine canopy, as were a suite of unfished marine organisms. In the laboratory, juvenile abalone survived better (  χ   ² = 7.31, df = 1, p < 0.01) in crab predation experiments in which red sea urchins were available as shelter. Fishing red urchins reduced structural complexity, potentially decreasing microhabitat available for juvenile abalone. This example demonstrates how MPAs designed for one fished species may help other species, illustrating their usefulness for ecosystem-based fishery management and marine conservation.     

Phylogenetic diversity and functional characterization of the Manila clam microbiota: a culture-based approach

According to the hologenome theory, the microbiota contributes to the fitness of the holobiont having an important role in its adaptation, survival, development, health, and evolution. Environmental stress also affects the microbiota and its capability to assist the holobiont in coping with stress factors. Here, we analyzed the diversity of cultivable bacteria associated with Manila clam tissues (mantle, gills, hemolymph) in two non-contaminated sites (Portugal and France) and one metal-contaminated site (Portugal). A total of 240 isolates were obtained. Representative isolates (n = 198) of the overall diversity were identified by 16S rDNA sequencing and subjected to functional characterization. Isolates affiliated with Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes. Proteobacteria (mostly Pseudoalteromonadaceae and Vibrionaceae) were dominant in non-contaminated sites while Actinobacteria (mostly Microbacteriaceae) dominated in the metal-contaminated site. The main factor affecting the microbiota composition was contamination. No significant differences were observed between clam tissues and geographic regions. Several isolates tested positive for antibacterial activity, biofilm formation, protease, and siderophore production. The results show that the Manila clam harbors a diverse microbiota that may contribute to clam protection and overall fitness, as well as to its adaptation to stressful environments. In addition, the Manila clam microbiota is revealed as a promising source of novel probiotics with potential application in aquaculture.     

Nitrogen footprints: Regional realities and options to reduce nitrogen loss to the environment

Ambio - Nitrogen (N) management presents a sustainability dilemma: N is strongly linked to energy and food production, but excess reactive N causes environmental pollution. The N footprint is an...     

Science Communication and Stakeholder Expertise: Insights from Sustainability Science*

Communicating science is a multifaceted and complex process, particularly in sustainability science where researchers directly engage with non-academic stakeholder partners. In this insight, we explore the relationship between science communication behaviour and perceptions of stakeholder scientific expertise in a large-scale sustainability-focused research project in the Northeastern United States. We find that higher levels of perceived scientific expertise are associated with dialogic and participatory models of communication, and lower levels of perceived scientific expertise are associated with dialogic and diffusion models of communication. This work, while small in scope, highlights the utility of attending to perceptions of expertise within stakeholder engagement contexts. Implications, limitations, and opportunities for future research are discussed.     

Bacterial Cellulose from Simple and Low Cost Production Media by Gluconacetobacter xylinus

Bacterial cellulose pellicles were produced by Gluconacetobacter xylinus using non conventional low-cost carbon sources, such as glycerol remaining from biodiesel production and grape bagasse, a residue of wine production. The carbon sources assayed showed their suitability for microbial cellulose production, with relatively high production values such as 10.0 g/l for the culture medium with glycerol from biodiesel as carbon source and corn steep liquor as nitrogen source; and 8.0 g/l for the culture medium containing grape bagasse and corn steep liquor. Glucose, commercial glycerol and cane molasses were also assayed as carbon sources for comparison. The bacterial celluloses produced were characterized by means of scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy and thermogravimetric analysis. Morphological analysis showed that bacterial cellulose microfibrils produced from the non-conventional media used were several micrometers long and had rectangular cross-sections with widths and thicknesses in the range of 35–70 and 13–24 nm, respectively. X-ray patterns showed crystallinity levels in the range of 74–79 % (area method), whereas both X-ray patterns and infrared spectroscopy evidenced the presence of peaks characteristic of Cellulose I polymorph. Besides thermal properties were similar to those found for the pellicle obtained from glucose. The study performed showed the suitability of using wine residues or glycerol remaining from increasing biodiesel production as cheap carbon sources for production of bacterial cellulose microfibrils, with similar characteristics as those obtained by use of more expensive carbon sources such as glucose or commercial glycerol. On the other hand, the low cost nitrogen sources used (corn steep liquor or diammonium phosphate) also contributed to the economy of the bioprocess.     

Endocrine-disrupting chemicals in coastal lagoons of the Po River delta: sediment contamination,bioaccumulation and effects on Manila clams

The large estuary that the River Po forms at its confluence into the Adriatic Sea comprises a multitude of transitional environments, including coastal lagoons. This complex system receives the nutrients transported by the River Po but also its load of chemical contaminants, which may pose a substantial (eco)toxicological risk. Despite the high ecological and economic importance of these vulnerable environments, there is a substantial lack of information on this risk. In light of the recent amendments of the European Water Framework Directive (2013/39/EU), the present study investigated the sediment contamination of six coastal lagoons of the Po delta and its effects on Manila clams (Ruditapes philippinarum), exposed in situ for 3 months. Sediment contamination and clam bioaccumulation of a wide range of chemicals, i.e. trace metals (Cd, Cr, Ni, Hg, Pb, As), polybrominated diphenyl ethers (PBDEs), alkylphenols (APs), organochlorine compounds (PCBs, DDTs), polycyclic aromatic hydrocarbons (PAHs) and organotins (TPhT, TBT), suggested a southward increase related to the riverine transports. Where the River Po influence was more direct, the concentrations of contaminants were higher, with nonylphenol and BDE-209 exceeding sediment quality guidelines. Biometric indicators suggested the influence of contamination on organism health; an inverse relationship between PBDEs in sediments and clam condition index has been found, as well as different biota-sediment accumulation factors (BSAFs) in the lagoons.     

Monuments as sampling surfaces of recent traffic pollution

Background, aim and scope  

A new approach towards monuments, considering them as a passive sampler of pollution, is presented. Cultural Heritage objects suffer daily the damages of environmental pollution, especially in those areas interested by heavy traffic. Since monuments undergo only periodic conservation or maintenance works, surfaces are able to accumulate atmospheric deposit and to record changes in its composition. An optimised analytical protocol was developed in order to quantify platinum and rhodium at trace level on surfaces. The two elements have become tracers of automobile emissions in recent years, since the introduction of catalytic converters, and could have catalytic effects on the decay reactions of natural and artificial stone materials. As a first case study, the cement mortar surfaces of a twentieth century monument, the Camerlata Fountain, in Como (Italy) were investigated.