A virtual “field test” of forest management carbon offset protocols: the influence of accounting

Of the greenhouse gas (GHG) mitigation options available from U.S. forests and agricultural lands, forest management presents amongst the lowest cost and highest volume opportunities. A number of carbon (C) accounting schemes or protocols have recently emerged to track the mitigation achieved by individual forest management projects. Using 50-year C cycling data from the Calhoun Experimental Forest in South Carolina, USA, C storage is estimated for a hypothetical forest management C offset project operating under seven of these protocols. After 100 years of project implementation, net C sequestration among the seven protocols varies by nearly a full order of magnitude. This variation stems from differences in how individual C pools, baseline, leakage, certainty, and buffers are addressed under each protocol. This in turn translates to a wide variation in the C price required to match the net present value of the non-project, business-as-usual alternative. Collectively, these findings suggest that protocol-specific restrictions or requirements are likely to discount the amount of C that can be claimed in “real world” projects, potentially leading to higher project costs than estimated in previous aggregate national analyses.     

SARS-CoV2 (COVID-19) infection: is fetal surgery in times of national disasters reasonable?

Even though the global COVID-19 pandemic may affect how medical care is delivered in general, most countries try to maintain steady access for women to routine pregnancy care, including fetal anomaly screening. This means that, also during this pandemic, fetal anomalies will be detected, and that discussions regarding invasive genetic testing and possibly fetal therapy will need to take place. For patients, concerns about Severe Acute Respiratory Syndrome-Corona Virus 2 will add to the anxiety caused by the diagnosis of a serious fetal anomaly. Yet, also for fetal medicine teams the situation gets more complex as they must weigh up the risks and benefits to the fetus as well as the mother, while managing a changing evidence base and logistic challenges in their healthcare system.     

Active and legacy mining in an arid urban environment: challenges and perspectives for Copiapó, Northern Chile

Urban expansion in areas of active and legacy mining imposes a sustainability challenge, especially in arid environments where cities compete for resources with agriculture and industry. The city of Copiapó, with 150,000 inhabitants in the Atacama Desert, reflects this challenge. More than 30 abandoned tailings from legacy mining are scattered throughout its urban and peri-urban area, which include an active copper smelter. Despite the public concern generated by the mining-related pollution, no geochemical information is currently available for Copiapó, particularly for metal concentration in environmental solid phases. A geochemical screening of soils (n = 42), street dusts (n = 71) and tailings (n = 68) was conducted in November 2014 and April 2015. Organic matter, pH and elemental composition measurements were taken. Notably, copper in soils (60–2120 mg/kg) and street dusts (110–10,200 mg/kg) consistently exceeded international guidelines for residential and industrial use, while a lower proportion of samples exceeded international guidelines for arsenic, zinc and lead. Metal enrichment occurred in residential, industrial and agricultural areas near tailings and the copper smelter. This first screening of metal contamination sets the basis for future risk assessments toward defining knowledge-based policies and urban planning. Challenges include developing: (1) adequate intervention guideline values; (2) appropriate geochemical background levels for key metals; (3) urban planning that considers contaminated areas; (4) cost-effective control strategies for abandoned tailings in water-scarce areas; and (5) scenarios and technologies for tailings reprocessing. Assessing urban geochemical risks is a critical endeavor for areas where extreme events triggered by climate change are likely, as the mud flooding that impacted Copiapó in late March 2015.     

Harbours as marine habitats: hydroid assemblages on sea-walls compared with natural habitats

Sessile hydrozoans constitute a common component of marine rocky communities. We compared the hydrozoan assemblages occurring on sea-walls of commercial harbours with those on natural rocky cliffs along the southern Iberian Peninsula, to identify differences in the multivariate structure of the assemblages and species richness. Harbour hydroid assemblages significantly differed from natural ones mainly due to their qualitative composition. Medusa-less taxa, optimized for low dispersal and long-term persistence on the substratum, are barely represented in harbours, but abundant at natural sites. “Port species” assemblages were composed of (1) small, short-living species with typical opportunistic characteristics; (2) cosmopolitan large-size taxa, significantly represented both in harbours and in natural habitats; (3) non-indigenous species. Contrarily to the expected lower richness of communities in confined areas, our results demonstrate that richness of hydroid assemblages in harbours is comparable to that of natural habitats.     

Sperm polymorphism and genetic divergence in the mussel Perumytilus purpuratus

For the first time in a marine bivalve species, geographic intraspecific variation in sperm morphology in the Chilean mussel, Perumytilus purpuratus, is reported. Samples were obtained in December 2010 from the rocky intertidal at three locations: Antofagasta (23o44′01.08′′S, 70o26′26.11′′W), Valparaíso (32o57′23.07′′S, 71o33′01.86′′W), and Valdivia (39°50′44.26′′S, 73°25′51.99′′W). Scanning electron microscopy was used to describe sperm traits, and genetic data were obtained by sequencing a 16S mtDNA 427-bp fragment. The results showed geographic intraspecific variation with two statistically significant patterns of genetically differentiated sperm morphologies. One genetic clade was found for Antofagasta and Valparaíso, displaying a unique sperm morphotype with a short acrosome accounting for 26 % of the head length, and the other from Valdivia, with a larger acrosome occupying 47 % of the head length. These results will lead to new research to distinguish among alternative hypotheses: the presence of cryptic species, incipient speciation, or a polymorphism in sperm traits of P. purpuratus.     

Reproduction and imposex in the edible snail <Emphasis Type="Italic">Adelomelon ancilla</Emphasis> from northern Patagonia,Argentina

The edible volutid snail Adelomelon ancilla occurs on the Argentine coast and may have the capacity to serve as source of support for local fisheries. However, knowledge of its reproduction is lacking. Over 3 years (from September 2000 to July 2004) we studied the oviposition at Golfo Nuevo, Patagonia by diving. Monthly collections were performed to examine gonadal stages histologically during 2002–2003. Gamete development stages corresponded with the expected period for oviposition occurring from July to November, a time of increasing day length. Oviposition also took place in March when water temperature attained a maximum of 18°C. Following the spawning period, remaining gametes were resorpted in both sexes. Males contained sperm throughout the year, parasperm and eusperm forms were found within the same acinus. Oogonia/oocytes ranged from 20 to 240 μm in diameter during oogenesis. Females commenced laying egg capsules from a shell length of 114 mm. Reproduction is compared with other fishable volutid snails from the Argentine shelf, and suggests the need to apply certain fishing restrictions if the resource begins to be utilized commercially. The imposex condition was found in snails from some shipping areas. The frequency of this condition declined with distance from the port.     

Compositional analysis of topsoil metals and its associations with cancer mortality using spatial misaligned data

The presence of toxic metals in soil per se, and in soil impacted by mining, industry, agriculture and urbanisation in particular, is a major concern for both human health and ecotoxicology. The dual aim of this study was: to ascertain whether topsoil composition could influence the spatial distribution of mortality due to different types of cancer and to identify possible errors committed by epidemiological studies which analyse soil composition data as a closed number system. We conducted an ecological cancer mortality study, covering 861,440 cancer deaths (27 cancer sites) in 7917 Spanish mainland towns, from 1999 to 2008. Topsoil levels of Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn were determined by ICP-MS at 13,317 sampling points. We transformed the topsoil data in two ways, i.e. log transformation and centred logratio transformation. Principal factor analysis was performed to obtain independent latent factors for the transformed variables. To estimate the effect on mortality of topsoil factor loadings, we fitted Besag, York and Mollié models embedded in geostatistical-spatial models. This model included soil sample locations and town centroids (non-aligned data), fitted using the integrated nested Laplace approximation (INLA) as a tool for Bayesian inference and stochastic partial differential equations (SPDE). All results were adjusted for socio-demographic variables. The results indicated that soil composition could have an influence on the spatial distribution and mortality patterns of cancer. The analysis adjusted for socio-demographic variables showed excess male mortality due to digestive system tumours in areas with soils containing higher Cd, Pb, Zn, Mn and Cu concentrations, bladder cancer in areas with soils containing higher Cd concentrations, and brain cancer in areas with soils containing As. In both sexes, cancer of oesophagus was associated with soils containing a higher lead content, while lung cancer was associated with soils containing a higher copper content. Stress should be laid on the importance of taking into account the compositional nature of the data in this type of analysis.     

Neighborhood phylodiversity affects plant performance

Facilitation and competition are ecological interactions that are crucial for the organization of plant communities. Facilitative interactions tend to occur among distantly related species, while the strength of competition tends to decrease with phylogenetic distance. The balance between both types of interactions will ultimately determine the specific composition of multispecies associations. Although multispecies patches are the arena in which coexistence develops among different phylogenetic groups within communities, the specific processes that occur across life stages have not been explored. Here we study how different species, in composing discrete patches in central Mexico, exert competitive or facilitative effects on seeds and seedlings. We relate these interactions to phylogenetic relationships among nurse species and beneficiary species, and among members of the patches. Survivorship and growth rates of the columnar cactus Neobuxbaumia mezcalaensis were highly positively related to increasing phylogenetic distance to different nurse species, to the presence of related species in patches, and to mean phylogenetic distances to the rest of the species in the patch. Each of these three elements influenced N. mezcalaensis differently, with different nurse species varying substantially in their early effects on emergence, and the nearest relatives and species composition of patches varying in their late effects on survival and growth. Our results emphasize that evolutionary relationships among co-occurring species in vegetation clumps exert direct and indirect effects on plants, affecting individual performance and species coexistence.     

Submarine experiments on benthic colonization of sediments in the western Baltic Sea. I. Technical layout

Submarine sedimentary substrates have been exposed in a new-style special arrangement for benthic colonization. The experiment has been running for 2 years and is planned to continue as a long-term test for several more years, with the purpose of studying independently both the effects of hydrographic and biotic factors as well as those of substrate type. This is accomplished by 3 floating platforms. Each carries 3 open containers filled with clayey mud, sand, and gravel (70 cm diameter, 25 cm deep). The platforms are anchored close together at 11, 15 and 19 m water depths. Their distances from the sea floor vary between 5.5 and 2.0 m. The sediments were obtained from sand pits on land. Substrate samples are continuously taken by divers. Hydrographic data are available by direct measurements from a ship and automatic sensors. The characteristic sources of error of the experiment seem to exert no decisive influence on the benthic production data.