Evaluating Terrestrial Carbon Sequestration Options for Virginia

Changes in forest and agricultural land management practices have the potential to increase carbon (C) storage by terrestrial systems, thus offsetting C emissions to the atmosphere from energy production. This study assesses that potential for three terrestrial management practices within the state of Virginia, USA: afforestation of marginal agricultural lands; afforestation of riparian agricultural lands; and changing tillage practices for row crops; each was evaluated on a statewide basis and for seven regions within the state. Lands eligible for each practice were identified, and the C storage potential of each practice on those lands was estimated through a modeling procedure that utilized land-resource characteristics represented in Geographic Information System databases. Marginal agricultural lands’ afforestation was found to have the greatest potential (1.4 Tg C yr⁻¹, on average, over the first 20 years) if applied on all eligible lands, followed by riparian afforestation (0.2 Tg C yr⁻¹ over 20 years) and tillage conversion (0.1 Tg C yr⁻¹ over 14 years). The regions with the largest potentials are the Ridge and Valley of western Virginia (due to extensive areas of steep, shallow soils) and in the Mid-Atlantic Coastal Plain in eastern Virginia (wet soils). Although widespread and rapid implementation of the three modeled practices could be expected to offset only about 3.4% of Virginia’s energy-related CO₂ emissions over the following 20 years (equivalent to about 8.5% of a Kyoto Treaty–based target), they could contribute to achievement of C-management goals if implemented along with other mitigation measures.     

Cobalt speciation assay for human serum,Part II. Method validation in a study of human volunteers ingesting cobalt(II) chloride dietary supplement for 90 days

A new analytical method for determining cobalt (Co) species in human serum by size exclusion chromatography with inductively coupled plasma mass spectrometry (SEC-ICP-MS) was applied to serum samples collected from 12 human volunteers who participated in a Co(II) chloride supplement study involving ingestion of 1 mg Co/day for up to 90 consecutive days. The study protocol included determination of serum total Co by acid digestion followed by ICP-MS. Co speciation assay measurements were conducted for up to 13 time points per individual spanning from one to two weeks before dosing began to two weeks after dosing ceased. The Co speciation assay showed good recovery >91% relative to total Co measurements. Undiluted serum demonstrated uniform fractions of large molecular Co defined as Co bound to albumin and other proteins >50 kDa at 96% and the residual as small molecular Co defined as free Co(II) and <1 kDa Co-complexes for individual serum Co concentrations up to 146 μg/L. There were no dose-related changes in Co distribution. Analysis of the same serum samples with tenfold dilution in 0.1 M acetic acid led to a lower fraction of large molecular Co at 87%, with the difference between diluted and undiluted measurements being 8.4%. The difference noted between undiluted and diluted large molecular Co may be attributed to Co release from albumin. Data demonstrated that large molecular Co was the predominant Co species in both undiluted and diluted human serum over a broad range of in vivo Co concentrations, reflecting high albumin–Co binding capacity. These data validate the Co speciation assay and may be employed in understanding further the toxicokinetics and dose-response relationships for Co species.     

Mitomycin C induced chromosome damage in fetal blood cultures and prenatal diagnosis of fanconi's anaemia

We report the use of fetal blood for the prenatal diagnosis of Fanconi anaemia (FA). The clastogenic action of Mitomycin C (MMC) is compared in blood cultures from different fetuses, normal controls and FA heterozygotes. The fetus at risk is shown to suffer from FA on the grounds of excessive chromosome breakage, both spontaneous and MMC induced.     

A survey of DNA methylation across social insect species, life stages, and castes reveals abundant and caste-associated methylation in a primitively social wasp

DNA methylation plays an important role in the epigenetic control of developmental and behavioral plasticity, with connections to the generation of striking phenotypic differences between castes (larger, reproductive queens and smaller, non-reproductive workers) in honeybees and ants. Here, we provide the first comparative investigation of caste- and life stage-associated DNA methylation in several species of bees and vespid wasps displaying different levels of social organization. Our results reveal moderate levels of DNA methylation in most bees and wasps, with no clear relationship to the level of sociality. Strikingly, primitively social Polistes dominula paper wasps show unusually high overall DNA methylation and caste-related differences in site-specific methylation. These results suggest DNA methylation may play a role in the regulation of behavioral and physiological differences in primitively social species with more flexible caste differences.     

A Tale of Two Rivers: Implications of Water Management Practices for Mussel Biodiversity Outcomes During Droughts

Droughts often pose situations where stream water levels are lowest while human demand for water is highest. Here we present results of an observational study documenting changes in freshwater mussel communities in two southern US rivers during a multi-year drought. During a 13-year period water releases into the Kiamichi River from an impoundment were halted during droughts, while minimum releases from an impoundment were maintained in the Little River. The Kiamichi observed nearly twice as many low-flow events known to cause mussel mortality than the Little, and regression tree analyses suggest that this difference was influenced by reduced releases. During this period mussel communities in the Kiamichi declined in species richness and abundance, changes that were not observed in the Little. These results suggest that reduced releases during droughts likely led to mussel declines in one river, while maintaining reservoir releases may have sustained mussel populations in another.     

Participatory and multi-level governance: applications to Aboriginal renewable energy projects

As provinces across Canada seek to diversify their domestic electricity supply and cope with the accelerating effects of anthropogenic climate change, new models of sustainability-focused economic development are being pursued. One critically important emerging paradigm involves First Nation (a Canadian term for indigenous) collaboration and leadership in renewable energy projects. In this comparative case study analysis, we consider two different governance approaches pursued in distinct renewable energy project contexts: the clean energy projects of the Ojibway Pic River First Nation band in northwestern Ontario and the NaiKun Offshore Wind Project proposed in the ocean territory of the Haida Nation off the coast of British Columbia (BC). Focusing on themes of participation and multi-level governance, the case studies highlight the importance of authority and control in decision processes, the primacy of ensuring that scale and quality of design are carefully scoped, and the shaping role of inclusiveness in planning for wholly sustainable energy futures. Taken together, these cases illustrate that fluid governance arrangements which exploit the particular capacities of each actor may give rise to trust that ultimately forms the foundation of a co-produced model of renewable energy governance. We argue that while collaboration might aim to be inclusive of all interested actors, it is important to consider the extent to which a project design might sufficiently incorporate a community's long-term vision. We conclude that truly sustainable renewable energy development requires a project design that reflects community values, incorporates community control, and incentivises indigenous ownership.