Evaluating an Air Quality Health Index (AQHI) amendment for communities impacted by residential woodsmoke in British Columbia,Canada

ABSTRACT

Smoke from burning biomass is an important source of fine particulate matter (PM_2.5), but the health risks may not be fully captured by the Canadian Air Quality Health Index (AQHI). In May 2018, the province of British Columbia launched an evidence-based amendment (AQHI-Plus) to improve AQHI performance for wildfire smoke, but the AQHI-Plus was not developed or tested on data from the residential woodsmoke season. This study assesses how the AQHI and AQHI-Plus are associated with acute health outcomes during the cooler seasons of 2010–2017 in British Columbia, Canada. Monthly and daily patterns of temperature and PM_2.5 concentrations were used to identify Local Health Areas (LHAs) that were impacted by residential woodsmoke. The effects of the AQHI and AQHI-Plus on five acute health outcomes (including non-accidental mortality, outpatient physician visits, and medical dispensations for cardiopulmonary conditions) were estimated using generalized linear mixed effect models with Poisson distributions adjusted for long- and short-term temperature trends. Values of the Akaike information criterion (AIC) were compared to evaluate whether the AQHI or AQHI-Plus was better fitted to each health outcome. Eleven LHAs were categorized as woodsmoke-impacted. In these LHAs, the AQHI and AQHI-Plus associations with acute health outcomes were sensitive to temperature adjustments. After temperature adjustments, the most consistent associations were observed for the two asthma-specific outcomes where the AQHI-Plus was better fitted than the AQHI. The improved performance of the AQHI-Plus for susceptible populations with asthma is consistent between communities impacted by residential woodsmoke and wildfire smoke.

Implications: Canada’s Air Quality Health Index (AQHI) is a three pollutant index used to communicate the short term health impact of degraded air quality. As fine particulate matter (PM_2.5) is the lowest weighted pollutant in the AQHI, the index is poorly reflective of woodsmoke impacts. The present analysis found that an AQHI amendment developed for improved sensitivity to PM_2.5 during wildfire seasons (AQHI-Plus) is also more predictive of acute asthma-related health outcomes in communities impacted by residential woodsmoke. The BC Ministry of Environment and Climate Change Strategy has piloted the AQHI-Plus year-round. Other jurisdictions should consider whether their air quality indices are reflective of the risks posed by woodsmoke.     

REASSEMBLING HETCH HETCHY: WATER SUPPLY WITHOUT O'SHAUGHNESSY DAM1

The Hetch Hetchy System provides San Francisco with most of its water supply. O'Shaughnessy Dam is one component of this system, providing approximately 25 percent of water storage for the Hetch Hetchy System and none of its conveyance. Removing O'Shaughnessy Dam has gained interest for restoring Hetch Hetchy Valley. The water supply feasibility of removing O'Shaughnessy Dam is analyzed by examining alternative water storage and delivery operations for San Francisco using an economic engineering optimization model. This model ignores institutional and political constraints and has perfect hydrologic foresight to explore water supply possibilities through reoperation of other existing reservoirs. The economic benefits of O'Shaughnessy Dam and its alternatives are measured in terms of the quantity of water supplied to San Francisco and agricultural water users, water treatment costs, and hydropower generation. Results suggest there could be little water scarcity if O'Shaughnessy Dam were to be removed, although removal would be costly due to additional water treatment costs and lost hydropower generation.     

Impacts of land use conversion on bankfull discharge and mass wasting

Mass wasting and channel incision are widespread in the Nemadji River watershed of eastern Minnesota and northwestern Wisconsin. While much of this is a natural response to glacial rebound, sediment coring and tree ring data suggest that land use has also influenced these erosional processes. We characterized land use, inventoried mass wasting, surveyed stream channels and collected discharge data along segments of five streams in the Nemadji River watershed. Due to natural relief in this region, wetlands and agricultural lands are concentrated in the flatter terrain of the uplands of the Nemadji watershed, while forestland (coniferous or deciduous) is concentrated in the deeply incised (50-200% slope) stream valleys. Bankfull discharge was higher where forests had been converted from coniferous to deciduous forests and where there were fewer wetlands. Mass wasting increased exponentially with bankfull flows. While mass wasting was not correlated with forest type conversion and agricultural land use, it was negatively dependent upon wetland extent in headwater areas. Interactions between the spatial distribution of land use and terrain obfuscate any clear cause-and-effect relationships between land use, hydrology and fluvial processes.     

Water scarcity: An alternative view and its implications for policy and capacity building

This article focuses on the somewhat ambiguous concept of scarce water, or, more accurately stated, on the rather more ambiguous concept of scarcity. Still today, water scarcity in a region is defined largely in physical terms, typically gallons or cubic metres per capita if a stock or per capita-year if a flow. However useful purely physical measures may be for broad comparisons, they cannot adequately reflect the variety of ways in which human beings use water — neither to their wastefulness when water is perceived as abundant nor to their ingenuity when it is not. This article argues that water scarcity should be defined according to three orders of scarcity that require, respectively, physical, economic and social adaptations. It goes on to demonstrate that perceiving scarcity mainly in physical terms limits opportunities for policy-making and approaches for capacity building.     

Human maternal uniparental disomy for chromosome 16 and fetal development

Two severely growth-retarded fetuses found to have maternal uniparental disomy (UPD) for chromosome 16 and trisomy 16 placental mosaicism both had an unfavourable outcome. Antenatally, the first case was complicated by an unexplained raised maternal serum alpha-fetoprotein concentration, preterm premature rupture of the membranes, and growth retardation detectable at 21 weeks' gestation, whilst the other had an unexplained raised maternal serum human chorionic gonadotrophin level, a two-vessel cord on ultrasound, and cessation of growth at 25 weeks. At post-mortem, both babies had an imperforate anus. Fetal maternal UPD may explain the poor outcome that occurs in some cases of confined placental mosaicism for chromosome 16 and is also associated with specific fetal abnormalities.     

Seamount endemism questioned by the geographic distribution and population genetic structure of marine invertebrates

Previous studies have suggested that the high diversity associated with the Norfolk seamounts (Southwest Pacific) could reflect endemism resulting from limited dispersal due to hydrological phenomena. Crustaceans of the family Galatheidae are thoroughly studied in the New Caledonia economic zone permitting the analysis of species distribution pattern between the New Caledonia slope and Norfolk ridge seamounts. This analysis has shown that, qualitatively, the same species are sampled on seamounts and on the New Caledonia slope. Local endemism was never detected. However, on each seamount, and therefore on a small surface, a very high number of species are usually sampled, suggesting that seamounts are biodiversity hot spots. Then, to evaluate whether the seamounts constitute patches of isolated habitat, we explore the pattern of genetic diversity within several species of crustaceans and gastropods. Analysis of the intra-specific genetic structure using the mitochondrial marker COI reveals that populations of two Galatheidae species (Munida thoe and Munida zebra), polymorphic for this marker, are genetically not structured, both among seamounts and between the seamounts and the island slope. The genetic structure over a similar sampling scheme of two Eumunida species (Chirostylidae, the sister family of Galatheidae) and a planktotrophic gastropod (Sassia remensa) reveals a similar pattern. Population structure is observed only in Nassaria problematica, a non-planktotrophic gastropod with limited larvae dispersal. Thus, the limitation of gene flow between seamounts appears to be observed only for species with limited dispersal abilities. Our results suggest that the Norfolk seamounts rather than functioning as areas of endemism, instead, may be highly productive zones that can support numerous species in small areas.     

Bio-Energy Systems at the Community Level in the South Pacific: Impacts & Monitoring

Read, Sims and Adams (2001) detailed a case study for bio-energy implementation in a notional small Pacific Island and elaborated a theoretical model for assessing and simulating the socio-economic impacts of a particular bio-energy system designed to produce an exportable liquid fuel along with rural electricity supplies. An important conclusion was that there is no silver-bullet ‘one size fits all’ bio-energy system suited to all situations. Moreover, a system appropriate at one place and time may become obsolete with exogenous technological advance and/or as a community advances down its own development pathway. In order to understand how these issues interact in practice, a selected set of implementation projects is reviewed highlighting scale, capacity, community, technology, governmental policy and the concept of critical mass, as factors that are central to the successful development of the bioenergy sector. Through this evaluation, it is shown that: 1.A significant biomass supply resource base often exists locally in the form of agricultural and forestry residues on which modern bioenergy programmes could be initiated. The use of biomass energy flow charts are an important tool for evaluating the potential of local and national resources. 2. Without an integrated multi-disciplinary, multi-sector and whole-systems approach to the implementation of bioenergy schemes, long term success is likely to remain elusive. 3. There is a requirement at the national level for a coordinated approach with strong policy signals that overcome perverse and practical obstacles.     

Influence of development and rearing temperature on the distribution,ultrastructure and myosin sub-unit composition of myotomal muscle-fibre types in the plaice Pleuronectes platessa

Eggs of the plaice Pleuronectes platessa L. were incubated at temperatures of 5, 8, 10, 12 and 15°C in March 1990, 1991 and 1992. The myotomes of yolk-sac larvae contain a single superficial layer of small-diameter muscle fibres which stain intensely for succinic dehydrogenase activity, surrounding 390 to 500 weakly staining inner-muscle fibres of larger diameter. Larvae reared at 15°C only survived for a few days and had significantly more inner-muscle fibres of larger average cross-sectional area than those hatching at 5 to 10°C. Myofibrils occupied 61% of the volume of inner-muscle fibres in 15°C larvae compared with 35 and 36% in larvae hatching at 5 and 10°C, respectively (P(0.01). Following metamorphosis, which occurs between 7 and 10 wk, the myotomes retain the single layer of superficial-muscle fibres characteristic of larvae. A thickening of the superficial-muscle layer is first evident in 4 to 5 mo-old laboratory-reared fish of 20 mm total length (TL) and in 0-group fish caught in June and July. On the basis of the histochemical staining reactions for myofibrillar ATPase and succinic dehydrogenase activities, the myotomes of 1-group (104 mm TL) and adult (280 mm TL) plaice were found to contain a minimum of six distinct muscle-fibre types. Two-dimensional gel electrophoresis and peptide mapping were used to investigate changes in myosin subunit composition during development. Myosin from the inner muscle of larvae contains two isoforms of the phosphorylatable light-chain 2 (LC2_L1 and LC2_L2). Following metamorphosis and during the first year, inner-muscle fibres co-express LC2 isoforms characteristic of the superficial fast-muscle fibres of adult plaice (LC2_F1 and LC2_F2) in addition to the larval isoforms. Fast-muscle fibres isolated from deep layers of the myotomes in adult plaice only contain LC2_F2. In contrast, myosin from larval muscle and adult fast muscle contain apparently identical alkali light chains (LC1 and LC3). Peptide maps of myosin heavy chains (MHCs) from 6 wk-old larvae and 10 wk-old fish that had completed metamorphosis are similar, but distinct from those of 1-group plaice. Further changes in white-muscle MHC composition are evident between 1-group fish of 104 mm TL and adults of 280 mm TL.     

Deforestation Predicts the Number of Threatened Birds in Insular Southeast Asia

The world's tropical forests are being cleared rapidly, and ecologists claim this is causing a massive loss of species. This claim has its critics. Can we predict extinctions from the extent of deforestation? We mapped the percentage of deforestation on the islands of the Philippines and Indonesia and counted the number of bird species found only on these islands. We then used the species-area relationship to calculate the number of species predicted to become globally extinct following deforestation on these islands. Next, we counted the numbers of insular southeast Asian endemic bird species considered threatened—i.e., those having "a high probability of extinction in the wild in the medium-term future"—in the latest summary Red Data Book. The numbers of extinctions predicted from deforestation and the numbers of species actually threatened are strikingly similar. This suggests we can estimate the size of the extinction crisis in once-forested regions from the extent of deforestation. The numbers of extinctions will be large. Without rapid and effective conservation, many of the species endemic to insular southeast Asia will soon be lost.     

Stream ecosystem response to limestone treatment in acid impacted watersheds of the Allegheny Plateau.

Restoration programs are expanding worldwide, but assessments of restoration effectiveness are rare. The objectives of our study were to assess current acid-precipitation remediation programs in streams of the Allegheny Plateau ecoregion of West Virginia (USA), identify specific attributes that could and could not be fully restored, and quantify temporal trends in ecosystem recovery. We sampled water chemistry, physical habitat, periphyton biomass, and benthic macroinvertebrate and fish community structure in three stream types: acidic (four streams), naturally circumneutral (eight streams), and acidic streams treated with limestone sand (eight streams). We observed no temporal trends in ecosystem recovery in treated streams despite sampling streams that ranged from 2 to 20 years since initial treatment. Our results indicated that the application of limestone sand to acidic streams was effective in fully recovering some characteristics, such as pH, alkalinity, Ca2+, Ca:H ratios, trout biomass and density, and trout reproductive success. However, recovery of many other characteristics was strongly dependent upon spatial proximity to treatment, and still others were never fully recovered. For example, limestone treatment did not restore dissolved aluminum concentrations, macroinvertebrate taxon richness, and total fish biomass to circumneutral reference conditions. Full recovery may not be occurring because treated streams continue to drain acidic watersheds and remain isolated in a network of acidic streams. We propose a revised stream restoration plan for the Allegheny Plateau that includes restoring stream ecosystems as connected networks rather than isolated reaches and recognizes that full recovery of acidified watersheds may not be possible.