Parsing participation: models of engagement for outcomes monitoring in urban stewardship

Few urban environmental stewardship, or civic ecology, practices monitor their impacts on local communities and ecosystems. This lack of monitoring prevents lay stewards from adapting their practices based on outcomes. For those that do collect data on their practices, we see different forms of practitioner engagement in outcomes monitoring. We categorise these different forms of engagement according to five published models of public participation in scientific research, revealing different strategies for collecting and analysing data towards adaptive co-management in urban ecosystems. We propose two broad strategies for expanding outcomes monitoring in these contexts: creating openly accessible tools and protocols for do-it-yourself inquiry and supporting more resource-intensive partnerships between practitioners and scientists for more complex forms of outcomes monitoring.     

Carbon Monoxide in an Urban Environment: Application of a Receptor Model for Source Apportionment

During the winter of 1985-86 the authors took 6-h integrated air samples and measured the concentrations of carbon monoxide and other gases at a residential site in Olympia, Washington. The 6-h average concentrations were between about 0.2 and 3.2 ppmv. For each 6-h period the observed concentration of CO was apportioned among its sources which were residential wood burning and automobiles. Small and generally insignificant amounts of CO were also observed from unidentified sources. A chemical mass balance (CMB) was formulated and applied to apportion the observed CO among its sources. Methylchloride (CH₃CI), in excess of background levels, was used as a unique tracer of wood burning and excess hydrogen (H₂) served as a tracer of CO from automobiles. The source emission factors to carry out the calculations were estimated from other experiments. The results showed that in Olympia, wood burning can often contribute as much CO as automobiles during winter. The maximum 6-h average contribution of CO from wood burning was about 2 ppmv and from automobiles it was 2.2 ppmv, and the average ambient concentration was about 1 ppmv. When pollution from wood burning was present, it contributed 0.5 ppmv on average while automobiles also contributed 0.5 ppmv. Unidentified sources contributed 0.1 ppmv and the background level was 0.15 ppmv. During the winter many times wood burning did not affect CO concentrations, while CO from automobiles was always present. On average, during the winter, automobiles contributed some 50 percent of the CO mass to the lower urban atmosphere and wood burning contributed about 30 percent. Diurnal cycles became evident in the calculated concentrations of CO from wood burning and automobiles even though the measured concentrations did not show strong diurnal variations. Wood burning contributed most during evening and nighttime and very little during the day, while automobiles contributed most during the morning and evening hours and very little at night. These patterns lend support to the accuracy of the model and source emission factors since they are as expected from the diurnal variations of the sources and atmospheric mixing.     

Effect of Fuel Properties on Mutagenic Activity in Extracts of Heavy-duty Diesel Exhaust Particulate

The effect of varying fuel properties on the emission of mutagenic materials was studied in diesel exhaust particles from a heavy duty engine run under transient speed and load conditions while using nine fuels varying in aromatics, sulfur and boiling point. Mutagenic activity of the soluble organic fraction (SOF) of the particulate was determined using the Ames Salmonella test system with strain TA98 with and without S9 activation. Increasing mutagenic activity relative to fuel consumed (mutants/lb fuel) or to engine work output (mutants/hp-h) was correlated with increasing fuel aromatics (p < 0.05), but not with fuel sulfur. Increased fuel sulfur levels were correlated with increased amounts of SOF but with decreasing mutagenic activity of the SOF (mutants/microgram SOF) (p < 0.05). As a result, mutants/hp-h were essentially the same for high- and low-sulfur fuels with high aromatics. No association was found between the fuels’ boiling points and the mutagenic activity of the SOF. Mutagenic activity with S9 was generally lower than without, but the correlations were not changed.     

Screening of seaweeds in the East China Sea as potential bio-monitors of heavy metals

Environmental Science and Pollution Research - Seaweeds are good bio-monitors of heavy metal pollution and have been included in European coastal monitoring programs. However, data for seaweed...     

Primary organic pollutants in New Zealand urban aerosol in winter during high PM10 episodes

In the two biggest New Zealand cities, Auckland and Christchurch, the mass concentration of the PM10 atmospheric aerosol can exceed the 50 microg m(-3) 24 h health guideline in winter. This high pollution level is thought to be caused mainly by old-fashioned domestic heating systems based on wood combustion. Therefore the chemistry of the carbonaceous aerosol has been investigated in several high-pollution level urban situations in order to assess the origin of the pollution. All the high concentration organic tracers, including levoglucosan and dehydroabietic acid, were characteristic for biomass burning. The findings have confirmed via advanced chemical analytical methods that domestic heating can be the main contributor to the high level of wintertime pollution, especially in Christchurch. The results are of great importance in supporting the ambition of authorities and environmental associations to change the domestic heating regimes.     

Field verification of sound attenuation modeling and air emission testing in support of missile motor disposal activities

The U.S. Department of Defense-approved activities conducted at the Utah Test and Training Range (UTTR) include both operational readiness test firing of intercontinental ballistic missile (ICBM) motors, as well as the destruction of obsolete or otherwise unusable ICBM motors through open burn/open detonation (OB/OD). Within the Utah Division of Air Quality, these activities have been identified as having the potential to generate unacceptable noise levels, as well as significant amounts of volatile organic compounds (VOCs). Hill Air Force Base, UT, has completed a series of field tests at the UTTR in which sound-monitoring surveillance of OB/OD activities was conducted to validate the Sound Intensity Prediction System (SIPS) model. Using results generated by the SIPS model to support the decision to detonate, the UTTR successfully disposed of missile motors having an aggregate net explosive weight (NEW) of 81,374 lb without generating adverse noise levels within populated areas. In conjunction with collecting noise-monitoring data, air emissions were collected to support the development of air emission factors for both static missile motor firings and OB/OD activities. Through the installation of 15 ground-based air samplers, the generation of combustion-fixed gases, VOCs, and chlorides was monitored during the 81,374-lb NEW detonation event. Comparison of field measurements to predictions generated from the US Navy energetic combustion pollutant formation model, POLU4WN, indicated that, as the detonation fire ball expanded, organic compounds, as well as CO, continued to oxidize as the combustion gases mixed with ambient air. VOC analysis of air samplers confirmed the presence of chloromethane, vinyl chloride, benzene, toluene, and 2-methyl-1-propene. Qualitative chloride analysis indicated that gaseous HCl was generated at low concentrations, if at all.     

Organochlorine concentrations, reproductive physiology, and immune function in unique populations of freshwater Atlantic stingrays (Dasyatis sabina) from Florida's St. Johns River

Within the past decade, reproductive and health disorders have been reported to occur in unique populations of Atlantic stingrays (Dasyatis sabina) inhabiting certain components of Florida's St. Johns River. Since these irregularities are consistent with the alleged effects of organochlorine (OC) contaminant exposure in other Florida wildlife, the goal of this study was to examine possible associations between OC concentrations and reproduction and/or immune function in stingrays from this river system. Liver concentrations of 30 OC pesticides/pesticide metabolites and total polychlorinated biphenyls (PCBs) were measured and compared in D. sabina collected from four central Florida lakes of the St. Johns River: Lake George, Lake Harney, Lake Jesup, and Lake Monroe. Reproductive biology, serum testosterone and 17beta-estradiol concentrations, and circulating white blood cell counts were examined and compared in stingrays from lakes that were determined to contain low (Lake George), intermediate (Lake Monroe), and high (Lake Jesup) levels of pesticide contamination, based on the results of liver OC assessments. Successful breeding occurred in Lake Jesup stingrays, indicating that the degree of OC accumulation in these animals is not high enough to cause reproductive impairment. However, elevated serum steroid concentrations and white blood cell counts were observed in Lake Jesup stingrays, suggesting that endocrine and immune function may be altered in these animals due to OC exposure and/or other, as yet unknown, ecological factors. Inconsistencies in the reproductive success of Lake Monroe stingrays were observed, confirming earlier reports of reproductive complications in this sub-population. Based on these findings, previous occurrences of reproductive failure in St. Johns River stingrays may be due to environmental factors other than OC exposure.     

Negative effects of stress-resistant drift algae and high temperature on a small ephemeral seagrass species

Seagrasses are threatened by multiple anthropogenic stressors, such as accumulating drift algae and increasing temperatures (associated with eutrophication and global warming, respectively). However, few seagrass experiments have examined whether exposure to multiple stressors causes antagonistic, additive, or synergistic effects, and this has limited our ability to predict the future health status of seagrass beds. We conducted a laboratory experiment to test whether abundance of Gracilaria comosa (3 levels; 0, 1.2, and 3.4 kg WW m⁻²), an algae that is resistant to wide environmental fluctuations (e.g. light, temperature, salinity, and oxygen levels), has negative effects on the small ephemeral seagrass, Halophila ovalis and whether the effects are exacerbated by high temperature (3 levels; 20, 25, and 30°C). We found an additive negative effect of the two stressors when tested simultaneously on 14 seagrass performance measures, with most data variability explained by the drift algae. For the individual plant performance measures (above- and below-ground growth and mortality, leaf area, internode distance, and root length and root volume), we found 5 additive effects, 4 synergistic effects, and 5 effects that were significant only for drift algae. We also documented a significant additive effect of drift algae and temperature on dissolved porewater sulphide (DS). A follow-up correlation analysis between DS and the 14 plant performance measures revealed significant or near-significant linear correlations on 9 of these responses (above- and below-ground growth, leaf area and weight, leaf mortality, and internode distance). In summary, we showed (a) that a stress-resistant drift algae can have strong negative effects on a small ephemeral seagrass, (b) this negative effect can increase both additively and synergistically with increasing temperature depending on performance measure, and (c) the negative effects may be mediated by a build-up of porewater DS. An implication of our findings is that resource managers aiming to preserve healthy seagrass beds in an almost certain future warmer world should increase efforts to keep drift algae populations low.     

Lead speciation in indoor dust: a case study to assess old paint contribution in a Canadian urban house

Residents in older homes may experience increased lead (Pb) exposures due to release of lead from interior paints manufactured in past decades, especially pre-1960s. The objective of the study was to determine the speciation of Pb in settled dust from an urban home built during WWII. X-ray absorption near-edge structure (XANES) and micro-X-ray diffraction (XRD) analyses were performed on samples of paint (380–2,920 mg Pb kg⁻¹) and dust (200–1,000 mg Pb kg⁻¹) collected prior to renovation. All dust samples exhibited a Pb XANES signature similar to that of Pb found in paint. Bulk XANES and micro-XRD identified Pb species commonly found as white paint pigments (Pb oxide, Pb sulfate, and Pb carbonate) as well as rutile, a titanium-based pigment, in the <150 μm house dust samples. In the dust fraction <36 μm, half of the Pb was associated with the Fe-oxyhydroxides, suggesting additional contribution of outdoor sources to Pb in the finer dust. These results confirm that old paints still contribute to Pb in the settled dust for this 65-year-old home. The Pb speciation also provided a clearer understanding of the Pb bioaccessibility: Pb carbonate > Pb oxide > Pb sulfate. This study underscores the importance of taking precautions to minimize exposures to Pb in house dust, especially in homes where old paint is exposed due to renovations or deterioration of painted surfaces.