More than money: how multiple factors influence householder participation in at-source stormwater management

Urban stormwater run-off is a threat to stream ecosystems. New approaches to stormwater management aim to protect urban streams from such impacts, by retaining, treating and using stormwater at its source. As up to ～50% of runoff from urban surfaces comes from private property, fostering stormwater retention requires effective householder engagement. We evaluated householder participation in the Little Stringybark Creek project, a stormwater retrofit programme aimed at waterway protection, using qualitative enquiry through formal and informal interviews to identify factors that influenced participation. Participation was governed by multiple factors, with financial incentives and personal co-benefits of tanks primary motivators, while process complexity and distrust were primary barriers. Results suggest an approach combining education to encourage review of subjective norms and attitudes, with incentives to mitigate behavioural controls can transform public behaviour towards sustainable stormwater management.     

Phylogeny of Opsanus spp. (Batrachoididae) inferred from multiple mitochondrial-DNA sequences

 Species of the toadfish genus Opsanus are increasingly used as experimental organisms in biomedicine and evolutionary/ecological physiology. Despite their importance, little is known of the phylogenetic relationships among Opsanus species. DNA sequence data for portions of the mitochondrial 12S rRNA, cytochrome oxidase I and cytochrome b genes were generated and analyzed from the four recognized Opsanus species and three outgroup taxa. Results of these analyses indicate an evolutionarily rapid divergence of three lineages within the genus. O. beta and O. pardus were resolved within the same lineage, and could not be distinguished with these mitochondrial sequence data. These data and paleoclimatic theory support a hypothesis of speciation based on the formation of allopatric populations during periods of elevated water temperature in the northern Caribbean. Received: 6 July 1999 / Accepted: 15 March 2000     

The Clean Air Act Amendments and Motor Vehicle Inspection/Maintenance

Seventeen days of detailed measurements of NO, NO₂, O₃, HNO₃ and the frequency of NO₂ photolysis—j(NO₂)—were carried out in Claremont, CA, in September 1980. Under conditions when the rate of change of NO concentration is small, there must be a balance between formation and loss processes. In the classical photostationary state this balance is between NO₂ photolysis: NO₂ + hv → NO + O and reaction with ozone: NO + O₃ → NO₂ + O₂. The results show that the latter reaction with ozone is inadequate to balance the formation step; a significant contribution is required from another NO oxidation process, possibly peroxy radical oxidation. If so, the inferred concentration of peroxy radicals shows a diurnal variation, peaking around solar noon.     

Optimization of a horizontal-flow biofilm reactor for the removal of methane at low temperatures

Three pilot-scale, horizontal-flow biofilm reactors (HFBRs 1–3) were used to treat methane (CH₄)-contaminated air to assess the potential of this technology to manage emissions from agricultural activities, waste and wastewater treatment facilities, and landfills. The study was conducted over two phases (Phase 1, lasting 90 days and Phase 2, lasting 45 days). The reactors were operated at 10 °C (typical of ambient air and wastewater temperatures in northern Europe), and were simultaneously dosed with CH₄-contaminated air and a synthetic wastewater (SWW). The influent loading rates to the reactors were 8.6 g CH₄/m³/hr (4.3 g CH₄/m² TPSA/hr; where TPSA is top plan surface area). Despite the low operating temperatures, an overall average removal of 4.63 g CH₄/m³/day was observed during Phase 2. The maximum removal efficiency (RE) for the trial was 88%. Potential (maximum) rates of methane oxidation were measured and indicated that biofilm samples taken from various regions in the HFBRs had mostly equal CH₄ removal potential. In situ activity rates were dependent on which part of the reactor samples were obtained. The results indicate the potential of the HFBR, a simple and robust technology, to biologically treat CH₄ emissions.

Implications: The results of this study indicate that the HFBR technology could be effectively applied to the reduction of greenhouse gas emissions from wastewater treatment plants and agricultural facilities at lower temperatures common to northern Europe. This could reduce the carbon footprint of waste treatment and agricultural livestock facilities. Activity tests indicate that methanotrophic communities can be supported at these temperatures. Furthermore, these data can lead to improved reactor design and optimization by allowing conditions to be engineered to allow for improved removal rates, particularly at lower temperatures. The technology is simple to construct and operate, and with some optimization of the liquid phase to improve mass transfer, the HFBR represents a viable, cost-effective solution for these emissions.     

Alternatives to biodiversity offsets for mitigating the effects of urbanization on stream ecosystems

Globally, offset schemes have emerged in many statutory frameworks relating to development activities, with the aim of balancing biodiversity conservation and development. Although the theory and use of biodiversity offsets in terrestrial environments is broadly documented, little attention has been paid to offsets in stream ecosystems. Here we examine the application of offset schemes to stream ecosystems and explore whether they suffer similar shortcomings to those of offset schemes focused on terrestrial biodiversity. To challenge the applicability of offsets further, we discuss typical trajectories of urban expansion and their cascading physical, chemical and biological impacts on stream ecosystems. We argue that the highly connected nature of stream ecosystems and urban drainage networks can transfer impacts of urbanization across wide areas, complicating the notion of like‐for‐like exchange and the prospect of effectively mitigating biodiversity loss. Instead, we identify in‐catchment options for stormwater control, which can avoid or minimize the impacts of development on downstream ecosystems, while presenting additional public and private benefits. We describe the underlying principles of these alternatives, some of the challenges associated with their uptake, and policy initiatives being trialed to facilitate adoption. In conclusion, we argue that stronger policies to avoid and minimize the impacts of urbanization provide better prospects for protecting downstream ecosystems, and can additionally, stimulate economic opportunities and improve urban liveability.     

Synoptic evaluation of regional PM2.5 concentrations

By comparing short-term fluctuations in PM2.5 species concentrations among nearby air quality monitors and among species, it becomes possible to understand the regional and local events leading to higher concentrations. This approach was applied at thirteen sites in the Maryland area for the 2001–2006 timeframe in order to identify and explain the behavior of eighteen different analytes as well as the daily Air Quality Index.Findings included identification of local upwind events such as fireworks displays, construction and demolition, the spatial extent of sulfate, nitrate, and ammonium correlations between ground-level monitors, correlations between some crustal species to indicate similar emissions sources in urban areas, and indicators of particle adsorption as a rate-limiting step for certain species. For example, the bromine behavior suggests that bromine concentrations on particulate matter may be limited by the particle adsorption rate and thus show a dependence on the Air Quality Index measurements.     

Summer Transport Patterns Affecting the Mohave Power Project Emissions

The Mohave Power Project (MPP) is an isolated 1580-MW coal-fired electric generating plant located in Laughlin, NV. Laughlin is a small desert gambling town situated in the lower Colorado River Valley near the junction of three states: Nevada, California, and Arizona. The location of the MPP is approximately 115 km southwest of the western end of the Grand Canyon National Park and about 240 km southwest from the Grand Canyon Village. This paper describes the summer transport patterns of the MPP emittants using illustrated examples from the Project MOHAVE (Measurements of Haze and Visual Effects) 1992 summer intensive study. The intensive study lasted 50 days from mid-July through August and encompassed the major meteorological patterns associated with southwestern U.S. summer meteorology. The MPP emittants were transported toward the Grand Canyon (north to the northeast) during more than 80% of the total hours. Airflow was from the south most of the time due to a combination of the semi-permanent thermal low, differential heating between the Gulf of California and lower Colorado River Valley, and upslope heating of the southern and western slopes of the nearby Colorado Plateau.     

Quantifying changes to historic fish habitat extent on north coast NSW floodplains,Australia

Global degradation of coastal ecosystems is influencing the provision of ecosystem services, including fisheries maintenance services. Degradation of the Australian coastal zone and its resources following European occupation has been recognised for some time. This includes the loss of ecologically important coastal wetlands, which have strong trophic and habitat links to fisheries. In NSW, structural flood mitigation works are a principle driver of the decline of coastal wetlands; however, little action has been taken to quantify the extent of decline due to limited information of the pre-European settlement extent of coastal wetlands. We use spatial data sets in GIS to quantify prime fish habitat and calculate the loss of fish habitat for the large coastal floodplains of northern NSW, which are significant contributors to the commercial and recreational fisheries of NSW. The technique is validated by comparison with early maps of wetland distribution. We identified pre-European distribution of available fish habitat of approximately 477,000 ha, of which 87,000 ha was identified as prime fish habitat. Approximately 62,000 ha of prime fish habitat was impacted by drainage of the coastal floodplains in association with flood mitigation works which intensified in the mid-1950s and were largely completed by 1971, equating to a loss of approximately 72 % of prime fish habitat. The declining value of the ecosystem services provided by prime fish habitat following drainage is likely to be substantial. Some actions have taken place to restore the functions of this habitat although significant opportunities remain to reverse this decline through management actions that restore natural drainage and reinstate tidal exchange. These actions become even more important as pressures on coastal wetlands increase with climate change and associated sea-level rise.     

Identification of fungal proteases potentially suitable for environmentally friendly cleaning-in-place in the dairy industry

Fourteen fungi were screened for ability to produce proteases with activity on milk protein. The proteases produced were assessed on a lab-scale in terms of their potential suitability for cleaning-in-place (CIP) in the dairy industry. Cleaning performance was assessed by determining the ability of the enzymes to remove an industrial-like milk fouling deposit from stainless steel. Based on the results observed, the extracellular protease activity produced by Schizophyllum commune was selected as most suitable for potential CIP application. A CIP procedure involving a sodium carbonate rinse followed by enzymatic cleaning with this fungal enzyme activity was developed. Satisfactory cleaning, judged by quantification of residual organic matter and protein on the stainless steel surface after cleaning, was achieved using the developed CIP procedure at 40 °C. This CIP procedure, based on biodegradable enzymes working at low temperature is more environmentally favourable than conventional CIP methods using caustic based cleaning solutions at 70-80 °C. Potential environmental benefits of the developed enzymatic CIP procedure include reduced energy consumption, decreased chemical usage and a reduced requirement for pH neutralisation of the resultant waste prior to release.     

Impediments and Solutions to Sustainable,Watershed-Scale Urban Stormwater Management: Lessons from Australia and the United States

In urban and suburban areas, stormwater runoff is a primary stressor on surface waters. Conventional urban stormwater drainage systems often route runoff directly to streams and rivers, thus exacerbating pollutant inputs and hydrologic disturbance, and resulting in the degradation of ecosystem structure and function. Decentralized stormwater management tools, such as low impact development (LID) or water sensitive urban design (WSUD), may offer a more sustainable solution to stormwater management if implemented at a watershed scale. These tools are designed to pond, infiltrate, and harvest water at the source, encouraging evaporation, evapotranspiration, groundwater recharge, and re-use of stormwater. While there are numerous demonstrations of WSUD practices, there are few examples of widespread implementation at a watershed scale with the explicit objective of protecting or restoring a receiving stream. This article identifies seven major impediments to sustainable urban stormwater management: (1) uncertainties in performance and cost, (2) insufficient engineering standards and guidelines, (3) fragmented responsibilities, (4) lack of institutional capacity, (5) lack of legislative mandate, (6) lack of funding and effective market incentives, and (7) resistance to change. By comparing experiences from Australia and the United States, two developed countries with existing conventional stormwater infrastructure and escalating stream ecosystem degradation, we highlight challenges facing sustainable urban stormwater management and offer several examples of successful, regional WSUD implementation. We conclude by identifying solutions to each of the seven impediments that, when employed separately or in combination, should encourage widespread implementation of WSUD with watershed-based goals to protect human health and safety, and stream ecosystems.