A comparison of sampling techniques and summary indices for assessment of water quality in the Yamaska River,Québec,based on benthic macroinvertebrates

The Yamaska River drainage basin in Quebec, Canada, is intensively farmed and heavily polluted with poorly treated domestic and industrial wastes. We investigated the responses of the resident and colonizing components of the benthic macroinvertebrate community to municipal/industrial versus agricultural pollution in the basin, and evaluated the performances of seven diversity and biotic indices for assessing water quality. Samples of riffle-dwelling, infaunal and colonizing invertebrates were collected from 13 stations representing a wide range of types and degrees of pollution using Surber, scoop and artificial substrate samplers. The data were summarized using the indices S (number of taxa), N (number of individuals), H (Shannon-Wiener's diversity index), D (Simpson's diversity index), BBI (Belgian Biotic Index), TBI (a modification of Hilsenhoff's Biotic Index), % CHIR (percentage of arthropods consisting of Chironomidae) and %OLIGO (percentage of total organisms consisting of Oligochaeta). Different components of the community generated somewhat different assessments and were, therefore, complementary. Community composition, expressed as the percentage of individuals contributed by major taxonomic groups, reflected the kinds of stresses at a station more consistently than did any of the indices. S and TBI came closest to ranking control, agricultural and municipal/industrial sites in accordance with our a priori classification, both between months and among sampling methods. %OLIGO usually separated municipal/industrial sites from control sites. Other indices were found to be less sensitive, accurate or temporally stable, or were otherwise inappropriate for use with certain sampling methods or for certain types of pollution. With most of our samples, all of the summary indices suggested that the impact of agricultural practices on stream ecosystems may be as severe as the impacts of municipal and industrial wastes.     

Mining taxation issues for the future

During the 1970s and 1980s the main concern of mining policies was to attract investment whilst at the same time balancing the interests of governments and companies. By the turn of the century a new spectrum of challenges faces governments and companies in the mining sector. The need for fiscal regimes to adapt to price cyclicity is to some extent superseded by the requirement that they adapt to a long-term decline of metal prices. The growing importance of environmental and community affairs in the mining sector will force governments to design coherent and comprehensive tax regulations to complement the wide range of initiatives being taken in these fields. Finally, the age-old problem of tax collection continues to raise its head in transition and developing economies.     

Geomorphology as an indicator of the biophysical vulnerability of estuaries to coastal and flood hazards in a changing climate

Climate change is increasing the need to characterise the vulnerability of coastal landscapes to coastal and flood hazards that result in erosion and inundation. Indices, such as the Coastal Vulnerability Index (CVI), have emerged as useful tools with which coastal managers can prioritise areas for further detailed assessment of vulnerability, risk, resilience and adaptation options. Approaches, such as the use of an index, efficiently characterise the vulnerability of linear, one-dimensional coastal features such as coastlines; however, they do not capture variability in coastal processes affecting more complex, non-linear features, such as estuaries, or interactive effects of coastal processes between linear (e.g. coastlines) and non-linear (e.g. estuaries) landforms. We present an approach that uses geomorphology to indicate biophysical vulnerability of estuaries to coastal and flood hazards. The approach is applied to the South Coast of NSW; a wave-dominated coastline of approximately 400 km length that contains more than 100 estuaries. We demonstrate the simplicity of the approach and its utility in identifying areas requiring higher resolution assessments. Although this approach does not include socio-economic factors, we demonstrate the capacity to incorporate socio-economic components of vulnerability using regional land use mapping. We infer that the most vulnerable estuaries are characterised by large catchment areas, broad estuarine valleys, mature stages of infill, or entrances oriented towards the prevailing wave direction. The area below 15 m elevation was identified as a robust indicator of the total area of vulnerability within a catchment. This approach can be applied to one-dimensional and more complex two-dimensional landscapes, such as estuaries; integrates varying sea-level rise projections; and incorporates a wider range of hazards that operate in the coastal zone.     

Aligning the logics of inquiry and action to address the biodiversity crisis

Despite an abundance of research reaffirming biodiversity's importance to the health of the planet and society, species continue to go extinct at an alarming rate. Why has continued research on the value of biodiversity not had the intended effect and what can be done about it? We considered biodiversity loss as a public value failure and the result of a misalignment between the logic of inquiry (which guides scientists) and the logic of action (which guides practitioners). We drew lessons from our own research to propose the creation of a national biodiversity strategy designed to link the logic of inquiry with the logic of action and coordinate the production of actionable conservation science and informed conservation action.     

Five approaches to producing actionable science in conservation

The knowledge produced by conservation scientists must be actionable in order to address urgent conservation challenges. To understand the process of creating actionable science, we interviewed 71 conservation scientists who had participated in 1 of 3 fellowship programs focused on training scientists to become agents of change. Using a grounded theory approach, we identified 16 activities that these researchers employed to make their scientific products more actionable. Some activities were more common than others and, arguably, more foundational. We organized these activities into 3 nested categories (motivations, strategies, and tactics). Using a co-occurrence matrix, we found that most activities were positively correlated. These correlations allowed us to identify 5 approaches, framed as profiles, to actionable science: the discloser, focused on open access; the educator, focused on science communication; the networker, focused on user needs and building relationships; the collaborator, focused on boundary spanning; and the pluralist, focused on knowledge coproduction resulting in valuable outcomes for all parties. These profiles build on one another in a hierarchy determined by their complexity and level of engagement, their potential to support actionable science, and their proximity to ideal coproduction with knowledge users. Our results provide clear guidance for conservation scientists to generate actionable science to address the global biodiversity conservation challenge.     

Web‐based automated remediation performance monitoring and visualization of contaminant mass flux and discharge

Environmental monitoring, data processing, and reporting methods are expensive, labor‐ and resource‐intensive, time‐consuming, and often inaccurate. An innovative project management platform was developed for integrating environmental monitoring sensors, telemetry, geographical information systems, models, and geostatistical algorithms for automatically generating contour maps and time‐stamped renderings of sensor attributes and multivariate analyses. More specifically, algorithms converting sensor‐derived head and solute concentration values allow for automated monitoring of mass flux and discharge to evaluate groundwater remediation system performance and contaminant discharges from aquifers to surface‐water receptors. Life‐cycle costs and carbon footprints were reduced due to the elimination of energy and labor expenditures associated with transportation, data collection, laboratory efforts, report generation, and information dissemination. A brief summary of two demonstrations of this sensor‐based water resources management application is presented. © 2011 Wiley Periodicals, Inc.     

Carbon--making the right choice for waste management in developing countries

Due to initiatives such as the clean development mechanism (CDM), reducing greenhouse gas emissions for a developing country can offer an important route to attracting investment in a variety of qualifying project areas, including waste management. To date CDM projects have been largely confined to schemes that control emission from landfill, but projects that avoid landfilling are beginning to be submitted. In considering the waste options which might be suitable for developing countries certain ones, such as energy from waste, have been discounted for a range of reasons related primarily to the lack of technical and other support services required for these more sophisticated process trains. The paper focuses on six options: the base case of open dumping; three options for landfill (passive venting, gas capture with flaring, and gas capture with energy production), composting and anaerobic digestion with electricity production and composting of the digestate. A range of assumptions were necessary for making the comparisons based on the effective carbon emissions, and these assumptions will change from project to project. The highest impact in terms of carbon emissions was from using a sanitary landfill without either gas flaring or electricity production; this was worse than the baseline case using open dumpsites. Landfills with either flaring or energy production from the collected gas both produced similar positive carbon emissions, but these were substantially lower than both open dumping and sanitary landfill without flaring or energy production. Composting or anaerobic digestion with energy production and composting of the digestate were the two best options with composting being neutral in terms of carbon emissions and anaerobic digestion being carbon negative. These generic conclusions were tested for sensitivity by modifying the input waste composition and were found to be robust, suggesting that subject to local study to confirm assumptions made, the opportunity for developing CDM projects to attract investment to improved waste management infrastructure is significant. Kyoto credits in excess of 1 tCO2e/t of waste could be realised.     

Effects of elevated atmospheric CO2 on invasive plants: comparison of purple and yellow nutsedge (Cyperus rotundus L. and C. esculentus L.)

The rise in atmospheric CO(2) concentration coupled with its direct, often positive, effect on the growth of plants raises the question of the response of invasive plants to elevated atmospheric CO(2) levels. Response of two invasive weeds [purple nutsedge (Cyperus rotundus L.) and yellow nutsedge (Cyperus esculentus L.)] to CO(2) enrichment was tested. Plants were exposed to ambient (375 micromol mol(-1)) or elevated CO(2) (ambient + 200 micromol mol(-1)) for 71 d in open top chambers. Photosynthetic rate did not differ between CO(2) treatments for either species. Conductance was lower in purple nutsedge and tended to be lower in yellow nutsedge. Purple nutsedge had higher instantaneous water use efficiency; a similar trend was noted for yellow nutsedge. Purple nutsedge had greater leaf area, root length and numbers of tubers and tended to have more tillers under high CO(2). In yellow nutsedge, only tuber number increased under CO(2) enrichment. Leaf dry weight was greater for both species when grown under elevated CO(2). Only purple nutsedge made seed heads; CO(2) level did not change seed head dry weight. Root dry weight increased under the high CO(2) treatment for purple nutsedge only, but tuber dry weight increased for both. Total dry weight of both species increased at elevated CO(2). Purple nutsedge (under elevated CO(2)) tended to increase allocation belowground, which led to greater root-to-shoot ratio (R:S); R:S of yellow nutsedge was unaffected by CO(2) enrichment. Findings suggest both species, purple more than yellow nutsedge, may be more invasive in a future high-CO(2) world.     

Native Grasses as a Management Alternative on Vegetated Closure Caps

Capped waste sites often are vegetated with commercial turf grasses to increase evapotranspiration and prevent erosion and possible exposure of the barrier. Fertilizer, frequent watering, and mowing may be required to establish the turf grass and prevent invasion by trees and shrubs. Oldfield vegetation of grasses and forbs is a possible sustainable alternative to turf grass communities. To determine if oldfield vegetation can establish on caps, we (1) compared establishment of a dominant oldfield grass and a commercial turf grass under different combinations of new closure cap management: spring or summer planting and presence or absence of amendments to alleviate drought (watering, mulch) or increase soil fertility (fertilizer, lime, a nitrogen-fixing legume); (2) surveyed existing caps to determine if oldfield species establish naturally; and (3) performed a greenhouse experiment to compare growth of two native grasses under low and amended (added water, soil nutrients) conditions. Both the commercial grass and oldfield species established under new cap conditions; fertilizer, water, and mulch improved vegetation establishment in spring or summer, but legumes decreased grass cover. In the greenhouse, both native grasses grew best with amendments; however, substantial stem and root length were obtained with no fertilizer and only once-weekly watering. Existing vegetated caps supported planted grasses and naturally established oldfield species. Overall, the results indicate native grasses can establish on new caps and oldfields can serve as a management model; further work is needed to determine the management strategy to maintain herbaceous vegetation and slow woody species invasion.     

Ambient air concentrations exceeded health-based standards for fine particulate matter and benzene during the Deepwater Horizon oil spill

The Deepwater Horizon oil spill is considered one of the largest marine oil spills in the history of the United States. Air emissions associated with the oil spill caused concern among residents of Southeast Louisiana. The purpose of this study was to assess ambient concentrations of benzene (n=3,887) and fine particulate matter (n=102,682) during the oil spill and to evaluate potential exposure disparities in the region. Benzene and fine particulate matter (PM2.5) concentrations in the targeted parishes were generally higher following the oil spill, as expected. Benzene concentrations reached 2 to 19 times higher than background, and daily exceedances of PM2.5 were 10 to 45 times higher than background. Both benzene and PM2.5 concentrations were considered high enough to exceed public health criteria, with measurable exposure disparities in the coastal areas closer to the spill and clean-up activities. These findings raise questions about public disclosure of environmental health risks associated with the oil spill. The findings also provide a science-based rationale for establishing health-based action levels in future disasters.

Implications: Benzene and particulate matter monitoring during the Deepwater Horizon oil spill revealed that ambient air quality was a likely threat to public health and that residents in coastal Louisiana experienced significantly greater exposures than urban residents. Threshold air pollution levels established for the oil spill apparently were not used as a basis for informing the public about these potential health impacts. Also, despite carrying out the most comprehensive air monitoring ever conducted in the region, none of the agencies involved provided integrated analysis of the data or conclusive statements about public health risk. Better information about real-time risk is needed in future environmental disasters.