The influence of human activity patterns on personal PM exposure: a comparative analysis of filter-based and continuous particle measurements

Particulate matter (PM) exposure data from the U.S. Environmental Protection Agency (EPA)-sponsored 1998 Baltimore and 1999 Fresno PM exposure studies were analyzed to identify important microenvironments and activities that may lead to increased particle exposure for select elderly (>65 years old) subjects. Integrated 24-hr filter-based PM2.5 or PM10 mass measurements [using Personal Environmental Monitors (PEMs)] included personal measurements, indoor and outdoor residential measurements, and measurements at a central indoor site and a community monitoring site. A subset of the participants in each study wore passive nephelometers that continuously measured (1-min averaging time) particles ranging in size from 0.1 to approximately 10 microm. Significant activities and locations were identified by a statistical mixed model (p < 0.01) for each study population based on the measured PM2.5 or PM10 mass and time activity data. Elevated PM concentrations were associated with traveling (car or bus), commercial locations (store, office, mall, etc.), restaurants, and working. The modeled results were compared to continuous PM concentrations determined by the nephelometers while participants were in these locations. Overall, the nephelometer data agreed within 6% of the modeled PM2.5 results for the Baltimore participants and within approximately 20% for the Fresno participants (variability was due to zero drift associated with the nephelometer). The nephelometer did not agree as well with the PM10 mass measurements, most likely because the nephelometer optimally responds to fine particles (0.3-2 microm). Approximately one-half (54 +/- 31%; mean +/- standard deviation from both studies) of the average daily PM2.5 exposure occurred inside residences, where the participants spent an average of 83 +/- 10% of their time. These data also showed that a significant portion of PM2.5 exposure occurred in locations where participants spent only 4-13% of their time.     

Educating for our environment: an Australian experience

This paper examines how some of the principles of environmental education have been taken up in environmental strategies and activities in Victoria, Australia. The focus is upon the efforts of the State Government-funded Victorian Environmental Education Council (VEEC) to encourage the development of environmental education in sectors and organizations outside the formal education sector and not usually associated with either the environment or education. The relative success of initiatives fostered in marginalized community sectors and in the private industry sector are discussed. Following the abolition of the VEEC (late 1993) with a change of government, questions are raised about the sustainability of environmental reform agendas in the public political domain. In view of the fragility of sympathetic political environments, it is argued, that for environmentally sustainable development a broader commitment to social justice and social change must be fundamental to environmental education principles and processes to both include all sections of the community and, also, to actually change who makes decisions and how and where they are made.Jeannie Rea lectures in environmental policy and polities at Victoria University of Technology, Victoria, Australia. She was the Trades Hall Council representative on the Victorian Environmental Education Council and worked with others, on a publication chronieling exemplary environmental education projects in Victoria.     

Water-Quality Performance of a Constructed Stormwater Wetland for All Flow Conditions1

Wadzuk, Bridget M., Matthew Rea, Gregg Woodruff, Kelly Flynn, and Robert G. Traver, 2010. Water-Quality Performance of a Constructed Stormwater Wetland for All Flow Conditions. Journal of the American Water Resources Association (JAWRA) 46(2):385-394. DOI: 10.1111/j.1752-1688.2009.00408.x Abstract: Results from a multiyear study demonstrate that a constructed stormwater wetland (CSW) improves urban stormwater runoff quality mitigating downstream impacts. Best management practices, such as CSWs, can comprehensively treat the various scales of stormwater runoff issues. Discrete sample analysis was used to investigate the CSW effect for storm events and base-flow periods on water-quality parameters [i.e., total suspended solids, total dissolved solids, total nitrogen, phosphorous (total and reactive), chloride, heavy metals (zinc, lead, and copper), and Escherichia coli]. The primary finding was that stormwater sediment load was removed through the CSW for all flow conditions during all seasons. The mechanisms responsible for the removal of suspended solids, including slower flow velocity, longer retention times, and vegetative contact, also reduced the mass of nutrients discharged downstream throughout the year. Exceedance probabilities were used to evaluate the expected pollutant reductions of nutrients and to incorporate the effect of natural flow variation on quality. Other findings included the observation that there was no significant difference in the performance of the CSW over two-year-long periods four years apart, indicating that a CSW is effective for an extended period.     

Road and Rail Side Vegetation Management Implications of Habitat Use by Moose Relative to Brush Cutting Season

Plants cut at different times produce resprouts that vary in their nutritional value relative to when they are cut. To determine how vegetation management in transportation (road and rail) corridors at different times of the year could influence browse quality in the years following cutting, and how this could potentially influence encounters between herbivores and vehicles, we undertook a 3-year study. In 2001, at a wildlife viewing area near Prince George, British Columbia, Canada, we established a control area and treatment areas where shrubs and trees that are used as food by moose (Alces alces) were cut at the beginning of June, July, August, September, and October. In the fall, moose were most often observed browsing the resprouts of plants cut in August (years 1 and 2 post-treatment) and September (year 3). Cumulative winter track counts were highest in the uncut control area in the years following cutting. Spring pellet counts revealed that most pellets were deposited in the uncut (years 1 and 2) and August-cut (year 3) areas during winter. With the exception of the first year after cutting, browse removal by moose was highest for plants cut later in the growing season. Overall, our findings suggest that following cutting, plants cut later in the year are selected more often by moose relative to those cut earlier. To reduce browse use of corridor vegetation in areas where concerns for moose-vehicle collisions exist, we recommend that vegetation maintenance activities be conducted in the early summer months of June and July.     

NHDPlusHR: A National Geospatial Framework for Surface‐Water Information

The U.S. Geological Survey is developing a new geospatial hydrographic framework for the United States, called the National Hydrography Dataset Plus High Resolution (NHDPlusHR), that integrates a diversity of the best‐available information, robustly supports ongoing dataset improvements, enables hydrographic generalization to derive alternate representations of the network while maintaining feature identity, and supports modern scientific computing and Internet accessibility needs. This framework is based on the High Resolution National Hydrography Dataset, the Watershed Boundaries Dataset, and elevation from the 3‐D Elevation Program, and will provide an authoritative, high precision, and attribute‐rich geospatial framework for surface‐water information for the United States. Using this common geospatial framework will provide a consistent basis for indexing water information in the United States, eliminate redundancy, and harmonize access to, and exchange of water information.     

Influence of Cutting Time on Brush Response: Implications for Herbivory in Linear (Transportation) Corridors

An experiment was conducted to determine the influence the time of brush-cutting can have on plant regrowth and attractiveness to herbivores that browse in linear corridors. The influence of cutting time on leaf flush and senescence, shoot morphometry, and biomass was measured for 3 consecutive years after initial brush-cutting. Results indicate that morphological and phenological attributes of three woody deciduous plants were influenced by the timing of brush-cutting for up to 3 years after initial cutting. Brush-cutting generally stimulated plants to produce larger than normal shoots and delay leaf senescence. The degree to which plants were affected, however, varied with the timing of initial cutting and the species in question. Generally, plants cut later in the year resprouted more vigorously and were taller in the third year after cutting but produced less overall biomass than when cut earlier. In the years following brush-cutting, plants cut earlier flushed leaves earlier in the spring but delayed leaf senescence in the fall when compared to uncut controls. Results of these trials suggest that brush-cutting time influences plant response and several plant attributes known to influence plant attractiveness to moose and other herbivores. We therefore recommend that roadside and railside vegetation management plans consider the influence of cutting time on plant regrowth. Such considerations can ensure that brush is cut to reduce the attractiveness of plant regrowth in these linear corridors, reduce the utilization of such brush by herbivores, and, as such, mitigate collision risk between motorists and herbivores such as moose.