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Museums and their roles as cultural institutions have evolved rapidly in the last 50 years. A growing trend toward broadened mandates and other factors have created resource challenges that encourage new opportunities. Although this paper focuses on natural history museums, similar arguments for co-staffing could be formulated for other museums. For natural history museums, the resource challenge extends to a dwindling number of systematics experts who are essential in acquiring specimens for the collection, creating new knowledge about them through research, and in providing information that is valuable to the full range of other museum programs. This paper reviews existing models for maintaining scientific expertise at museums, and details a new model to acquire and maintain scientific expertise through a case study at one of Canada's national museums and a local university. [ABSTRACT FROM AUTHOR]

Presents a study that determined the influence of spatial and temporal scale of acidification on the resilience of epilithic assemblages during chemical recovery of Canadian boreal lakes. Effects of anthropogenic acidification of boreal lakes on several environmental variables; Indicators of recovery in acidifed lakes; Comparison of experimental and atmospheric acidification of lakes; Details of study lakes and sampling protocols.

Studies the whole-lake algal responses to a century of acidic industrial deposition in the boreal lakes in Canada. Lack of data predating the onset of industrial pollution; Accounts on the loss of biodiversity on the productivity and stability of boreal lakes; Destabilization of the vital ecosystem functions.

Climate warming has been shown to increase the frequency of extreme weather effects on small lakes by increasing the variability of terrigenic inputs and surface water temperatures. We hypothesized that the effect of thermal variability on boreal plankton depends on dissolved terrigenic matter (i.e., temperature-terrigenic interaction). A two-factor mesocosm (1500-L capacity) experiment consisting of three terrigenic treatment levels (control, [-] runoff, [+] runoff) and three temperature treatment levels (control, warm, and cold) was conducted in triplicate for a total of 27 mesocosms deployed in Lake 302S of the Experimental Lakes Area in Canada. The warming treatment amplified the positive effect of terrigenic amendment on total phytoplankton biomass by stimulating large (>35-µm Greatest Axial Linear Dimension; GALD) taxa during the 50-d experiment. In comparison, removal of terrigenic matter increased the abundance of smaller (<35-µm GALD) phytoplankton along with copepods and cladocerans under cold and warm conditions, respectively. We also attempted to corroborate our experimental findings by comparing planktonic communities collected from reference Lake 239 during climatically contrasting summers between 1970 and 2001. Although planktonic communities in Lake 239 also differed significantly between years characterized by cold, wet vs. warm, dry ice-free conditions, their responses ran opposite to those detected during the experiment, highlighting the potential overriding importance of other scale-dependent factors (e.g., fish predation, vertical migration) mediating the effects of climate on lake communities. [ABSTRACT FROM AUTHOR]

Abstract: Characterization of the effects of cruise ship emissions on local air quality is scarce. Our objective was to investigate community level concentrations of fine particulate matter (PM2.5), nitrogen dioxide (NO2) and sulphur dioxide (SO2) associated with cruise ships in James Bay, Victoria, British Columbia (BC), Canada. Data obtained over four years (2005–2008) at the nearest air quality network site located 3.5km from the study area, a CALPUFF modeling exercise (2007), and continuous measurements taken in the James Bay community over a three-month period during the 2009 cruise ship season were examined. Concentrations of PM2.5 and nitrogen oxide (NO) were elevated on weekends with ships present with winds from the direction of the terminal to the monitoring station. SO2 displayed the greatest impact from the presence of cruise ships in the area. Network data showed peaks in hourly SO2 when ships were in port during all years. The CALPUFF modeling analysis found predicted 24-hour SO2 levels to exceed World Health Organization (WHO) guidelines of 20μgm−3 for approximately 3% of 24-hour periods, with a maximum 24-hour concentration in the community of 41μgm−3; however, the CALPUFF model underestimated concentrations when predicted and measured concentrations were compared at the network site. Continuous monitoring at the location in the community predicted to experience highest SO2 concentrations measured a maximum 24-hour concentration of 122μgm−3 and 16% of 24-hour periods were above the WHO standard. The 10-minute concentrations of SO2 reached up to 599μgm−3 and exceeded the WHO 10-minute SO2 guideline (500μgm−3) for 0.03% of 10-minute periods. No exceedences of BC Provincial or Canadian guidelines or standards were observed. [Copyright &y& Elsevier]

Particulate matter (PM) speciation data were collected between November 2004 and August 2006 in the rural valley area of British Columbia, Canada. Source apportionment of PM was performed using a receptor model, positive matrix factorization (PMF), to identify possible sources of PM and determine the influence of each identified source on local air quality. High concentrations of PM2.5 (<2.5μm) were observed in winter months with an average of 18μgm−3, while the average concentration in summer months was approximately 6μgm−3. PMF apportioned the PM2.5 mass into seven factors identified as Na-rich, secondary sulfate, wood burning, wood processing, crustal material, traffic, and winter heating. The most important sources affecting ambient air quality in the deep valley rural area were wood burning and winter heating factors. In winter the wood burning and winter heating sources accounted for approximately 31% and 43% of the total PM2.5 mass, respectively, indicating the significant influence of biomass burning in the rural area. The wood burning and winter heating factors were highly associated with high organic carbon and volatile organic compounds. The identity of the sources was further elucidated by exploring their relationship with other measured parameters; a correlation study was conducted to evaluate relationships between the sources, gaseous pollutants, and meteorological variables. [Copyright &y& Elsevier]