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[1] Mean May-September Potomac River streamflow was reconstructed from 950-2001 using a network of tree ring chronologies (n ¼ 27) representing multiple species. We chose a nested principal components reconstruction method to maximize use of available chronologies backward in time. Explained variance during the period of calibration ranged from 20% to 53% depending on the number and species of chronologies available in each 25 year time step. The model was verified by two goodness of fit tests, the coefficient of efficiency (CE) and the reduction of error statistic (RE). The RE and CE never fell below zero, suggesting the model had explanatory power over the entire period of reconstruction. Beta weights indicated a loss of explained variance during the 1550-1700 period that we hypothesize was caused by the reduction in total number of predictor chronologies and loss of important predictor species. Thus, the reconstruction is strongest from 1700-2001. Frequency, intensity, and duration of drought and pluvial events were examined to aid water resource managers. We found that the instrumental period did not represent adequately the full range of annual to multidecadal variability present in the reconstruction. Our reconstruction of mean May-September Potomac River streamflow was a significant improvement over the Cook and Jacoby (1983) reconstruction because it expanded the seasonal window, lengthened the record by 780 years, and better replicated the mean and variance of the instrumental record. By capitalizing on variable phenologies and tree growth responses to climate, multispecies reconstructions may provide significantly more information about past hydroclimate, especially in regions with low aridity and high tree species diversity.

Questions: What were the characteristics of pre-Anglo-American (reference) forests before logging, grazing and fire exclusion, and how have they changed? What were the structural characteristics of canopy and surface fuels and potential fire behaviour in reference forests, and how do they compare to contemporary forests? How might information from reference conditions be used to inform current restoration and management practices?Location: Lake Tahoe Basin in the Sierra Nevada, California and Nevada, USA.Methods: Tree species composition, size structure, basal area, density, surface and canopy fuels, and potential fire behaviour were quantified for reference and contemporary conditions in 32 stands. This was accomplished by integrating field measurements and dendroecological techniques with vegetation and fire behaviour simulation models.Results: Contemporary Jeffrey pine and mixed conifer forests had more trees, more basal area, smaller trees and a different size structure than the reference forest. Contemporary red fir and lodgepole pine forests also had more and smaller trees, but basal areas were similar to the reference. Red fir forests also shifted in composition towards lodgepole pine. Vegetation and fire models indicate that contemporary Jeffrey pine and mixed conifer forests have higher flame length, rates of spread, lower crowning and torching indices, and more passive crown fire than the reference forests. In contrast, contemporary red fir and lodgepole pine forests only had lower crowning and torching indices, and flame length and rate of spread were only higher with extreme weather and high surface fuel load.Conclusions: Contemporary Jeffrey pine and mixed conifer forests deviate the most from the reference, and restoration objectives for these forests should emphasize density and basal area reduction of smaller diameter stems. Restoration objectives for red fir should shift species composition and reduce basal area by thinning smaller diameter lodgepole pine. For lodgepole pine forests, restoration objectives should include reduction of density and basal area of smaller diameter stems. Fire or other surface fuel treatments will be needed in all the forests to maintain lower fuel loads, albeit at different time intervals.

In the early twenty-first century, environmentally friendly accounting practices in the creative industries were confined to site-specific budgets of individual films or studio operations. Any external environmental costs were either ignored or written off as too hard to measure. This chapter considers the media's future by imagining a new kind of accountancy freed from the bonds of corporate media. Richard Maxwell and Toby Miller have devised an imaginary world where accountants, imbued with the values of green citizenship, set off on a quest to uncover the environmental and labor conditions within the global supply chain of consumer electronics and information and communication technologies. This speculative fiction helps the authors conjure up conditions in which media producers and media studies scholars address human-centric despoliation of the Earth's ecosystems and the toxic exploitation of media workers.