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Two large neighbouring watersheds, the Bowron (3420 km2) and Willow (2860 km2) situated in the central interior of British Columbia, Canada, were used to compare their hydrological responses to forest harvesting in snow-dominant environment. Both watersheds had experienced significant, comparative forest harvesting level. The long-term hydrometric and timber harvesting data (>50 years of records) were analysed using time series analysis to examine the hydrological impacts of forest harvesting. The hydrological variables including mean, peak and low flows over annual and seasonal scales (spring snowmelt, summer rain and winter base flow) were tested separately. Results showed that forest harvesting in the Willow watershed significantly increased annual and spring mean flows as well as annual and spring peak flows, whereas it caused an insignificant change on those hydrological variables in the Bowron watershed. The contrasted differences in hydrological responses are due to the differences in topography, spatial heterogeneity, forest harvesting characteristics and climate between two watersheds. The relative uniform topography and climate in the Willow watershed may promote hydrological synchronization effects, whereas larger variation in elevations, together with forest harvesting that occurred at lower elevations, may cause hydrological de-synchronization effect in the Bowron watershed. The contrasted results demonstrate that the effects of forest harvesting on hydrology in large watersheds are likely watershed specific, and any attempt to generalize hydrological responses to forest harvesting must be carried out with caution. A landscape ecological perspective is critically needed for future forest hydrology studies, particularly for large watersheds. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The article focuses on salmon populations in British Columbia from 1900 to 1945 and how forest regulations, clearcutting, and other environmental conditions impacted them. The author analyzes the relations between the logging industry and fisheries, explaining that disputes over natural resource jurisdiction between the two industries were commonplace. He discusses sources of salmon habitat degradation, explores streamside logging and how it impacted ecosystems, and explains Canadian environmental policies, including the Forest Act of 1912 and the federal Fisheries Act.

The article discusses research by biologists John Fryxell, Jim Baker, and team into the decline of woodland caribou (Rangifer tarandus caribou) in Ontario, Canada using population viability analysis (PVA) to identify potential causes and conservation remedies. Two ecotypes of Ontario caribou are described, one that migrates between tundra and boreal forest and one which remains in the boreal forest in every season. The caribou habitat has been altered by deforestation from logging and mining, as well as changes in forest composition caused by global warming. The PVA looked at factors such as increased competition between caribou and moose and predation by wolves as the species are driven into new habitats, parasitism by black flies, and caribou feeding on mosses and lichens.

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Abstract: There has been only one time-controlled study, in Canada, comparing the occurrence of bryophyte species in forests regenerating after wildfire with that in those regenerating after logging and regeneration burning. Previous work on vascular plants in Tasmanian tall open-forest dominated by Eucalyptus showed that filmy ferns were less common in areas that had been logged and regeneration burned than in areas burned by wildfire two decades after the events, which suggested that hygrophilous species, such as bryophytes, might be vulnerable to this silvicultural system. Bryophytes, vascular plants structural and environmental data were collected from 50 sites, which had been burned in wildfires or clearfelled and burned by prescribed fires 31–39 years previously. Eighteen percent of the vascular plant species for which it was possible to develop a multiple regression model had logging/wildfire as a component, whereas the equivalent figure for bryophytes was 17%. The negative effects of logging were concentrated on the more hygrophilous species, and the positive effects were concentrated on the basal area of tree species and some of the mosses dependent on them. We conclude that wildfire and logging followed by regeneration burning result in vegetation differences that last more than three decades after disturbance, that these differences are no more pronounced for bryophytes than for vascular plants, and that hygrophilous taxa are favoured more by wildfire than logging. [Copyright &y& Elsevier]

Habitat configuration has important implications for the persistence of faunal and floral populations at a variety of spatial scales. Forest harvesting alters habitat configurations. However, measuring and predicting such alterations remains challenging, in part because previously developed metrics of habitat configuration are often not statistically independent of habitat amount. Thus, their ability to measure independent effects of habitat configurations and habitat amount on ecosystem components such as wildlife populations has been limited. Here, we evaluate habitat configuration based on newly developed metrics that are independent of habitat amount but do not depend on regression residuals of abundance and configuration relationships on any population of landscapes. We use these new metrics to measure and predict changes in habitat configuration following forest harvesting in the boreal forest of Alberta, Canada. Our findings clearly demonstrate changes in habitat configuration resulting from forest harvesting can be predicted precisely with information about initial habitat patch structure and harvesting patterns. Because forest harvesting has significant implications for habitat configuration, accurately predicting these changes is critical for determining if forest harvesting strategies are sustainable for ecosystem components and processes. This study provides a set of novel, robust metrics for tracking landscape-scale changes in habitat configuration in harvested boreal forests. [ABSTRACT FROM AUTHOR]

We evaluated the cumulative effects of land use disturbance resulting from forest harvesting, and exploration and extraction of oil and gas resources on the occurrence and structure of stream fish assemblages in the Kakwa and Simonette watersheds in Alberta, Canada. Logistic regression models showed that the occurrence of numerically dominant species in both watersheds was related to two metrics defining industrial activity (i.e., percent disturbance and road density), in addition to stream wetted width, elevation, reach slope, and percent fines. Occurrences of bull trout, slimy sculpin, and white sucker were negatively related to percent disturbance and that of Arctic grayling, and mountain whitefish were positively related to percent disturbance and road density. Assessments of individual sites showed that 76% of the 74 and 46 test sites in the Kakwa and Simonette watersheds were possibly impaired or impaired. Impaired sites in the Kakwa Watershed supported lower densities of bull trout, mountain whitefish, and rainbow trout, but higher densities of Arctic grayling compared to appropriate reference sites. Impaired sites in the Simonette Watershed supported lower densities of bull trout, but higher densities of lake chub compared to reference sites. Our data suggest that current levels of land use disturbance alters the occurrence and structure of stream fish assemblages. [ABSTRACT FROM AUTHOR]

The article offers information related to the 1972 Planning Guidelines for Coast Logging Operations and the National Democratic Party (NDP) government's response to the forests and other natural resources in Canada. It relates the subject that Jeremy Wilson discussed regarding the necessity of understanding the environmental politics during the early 1970s period. It also highlights the response of the Guidelines, which represented the British Columbia Forest Service (BCFS) over the rising public discomfort over the ecological consequences of unrestrained clearcutting of trees.

Presents several news briefs about the environment as of October 1987. Community effort to reclaim land damaged by logging and mining in Sudbury, Ontario; A dragonfly sanctuary in Japan; Salmon net-pens spawn revolt in Washington State. More briefs.

The article reports on the move of Avrim Lazar, president of the Forest Products Association of Canada (FPAC), to urge the public to support the bid of the World Wildlife Fund (WWF) to end global deforestation. He also added that such challenge could extend to a campaign to stop illegal logging, which is said to contribute to deforestation. Lazar discussed Canada's environmental record and forestry industry.