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It has been suggested that without sufficient soil disturbance, harvest in boreal forested peatlands may accelerate paludification and reduce forest productivity. The objectives of this study were to compare the effects of harvest methods (clearcutting vs. careful logging) and season (summer vs. winter harvest) on black spruce regeneration and growth in boreal forested peatlands of eastern Canada, and to identify the soil variables that favour tree growth following harvest. Moreover, we sought to determine how stand growth following harvest compared with that observed following fire. The average tree height of summer clearcuts was greater than that of summer carefully logged stands and that of all winter harvested sites. Summer clearcutting also resulted in a higher density of trees > 3 m and > 4 m tall and in a 50% reduction in Rhododendron groenlandicum cover, a species associated with reduced black spruce growth. Height growth of sample trees was related to foliar N and P concentrations, and to soil total N, pH and available Ca and Mg but not to harvest method or season. Our results also indicate that summer clearcutting could produce stand productivity levels comparable to those observed after high-severity soil burns. These results suggest that summer clearcutting could be used to restore forest productivity following harvest in forested peatlands, and offer further support to the idea that sufficient levels of soil disturbance may be required to restore productivity in ecosystems undergoing paludification.

The publication of Quebec's National Policy on Architecture and Regional Planning (PNAAT) challenges geography in several respects. It is the result of an 18‐month development process and is built around the sustainable development paradigm. This storytelling is part of a generalized trend in planning. In Quebec, several public policies adopted since 2000 show a strong narrative. Consequently, it is necessary to address the nature of this narrative: is it the consolidation of the existing theoretical frame or a partial or total reframing of the paradigm developed in previous policies? In addition, what potential role will be played by the storytelling resulting from the PNAAT in terms of mobilizing stakeholders? These questions will lead us to compare various Quebec public policies, in terms of terminology as well as orientations and objectives. Our results illustrate the fact that the narrative of the PNAAT is in line with the territorial policies previously proposed. In addition, the call for sustainability and the fight against climate change has an obvious mobilizing power. [ABSTRACT FROM AUTHOR]

Altered temperature and precipitation regimes associated with climate change generally result in improved conditions for plant growth. For Arctic and sub-Arctic ecosystems, this new climatic context promotes an increase in primary productivity, a phenomenon often referred to as "greening". Although this phenomenon has been widely documented at the circumpolar scale, little information is available at the scale of plant communities, the basic unit of the Arctic and sub-Arctic landscape mosaic. The objectives of this study were (1) to quantify the variation of NDVI within the different plant communities of Nunavik (Québec, QC, Canada) in order to identify which ones contributed the most to the greening and (2) to identify the climatic and biophysical drivers of the greening. To do so, we used Landsat imagery to produce a time series of summer NDVI for the period 1984 to 2020. A fine-resolution map of Northern Québec vegetation was then overlaid on the time series of NDVI imagery and on maps of surficial deposits, topography, and gridded climate data to obtain information at the plant community level. We found that greening was more important in shrub-dominated communities, particularly near the tree line. Summer temperature, fall and winter precipitation, and surficial deposits were identified as drivers of greening. Through utilizing detailed vegetation maps to accurately quantify changes in Nunavik's plant communities, this study provides valuable insights into the dynamics of the region's ecosystem under rapid climate change. [ABSTRACT FROM AUTHOR]