Planning the conservation of La Mauricie National Park's Greater Ecosystem
In the current context of global change, natural environments are facing a growing number of biological (insects) and climatic threats, in addition to their susceptibility to urban and agricultural development. The widespread degradation and loss of these environments, as well as the loss of connectivity between them, has been unprecedented over the last 50 years. Yet it is essential to maintain and improve ecological connectivity, not least to sustain biodiversity, promote the resilience of these environments and continue to benefit from ecosystem services.
The idea behind protecting ecological connectivity is to integrate a network of biological, climatic and natural/semi-natural components (e.g. agricultural environment), interconnected with habitat patches (good quality natural environment), buffer zones and spatially defined corridors. The presence of corridors and buffer zones is essential to enable movement between the various habitats. Maintaining these ecological networks is therefore central to a region's diversity and resilience.
Resilience refers to the ability of forest ecosystems to recover from disturbance. It is greatly influenced by diversity, since the more diversified the biological characteristics of the tree species that make up a forest ecosystem, the more differently they will react to threats and the more resilient they will be to a broad spectrum of disturbances.
In other words, improving the resilience of natural environments depends on maintaining diversity and connectivity between habitats. In this sense, protected areas and parks play a particularly important role in maintaining habitat connectivity, whether on a local or regional scale.
The aim of our study for Parks Canada was to assess ecological connectivity at the scale of La Mauricie National Park's Greater Ecosystem, and to draw up a portrait of the resilience of its forest stands. The results of this project are intended as a decision-making tool to guide conservation management in La Mauricie National Park. The overall conclusion is that it is necessary to develop a more territorial vision in order to more easily link the various parks together and thus ensure the maintenance of diversity, connectivity and resilience.
Connectivity and species movement within the territory
Five species were selected to study the park's connectivity. Their selection was based on three factors: 1. representativeness of a range of functional traits, 2. presence at the heart of environmental issues and 3. availability of data. Our team began by analyzing the habitat quality index to assess the area's ability to meet a species' basic needs (movement, feeding, reproduction). The index thus reflects the proportion of quality habitats present in the study area for each of the species studied:
Ashy salamander: 76%, enjoys moist, mature deciduous and mixed forests
Black bear: 75%, appreciates large tracts of deciduous or mixed forest and tolerates a wide range of environmental conditions.
Eastern wolf: 61%, appreciates vast expanses of deciduous or mixed forests (but very sensitive to human activity).
American marten: 59%, appreciates mature, dense, coniferous or mixed forests.
Wood turtle: 9.1%, located exclusively along the water network
Our team then carried out two connectivity analyses, highlighting hydrological and terrestrial corridors for species movement in the region. Our team developed a synthesis map superimposing the movement corridors of the five selected species. This map could be used to establish a network of interconnected protected areas within La Mauricie National Park's Greater Ecosystem, and to identify areas in the landscape that need to be restored to support species movement.
Summary map of node-to-node connectivity analysis superimposing movement corridors for 5 species
Conservation priorities based on connectivity analyses
Resilience and vulnerability of the forests of La Mauricie National Park
The assessment of functional diversity and the analysis of species vulnerability to biological and climatic threats provided guidelines and recommendations for park management to improve the resilience of its forests.
Functional diversity analysis is used to determine whether the biological characteristics of the tree species identified are sufficiently diverse, based on the principle that these characteristics determine how tree species will respond and adapt to environmental conditions.
The results show a heterogeneous distribution of functional diversity in the park's forests. However, there is a certain concentration of poorly diversified stands in the central and eastern parts of the park.
The vulnerability analysis highlights the potentially widespread impacts of Asian gypsy moth, Asian longhorned beetle and drought. Almost all forest stands could be subject to defoliation (leaf drop) by Asian gypsy moth. These defoliations could easily add to the water stress associated with the droughts forecast for the region.
Other climatic threats could constitute additional stress factors impacting on the ability of forests to recover from disturbances. These are fairly evenly distributed across forests, or of relatively low concern due to the low probability of prolonged events, or the vulnerability of forest species to these threats.
Distribution of stands according to their vulnerability to biological threats of concern for the region
Distribution of stands according to their vulnerability to climatic threats of concern for the region
Poorly diversified stands, vulnerable to threats and playing an important role in the connectivity of the territory
To better understand the impact of the vulnerability of forest stands to global change on connectivity within the park, the map showing the most at-risk stands (+75% of the vulnerable stand) was superimposed on the map prioritizing the movement corridors of the 5 species studied. As the southern part of the park's territory is highly anthropized, conservation priorities for connectivity are mainly found in the northern part of the territory (Figure 22). However, the results indicate that a greater proportion of low-diversity stands vulnerable to at least one threat affecting more than 75% of their area are found in the northeastern part of the territory.
The results conclude that interventions aimed at improving resilience should be prioritized in the northeastern sectors of the territory, since these forests are the least diverse, the most vulnerable to the threats of greatest concern, and the most important for connectivity.
Things to remember...
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Firstly, the park lies at the heart of a predominantly mixed forest region, with a concentration of human activity in the southern part of the territory, near Trois-Rivières. Forestry activity is significant in the northern part of La Mauricie National Park's Greater Ecosystem. The spatial distribution of land use is directly reflected in the mosaic of connectivity in the landscape; the general trend emerging from the analyses indicates an almost absolute break in habitat connectivity between the northern and southern portions of the territory, particularly for species such as the Eastern Wolf and American Marten. Although this trend is less pronounced for the wood turtle, the majority of watercourses of very high importance for the movement of this species are found in the northern part of the Greater La Mauricie National Park Ecosystem. This distinction in importance for connectivity can be attributed almost exclusively to human activity, since the southern part of the territory contains the highest concentration of urban and agricultural environments.
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The results also draw attention to the fact that La Mauricie National Park constitutes a focal point with neighbouring protected areas, and thus favours the movement of species within the Greater Mauricie National Park Ecosystem. Thus, land management practices aimed at maintaining and improving landscape connectivity (especially with the southern part) will also contribute to maintaining the regional network.
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The optimization of conservation priorities as carried out allows us to identify the natural environments that contribute most to connectivity according to the selected indicators. Such an analysis optimizes conservation planning compared to more conventional approaches, since it encompasses more parameters, which can contribute to the implementation of optimized and more ambitious conservation objectives. In the case of the present study, the results of the analyses carried out and the prioritization of habitats and movement corridors highlight the importance of the northern portion of the territory for directing current and future conservation efforts.
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The results of our analyses revealed that a greater proportion of low-diversity stands, vulnerable to at least one threat that could affect more than 75% of the stand, are found in the northeastern portion of the NMCP. However, the northern part of the territory has been identified as a conservation area to be prioritized due to the quality of its habitats and its important role in connectivity. It is therefore recommended that priority be given to interventions in the northern part of the NMP, based on a functional diversity approach, in order to improve the resilience of forest stands to global change. To achieve this, it would be important to start by identifying the most vulnerable stands and then prioritize interventions. The recommended silvicultural interventions are those that will promote the diversification and functional connectivity of forest stands. Finally, regular monitoring and awareness-raising campaigns are recommended to encourage users to participate and contribute to the prevention of biotic and abiotic threats.
