Since 2018, more than a hundred researchers, students and professionals from three Quebec universities – UQTR, Laval and McGill – have participated in research carried out within the Multidisciplinary Center of Expertise in Sustainable Coastal Management of the Lake Saint-Pierre. During a public event held today, these researchers delivered their findings and recommendations, with a view to establishing agriculture that respects the ecosystem of Lake Saint-Pierre and restoring priority environments. of the coastline.
Rebuilding a functional ecosystem
Overall, the Center emphasizes the need to protect and rehabilitate the natural environments of the coast of Lake Saint-Pierre. Nearly 3,800 hectares of wildlife habitats have been modified there since 1950, mainly for the benefit of agriculture. “It is essential to extend conservation efforts in order to better protect existing natural environments against any new pressure, to rehabilitate degraded environments and to increase the connectivity of these environments with the river,” underlines Stéphane Campeau, researcher at the “environment and wildlife” axis of the Pole and professor in the Department of Environmental Sciences at the University of Quebec at Trois-Rivières (UQTR).
The environments most conducive to the restoration of coastal ecosystem functions would be natural environments, old meadows and strips of perennial vegetation. A mosaic of these different environments would help maximize wildlife biodiversity. Bare soils or with little crop residue, which are harmful to the ecosystem, should be avoided. In low coastal areas, which are more frequently flooded, the Pole recommends a permanent vegetation cover offering better spawning habitat for fish in spring.
Regarding the water quality of the coast of Lake Saint-Pierre, it is affected by the erosion of agricultural soils and gullying. 2/3 of the sediment loads ending up in the coastline come from agricultural lands upstream. It would therefore be necessary to adequately protect the soils and banks against erosion not only on the coastline, but also in more than a hundred watersheds of small watercourses emptying directly into the coastline of Lake Saint-Pierre. . Respecting riparian zones, revegetation as well as the conservation of natural environments and wooded corridors are all possible solutions.
Gullying in the watershed of a tributary stream of Lake Saint-Pierre in Baie-du-Febvre. (Photo: Stéphane Campeau, 2019)
Review agricultural practices
The Pole’s work has revealed that the low-lying areas of the coast of Lake Saint-Pierre are the least productive from an agronomic point of view, especially during years of medium and high floods. In addition, the annual crops grown there have negative impacts on ecosystems, even when using improved managed agriculture aimed at better environmental benefits. In low coastal areas, it would therefore be preferable to opt for forms of cultivation allowing the maintenance of permanent vegetation of sufficient height and density in the fall.
“In higher areas of the coast, less often flooded, the management of annual crops must also be adapted. The agro-environmental practices to be favored would include tillage in the spring after the flood rather than in the fall, the planting of intercropping cover crops in corn and soybeans, as well as the establishment of strips of perennial vegetation in borders of watercourses and ditches along cultivated fields. These measures would promote the creation of a variety of habitats favorable to biodiversity,” mentions Caroline Halde, researcher in the “agriculture” axis of the Cluster and professor at the Faculty of Agricultural and Food Sciences of the ‘Laval University.
Trial of ryegrass, forage radish and hairy vetch intercropped in a corn field. (Photo: Caroline Halde)
Supporting farmers and pooling community efforts
According to the Pôle’s results, it appears that for the Quebec population, government intervention in favor of coastal rehabilitation would be considered legitimate. Furthermore, regardless of the adoption of improved practices, several agricultural producers mentioned the repurchase of their land in the coast as a possible solution.
Although a transitional regime, established in 2022, authorizes the practice of agriculture on the coast of Lake Saint-Pierre under certain conditions, this complicates environmental rehabilitation. Difficulties in dialogue between the different actors in the field and problems of governance are emerging. The absence of a global, long-term vision prevents the creation of a dynamic of collective commitment towards the preservation of the Lake Saint-Pierre ecosystem.
“We have observed that agricultural producers receive little support, in terms of financial assistance and agricultural advice, in the first steps leading them towards the adoption of improved and sustainable practices in the coast of Lake Saint-Pierre. In addition, the better the practices of agricultural producers from an environmental point of view, the greater their economic losses and their socio-technical challenges,” reports Julie Ruiz, researcher in the “socio-economics” axis of the Pole and professor in the Department. of environmental sciences from UQTR.
Flooding in Baie-du-Febvre, a municipality located on the south shore of Lake Saint-Pierre. (Photo: Pierre-André Bordeleau, 2019)
Avenues for action
The Pole’s final report includes several proposals aimed at facilitating the restoration of the Lake Saint-Pierre ecosystem and the establishment of sustainable agriculture. A progressive management approach is suggested, including several modest and concrete objectives likely to maintain the commitment of stakeholders and ensure a transition between today and tomorrow.
The members of the Pole also propose to rebuild the dialogue between the provincial government and the various stakeholders of Lake Saint-Pierre. Territorial governance must be improved to facilitate communications and coordination. The presence of a unifying, solid, legitimate organization with the necessary resources appears important. The latter would notably include an interministerial committee, a regional consultation table, a network of local committees and an independent scientific committee.
The Pole suggests focusing on a set of flexible solutions adapted to the ecological conditions and socio-economic realities of agricultural producers. To the latter, different solutions should be offered: repurchase of their land on a voluntary basis, financial assistance, peer groups on agricultural practices, expert agricultural advice in the integration of sustainable agricultural practices, etc.
To learn more about the findings and recommendations of the Pôle, you can consult the following website: www.uqtr.ca/polelsp.
Aerial view of Lake Saint-Pierre. (Photo: Julie Ruiz)
The Pole and Lake Saint-Pierre
Remember that the multidisciplinary center of expertise in sustainable management of the Lake Saint-Pierre coastline was created in July 2018 by the government of Quebec, with the granting of a budget envelope of $4.66 million to the three participating university establishments to the project. The Center’s research programming includes three axes to respond to the agricultural, ecological and socioeconomic challenges of Lake Saint-Pierre. Since the creation of the Center, the research team has collected and analyzed numerous samples (water, soil, animals, plants) and economic data. She also carried out agronomic trials and met with agricultural producers, to better understand the agroecosystem of Lake Saint-Pierre.
Taking environmental data in a flooded forest on the shore of Lake Saint-Pierre. (Photo: Gilbert Cabana)
Stretching nearly 30 km long and 13 km wide, Lake Saint-Pierre constitutes the last freshwater basin of the Saint Lawrence River upstream of the river estuary. It is distinguished by its very flat topography, which makes it the largest freshwater floodplain in Quebec. Its coastline, the area flooded on average every two years, is a hotspot for biodiversity and is part of the biosphere reserves designated by UNESCO. Made up of wetlands and cultivated land, the coastline of Lake Saint-Pierre is home to nearly 300 species of resident and migratory birds, 79 species of fish and 40 species of mammals. It represents an exceptional breeding, feeding and nesting environment for many of these species.
During periods of flooding, the surroundings of Lake Saint-Pierre constitute an important migratory stopover for the snow geese. (Photo: Julie Ruiz)
Information and interview coordination
Jean-François Hinse – Communications Advisor
Media Relations Manager
Communications and Alumni Relations Department – UQTR
Cell. : 819 244-4119
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