The Fondazione Parco del Piano di Magadino has commissioned the firm Oikos – Consulenza e ingegneria ambientale Sagl of Bellinzona to design the enhancement interventions for the Vigna Lunga-Trebbione wetland of national importance, project no. 2305. The intervention was funded by the Canton, Municipalities, the Confederation, and the Blue Planet Virginia Böger X.X. Foundation.
The Vigna Lunga-Trebbione nature reserve represents what remains of an old oxbow lake of the Ticino River. The protected area extends between the flood-protection embankment and the main left-bank canal that marks its southern boundary. The rest of the perimeter is characterized by hay meadows and arable land. A small man-made pond is located in the center of the reserve, while a significant area in the western part has been converted into a storage site for plant material and a dirt yard.
In general, a progressive siltation of the marshy environments has been observed in the wetland, resulting in the replacement of hygrophilous species with mesophilous and ruderal species, leading to a simplification of habitat and floral diversity. This process has affected both forested and open areas and has been exacerbated by the penetration and spread of invasive neophytes, such as bamboo (Phyllostachis viridiglaucescens), which forms monospecific stands, and Himalayan balsam (Impatiens glandulifera), which is widespread in all types of habitats except for the most closed and shaded forest areas.
This state of degradation was already highlighted in the NR 297 datasheet, which is why the quality of the nature reserve is judged as insufficient. The presence of a large destroyed sector, the absence of trophic buffer zones, the high degree of siltation, and the presence of a body of water that is not very functional for the reproduction of amphibians (due to the presence of fish) are heavily penalizing elements. Furthermore, the management of the drainage canal crossing the reserve is not adequate for nature conservation purposes.
