Anàlisi preliminar de la percepció i la gestió de les invasions vegetals en espais naturals protegits de Catalunya

Abstract

Invasive exotic plants are considered to be one of the largest threats to native biodiversity. For this reason, we have undergone a compilation of data about the impacts and management strategies of invasive plants in some natural areas of Catalonia, which are considered representative for the ecosystems of this region. Our objectives are: to (1) evaluate the problem perception by public administrations, (2) identify those plants that represent a major threat according to environmental managers, (3) make an inventory of management strategies carried out in these natural areas, and finally (4) estimate the economic consequences of invasive plants management. The data has been obtained through the sending of questionnaires to environmental managers responsible for the management of invasive plants. We have performed more than 30 contacts, of which 67 % have identified plant invasions as a threat for native biodiversity in their natural areas. These respondents have considered that biological invasions occupy, in average, the fifth place in relation to other environmental problems of the region. They have cited a total of 61 problematic invasive plants in their areas of responsibility. The species mentioned in more cases have been Ailanthus altissima, followed by Cortaderia selloana, Buddleja davidii, Robinia pseudoacacia, Senecio inaequidens, Arundo donax, Carpobrotus edulis and Parthenocissus quinquefolia. Thirty-one of the 61 problematic invasive plants have been managed, being Ailanthus altissima the species managed in more places, followed by Carpobrotus edulis, Arundo donax and Cortaderia selloana. The control and eradication of these plants were the management strategies more applied in the studied areas, and they are also the most valuated by the respondents. A total of 151.020 $ have been invested for the management of invasive plants in the contacted natural areas. The species that has caused major management costs is Senecio inaequidens. Nonetheless, the exact costs of most of the applied management actions are unknown to the respondents therefore an accurate economic valuation is quite difficult to achieve.