Context Maintaining connectivity in landscapes where natural ecosystems are quickly replaced by human land-uses is a challenge. To reduce the effects of habitat loss, ecological corridors have been proposed as a relevant tool for landscape planning. Objective We aimed to develop a spatial model to identify and prioritize riparian corridors to improve landscape connectivity. Methods The model considers the effect of the landuse/cover types and remaining forests on the movement capacity of a focal species sensitive to fragmentation. Since landscape elements act as barriers or promoters to ecological fluxes, suitability values were set according to the element's ability in providing habitat. The model recognizes the effect of the contact between associated elements along the riparian corridor's width and length and corrects their suitability. These procedures enabled the calculation of the Utility Factor, resulting in a measure of the quality of the corridor.
ResultsThe results show that the model assists the identification of the riparian corridor's sections where connectivity is hampered and management efforts are required to maintain landscape connectivity. In addition, it can be applied to select the corridors dominated by large forests, which could be designed for conservation purposes. The two study cases evidence that the model is flexible, adjustable to distinct landscapes, and the decision-maker's objectives. Conclusions We concluded that the proposed strategy helps decision-makers to prioritize the territories for managing or preserving connectivity. Finally, the method provides quantitative information that would not be perceived by just interpreting land-use/cover maps.
The selection of forest fragments for conservation is usually based on spatial parameters as forest size and canopy integrity. This strategy assumes that chosen fragments present high conservation status, ensuring biodiversity and ecological functions. We argue that a well-preserved forest fragment that remains connected by the landscape structure, does not necessarily hold attributes that ensure the presence of keystone species. We also discuss that the presence of keystone species does not always mean that it has the best conditions for its occurrence and maintenance. We developed a model to select areas in forest landscapes to be prioritized for protection based on suitability curves that unify and compare spatial indicators of three categories: forest fragment quality, landscape quality, and environmental conditions for the occurrence of a keystone species. We use a case study to compare different suitability degrees for Euterpe edulis presence, considered an important functional element in Atlantic Forest (São Paulo, Brazil) landscapes and a forest resource for local people. The results show that the identification of medium or advanced stage fragments as singular indicator of forest quality does not guarantee the existence or maintenance of this keystone species. Even in some well-preserved forest fragments, connected to others and with palm presence, the reverse J-shaped distribution of the population size structure is not sustained and these forests continue to be threatened due to human disturbances.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.