Forest Plantations in Manabí (Ecuador): Assessment of Fragmentation and Connectivity to Support Dry Tropical Forests Conservation

Abstract

In many tropical regions, national forests plantation programs have been promoted. Those plantations frequently contribute to habitat changes. However, the associated effects of forest plantations on habitat fragmentation and landscape connectivity are unclear. From 2008 to 2018, we examined land use changes, plantations, and deforestation of the Manabí province (Ecuador) provided by the Ecuadorian Ministry of the Environment. Four scenarios were created: (i) land uses in 2008, (ii) land uses in 2018, (iii) land uses in 2018 without deforestation, and iv) land uses in 2018 including reforestation. Fragmentation and connectivity metrics were analyzed using ArcGisPro and Graphad 2.6 software, respectively. Puma yagouaroundi was selected as the reference species. At regional scale, forest plantations had a significant effect on land uses changes and fragmentation during the study period. Forests decreased from 33.7% to 32.4% between 2008 and 2018, although other natural land uses, mostly those involving shrubs, increased by almost double (from 2.4% to 4.6%). Most of the deforestation affected native forests during this period, and most reforested areas in 2018 covered former agricultural land. Fragmentation decreased in the number of patches and increased in the average patch size. When considering reforestation, deforestation was higher than the reforested area (58 km2 of difference), increasing the number of patches but with smaller size. Reforestation increased connectivity with a higher number of links and distance, particularly in central and extreme northeast areas of Manabí province. The scenario without deforestation also increased connectivity for Puma yagouaroundi in the west part of the Manabí province. Our findings suggest that forest plantations contribute to forest conservation by increasing the connectivity between fragmented patches.

Assessment of habitat connectivity in a highly fragmented ecosystem: The seasonal tropical dry forest in Ecuador

“…The cost assigned to each type of land cover was similar to that calculated by Navarro-Cerrillo et al (2022) and Quimis et al (2023) (Table 1). Links between patches of native dry forest were created by means of cumulative cost depending on the land cover (Table 1), with a complete link topology (all the links between patches are potentially taken into account), ignoring links crossing a patch and saving real paths (Clauzel et al, 2019).…”

“…An analysis of the links between habitat patches of native dry forest was then carried out, during which their number, their distance in metres and their distance in costs in the years 1990, 2000, 2008, and 2018 at the same three distances were calculated. Once the connectivity analyses had been conducted, components were identified within the study area (Urban & Keitt, 2001): a component TA B L E 1 Land cover proposed by the Ecuadorian Ministry of the Environment, the assigned cost of moving through them according to Navarro-Cerrillo et al (2022) and Quimis et al (2023) and their reclassification for land cover change. TA B L E 2 Description of connectivity metrics analysed according to Clauzel et al (2019) and ecological meaning according to bibliographic references.…”