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bioRxiv · 10.1101/2020.03.13.991372

Identifying priority connectivity in a tropical forest hotspot severely affected by land use changes

Oliveria-Junior, N. D.·Heringer, G.·Bueno, M. L.·Pontara, V.·Meira-Neto, J.
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Abstract

The probability that a propagule reaches a certain location where it can establish and persist is affected by the distance from the source. Fragmented landscapes often promote the isolation of habitats that hinder or impede the movement of species that affect their range distribution, even when environmental conditions are adequate. Studies that assess the connectivity of the landscape are essential to ensure that ecological conservation planning covers all vital processes that occur on a landscape scale. Based on the classification of land cover in the Rio Doce Basin - RDB, we used a habitat / non-habitat approach to assess RDB connectivity for tree species. Based on circuit theory, we built 6 surface models of resistance based on habitat and non-habitat areas. We performed the analysis using the GIS plug-in and Linkage Mapper to generate lest cost path maps. The RDB is very fragmented, but still has functionally connected regions. The west to nothwestern and southeastern portions of the basin are well-connected and demand conservation practices, while the center-north of the basin and the far southwest are regions with greater resistance to connectivity as a result of strong anthropic pressures that reduce forests, requiring intervention through restoration projects avoiding loss due to lack of connectivity. In addition, land reclamation projects in degraded areas must also be organized in the Linhares region, as it is inserted in a region of very high biodiversity with a high level of endemism and a high number of threatened species.

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Oliveria-Junior, N. D., Heringer, G., Bueno, M. L., Pontara, V., Meira-Neto, J.. 2020-03-15. Identifying priority connectivity in a tropical forest hotspot severely affected by land use changes. https://doi.org/10.1101/2020.03.13.991372

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