Modeling the influence of forest cover on streamflows by different approaches.

Abstract There are many controversies about the effect of forest cover on basin streamflows. The objective of this paper was to use the Soil and Water Assessment Tool (SWAT) to provide hydrological modeling of streamflows of a Brazilian Atlantic Rainforest watershed, simulating land use change scenarios with increasing and decreasing forest cover. Regarding the afforestation scenarios, the influence of the geographic location on the afforestation was also evaluated through two approaches: a) a "random" approach (RA), in which the location of reforested areas does not matter; and b) an "imposed" approach (IA), in which the geographical positions of the afforestation are precisely defined. The RA results showed little tendency of reduction in the simulated average and minimum flows with the afforestation. The IA approach showed that the geographic position of afforestation did not significantly interfere in the average flows, but interfered in the simulated minimum flows. Afforestation concentrated in areas close to streams caused a reduction in minimum flows, while its concentration in the upper parts of the basin managed to increase them. Highlights • SWAT was used to provide hydrological modeling of Atlantic Forest watershed. • Afforestation and deforestation scenarios were simulated. • Random and imposed approaches to afforestation scenarios were evaluated. • Afforestation concentrated close to streams reduced minimum flows. • Afforestation in the upper parts of the basin managed minimum flows to increase. [ABSTRACT FROM AUTHOR]