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Forest and landscape restoration in the tropics is often undertaken by groups of smallholders and communities whose livelihoods are primarily agricultural and forest-based. In the Philippines, the implementation of forest restoration programs involving people’s organizations showed mixed results. We present a case study of a pilot community-based forest restoration project that was undertaken in Biliran Province to understand the impediments, and pilot test interventions to improve restoration outcomes. The project was designed using systems thinking, employing smallholder-based best-practice, and applying the principles of a participatory approach. The results revealed that the initial participation of smallholders is mostly driven by short-term financial incentives. However, long-term commitment to managing the trees is attributed mainly to sustainable livelihood, land and tree rights, equitable sharing of benefits, strong leadership, effective governance and improved human and social capitals. The support of extension officers, use of high-quality seedlings, and participation of women are essential for community-based forest restoration success. Key lessons from our research could contribute to fulfilling the forest and landscape restoration commitments of developing countries in the tropics.

Reforestation of degraded grasslands can increase the soil hydraulic conductivity and number of preferential flow pathways. However, it is not clear to what extent these changes affect streamflow responses and whether this depends on the event size. We, therefore, studied the hydrological response of two small catchments near Tacloban, Leyte (the Philippines): a degraded Imperata grassland catchment and a catchment that was reforested 23 years prior to our study. Precipitation, stream stage, and electrical conductivity were measured continuously from June to November 2013. Samples were taken from streamflow, precipitation, groundwater, and soil water for geochemical and stable isotope analyses. Streamflow and electrical conductivity changed rapidly during almost every event in the grassland catchment, but in the reforested catchment, these responses were much smaller and only occurred during large events. Streamflow was a mixture of groundwater and precipitation for both catchments, but the maximum event water contributions to streamflow were much larger for the degraded grassland than for the reforested catchment. The differences in the event water contributions and timing of the streamflow responses were observed across all event sizes, including a large tropical storm. Together with the low saturated hydraulic conductivity in the degraded catchment, these results suggest that overland flow occurred more frequently and was much more widespread in the degraded grassland than in the reforested catchment. We, therefore, conclude that reforestation of a degraded grassland can change the dominant flow pathways and restore the hydrological functioning if the forest soil is allowed to develop over a sufficiently long period.

To examine claims that reforesting degraded Imperata grassland in Leyte (Philippines) made streamflow perennial again, we studied the hydrological behaviour of a 23‐year‐old mixed‐species “reforest” between June 2013 and May 2014. Typhoon Haiyan, one of the strongest events ever, caused major damage to the site in November 2013. Average daily apparent water use (ET) was 5.0 mm day−1 pretyphoon and 3.2 mm day−1 after disturbance. Corresponding ratios of period total quickflow Qq to precipitation were 16% and 44%. Quickflow volume and peak discharge increased rapidly once a threshold value of ~250 mm for soil water storage in the top 60 cm was exceeded. Before disturbance, quickflow consisted predominantly of lateral subsurface flow due to high soil hydraulic conductivities down to 60 cm. After disturbance, shallow groundwater rose regularly to within 10 cm of the surface on foot slopes, and saturation overland flow was observed during several large storms. Comparing estimated annual ET and Qq for undisturbed conditions for the reforest and a nearby degraded Imperata grassland microcatchment suggested that the extra infiltration following reforestation (~240 mm year−1) exceeded the extra ET by the reforest (100–185 mm year−1), implying a net positive trade‐off (55–140 mm year−1) and tentatively confirming local claims of improved dry‐season flow.