Natural forest recovery is an effective ecological alternative to tree planting in tropical forests under certain conditions.

No abstract

Plantations of native-tree species are often recommended for ecological restoration, but the understanding of how these techniques catalyze natural ecological processes is limited. We investigated natural regeneration in five plantations of native trees in the Poço das Antas Biological Reserve (PABR) in the state of Rio de Janeiro, Brazil. The plantations were 9-11 years old, and contained 8-14 native-tree species with different compositions and relative density of species. We analyzed floristic composition, structure (density and basal area) of overstory and understory strata, as well as other ecological attributes (dispersal syndromes, fruit or seed size, and the availability of fruit for frugivores). Zoochorous species comprised 77% of the community, with a prevalence of the two smallest size classes of propagules (<0.6 and 0.6-1.6 cm) in natural regeneration. The density of zoochorous plants in the understory was positively correlated with their density in the overstory, indicating their influence on natural regeneration (r 2 = 0.36; p < 0.0002). Fruit availability for frugivores (density and richness of plants fruiting during the year) was also positively correlated with the density of stems in the understory. Therefore, attributes such as dispersal syndrome and fruiting season should be considered in selecting species to be planted. The differences in natural regeneration observed in each of the native-tree plantations indicated that the performance of plantations as a restoration strategy may differ, depending on initial species composition, planting density, and site conditions.

No abstract

Consideration of soil quality indicators is fundamental for understanding and managing ecosystems. Despite the evidence regarding the importance of soil for provision of local and global ecosystem services, such as water regulation and carbon sequestration, soil remains an under-investigated and undermined aspect of the environment. Here we evaluate to what extent soil indicators are taken into account in restoration. We focused on the Brazilian Atlantic Forest, a highly fragmented biome and a global biodiversity hotspot. We conducted a systematic literature review and we showed that the majority (59%) of the studies on restoration did not consider any soil indicator. Studies that demonstrated the importance of soil indicators most commonly reported soil pH (71%, n = 44), followed by potassium content (66%, n = 41) and phosphorus (64.5%, n = 40), while the least reported indicator was water retention (6.5%, n = 4). Only 40% of the retrieved studies included information about reference sites or project baseline information. We complement our literature review with a case study on restoration in two areas of the Atlantic Forest. We found a relation between soil indicators such as soil organic matter, nitrogen, sodium and sand content, and aboveground indicators, confirming a necessity to include soil screening in restoration. Moreover, we found that prior to restoration none of these soil indicators were analyzed. This study highlights the gap that exists in soil data in restoration in studies on the Brazilian Atlantic Forest. We urge scientists and practitioners to include basic soil analysis to maximize the successful outcomes of restoration.