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São Francisco de Assis, Brazil

Durigan G.,Forestry Institute of Sao Paulo State | Suganuma M.S.,Forestry Institute of Sao Paulo State | Suganuma M.S.,University of Sao Paulo
Restoration Ecology

The absence of species composition among the indicators of restoration success, recommended for the Brazilian Atlantic Forest by Suganuma and Durigan, was criticized by Reid. In his critic, Reid argues that species composition can be (1) predictable from site history and restoration technique and (2) a surrogate for poor ecosystem functioning and lack of resilience. We disagree on the deterministic view behind the first argument, and the latter is still controversial. Even though, we recommended richness as a good indicator of ecosystem functioning instead of composition-which depends on the exhaustive labor of botanical identification. © 2015 Society for Ecological Restoration. Source

Suganuma M.S.,Forestry Institute of Sao Paulo State | Suganuma M.S.,University of Sao Paulo | Durigan G.,Forestry Institute of Sao Paulo State
Restoration Ecology

Forest restoration by planting trees often accelerates succession, but the trajectories toward reference ecosystems have rarely been evaluated. Using a chronosequence (4-53 years) of 26 riparian forest undergoing restoration in the Brazilian Atlantic Forest, we modeled how the variables representing forest structure, tree species richness and composition, and the proportion of plant functional guilds change through time. We also estimated the time required for these variables to reach different types of reference ecosystems: old-growth forest (OGF), degraded forest, and secondary forest. Among the attributes which follow a predictable trajectory over time are: the basal area, canopy cover, density and tree species richness, as well as proportions of shade tolerant and slow growing species or individuals. Most of the variation in density of pteridophythes, lianas, shrubs and phorophythes, proportion of animal-dispersed individuals, rarefied richness and floristic similarity with reference ecosystems remain unexplained. Estimated time to reach the reference ecosystems is, in general, shorter for structural attributes than for species composition or proportion of functional guilds. The length of this time varies among the three types of reference ecosystems for most attributes. For instance, tree species richness and proportion of shade tolerant or slow growing individuals become similar to secondary forests in about 40 years, but is estimated to take 70 years or more to reach the OGF. Of all the variables considered, canopy cover, basal area, density, and richness of the understory-by their ecological relevance and predictability-are recommended as ecological indicators for monitoring tropical forest restoration success. © 2014 Society for Ecological Restoration. Source

Abreu R.C.R.D.,University of Sao Paulo | Santos F.F.D.M.,University of Brasilia | Durigan G.,Forestry Institute of Sao Paulo State
Acta Oecologica

The recognition of a species as invasive is generally accepted when it comes from another continent or even from another country, but requires strong evidences of negative impacts to support control actions when the invasive species comes from another region in the same country. Schyzolobium parahyba - the 'guapuruvu', is a Brazilian tree native from the evergreen type of the Atlantic Forest, which has been recorded as invader in a number of remnants of the Seasonally Semideciduous Forest - SSF. We hypothesized that this giant and fast growing invasive tree changes the structure and composition of the understory, thus impairing the forest dynamics. We assessed the invasive population in the whole fragment, and, within the portion invaded, we sampled the regenerating plant community 1) under the largest alien trees, 2) under a native species with similar ecology (Peltophorum dubium), and 3) randomly in the forest. Density, basal area and richness under S.parahyba were remarkably lower than under the equivalent native species or in the understory as a whole. Floristic composition of the plant community was also distinct under S.parahyba, possibly due to increased competition for soil water. Even though the alien species has occupied, as yet, a small proportion of the forest fragment, it dominates the overstory and threatens the regeneration processes under its canopy. In view of our findings, we recommend extirpation of the species from SSF, as well as avoiding cultivation of the species away from its native range. © 2013 Elsevier Masson SAS. Source

Durigan G.,Forestry Institute of Sao Paulo State | Ratter J.A.,Royal Botanic Garden Edinburgh
Journal of Applied Ecology

The Cerrado is a fire-dependent savanna requiring a clear and urgent fire management policy. The extensive misuse of fire for deforestation or pasture management in Brazil has created an overall perception that its use is always deleterious. This view, reinforced by threats of global warming and climatic change, has lead to current policies of fire suppression. Cerrado ecosystems depend on the historical fire regime to maintain their structure, biodiversity and functioning. The suppression of fire has transformed savanna vegetation into forests, causing biodiversity losses and drastic changes in ecological processes. Policy implications. The National Fire Policy required by law must be urgently implemented in Brazil, including use of fire for Cerrado conservation in public and private lands on the basis of existing knowledge of indigenous people and scientists. Objective regulations on prescribed burning, land manager training, incentives for fire research and experimentation and a broad campaign to disseminate the benefits of fire for Cerrado conservation should be the cornerstones of the policy. If implemented, the policy can give the biodiversity of the Cerrado a future that has previously been severely threatened by fire suppression. © 2016 British Ecological Society. Source

Podadera D.S.,Sao Paulo State University | Engel V.L.,Sao Paulo State University | Parrotta J.A.,U.S. Department of Agriculture | Machado D.L.,Sao Paulo State University | And 2 more authors.
Environmental Management

Exotic species are used to trigger facilitation in restoration plantings, but this positive effect may not be permanent and these species may have negative effects later on. Since such species can provide a marketable product (firewood), their harvest may represent an advantageous strategy to achieve both ecological and economic benefits. In this study, we looked at the effect of removal of a non-native tree species (Mimosa caesalpiniifolia) on the understory of a semideciduous forest undergoing restoration. We assessed two 14-year-old plantation systems (modified “taungya” agroforestry system; and mixed plantation using commercial timber and firewood tree species) established at two sites with contrasting soil properties in São Paulo state, Brazil. The experimental design included randomized blocks with split plots. The natural regeneration of woody species (height ≥0.2 m) was compared between managed (all M. caesalpiniifolia trees removed) and unmanaged plots during the first year after the intervention. The removal of M. caesalpiniifolia increased species diversity but decreased stand basal area. Nevertheless, the basal area loss was recovered after 1 year. The management treatment affected tree species regeneration differently between species groups. The results of this study suggest that removal of M. caesalpiniifolia benefited the understory and possibly accelerated the succession process. Further monitoring studies are needed to evaluate the longer term effects on stand structure and composition. The lack of negative effects of tree removal on the natural regeneration indicates that such interventions can be recommended, especially considering the expectations of economic revenues from tree harvesting in restoration plantings. © 2015 Springer Science+Business Media New York Source

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