Tree plantation is the most used technique for ecological restoration, although passive restoration requires a lower investment of resources. This research aimed to compare the composition and structure of the community of regenerant plants in areas under restoration through Assisted Natural Regeneration and mixed native Tree Planting, in the same area. We randomly placed 12 plots of 100 m² each and sampled all the regenerating individuals found within them. We compared both restoration methods regarding growth pattern, dispersal syndromes, and successional groups. In both methodologies, trees and shrubs were the most abundant growth forms. The pioneer successional class was the most abundant in number of individuals for both treatments. We concluded that the two restoration methods allowed the regeneration of native species. We propose that Assisted Natural Regeneration is a viable restoration strategy, capable of boosting the initial processes of the community, especially in a matrix surrounded by remaining forests.

Nas comunidades vegetais, as plantas podem interagir de maneira positiva, negativa ou neutra. Essa á uma característica muito importante para garantir a sobrevivência, além de fornecer informações para construção de conhecimento e produtos a serem utilizados no controle específico de algumas plantas daninhas. O objetivo do trabalho foi realizar revisão bibliográfica sobre os efeitos da alelopatia em comunidades vegetais, podendo ser observado tanto nas competições intraespecífica quanto na interespecífica. Com base nos resultados da literatura é provável que os compostos alelopáticos possam alterar componentes do ecossistema que, por sua vez, conduzem processos e interações, as quais modificam a composição e dinâmica das comunidades vegetais. No entanto, uma grande lacuna na pesquisa da alelopatia recai sobre a inexistência de metodologias a serem aplicadas em campo que demonstrem o papel desses compostos no desenvolvimento interespecífico e ao longo da comunidade. Desse modo, faz-se necessário que os estudos levem em consideração quais as fontes de variação entre as espécies, os tipos de impactos causados nas espécies associadas e, principalmente, os seus efeitos em nível de comunidade.

In Brazil, most degraded areas are occupied by exotic and invasive species, which require alternatives for their management. We evaluated the allelopathic effects of Waltheria indica in the laboratory from aqueous extracts of leaves and roots on the germination of the species Lactuca sativa L. (lettuce), Urochloa brizantha (Hochst. ex A.Rich.) RDWebster (brachiaria) and Handroanthus chrysotrichus (Mart. ex DC.) Mattos (yellow Ipe). We collected adult one-year-old Waltheria indica shrubs in ecological restoration areas by direct seeding. We used two treatments with aqueous extracts of leaves and roots and a control without extract, with ten repetitions of 10 seeds per treatment, totaling 600 seeds per test species. Germination and use of tetrazolium assays to evaluate the potential respiratory activity of the roots were used. The aqueous extract of W.indica leaves affected the number of germinated seeds of all test species, while the aqueous extract of roots affected only L. sativa and H. chrysotrichus. There were no significant differences between treatments (leaf and root extracts) in species germination. The aqueous extracts of Waltheria indica leaves and roots affected germination and cellular respiration of the studied species, mainly in Lactuca sativa. The identification of W. indica allelopathic compounds may be an initial step so that in the future new bioherbicides are produced from extracts of this species, or even that its seeds can be sown together with non-sensitive native species, aiming for control of exotic species in ecological restoration projects.

We evaluated band planting (BP) to assess its efficiency in the early restoring of ecological processes using a multi-criteria protocol known as Framework for the Evaluation of Natural Resource Management Systems Incorporating Sustainability Indicators (MESMIS) to obtain the ecological functionality consolidation index (EFCI). We sampled a 4.3 ha-1 plantation, aged 3 years, with BP, 1.5-m space between bands, 2-m space between seedlings, and a 3.5-m band of natural regeneration, ten areas with conventional planting (CP), aged 5 years, in the coverage and diversity models, and ten areas restored by natural regeneration (NR), aged 4 years. Sampling was carried out in 36 10 m x 10 m blocks, totaling 144 plots, 15 blocks for BP, 11 blocks for CP, and 10 blocks for NR. Species richness was similar between the areas; however, there was a significant difference between BP and the other areas (CP and NR) by the Dunn’s test (p < 0.05). The NR area had the highest diversity (H' = 3.03; J' = 0.76), followed by BP (H' = 2.56; J' = 0.62), and CP (H' = 2.0; J' = 0.48), whereas the BP area (4.348 ind.ha-1) had the highest density. The BP had the highest EFCI for diversity (0.100), control, and management (0.067) compared to NR, for diversity (0.022), and similar to CP in soil protection and nutrient cycling (0.047). BP was efficient in recovering early ecological processes under conditions similar to fragments in the initial stage of succession.

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Vegetative propagation is an alternative for the production of seedlings of native tree species such as Schinus terebinthifolia that presents a high predation rate on its seeds. In order to develop vegetative propagation technology, different concentrations of indolebutyric acid (IBA) were tested in the rooting of apical and intermediate minicuttings of Schinus terebinthifolia. The 2x4 factorial experimental design involved two types of minicuttings (apical and intermediate) and four dosages of the hormone IBA (0, 1000, 2000, and 4000 mg. L-1). The percentages of survival and rooting were evaluated. The intermediate minicuttings (37% and 35%) showed significantly greater survival than the apical cuttings (22% and 9%) respectively at 30 and 60 days, regardless of the IBA concentration. Among the rooting averages at 60 days obtained in the different concentrations of IBA, the treatment of 4000 mg. L-1 generated the highest results (9% for apical and 35% for intermediate). The vegetative propagation by minicuttings of Schinus terebinthifolia demonstrated the viability of intermediate minicuttings with high rooting associated with the highest concentration of IBA.

O conhecimento sobre alelopatia pode auxiliar no sistema de cultivo e feitos sobre interações positiva ou negativa entre as plantas. Sendo assim de grande importância o seu conhecimento para auxiliar nas estratégias ecológicas e de manejo da seringueira (Hevea brasiliensis (Willd. ex A.Juss.) Müll.Arg.), espécie de destaque econômico no setor de látex mundial. O objetivo do trabalho foi testar o efeito alelopático da seringueira (H. brasiliensis) na germinação da espécie bioindicadora Alface (Lactuca sativa L.) visando a detecção de possíveis efeitos alelopáticos. Para isso foi utilizado extrato aquoso de folhas adultas de H. brasiliensis na concentração de 200g/L. Foi utilizado um tratamento com extrato aquoso de folhas e um controle sem extrato, com dez repetições de 10 sementes por tratamento. Foi empregado ensaio de germinação para avaliação de porcentagem de germinação (G%), comprimento da radícula e atividade da respiração potencial radicular das plântulas com uso do tetrazólio. Os dados obtidos foram submetidos ao teste de Mann-Whitney (p<0,05). O extrato aquoso de H. brasiliensis afetou o número de sementes germinadas e a respiração celular. No comprimento da raiz não houve diferença significativa. A identificação de compostos alelopáticos do bioensaio fornece dados preliminares para compreensão do comportamento da H. brasiliensis, como também na tomada de decisões estratégicas sobre a interação e dinâmica das comunidades vegetais.

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