Abstract 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.

Resumo: A semeadura direta é uma tecnologia que reduz os custos de projetos de restauração florestal e favorece espécies de difícil estabelecimento por mudas. O tratamento osmótico de sementes para acelerar, uniformizar e induzir tolerância a estresses ambientais durante a germinação pode favorecer o estabelecimento de plântulas em campo, por meio da semeadura direta e contribuir para a maior eficiência dessa técnica. Com o objetivo de favorecer a germinação de sementes e o estabelecimento de plântulas em condições de semeadura direta em campo, sementes de Tabebuia roseoalba osmocondiocionadas em solução de polietilenoglicol (PEG) e sementes não condicionadas foram tratadas com soluções isoladas e/ou combinadas de reguladores de crescimento vegetal (PGR) e de enraizantes (RTG). Essas sementes foram submetidas ao teste de germinação e avaliadas quanto à porcentagem de germinação, índice de velocidade de germinação e plântulas normais e ao teste de emergência de plântula, por meio de semeadura direta em campo. O RTG teve um efeito tóxico nas sementes de T. roseoalba. O osmocondicionamento induziu tolerância ao estresse por RTG durante a germinação e o estabelecimento de plântulas. O tratamento com PGR favorece a emergência de plântulas em condições de campo e alivia o efeito da toxicidade causada pelo RTG. Esses tratamentos têm grande potencial de uso na semeadura direta de sementes de T. roseoalba.

Abstract: Direct seeding is a technology that reduces the costs of forest restoration projects and favors species which are difficult to establish for seedlings. The seeds osmotic treatment to accelerate and standardize germination and induce tolerance to environmental stresses may favor seedling establishment in field through direct sowing and contribute to the greater efficiency of this technique. With the purpose of favor seed germination and seedling establishment under direct seeding conditions in the field, Tabebuia roseoalba osmoprimed seeds in polyethylene glycol (PEG) solution and unconditioned seeds were treated with isolated and/or combined solutions of plant growth regulators (PGR) and rooting (RTG). These seeds were submitted to germination test and evaluated for percentage germination rate, germination speed index and normal seedlings, and to seedling emergence test by direct field seeding. RTG had a toxic effect on T. roseoalba seeds. Osmoconditioning induced stress tolerance by RTG during germination and on seedling establishment. PGR treatment favors seedling emergence in field conditions and alleviates the toxicity effect caused by RTG. These treatments have great potential for use in direct sowing of T. roseoalba seeds.

ABSTRACT Agroforestry systems and restoration models were compared with native forests by examining the restoration of ecological processes that generate stability, resilience and reliability. The stability assessment was obtained using indicators of diversity, structure and functionality. Indicators of soil protection and nutrient cycling were also used to estimate the resilience. The reliability was assessed by management and protection indicators, anthropic impact and canopy (percentage of light). Agroforestry systems did not promote the restoration of ecological functions due mainly to structural factors than management. The production of biomass and carbon storage were higher in the agroforestry system considering the association of trees with short cycle crops (3.2 t ha-1 yr-1; 39.81 t C ha-1) than trees with green manure system (2.4 ha-1 yr-1; 34.09 t C ha-1). After 36 months, the restoration methods and agroforestry systems did not provide resilience and stability for the riparian forests protection.

O objetivo do estudo foi analisar o nível de degradação de fragmentos florestais a partir do uso da chuva de sementes como indicador ambiental. Fragmentos (n= 5) de Floresta Estacional Semidecidual na região de Sorocaba - SP foram estudados de agosto a outubro de 2007 e janeiro a dezembro de 2008, utilizando-se coletores instalados em 11 parcelas (10 x 10 m). Do material coletado foram separadas as frações de sementes e frutos para identificação e classificação por síndrome de dispersão e hábito. Os resultados demonstraram que, embora os fragmentos F4 e F5 apresentem os maiores índices de riqueza, diversidade e equitabilidade, há a dominância de espécies anemocóricas e herbáceas. Os fragmentos F1, F2 e F4 foram os com maior aporte de sementes, respectivamente com 36,8%, 26,8% e 17,8% e os fragmentos F3 e F5, apenas 12,6% e 5,9%. O aporte de propágulos foi sazonal sendo maior na transição da estação seca para a úmida, o que resulta em 63% do total de propágulos aportados. A síndrome com maior representatividade foi a anemocoria (86%), comum em áreas abertas e degradadas. Os resultados obtidos indicam a viabilidade da aplicação do estudo quantitativo da chuva de sementes para o monitoramento da restauração de fragmentos, tendo sido eficiente em detectar diferenças ambientais entre os fragmentos.

The aim of this study was to analyze the degradation state of forest fragments applying seed rain as an indicator. Fragments (n = 5) in semideciduous forest, in Sorocaba, SP state, were studied from August to October, in 2007, and from January to December, in 2008, and seed traps were established in 11 plots (10 x 10 m). The material was separated and seeds and fruits were identified and classified based on dispersion syndrome and habit. Although fragments F4 and F5 showed high richness, diversity and equitability, there were dominance of herbaceous and anemochoric species. The highest proportion of seed rain was observed in F1, F2 and F4, with 36.8%, 26.8% and 17.8%, and F3 and F5, showed only 12.6% and 5.9%. The seed rain was seasonal and higher in the transition from dry to wet season, with 63% of total seed rain. The anemochory was the most representative syndrome (86%), that is more observed in open and degraded areas. The results indicated viability of the quantitative analysis of seed rain for monitoring the fragment restoration, being effective to detect environmental differences among fragments.

Os sistemas agroflorestais implantados consistiram da combinação de espécies leguminosas e não leguminosas em plantio "solteiro" (uma planta/cova) e "casado" (duas plantas/cova). Aos quatro anos após o plantio, foram realizadas medições de circunferência na altura do peito (CAP), altura comercial (Hc) e altura total (Ht). Os resultados indicaram a eficiência do plantio "casado" nos sistemas agroflorestais, independente do uso de espécies leguminosas ou não leguminosas, indicando seu potencial de produção silvicultural para a recuperação de áreas degradadas.

The objective of this study was to evaluate the growth of forest species in different agroforestry systems applied to restoration of degraded areas in Paraty-RJ. The agroforestry systems were established with leguminous and non-leguminous species in "single" (one plant/hole) and "married" (two plants/hole) planting. To do so, circumference at breast height, commercial height and total height of the individuals were measured after four years of the planting. The results showed the efficiency of the "married" planting in the agroforestry systems, despite of using leguminous or non-leguminous species, indicating the silvicultural potential for restoration of degraded areas.