Abstract The use of direct seeding in projects for the recovery of degraded areas has stood out in some regions of the country because of its effectiveness, lower operating costs, and ease of implementation. Thus, the present study aimed to evaluate the potential of direct seeding the haul in ecological restoration of a deactivated pasture dominated by Urochloa brizantha, here characterized by an invasive weed plant. The experiment consisted of eight treatments resulting from different combinations of seeds (tree and herbaceous cover crops), the use of treatments to break the dormancy of tree species seeds (with and without), and the use of different types of substrates (clay and sawdust). The tested treatments did not affect seedling emergence, survival, or initial growth. The most established species in the study area were Piptadenia gonoacantha, Mabea fistulifera, Dalbergia nigra, and Senegalia polyphylla, which could potentially compose the list of species to be used in forest restoration projects through the use of direct sowing techniques. Plant survival at the end of the evaluation period every three months until the 14 months of experiment implementation corresponded to a density equivalent to 4300 plants per hectare, this result compared to other techniques, shows muvuca as a seeding technique viable direct for the area under study. However, further studies using higher seed densities of cover species are necessary to control the invasive grass Urochloa brizantha effectively.

Resumo O uso da muvuca de sementes em projetos de recuperação de áreas degradadas vem se destacando em algumas regiões do país devido sua eficácia, menor custo de operação e facilidade na implantação. Neste sentido, o presente estudo teve como objetivo avaliar o potencial da semeadura direta por meio do uso da muvuca de sementes na restauração ecológica de uma pastagem desativada e dominada por Urochloa brizantha, aqui caracterizada como planta invasora infestante. O experimento consistiu em oito tratamentos resultantes de diferentes combinações de sementes (espécies arbóreas e herbáceas de cobertura), uso de tratamentos para quebra de dormência das sementes de espécies arbóreas (com e sem) e tipos de substratos (argila e serragem). Os tratamentos testados não apresentaram efeito na emergência, sobrevivência e crescimento inicial das plântulas. As espécies com maior estabelecimento na área em estudo foram Piptadenia gonoacantha, Mabea fistulifera, Dalbergia nigra e Senegalia polyphylla, sendo estas, potenciais para comporem a lista de espécies a serem utilizadas em projetos de restauração florestal por meio do uso da técnica de muvuca. A sobrevivência das plantas ao final do período de avaliação a cada três meses até os 14 meses de implantação do experimento, correspondeu a uma densidade equivalente a 4300 plantas por hectare, este resultado comparado ao de outras técnicas evidencia a muvuca como uma técnica de semeadura direta viável para a área em estudo. Todavia, faz-se necessário novos estudos utilizando maiores densidades de sementes de espécies de cobertura a fim de se obter um controle efetivo da gramínea invasora Urochloa brizantha.

Abstract The aim of this study was to identify tumor parenchyma cells exhibiting immunohistochemical profile of stem cells by evaluating the immunoreactivity of OCT4 and CD44 in a number of cases of salivary gland neoplasms. The sample consisted of 20 pleomorphic adenomas, 20 mucoepidermoid carcinomas, and 20 adenoid cystic carcinomas located in major and minor salivary glands. The expression of OCT4 and CD44 was evaluated by the percentage of positive cells and the intensity of expression. All studied cases showed positive expression of OCT4 and CD44 and higher values than the control groups. For OCT4, luminal and non-luminal cells were immunostained in the case of pleomorphic adenomas and adenoid cystic carcinomas. Moreover, the immunoreactivity of CD44 was particularly evident in the non-luminal cells of these lesions. In mucoepidermoid carcinomas, there was immunoreactivity for both markers in squamous and intermediate cells and absence of staining in mucous cells. For both markers, a significantly higher immunostaining was verified in neoplasms located in the major salivary glands compared with lesions in minor salivary glands (p<0.001). In the total sample and in minor salivary glands, malignant neoplasms exhibited higher immunoreactivity for OCT4 than pleomorphic adenoma. A significant moderate positive correlation (r = 0.444 and p ≤ 0.001) was found between OCT4 and CD44 immunoexpression in the total sample. The high expression of OCT4 and CD44 may indicate that these proteins play an important role in identifying tumor stem cells.

Resumo A atividade de mineração, importante para a promoção do crescimento econômico e do bem-estar social, tem sido responsável pela modificação de grandes extensões de paisagens do território nacional. Dessa forma, objetivou-se no presente estudo correlacionar às espécies vegetais em três diferentes sítios de uma área de mineração de ouro abandonada há mais de cem anos. A área em estudo foi estratificada em três sítios, sendo que em cada sítio foram alocadas dez parcelas contiguas de 10x10 m cada, onde foram amostrados e identificados todos os indivíduos arbustivo-arbóreos com (DAS30≥ 3 cm). Amostras compostas do substrato foram coletadas à profundidade de 0 cm a 20 cm, em cada uma das trinta parcelas e analisados os teores de areia, silte, argila, matéria orgânica, pH, P, K+, Ca2+, Mg2+, S, Al3+, (H +Al), (V%), (SB), CTCa pH 7, (T), CTC efetiva (t) e (m%). Foi analisada a influência de variáveis ambientais sobre a densidade das espécies amostradas, utilizando análise de correspondência canônica, verificando a correlação significativa entre elas (P>0,01) pelo teste de Monte-Carlo. Foram encontrados 909 indivíduos, pertencentes a 30 famílias botânicas, 64 gêneros e 86 espécies. As variáveis mais fortemente relacionadas com a vegetação foram silte, pH e V. As espécies Trembleya parviflora, Myrsine guianensi, Trembleya laniflora, Baccharis brachylaenoides, Tibouchina candoleana, Tibouchina mutabilis e Pseudobrickellia angustissima ocorreram de forma mais abundantes em solos com altos valores de pH, saturação por bases e altas proporções de areia, podendo ser consideradas indicadoras desses habitats.

Abstract The mining activity, important for promoting economic growth and social welfare, has been responsible for the modification of large tracts of landscape nationwide. Thus, this work aimed to relate the colonizing species of the area of gold mining with the substrate, in Diamantina, Minas Gerais state. An area under study was stratified into three locations, with ten contiguous plots measuring 10 x 10 m each in each location, where all individuals with shrubs with (DAS30≥ 3 cm) were sampled and recorded. Soil composite samples were collected at a depth of 0 cm to 20 cm in each of the thirty plots and analyzed the levels of sand, silt, clay, organic matter, pH, P, K, Ca, Mg, S, Al, (H + Al), (V%) (SB), CTC at pH 7, (T), CTC (t) (m%). The influence of environmental variables on the density of the sampled species was analyzed by using the canonical correspondence analysis, verifying the significant correlation between them (P> 0.01) by the Monte-Carlo test. Nine-hundred and nine (909) individuals were found, belonging to 30 botanical families, 64 genera and 86 species. The variables most strongly related to vegetation were silt, pH and V. The species Trembleya parviflora, Myrcine guianensi, Trembleya laniflora, Baccharis brachylaenoides, Tibouchina candoleana, Tibouchina mutabilis e Pseudobrickellia angustissima,occurred were more abundant in soils with high pH, base saturation and high proportions of sand may eventually be shown as potential in the recuperation of mined areas with similar conditions to the area.

Resumo Este estudo teve como objetivo analisar a dinâmica da estrutura de espécies arbóreas e relacionar as mudanças com as condições edáficas em fitofisionomias de cerrado stricto sensu (de 2010 a 2015), cerradão (de 2010 a 2015) e floresta estacional semidecidual (de 2011 a 2015) em Curvelo, Minas Gerais. O inventário florestal considerou amostragens do tipo sistemática em 15 unidades amostrais de 20 × 50 metros no cerrado stricto sensu (CSS), 10 unidades amostrais 20 × 50m no cerradão (CD), CAS ≥ 15,7cm) e 25 unidades amostrais de 10 × 40m na floresta estacional semidecidual (FES - CAP ≥ 15,7 cm). Amostras de solo foram coletadas em todas as unidades amostrais para caracterização química e granulométrica. Nas três fitofisionomias, o número de indivíduos ingressantes foi inferior ao de egressos. No CSS, a área basal no inventário final foi superior à área basal inicial (23,675 - 25,845m2/ha), devido ao incremento expressivo dos sobreviventes. Ocorreram reduções na área basal no CD (19,322 - 17,008 m2/ha) e na FES (28,183 - 28,148 m2/ha), decorrente da alta taxa de mortalidade. Nas três fitofisionomias, a mortalidade foi maior nas primeiras classes diamétricas. De forma lenta, o CSS e CD estão se recuperando pós-distúrbio (fogo), estão surgindo novos indivíduos (recrutas) e crescimento diamétrico dos sobreviventes. Durante o intervalo de 5 anos, não foi possível identificar a recuperação do número de indivíduos, enquanto a FES sem distúrbio do fogo, a perda de indivíduos pela mortalidade e a inclusão de novos indivíduos pelo recrutamento foram mais equilibradas.

Abstract This study aimed to analyze the structural dynamics of tree species and to relate changes with edaphic conditions in the phytophysiognomies of cerrado stricto sensu (from 2010 to 2015), cerradão (from 2010 to 2015) and seasonal semideciduous forest (from 2011 to 2015) in Curvelo, state of Minas Gerais, Brazil. Forest inventories involved systematic sampling in 15 sample units (20 × 50m) in cerrado strict sensu (CSS), 10 sample units (20 × 50m) in cerradão (CD; CAS ≥ 15.7 cm) and 25 sample units (10 × 40m) in semideciduous seasonal forest (SSF; CAP ≥ 15.7 cm). Soil samples were collected in all sample units for the chemical and granulometric characterization. The number of individuals entering was lower than the total recruitment in all phytophysiognomies. Basal area in the final inventory of CSS was higher than initial basal area (23.675 - 25.845m2/ha), due to a significant increase in the surviving individuals. There were reductions in the basal area for DC (19.322 - 17.008 m2/ha) and SSF (28.183 - 28.148 m2/ha), due to high mortality rates. The mortality was higher for the first diametric classes in all three phytophysiognomies. Individual recruitment and diametric growth of survivors during post fire disturbance recovery was slow for CSS and CD. The number of individuals recovering during a 5-year interval could not be determined, however, without fire disturbance, the loss of individuals due to mortality and the recruitment of new individuals in FES were more balanced.

Resumo Objetivou-se descrever e caracterizar a morfologia de frutos, sementes, plântulas, e germinação de Richeria grandis. Frutos maduros foram coletados de árvores-matrizes localizadas em matas de galeria e, posteriormente, foram realizadas descrições morfológicas. Procedeu-se a mensuração biométrica dos frutos e sementes. Ainda, após beneficiamento, foram separados de forma aleatória, 650 sementes, em que 20% foram utilizadas para germinação e teste de umidade no mesmo dia da coleta e as outras, armazenadas durante 5, 10, 15 e 20 dias. O teste de germinação foi realizado em gerbox, feito em câmeras do tipo B.O.D. com um fotoperíodo de 12 h e temperatura de 25 ºC ± 1 ºC. Realizou-se observações periódicas para o acompanhamento do desenvolvimento das plântulas até que as primeiras sementes germinadas atingissem o estádio de plântula completa. O fruto da R. grandis é simples, seco, do tipo cápsula septífraga, deiscentes e esquizocarpos, com comprimento médio de 16,24 mm e largura média de 8,57 mm. A semente é elipsoide com presença de sarcotesta, com comprimento médio de 7,40 mm e largura média de 4,57 mm. A R. grandis apresenta sementes recalcitrantes. A emergência é do tipo Fanero-epígeo-foliáceo. A radícula rompe o tegumento no segundo dia após a semeadura, o coleto é evidenciado ao 10º dia, separando a raiz primária do hipocótilo. A partir do 16º dia, os cotilédones expandem-se da testa, posicionados em um ângulo de 90º em relação ao hipocótilo. O protófilo e o epicótilo surgem somente após o 50º dia, caracterizando a plântula completa.

Abstract The objective was to describe and characterize the fruit morphology, seeds, seedlings and germination of Richeria grandis. Mature fruits were collected from matrix trees located in gallery forests. After, morphological descriptions were performed. Biometric measurement of fruits and seeds were carried out. A total of 650 seeds were randomly separated, with 20% being used for germination and humidity testing on the same day of collection and the others stored for 5, 10, 15 and 20 days. The germination test was performed in a gerbox, conducted in a laboratory chamber of the type B.O.D (biochemical oxygen demand) with a photoperiod of 12h and a temperature of 25 ºC ± 1 ºC. Periodic observations were made to monitor the development of the seedlings until the first germinated seeds reached the full seedling stage. The fruit of R. grandis is a simple, dry, capsule type septifraga, dehiscent and schizocarpic, with average length of 16.24 mm and an average width of 8.57 mm. The seed is an ellipsoid shape, containing a sarcotesta and has an average length of 7.40 mm and an average width of 4.57 mm. R. grandis presents recalcitrant seeds, which emerge in a Phanero-epigene-foliaceous manner. The radicle breaks the integument on the second day after sowing, the collection is evidenced on the 10th day, separating the primary root from the hypocotyl. At day 16, the cotyledons expand from the forehead, positioned at a 90º angle to the hypocotyl. The protophyll and the epicotyl appear only after the 50th day, characterizing the complete seedling.

ABSTRACT The objective of this work was to evaluate the behavior of Vetiveria zizanioides when grown in tailings from quartzite mining. A greenhouse experiment was conducted in a completely randomized experimental design with four replicates. The treatments consisted of five combinations of organic (OF) and mineral fertilization (MF) and an additional treatment of the tailings without OF or MF (control). The combinations were 0%OF/100%MF, 25%OF/75%MF, 50%OF/50%MF, 75%OF/25%MF, and 100%OF/0% MF. The doses of 100% of MF and OF were 0.025 g N, 0.025 g P2O5, 0.020 g K2O, and 5 g of corral manure per kg of quartzite tailings. V. zizanioides responded to MF at the recommended doses of 0.025 g N, 0.025 g P2O5, and 0.020 g K2O per kg of tailings. It is concluded that quartzite tailings form a favorable habitat for V. zizanioides growth, mainly after being altered by MF.

ABSTRACT Pteridium aquilinum is an invasive species that stands out for its aggressiveness, invading pastures, agricultural areas and forests. In order to improve this situation, several techniques have been tested, although not common to tropical climate areas. Thus, the objective of this study was to evaluate the survival of eleven tree species according to their density, planting model, and way of bracken removal, in the restoration of an Atlantic Forest area invaded by the species after a fire. The experiment was installed in a randomized block design, in a 2 × 3 × 2 factorial arrangement (planting × density × bracken removal methods). Bracken cover and survival were evaluated nine months after planting. In conclusion, more densified plantations with fast-growing species, together with bracken removal by harrowing, were more effective in establishing the species in bracken-dominated areas.

RESUMO Conduziu-se um experimento em casa de vegetação com o objetivo de avaliar o comportamento de Solanum lycocarpum sob a influência da adubação mineral e orgânica quando cultivada em rejeito da mineração de quartzito visando subsidiar ações voltadas para a recuperação de áreas de exploração de quartzito. Os tratamentos consistiram de cinco combinações de adubação orgânica (AO) e mineral (AM) e um tratamento adicional do rejeito sem AO e AM (Controle). As combinações foram: 0%AO/100%AM; 25%AO/75%AM; 50%AO/50%AM; 75%AO/25%AM; 100%AO/0% AM. As doses que corresponderam ao tratamento de 100% de AM e AO foram de 150 mg de N, 140 mg de P, 150 mg de K e 5 g de esterco de curral por dm3 de rejeito. A Solanum lycocarpum respondeu à adubação mineral e orgânica com as doses recomendadas de 36,0 mg N, 33,6 mg P e 36,0 mg K e 3,8 g de esterco de curral por dm3 de rejeito da mineração de quartzito. O acúmulo de nutrientes na espécie Solanum lycocarpum nas doses recomendadas foi na seguinte ordem na parte aérea: N> K > Ca > P > S > Mg > Mn > B > Fe > Cu > Zn com adubação mineral e orgânica para o máximo crescimento da espécie.

ABSTRACT In order to evaluate the behavior of Solanum lycocarpum, grown in sterile tailings, from mining of quartzite under the influence of mineral and organic fertilization to support actions for the recovery of exploration areas of quartzite, it was conducted an experiment in a greenhouse in a completely randomized design with four replications The treatments consisted of five combinations of mineral (MF) and organic (OF) fertilizer and an additional treatment of the sterile reject without MF and OF (Witness). The combinations were: 0%OF/100%MF; 25%OF/75%MF; 50%OF/50%MF; 75%OF/25%MF; 100%OF/0% MF. Doses of 100% MF and OF were de 150 mg de N, 140 mg de P, 150 mg de K, e 5 g bovine manure per dm3 of sterile. The Solanum lycocarpum responded to mineral fertilization with the recommended doses of 36 mg N, 33,6 mg P e 36 mg K e 3,8 g bovine manure per dm3 of sterile tailings from mining of quartzite. The accumulation of nutrients in the species Solanum lycocarpum at recommended doses in the following order was on the shoot: N> K > Ca > P > S > Mg >Mn> B > Fe > Cu > Zn with fertilization mineral and organic for maximum growth of the of species.

ABSTRACT Rupestrian complexes of the Serra do Espinhaço are recognized for their high degree of biodiversity and endemism. However, environmental impacts, particularly from mining, have degraded these environments. The purpose of this study was to describe the herbaceous-subshrub communities that occur in quartzitic (QRC) and ferruginous (FRC) rupestrian complexes in different seasons of the year, with regard to floristic similarity and phytosociological structure. Additionally, the study aimed to identify native species with potential use for the restoration of similar degraded areas. Vegetation was sampled from plots located in the municipality of Conceição do Mato Dentro, state of Minas Gerais. Five contiguous strata of 10 × 50 m were demarcated in each environment, in which 12 plots of 2 × 1 m (2 m²) were randomly distributed, for a total of 60 plots (sample units) in each physiognomy. The studied communities exhibited few similarities and lower floristic diversity than other rupestrian complexes. Detrended correspondence analysis distinguished the communities of FRC from those of QRC. The species with the highest value of importance in FRC were Bulbostylis fimbriata and Centrosema brasilianum, while in QRC Echinolaena inflexa had the highest values, thus, making them eligible for restoration programs in similar environments.

ABSTRACT The objective of this study was to evaluate the initial growth of Eremanthus incanus (Less.) Less (candeia) in soil with manganese doses. Additionally, it sought to assess manganese concentration, and accumulation in the organs of the plant as well as quantify the appropriate concentration of this element in the soil. The experiment was installed in a greenhouse and used manganese doses of 0, 50, 150 and 450 mg kg-1 soil. The experimental design used randomized blocks with five replications. Stem diameter and plant height; dry matter of root, shoot and total, and concentration and accumulation of manganese in the leaf, stem and root were evaluated. The manganese concentration in the soil was quantified using the Mehlich-1 and DTPA pH 7.3 extractors. A reduction in growth and high manganese concentrations in all parts of the plant were observed. For Melich-1 extraction the appropriate manganese concentration is 15.90 mg kg-1 and for DTPA it is 3.02 mg kg-1. The use of the candeia for phytoremediation is not recommended due to sensitivity to manganese.

RESUMO Complexos rupestres apresentam uma grande diversidade de padrões fenológicos como resposta à alta biodiversidade deste ecossistema e sua variação ambiental. Espécies dioicas apresentam distinção entre os sexos quanto às exigências nutricionais para crescimento e reprodução, compreendendo fatores determinantes na variação da fenologia reprodutiva e vegetativa, principalmente em ambientes restritivos. O estudo objetivou compreender a fenologia reprodutiva e vegetativa da espécie dioica Baccharis platypoda, associando as estratégias fenológicas ao sistema sexual e às variações sazonais do ambiente. O estudo foi realizado em três áreas de campo rupestre, onde foi observada a fenologia de trinta plantas, entre setembro/2010 e setembro/2011. Foram aplicados o método de intensidade de Fournier, correlação de Spearman e análise circular. As fenofases reprodutivas tiveram início no mês de fevereiro com encerramento entre setembro e outubro, enquanto que as fenofases vegetativas apresentaram variações de intensidade ao longo desse período. As fenofases vegetativas de ambos os sexos apresentaram baixo padrão sazonal, enquanto que as fenofases reprodutivas apresentaram forte sazonalidade. A espécie B. platypoda apresentou pequenas variações nas estratégias fenológicas de indivíduos masculinos e femininos, principalmente na duração das fenofases reprodutivas e no crescimento vegetativo para alocação de recursos. A fenologia reprodutiva da espécie esteve associada a algumas variáveis ambientais, principalmente para as fenofases de frutificação, enquanto que a fenologia vegetativa, de modo geral, esteve mais associada à fenologia reprodutiva das espécies.

ABSTRACT Rupestrian grasslands present great diversity of phenological patterns in response to the high biodiversity of this ecosystem and its environmental variation. Dioecious species show distinction between the genders in relation to the nutritional requirements for growth and reproduction, comprehending determining factors, especially in restrictive environments. The purpose of the study was to comprehend the reproductive and vegetative phenology of the dioecious species Baccharis playtypoda, joining the phenological strategies with the sexual system and the environment seasonal variations. The study was performed in three areas of rupestrian grassland, where the phenology of thirty plants from September/2010 through September/2011 was observed. The Fournier intensity method, Spearman’s correlation and circular analysis were used. The reproductive phenophases began in February and ended between September and October, while the vegetative phenophases presented intensity variation during that period. The vegetative phenophases of both genders has shown low seasonal standard, while the reproductive phenophases has presented strong seasonality. The species B. platypoda has presented little variations in the phenological strategies of male and female individuals, mainly during the reproductive phenophases and in the vegetative growth for the allocation of resources. The species’ reproductive phenology had been associated to some environmental variables, mainly for the fructification phenophases, while the vegetative phenology, in general, had been most associated to the reproductive phenology of the species.

Resumo: O objetivo deste trabalho foi avaliar a influência da espessura, sombreamento e origem do topsoil na restauração ambiental de uma área de pastagem degradada. O experimento foi realizado em delineamento em blocos casualizados, em esquema fatorial (3 x 2 x 2) + 2. Os tratamentos foram compostos pela combinação das origens do topsoil (estágio inicial ou médio de regeneração), espessuras do topsoil (10, 20 ou 30 cm de camada superficial de solo) e ausência ou presença de sombrite de 70%; com duas testemunhas adicionais (T1 e T2). Foi realizada a caracterização físico-química do topsoil, assim como o levantamento florístico e a cobertura do solo. Houve boa correlação entre a densidade do solo e a porosidade total. A cobertura vegetal desenvolvida apresentou um total de 2.932 indivíduos de hábitos herbáceo, arbustivos e subarbustivos, identificadas 33 espécies em 11 famílias e 1 morfoespécie. Já o levantamento florístico do estrato arbóreo registrou 235 indivíduos pertencentes a 21 espécies e 14 famílias e 2 espécies sem identificação. O topsoil de 20 cm de espessura é o que apresenta melhor índice de regeneração natural, onde o sombreamento exerceu uma influência positiva sobre a umidade e a regeneração natural do banco de sementes. O topsoil proveniente de floresta de estágio médio é o mais adequado para restauração de áreas de pastagem degradadas.

Abstract: The objective of this work was to evaluate the influence of topsoil thickness, shading and origin when performing environmental restoration in a degraded pasture area. The experiment was conducted in a randomized block design with a factorial (3 x 2 x 2) + 2 layout. Treatments consisted of combinations of topsoil origins (forest at early or middle regeneration stages), topsoil thicknesses (10, 20, or 30-cm superficial soil layer), and presence or absence of 70% shading; with two additional control treatments. Surveys on topsoil physical-chemical attributes and flora and soil coverage were conducted. Good correlation was observed between bulk density and total porosity. Vegetation comprised a total of 2,932 individuals of herbaceous, shrub and subshrub plants; 33 species in 11 families and 1 morphospecies were identified. A floristic survey of the tree stratum revealed 235 individuals belonging to 21 species and 14 families, as well as 2 unidentified species. The best natural regeneration index is observed in the 20-cm topsoil layer, where shading exerts a positive influence on the humidity and natural regeneration of the seed bank. Topsoil from middle-stage forest is the most suitable for restoration of degraded pasture areas.

RESUMO Objetivou-se avaliar a regeneração natural pós-fogo em uma área de campo sujo. Foram selecionados três ambientes; I e II, com ocorrência de fogo, e III, sem ocorrência. Em cada local foi instalado um transecto com 20 parcelas de 5 × 5 m (25 m2). Foram mensurados o diâmetro ao nível do solo (DNS), altura total e rebrota de todos os indivíduos com altura ≥ 0,10 m e DNS ≤ 5,0 cm. Nos ambientes I e II foram amostrados 436 e 387 indivíduos e 29 e 24 espécies, respectivamente. Já no ambiente III foram amostrados 741 indivíduos e 29 espécies. Houve diferença significativa no número de perfilhos, número de indivíduos e na área basal. Nos ambientes I e II, 72% e 88%, respectivamente, apresentaram indícios de rebrotamento. O incêndio modificou a estrutura da vegetação e a rebrota foi a principal estratégia utilizada pelas espécies nos locais com ocorrência de incêndio.

ABSTRACT This study aimed to evaluate the natural post-fire regeneration in dry grassland. We selected three sites: I and II, with occurrence of fire and III with no occurrence. Each site received one transect with 20 plots of 5 × 5m (25m 2). Diameter at ground level (DNS), total height and regrowth of all individuals with height ≥ 0.10 m and DNS ≤ 5.0 cm were measured. Sites I and II, respectively, had 436 and 387 sampled individuals, and 29 and 24 species. Site III had 741 individuals and 29 species sampled. There was a significant difference in the number of tiller, individuals and basal area. In sites I and II, 72% and 88%, respectively, showed signs of regrowth. The fire changed the structure of vegetation, and regrowth was the main strategy used by species in sites with fire occurrence.

RESUMO: As translocações de populações raras são consideradas como o último recurso para conservação de espécies, cuja destruição do habitat é iminente. O objetivo deste trabalho foi avaliar o efeito de duas classes de altura e três intensidades de redução foliar no crescimento, incremento periódico, sobrevivência e inserção de folhas em mudas de Aspidosperma cylindrocarpon (peroba) obtidas via resgate de plântulas em um remanescente de Floresta Estacional Semidecídua. Foram resgatados 240 indivíduos, os quais foram divididos em duas classes de altura (Classe I-5 a 15cm e Classe II-20 a 35cm), submetidos a três intensidades de redução foliar (0%, 50% e 100%) e em seguida, transportados para casa de sombra com 50% de redução de luminosidade. As medições de altura, diâmetro e emissão de novas folhas foram realizadas em oito tempos (0, 15, 60, 75, 90, 105, 120 e 135 dias), e a sobrevivência aos 135 dias. A taxa média de sobrevivência foi de 82,9%, sendo 77,5% para a classe de 5-15cm e 88,3% para classe de 20-35cm. O maior crescimento das mudas ocorreu para a redução de 0%, para ambas as classes. A inserção de folhas foi maior nas reduções de 100%, observando-se diminuição ao longo do tempo. Portanto, é aconselhável resgatar mudas de peroba nas duas classes de altura, sem necessidade de redução foliar.

ABSTRACT: Translocation of rare populations is regarded as the last resort for the conservation of species whose habitat destruction is imminent. The objective of the present study was to evaluate the effect of two height classes and three leaf reduction intensities on growth and increases in height, stem diameter, survival, and new leaf production in seedlings of Aspidosperma cylindrocarpon (peroba) obtained via rescue seedlings in a remnant of tropical semi deciduous forest. We recovered 240 individuals that were divided into two height classes (Class I-5 to 15cm and Class II-20 to 35cm) and subjected to three leaf reduction intensities (0%, 50%, and 100%), which were then transported to a shade house with 50% light reduction. Measurements of height, stem diameter, and new leaf production were collected 8 times at 0, 15, 60, 75, 90, 105, 120, and 135 days, and survival rate was measured at day 135. The average survival rate was 82.9%; 77.5% for one Class I (5-15cm) and 88.3% for Class II (20-35cm). Higher seedling growth was observed for the 0% leaf reduction treatment in both height classes. The leaves insertion were greater in the 100% cuts, with a decrease observed over time. It is advisable to restore A. cylindrocarpon seedlings in two height classes owing to the high survival rate, leaf appearance, and growth reported in the present study. The no-leaf reduction treatment (0%) is the most viable alternative for the production of A. cylindrocarpon seedlings, via rescue seedlings.

RESUMO A contaminação de ecossistemas por resíduos de defensivos agrícolas, especial atenção deve ser dada para os herbicidas passíveis de lixiviação. O objetivo foi selecionar espécies arbóreas para a rizodegradação de ambientes contaminados por resíduos de 2,4-D e atrazine, e para recomposição de mata ciliar aos campos agrícolas e, consequentemente, diminuir riscos de contaminação de cursos hídricos. Foram avaliados 36 tratamentos compostos pela combinação de 12 espécies florestais: [inga- Inga marginata Willd, guapuruvu - Schizolobium parahyba (Vell), ipê amarelo- Handroanthus serratifolius (A.H.Gentry) S.Grose, carobinha - Jacaranda puberula Chan, cedro- Cedrela fissilis Vell, landin -Calophyllum brasiliense Camb, goiabinha- Psidium myrsinoides Berg, quaresmeira-Tibouchina granulosa Cogn, pau-ferro - Caesalpinia ferrea Mart, sibipiruna - Caesalpinia pluviosa DC, capitão -Terminalia argentea Mart & Zucc e braúna- Schinopsis brasiliensis Enge S.F.Blacke] e três soluções simulando o composto lixiviado (atrazine, 2,4-D e água - controle), com quatro repetições cada. Foram mensuradas a altura da planta, o diâmetro do caule, o número de folhas, a área foliar e o acúmulo de biomassa seca e a nutrição foliar. A maioria das espécies apresentou increaseo em macronutrientes mesmo submetidas à aplicação dos herbicidas, sendo que o inga apresentou maior tolerância em relação as análise de crescimento. Assim, recomenda-se a utilização das espécies mais tolerantes aos herbicidas Atrazine e 2,4-D em experimentos de campo para confirmar os resultados preliminares desta simulação.

ABSTRACT Ecosystems contamination by residues of pesticides requires special attention to the herbicides subject to leaching. The objective was to select tree species to rhizodegradation contaminated by residues of 2,4-D and atrazine and to recompose riparian areas to agricultural fields, then reducing the risk of contamination of water courses. A total of 36 treatments consisted of the combinations of forest species were evaluated [Inga marginata (Inga), Schizolobium parahyba (guapuruvu), Handroanthus serratifolius (ipê amarelo), Jacaranda puberula (carobinha), Cedrela fissilis (cedro), Calophyllum brasiliensis (landin), Psidium mirsinoides (goiabinha), Tibouchina glandulosa (quaresmeira), Caesalpinia férrea (pau-ferro), Caesalpinia pluviosa (sibipiruna), Terminalia argêntea (capitão) and Schinopsis brasiliensis (braúna)] and three solutions simulating leachate compound (atrazine, 2,4-D and water - control), with four replicates each. The characteristics measured were plant height, stem diameter, number of leaves, leaf area and dry biomass, and foliar nutrition. Forest species survived the herbicide application, and most showed an increase in macronutrients even under an herbicide application, and the Inga had the highest tolerance regarding growth analysis. It is recommended to use species that are more tolerant to Atrazine and 2,4-D in field experiments to confirm previous results of this simulation.