Soilseed bankastogrant recovery of the riparian forest

O presente trabalho teve como objetivo conhecer a densidade e composição do banco de sementes do solo em dois ambientes de mata ciliar alterada, no entorno de uma nascente. A nascente estudada pertence à bacia hidrográfica do rio Capivari, no município de Itumirim, MG (21º16’ S e 44º52’ W). Nos dois ambientes estudados, foram coletadas 18 amostras de solo a 5,0 cm profundidade, no final da estação chuvosa (maio de 2003). Calculou-se a densidade de sementes e a curva de germinação do banco pelo método de emergência de plântulas. Também foi feita a determinação da composição florística, com base principalmente na morfologia das plântulas. Após um período de 210 dias de avaliação, obteve-se uma densidade de 2.332 sementes/m2 no Ambiente I e 1.896 sementes/m2 no Ambiente II. No entanto constatou-se que o banco de sementes dos dois ambientes avaliados era composto apenas por espécies ruderais. Tais resultados evidenciam a necessidade de intervenção humana no processo de recomposição da vegetação ciliar no entorno dessa nascente, por meio da regeneração artificial de espécies arbóreas.Palavras-chave: Banco de sementes do solo; nascente e recomposição da vegetação. AbstractSoilseed bankastogrant recovery of the riparian forest. The present work objective knows the density and composition of soil seed bank in ciliary areas altered in spill of two springs. The studied springs belong to Capivari river catchment, Itumirim, MG (21º16'S and 44º52 ' W). The samples of soils were collected in the end of the rainy station (May of 2003). Were 18 soil samples were collected for the two environments to the depth of 5 cm. was calculated the density of seeds and the curve of germination of the soil seed bank, for method of seedling emergency. It was also made the determination of the floristic composition based mainly on the morphology of the seedling. After a period of 210 days of evaluation obtained a density of 2332 seed/m2 was observed in the environment I and 1896 seed/m2, for the environment. However, it was verified that the bank of seeds of the two appraised East was just composed of ruderal species. Such results evidence the need of human intervention in the process of restoration of the ciliary vegetation in spill of this spring, through the artificial regeneration of the arboreal species.Keyword: Seed bank; spring and restoration of the vegetation.The present work objective knows the density and composition of soil seed bank in ciliary areas altered in spill of two springs. The studied springs belong to Capivari river catchment, Itumirim, MG (21º16'S and 44º52 ' W). The samples of soils were collected in the end of the rainy station (May of 2003). Were 18 soil samples were collected for the two environments to the depth of 5 cm. was calculated the density of seeds and the curve of germination of the soil seed bank, for method of seedling emergency. It was also made the determination of the floristic composition based mainly on the morphology of the seedling. After a period of 210 days of evaluation obtained a density of 2332 seed/m2 was observed in the environment I and 1896 seed/m2, for the environment. However, it was verified that the bank of seeds of the two appraised East was just composed of ruderal species. Such results evidence the need of human intervention in the process of restoration of the ciliary vegetation in spill of this spring, through the artificial regeneration of the arboreal species

Restauração ecológica em área de pastagem por semeadura direta

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.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

GROWTH OF Kielmeyera rubriflora INOCULATED WITH ARBUSCULAR MYCHORRIZAL FUNGI ON IRON MINING SUBSTRATES

Mining results in major landscape changes. Restoring areas after exploitation of natural resources can be accomplished through adopting techniques used to optimize the restoration process. Among such techniques, planting seedlings of species adapted to adverse edaphoclimatic conditions and which have interspecific associations with microorganisms stand out. One of these indigenous species which occur in the Southern Espinhaço Mountain Range with potential for use in restoring degraded areas is Kielmeyera rubriflora (Spreng) Mart. Thus, the objective of this study was to evaluate the influence of inoculating arbuscular mycorrhizal fungi on the survival and growth of Kielmeyera rubriflora Cambess. on two substrates from iron mining. The experiment was carried out in a nursery of the UFVJM Plant Species Propagation Center (CIPEF) in a randomized block design and treatments arranged in a 2 x 2 factorial design, using two iron mining substrates and inoculated and uninoculated plants with five repetitions. The seedlings received 25 g of the soil-inoculum mixture of Paraglomus occultum (C. Walker) JB Morton & D. Redecker and Claroideoglomus etunicatum (WN Becker & Gerd) C. Walker & A. Schüßler at the transplantation time to 17 dm3 pots. Stem diameter and leaf number were influenced only by the main effects of substrate and inoculation, while plant height was influenced by the interaction between substrate and inoculation. Inoculation with mycorrhizal fungi in Kielmeyera rubriflora ensures survival, species growth and root development on both iron mining substrates and is a suggested strategy for planting in areas degraded by iron mining

NODULAÇÃO DE LEGUMINOSAS COM POTENCIAL DE USO NA RECUPERAÇÃO DE ÁREAS DEGRADADAS EM CAMPO RUPESTRE QUARTZÍTICO

The objective of this work was to evaluate the composition and structure of leguminous species in vegetal formation of rocky fields in Serra do Espinhaço Meridional, as well as to verify the diversity of nitrogen-fixing bacteria of the nodular species. The floristic survey was carried out in a reserve area belonging to the Anglo American mining company, based in the municipality of Conceição do Mato Dentro - MG. The region is located on the eastern edge of the Serra do Espinhaço Meridional and has a Cwa climate. To carry out the floristic survey, 25 fixed plots (10×10 m) were installed for the shrub-tree compartment and 60 fixed plots (1 × 2 m) for the herb-subshrub compartment. Absolute and relative density, absolute and relative frequency were estimated for both compartments. After the previous floristic survey, 40 root nodules of the species of Calliandra fasciculata and 23 of Moldenhawera emarginata were collected. Afterwards, bacteria were isolated from the nodules from the species C. fasciculata and M. emarginata. The cultural characteristics of the isolates were evaluated and from the data, it was possible to group the isolates through a cultural dendrogram using the Jaccard coefficient, using the MVSP (Multivariate Statistical Package) software. Three leguminous species were recorded in both compartments, totaling 1192 individuals distributed among C. fasciculata (with 1080 ind.), M. emarginata (with 86 ind.) and Periandra mediterranea (with 26 ind.). However, for the species P. mediterranea, no nodulation was observed in the field. The species C. fasciculata was responsible for 92.62% of the total number of individuals. From the morphological characteristics successfully evaluated, of the 23 isolates of C. fasciculata, 6 cultural groups were obtained. This result suggests high morphophysiological diversity of nitrogen-fixing bacteria nodulating the species in question, in a quartzite rock field environment. Due to the importance of this species, its use in recovery projects is recommended, especially in environments similar to the one in this study.Este trabalho teve o objetivo de avaliar a composição e estrutura de espécies leguminosas em formação vegetal de campo rupestre na Serra do Espinhaço Meridional, assim como verificar a diversidade de bactérias fixadoras de nitrogênio das espécies nodulíferas. O levantamento florístico foi realizado em uma área de Reserva Legal da empresa Anglo American no município de Conceição do Mato Dentro, Minas Gerais. A região está inserida na Borda Leste da Serra do Espinhaço Meridional e apresenta clima Cwa. Instalou-se 25 parcelas fixas (10 × 10 m) para a comunidade arbustivo-arbóreo e 60 parcelas fixas (1 × 2 m) para a comunidade herbáceo-subarbustivo no levantamento florístico. Foram estimadas a densidade absoluta e relativa, frequência absoluta e relativa para ambas as comunidades. Após o levantamento florístico prévio, realizou-se a coleta de 40 nódulos da raiz das espécies de Calliandra fasciculata e 23 de Moldenhawera emarginata. Em seguida, realizou-se o isolamento das bactérias dos nódulos provenientes das espécies C. fasciculata e M. emarginata. Foram avaliadas as características culturais dos isolados e a partir dos dados, foi possível agrupar os isolados por meio de um dendrograma cultural com a utilização do coeficiente de Jaccard, pelo software MVSP (Multivariate Stastitical Package). Três espécies leguminosas foram registradas em ambos as comunidades, totalizando 1.192 indivíduos distribuídos dentre C. fasciculata (com 1080 ind.), M. emarginata (com 86 ind.) e Periandra mediterranea (com 26 ind.). Contudo, na espécie P. mediterranea não foi constatada nodulação em campo. A espécie C. fasciculata foi responsável por 92,62% do total de indivíduos. A partir das características morfológicas avaliadas, dos 23 isolados de C. fasciculata, obteve-se 6 grupos culturais. Este resultado sugere alta diversidade morfofisiológica de bactérias fixadoras de nitrogênio nodulando essa espécie em ambiente de campo rupestre quartzítico. Devido à importância desta espécie, recomenda-se seu uso em projetos de recuperação, especialmente em ambientes semelhantes ao deste estudo. Palavras-chave: endemismo; Fabaceae; nitrogênio; nodulação.   Nodulating legumes with potential for use in the recovery of degraded areas in quartzite rocky fields   ABSTRACT: The objective of this work was to evaluate the composition and structure of leguminous species in the vegetal formation of rocky fields in Serra do Espinhaço Meridional, as well as to verify the diversity of nitrogen-fixing bacteria of the nodular species. The floristic survey was carried out in a reserve area based in the municipality of Conceição do Mato Dentro, Minas Gerais. The region is located on the eastern edge of the Serra do Espinhaço Meridional and has a Cwa climate. Twenty-five fixed plots (10 × 10 m) were installed for the shrub-tree compartment and 60 fixed plots (1 × 2 m) for the herb-subshrub compartment to carry out the floristic survey. Absolute and relative density, absolute and relative frequency were estimated for both compartments. After the previous floristic survey, 40 root nodules of the species of Calliandra fasciculata and 23 of Moldenhawera emarginata were collected. Afterward, bacteria were isolated from the nodules of C. fasciculata and M. emarginata. The cultural characteristics of the isolates were evaluated and from the data, it was possible to group the isolates through a cultural dendrogram using the Jaccard coefficient, using the MVSP (Multivariate Statistical Package) software. Three leguminous species were recorded in both compartments, totaling 1192 individuals distributed among C. fasciculata (with 1080 ind.), M. emarginata (with 86 ind.) and Periandra mediterranea (with 26 ind.). However, for the species P. mediterranea, no nodulation was observed in the field. The species C. fasciculata was responsible for 92.62% of the total number of individuals. From the morphological characteristics successfully evaluated, of the 23 isolates of C. fasciculata, 6 cultural groups were obtained. This result suggests high morphophysiological diversity of nitrogen-fixing bacteria nodulating this species in a quartzite rock field environment. Due to the importance of this species, its use in recovery projects is recommended, especially in environments similar to the one in this study. Keywords: endemism; Fabaceae; nitrogen; nodulation

ANTIOXIDANTS, SUCROSE AND AGAR IN THE IN VITRO MULTIPLICATION OF Eremanthus incanus

The objective of this study was to evaluate the in vitro multiplication of Eremanthus incanus axillary buds in the presence of PVP additives and activated charcoal under the interaction of different sucrose and agar concentrations. Explants containing axillary buds were inoculated in MS culture medium to evaluate the effect of 0.8 g L-1 of PVP and 1.0, 2.0 and 4.0 g L-1 of activated charcoal. The results of the addition of 0, 15, 30, and 60 g L-1 of sucrose combined with concentrations of 6 and 10 g L-1 of agar in MS medium were also evaluated. The number and quality of emitted shoots were evaluated after 30 and 60 days. The addition of PVP to the culture medium was more efficient than the use of activated charcoal in the multiplication of the species. The presence of sucrose is indispensable for developing the shoots well, and the use of a lower concentration of agar favors the development of quality shoots. The best results for shoot multiplication were obtained using 30 g L-1 sucrose and 6 g L-1 agar. PVP, activated charcoal, agar and sucrose are important components in the culture medium and alter the in vitro multiplication of Eremanthus incanus.The objective of this study was to evaluate the in vitro multiplication of Eremanthus incanus axillary buds in the presence of PVP additives and activated charcoal under the interaction of different sucrose and agar concentrations. Explants containing axillary buds were inoculated in MS culture medium to evaluate the effect of 0.8 g L-1 of PVP and 1.0, 2.0 and 4.0 g L-1 of activated charcoal. The results of the addition of 0, 15, 30 and 60 g L-1 of sucrose combined with concentrations of 6 and 10 g L-1 of agar in MS medium were also evaluated. The number and quality of emitted shoots were evaluated after 30 and 60 days. The addition of PVP to the culture medium was more efficient than the use of activated charcoal in the multiplication of the species. The presence of sucrose is indispensable for developing the shoots well, and the use of a lower concentration of agar favors the development of quality shoots. The best results for shoot multiplication were obtained using 30 g L-1 sucrose and 6 g L-1 agar. PVP, activated charcoal, agar and sucrose are important components in the culture medium and alter the in vitro multiplication of Eremanthus incanus

IMPACT OF CLIMATE CHANGE ON THE POTENTIAL DISTRIBUTION OF NATIVE AND INVASIVE GRASSES IN THE CERRADO

Biological invasion, mainly by African grasses, is one of the main threats to the Cerrado's biodiversity. The objective of this study was to elucidate the distribution patterns of the exotic grass Melinis minutiflora and the native grass Trichanthecium cyanescens, in order to verify the areas of potential occurrence of these species and, thus, to infer if their potential distribution will be affected by climate changes. Species occurrence data and ten uncorrelated climatic variables referring to the forecasts for the current period and future forecasts (2050 and 2070) were used for the analysis of the modeling. The models indicated the existence of environmental suitability, with AUCs above 0.8 (good) being observed in M. minutiflora and above 0.9 (excellent) in T. cyanescens. It is concluded that climate change may have negative impacts on the geographic distribution of these species, reducing the area of environmental suitability for them. In addition, the species studied have similar areas of potential distribution and regularly overlap, which can make M. minutiflora a threat to the conservation of T. cyanences, due to the invasion potential of the first

Avaliação da regeneração natural em nascentes perturbadas no município de Lavras, MG.

This work aimed at evaluating the natural regeneration dynamics in two springs in process of recovery in Lavras-MG, surrounded in December/2003. To do that, two springs were carried out from August/2005 (18 months) to April/2006 (24 months). 122 plots in the total of 5 x 5m (25m2) were plotted, being 76 plots in spring 1 and 46 plots in spring 2. The plots were distributed systematically throughout all the area of the springs. All individuals with height larger than 0.10 m and DBH lower than 5 cm were identified, having their diameters and height measured. Floristic composition, structural analyses and natural regeneration dynamics were studied. In the total, 524 individuals from 24 family and 55 species were sampled. The Asteraceae family was distinguished in species number in spring 1 and the families Fabaceae Faboideae, Myrtaceae and Solanaceae in spring 2. The species Baccharis dracunculifolia and Vernonia ferruginea presented the highest natural regeneration indexes in spring 1, while the species Vernonia polyanthes and Nectandra nitidula in spring 2. The higher diversity index was registered for the spring 2 in the second evaluation, having an increase from 3,324 (first evaluation) to 3,384 (second evaluation). The floristic similarity index registered between the springs was of 20.0% and 18.5% for the evaluations 1 and 2, respectively. During the time of monitoring, it was verified a significant increase of 33.33% and 15.8% in individuals number sampled in springs 1 and 2, respectively. The natural regeneration method presents potential for the recovering of the vegetation of the two springs; however, it is necessary the adoption of control techniques of Brachiaria sp. grass.Este trabalho teve como objetivo avaliar a dinâmica da regeneração natural em duas nascentes em processo de recuperação no município de Lavras, MG. Para tanto, foram realizados dois inventários após o isolamento das áreas, nos períodos de Agosto/2005 (18 meses) e Abril/2006 (24 meses). Foram alocadas no total 122 parcelas de 5´5 m (25 m2), sendo 76 na nascente 1 e 46 parcelas na nascente 2. As parcelas foram distribuídas de forma sistemática ao longo de toda a área das nascentes. Todos os indivíduos com altura superior a 0,10 m e DAP (diâmetro a altura do peito) < 5 cm, foram identificados, tendo seus diâmetros e alturas mensuradas. Foram avaliadas a composição florística, a estrutura, e a dinâmica da regeneração natural. Foram amostrados no total 524 indivíduos pertencentes a 24 famílias e 55 espécies. A família Asteraceae se destacou em número de espécies na nascente 1 e as famílias Fabaceae Faboideae, Myrtaceae e Solanaceae na nascente 2. As espécies Baccharis dracunculifolia e Vernonia ferruginea apresentaram os maiores índices de regeneração natural, na nascente 1, enquanto que as espécies Vernonia polyanthes e Nectandra nitidula se destacaram na nascente 2. O maior índice de diversidade foi registrado para a nascente 2 na segunda avaliação, aumentando de 3,324 (primeira avaliação) para 3,384 (segunda avaliação). O índice de similaridade florística encontrado entre as duas nascentes, foi de 20,0 e 18,5% para as avaliações 1 e 2 respectivamente. Durante o período de monitoramento, verificou-se um aumento significativo de 33,33 e 15,8% no número de indivíduos amostrados nas nascentes 1 e 2 respectivamente. O método da regeneração natural apresenta grande potencial para a recuperação da vegetação no entorno das duas nascentes, sendo necessária, no entanto, a adoção de técnicas de controle do capim Brachiaria sp

DINÂMICA DA VEGETAÇÃO COLONIZADORA EM TRÊS ÁREAS DEGRADADAS PELO GARIMPO NA SERRA DO ESPINHAÇO MERIDIONAL

A avaliação do processo de sucessão vegetal em locais degradados constitui uma importante ferramenta para se definirem estratégias de recuperação. Assim, considerando-se o quadro atual de degradação nos ecossistemas florestais, o presente trabalho objetivou estudar a dinâmica da composição florística da vegetação colonizadora, em três áreas degradadas em processo de regeneração natural, na Serra do Espinhaço Meridional. No primeiro inventário, foram amostrados todos os indivíduos arbóreo-arbustivo com DAS30 ≥ 3 cm. No segundo inventário, foram registrados os indivíduos mortos, remensurados os sobreviventes e mensurados e identificados os indivíduos recrutados (DAS30 ≥ 3 cm). Foram calculadas as taxas de dinâmica: mortalidade, recrutamento, ganho e perda em área basal e número de indivíduos para cada área. Os valores de H’ obtidos para as áreas foram comparados aos pares pelo teste de t de Hutcheson. O padrão observado nas três áreas foi semelhante e as alterações mais expressivas durante os dois inventários foram o aumento significativo da densidade e o rápido aumento da área basal total. Todos os indicadores estruturais analisados mostraram que as áreas estão em processo de construção inicial, porém a área degradada pelo garimpo de ouro encontra-se em estágio sucessional mais avançado quando comparada à área degradada pelo processo de voçorocamento e à área degradada pelo garimpo de diamante.Palavras-chave: composição florística; impactos antrópicos; heterogeneidade temporal; sucessão ecológica. COLONIZING VEGETATION DYNAMICS IN THREE AREAS DEGRADED BY MININGIN SOUTHERN SERRA DO ESPINHAÇO ABSTRACT: The evaluation of the process of plant succession in degraded places is an important tool to define recovery strategies. Thus, considering the current situation of degradation in forest ecosystems, the present study aimed to study the dynamics of the floristic composition of the colonizing vegetation, in three degraded areas in the process of natural regeneration, in the Serra do Espinhaço Meridional. In the first inventory, all tree-shrub individuals with DAS30 ≥ 3 cm were sampled. In the second inventory, dead individuals were recorded, survivors were remeasured and recruited individuals were measured and identified (DAS30 ≥ 3 cm). The dynamics rates were calculated: mortality, recruitment, gain and loss in the basal area and number of individuals for each area. The H 'values obtained for the areas were compared in pairs by the Hutcheson t test. The pattern observed in the three areas was similar and the most significant changes during the two inventories were the significant increase in density and the rapid increase in the total basal area. All the structural indicators analyzed showed that the areas are in the process of initial construction, but the area degraded by gold mining is in a more advanced successional stage when compared to the area degraded by the voçorocamento process and the area degraded by diamond mining.Keywords: floristic composition; human impacts; temporal heterogeneity; ecological succession