ABSTRACT
To restore invaded areas, planting fast-growing native species such as Senegalia polyphylla (DC.) Britton & Rose (Fabaceae) is widely used. However, invasive grasses reduce light availability, alter fire regimes, and compete for water and nutrients, hindering the growth of native trees. Fertilization practices influence the competition dynamics between natives and invasives by altering soil fertility. Therefore, this study investigated the effects of mineral and organic fertilization on the nutritional status and growth of S. polyphylla cultivated during the first 120 days after transplanting. The experiment was conducted in a completely randomized design comprising five treatments and four replications, along with the unfertilized control (0-0%) as an additional treatment. Dystrophic red latosol and different proportions of mineral and organic fertilizers were used. The variables evaluated included dry mass of aboveground parts and roots, nutrient content in leaves, and nutrient use efficiency. The results showed that fertilizations with high nutrient concentrations (100-0% and 75-25%) resulted in greater accumulation of N, P, and K in the leaves, while balanced fertilization (50-50% and 25-75%) led to greater root dry mass. These results emphasize the importance of strategically choosing fertilizer formulations to promote the healthy development of seedlings in areas subject to interference from invasive grasses.
ABSTRACT
Pteridium aquilinum (Dennstaedtiaceae) colonization affects ecological and restoration processes. The knowledge of the impacts on the ecological succession by this species allows the use of restoration strategies in invaded environments. This work aimed to evaluate the floristic composition, diversity, structure, density, basal area, height, and diameter of natural regeneration in three areas of the Atlantic Forest in the Serra do Espinhaço Biosphere Reserve in an area invaded by P. aquilinum after a fire. Three environments with different coverage intensities by P. aquilinum were studied, and the plants over 10 cm in height or 5 cm in canopy diameter were measured. The floristic composition and diversity were analyzed using indices presented by Chao, Fisher, Margalef, Pielou, Shannon-Weaver, and Simpson, and similarity was evaluated by the Jaccard index. Species density, basal area, height, and canopy diameter classes were also evaluated. The floristic composition, diversity, structure of natural regeneration, density, and basal area were higher in post-fire areas with a lower coverage by P. aquilinum. The topsoil coverage with plant litter and the possible effect of P. aquilinum allelopathy probably reduced the species richness and diversity. The proportion of plants from the lowest height and canopy diameter classes was higher under moderate coverage by P. aquilinum. The reduction in the floristic composition, diversity, number of species, and basal area in post-fire areas colonized by P. aquilinum is probably due to this species aggressiveness. The population of this plant is high, accumulating large quantities of plant litter as a physical barrier preventing light and propagules from reaching the soil, reducing the germination of the seed bank and, consequently, the natural regeneration. The floristic composition, diversity, structure of natural regeneration, density, and basal area were lower in areas with higher coverage by P. aquilinum. The proportion of plants in the most significant height and canopy diameter classes was higher with reduced coverage by P. aquilinum. The P. aquilinum reduced forest succession in areas after a fire.
Subject(s)
Fires , Pteridium , Forests , Plants , SoilABSTRACT
Trifluralin, a pre-emergent herbicide, is widely used in Brazil in the weed grass management in restoration areas. The objective was to evaluate the tolerance of Piptadenia gonoacantha to trifluralin. The treatments had three trifluralin doses (445, 890, and 1335 g a.i. ha-1), applied in pre-sowing, as well as the control, without herbicide. Visual intoxication, seed germination, survival rate, emergence speed index (EMI), mean germination period, seedling height, and diameter, micromorphometric parameters of plant roots collected at 60 d after sowing, root length (RL) and volume, leaf area (LA), leaf numbers, root and shoot dry matter, and fluorescence of chlorophyll a at 30, 45, and 60 d after sowing were analyzed. Visual intoxication values above 50% were observed only with 1335 g a.i. ha-1. The herbicide did not affect seed germination, EMI, average germination period, seedling height, and diameter, root micromorphometric parameters, length, dry matter or root volume, and chlorophyll a fluorescence. The dose 1335 g a.i. ha-1 caused a reduction of 41.5% in survival, 50.3% in the LA, 36.7% in the number of leaves (LN), and 59.8% in the aerial dry mass of seedlings. The trifluralin presents potential for restoration programs of degraded areas with this forest species.
Subject(s)
Fabaceae , Herbicides , Biodegradation, Environmental , Brazil , Chlorophyll A , Germination , Seedlings , Seeds , TrifluralinABSTRACT
Clomazone has excelled among Brazilian non-target-site herbicides with high environmental impact. Its high solubility in water can result in leaching, contaminating groundwater and watercourses with possible riparian forest degradation. This situation can be mitigated by phytoremediation process. This study aimed to identify tree species tolerant to clomazone aiming to use them in bioremediation programs. Twelve forest species were evaluated: Inga marginata Willd, Handroanthus serratifolius (A.H. Gentry) S. Grose, Jacaranda puberula Chan, Cedrela fissilis Vell, Calophyllum brasiliense Cambess, Psidium myrsinoides Berg, Tibouchina granulosa Cogn, Caesalpinia ferrea Mart ex. Tul, Caesalpinia pluviosa DC, Terminalia argentea Mart & Zucc, Schinopsis brasiliensis Eng and Schizolobium parahyba (Vell). The statistical analysis was performed in a completely randomized block design with four replications. Three clomazone applications were made each 20 days (60, 80 and 100 days after planting); each application was equivalent to one-half of the recommended rate (2.0 L ha-1). The evaluated parameters were plant height, stem diameter, leaf number, leaf area and dry biomass. The forest species survived the clomazone application; and I. marginata, C. ferrea and S. brasiliensis showed increased tolerance to this herbicide, demonstrating potential for phytoremediation of areas contaminated by clomazone.
Entre os herbicidas com elevado impacto ambiental em sítios não alvo no Brasil, o clomazone tem se destacado. A alta solubilidade desse herbicida em água pode resultar em lixiviação, ocasionando contaminação de mananciais de água subterrânea e cursos d'água, com possível degradação de matas ciliares. Esta circunstância pode ser mitigada por meio de processos de fitorremediação. Este trabalho objetivou identificar espécies arbóreas tolerantes ao clomazone visando utiliza-las em programas de biorremediação. Foram avaliadas doze espécies florestais: Inga marginata Willd, Handroanthus serratifolius (A.H. Gentry) S.Grose, Jacaranda puberula Chan, Cedrela fissilis Vell, Calophyllum brasiliense Cambess, Psidium myrsinoides Berg, Tibouchina granulosa Cogn, Caesalpinia ferrea Mart ex. Tul, Caesalpinia pluviosa DC, Terminalia argentea Mart & Zucc, Schinopsis brasiliensis Eng e Schizolobium parahyba (Vell) Blake. Foi utilizado o delineamento em blocos ao acaso com quatro repetições. Foram feitas 3 aplicações do herbicida clomazone com intervalos de 20 dias (aos 60, 80 e 100 dias após o plantio), cada aplicação foi correspondente a metade da dose comercial de 2.0 L ha-1. Foram avaliados a altura da planta, o diâmetro do caule, o número de folhas, a área foliar e o acúmulo de biomassa seca. Constatou-se que todas as espécies sobreviveram à aplicação de clomazone, contudo I. marginata, C. ferrea e S. brasiliensis apresentaram maior tolerância ao herbicida, demonstrando potencial para o uso em programas de fitorremediação de áreas contaminadas pelo clomazone.
Subject(s)
Biodegradation, Environmental , Percolation , HerbicidesABSTRACT
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.
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.
Subject(s)
Aspidosperma/growth & development , Seedlings/growth & development , Plant Shoots/growth & development , Plants/anatomy & histologyABSTRACT
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.(AU)
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.(AU)
Subject(s)
Aspidosperma/growth & development , Seedlings/growth & development , Plants/anatomy & histology , Plant Shoots/growth & developmentABSTRACT
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: 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
O objetivo deste trabalho foi avaliar a flora arbustiva-arbórea em um fragmento de floresta estacional semidecidual na região da Serra do Espinhaço para propor espécies para recuperação das áreas degradadas pela exploração de minério de ferro em ecossistemas congêneres. O levantamento florístico e estrutural da vegetação arbustivo-arbórea foi realizado em setembro de 2007 por meio do método dos pontos quadrantes, tendo como critério de inclusão altura do fuste superior a 1,3 m. Os indivíduos foram estratificados entre adulto (DAP ≥ 5,0 cm) e juvenil (DAP < 5,0 cm). Foram amostrados 90 pontos, onde foram identificadas 94 espécies, 70 gêneros e 32 famílias botânicas. Para o índice de diversidade de Shannon, os valores apresentados para cada compartimento foram 3,96 nat.ind-1 e 3,94 nat.ind-1; e a equabilidade de Pielou foi de 0,896 e 0,938, respectivamente, para os estrados juvenil e adulto. As famílias que mais se destacaram quanto ao número de espécies foram Myrtacea (17), Fabaceae (12), Rubiaceae (8), Euphrobiaceae (6), Sapindaceae (5) e Lauraceae (5). Para a recuperação da área foram selecionados sete grupos de espécies que serão utilizados. As características das espécies foram suficientes para a definição de grupos funcionais que poderão ser utilizados na recuperação de áreas degradadas.
The objective of this study was to evaluate the tree flora in a fragment of semi deciduous forest in the region of the Espinhaço, with aim to propose species for restoration of areas degraded by mining exploitation of iron in similar ecosystems. The inventory floristic and structural of vegetation of shrubs and trees was conducted in September 2007, by the quadrants-point method according to the method of minimum distances, whose inclusion criterion of the stem above the height 1.3 m. The individual were stratified into adults (DBH ≥ 5.0 cm) and juvenile (DBH <5.0 cm). We sampled 90 points, which were identified 94 species, 70 genera and 32 families. For the diversity index of Shannon, values presented for each layer were 3.96 nats.ind-1 and 3.94 nats.ind-1, and equability of Pielou were 0.896 and 0.938, respectively for layer juvenile and adult. Families that stood out by the number of species were Myrtaceae (17), Fabaceae (12), Rubiaceae (8), Euphrobiaceae (6), Sapindaceae (5) and Lauraceae (5). For the recovery area were selected seven groups of species that will be used for recuperation of degraded areas. The characteristics of the species were sufficient for the definition of functional groups that can be used in recuperation of degraded areas.
Subject(s)
Crop Production , Forests , Environmental Restoration and Remediation , Iron , MiningABSTRACT
O objetivo do trabalho foi avaliar o uso da Amostragem Adaptativa Cluster (AAC) na quantificação de indivíduos adultos de Caryocar brasiliense Camb. (Pequi), em comparação aos métodos de amostragem tradicionais. Foi feito um censo com mapeamento dos indivíduos adultos de pequi em uma área de cerrado de 36,5ha no Parque Estadual do Rio Preto/MG. O mapa gerado foi divido em unidades de 20×20m no qual foram testadas cinco alternativas de amostragem utilizando a Amostragem Casual Simples, Amostragem Sistemática e Amostragem Adaptativa Cluster. A comparação entre elas foi feita através do teste F de Graybill a 1% de significância, considerando os parâmetros precisão e exatidão. Todas as alternativas apresentaram boa exatidão, sendo a Amostragem Adaptativa Cluster, com condição de inclusão igual a 2, a mais precisa.(AU)
In this study adult individuals of Caryocar brasiliense (pequi) were quantified by (AAC) and they were compared the traditional sampling methods. Census of adult individuals of pequi in a savannah area of 36.5ha in Black River State Park / MG was transformed in map. Thus map was divided into cells of 20x20m where five alternative of sampling were tested using simple Random Sampling, Systematic Sampling and Adaptative Cluster Sampling. Comparision among them was done by F test Graybill 1% of significance, considering precision and accuracy as parameters. All alternatives showed good accuracy, and the Adapatative Cluster Sampling with a condition of inclusion equal to 2 was most accurate.(AU)
Subject(s)
Sampling Studies , Grassland , FruitABSTRACT
O objetivo do trabalho foi avaliar o uso da Amostragem Adaptativa Cluster (AAC) na quantificação de indivíduos adultos de Caryocar brasiliense Camb. (Pequi), em comparação aos métodos de amostragem tradicionais. Foi feito um censo com mapeamento dos indivíduos adultos de pequi em uma área de cerrado de 36,5ha no Parque Estadual do Rio Preto/MG. O mapa gerado foi divido em unidades de 20×20m no qual foram testadas cinco alternativas de amostragem utilizando a Amostragem Casual Simples, Amostragem Sistemática e Amostragem Adaptativa Cluster. A comparação entre elas foi feita através do teste F de Graybill a 1% de significância, considerando os parâmetros precisão e exatidão. Todas as alternativas apresentaram boa exatidão, sendo a Amostragem Adaptativa Cluster, com condição de inclusão igual a 2, a mais precisa.
In this study adult individuals of Caryocar brasiliense (pequi) were quantified by (AAC) and they were compared the traditional sampling methods. Census of adult individuals of pequi in a savannah area of 36.5ha in Black River State Park / MG was transformed in map. Thus map was divided into cells of 20x20m where five alternative of sampling were tested using simple Random Sampling, Systematic Sampling and Adaptative Cluster Sampling. Comparision among them was done by F test Graybill 1% of significance, considering precision and accuracy as parameters. All alternatives showed good accuracy, and the Adapatative Cluster Sampling with a condition of inclusion equal to 2 was most accurate.
Subject(s)
Sampling Studies , Fruit , GrasslandABSTRACT
Este trabalho foi realizado em três áreas degradadas em processo de regeneração natural em Diamantina, MG. O objetivo do trabalho foi relacionar a distribuição da abundância das espécies colonizadoras com as variáveis ambientais. As comunidades das áreas degradadas pelo garimpo de diamante (ADGD) e ouro (ADGO), assim como, pelo processo de voçorocamento (ADV) contou com 50 (10 x 10 m), 30 (10 x 10 m) e 36 (5 x 3m) parcelas, respectivamente, nas quais foram mensurados todos os indivíduos arbustivo-arbóreos vivos encontrados nas parcelas com DAS30 3 cm. Da mesma forma, em cada parcela, foi coletada uma amostra composta do substrato superficial (0-20 cm), sendo analisados os parâmetros físicos, químicos e topográficos. Para analisar as correlações entre os gradientes ambientais e vegetacionais foi empregada a Análise de Correspondência Canônica (CCA). No geral foram amostrados 1.152 indivíduos, pertencentes a 16 famílias e 38 espécies, sendo 153 indivíduos, 5 famílias e 9 espécies pertencentes a ADGD; 921 indivíduos, 16 famílias e 36 espécies pertencentes a ADGO e 78 indivíduos, 9 famílias e 11 espécies pertencentes a ADV. Verificou-se que houve relação entre os gradientes ambientais e a abundância e composição florística da vegetação colonizadora, ficando a maioria das espécies mais fortemente correlacionada com as variáveis desnível, M.O, m e umidade.
This study was conducted in three areas degraded in the process of natural regeneration in Diamantina, MG. The aimed of work was to relate the abundance distribution of the colonizing species with environmental variables. The communities of areas degraded by mining diamond (ADGD) and gold (ADGO), as well as the process of voçorocamento (ADV) had 50 (10 x 10 m), 30 (10 x 10 m) and 36 (5 x 3m) plots respectively were measured all individuals shrubs and trees living found in plots with DAS30 3 cm. Likewise, in each plot, a composite sample was collected from the substrate surface (0-20 cm) were analyzed the physical and chemical parameters. To analyze the correlations between environmental gradients and vegetation was used Canonical Correspondence Analysis (CCA). Overall 1152 individuals were sampled, belonging to 16 families and 38 species, and, 153 individuals, families 5 and 9 species of ADGD, 921 individuals, 16 families and 36 species belonging to ADGO and 78 individuals, 9 families and 11 species belonging ADV. There was a relationship between environmental gradients and floristic composition and abundance of colonizing vegetation, most species being more strongly correlated with the variables elevation M.O, m and moisture.
Subject(s)
Multivariate Analysis , Environment , Environmental Restoration and RemediationABSTRACT
Herbicidas com conhecida ação seletiva têm sido utilizados no controle de plantas daninhas em reflorestamentos. Diante disso, este trabalho teve como objetivo avaliar a sensibilidade de algumas espécies arbóreas de interesse comercial e na recuperação de áreas degradadas ao glyphosate, visando à adequação de métodos mais eficientes no controle de plantas daninhas. Para a realização do experimento foram utilizadas quatro espécies: Plathymenia reticulata, Bowdichia virgilioides, Kielmeyera lathrophyton e Solanum lycocarpum. Foram estudados os efeitos da aplicação das quatro doses do glyphosate (0, 160, 480, 1440 g ha-1) sobre as variáveis: intoxicação das plantas, altura, diâmetro na altura do coleto, número de folhas e anatomia foliar. Para a caracterização anatômica das espécies foram realizados cortes nas folhas dos indivíduos remanescentes de Solanum lycocarpum, Kielmeyera lathrophyton e Bowdichia virgilioides. Os sintomas mais evidentes foram a clorose e necrose foliar, sendo S. lycocarpum a espécie que mais sofreu com a ação do herbicida. A maior mortalidade foi observada para a S. lycocarpum, sendo que todos os indivíduos que receberam as maiores doses dos tratamentos de glyphosate morreram. A presença de sintomas de intoxicação e o normal desenvolvimento das mudas de Plathymenia reticulata, Bowdichia virgilioides, Kielmeyera lathrophyton são indícios de que estas espécies são tolerantes ao glyphosate.
Herbicides with known selective action have been used to control weeds in reforestation. Thus, this study evaluated the sensitivity of some tree species of commercial interest and the recovery of degraded areas to glyphosate, aiming at adapting the most efficient methods to control weeds. To perform the experiment four species were selected, namely: Plathymenia reticulata, Bowdichia virgilioides, Kielmeyera lathrophyton and Solanum lycocarpum. The effect of the application of four doses of glyphosate (0, 160, 480, 1440 g ha-1) on the variables: intoxication, plant height, height diameter collect, leaf number and leaf anatomy. For anatomical characterization of the species were also carried out on the leaves of Solanum lycocarpum individuals remaining, Kielmeyera lathrophyton and Bowdichia virgilioides. The most obvious symptoms were leaf chlorosis and necrosis, S. lycocarpum being the species most affected by the action of the herbicide. The highest mortality rate was observed for S. lycocarpum, and all individuals who received higher doses of glyphosate treatments died. The symptoms of intoxication and the normal development of seedlings Plathymenia reticulata, Bowdichia virgilioides, Kielmeyera lathrophyton are indications that these species are tolerant to glyphosate.
Subject(s)
Conservation of Natural Resources , Weed Control , HerbicidesABSTRACT
Historically, forest landscapes have been modified by human activities, causing its destruction and fragmentation to exploit its resources. However, forests play a vital role in protecting the environment, especially on slops, hilltops, lakes, springs and river banks. This study aimed to understand the diversity and structure of vegetation on a slope of riparian forest in Bocaina de Minas, MG and identify key environmental variables that influence the spatial distribution of individual trees. An inventory of the tree community was conducted, in which ten of 10m×40m plots were allocated and systematically distributed throughout the study area. All individuals existing shrubs and trees within the plots with 1.30m diameter ≥ 5.0cm of soil were sampled in order to generate information on the horizontal structure, richness and diversity of the community. Variables related to the substrata were obtained for each plot from the topography and laboratory analysis of soil samples (pH, levels of P, K, Ca, Mg and Al, base saturation (V), organic matter and levels of sand, silt and clay). Other variables such as distance from the river and successional stage of the plots, were also evaluated. In order to correlate environmental variables with the abundance distribution of the species, a canonical correspondence analysis (CCA) and Spearman correlation were used. The Shannon diversity index (H') and evenness index (J') obtained were 3.53 and 0.76, respectively. The emerging patterns of environmental variables and the abundance of species indicate that these were distributed throughout the fragment, mainly due to the P content in soil and successional stage of the plots. In addition, several species have produced significant correlations between their abundance in the plots and the variables related to successional stage, variations in soil, and distance from the banks of water courses.
Historicamente, as paisagens florestais têm sido modificadas pela ação do homem, causando sua destruição e fragmentação ao explorar seus recursos. No entanto, as florestas têm papel fundamental de proteção ao meio ambiente, principalmente em encostas, topos de morros, lagos, nascentes e às margens de rios. O presente trabalho teve como objetivo conhecer a diversidade e a estrutura da vegetação de uma mata ciliar de encosta em Bocaina de Minas (MG) e identificar as principais variáveis ambientais que influenciam na distribuição espacial das espécies. Realizou-se um inventário da comunidade arbórea no período de 5 a 20 de junho de 2004, onde foram alocadas dez parcelas de 10m×40m, distribuídas sistematicamente por todo o fragmento. Todos os indivíduos arbustivo-arbóreos existentes no interior das parcelas com diâmetro a 1,30m do solo ≥ 5,0cm foram amostrados. Variáveis relacionadas ao substrato (pH, teores de P, K, Ca, Mg e Al, V, MO, areia, silte e argila) foram obtidas para cada parcela a partir de análises laboratoriais de amostras do solo. Outras variáveis como distância do rio e estágio sucessional também foram avaliadas. Para correlacionar as variáveis ambientais com a distribuição da abundância das espécies, foram utilizadas técnicas de análise de correspondência canônica (CCA) e correlação de Spearman. Os valores para os índices de diversidade de Shannon (H') e equabilidade de Pielou (J') obtidos foram 3,53 e 0,76. Os padrões emergentes das variáveis ambientais e a abundância das espécies indicam que estas se distribuíram ao longo do fragmento, principalmente em função do teor de P no solo e do estágio sucessional das parcelas. Além disso, várias espécies produziram correlações significativas entre sua abundância nas parcelas e as variáveis referentes ao estágio sucessional, variações edáficas químicas, texturais e distância até as margens dos cursos d'água.