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1.
Sci Rep ; 12(1): 17245, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36241638

RESUMO

Schinus terebinthifolia Raddi is a species with several potential uses; selecting the proper substrate and fertilizer rate can be vital for seedling production in a nursery environment. This study aims to evaluate two substrates, namely: (i) sewage sludge (SS) from Ilha WWTP; (ii) a commercial substrate (CS) made of organic materials (mainly sphagnum peat). Increasing rates of controlled-release fertilizer - CRF (0, 3, 6, and 12 kg m-3) were applied. The experiment was completely randomized with a factorial 2 × 4 scheme (substrates × rates). The seedlings' growth, biomass, and quality were evaluated. The treatments were compared by Tukey test and regression analysis, where linear, quadratic, and cubic models were considered. Principal components analysis (PCA) and cluster analysis were performed. The CRF rates showed non-significant effects for most of the investigated variables in the SS substrate. In the CS, a 7.8 kg m-3 rate of CRF showed the best growth performance. The multivariate analysis of the morphological parameters proved suitable as a complementary approach to evaluate the seedlings' quality. Seedlings reached recommended values for height, diameter, and quality in the 100% SS substrate without chemical fertilizers; thus, Schinus terebinthifolia production in the SS from Ilha is recommended. Besides the growth advantage, the SS can promote nursery cost savings with commercial substrates and chemical fertilizers.


Assuntos
Anacardiaceae , Esgotos , Preparações de Ação Retardada , Fertilizantes , Plântula , Solo
2.
Environ Monit Assess ; 192(4): 219, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32146533

RESUMO

Several environmental impacts are resulting from the process of anthropization and climate variability that have caused degradation of biomes and humid environments. Thus, the objective of this study was to evaluate the effect of the anthropic process and the variation of climatic conditions on the dynamics of the marsh vegetation in the Pandeiros River preservation area in the north of Minas Gerais, Brazil. The Enhanced Vegetation Index (EVI) of product MOD13Q1 and the gross primary productivity (GPP) of product MOD17A2 of the Moderate Resolution Imaging Spectroradiometer (MODIS) were used for the period from 2001 to 2017 were used in this process. Rain and air temperature data were obtained from the Conventional Weather Station of Januária-MG. The time series were submitted to the nonparametric statistical test of Mann-Kendall. The process of anthropization of the swamp area in the environmental protection area of the Pandeiros River/MG (EPA) showed a pattern of expansion of vegetation cover associated with the reduction of the water table, a phenomenon resulting from the silting process and reduction of the incidence of rain in this region, which contributes to the reduction of ecosystem services. Thus, understanding the influence of climatic variables on the dynamics of vegetation in humid environments, such as the EPA swamp area on the Pandeiros River, is essential for the preservation and recovery of these ecosystems and for the implementation of public policies for preservation and conservation.


Assuntos
Clima , Ecossistema , Rios , Brasil , Monitoramento Ambiental , Áreas Alagadas
3.
Environ Monit Assess ; 190(11): 688, 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-30377834

RESUMO

This study aimed to analyze the spectral trend of vegetation with rainfall in El Niño-Southern Oscillation events (ENSO) in the Atlantic Forest, Brazil. Monthly rainfall data were collected from 85 conventional meteorological stations (EMC), data from the Enhanced Vegetation Index 2 (EVI2) and ENSO events (El Niño, La Niña, and Neutral) in the period from 2001 to 2013. Afterwards, state cluster analysis was performed using the results of non-parametric tests. The Mann-Kendall (MK) non-parametric test did not identify a trend pattern in rainfall distribution in the Atlantic Forest. The results for EVI2 by state and region showed that the trend is decreasing in the Northeast Region, except for the states of Alagoas and Pernambuco. Southeast region showed an increasing trend of EVI2 (except for Rio de Janeiro and São Paulo), while the South region showed a decreasing trend. In the Midwest, the trend was significantly decreasing. In the prognosis elaborated for the future, the regions with significant declines of the vegetation were the Northeast and Midwest. This study shows that the Atlantic Forest in some regions of Brazil has been suffering from the growing urbanization process and there is a trend of soil degradation.


Assuntos
El Niño Oscilação Sul , Monitoramento Ambiental/métodos , Chuva , Floresta Úmida , Tecnologia de Sensoriamento Remoto/métodos , Brasil , Ecossistema
4.
Biosci. j. (Online) ; 34(3): 751-760, mai/jun. 2018. ilus, tab, graf
Artigo em Inglês | LILACS | ID: biblio-966992

RESUMO

The objective of this study was to analyze a spatiotemporal study of the vegetation dynamics of the hydrographic basin of the Ribeirão Cachimbal in Rio de Janeiro (Brazil), based on Moderate-Resolution Imaging Spectroradiometer imagery acquired by the TERRA satellite. A total of 23 images were used for each year of El Niño (2005 and 2015), 250-m-resolution images from collection 006 of the 16-day Enhanced Vegetation Index (MOD13Q1) product were used. Daily rainfall and temperature data were obtained from a conventional meteorological station at Resende (Rio de Janeiro State), which were made available by the National Institute for Meteorology of Brazil. Simple linear regression analysis was performed to evaluate the dependence of the temporal series of vegetation as a function of the daily series of rainfall and temperature in terms of the significance of their correlation coefficients. Multivariate analysis of the main components was also undertaken. The results of the simple linear regression between the vegetation index and meteorological variables (temperature and rainfall) were significant in the respective years (p-value < 5%), except for rainfall in 2015, which presented a value of 0.06 (p-value < 25%). Observing the trend, both years (2005 and 2015 showed an increase in vegetation in the study area (Z = 0.37 and 0.24, respectively). By quantifying the values of the respective vegetation classes, it was possible to verify that a reduction of 40% had occurred in areas with dense vegetation coverage by 2015. The vegetation dynamics of the Ribeirão Cachimbal basin are influenced by rainfall and temperature variables and they have greatest correlation in spring and summer.


O objetivo deste estudo foi de analisar espaço-temporalmente a dinâmica da vegetação da bacia hidrográfica do Ribeirão Cachimbal, Rio de Janeiro, Brasil. Foram utilizadas um total de 23 imagens para cada ano de El Niño (2005 e 2015) do sensor Moderate-Resolution Imaging Spectroradiometer a bordo do satélite TERRA, da coleção 006 com resolução espacial de 250 metros do produto de 16 em 16 dias Enhanced Vegetation Index (MOD13Q1). Os dados de chuva e temperatura diários foram obtidos da Estação Meteorológica Convencional de Resende, Rio de Janeiro, disponibilizados pelo Instituto Nacional de Meteorologia. Foi realizada uma análise de regressão linear simples para avaliar a dependência da série temporal da vegetação em função das séries diárias de chuva e de temperatura e a significância dos coeficientes de correlação. E também uma análise multivariada dos componentes principais. O resultado da regressão linear simples entre as variáveis índice de vegetação e meteorológicas (temperatura e chuva), foram significativas nos respectivos anos (p-value < 5%), exceto para a variável chuva no ano de 2015 que apresentou 0,06% para um p-value menor que 25%. Observando a tendência, em ambos os anos (2005 e 2015) foi verificado o aumento da vegetação na área de estudo (Z = 0,37 e 0,24). Quando quantificados os valores das respectivas classes de vegetação podese verificar que ocorreu uma redução de 40% da classe Dense vegetation em 2015. A dinâmica da vegetação da bacia do ribeirão Cachimbal é influenciada pelas variáveis climáticas chuva e temperatura, sendo a maior correlação na estação de primavera e verão.


Assuntos
Bacias Hidrográficas , Ecossistema , Ecologia
5.
Biosci. j. (Online) ; 34(2): 268-278, mar./apr. 2018.
Artigo em Inglês | LILACS | ID: biblio-966636

RESUMO

The objective of this study was to characterize the physical parameters of the Cachimbal River Watershed, located in Pinheiral, Rio de Janeiro State, Brazil, and to use the resulting data to identify degradation risks. To achieve this purpose, a Hydrologically Consistent Digital Elevation Model (HCDEM) was generated using contour line, river path, and area boundary data extracted from topographic maps of the cities of Volta Redonda (Page SF-23-ZAV-2) and Piraí (Page SF-23-Z-VI-1). These maps were obtained from the Brazilian Institute of Geography and Statistics, and were rendered at a scale of 1:50,000 ArcGISs version 10.5 software was used to generate the HCDEM, from which the physical parameters were extracted. Results showed that the altitude of the area ranges from 360 m to 740 m, while the slope varies heterogeneously from 6% to 28%. The sub-basin has a total area of 104.15 km², a perimeter of 63.41 km, a main channel length of 21.79 km, and a 5th-order dendritic drainage network. Other parameters include a compactness coefficient of 1.74, a form factor of 0.34, and a circularity ratio of 0.33. These values indicate that the sub-basin is not prone to floods because of its elongated shape. Meanwhile, drainage density was 2.60 km km-2, while river density was 5.5 channels km-2; these parameters indicate excellent performance and high potential to generate new channels. Although the roughness coefficient indicates that the area is suitable for agricultural development, the roughness index demonstrates the need to adopt more nuanced agricultural practices that account for the particular features of the area, such as topographic variation and soil characteristics.


O objetivo deste estudo foi caracterizar os parâmetros físicos da sub-bacia hidrográfica do ribeirão Cachimbal, Pinheiral-RJ, Brasil, a fim de se identificar os riscos à degradação. Para isso foi gerado o Modelo Digital de Elevação Hidrologicamente Consistente (MDEHC) através a partir das cartas topográficas dos municípios de Volta Redonda (Folha SF-23-Z-A-V-2) e Piraí (Folha SF-23-Z-VI-1), obtidas no Instituto Brasileiro de Geografia e Estatística na escala de 1:50.000, onde foram extraídas as curvas de nível, rios e limite. A confecção foi realizada utilizando o software ArcGIS versão 10.5. A obtenção dos parâmetros físicos foi realizada sob o MDEHC. Verificou-se que a altimetria varia de 360m a 740m e a declividade de 6% a 28%, estando elas apresentando padrão de distribuição heterogêneo. A sub-bacia possui área total de 104.15 km², perímetro de 63.41 km, com comprimento do canal principal de 21.79 km e rede de drenagem de 5ª ordem, com padrão dendrítico; coeficiente de compacidade (Kc) de 1.74; coeficiente de forma (Kf) de 0.34, índice de circularidade (IC) de 0.33; que indicam que a sub bacia não apresenta propensão a enchentes, pois possui formato alongado. Os valores encontrados para densidade de drenagem (Dd) foram de 2.60 km km-2 e a para densidade hidrográfica (Dh) de 5.5 canais km-2, o que classificou a área com Dd muito boa e Dh com elevado potencial para gerar novos canais. Dessa forma o escoamento superficial ocorre de forma lenta, e a formação de processos erosivos ocorre gradualmente. Apesar do coeficiente de rugosidade (Cr) indicar aptidão agrícola para agricultura, o índice de rugosidade (Ir) verificado, demonstra a necessidade da adoção de um conjunto de práticas agrícolas mais conservacionistas, levando em levando em consideração as particularidades da área, com destaque para as variações do relevo e características do solo associadas à paisagem da bacia hidrográfica.


Assuntos
Erosão , Bacias Hidrográficas , Escoamento Superficial
6.
Biosci. j. (Online) ; 33(1): 169-176, jan./feb. 2017. ilus, graf, tab
Artigo em Inglês | LILACS | ID: biblio-965885

RESUMO

Evidence of environmental impact on the Cerrado is characterised by the presence of large homogeneous pastures and agricultural areas, with the presence of very fragmented and scattered forest fragments. When these areas are abandoned due to low productivity, natural regeneration begins, which is influenced by environmental factors. The goal of the present study was to evaluate the forest cover temporal dynamics in anthropogenic areas and the influence of climate on natural regeneration in the Cerrado. The study site was an anthropogenic area that has been protected against the entrance of domestic animals and agriculture since 2002. Environments were identified, and natural regeneration dynamics were analysed by the use of vegetation indices calculated from satellite images. Statistical analysis Non-parametric Mann-Kendall was used to check the trend of the rain and the Normalized Difference Vegetation Index, multivariate analysis to verify the correlations and groups between the years of occurrence of El Niño and La Niña and the values of Normalized Difference Index. Natural regeneration in the Cerrado increased over time and was positively correlated with rainfall incidence. The process of recovery of degraded areas by natural regeneration technique proved efficient in the Cerrado, however, natural regeneration is negatively influenced by the weather phenomenon El Niño.


No Cerrado a evidencia dos impactos ambientais são as grandes áreas homogêneas com pastagens e agricultura, com a presença de fragmentos florestais muito fragmentados e esparsos. Quando as áreas são abandonadas devido à baixa produtividade, inicia-se o processo de regeneração natural, com influência dos fatores ambientais. Assim, o objetivo desse estudo foi avaliar a dinâmica temporal da cobertura florestal em áreas antropizadas e a influência das condições climáticas no processo de regeneração natural no Cerrado. Para tanto, foi utilizada uma área antropizada protegida contra a entrada de animais domésticos e explorações agrícolas desde 2002. A identificação dos ambientes e a dinâmica do processo de regeneração natural foram obtidas por meio de imagens orbitais com o cálculo do índice de vegetação. A análise estatística não-paramétrica de Mann-Kendall foi utilizada para verificar a tendência da chuva e do Normalized Difference Vegetation Index, a análise multivariada para verificar as correlações e agrupamentos entre os anos de ocorrência de El Niño e La Niña e os valores do Normalized Difference Index. A dinâmica do processo de regeneração natural no Cerrado apresentou um padrão crescente em função do tempo e uma correlação positiva com a incidência de chuvas. O processo de recuperação de áreas degradadas pela técnica de regeneração natural mostrou se eficiente no Cerrado, no entanto, a regeneração natural é influenciada negativamente pelo fenômeno climático El Niño.


Assuntos
Plantas , Pastagens , Clima , Pradaria , Meio Ambiente
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