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Ângelo Carvalho Oliveira - One of the best experts on this subject based on the ideXlab platform.

  • The relationship between cork oak growth patterns and soil, slope and drainage in a cork oak woodland in Southern Portugal
    Forest Ecology and Management, 2008
    Co-Authors: Augusta Costa, Manuel Madeira, Ângelo Carvalho Oliveira
    Abstract:

    Abstract The influence of soil type, slope and drainage on tree growth patterns (density, tree size, crown canopy cover and cork yield) was assessed in a cork oak montado, located in Central-western Portugal, based on a GIS approach followed by field survey. Five soil groups, that is, Arenosols, Regosols, Podzols, Luvisols and Gleysols, combined in three slope classes (flat, undulating and steep) under two different hydromorphic conditions (normal or deficient) were compared based on five cork oak stand parameters using ANOVA and PCA tests. The results showed a clear influence of soil type on cork oak growth patterns (cork yield, basal area, number of trees per hectare, crown canopy cover and circumference at breast height). In Arenosols all parameters showed maximum values and, in contrast, in Gleysols were found the minimum values. For instance, the average of the annual cork production for Gleysols (153 kg ha−1 year−1) was only 70% of the expected annual cork production of Arenosols (219 kg ha−1 year−1) and the average exploited tree density decreased from 56 trees ha−1 in Arenosols to 44 trees ha−1 in Gleysols, for an average exploited tree density of 53 trees ha−1 for the study area. Slope also seems to influence the cork oak growth patterns, as significant statistical differences were found for cork oak growth parameters between slope classes: steep slopes decreased the cork production, the tree size (circumference at breast height) and the tree density. An overall PCA test showed that three main soil groups could be identified: (i) Arenosols and Podzols; (ii) Regosols and (iii) Luvisols and Gleysols, showing that the former, which could allow the tree root development, have a positive influence on the cork oak growth. A two-way analysis of variance, for soil type and slope, showed that the cork yield and the exploited tree density are clearly affected by these two factors interaction.

Masse D. - One of the best experts on this subject based on the ideXlab platform.

  • Diagnostic de contamination des agrosystèmes périurbains de Dakar par les éléments traces métalliques
    Presses Agronomiques de Gembloux, 2016
    Co-Authors: Nr. Hodomihou, Feder F., Masse D., Ke. Agbossou, Gl. Amadji, Ndour-badiane Y., Doelsch E.
    Abstract:

    Diagnosis of periurban Dakar (Senegal) agrosystem contamination by trace elements. Description of the subject. Urban and periurban market gardening is widespread in the Dakar area of Senegal. Repeated long-term application of organic matter results in high inputs of trace elements (TE). Objectives. The aim is to assess TE contamination in suburban agrosystems. Method. At four sites, we compared the Cu, Zn, Pb and Cd content in the surface layers and sublayers of plots cultivated over a long period with the content found in adjacent uncultivated plots. Results. The two prevailing soil types (Arenosol and Fluvisol) were characterized by significantly different background soil geochemical TE content. In the 0 – 20 and 20 – 40 cm soil layers at the four studied sites, TE content was significantly higher (p < 0.05) in the cultivated plots than in the non-cultivated plots. Arenosols showed a significantly higher (p < 0.05) TE content than Fluvisols. An exception to these results was found in cultivated Arenosols, where Cd, Cu, Zn and Pb contamination was observed. This could be explained by the frequent input into these soils of sewage sludge, poultry droppings, and irrigation with only partially treated wastewater. Cadmium contamination of cultivated Fluvisols was the result of regular natural phosphate inputs, as observed throughout the soil profile. Conclusions. Analysis of soils and organic matters would enable adjustment of the quantities of organic matter applied and could lead to a reduction in TE contamination within these agroecosystems

  • Caractérisation des risques de contamination des agrosystèmes périurbains de Dakar par les éléments traces métalliques
    'African Journals Online (AJOL)', 2015
    Co-Authors: Rn Hodomihou, Feder F., Ndour-badiane Y., Doelsch E., Ek Agbossou, Lg Amadji, Cazevieille P, Chevassus-rosset C, Masse D.
    Abstract:

    L’application de produits résiduaires organiques (PRO) améliore la fertilité des sols, mais induit des effets négatifs sur les agrosystèmes, en raison de la présence de contaminants tels que les éléments traces métalliques (ETM). Cette étude vise à évaluer l’influence de deux doses (20 et 60 T.ha-1) d’apport de boue de station d’épuration STEP et de fiente de volaille sur la disponibilité de quatre ETM (Ni, Cd, Cr et Pb) dans un Arenosol et un fluvisol. Une incubation de 88 jours en conditions contrôlées a été conduite sur les deux sols mélangés aux différentes doses de boue et de fiente. La disponibilité des ETM dans les sols incubés a été évaluée par la technique DGT (Diffusive Gradient in Thin films). Les boues ont abaissé le pH des deux sols tandis que les fientes ont alcalinisé l’Arenosol durant les 14 premiers jours d’incubation. Ces PRO ont augmenté les concentrations de Ni, Cd, Pb et Cr disponibles dans les sols. Les  disponibilités du Ni, Cd et Pb sont plus élevées dans l’Arenosol que dans le fluvisol. La boue à 60 T.ha-1 a induit les plus fortes disponibilités en Cd et Pb tandis que la fiente à 60 T.ha-1 a induit les plus fortes disponibilités en Ni et Cr dans les deux sols.Mots clés : Eléments traces métalliques, Arenosol, fluvisol, boue d’épuration, fiente.  CHARACTERIZATION OF CONTAMINATION RISKS OF THE  SUBURBANAGROECOSYSTEMS OF DAKAR BY TRACE ELEMENTSOrganic wastes (OW) spreading improve soil fertility, but can induce negative effects on agroecosystems, due to the presence of contaminants such as trace elements (TE). This study aims to evaluate the impacts of two doses (20 and 60 T.ha-1) of sewage sludge and poultry manure on the availability of four trace elements (Ni, Cd, Cr and Pb) in Arenosol and  fluvisol. Soils mixed with different doses of sewage sludge and poultry manure were incubated for 88 days under controlled conditions. The  availability of trace elements in incubated soils was evaluated by the DGT (Diffusive Gradient in Thin films) technique. Sewage sludge has decreased the pH of both soils while poultry manure induced an alkalinization of Arenosol during the first 14 days of incubation. OW increased Ni, Cd, Pb and Cr availability in the soils. Availability of Ni, Cd and Pb were higher in Arenosol than in the fluvisol. Sewage sludge at 60 T.ha-1 induced the highest availability of Cd and Pb while the poultry manure at 60 T.ha-1 induced the highest availability of Ni and Cr in both soils.Keywords : Trace elements, Arenosol, fluvisol, sewage sludge, poultry manure

Doelsch E. - One of the best experts on this subject based on the ideXlab platform.

  • Diagnostic de contamination des agrosystèmes périurbains de Dakar par les éléments traces métalliques
    Presses Agronomiques de Gembloux, 2016
    Co-Authors: Nr. Hodomihou, Feder F., Masse D., Ke. Agbossou, Gl. Amadji, Ndour-badiane Y., Doelsch E.
    Abstract:

    Diagnosis of periurban Dakar (Senegal) agrosystem contamination by trace elements. Description of the subject. Urban and periurban market gardening is widespread in the Dakar area of Senegal. Repeated long-term application of organic matter results in high inputs of trace elements (TE). Objectives. The aim is to assess TE contamination in suburban agrosystems. Method. At four sites, we compared the Cu, Zn, Pb and Cd content in the surface layers and sublayers of plots cultivated over a long period with the content found in adjacent uncultivated plots. Results. The two prevailing soil types (Arenosol and Fluvisol) were characterized by significantly different background soil geochemical TE content. In the 0 – 20 and 20 – 40 cm soil layers at the four studied sites, TE content was significantly higher (p < 0.05) in the cultivated plots than in the non-cultivated plots. Arenosols showed a significantly higher (p < 0.05) TE content than Fluvisols. An exception to these results was found in cultivated Arenosols, where Cd, Cu, Zn and Pb contamination was observed. This could be explained by the frequent input into these soils of sewage sludge, poultry droppings, and irrigation with only partially treated wastewater. Cadmium contamination of cultivated Fluvisols was the result of regular natural phosphate inputs, as observed throughout the soil profile. Conclusions. Analysis of soils and organic matters would enable adjustment of the quantities of organic matter applied and could lead to a reduction in TE contamination within these agroecosystems

  • Caractérisation des risques de contamination des agrosystèmes périurbains de Dakar par les éléments traces métalliques
    'African Journals Online (AJOL)', 2015
    Co-Authors: Rn Hodomihou, Feder F., Ndour-badiane Y., Doelsch E., Ek Agbossou, Lg Amadji, Cazevieille P, Chevassus-rosset C, Masse D.
    Abstract:

    L’application de produits résiduaires organiques (PRO) améliore la fertilité des sols, mais induit des effets négatifs sur les agrosystèmes, en raison de la présence de contaminants tels que les éléments traces métalliques (ETM). Cette étude vise à évaluer l’influence de deux doses (20 et 60 T.ha-1) d’apport de boue de station d’épuration STEP et de fiente de volaille sur la disponibilité de quatre ETM (Ni, Cd, Cr et Pb) dans un Arenosol et un fluvisol. Une incubation de 88 jours en conditions contrôlées a été conduite sur les deux sols mélangés aux différentes doses de boue et de fiente. La disponibilité des ETM dans les sols incubés a été évaluée par la technique DGT (Diffusive Gradient in Thin films). Les boues ont abaissé le pH des deux sols tandis que les fientes ont alcalinisé l’Arenosol durant les 14 premiers jours d’incubation. Ces PRO ont augmenté les concentrations de Ni, Cd, Pb et Cr disponibles dans les sols. Les  disponibilités du Ni, Cd et Pb sont plus élevées dans l’Arenosol que dans le fluvisol. La boue à 60 T.ha-1 a induit les plus fortes disponibilités en Cd et Pb tandis que la fiente à 60 T.ha-1 a induit les plus fortes disponibilités en Ni et Cr dans les deux sols.Mots clés : Eléments traces métalliques, Arenosol, fluvisol, boue d’épuration, fiente.  CHARACTERIZATION OF CONTAMINATION RISKS OF THE  SUBURBANAGROECOSYSTEMS OF DAKAR BY TRACE ELEMENTSOrganic wastes (OW) spreading improve soil fertility, but can induce negative effects on agroecosystems, due to the presence of contaminants such as trace elements (TE). This study aims to evaluate the impacts of two doses (20 and 60 T.ha-1) of sewage sludge and poultry manure on the availability of four trace elements (Ni, Cd, Cr and Pb) in Arenosol and  fluvisol. Soils mixed with different doses of sewage sludge and poultry manure were incubated for 88 days under controlled conditions. The  availability of trace elements in incubated soils was evaluated by the DGT (Diffusive Gradient in Thin films) technique. Sewage sludge has decreased the pH of both soils while poultry manure induced an alkalinization of Arenosol during the first 14 days of incubation. OW increased Ni, Cd, Pb and Cr availability in the soils. Availability of Ni, Cd and Pb were higher in Arenosol than in the fluvisol. Sewage sludge at 60 T.ha-1 induced the highest availability of Cd and Pb while the poultry manure at 60 T.ha-1 induced the highest availability of Ni and Cr in both soils.Keywords : Trace elements, Arenosol, fluvisol, sewage sludge, poultry manure

Ataide, Manuelle Belmiro - One of the best experts on this subject based on the ideXlab platform.

  • Efeitos estruturadores de recifes arenosos do Polychaeta Sabellaria wilsoni na comunidade de meiofauna e na associação de Nematoda.
    'Revista de Educacao Matematica e Tecnologica Iberoamericana Universidade Federal de Pernambuco', 2012
    Co-Authors: Ataide, Manuelle Belmiro
    Abstract:

    O objetivo do estudo é avaliar o efeito da engenharia de ecossistema causada pelos recifes de Sabellaria wilsoni (Polychaeta: Sabellariidae) na comunidade da meiofauna e na associação de Nematoda na Ilha de Algodoal, Amazônia, Brasil. Dois tipos de recifes arenosos (Cogumelo e Plataforma) bem como o sedimento arenoso circunvizinho de duas praias distintas (terraço de maré baixa e dissipativa) foram estudados. As coletas foram realizadas em junho (estação chuvosa) e dezembro (estação seca) de 2008 em dois perfis perpendiculares à linha de costa em cada local. As amostras obtidas utilizando-se um corer de 3,0cm de diâmetro enterrado até à profundidade de 10cm foram fixadas com formol a 4%, coradas com Rosa de Bengala e triadas em laboratório ao nível de grandes grupos e para o estudo taxonômico foram retirados os 30 primeiros indivíduos de cada réplica. A meiofauna esteve representada por 22 taxa: Acari, Amphipoda, Bivalvia, Cladocera, Copepoda, Cumacea, Gastropoda, Gastrotricha, Hydrozoa, Insecta, Isopoda, Kinorhyncha, Nematoda, Nemertea, Oligochaeta, Ostracoda, Polychaeta, Rotifera, Tanaidacea, Tardigrada, Tunicata e Turbellaria. A densidade média da meiofauna foi de 1774 ind/10cm², sendo Nematoda o táxon dominante em todas as estações e locais. A ANOVA mostrou que dos parâmetros univariados somente a riqueza apresentou diferença significativa entre os ambientes. A PERMANOVA indicou diferenças significativas para as interações entre os ambientes, bem como entre os tipos de recife e praia considerando os ambientes, e interações entre as estações considerando os diferentes tipos de recife e de praia. A associação de Nematoda esteve representada por 2 classes, 9 ordens, 30 famílias, 91 gêneros e 59 espécies. A densidade média da nematofauna foi de 1424 ind/10cm², sendo Daptonema o gênero dominante seguido por Viscosia e Sabatieria. A ANOVA mostrou que dos parâmetros univariados nenhum apresentou diferença significativa entre os ambientes. A PERMANOVA para a nematofauna também indicou diferenças significativas para as interações entre os ambientes, bem como entre os tipos de recife e praia considerando os ambientes, e interações entre as estações considerando os diferentes tipos de recife e de praia. O IndVal, indicou que os gêneros Bathylaimus, Halichoanolaimus, Linhomoeus, Sabatieria e Viscosia são indicadores do ambiente recifal enquanto que Daptonema, Odontophora, Omicronema, Prorhynchonema e Trichotheristus são gêneros indicadores do ambiente praial. Um conjunto de mudanças nos fatores estruturais e abióticos leva à alta diversidade dentro dos recifes indicando a importância de S. wilsoni enquanto engenheiro de ecossistema em ambiente de praia arenosa estuarina no litoral amazônico

  • Efeitos estruturadores de recifes arenosos do Polychaeta Sabellaria wilsoni na comunidade de meiofauna e na associação de Nematoda
    'Revista de Educacao Matematica e Tecnologica Iberoamericana Universidade Federal de Pernambuco', 2012
    Co-Authors: Ataide, Manuelle Belmiro
    Abstract:

    Conselho Nacional de Desenvolvimento Científico e TecnológicoO objetivo do estudo é avaliar o efeito da engenharia de ecossistema causada pelos recifes de Sabellaria wilsoni (Polychaeta: Sabellariidae) na comunidade da meiofauna e na associação de Nematoda na Ilha de Algodoal, Amazônia, Brasil. Dois tipos de recifes arenosos (Cogumelo e Plataforma) bem como o sedimento arenoso circunvizinho de duas praias distintas (terraço de maré baixa e dissipativa) foram estudados. As coletas foram realizadas em junho (estação chuvosa) e dezembro (estação seca) de 2008 em dois perfis perpendiculares à linha de costa em cada local. As amostras obtidas utilizando-se um corer de 3,0cm de diâmetro enterrado até à profundidade de 10cm foram fixadas com formol a 4%, coradas com Rosa de Bengala e triadas em laboratório ao nível de grandes grupos e para o estudo taxonômico foram retirados os 30 primeiros indivíduos de cada réplica. A meiofauna esteve representada por 22 taxa: Acari, Amphipoda, Bivalvia, Cladocera, Copepoda, Cumacea, Gastropoda, Gastrotricha, Hydrozoa, Insecta, Isopoda, Kinorhyncha, Nematoda, Nemertea, Oligochaeta, Ostracoda, Polychaeta, Rotifera, Tanaidacea, Tardigrada, Tunicata e Turbellaria. A densidade média da meiofauna foi de 1774 ind/10cm², sendo Nematoda o táxon dominante em todas as estações e locais. A ANOVA mostrou que dos parâmetros univariados somente a riqueza apresentou diferença significativa entre os ambientes. A PERMANOVA indicou diferenças significativas para as interações entre os ambientes, bem como entre os tipos de recife e praia considerando os ambientes, e interações entre as estações considerando os diferentes tipos de recife e de praia. A associação de Nematoda esteve representada por 2 classes, 9 ordens, 30 famílias, 91 gêneros e 59 espécies. A densidade média da nematofauna foi de 1424 ind/10cm², sendo Daptonema o gênero dominante seguido por Viscosia e Sabatieria. A ANOVA mostrou que dos parâmetros univariados nenhum apresentou diferença significativa entre os ambientes. A PERMANOVA para a nematofauna também indicou diferenças significativas para as interações entre os ambientes, bem como entre os tipos de recife e praia considerando os ambientes, e interações entre as estações considerando os diferentes tipos de recife e de praia. O IndVal, indicou que os gêneros Bathylaimus, Halichoanolaimus, Linhomoeus, Sabatieria e Viscosia são indicadores do ambiente recifal enquanto que Daptonema, Odontophora, Omicronema, Prorhynchonema e Trichotheristus são gêneros indicadores do ambiente praial. Um conjunto de mudanças nos fatores estruturais e abióticos leva à alta diversidade dentro dos recifes indicando a importância de S. wilsoni enquanto engenheiro de ecossistema em ambiente de praia arenosa estuarina no litoral amazônic

Jerzy Jonczak - One of the best experts on this subject based on the ideXlab platform.

  • Comparing quartz silt surface microstructures in two sandy soils in young-glacial landscape of northern Poland
    Soil Science Annual, 2016
    Co-Authors: Jerzy Jonczak, Marek Degórski, Boguslawa Kruczkowska
    Abstract:

    AbstractThe studies on quartz silt surface microstructures using scanning electron microscopy (SEM) were performed in Brunic Arenosol and Gleyic Ortsteinic Podzol, as major components of soil cover of the lower supra-flood terrace of the Słupia River, N Poland. Brunic Arenosols have developed from coarse- and medium-grained fluvioglacial sands, whereas Podzols from aeolian sands of mid-Holocene age, which in some places were covered with younger aeolian deposits. A group of at least 100 randomly selected grains from each soil horizon have been analyzed. The grains were classified into one of the following groups: fresh (type A), grains with the features of chemical weathering (type B), grains coated with scaly-grain incrustations (type C), grains coated with bulbous incrustations (type D), and cracked grains (type E). Parent materials of the investigated soils did not differ significantly in terms of contribution of grain types and type C predominated in both soils. Significant differences were noted in soil solums. Grains covered by scaly-grained incrustations predominated in Brunic Arenosol, which constituted 62–89%. In the profile of Gleyic Ortsteinic Podzol grains type B predominated in AE and E horizons (65–82%), whereas in the remaining horizons grains type C (54–77%).

  • vertical distribution of cu ni and zn in brunic Arenosols and gleyic podzols of the supra flood terrace of the slupia river as affected by litho pedogenic factors
    Forest Research Papers, 2015
    Co-Authors: Jerzy Jonczak
    Abstract:

    The aim of the study was to assess the influence of lithological and pedogenic factors in the shaping of Cu, Ni and Zn distribution patterns in the profiles of Brunic Arenosols and Gleyic Podzols of the lower supra-flood terrace of the Slupia River, which is located outside the range of significant anthropogenic sources of pollution with these metals. The contents of the investigated metals were analysed in aqua regia extracts of samples collected from three profiles of Brunic Arenosols, formed from river sands, and three profiles of Gleyic Podzols, formed from river sands trans- formed by eolian processes. In general, river sands contained higher amounts of Ni and Zn (2.6 - 6.9 mg·kg -1 Ni; 10.3 - 16.2 mg·kg -1 Zn) com- pared to eolian sands (1.2 - 2.4 mg·kg -1 Ni; 3.3 - 17.3 mg·kg -1 ), while the content of copper tended to be higher in eolian sands (1.3 - 1.9 mg·kg -1 ) than river sands (0.1 - 1.5 mg·kg -1 ). The observed differences between the two types of sand are due to the loss of fine granulometric fractions and various minerals during eolian processes. Higher con- centrations of the investigated metals in soil solum as compared to parent material are due to their uptake from deeper parts of the soil by roots and subsequent return to the soil surface as a component of litterfall. Therefore, the highest concentrations of Cu, Ni and Zn were observed in ectohumus. In the mineral component of the soil, the highest con- centrations were observed in organic matter-rich A and B horizons, which indicate close interactions between heavy metals, humic substances and iron oxides. The vertical distribution of the investigated metals in the profiles of Gleyic Podzols indicates their leaching during podzolization. The observed contents of Cu, Ni and Zn, both in Brunic Arenosols and Gleyic Podzols, were lower than the geochemical background, which confirms that anthropogenic contamination of the studied area with these metals is marginal.

  • uwarunkowane litopedogenicznie rozmieszczenie cu ni i zn w profilach leœnych gleb rdzawych i glejobielicowych terasy nadzalewowej s upi vertical distribution of cu ni and zn in brunic Arenosols and gleyic podzols of the supra flood terrace of the s u
    2014
    Co-Authors: Jerzy Jonczak
    Abstract:

    The aim of the study was to assess the influence of lithological and pedogenic factors in the shaping of Cu, Ni and Zn distribution patterns in the profiles of Brunic Arenosols and Gleyic Podzols of the lower supra-flood terrace of the S³upia River, which is located outside the range of significant anthropogenic sources of pollution with these metals. The contents of the investigated metals were analyzed in aqua regia extracts of samples collected from three profiles of Brunic Arenosols, composed of river sands, and three profiles of Gleyic Podzols, composed of river sands transformed by eolian processes. In general, river sands contained higher amounts of Ni and Zn (2.6-6.9 mg·kg -1 Ni; 10.3-16.2 mg·kg -1 Zn) compared to eolian sands (1.2-2.4 mg·kg -1 Ni; 3.3-17.3 mg·kg -1 ), while the content of copper tended to be higher in eolian sands (1.3-1.9 mg·kg -1 ) than river sands (0.1-1.5 mg·kg -1 ). The observed differences between the two types of sand are due to the loss of fine granulometric fractions and various minerals during eolian processes. Higher concentrations of the investigated metals in soil solum as compared to parent material are due to their uptake from deeper parts of the soil by roots and subsequent return to the soil surface by litter fall. Therefore, the highest concentrations of Cu, Ni and Zn were observed in ectohumus. In the mineral component of the soil, the highest concentrations were observed in organic matter-rich A and B horizons, which indicate close interactions between heavy metals, humic substances and iron oxides. The vertical distribution of the investigated metals in the profiles of Gleyic Podzols indicates their leaching during podzolization. The observed contents of Cu, Ni and Zn, both in Brunic Arenosols and Gleyic Podzols, were lower than the geochemical background, which confirms that anthropogenic contamination of the studied area with these metals is marginal.