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Emmanuel Fritsch - One of the best experts on this subject based on the ideXlab platform.
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Kaolinite dating from Acrisol and Ferralsol: A new key to understanding the landscape evolution in NW Amazonia (Brazil)
Geoderma, 2020Co-Authors: Emmanuel Fritsch, Madeleine Selo, Nádia Regina Do Nascimento, Thierry AllardAbstract:Abstract Ferralsols and Acrisols are major types of soils of the Amazon basin observed on various landform units comprising plateau surfaces, incised hills at their edges and slopes. The present study focuses on an Acrisol developed on plateaus surfaces from northwest Amazonia and a Ferralsol from the convex hills of the incised plateau edges. Local geomorphologic models of weathering covers suggest that Ferralsols are younger than plateau Acrisols but the absolute chronology of their formation is still lacking. This type of information is however critical to understand the evolution of northwest Amazon Basin landscapes and to identify its link with major climatic and geomorphologic events. In this article, kaolinite-rich samples from soils and saprolites belonging to a transect in the Sao Gabriel da Cachoeira region (Amazon state, Brasil) are investigated. Based on their crystal-chemical characters, several types of kaolinites are identified. Using a previously developed methodology based on electron paramagnetic resonance (EPR) spectroscopy, crystallization ages are proposed for these different kaolinites. Saprolite kaolinites are dated from 6 to 3.6 Ma in the Acrisol profile and display significantly more recent ages (
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Podzolization as a deferralitization process: dynamics and chemistry of ground and surface waters in an Acrisol : Podzol sequence of the upper Amazon Basin
European Journal of Soil Science, 2008Co-Authors: N.r Do Nascimento, Emmanuel Fritsch, C. Grimaldi, M. Bardy, G.t. Bueno, A.j MelfiAbstract:Hydrochemical processes involved in the development of hydromorphic Podzols are a major concern for the upper Amazon Basin because of the extent of the areas affected by such processes and the large amounts of organic carbon and associated metals exported to the rivers. The dynamics and chemical composition of ground and surface waters were studied along an Acrisol-Podzol sequence lying in an open depression of a plateau. Water levels were monitored along the sequence over a period of 2 years by means of piezometers. Water was sampled in zero-tension lysimeters for groundwater and for surface water in the drainage network of the depression. The pH and concentrations of organic carbon and major elements (Si, Fe and Al) were determined. The contrasted changes reported for concentrations of Si, organic carbon and metals (Fe, Al) mainly reflect the dynamics of the groundwater and the weathering conditions that prevail in the soils. Iron is released by the reductive dissolution of Fe oxides, mostly in the Bg horizons of the upslope Acrisols. It moves laterally under the control of hydraulic gradients and migrates through the iron-depleted Podzols where it is exported to the river network. Aluminium is released from the dissolution of Al-bearing minerals (gibbsite and kaolinite) at the margin of the podzolic area but is immobilized as organo-Al complexes in spodic horizons. In downslope positions, the quick recharge of the groundwater and large release of organic compounds lead to acidification and a loss of metals (mainly Al), previously stored in the Podzols.
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podzolization as a deferralitization process a study of an acrisol podzol sequence derived from palaeozoic sandstones in the northern upper amazon basin
European Journal of Soil Science, 2004Co-Authors: Emmanuel Fritsch, G.t. Bueno, A.j Melfi, N Do R Nascimento, A J Herbillon, Th Allard, R Astolfo, H BoucherAbstract:Morphological, geochemical and mineralogical studies were carried out in a representative soil catena of the low-elevation plateaux of the upper Amazon Basin to interpret the steps and mechanisms involved in the podzolization of low-activity clay soils. The soils are derived from Palaeozoic sandstones. They consist of Hydromorphic Podzols under tree savannah in the depressions of the plateaux and predominantly of Acrisols covered by evergreen forest elsewhere. Incipient podzolization in the uppermost Acrisols is related to the formation of organic-rich A and Bhs horizons slightly depleted in fine-size particles by both mechanical particle transfer and weathering. Weathering of secondary minerals by organic acids and formation of organo-metallic complexes act simultaneously over short distances. Their vertical transfer is limited. Selective dissolution of aluminous goethite, then gibbsite and finally kaolinite favour the preferential cheluviation of first Fe and secondly Al. The relatively small amount of organo-metallic complexes produced is related to the quartzitic parent materials, and the predominance of Al over Fe in the spodic horizons is due to the importance of gibbsite in these low-activity clay soils. Morphologically well-expressed podzols occur in strongly iron-depleted topsoils of the depression. Mechanical transfer and weathering of gibbsite and kaolinite by organic acids is enhanced and leads to residual accumulation of sands. Organo-metallic complexes are translocated in strongly permeable sandy horizons and impregnate at depth the macro-voids of embedded soil and saprolite materials to form the spodic Bs and 2BCs horizons. Mechanical transfer of black particulate organic compounds devoid of metals has occurred later within the sandy horizons of the podzols. Their vertical transfer has formed well-differentiated A and Bh horizons. Their lateral removal by groundwater favours the development of an albic E horizon. In an open and waterlogged environment, the general trend is therefore towards the removal of all the metals that have initially accumulated as a response to the ferralitization process and have temporarily been sequestrated in organic complexes in previous stages of soil podzolization.
A.j Melfi - One of the best experts on this subject based on the ideXlab platform.
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Podzolization as a deferralitization process: dynamics and chemistry of ground and surface waters in an Acrisol : Podzol sequence of the upper Amazon Basin
European Journal of Soil Science, 2008Co-Authors: N.r Do Nascimento, Emmanuel Fritsch, C. Grimaldi, M. Bardy, G.t. Bueno, A.j MelfiAbstract:Hydrochemical processes involved in the development of hydromorphic Podzols are a major concern for the upper Amazon Basin because of the extent of the areas affected by such processes and the large amounts of organic carbon and associated metals exported to the rivers. The dynamics and chemical composition of ground and surface waters were studied along an Acrisol-Podzol sequence lying in an open depression of a plateau. Water levels were monitored along the sequence over a period of 2 years by means of piezometers. Water was sampled in zero-tension lysimeters for groundwater and for surface water in the drainage network of the depression. The pH and concentrations of organic carbon and major elements (Si, Fe and Al) were determined. The contrasted changes reported for concentrations of Si, organic carbon and metals (Fe, Al) mainly reflect the dynamics of the groundwater and the weathering conditions that prevail in the soils. Iron is released by the reductive dissolution of Fe oxides, mostly in the Bg horizons of the upslope Acrisols. It moves laterally under the control of hydraulic gradients and migrates through the iron-depleted Podzols where it is exported to the river network. Aluminium is released from the dissolution of Al-bearing minerals (gibbsite and kaolinite) at the margin of the podzolic area but is immobilized as organo-Al complexes in spodic horizons. In downslope positions, the quick recharge of the groundwater and large release of organic compounds lead to acidification and a loss of metals (mainly Al), previously stored in the Podzols.
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podzolization as a deferralitization process a study of an acrisol podzol sequence derived from palaeozoic sandstones in the northern upper amazon basin
European Journal of Soil Science, 2004Co-Authors: Emmanuel Fritsch, G.t. Bueno, A.j Melfi, N Do R Nascimento, A J Herbillon, Th Allard, R Astolfo, H BoucherAbstract:Morphological, geochemical and mineralogical studies were carried out in a representative soil catena of the low-elevation plateaux of the upper Amazon Basin to interpret the steps and mechanisms involved in the podzolization of low-activity clay soils. The soils are derived from Palaeozoic sandstones. They consist of Hydromorphic Podzols under tree savannah in the depressions of the plateaux and predominantly of Acrisols covered by evergreen forest elsewhere. Incipient podzolization in the uppermost Acrisols is related to the formation of organic-rich A and Bhs horizons slightly depleted in fine-size particles by both mechanical particle transfer and weathering. Weathering of secondary minerals by organic acids and formation of organo-metallic complexes act simultaneously over short distances. Their vertical transfer is limited. Selective dissolution of aluminous goethite, then gibbsite and finally kaolinite favour the preferential cheluviation of first Fe and secondly Al. The relatively small amount of organo-metallic complexes produced is related to the quartzitic parent materials, and the predominance of Al over Fe in the spodic horizons is due to the importance of gibbsite in these low-activity clay soils. Morphologically well-expressed podzols occur in strongly iron-depleted topsoils of the depression. Mechanical transfer and weathering of gibbsite and kaolinite by organic acids is enhanced and leads to residual accumulation of sands. Organo-metallic complexes are translocated in strongly permeable sandy horizons and impregnate at depth the macro-voids of embedded soil and saprolite materials to form the spodic Bs and 2BCs horizons. Mechanical transfer of black particulate organic compounds devoid of metals has occurred later within the sandy horizons of the podzols. Their vertical transfer has formed well-differentiated A and Bh horizons. Their lateral removal by groundwater favours the development of an albic E horizon. In an open and waterlogged environment, the general trend is therefore towards the removal of all the metals that have initially accumulated as a response to the ferralitization process and have temporarily been sequestrated in organic complexes in previous stages of soil podzolization.
Edzo Veldkamp - One of the best experts on this subject based on the ideXlab platform.
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soil fertility controls soil atmosphere carbon dioxide and methane fluxes in a tropical landscape converted from lowland forest to rubber and oil palm plantations
Biogeosciences, 2015Co-Authors: Evelyn Hassler, Marife D Corre, Aiyen Tjoa, M Damris, Sri Rahayu Utami, Edzo VeldkampAbstract:Abstract. Expansion of palm oil and rubber production, for which global demand is increasing, causes rapid deforestation in Sumatra, Indonesia, and is expected to continue in the next decades. Our study aimed to (1) quantify changes in soil CO2 and CH4 fluxes with land-use change and (2) determine their controlling factors. In Jambi Province, Sumatra, we selected two landscapes on heavily weathered soils that differ mainly in texture: loam and clay Acrisol soils. In each landscape, we investigated the reference land-use types (forest and secondary forest with regenerating rubber) and the converted land-use types (rubber, 7–17 years old, and oil palm plantations, 9–16 years old). We measured soil CO2 and CH4 fluxes monthly from December 2012 to December 2013. Annual soil CO2 fluxes from the reference land-use types were correlated with soil fertility: low extractable phosphorus (P) coincided with high annual CO2 fluxes from the loam Acrisol soil that had lower fertility than the clay Acrisol soil (P
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soil nitrogen cycling responses to conversion of lowland forests to oil palm and rubber plantations in sumatra indonesia
PLOS ONE, 2015Co-Authors: Kara Allen, Marife D Corre, Aiyen Tjoa, Edzo VeldkampAbstract:Rapid deforestation in Sumatra, Indonesia is presently occurring due to the expansion of palm oil and rubber production, fueled by an increasing global demand. Our study aimed to assess changes in soil-N cycling rates with conversion of forest to oil palm (Elaeis guineensis) and rubber (Hevea brasiliensis) plantations. In Jambi Province, Sumatra, Indonesia, we selected two soil landscapes – loam and clay Acrisol soils – each with four land-use types: lowland forest and forest with regenerating rubber (hereafter, “jungle rubber”) as reference land uses, and rubber and oil palm as converted land uses. Gross soil-N cycling rates were measured using the 15N pool dilution technique with in-situ incubation of soil cores. In the loam Acrisol soil, where fertility was low, microbial biomass, gross N mineralization and NH4+ immobilization were also low and no significant changes were detected with land-use conversion. The clay Acrisol soil which had higher initial fertility based on the reference land uses (i.e. higher pH, organic C, total N, effective cation exchange capacity (ECEC) and base saturation) (P≤0.05–0.09) had larger microbial biomass and NH4+ transformation rates (P≤0.05) compared to the loam Acrisol soil. Conversion of forest and jungle rubber to rubber and oil palm in the clay Acrisol soil decreased soil fertility which, in turn, reduced microbial biomass and consequently decreased NH4+ transformation rates (P≤0.05–0.09). This was further attested by the correlation of gross N mineralization and microbial biomass N with ECEC, organic C, total N (R=0.51–0. 76; P≤0.05) and C:N ratio (R=-0.71 – -0.75, P≤0.05). Our findings suggest that the larger the initial soil fertility and N availability, the larger the reductions upon land-use conversion. Because soil N availability was dependent on microbial biomass, management practices in converted oil palm and rubber plantations should focus on enriching microbial biomass.
N Do R Nascimento - One of the best experts on this subject based on the ideXlab platform.
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podzolization as a deferralitization process a study of an acrisol podzol sequence derived from palaeozoic sandstones in the northern upper amazon basin
European Journal of Soil Science, 2004Co-Authors: Emmanuel Fritsch, G.t. Bueno, A.j Melfi, N Do R Nascimento, A J Herbillon, Th Allard, R Astolfo, H BoucherAbstract:Morphological, geochemical and mineralogical studies were carried out in a representative soil catena of the low-elevation plateaux of the upper Amazon Basin to interpret the steps and mechanisms involved in the podzolization of low-activity clay soils. The soils are derived from Palaeozoic sandstones. They consist of Hydromorphic Podzols under tree savannah in the depressions of the plateaux and predominantly of Acrisols covered by evergreen forest elsewhere. Incipient podzolization in the uppermost Acrisols is related to the formation of organic-rich A and Bhs horizons slightly depleted in fine-size particles by both mechanical particle transfer and weathering. Weathering of secondary minerals by organic acids and formation of organo-metallic complexes act simultaneously over short distances. Their vertical transfer is limited. Selective dissolution of aluminous goethite, then gibbsite and finally kaolinite favour the preferential cheluviation of first Fe and secondly Al. The relatively small amount of organo-metallic complexes produced is related to the quartzitic parent materials, and the predominance of Al over Fe in the spodic horizons is due to the importance of gibbsite in these low-activity clay soils. Morphologically well-expressed podzols occur in strongly iron-depleted topsoils of the depression. Mechanical transfer and weathering of gibbsite and kaolinite by organic acids is enhanced and leads to residual accumulation of sands. Organo-metallic complexes are translocated in strongly permeable sandy horizons and impregnate at depth the macro-voids of embedded soil and saprolite materials to form the spodic Bs and 2BCs horizons. Mechanical transfer of black particulate organic compounds devoid of metals has occurred later within the sandy horizons of the podzols. Their vertical transfer has formed well-differentiated A and Bh horizons. Their lateral removal by groundwater favours the development of an albic E horizon. In an open and waterlogged environment, the general trend is therefore towards the removal of all the metals that have initially accumulated as a response to the ferralitization process and have temporarily been sequestrated in organic complexes in previous stages of soil podzolization.
Hernández Santana, José Ramón - One of the best experts on this subject based on the ideXlab platform.
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Zonificación agroecológica del Coffea arabica en el municipio Atoyac de Álvarez, Guerrero, México
Universidad Nacional Autonóma de México., 2016Co-Authors: González González, Humberto Antonio, Hernández Santana, José RamónAbstract:ResumenLas zonas agroecológicas del Coffea arabica son aquellas que presentan las condiciones y características del potencial biofísico favorables para su producción con óptimos rendimientos. El análisis de las condiciones geomorfológicas, del régimen hidrotérmico y de la cobertura edáfica en el municipio Atoyac de Álvarez, estado de Guerrero, México, y su representación cartográfica, mediante plataformas SIG, permitió identificar las áreas con potencialidades diferenciadas para el cultivo del Coffea arabica con vistas al establecimiento de su zonificación agroecológica. El enfoque sistémico y el procesamiento automatizado de la información propició la identificación de las áreas con potencial óptimo, medio, bajo y muy bajo. Los potenciales con una aptitud natural óptima se localizan en las zonas de montañas bajas, entre 1 100 a 1 500 msnm, con pendientes entre 1.1° hasta 18°, considerándose pendientes suaves y moderadas; con precipitaciones entre los 1 500 a 2 000 mm, en zonas semicálidas con espectro térmico de 18 °C a 22 °C y sobre suelos Acrisoles y con una clave jerarquizada Ah+Bh+Hh/2, con unidad primaria Acrisol. En el municipio la superficie de potenciales óptimos alcanza las 7 163.47 ha; la de medio, las 28 143.75 ha; la de bajo, las 62 130.65 ha, y la de potencial muy bajo unas 58 411.38 ha. Por su contenido, este enfoque y metodología pueden ser implementados en cualquier marco geográfico, adecuándose a las escalas cartográficas y evaluando las distintas apreciaciones agroecológicas, como aportación a las políticas y decisiones gubernamentales o empresariales para la planeación y el fomento de las áreas cafetaleras.AbstractCosta Grande, the largest coffee-producing region in the state of Guerrero, is where the lowest yields are obtained at the state level: An average 249 kg per ha, according to Sagarpa et al. (2011). This may be due not only to the low plant density in the area (approximately 1 274 plants per hectare), but also to the lack of chemical fertilization. It is estimated that chemical fertilizers are applied to only 0.2% of the coffee plants, and only 3% of them benefit from the manure added to the soil. With the aim to establish agro-ecological areas for Coffea arabica (i.e., those with the most favorable agricultural conditions and the highest biophysical potential for optimum yields) a territorial survey was carried out in the municipality of Atoyac de Álvarez, Guerrero analyzing geomorphological, hydrothermal and edaphic maps based on gis platforms. Six map sheets at a scale of 1:50 000 (inegi, 2009) were employed so as to cover the entire area of study. On these maps the altitude, inclination, climate (temperature, rainfall) and soil types that were compatible with the agronomic requirements of Coffea Arabica were identified and marked out. Rainfall, temperature and soil type data were obtained from maps at a scale of 1:250 000 (inegi, 2009) transformed from vector to raster formats so as to facilitate automated processing. For the morphometric evaluation of the relief, a digital elevation model was built with measurements at each 20 m so as to obtain an hypsometric gradient of 100 m and the classification of inclination into four classes: 0.1° to 18° (32%), 18.1° to 25° (33-47%), 25.1° to 40° (48-84%), and over 40° (> 84%). Central to the agro-ecological zoning of coffee is the concept of agro-ecological potential, as the set of quantitative and qualitative requirements on the natural environment conducive to the proper development of the coffee plant. The relationships between the different variables and the determination of their potentials, as well as the physical-geographical zoning of Coffea Arabica, depended on the reclassification of selected variables and their spatial analysis based on GIS using the software ILWIS 3.31 with a view to obtaining an integrated natural potential model. Agro-ecological areas with optimal, medium, low and very low potentials for the production of this variety of coffee were defined. Optimal areas are located at moderate-to-weak mountain slopes (1.1° to 18°) with Acrisols (hierarchical key Ah+Bh+Hh/2) in semi-warm climates (18 ° to 22 °C) with a rainfall regime between 1 500 and 2,000 mm and at an altitude between 1,100 and 1 500 m. They extend over an area of 7 163.47 ha. Medium-potential areas cover 28 143.75 ha, low-potential areas 62 130.65 ha, and very-low potential areas 58 411.38 ha. This agro-ecological zoning of Coffea arabica is a valuable technical instrument based on national and international experiences and information on the natural conditions prevalent in the municipality of Atoyac de Alvarez. The updating of a database on geomorphological, climatic and soil conditions will help to devise strategies for the achievement of higher crop yields. This approach and methodology can be implemented in any geographical setting with the necessary map scales adjustments and evaluation of the local agro-ecological features. It has the potential to contribute to government and business initiatives alike for the planning and management of coffee areas of their promotion
