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Andry Andriamananjara - One of the best experts on this subject based on the ideXlab platform.
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Land management modifies the temperature sensitivity of soil organic carbon, nitrogen and phosphorus dynamics in a Ferralsol
Applied Soil Ecology, 2019Co-Authors: Andry Andriamananjara, Tiphaine Chevallier, Dominique Masse, Herintsitohaina Razakamanarivo, Tantely RazafimbeloAbstract:Abstract Land management and global warming affect the dynamics of soil organic matter (SOM) and nutrients such as nitrogen (N) and phosphorus (P). The effects depend on the type of SOM and on the temperature sensitivity of the SOM mineralization. There is insufficient data on tropical soils, which generally have low nutrient availability, to be able to predict the changes in SOM dynamics and, particularly, N and P availability with global warming. We studied at field scale, the influence of two land management systems, agroforestry (AGF) and traditional slash and burn agriculture (SB) on total carbon (C), available P and total N stocks in the 0–30 cm horizon of a Ferralsol in Madagascar. The soil under AGF stored more C and available P than the soil under SB. There was no clear difference for total N. A soil incubation laboratory experiment tested the effect on SOM mineralization of three factors: (i) land management (AGF or SB), (ii) increasing the temperature from 25 °C to 35 °C, and (iii) adding farmyard manure (FYM). The mineralization was assessed by measurements of microbial soil respiration (CO2), available P (resin P) and total mineral N over a 59 day soil incubation experiment at 25 °C and 35 °C with or without FYM. During incubation, the soil respiration was higher for AGF than for SB but it was slightly less temperature sensitive for AGF (Q10 = 1.2) than for SB (Q10 = 1.4). The incubation temperature did not have a clear effect on the available P for either AGF or SB, suggesting that temperature did not affect P-fixation processes in the Ferralsol studied which had a high P sorption capacity. The temperature sensitivity of N mineralization was quite high in both systems (Q10 = 3.4 after 42 days of incubation). The nutrient cycling processes (immobilization, mineralization) were faster at the higher temperature. Adding FYM increased slightly SOM mineralization and available P and mineral N, although exchange reactions in the Ferralsol limited P availability. Adding FYM modified the temperature sensitivity of SOM mineralization. It increased the temperature sensitivity of soil respiration, especially for AGF, but seemed to decrease the temperature sensitivity of N mineralization. Land use and management of Ferralsols affected the temperature sensitivity of SOM and nutrient dynamics and, in AGF soils, SOM seemed to be less temperature sensitive and have higher levels of nutrients.
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Land management modifies the temperature sensitivity of soil organic carbon, nitrogen and phosphorus dynamics in a Ferralsol
Applied Soil Ecology, 2019Co-Authors: Andry Andriamananjara, Tiphaine Chevallier, Dominique Masse, Herintsitohaina Razakamanarivo, Tantely RazafimbeloAbstract:Land management and global warming affect the dynamics of soil organic matter (SOM) and nutrients such as nitrogen (N) and phosphorus (P). The effects depend on the type of SOM and on the temperature sensitivity of the SOM mineralization. There is insufficient data on tropical soils, which generally have low nutrient availability, to be able to predict the changes in SOM dynamics and, particularly, N and P availability with global warming. We studied at field scale, the influence of two land management systems, agroforestry (AGF) and traditional slash and burn agriculture (SB) on total carbon (C), available P and total N stocks in the 0-30 cm horizon of a Ferralsol in Madagascar. The soil under AGF stored more C and available P than the soil under SB. There was no clear difference for total N. A soil incubation laboratory experiment tested the effect on SOM mineralization of three factors: (i) land management (AGF or SB), (ii) increasing the temperature from 25 degrees C to 35 degrees C, and (iii) adding farmyard manure (FYM). The mineralization was assessed by measurements of microbial soil respiration (CO2), available P (resin P) and total mineral N over a 59 day soil incubation experiment at 25 degrees C and 35 degrees C with or without FYM. During incubation, the soil respiration was higher for AGF than for SB but it was slightly less temperature sensitive for AGF (Q(10) = 1.2) than for SB (Q(10) = 1.4). The incubation temperature did not have a clear effect on the available P for either AGF or SB, suggesting that temperature did not affect P-fixation processes in the Ferralsol studied which had a high P sorption capacity. The temperature sensitivity of N mineralization was quite high in both systems (Q(10) = 3.4 after 42 days of incubation). The nutrient cycling processes (immobilization, mineralization) were faster at the higher temperature. Adding FYM increased slightly SOM mineralization and available P and mineral N, although exchange reactions in the Ferralsol limited P availability. Adding FYM modified the temperature sensitivity of SOM mineralization. It increased the temperature sensitivity of soil respiration, especially for AGF, but seemed to decrease the temperature sensitivity of N mineralization. Land use and management of Ferralsols affected the temperature sensitivity of SOM and nutrient dynamics and, in AGF soils, SOM seemed to be less temperature sensitive and have higher levels of nutrients.
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Effects of a bacterivorous nematode on rice 32 P uptake and root architecture in a high P-sorbing ferrallitic soil
Soil Biology and Biochemistry, 2018Co-Authors: Mahafaka Patricia Ranoarisoa, Thierry Becquer, Christophe Jourdan, Andry Andriamananjara, Christian Morel, Laetitia Bernard, Lilia Rabeharisoa, Koloina Rahajaharilaza, Claude Plassard, Eric BlanchartAbstract:Soil bacterivorous nematodes are key plant mutualists that increase nutrient availability for plants either by enhancing the mineralization of organic compounds (the “mineralization pathway”) or by increasing plant lateral root branching following shifts in internal plant metabolism, and subsequently leading to a higher volume of soil prospected by the roots (the “hormonal pathway”). The effects of these organisms on the nutrition of plants growing in strongly nutrient-deficient ferrallitic soils, especially in soils with limited available inorganic phosphorus (P), are poorly known, as are the pathways involved. In our study, using Oryza sativa (Poaceae) and Acrobeloides sp. (Cephalobidae), we tested the “mineralization” and “hormonal” hypotheses in an acidic P-depleted Ferralsol from the Madagascar highlands. We assessed the effect of nematode inoculation on (i) inorganic P flow from soil to plant using the 32P labelling technique and (ii) plant root architecture using a rhizobox device. We showed that the ability of Acrobeloides sp. to enhance P uptake in plants is strongly limited in Ferralsols. However, when the soil pH was corrected with dolomite, Acrobeloides sp. increased plant P uptake probably through the “mineralization” pathway (higher microbial turnover). Indeed, the L-value increased by 49% in the presence of nematodes and dolomite, suggesting the production of unlabelled plant-available P, probably through a higher net P mineralization when the nematodes were inoculated. Using the rhizobox technique, we also observed increased root length in the presence of nematodes but the specific root length, the tip number and the root branching density did not increase in the presence of nematodes, suggesting that nematodes did not increase plant P uptake and growth in this soil as proposed by the “hormonal” hypothesis. From an ecological intensification perspective, to promote agro-ecological development in tropical regions, our results suggest that amending ferrallitic soils with P-rich organic matter and correcting soil pH with an appropriate amount of dolomite may constitute suitable agronomic actionable triggers to drive the mutualistic activity of bacterivorous nematodes.
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Système de culture à rotation vouandzou-riz pluvial sur les hautes terres de Madagascar. Rôle du vouandzou (Vigna subterranea) sur la biodisponibilité de P dans les Ferralsols
2011Co-Authors: Andry AndriamananjaraAbstract:Face à la pression démographique et la paupérisation sévissant les pays en développement comme le cas de Madagascar, atteindre la sécurité alimentaire n‘est plus une option mais une étape que les agriculteurs et les chercheurs devraient franchir afin d‘affronter la compétition nationale et mondiale. La valorisation des « tanety » peu exploités de type Ferralsols qui représentent la majeure partie des terrains potentiellement cultivables dans les hautes terres malgaches est actuellement une des meilleures alternatives pour sécuriser les agriculteurs et la population de la grande île. En collaborant étroitement avec les agriculteurs, les chercheurs notamment les agronomes devraient proposer un nouveau système agricole qui intègre les contraintes d‘ordre agronomique à savoir d‘une part, les déterminants socio-économiques, mais également les déterminantes biophysiques du système sol-plante. Concernant les cycles de nutriments, la contrainte majeure des Ferralsols concerne le cycle du phosphore (P) et les risques de fixation de cet élément dans ces sols réduisant sa disponibilité pour les plantes. Les légumineuses, par le biais de leur capacité de fixation de l‘azote peuvent avoir un rôle sur l‘augmentation de la biodisponibilité du P dans les Ferralsols. Dans ce cadre, l‘hypothèse principale est que l‘introduction de plantes légumineuses est nécessaire dans les systèmes de culture. Le voandzou ou Vigna subterranea, pourrait jouer ce rôle comme culture de redressement capable d‘améliorer la productivité du système de culture de riz pluvial qui se développe sur les Ferralsols. Les objectifs spécifiques de la thèse sont : i) évaluer l‘effet du système de culture à rotation voandzou-riz pluvial en termes de rendement rizicole et de biodisponibilité du P ; ii) étudier l‘efficacité de la fertilisation organique, minérale et organo-minérale par une analyse comparative ; iii) évaluer l‘aptitude de voandzou en termes d‘efficience d‘utilisation de P (EUP) pour la fixation symbiotique de l‘azote (FSN) ; et iv) identifier les cultivars et écotypes contrastantes en EUP pour la FSN. Les hypothèses de recherche qui sous tendent ces objectifs ont été : - La rotation Vigna subterranea-riz pluvial est possible et durable sur les terres de « tanety » des Hautes Terres malgaches. - La légumineuse (Vigna subterranea) améliore la disponibilité du phosphore dans les sols acides de type Ferralsol. - Une variabilité génotypique de la FSN pour l‘EUP existe chez différents cultivars et écotypes de Vigna subterranea. Des séries d‘expérimentations ont été conduites à l‘échelle rhizosphérique à travers des essais in situ et en mésocosme afin d‘évaluer la potentialité de voandzou comme culture pouvant améliorer la disponibilité de P. Une forte potentialité de voandzou a été confirmée au cours de l‘essai au champ de longue durée où le système de culture à rotation a été comparé avec le système monocultural du riz pluvial avec une fertilisation organique et/ou minérale. Les résultats obtenus ont montré l‘efficacité du système de culture à rotation comparé avec le système monocultural en termes de rendement et de mobilisation de phosphore par une meilleure efficience d‘utilisation en P spécifiquement sous traitement organique combiné avec le TSP. L‘expérimentation en pots sous condition semi-contrôlée a montré que la légumineuse a utilisé plus efficacement le phosphore du sol spécifiquement sous apport organique combiné avec le TSP comparé à la céréale notamment le riz. Cette forte potentialité a été marquée par une meilleure teneur en P plante (augmentation de 20 à 50% du riz pluvial), statut phosphaté et efficience d‘utilisation du P. L‘expérimentation de criblage variétal des 54 cultivars-écotypes de voandzou de Madagascar, de Niger et du Mali sous culture hydroaéroponique ont permi de montrer l‘existence de variabilité génotypique sur le voandzou et d‘identifier les lignées contrastantes ou les cultivars à forte potentialité à la fixation symbiotique de N2 (FSN) pour l‘efficience d‘utilisation du phosphore (EUP). Les cultivars et écotypes de Madagascar ont présenté une forte potentialité par rapport à ceux du Niger et du Mali en termes de nodulation et de biomasse végétale. A l‘issu de cette présélection, quatre cultivars-écotypes ont présenté une meilleure efficience d‘utilisation de la symbiose rhizobienne. Parmi eux, les deux cultivars-écotypes les plus contrastants ont présenté une meilleure consommation d‘O2 des racines nodulées sous P déficient marqué par une forte perméabilité nodulaire à la diffusion en O2, 4 fois plus élevées comparées au P suffisant, et un changement de structure des cellules corticales couplé avec une expression de gène phytate suite à une analyse d‘imagerie sur coupes nodulaires. L‘analyse des sols rhizosphériques et non rhizosphériques, issus d‘une culture en rhizotron, par la méthode d‘échange isotopique 32P a pu mettre en évidence l‘influence de l‘effet rhizosphérique sur la dynamique des ions «phosphate» diffusibles (Pd) entre la phase solide et la solution du sol sous disponibilité limitant en P. Ce qui se traduit par une forte capacité de réapprovisionnement de la solution du sol en Pd suivant le temps d‘échange induisant ainsi à une meilleure nutrition phosphatée du voandzou spécifiquement chez le cultivar 1. Les mécanismes rhizosphériques impliqués dans la mobilisation des ions «phosphate» sont la diffusion par le Pd, l‘acidification par la baisse de pH, la complexation par les anions organiques induisant une faible teneur en Al et Fe et la minéralisation de P organique via la phosphatase. Les résultats de cette étude nous ont permi de montrer la forte potentialité de voandzou exprimée sous faible disponibilité en P avec l‘existence des lignées contrastantes capables d‘influencer la mobilisation de P du sol et d‘intégrer le voandzou dans le système de culture paysanne productif et durable pour l‘amélioration et la restauration de la fertilité des Ferralsols dans les pays tropicaux comme Madagascar.
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Système de culture à rotation Voandzou - riz pluvial sur les Hautes Terres de Madagascar. Rôle du Voandzou (Vigna subterranea) sur la biodisponibilité du phosphore dans les Ferralsols
2011Co-Authors: Andry AndriamananjaraAbstract:Face à la pression démographique et la paupérisation sévissant les pays en développement comme le cas de Madagascar, atteindre la sécurité alimentaire n‘est plus une option mais une étape que les agriculteurs et les chercheurs devraient franchir afin d‘affronter la compétition nationale et mondiale. La valorisation des «tanety» peu exploités de type Ferralsols qui représentent la majeure partie des terrains potentiellement cultivables dans les hautes terres malgaches est actuellement une des meilleures alternatives pour sécuriser les agriculteurs et la population de la grande île. En collaborant étroitement avec les agriculteurs, les chercheurs notamment les agronomes devraient proposer un nouveau système agricole qui intègre les contraintes d‘ordre agronomique à savoir d‘une part, les déterminants socio-économiques, mais également les déterminantes biophysiques du système sol-plante. Concernant les cycles de nutriments, la contrainte majeure des Ferralsols concerne le cycle du phosphore (P) et les risques de fixation de cet élément dans ces sols réduisant sa disponibilité pour les plantes. Les légumineuses, par le biais de leur capacité de fixation de l‘azote peuvent avoir un rôle sur l‘augmentation de la biodisponibilité du P dans les Ferralsols. Dans ce cadre, l‘hypothèse principale est que l‘introduction de plantes légumineuses est nécessaire dans les systèmes de culture. Le voandzou ou Vigna subterranea, pourrait jouer ce rôle comme culture de redressement capable d‘améliorer la productivité du système de culture de riz pluvial qui se développe sur les Ferralsols. Les objectifs spécifiques de la thèse sont : i) évaluer l‘effet du système de culture à rotation voandzou - riz pluvial en termes de rendement rizicole et de biodisponibilité du P ii) étudier l‘efficacité de la fertilisation organique, minérale et organo-minérale par une analyse comparative iii) évaluer l‘aptitude de voandzou en termes d‘efficience d‘utilisation de P (EUP) pour la fixation symbiotique de l‘azote (FSN) iv) identifier les cultivars et écotypes contrastantes en EUP pour la FSN. Les hypothèses de recherche qui sous tendent ces objectifs ont été : - La rotation Vigna subterranea - riz pluvial est possible et durable sur les terres de « tanety » des Hautes Terres malgaches. - La légumineuse (Vigna subterranea) améliore la disponibilité du phosphore dans les sols acides de type Ferralsol - Une variabilité génotypique de la FSN pour l‘EUP existe chez différents cultivars et écotypes de Vigna subterranea . Des séries d‘expérimentations ont été conduites à l‘échelle rhizosphérique à travers des essais in situ et en mésocosme afin d‘évaluer la potentialité de voandzou comme culture pouvant améliorer la disponibilité de P. Une forte potentialité de voandzou a été confirmée au cours de l‘essai au champ de longue durée où le système de culture à rotation a été comparé avec le système monocultural du riz pluvial avec une fertilisation organique et/ou minérale. Les résultats obtenus ont montré l‘efficacité du système de culture à rotati on comparé avec le système monocultural en termes de rendement et de mobilisation de phosphore par une meilleure efficience d‘utilisation en P spécifiquement sous traitement organique combiné avec le TSP. L‘expérimentation en pots sous condition semi-contrôlée a montré que la légumineuse a utilisé plus efficacement le phosphore du sol spécifiquement sous apport organique combiné avec le TSP comparé à la céréale notamment le riz. Cette forte potentialité a été marquée par une meilleure teneur en P plante (augmentation de 20 à 50% du riz pluvial), statut phosphaté et efficience d‘utilisation du P. L‘expérimentation de criblage variétal des 54 cultivars - écotypes de voandzou de Madagascar, de Niger et du Mali sous culture hydroaéroponique ont permis de montrer l‘existence de variabilité génotypique sur le voandzou et d‘identifier les lignées contrastantes ou les cultivars à forte potentialité à la fixation symbiotique de N2 (FSN) pour l‘efficience d‘utilisation du phosphore (EUP). Les cultivars et écotypes de Madagascar ont présenté une forte potentialité par rapport à ceux du Niger et du Mali en termes de nodulation et de biomasse végétale. A l‘issu de cette présélection, quatre cultivars-écotypes ont présenté une meilleure efficience d‘utilisation de la symbiose rhizobienne. Parmi eux, les deux cultivars-écotypes les plus contrastants ont présenté une meilleure consommation d‘O2 des racines nodulées sous P déficient marqué par une forte perméabilité nodulaire à la diffusion en O2, 4 fois plus élevées comparées au P suffisant, et un changement de structure des cellules corticales couplé avec une expression de gène phytate suite à une analyse d‘imagerie sur coupes nodulaires. L‘analyse des sols rhizosphériques et non rhizosphériques, issus d‘une culture en rhizotron, par la méthode d‘échange isotopique 32P a pu mettre en évidence l‘influence de l‘effet rhizosphérique sur la dynamique des ions «phosphate» diffusibles (Pd) entre la phase solide et la solution du sol sous disponibilité limitant en P. Ce qui se traduit par une forte capacité de réapprovisionnement de la solution du sol en Pd suivant le temps d‘échange induisant ainsi à une meilleure nutrition phosphatée du voandzou spécifiquement chez le cultivar 1. Les mécanismes rhizosphériques impliqués dans la mobilisation des ions «phosphate» sont la diffusion par le Pd, l‘acidification par la baisse de pH, la complexation par les anions organiques induisant une faible teneur en Al et Fe et la minéralisation de P organique via la phosphatase. Les résultats de cette étude nous ont permis de montrer la forte potentialité de voandzou exprimée sous faible disponibilité en P avec l‘existence des lignées contrastantes capables d‘influencer la mobilisation de P du sol et d‘intégrer le voandzou dans le système de culture paysanne productif et durable pour l‘amélioration et la restauration de la fertilité des Ferralsols dans les pays tropicaux comme Madagascar
Adolpho José Melfi - One of the best experts on this subject based on the ideXlab platform.
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Influence of pedogenetic processes on the validity of kaolinite crystallinity indices: A case study of an Amazonian Ferralsol-Podzol soil system with white kaolin
Applied Clay Science, 2018Co-Authors: Débora Ayumi Ishida, Antonio Carlos Vieira-coelho, Adolpho José Melfi, Yves Lucas, João Paulo Brasiliano Camargo, Célia Regina MontesAbstract:Abstract Structural defects of kaolinite could be associated with its genetic (weathering, pedogenetic, and hydrothermal) processes. Kaolinite crystallinity indices were evaluated in the context of pedogenetic processes associated with a representative Amazonian Ferralsol-Podzol soil system. This soil system, which is comprised of various types of kaolinitic materials and has a soil dynamics characterized by the progressive replacement of Ferralsols by Podzols, has been evaluated by Hinckley (HI), Aparicio-Galan-Ferrell (AGFI), Lietard (R2), and Amigo (A001) “crystallinity indices” and the “expert system” of Plancon and Zacharie (PZ). The results indicate that the complexity of the kaolinite population, which is due to pedogenetic processes, makes it difficult to interpret the usual kaolinite crystallinity indices. In areas where kaolinites are formed under low aggressive conditions (higher pH and lower dissolved organic carbon, DOC) and in equilibrium with the soil solutions, low-defect phase becomes dominant and there is a good consistency between the “crystallinities” provided by each index. However, in areas where kaolinites are formed under highly aggressive conditions (lower pH and higher DOC), the proportion of low-defect phase decreases. This induces changes in the values of the indices, which do not have the same weight from one index to another.
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Evolution of iron crust and clayey Ferralsol in deeply weathered sandstones of Marília Formation (Western Minas Gerais State, Brazil)
Journal of South American Earth Sciences, 2017Co-Authors: Vania Rosolen, Guilherme Taitson Bueno, Débora Ayumi Ishida, Adolpho José Melfi, Célia Regina Montes, Carla Vanessa De Sousa Coelho, José Silvio GovoneAbstract:Abstract Extensive flat plateaus are typical landforms in the cratonic compartment of tropical regions. Paleoclimate, pediplanation, laterization, and dissection have created complex and distinct geological, geomorphological, and pedological features in these landscapes. In the Brazilian territory, the flat plateau sculpted in sandstone of Marilia Formation (Neocretaceous) belonging to the Sul-Americana surface presents a very clayey and pisolitic Ferralsol (Red and Yellow Latossolo in the Brazilian soil classification). The clayey texture of soil and the pisolites have been considered as weathering products of a Cenozoic detritical formation which is believed to overlay the Marilia Formation sandstones. Using data of petrography (optical microscopy and SEM), mineralogy (RXD), and macroscopic structures (description in the field of the arrangement of horizons and layers), a complete profile of Ferralsol with ferricrete and pisolites was studied. The complex succession of facies is in conformity with a sedimentary structure of Serra da Galga member (uppermost member of Marilia Formation). The hardening hematite concentration appears as layered accretions in the subparallel clayey lenses of sandstone saprolite, preserving its structure. Iron contents varied according to different soil fabrics. Higher concentrations of iron are found in the massive ferricrete or in pisolites in the mottled horizon. Kaolinite is a dominant clay mineral and shows two micro-organizations: (1) massive fabric intrinsic to the sedimentary rock, and (2) reworked in pisolites and illuviated features. The pisolites are relicts of ferricrete in the soft bioturbated topsoil. The continuous sequence of ferricrete from saprolite to the Ferralsol indicates that the regolith is autochthonous, developed directly from sandstones of Marilia Formation, through a long and intense process of laterization.
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Genetic relationships between Ferralsols, podzols and white kaolin in Amazonia
European Journal of Soil Science, 2014Co-Authors: Débora Ayumi Ishida, Yves Lucas, Célia Regina Montes, Osvaldo José Ribeiro Pereira, Patricia Merdy, Adolpho José MelfiAbstract:Summary White kaolin has frequently been observed to be associated with Ferralsol-podzol soil systems in Amazonia. In order to evaluate whether such systems favour kaolin genesis and to identify the associated genetic processes, we studied soil organization, mineralogy and groundwater properties of a Ferralsol-podzol soil system with white kaolin located in the High Rio Negro Basin, Brazil. We found that the kaolin was situated near the Ferralsol-podzol transition and that its thickness was related to the depth of landscape incision by regressive erosion. The kaolin was characterized by silicon, iron and titanium (Ti) leaching and aluminium (Al) absolute accumulation. The groundwater that percolates from the podzol to the kaolin can enhance kaolinite precipitation, by supplying Al originating from kaolinite dissolution in the overlying Bh, and kaolin bleaching, by low pH and Eh of the percolating waters favouring iron reduction. The system dynamics imply that the quartz dissolution rate in the kaolin is of at least the same order of magnitude as the kaolinite dissolution rate in the overlying Bh. Within the whole system, Ti appeared to be very mobile.
Alexia Stokes - One of the best experts on this subject based on the ideXlab platform.
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Do diversity of plants, soil fungi and bacteria influence aggregate stability on ultramafic Ferralsols? A metagenomic approach in a tropical hotspot of biodiversity
Plant and Soil, 2020Co-Authors: Julien Demenois, Alexia Stokes, Luis Merino-martín, Nicolas Fernandez Nuñez, Fabian CarricondeAbstract:Aims Understanding how soil aggregate stability (MWD) is influenced by microbial diversity and abundance can be crucial for ecological restoration in severely disturbed areas. We investigated the relationships between plant and soil microbial diversity and MWD of an ultramafic Ferralsol along a vegetational succession gradient in New Caledonia, where wildfires and extensive nickel mining have degraded the landscape. Methods Five plant communities were studied. For each one, MWD, soil physicochemical parameters (e.g. soil organic carbon (SOC)), plant root traits and fungal abundance were measured. The diversity and structure of plant and microbial communities were respectively assessed via botanical inventories and a metagenomic approach. A generalized linear model (GLM) was used to assess the influence of diversity indexes on MWD. Constrained ordinations (CCA) were performed to assess the influence of communities’ structures on MWD. Results GLM highlighted the linkage between SOC and MWD but did not identify any significant influence of diversity indexes on MWD. CCA revealed a significant influence of communities’ structures, especially the abundance of saprotrophic fungi, on MWD. Conclusions We showed that the structure, but not species richness and diversity of plants, soil fungi and bacteria influence aggregate stability on Ferralsols.
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Do diversity of plants, soil fungi and bacteria influence aggregate stability on ultramafic Ferralsols? A metagenomic approach in a tropical hotspot of biodiversity
Plant and Soil, 2020Co-Authors: Julien Demenois, Alexia Stokes, Luis Merino-martín, Nicolas Fernandez Nuñez, Fabian CarricondeAbstract:Understanding how soil aggregate stability (MWD) is influenced by microbial diversity and abundance can be crucial for ecological restoration in severely disturbed areas. We investigated the relationships between plant and soil microbial diversity and MWD of an ultramafic Ferralsol along a vegetational succession gradient in New Caledonia, where wildfires and extensive nickel mining have degraded the landscape. Five plant communities were studied. For each one, MWD, soil physicochemical parameters (e.g. soil organic carbon (SOC)), plant root traits and fungal abundance were measured. The diversity and structure of plant and microbial communities were respectively assessed via botanical inventories and a metagenomic approach. A generalized linear model (GLM) was used to assess the influence of diversity indexes on MWD. Constrained ordinations (CCA) were performed to assess the influence of communities’ structures on MWD. GLM highlighted the linkage between SOC and MWD but did not identify any significant influence of diversity indexes on MWD. CCA revealed a significant influence of communities’ structures, especially the abundance of saprotrophic fungi, on MWD. We showed that the structure, but not species richness and diversity of plants, soil fungi and bacteria influence aggregate stability on Ferralsols.
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Linkages between root traits, soil fungi and aggregate stability in tropical plant communities along a successional vegetation gradient
Plant and Soil, 2018Co-Authors: Julien Demenois, Freddy Rey, Thomas Ibanez, Alexia Stokes, Fabian CarricondeAbstract:Aims: Determining which abiotic and biotic factors influence soil aggregate stability (MWD) in tropical climates is often confounded by soil type, especially when large amounts of aluminium and iron oxides are present, such as in Ferralsols. We aimed at understanding the role of soil physical and chemical components, vegetation and fungal biomass influencing the aggregate stability of a Ferralsol along a successional gradient of vegetation in New Caledonia. Methods: Five plant communities, ranging from sedge dominated ecosystems to well-established mixed rainforest were studied. For each community, MWD, soil texture, soil organic carbon (SOC), iron and aluminium sesquioxides, root length density (RLD), specific root length (SRL), root mass density (RMD) and fungal biomass were measured. Results:The best prediction of MWD combined abiotic and biotic factors. Along the gradient, Fe increased MWD, while root traits, fungal abundance and SOC modified MWD. From the sedge-dominated community to Arillastrum forest, RMD and SOC increased MWD, while between Nothofagus and mixed rainforest, it was likely that floristic composition and fungal communities influenced MWD. Conclusion : Plant community, the intrinsic nature of Ferralsol and fungal abundance all modified MWD. However, the specific effect of microbial communities should be addressed through a metagenomics approach to elucidate microbial interactions with plant communities.
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Tropical plant communities modify soil aggregate stability along a successional vegetation gradient on a Ferralsol
Ecological Engineering, 2017Co-Authors: Julien Demenois, Freddy Rey, Fabian Carriconde, Alexia StokesAbstract:Soil aggregate stability is viewed as a promising indicator of the restoration status in eroded ecosystems, where the change in plant community composition through successional dynamics is a key driver of ecosystem restoration. In many tropical regions, ecological restoration is an important issue, but the relationship between different types of plant communities and soil aggregate stability is poorly understood. We examined how tropical plant communities modified soil aggregate stability along a successional vegetation gradient on a Ferralsol in New Caledonia. We identified five plant communities, ranging from an early (sedge dominated ecosystems) to a late successional stage (well-established, dense, mixed rainforest). Aggregate stability, total soil organic carbon (SOC) and iron and aluminium sesquioxides were measured in soil originating from each community. Results showed that aggregate stability of the Ferralsol was very high, even on eroded sites, likely due to the high levels of iron and aluminium sesquioxides also found. The levels of iron sesquioxides were particularly high (>10%), due partly to the frequency of wildfires in the region. Total SOC increased from sedgedominated communities (3.5%). Aggregate stability was modified by plant cover and community composition and increased from sparse, early successional vegetation to late successional dense, mixed rainforest. Our study showed that certain plant species have a positive impact on soil aggregate stability and should be considered for ecological restoration on Ferralsols. e.g., Costularia arundinacea, Garcinia amplexicaulis and Myodocarpus fraxinifolius. In conclusion, we suggest that vegetation dynamics should be taken into account when investigating changes in aggregate stability in a context of ecosystem restoration.
Julien Demenois - One of the best experts on this subject based on the ideXlab platform.
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Do diversity of plants, soil fungi and bacteria influence aggregate stability on ultramafic Ferralsols? A metagenomic approach in a tropical hotspot of biodiversity
Plant and Soil, 2020Co-Authors: Julien Demenois, Alexia Stokes, Luis Merino-martín, Nicolas Fernandez Nuñez, Fabian CarricondeAbstract:Aims Understanding how soil aggregate stability (MWD) is influenced by microbial diversity and abundance can be crucial for ecological restoration in severely disturbed areas. We investigated the relationships between plant and soil microbial diversity and MWD of an ultramafic Ferralsol along a vegetational succession gradient in New Caledonia, where wildfires and extensive nickel mining have degraded the landscape. Methods Five plant communities were studied. For each one, MWD, soil physicochemical parameters (e.g. soil organic carbon (SOC)), plant root traits and fungal abundance were measured. The diversity and structure of plant and microbial communities were respectively assessed via botanical inventories and a metagenomic approach. A generalized linear model (GLM) was used to assess the influence of diversity indexes on MWD. Constrained ordinations (CCA) were performed to assess the influence of communities’ structures on MWD. Results GLM highlighted the linkage between SOC and MWD but did not identify any significant influence of diversity indexes on MWD. CCA revealed a significant influence of communities’ structures, especially the abundance of saprotrophic fungi, on MWD. Conclusions We showed that the structure, but not species richness and diversity of plants, soil fungi and bacteria influence aggregate stability on Ferralsols.
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Do diversity of plants, soil fungi and bacteria influence aggregate stability on ultramafic Ferralsols? A metagenomic approach in a tropical hotspot of biodiversity
Plant and Soil, 2020Co-Authors: Julien Demenois, Alexia Stokes, Luis Merino-martín, Nicolas Fernandez Nuñez, Fabian CarricondeAbstract:Understanding how soil aggregate stability (MWD) is influenced by microbial diversity and abundance can be crucial for ecological restoration in severely disturbed areas. We investigated the relationships between plant and soil microbial diversity and MWD of an ultramafic Ferralsol along a vegetational succession gradient in New Caledonia, where wildfires and extensive nickel mining have degraded the landscape. Five plant communities were studied. For each one, MWD, soil physicochemical parameters (e.g. soil organic carbon (SOC)), plant root traits and fungal abundance were measured. The diversity and structure of plant and microbial communities were respectively assessed via botanical inventories and a metagenomic approach. A generalized linear model (GLM) was used to assess the influence of diversity indexes on MWD. Constrained ordinations (CCA) were performed to assess the influence of communities’ structures on MWD. GLM highlighted the linkage between SOC and MWD but did not identify any significant influence of diversity indexes on MWD. CCA revealed a significant influence of communities’ structures, especially the abundance of saprotrophic fungi, on MWD. We showed that the structure, but not species richness and diversity of plants, soil fungi and bacteria influence aggregate stability on Ferralsols.
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Linkages between root traits, soil fungi and aggregate stability in tropical plant communities along a successional vegetation gradient
Plant and Soil, 2018Co-Authors: Julien Demenois, Freddy Rey, Thomas Ibanez, Alexia Stokes, Fabian CarricondeAbstract:Aims: Determining which abiotic and biotic factors influence soil aggregate stability (MWD) in tropical climates is often confounded by soil type, especially when large amounts of aluminium and iron oxides are present, such as in Ferralsols. We aimed at understanding the role of soil physical and chemical components, vegetation and fungal biomass influencing the aggregate stability of a Ferralsol along a successional gradient of vegetation in New Caledonia. Methods: Five plant communities, ranging from sedge dominated ecosystems to well-established mixed rainforest were studied. For each community, MWD, soil texture, soil organic carbon (SOC), iron and aluminium sesquioxides, root length density (RLD), specific root length (SRL), root mass density (RMD) and fungal biomass were measured. Results:The best prediction of MWD combined abiotic and biotic factors. Along the gradient, Fe increased MWD, while root traits, fungal abundance and SOC modified MWD. From the sedge-dominated community to Arillastrum forest, RMD and SOC increased MWD, while between Nothofagus and mixed rainforest, it was likely that floristic composition and fungal communities influenced MWD. Conclusion : Plant community, the intrinsic nature of Ferralsol and fungal abundance all modified MWD. However, the specific effect of microbial communities should be addressed through a metagenomics approach to elucidate microbial interactions with plant communities.
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Tropical plant communities modify soil aggregate stability along a successional vegetation gradient on a Ferralsol
Ecological Engineering, 2017Co-Authors: Julien Demenois, Freddy Rey, Fabian Carriconde, Alexia StokesAbstract:Soil aggregate stability is viewed as a promising indicator of the restoration status in eroded ecosystems, where the change in plant community composition through successional dynamics is a key driver of ecosystem restoration. In many tropical regions, ecological restoration is an important issue, but the relationship between different types of plant communities and soil aggregate stability is poorly understood. We examined how tropical plant communities modified soil aggregate stability along a successional vegetation gradient on a Ferralsol in New Caledonia. We identified five plant communities, ranging from an early (sedge dominated ecosystems) to a late successional stage (well-established, dense, mixed rainforest). Aggregate stability, total soil organic carbon (SOC) and iron and aluminium sesquioxides were measured in soil originating from each community. Results showed that aggregate stability of the Ferralsol was very high, even on eroded sites, likely due to the high levels of iron and aluminium sesquioxides also found. The levels of iron sesquioxides were particularly high (>10%), due partly to the frequency of wildfires in the region. Total SOC increased from sedgedominated communities (3.5%). Aggregate stability was modified by plant cover and community composition and increased from sparse, early successional vegetation to late successional dense, mixed rainforest. Our study showed that certain plant species have a positive impact on soil aggregate stability and should be considered for ecological restoration on Ferralsols. e.g., Costularia arundinacea, Garcinia amplexicaulis and Myodocarpus fraxinifolius. In conclusion, we suggest that vegetation dynamics should be taken into account when investigating changes in aggregate stability in a context of ecosystem restoration.
Fabian Carriconde - One of the best experts on this subject based on the ideXlab platform.
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Do diversity of plants, soil fungi and bacteria influence aggregate stability on ultramafic Ferralsols? A metagenomic approach in a tropical hotspot of biodiversity
Plant and Soil, 2020Co-Authors: Julien Demenois, Alexia Stokes, Luis Merino-martín, Nicolas Fernandez Nuñez, Fabian CarricondeAbstract:Aims Understanding how soil aggregate stability (MWD) is influenced by microbial diversity and abundance can be crucial for ecological restoration in severely disturbed areas. We investigated the relationships between plant and soil microbial diversity and MWD of an ultramafic Ferralsol along a vegetational succession gradient in New Caledonia, where wildfires and extensive nickel mining have degraded the landscape. Methods Five plant communities were studied. For each one, MWD, soil physicochemical parameters (e.g. soil organic carbon (SOC)), plant root traits and fungal abundance were measured. The diversity and structure of plant and microbial communities were respectively assessed via botanical inventories and a metagenomic approach. A generalized linear model (GLM) was used to assess the influence of diversity indexes on MWD. Constrained ordinations (CCA) were performed to assess the influence of communities’ structures on MWD. Results GLM highlighted the linkage between SOC and MWD but did not identify any significant influence of diversity indexes on MWD. CCA revealed a significant influence of communities’ structures, especially the abundance of saprotrophic fungi, on MWD. Conclusions We showed that the structure, but not species richness and diversity of plants, soil fungi and bacteria influence aggregate stability on Ferralsols.
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Do diversity of plants, soil fungi and bacteria influence aggregate stability on ultramafic Ferralsols? A metagenomic approach in a tropical hotspot of biodiversity
Plant and Soil, 2020Co-Authors: Julien Demenois, Alexia Stokes, Luis Merino-martín, Nicolas Fernandez Nuñez, Fabian CarricondeAbstract:Understanding how soil aggregate stability (MWD) is influenced by microbial diversity and abundance can be crucial for ecological restoration in severely disturbed areas. We investigated the relationships between plant and soil microbial diversity and MWD of an ultramafic Ferralsol along a vegetational succession gradient in New Caledonia, where wildfires and extensive nickel mining have degraded the landscape. Five plant communities were studied. For each one, MWD, soil physicochemical parameters (e.g. soil organic carbon (SOC)), plant root traits and fungal abundance were measured. The diversity and structure of plant and microbial communities were respectively assessed via botanical inventories and a metagenomic approach. A generalized linear model (GLM) was used to assess the influence of diversity indexes on MWD. Constrained ordinations (CCA) were performed to assess the influence of communities’ structures on MWD. GLM highlighted the linkage between SOC and MWD but did not identify any significant influence of diversity indexes on MWD. CCA revealed a significant influence of communities’ structures, especially the abundance of saprotrophic fungi, on MWD. We showed that the structure, but not species richness and diversity of plants, soil fungi and bacteria influence aggregate stability on Ferralsols.
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Linkages between root traits, soil fungi and aggregate stability in tropical plant communities along a successional vegetation gradient
Plant and Soil, 2018Co-Authors: Julien Demenois, Freddy Rey, Thomas Ibanez, Alexia Stokes, Fabian CarricondeAbstract:Aims: Determining which abiotic and biotic factors influence soil aggregate stability (MWD) in tropical climates is often confounded by soil type, especially when large amounts of aluminium and iron oxides are present, such as in Ferralsols. We aimed at understanding the role of soil physical and chemical components, vegetation and fungal biomass influencing the aggregate stability of a Ferralsol along a successional gradient of vegetation in New Caledonia. Methods: Five plant communities, ranging from sedge dominated ecosystems to well-established mixed rainforest were studied. For each community, MWD, soil texture, soil organic carbon (SOC), iron and aluminium sesquioxides, root length density (RLD), specific root length (SRL), root mass density (RMD) and fungal biomass were measured. Results:The best prediction of MWD combined abiotic and biotic factors. Along the gradient, Fe increased MWD, while root traits, fungal abundance and SOC modified MWD. From the sedge-dominated community to Arillastrum forest, RMD and SOC increased MWD, while between Nothofagus and mixed rainforest, it was likely that floristic composition and fungal communities influenced MWD. Conclusion : Plant community, the intrinsic nature of Ferralsol and fungal abundance all modified MWD. However, the specific effect of microbial communities should be addressed through a metagenomics approach to elucidate microbial interactions with plant communities.
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Tropical plant communities modify soil aggregate stability along a successional vegetation gradient on a Ferralsol
Ecological Engineering, 2017Co-Authors: Julien Demenois, Freddy Rey, Fabian Carriconde, Alexia StokesAbstract:Soil aggregate stability is viewed as a promising indicator of the restoration status in eroded ecosystems, where the change in plant community composition through successional dynamics is a key driver of ecosystem restoration. In many tropical regions, ecological restoration is an important issue, but the relationship between different types of plant communities and soil aggregate stability is poorly understood. We examined how tropical plant communities modified soil aggregate stability along a successional vegetation gradient on a Ferralsol in New Caledonia. We identified five plant communities, ranging from an early (sedge dominated ecosystems) to a late successional stage (well-established, dense, mixed rainforest). Aggregate stability, total soil organic carbon (SOC) and iron and aluminium sesquioxides were measured in soil originating from each community. Results showed that aggregate stability of the Ferralsol was very high, even on eroded sites, likely due to the high levels of iron and aluminium sesquioxides also found. The levels of iron sesquioxides were particularly high (>10%), due partly to the frequency of wildfires in the region. Total SOC increased from sedgedominated communities (3.5%). Aggregate stability was modified by plant cover and community composition and increased from sparse, early successional vegetation to late successional dense, mixed rainforest. Our study showed that certain plant species have a positive impact on soil aggregate stability and should be considered for ecological restoration on Ferralsols. e.g., Costularia arundinacea, Garcinia amplexicaulis and Myodocarpus fraxinifolius. In conclusion, we suggest that vegetation dynamics should be taken into account when investigating changes in aggregate stability in a context of ecosystem restoration.