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Geochemical dispersion and concentration of Pb and Zn in soils of the northern Midlands of IrelandKelly, Susan January 2000 (has links)
No description available.
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Exploring Physical and Chemical Trends in a Chronosequence of TechnosolsSmart, Kyle E. 15 July 2021 (has links)
No description available.
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Long-Term Effects of Rock Type, Weathering and Amendments on Southwest Virginia Mine SoilsNash, Whitney Laine 07 June 2012 (has links)
This study measured the effects of spoil type and amendments on Appalachian mine soil properties over time. The Controlled Overburden Placement Experiment was installed in 1982 in two parts, the Rock Mix (RM) Experiment compares mixes of sandstone (SS) and siltstone (SiS) spoils while the Surface Amendment (SA) Experiment compares a fertilized control (CON), sawdust (SD at 112 Mg ha⁻¹), topsoil (TSâ 15 cm), and biosolids (BS) at 22, 56, 112 & 224 Mg ha⁻¹. Both experiments were sampled in 2008 and compared with historical data. After 26 years, all RM treatments had higher silt+clay and decreased sand. Mine soil pH and electrical conductance (EC) were lower in high SS spoils and overall pH was lower and EC higher in surface layers. Fe-oxides increased over time and adversely affected extractable P. Exchangeable cations and total N increased in all treatments. Annual C-sequestration rates were 0.51 Mg ha⁻¹ for 1:1 SS:SiS and 0.32 Mg ha⁻¹ for SiS. In the SA experiment, extractable P and exchangeable cations increased over time in organically amended plots. The CON and TS sequestered C at 0.54 Mg ha⁻¹ and 0.87 Mg ha⁻¹ annually while higher BS and SD treatments lost C, but mobilized significant C into their subsoils. In the SA, an apparent C retention maximum of 30-35 Mg ha⁻¹ was noted. Overall, rock type and amendment effects were still evident after 26 years and the long-term benefits of organic amendments were reflected in sustained higher C, exchangeable cations, total N and P levels. / Master of Science
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Pedogenesis on the Sefton Coastal Dunes, NW EnglandMillington, Jennifer A. January 2010 (has links)
This work examines the use of pedo-properties to identify dune soil system responses to environmental change on the Sefton coast, based on the development of conceptual pedogenic models. Previous environmental change and shoreline dynamics are determined through O.S. maps and aerial photographs, while present day processes are investigated through a dune-toe photographic survey and seasonal monitoring by fixed point photography. Topsoil (0-5 cm) physico-chemical characteristics are presented in a series of baseline GIS maps, displaying spatial pedo-property variation across the dune landscape. Combined with vegetation data, topsoil analysis identifies 10 distinct pedo-environments. Physico-chemical characteristics of associated National Soil Resources Institute (NSRI) soil profile classifications and an exposed stratigraphic section are presented graphically in a proposed sequence of development. Topsoil and soil profile samples are analysed for soil pH, soil organic matter (SOM) content, particle size, geochemical composition and mineral magnetism. Significant differences (p <0.05) are apparent for the suite of topsoil characteristics collated, indicating discrete dune environments are influenced by specific soil properties. Distinct down-profile variations in soil characteristics are also apparent between dune environments, highlighting pedological dynamism. Multivariate Factor analysis groups bare sand and mobile dune communities into ‘frontal dunes’ and fixed dune community, pasture, scrub, deciduous woodland and coniferous plantations into ‘hind dunes’, separating these topsoil environments from heath and slack communities. Factor analysis also identifies linkages between pedo-characteristics within soil profile horizons, suggesting pedogenesis on the Sefton dunes initiates as raw sand, progressing to sand-pararendzinas through leaching of nutrients. Desalinization and decalcification processes lead to brown earth development, followed by increased acidicification, subsequently, resulting in micro-podzol formation. Groundwater gley soils are associated with dune slacks, where drainage is inhibited and anaerobic conditions prevail. Analysis of buried soils suggests such pedo-environment formations are cyclic, responding to phases of shoreline regression/transgression, dune activity and stabilization. Conceptual models are designed to graphically demonstrate pedogenesis under both erosion and deposition regimes on the Sefton coast. Regression equations and correlation coefficients between pedo-properties and distance from mean high water are used as a proxy for soil age, which represent lateral soil maturity from the unstable frontal dunes to the stable hind dunes inland. The models simulate formation and process of the full array of soil properties, accounting for geomorphological impacts and anthropogenic influences. This has great implications for dune managers by raising awareness of pedogenesis as an integral part of nature and associated habitats, which could be incorporated in future shoreline management plans (SMPs).
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Aspectos pedológicos relacionados à irrigação em tabuleiros costeiros (Platô de Neópolis-SE)Luz, Lúcia Raquel Queiroz Pereira da [UNESP] 13 December 2005 (has links) (PDF)
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luz_lrqp_dr_botfca.pdf: 1562344 bytes, checksum: 1549f653cebb07c521832df2df4e1837 (MD5) / Em extensas áreas planas, processos pedogenéticos relacionados às condições de drenagem, que em amplos tabuleiros ocorrem de maneira fechada, concentrando o excesso de água em pequenas depressões, atuam sobre os solos modificando suas propriedades. Estudar aspectos pedológicos relacionados à agricultura irrigada, buscando relacionar aspectos edáficos com a dinâmica da água nos perfis e ao longo do relevo, foi o objetivo deste trabalho. Foram descritos e amostrados perfis nos terços superior, médio e inferior em área com declividade média de 1,3%, cultivada com citros sob irrigação localizada e em outra área adjacente sob as mesmas condições de relevo, mantida em pousio há mais de 10 anos. Foram feitas análises físicas, químicas, mineralógicas e micromorfológicas. O estudo concluiu que as diferenças entre os perfis refletem as condições de drenagem impostas pelo relevo e que as diferenças entre os horizontes dos perfis, principalmente quanto à granulometria e estrutura, proporcionam condições diferenciadas de retenção e infiltração e água no solo, favorecendo o fluxo lateral e o acúmulo de água em camadas mais profundas das áreas mais baixas da encosta, influenciando processos pedogenéticos relacionados à hidrólise. Concluiu ainda que para a preservação ambiental e a sustentabilidade da citricultura faz-se necessário buscar soluções para possibilitar melhor eficiência de uso da água, considerando a variabilidade dos solos e as condições impostas pelo relevo. / The aim of this work was studding pedologic aspect related to irrigated agriculture in plan surfaces, where the drainage is closed, concentrating the excess of water in small depths, act on the soils modifying its prorieties. Soil profiles were described and analyzed on the superior, medium and lower positions of the hill in a flat area (average of declivity 1,3%) cultivated with citric plants by micro sprinkler in comparison to a neighbor area, with de same relief conditions, kept without cultivation by a superior time ten years. Physical, Chemical, mineralogical and micromorphological analysis were done, relating these characteristics to the pedogenetics procedures involved on those soil formations. The study concluded that differences between the profiles of the areas with the irrigated cultivation and non cultivated, based on the morphologic, physical, chemical and micromorphological proves the conditions of drainage imposed by the positioning of the soil on the landscape and that the adding of water have provided conditions of flooding on deep layers of the soil accelerating pedogenetics procedures. For the environment preservation and the sustainability of the fruit culture in similar areas to the studied is necessary to search solutions to provide efficiency of the use of the water added to the soil by irrigation, considering the variability of the soils and the imposed conditions by the relief in relation to natural draying.
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EvoluÃÃo PedogenÃtica em Duas Vertentes do MaciÃo de Baturità - CE / Evolution pedogenetic in two parts of the Mass Baturità - CEWesley Rocha Barbosa 03 February 2008 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Dada a importÃncia das condiÃÃes climÃticas para o desenvolvimento dos solos, aliado a ocorrÃncia de variaÃÃes de umidade e temperatura em Ãreas muito prÃximas, este trabalho teve como objetivo identificar e caracterizar os solos altimontanos nas vertentes Ãmida (VU) e seca (VS) do MaciÃo de BaturitÃ, considerado, em parte, um enclave Ãmido inserido na regiÃo semi-Ãrida do Estado do CearÃ. Analisaram-se 08 (oito) perfis, sendo 04 (quatro) em cada vertente, a partir da descriÃÃo morfolÃgica, atributos fÃsicos, quÃmicos e micromorfolÃgicos necessÃrias para o entendimento dos principais processos pedogenÃticos atuantes. Foram identificadas as seguintes classes de solos: Cambissolo HÃplico (P1 e P4) e Argissolo Amarelo (P3 e P4) na vertente Ãmida e Argissolo Vermelho (P1), Luvissolo CrÃmico (P2) e Cambissolo HÃplico (P3 e P4) na vertente seca. O lado Ãmido apresentou caracterÃsticas de um maior potencial de percolaÃÃo da Ãgua que ocasionou maiores perdas de bases por lixiviaÃÃo e altos conteÃdos de Al trocÃvel, cujos valores mÃdios foram de S = 2,2 cmolc.kg e Al = 4,1 cmolc.kg e, consequentemente, reaÃÃo fortemente Ãcida (pH mÃdio = 5,1). A vertente seca apresentou caracterÃstica de ambiente mais propÃcio a oxidaÃÃo, causada pela maior aeraÃÃo do pedoambiente, denunciado pela cor mais avermelhada. Confrontando os dados da VU com os da VS, a menor espessura do solum dos pedons desta Ãltima, assim como, menor concentraÃÃo de argila nos horizontes B (306 à 343 g.kgÂ) e elevados teores de cÃtions trocÃveis (S = 12,8 cmolc.kgÂ), alÃm de outros atributos fÃsicos, quÃmicos e morfolÃgicos, indicam o menor grau de evoluÃÃo dos solos na VS, confirmando o contraste entre os solos localizados em lados opostos do MaciÃo. / Given the importance of the climate conditions for the development of soils, together with the occurrence of moisture and temperature variations in very near areas, The purpose of this work was to identify and characterize the soils into a sequence in the moist and dry slopes of MaciÃo de BaturitÃ, which is considered a moist enclave inserted in the semi-arid region of Cearà State. It was analyzed eight profiles, 04 out of them in each slope, from the morphological description, physical, chemical and micromorphological attributes on necessaries for the understanding of the main pedogenetic processes acting. It was identified the following soil classes: Haplic Cambisoil (P1 and P4) and Yellow Argisoil (P3 and P4) in the moist slope and Red Argisoil (P1), Chronis Luvisoil (P2) and Haplic Cambisoil (P3 and P4) in the dry slope. The moist side showed characteristics of a large potential of water percolation that caused greater loses of bases by lixiviation and high contents of exchangeable A1, whose values were S = 2,2 cmolc.kg and Al = 4,1 cmolc.kg and, consequently, strongly acid reaction (middle pH = 5,1). The dry slope showed a characteristic of an environment favorable for oxidation caused by greater aeration of the pedoenvironment, denounced by the reddish color. Comparing the moist slopeâs data with the dry slopeâs, the smallest thickness of the solum of the dry slopeâs pedons, as well as, lower concentration of clay in the horizons B (306 to 343 g.kgÂ) and high contents of exchangeable cations (S = 12,8 cmolc.kgÂ), besides other physical, chemical and morphological attributes, indicate the lower degree of evolution of soils in the dry slope, confirming the contrast among the soils located in opposite sides of MaciÃo.
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Analyse des mécanismes du lessivage des argiles dans les sols par des approches expérimentales / Analysis of clay lessivage mechanisms in soils by experimental approachesVan Den Bogaert, Romain 11 March 2015 (has links)
Parmi les processus pédogénétiques, le lessivage des argiles dans les sols est un processus très répandu qui consiste en un transfert de particules, d’un horizon supérieur éluvié vers un horizon illuvié. Néanmoins, un certain nombre de lacunes persiste dans la compréhension de ce processus. Nous avons donc étudié : les processus d’écoulement de l’eau dans la porosité active, l’effet des cycles pluie - interpluie sur la rétention des particules, et les conséquences des perturbations physico-chimiques de la solution du sol sur la stabilité en suspension des particules de sols. Pour aborder ces différents points, nous avons fait le choix d’une approche réductionniste de laboratoire couplée à des méthodes analytiques modernes, souvent peu usitées en sciences du sol. Comme matériaux modèle, des horizons E de luvisol non remanié et des particules argileuses naturelles extraites de ces mêmes horizons ont été utilisés. Pour la première fois nous avons pu visualiser que les écoulements macroporeux préférentiels s’effectuent sous forme de ruisselets. Notre travail permet en outre, une première avancée vers l’estimation de la surface de contact eau – sol. Nous montrons que la rétention des particules s’effectue dans une zone de matrice à proximité macropores actifs, zone plus ou moins importante selon la durée de l’interpluie. Nous avons enfin montré que les variations de la concentration en calcium et du pH de la solution, consécutives à l’infiltration de l’eau de pluie dans la porosité, provoquent une évolution de l’arrangement des particules en suspension sur une échelle de temps correspondant à la durée d’un évènement pluvieux / Clay translocation is a widespread process of particle transfer from a surface eluviated horizon to a deeper illuviated horizon. Nevertheless, a number of gaps persist in understanding this process. We therefore investigated: the water flow processes in the active porosity, the effect of rain-interrain cycles on the retention of particles, and the consequences of physical and chemical disturbances of the soil solution on the stability of soil particles in suspension. To address these issues, we have made the choice of a laboratory reductionist approach coupled with modern analytical methods, poorly used in soil science. As a model materials, we used undisturbed luvisol E horizons and natural clay particles extracted from these horizons. We show experimentaly for the first time that macroporous preferential flow consist in rivulets. Our work also provides a first step towards estimating the water-soil specific surface area. We show that particle retention occurs in the matrix close to active macropores, the thickness of the concern matrix being a function of the interrain duration. Finally we have shown that the variations of the calcium concentration and pH of the soil solution, subsequent to the infiltration of rain water into the pores, cause a change in the arrangement of the particles in the soil suspension on a timescale corresponding to the duration of a rainfall event
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Pedogenesis & Carbon Dynamics Across a Lithosequence Under Ponderosa PineHeckman, Katherine Ann January 2010 (has links)
Three studies were completed to investigate the influence of mineral assemblage on soil organic carbon (SOC) cycling and pedogenesis in forest soils. Two studies utilized a lithosequence of four parent materials (rhyolite, granite, basalt, limestone/volcanic cinders) under Pinus ponderosa, to explicitly quantify the contribution of parent material mineral assemblage to the character of the resulting soil. The first study explored variation in pedogenesis and elemental mass loss as a product of parent material through a combination of quantitative X-ray diffraction and elemental mass balance. Results indicated significant differences in degree of soil development, profile characteristics, and mass flux according to parent material.The second study utilized the same lithosequence of soils, but focused on organic C cycling. This study explored variation in SOC content among soils of differing mineralogy and correlations among soil physiochemical variables, SOC content, soil microbial community composition and respiration rates. Metal-humus complex and Fe-oxyhydroxide content emerged as important predictors of SOC dynamics across all parent materials, showing significant correlation with both SOC content and bacterial community composition. Results indicated that within a specific ecosystem, SOC dynamics and microbial community vary predictably with soil physicochemical variables directly related to mineralogical differences among soil parent materials.The third study focused specifically on the influence of goethite and gibbsite on dissolved organic matter characteristics and microbial communities which utilize DOM as a growth substrate. Iron and aluminum oxides were selected for this study due to their wide spread occurrence in soils and their abundance of reactive surface area, qualities which enable them to have a significant effect on SOC transported through forest soils. Results indicated that exposure to goethite and gibbsite surfaces induces significant differences in DOM quality, including changes in thermal properties, molecular structure, and concentrations of P and N. Investigation of the decomposer communities indicated that exposure to goethite and gibbsite surfaces caused significant differences in microbial community structure.These investigations emphasize the important role of mineral assemblage in shaping soil characteristics and regulating the cycling of C in soils, from the molecular scale to the pedon scale.
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Subaqueous soils of the Brazilian seagrass meadows: biogeochemistry, genesis, and classification / Solos subaquáticos das pradarias marinhas do Brasil: biogeoquímica, gênese e classificaçãoNobrega, Gabriel Nuto 27 July 2017 (has links)
Seagrass meadows, or submerged aquatic vegetation, constitute an ecosystem with great importance to the coastal zone, and may be characterized as the most productive ecosystem on Earth. In addition to the provision of habitat for a wide variety of species, protection of the coastal zone and production of organic matter base for the marine trophic web, these environments have been recognized for their great capacity to store organic carbon in their soils and are, therefore, a priority area for the mitigation of increased carbon in the atmosphere. In spite of the great importance of these areas, there is little information about the soils of these ecosystems, mainly using an approach based on the genesis of its soils. Thus, this thesis covers 4 chapters aiming to: (i) evaluate changes in the characteristics of seagrass meadows publications in the last 50 years, identify knowledge gaps and priorities for future studies; (ii) to discuss the paradoxical lack of information on Brazilian seagrass meadows soils, stimulate studies to understand their characteristics and contribute to the correct inclusion of seagrass meadows soils in the Brazilian System for Soil Classification; (iii) characterize and investigate soils of seagrass meadows along the Brazilian coast, in order to understand the pedogenetic processes within these soils; and (iv) identify variations in the biogeochemical processes related to the dynamics of Fe, Mn and S along the Brazilian coast, aiming to provide an improved basis for the understanding of this ecosystem and subsidies for the use and protection policies of these coastal areas. / As pradarias marinhas (seagrasses), ou vegetação aquática submersa, constituem um ecossistema de grande importância para a zona costeira, caracterizando-se como o ecossistema mais produtivo da Terra. Além de fornecer habitat para uma grande variedade de espécies, favorecer a estabilidade costeira e produzir matéria orgânica base para a teia trófica marinha, estes ambientes têm sido reconhecidos pela grande capacidade de armazenar carbono orgânico em seus solos e são, portanto, prioritários para as medidas de mitigação do aumento de carbono na atmosfera. Apesar da grande importância desse ecossitema, há pouca informação a respeito dos solos onde estes ecossistemas estão inseridos, principalmente utilizando uma abordagem baseada na gênese dos solos. Esta tese contempla 4 capítulos cujos objetivos visam avaliar as mudanças nas características das publicações sobre pradarias marinhas nos últimos 50 anos, identificando lacunas de conhecimentos e prioridades para estudos futuros; discutir a paradoxal ausência de informação sobre os solos das pradarias marinhas do Brasil, estimulando estudos para o entendimento de suas características e contribuindo para a correta inclusão de solos de pradarias marinhas no Sistema Brasileiro de Classificação de solos; caracterizar e investigar os solos das pradarias marinhas ao longo da costa brasileira, com vistas a entender os processos pedogenéticos atuantes nestes solos; e Identificar variações nos processos biogeoquímicos relacionados à dinâmica de Fe, Mn e S ao longo da costa brasileira, com a finalidade de fornecer base para o entendimento deste ecossistema e subsídios para as políticas de proteção e de uso destas áreas costeiras.
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Processos pedogenéticos e biogeoquímica de Fe e S em solos de manguezais / Pedogenic processes and biogeochemistry of Fe and S in mangrove soilsFerreira, Tiago Osorio 21 February 2006 (has links)
Em função de seu importante papel funcional e de sua posição de transição entre o ambiente marinho e terrestre, os ecossistemas estuarinos vêm sendo objeto de estudo das mais diversas áreas do conhecimento. Entretanto, poucos são os estudos destinados ao entendimento da biogeoquímica e gênese de seus solos. Os compostos de ferro e enxofre são tidos como de importância chave para os ciclos biogeoquímicos ativos nestes ambientes, principalmente pelo fato de a redução bacteriana do sulfato (RBS) ser considerada como a forma de respiração preponderante nestes locais. O ciclo biogeoquímico destes elementos se encontra, entretanto, governado pelas variações físico-químicas do meio devido a variações incessantes em função da freqüência de inundação pelas marés, das diferentes estações climáticas e da atividade da fauna e da flora presentes nestes ambientes. Diante do escasso número de informações sobre estes solos pretende-se, em um estudo biogeoquímico detalhado dos solos de mangue do Estado de São Paulo, gerar informações adicionais sobre a gênese destes solos e avaliar os efeitos das variações sazonais, da atividade biológica (plantas e macro-fauna) e das distintas posições fisiográficas dentro dos manguezais, sobre a biogeoquímica do Fe e S. Para isso, foram realizadas análises morfológicas, químicas, mineralógicas (DRX e MEV), determinações na água intersticial (pH, salinidade, concentrações de Mn2+, Fe2+, HS-, SO4 2-e Cl-) e na fase sólida (COT, Fe total, S total, Mn total, AVS, C biomassa microbiana, densidade de raízes vivas e mortas, porcentagem de areia e extração seqüencial das diferentes formas de Fe) em diferentes perfis sob vegetação de mangue do Estado de São Paulo (Guarujá e Cananéia). Com base nas evidências obtidas neste estudo fica evidente a ação de processos pedogenéticos nos substratos de mangue (adição de matéria orgânica, translocação de Fe2+ e de partículas minerais e a transformação de elementos como Fe e S) os quais devem, portanto, ser denominados, entendidos e estudados como solos e não como sedimentos. Os resultados sugerem a oxidação das frações pirítica e AVS pela ação do sistema radicular das plantas e pela atividade da macro-fauna, principalmente caranguejos, evidenciando ainda a presença de um ciclo sazonal na biogeoquímica do Fe e S o qual se mostra, em grande parte, governado pela ação das plantas e da macro-fauna. Foram encontradas diferenças drásticas entre as condições geoquímicas da água intersticial dos solos e sedimentos de mangue estudados, sendo estas devidas a um maior dinamismo dos processos biogeoquímicos atuantes nos solos, ocasionado pelo efeito das plantas (oxidação, liberação de exudatos pelas raízes). Os resultados obtidos apontam que a participação e a intensidade de cada um dos processos ligados à decomposição da matéria orgânica nos solos de mangue podem variar em função das distintas posições fisiográficas, devido a seus efeitos sobre a freqüência e duração de inundação e composição granulométrica dos solos. Os resultados indicam também, que a ocorrência ou a dominância de um processo sobre os demais afeta de forma significativa a composição das fases sólida e líquida dos solos de mangue, no que se refere ao Fe e S. / Due to the important functional role of mangrove forest communities and their transitional position between marine and terrestrial environments, these ecosystems have been the object of study by a variety of scientific disciplines; however, there are only a few published studies on the genesis and biogeochemistry of its soils. Iron and sulfur compounds play a key role on the active biogeochemical cycles in these environments, mainly because sulfate reduction is considered the preponderant respiration process in these sites. The biogeochemical cycles of these elements are, however, ruled by physicochemical variations constantly generated by tide flooding, different climatic seasons and fauna and flora activity. Considering the scarce information about these soils, a detailed biogeochemical study of mangrove sites located in the State of São Paulo was undertaken to generate additional information on the genesis of these soils and also to evaluate the effects of seasonal variations, biological activity (plants and macrofauna) and physiographic positions on Fe and S biogeochemistry. Morphological, chemical and mineralogical data (XRD and SEM) were examined for evidence of pedogenic processes; interstitial water (pH, salinity, concentrations of Mn2+, Fe2+, HS-, SO4 2-e Cl-) and solid phase (TOC, total Fe, total S, total Mn, AVS, microbial biomass C, density of living and dead roots, sand percentage and sequential extraction of Fe) analysis were undertaken in different soil profiles under mangrove vegetation from São Paulo State (Guarujá and Cananéia) to asses Fe and S biogeochemistry. The evidences presented in this study indicate that pedogenic processes (addition of organic material; translocation of Fe2+ and mineral particles; transformation of elements such as Fe and S) have occurred in mangrove substrates and that these substrates are more properly referred to, understood and studied as soils and not sediments. Results also evidence that pyrite and AVS oxidation is taking place in response to plants and macro-fauna activity and that the seasonal cycle of Fe and S biogeochemistry is mostly ruled by plants and macro-fauna. Results indicate important differences between physicochemical conditions of the pore water in the vegetated (soils) and non-vegetated (sediment) zones, which are related to the faster dynamics of the biogeochemical soil processes caused by the effect of plants (oxidation, liberation of the exudates by the roots). Our data also show that the contribution and intensity of each process coupled to organic matter mineralization in mangrove soils may vary significantly between the distinct physiographic positions. These variations are generated by physiographic positions effects on frequency and duration of tidal flooding and grain size composition of soils. In this context, the occurrence, or dominance, of one process over the others, affects, in a significant way, pore water and solid phases chemistry.
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