Dispersed information on water retention and availability in soils may be compiled in databases to generate pedotransfer functions. The objectives of this study were: to generate pedotransfer functions to estimate soil water retention based on easily measurable soil properties; to evaluate the efficiency of existing pedotransfer functions for different geographical regions for the estimation of water retention in soils of Rio Grande do Sul (RS); and to estimate plant-available water capacity based on soil particle-size distribution. Two databases were set up for soil properties, including water retention: one based on literature data (725 entries) and the other with soil data from an irrigation scheduling and management system (239 entries). From the literature database, pedotransfer functions were generated, nine pedofunctions available in the literature were evaluated and the plant-available water capacity was calculated. The coefficient of determination of some pedotransfer functions ranged from 0.56 to 0.66. Pedotransfer functions generated based on soils from other regions were not appropriate for estimating the water retention for RS soils. The plant-available water content varied with soil texture classes, from 0.089 kg kg-1 for the sand class to 0.191 kg kg-1 for the silty clay class. These variations were more related to sand and silt than to clay content. The soils with a greater silt/clay ratio, which were less weathered and with a greater quantity of smectite clay minerals, had high water retention and plant-available water capacity.<br>Informações dispersas sobre retenção e disponibilidade de água em solos podem ser agrupadas em bancos de dados para gerar funções de pedotransferência. Os objetivos do trabalho foram: gerar equações de pedotransferência para estimar a retenção de água a partir de atributos do solo de fácil obtenção; avaliar a eficiência de pedofunções existentes para várias regiões para a estimativa da retenção de água em alguns solos do RS; e estimar a disponibilidade de água em função da distribuição do tamanho das partículas dos solos. Dois bancos de dados com atributos do solo, incluindo retenção de água foram organizados: um a partir de dados da literatura (725 dados) e outro de solos de um sistema de monitoramento e manejo de irrigação (239 dados). Com o banco da literatura foram geradas funções de pedotransferência, avaliadas nove pedofunções disponíveis na literatura e calculado o teor de água disponível. As equações de pedotransferência geradas tiveram coeficientes de determinação entre 0,56 e 0,66. Equações de pedotransferência geradas com solos de outras regiões não foram adequadas para estimar a retenção de água de alguns solos do RS. O teor de água disponível variou em função da classe textural do solo, desde 0,089 kg kg-1 para a classe areia, a 0,191 kg kg-1 para a classe argilo siltosa. As variações foram mais dependentes das frações areia e silte do que da argila. Os solos com maior relação silte/argila, menos intemperizados e com maior quantidade de argilominerais do grupo das esmectitas, tiveram maior retenção e disponibilidade de água.

[ES]Los humedales son estructuras complejas capaces de transformar y/o eliminar compuestos dañinos, depurando las aguas eutrofizadas y/o contaminadas que fluyen a través de los mismos. Además de servir como filtro verde, tienen una importante influencia sobre la evolución de los recursos hídricos, la dinámica ecológica y las actividades económicas de las zonas donde se encuentren. En este proyecto se estudiaron una serie de procesos físicos y biogeoquímicos que controlan la evolución química de las aguas y de los sedimentos por procesos naturales y antrópicos en el humedal de Brujuelo. Para ello, se realizó una caracterización hidroquímica de las aguas superficiales del humedal midiendo parámetros fisicoquímicos in situ, y aplicando técnicas instrumentales tales como ICP-MS y cromatografía iónica. También se llevó a cabo una caracterización mineral de sus sedimentos mediante DRX y SEM. Los resultados obtenidos permitieron determinar las variables que controlan las transformaciones minerales que ocurren en ambientes lacustres de elevada salinidad y ricos en materia orgánica, caracterizar los ciclos geoquímicos implicados en este tipo de ambientes y evaluar el papel de algunos minerales en la atenuación natural de los compuestos contaminantes procedentes de distintas fuentes (Fe, Mn, Pb y otros elementos traza (ET) nocivos para el medio ambiente. PALABRAS CLAVE: HUMEDAL, CICLOS BIOGEOQUIMICOS, MINERAL, TRANSFORMACIONES MINERALES, ATENUACIÓN NATURAL DE CONTAMINANTES, MATERIA ORGANICA, HIDROGEOLOGÍA. | [EN]KEY WORDS: WETLAND, BIOGEOCHEMICAL CYCLES, MINERAL, MINERAL TRANSFORMATIONS, NATURAL ATTENUATION OF POLLUTANTS, ORGANIC MATTER. DESCRIPTION: Wetlands are complex structures capable of transforming and/or eliminating harmful compounds, purifying the eutrophized and/or contaminated waters that flow through them. In addition to serving as a green filter, they have an important influence on the evolution of water resources, ecological dynamics and economic activities in the areas where they are located. In this project, a series of physical and biogeochemical processes that control the chemical evolution of waters and sediments by natural and anthropic processes that converge in the Brujuelo wetland were studied. For this, a hydrochemical characterization of the surface waters of the wetland by measuring physicochemical parameters in situ, and applying instrumental techniques such as ICP-MS and ion chromatography. A mineral characterization of its sediments was also carried out by DRX and SEM. The results obtained allowed to determine the variables that control mineral transformations that occur in lake environments of high salinity and rich in organic matter, characterize the geochemical cycles involved in these types of environments and evaluate the role of some minerals in the natural attenuation of the compounds pollutants from different sources (Fe, Mn, Pb and other trace elements (TE) harmful to the environment

(ES)Los humedales son hábitats de gran valor ambiental a nivel local, regional e internacional. Su importancia radica en la gama amplia de servicios ecosistémicos que brinda a la humanidad y los problemas vinculados con su gestión y manejo. En España, estos hábitats han sido estudiados desde diferentes disciplinas a partir de la segunda mitad del siglo pasado, sin embargo, aún existen humedales sin caracterizar y, dado que no se puede cuidar lo que no sé conoce, es preciso abordar el estudio de la mayor cantidad de ellos. Uno de estos hábitats es el humedal de la Laguna del Tranco en Hornos, en la provincia de Jaén, que por sus particulares propiedades químicas, físicas y bióticas resulta atractivo para su análisis. El presente estudio propone abordar la caracterización del agua de la Laguna del Tranco, los sedimentos de esta, así como las interacciones agua-roca del humedal desde un marco físico, químico e hidrogeológico, el cual proporciona un enfoque útil para comprender la composición de las aguas y las dinámicas de transporte y transformación de los sedimentos. Para llevar a cabo esta caracterización se realizaron medidas in situ de parámetros fisicoquímicos del agua, se plantea el uso de técnicas de cromatografía iónica, espectrometría de masas con plasma acoplado inductivamente y determinación de isotopos estables para las aguas. En el caso de los sedimentos se usaron técnicas de difracción de rayos X y microscopia electrónica de barrido, para realizar la caracterización de los minerales y las interacciones agua-roca del humedal. Los resultados permitieron identificar las facies químicas del agua, su composición y origen; la composición y estructura mineral de los sedimentos, las variables, procesos y ciclos biogeoquímicos que controlan sus transformaciones. | (EN) Wetlands are habitats of great environmental value at the local, regional, and international levels. Its importance lies in the wide range of ecosystem services it provides to humanity and the problems related to its management and management. In Spain, these habitats have been studied from different disciplines since the second half of the last century, however, there are still uncharacterized wetlands and, given that what is unknown cannot be cared for, it is necessary to approach the study of the more of them. One of these habitats is the Laguna del Tranco wetland in Hornos, in the province of Jaén, which, due to its chemical, physical and biotic properties, is attractive for analysis. The present study proposes to approach the characterization of the water of Laguna del Tranco, its sediments, as well as the water-rock interactions of the wetland from a physical, chemical, and hydrogeological framework, which provides a useful approach to understand the composition of the waters and the dynamics of transport and transformation of sediments. To carry out this characterization, in situ measurements of physicochemical parameters of the water were carried out, the use of ion chromatography techniques, inductively coupled plasma mass spectrometry and determination of stable isotopes for water is proposed. In the case of the sediments, X-ray diffraction and scanning electron microscopy techniques were used to characterize the minerals and the water- rock interactions of the wetland. The results allowed to identify the chemical facies of the water, its composition and origin; the composition and mineral structure of the sediments, the variables, processes, and biogeochemical cycles that control their transformations.