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This article provides personal and professional assessments from disciples, colleagues and friends of Jaume Porta Casanellas (Barcelona, 1944; Lleida, 2023), a prominent soil scientist. He began his agricultural engineering studies at the Polytechnic University of Madrid (UPM) where he met Marta López-Acevedo, his wife and outstanding collaborator. At UPM, he started his early work in soil science under the guidance of Professor Carlos Roquero who became his mentor and friend. Jaume Porta was a dedicated, passionate soil scientist who engaged extensively in teaching and research in Soil Science, while also excelling as a manager. He emerged as a leader due to his initiatives in promoting Soil Science in Catalonia and Spain, and for his forward-thinking vision, evident in his decisions as Rector of the University of Lleida, which have significantly contributed to the city's development. From the beginning, he advocated for detailed (1:25,000) soil mapping of Catalonia to enhance territorial planning and agricultural progress. His primary research focus was on salt-affected soils and soils with gypsum, alongside soil erosion and conservation. Porta devoted a lot of effort to improve soil field descriptions with his Agenda de campo. He played a key role in standardizing soil analytical methods, establishing large series laboratories in Spain, notably the LAF in Sidamon (Lleida), and aligning Spanish soil labs with the international GLOSOLAN network. As president of the SECS, he energized activities and encouraged member participation. His educational publications, mainly his comprehensive textbook Edafología, are considered fundamental in Soil Science across Spanish-speaking countries, as is the Multilingual Dictionary of Soil Science, representing the pinnacle of his efforts to rigorously disseminate soil science concepts and terms in Spanish, Catalan, Galician, and Portuguese. He contributed significantly to international Soil Science courses in Mexico and played a key role in establishing the JADE postgraduate training program. He facilitated the creation and international visibility of the Spanish Journal of Soil Science. Additionally, he advocated for the establishment of the Soil Sciences Documentation Centre (Ce.SECS) to preserve historical publications and the legacy of soil scientists. Jaume Porta's enduring impact, both professionally and personally, will be felt for years to come. [ABSTRACT FROM AUTHOR]

A field experiment was conducted on the Andalusian coast (Granada, Southern Spain) to study the time course of nutrient release into the soil after the addition of bagged pruning waste from subtropical orchard trees (avocado, cherimoya, and mango) and urban garden waste over three two-year periods. N, P, and K concentrations were greater in the garden waste, whilst avocado and cherimoya pruning waste registered the highest values for Mg. In general, micronutrient contents were low in all waste, especially Cu. Macronutrient release followed a three-phase dynamic: fast initial release, intermediate stabilization, and final increase. Garden waste showed a similar time course in all three trees and released greater concentrations of K and P. The annual decomposition rate factor k was negative for N and Ca in the avocado tree, indicating strong biological activity in this plot. Avocado, cherimoya, and garden waste showed a good microbial degradation, improving soil quality by increasing carbon and nitrogen contents as well as soil microbial activity. As for the mango tree, its special microclimatic conditions appeared to favor waste photodegradation, thus eliminating nutrients that were not incorporated into the soil. Soil enzymatic activities increased in the avocado and cherimoya trees with the addition of all waste. In the mango tree, only an increase in urease was detected after the addition of garden waste. Our results suggest that the time course of organic waste in different subtropical trees grown on similar soils is significantly conditioned by the microclimatic characteristics. [ABSTRACT FROM AUTHOR]

The geochemistry and microbiology of a uranium-contaminated subsurface environment that had undergone two season of acetate addition to stimulate microbial U(VI) reduction is examined. The substantial microbial and geochemical heterogeneity demonstrates that attempts should be made to deliver acetate in a more uniform manner and that closely spaced sampling intervals, horizontally and vertically in both sediment and groundwater are necessary to obtain a more in-depth knowledge of microbial processes.

A study is conducted to demonstrate the specification of solid-phase uranium in uranium-contaminated subsurface sediments undergoing uranium bioremediation. The findings indicate that although microbial reduction of soluble U(VI) readily immobilized uranium as U(IV), a substantial portion of the U(VI) in the aquifer is strongly associated with the sediments and not microbially reducible.

Vanadium can be an important contaminant in groundwaters impacted by mining activities. A study conducted reveals that G. metallireducens can grow through vanadium respiration and that stimulating the activity of Geobacteraceae can be an effective strategy for in situ immobilization of vanadium in contaminated subsurface environments.

Research reveals that in situ bioremediation of uranium-contaminated groundwater can be accomplished by maintaining long-term activity of Geobacter species. Data show that addition of acetate to the groundwater stimulates the growth of Geobacter species, which coupled with their long-term growth remove uranium from the groundwater in situ.

Salinity is the major environmental factor limiting crop production. Alfalfa is a legume with high nutritional value that establishes a symbiosis relation with Ensifer meliloti . Under saline conditions the alfalfa yield decreases and this symbiosis is affected. The aim of this work is to study the effect of the co-inoculation of alfalfa plants with Halomonas maura (a moderately halophile bacterium) and E. meliloti in saline soils to improve their productivity and growth under greenhouse and field conditions. Alfalfa plants were grown in Leonard jar under greenhouse conditions, using a N-free mineral solution to mimic the conditions of an Orthic Solonchak. Then alfalfa plants were grown in the field in the same soil type. Seeds were inoculated with E. meliloti , H. maura , co-inoculated with E. meliloti and H. Maura , or non-inoculated as a control in both experiments. In greenhouse experiments the co-inoculation of alfalfa plants increased significantly the shoot dry weight (0.64 ± 0.02 vs . 0.79 ± 0.02), the leghaemoglobin content (10.17 ± 0.03 vs . 11.25 ± 0.06) and water potential (−3.12 ± 0.02 vs . −2.79 ± 0.02) compared with the single inoculation with E. meliloti . In the field experiments, biomass of co-inoculated plants clearly outyielded those of plants inoculated with any inoculant. The co-inoculation of H. maura and E. meliloti enhances alfalfa productivity in saline soils, thus contributing to the agricultural exploitation of low productive areas. H. maura and E. meliloti could be considered in formulation of bioinoculants to contribute in the reduction of the overuse of chemical fertilizers and their environmental impacts. [ABSTRACT FROM AUTHOR]