Repositori Obert UdL
The institutional repository collects, manages, disseminates and preserves publications in open access derived from the academic and research activity of the University of Lleida.
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Open Access
Short-term thinning effects on saprotrophic and ectomycorrhizal soil fungal communities in a Pinus halepensis common garden
(Springer Science and Business Media Deutschland GmbH, 2025) Centenaro, Giada; Miguel Magaña, Sergio de; Voltas Velasco, Jordi; Bonet Lledos, José Antonio; Alday, Josu G.; Dashevskaya, Svetlana
Background and aim: Soil fungal communities can vary in their abundance and diversity between host tree species, but also between genotypes within the same host tree species. However, there are conflicting results on the role of host tree genetics in shaping soil fungal communities and how silvicultural treatments can influence their dynamics. Methods: We investigated whether genetic variation among 20 populations representing five ecotypes of Pinus halepensis, the most widespread tree species in the Mediterranean basin, affects their soil fungal community, before and after a thinning treatment. Seedlings from these 20 populations were planted in 1996 in a common garden experiment (eastern Spain) under uniform climatic and soil conditions. In October 2019, a 50% thinning treatment was carried out and soil samples were collected immediately before and one year after thinning. Results: Before thinning, no significant differences in soil fungal composition were observed between ecotypes. However, saprotrophic richness increased significantly in three ecotypes and saprotrophic diversity in one ecotype one year after thinning. Conversely, the ectomycorrhizal fungal community diversity and composition of the five ecotypes showed non-significant changes following thinning. Conclusion: Our results suggest that genetic differentiation in the host tree plays a minor role in shaping the ectomycorrhizal and saprotrophic communities of Mediterranean Aleppo pine forests. Furthermore, the contrasting response of the ectomycorrhizal and saprotrophic communities to thinning treatment highlights the resilience of ectomycorrhizal communities to short-term disturbances such as thinning, while emphasizing the ability of the saprotrophic communities to exploit newly available resources.
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Open Access
AI and data analytics in the dairy farms: a scoping review
(MDPI, 2025) Palma, Osvaldo; Pla Aragonés, Lluís Miquel; Mac Cawley, Alejandro; Albornoz, Víctor M.
The strong growth of the world population will cause a major increase in demand for bovine milk, making it necessary to use various technologies to increase milk production efficiently. Some technologies that can contribute to solving part of this problem are those related to data analytics tools, big data, and sensor development. It is timely to review modern technologies and data analytics methods for milk predictions in view of supporting decision-making in dairy farms. To this end, a scoping review was carried out, which resulted in 151 articles of interest. Among the most important results, we found that (i) the identified studies are relatively recent with an average publication time of 5.95 years; (ii) the scope of the selected studies is mostly concentrated on milk and prediction (29%), early detection of lameness (26%), and timely detection of mastitis (13%); (iii) the type of analysis is mostly predictive (87%), and prescriptive is barely present (3%); (iv) the types of input data used in the studies are preferably historical (70%), and real-time data (25%) are used less frequently; (v) we found that the method of artificial neural networks (47%) and the convolutional neural networks (24%) are the most used for the studies regarding bovine milk output predictions. In the selected studies, the artificial neural network methods have considerable accuracy, recall, precision, and F1 Scores on average but with high ranges and standard deviations. (vi) Simulation tools are scarcely used, being present in 4% of cases. In the treatment of variability, the models reviewed are mostly deterministic (77%), and the stochastic models (5%) are considered in a small number of cases. Based on our analysis, we conclude that future research on decision-making tools will benefit from the advantages of artificial neural networks in data analytics combined with optimization–simulation methods.
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Open Access
Soil carbon, aggregation and crop residue dynamics under different tillage and nitrogen fertilization strategies in rainfed Mediterranean conditions
(Elsevier, 2025) Álvaro-Fuentes, Jorge; Cantero-Martínez, Carlos; Alonso-Ayuso, María; Gómez, Fernando; Ramos Martín, Ma. C. (Ma. Concepción)
n rainfed Mediterranean croplands, the interactive effects of fertilization and tillage types on soil aggregation and soil organic carbon (SOC) have been rarely studied. The objective of this study was to assess the interactive effects of tillage and nitrogen (N) fertilization strategies on different soil and crop properties in a long-term rainfed experiment established in semiarid NE Spain in 2010. During two cropping seasons (2020–2021 and 2021–2022) the following variables were assessed: SOC, particulate organic matter C (POM-C) and mineral-associated organic matter C (Min-C) contents in the 0–5, 5–10 and 10–30 cm depths; soil aggregate stability in the topsoil (0–5 cm); crop yield; and crop residue dynamics (crop residue biomass and the percent residue cover). Two tillage treatments were compared: conventional tillage (CT) and no-tillage (NT), and five N fertilization strategies: unfertilized, medium and high N rates of mineral fertilizer, and medium and high N rates of organic fertilizer. In both cropping seasons, the crop yield, crop residue biomass and percent residue cover were greater in NT compared with CT (2148 and 1319 kg ha −1 crop residue biomass and 72.0 and 49.7 % residue cover for NT and CT, respectively). Regarding N fertilization, crop yields tended to be greater in the organic fertilizer than in the mineral fertilization treatments (1600 vs 1168 kg ha−1, respectively). Differences between N fertilization treatments were more marked in the residue biomass parameter than in the percent residue cover. The SOC, POM-C and Min-C contents decreased in the next order across soil depths: 0–5 > 5–10 > 10–30. The greatest soil C values were observed in the treatments with the greatest N rate of organic fertilizer. The soil aggregate stability in the topsoil (0–5 cm) increased under NT and the application of organic fertilizers. This study has demonstrated that in rainfed semiarid conditions, long-term NT adoption and the use of organic fertilizers are promising strategies for enhancing SOC buildup and the formation of stable aggregates in the topsoil.
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Open Access
Drought-induced die-off triggers species composition shift at warmer and drier edges of climate gradient in Pinus sylvestris forests of Catalonia (NE Spain)
(Springer Science and Business Media Deutschland GmbH, 2025) Chowdhury, Faqrul Islam; Espelta, Josep Maria; Margalef-Marrase, Jordi; Jaime, Luciana; Lloret, Francisco
Climate change is increasing the frequency and intensity of drought episodes, with raising forest die-off events globally. Impacts of drought on tree growth and mortality have been extensively investigated, but studies on regeneration after these episodes and their consequences for tree diversity and potential plant composition shifts are still scarce, especially analysing climate gradients. We analyse the impact of drought-induced die-offs on woody plant diversity in Pinus sylvestris forests in Catalonia (NE Spain), considering local temperature and precipitation effects. We compared plots affected by die-off to non-affected ones, surveying tree layers in 2013, 2017, and 2022, and tree recruits in 2022. Die-off plots showed greater richness and diversity in tree layer after 5 and 10 years of die-off, particularly in drier sites, while higher evenness was observed in warmer sites. Such pattern indicated a vegetation shift towards a Mediterranean-type forest, with increasing ingrowths of Quercus, Acer, Prunus, and other broadleaf trees which incorporated to tree layer, potentially replacing dead P. sylvestris. In die-off plots, species richness and evenness of larger recruits were 36% and 42% higher, respectively, than in non-affected ones. Species in tree layer and recruiting communities showed a 29% higher similarity in die-off plots than in non-affected ones, supporting that die-off provide better opportunities for recruitment by incorporation into the tree canopy and successful establishment of new recruits. These results indicate that drought-induced die-off is triggering forests transition towards a more adapted plant composition to climate change concurrent with ongoing local climate conditions.
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Open Access
Diplodia tip blight (Diplodia sapinea) and site conditions shape Scots pine (Pinus sylvestris) endophytic mycobiome
(Elsevier, 2025) Brodde, Laura; Miñana-Posada, Silvia; Tudoran, Amelia; Angel Redondo, Miguel; Elfstrand, Malin; Oliva Palau, Jonàs; Stenlid, Jan
Diplodia sapinea (Fr.) Fuckelis is an opportunistic pathogen of Scots pine (Pinus sylvestris (L.) that causes Diplodia tip blight following host stress. The factors driving its shift from endophyte to pathogen are not well understood, particularly in relation to the surrounding fungal community. The objective of the current study was to determine the association of D. sapinea and the composition of the general endophyte community with symptomatic and asymptomatic sites, trees, twigs and tissues in an ongoing outbreak of Diplodia tip blight. The endophytic fungal community was characterized using metabarcoding of the ribosomal ITS2 region. We found that variation in fungal community composition was most influenced by differences between sites, highlighting the importance of site-specific environmental conditions such as previous drought impact and associated crown dieback. However, the fungal communities also varied between symptomatic and asymptomatic trees indicating the significance of tree health. The fungal communities of symptomatic trees, especially in twigs with tip blight symptoms, included D. sapinea, Therrya pini, and Lophodermium arboricola. These results are consistent with the balanced antagonism hypothesis, suggesting that shifts in community composition under stress may facilitate the transition of D. sapinea from a latent endophyte to a pathogen. D. sapinea was found in both healthy and symptomatic twigs, with a ∼60-fold increase in symptomatic tissues. Site differences accounted for 42.6 % of fungal community variation. In contrast, taxa from the order Phaothecales were more abundant in asymptomatic twigs and in healthy tissues of of symptomatic twigs - suggesting potential antagonism. Our findings provide insights into early disease detection and underscore the importance of monitoring endophyte community shifts to support Scots pine forest resilience under climate stress.