Departamento Biología Animal, Ecología, Parasitología, Edafología y Química Agrícola

Controlling human activities as confounding variable in road studies

2026-05-09T00:01:16Z

[EN]Roads cause disturbances to wildlife from the beginning of their construction and once the road is in operation, people usually make use of the habitats, reducing their quality. To this are added the effects caused by light and noise from vehicles. These propagate through the land adjacent to the road causing changes in the fauna’s use of the habitat. This led us to ask ourselves what attributes inherent to the road and terrain influence the vertebrate fauna and what factors associated with human activities can be considered as confounding variables for the results interpretation? The study was conducted in proximity of the 40D highway in Mexico. Three paired areas were selected where signs of wildlife presence were recorded during spring and fall from 2018 to 2020 and these data were used as response variable (2108 records of 49 species). We used as explanatory variables the inherent characteristics of the natural terrain and road (e.g., height difference between road and habitat, distance from road), as well as those related to human presence in the habitat (e.g., distance to nearest town). GLM’s were adjusted to determine the influence of these on our response variable. We found that the inherent variables of the road and terrain have a significant influence on the number of faunal of hunting interest traces found (p = 0.018, r2 = 23.09). The method used allowed us to identify and distinguish the influence that human activities exert on the fauna within the road’s influence zone. The differential way in which organisms respond to human presence and activity makes it difficult to isolate this effect from the one we wish to evaluate, such as that of the road. Therefore, it is suggested that the variables used in this study be used as a control measure of this effect in the work carried out in proximity of roads.

COVID-19 related travel restrictions prevented numerous wildlife deaths on roads: A comparative analysis of results from 11 countries

2026-05-09T00:01:25Z

[EN]Millions of wild animals are killed annually on roads worldwide. During spring 2020, the volume of road traffic was reduced globally as a consequence of the COVID-19 pandemic. We gathered data on wildlife-vehicle collisions (WVC) from Czechia, Estonia, Finland, Hungary, Israel, Norway, Slovenia, Spain, Sweden, and for Scotland and England within the United Kingdom. In all studied countries WVC statistics tend to be dominated by large mammals (various deer species and wild boar), while information on smaller mammals as well as birds are less well recorded. The expected number of WVC for 2020 was predicted on the basis of 2015–2019 WVC time series representing expected WVC numbers under normal traffic conditions. Then, the forecasted and reported WVC data were compared. The results indicate varying levels of WVC decrease between countries during the COVID-19 related traffic flow reduction (CRTR). While no significant change was determined in Sweden, where the state-wide response to COVID-19 was the least intensive, a decrease as marked as 37.4% was identified in Estonia. The greatest WVC decrease, more than 40%, was determined during the first weeks of CRTR for Estonia, Spain, Israel, and Czechia. Measures taken during spring 2020 allowed the survival of large numbers of wild animals which would have been killed under normal traffic conditions. The significant effects of even just a few weeks of reduced traffic, help to highlight the negative impacts of roads on wildlife mortality and the need to boost global efforts of wildlife conservation, including systematic gathering of roadkill data.

Effect of Protected Areas on Human Populations in the Context of Colombian Armed Conflict, 2005–2018

2026-05-09T00:01:23Z

[EN]It is widely recognised that conservation policies in protected areas must also favour the development and viability of human populations. Although much research has focused on economic consequences, understanding the real impact of conservation on local populations requires a more holistic standpoint. Using quasi-experimental matching methods and a diachronic perspective, the biodemographic and socio-economic effects of Colombia’s National Natural Parks (NNPs) were evaluated (all in a context of internal conflict and post-conflict). The analyses were made for the set of NNPs and then grouped into four natural regions (Andes, Caribbean, Amazon-Orinoquía and Pacific) and two conflict intensities. Differences were found mainly for NNPs with low-intensity conflict, but only for biodemographic variables, not for socio-economic ones. Starting from a situation of disadvantage, a relative improvement in the conditions of the NNP municipalities was observed throughout the 13-year period in relation to the control group. Results should be taken with caution due to the conflict situation, but the lack of correlation between biodemographic and socio-economic aspects highlights the need to include more complex approaches in protected area management policies.

Connectivity Predicts Presence but Not Population Density in the Habitat-Specific Mountain Lizard Iberolacerta martinezricai

2026-05-09T00:01:21Z

[EN]The Batuecan lizard Iberolacerta martinezricai is a critically endangered species due to its significantly reduced distribution, which is restricted to the scree slopes (SS) of a few mountain peaks within the Batuecas-Sierra de Francia Natural Park (western Spain). Given its high specialisation in this type of discontinuous habitat, the long-term conservation of the species requires maintaining the connectivity between populations. This study analyses the contribution of connectivity, as well as other patch-related factors, in the distribution and density patterns of the species. With this aim, 67 SS were sampled by line transects from May to October 2018. Each SS was characterised using variables indicative of the microhabitat conditions for the lizard. Inter-SS connectivity was quantified using graph theory for seven distances. Generalised linear models (GLMs) were performed for both presence and density. Model results showed that while connectivity was a relevant factor in the presence of lizards, density only involved patch-related variables. Discrepancies probably occurred because the factors influencing presence operate on a wider scale than those of abundance. In view of the results, the best-connected SS, but also those where the lizard is most abundant and from which more dispersed individuals are likely to depart, seem to be the essential patches in any conservation strategy. The results may also be relevant to other species with habitat-specific requirements.

Restauración de antiguas minas de carbón a cielo abierto en el suroeste de Asturias : un modelo hacia la sostenibilidad

2026-01-16T01:01:32Z

[SPA]El cierre de minas de carbón en el suroccidente de Asturias dejó un paisaje degradado con suelos empobrecidos y ecosistemas fragmentados. Para su restauración, se proponen soluciones basadas en la naturaleza (SBN) y economía circular. Se evalúa la efectividad de enmiendas como compost, residuos industriales inertes y biochar en la recuperación del suelo y la revegetación, tanto en laboratorio como en parcelas piloto en la mina de Tormaleo (Ibias). Los resultados indican mejoras en la fertilidad del suelo, regeneración vegetal, secuestro de carbono y fortalecimiento de servicios ecosistémicos. Estas estrategias pueden replicarse en otros entornos mineros, consolidando prácticas sostenibles para la restauración ambiental y la transición ecológica

Soil Remediation and Improvement through the Application of By-Product Amendments

2026-01-16T01:01:29Z

This Reprint compiles recent research on the remediation and improvement of soils through the application of by-product amendments. The contributions address the dual challenge of soil degradation and waste overproduction by exploring how organic and industrial residues can be repurposed to restore soil health and enhance fertility. The articles cover a wide range of contexts, from contaminated mine soils to agricultural lands, and assess impacts on nutrient availability, microbial communities, crop productivity, and pollutant mitigation. Several studies also integrate techniques such as phytoremediation and vermicomposting. This Reprint highlights interdisciplinary approaches that connect biotechnology, ecology, and sustainable waste management, offering practical perspectives for regenerative agriculture and circular economy strategies.

Estimating Mercury and Arsenic Release from the La Soterraña Abandoned Mine Waste Dump (Asturias, Spain): Source-Term Reconstruction Using High-Accuracy UAV Surveys and Historical Topographic Data

2026-01-15T01:01:48Z

[EN]The waste dump from the abandoned La Soterraña mine, a former mercury extraction site, contains high concentrations of mercury (Hg) and arsenic (As), which pose a significant environmental risk due to direct exposure to the environment. Given the site’s topography and slope, surface runoff has been identified as the primary mechanism for the dispersal of these toxic elements into nearby watercourses. This study quantifies the amount of Hg and As released into fluvial systems through surface runoff from the waste dump. Historical topographic data, Airborne Laser Exploration Survey public data from the National Plan for Aerial Orthophotographs (1st PNOA-LiDAR) of the Spanish Ministry of Transport, Mobility and Urban Agenda, and high-precision photogrammetric drone surveys were utilized, with centimeter-level accuracy achieved using airborne GNSS RTK positioning systems on the drone. The methodology yields reliable results when comparing surfaces generated from topographic data collected with consistent methodologies and standards. Analysis indicates an environmental release exceeding 1000 kg of mercury (Hg) and 12,000 kg of arsenic (As) between 2019 and 2023, based on high spatial resolution data (GSD = 8 cm). These findings highlight a sustained temporal contribution of chemical contaminants, which imposes serious environmental and biological health risks due to persistent exposure to toxic elements.

From waste to solution: Valorisation of a dolomite by-product for degraded soil rehabilitation

2026-01-15T01:01:43Z

[Acidic, metal(loid)-contaminated soils require scalable circular solutions; the efficacy of a finely milled dolomite by-product, alone or co-applied with vermicompost (VC) or biochar (B), was assessed as amendments to rehabilitate an Iberian mine-impacted soil and to enable phytostabilisation with Lolium multiflorum. In a greenhouse pot trial comparing five amended treatments (SD, SV, SB, SVD, SBD) against an unamended control, soil chemistry (pH, C/N, available P, CEC, Al saturation), TCLP-extractable Cu–Zn–As, plant biomass, and multivariate response (PCA) were quantified. Dolomite sharply neutralised acidity (pH 3.1→8.3–8.5), increased CEC (23.0→65.5–81.9 cmol(+)/kg), and reduced Al saturation (11.2 % → ~0.02 %), with large decreases in TCLP-Cu fell to <10 mg/kg in dolomite-containing treatments and to <3 mg/kg with VC formulations; Zn was suppressed to <65 mg/kg except where liming counteracted B effects. Arsenic showed a distinct pattern: VC increased TCLPAs in close association with available P, whereas dolomite alone or with B kept As below detection—most plausibly via Ca/Mg-driven (co)precipitation of sparingly soluble arsenate/phosphate phases; notably, SVD < SV for As, indicating partial mitigation by dolomite. Vegetation failed in the control but established across all amended soils, with biomass maximized under VC. Overall, the results indicate that dolomite by-product particularly in combination with VC provides a circular, field-relevant route to restore soil function and reduce bioavailable Cu and Zn by >90 % while sustaining plant establishment; given VC-linked As mobilization, co-amendment with Fe-rich sorbents and prudent P management are recommended to minimize risk in practical applications.

Application of organic geochemistry to the characterization of hydrochar and biochar: Insights into composition and optimization

2026-01-15T01:01:28Z

[EN]Hydrothermal carbonization has garnered significant attention in recent studies due to potential applications of the hydrochar produced, which overlap with those of torrefied biochar, including soil improvement, carbon sequestration, and energy production. However, unlike the relatively uniform properties of biochar, hydrochar characteristics can vary greatly depending on the feedstock used. Advanced characterization techniques are essential to better understand these materials and enhance their practical applications. Research on hydrochar requires a multi-faceted approach, including molecular-level studies, to optimize production processes and identify specific applications. In this regard, analytical methods commonly used in organic geochemistry could play a crucial role in deepening our knowledge of hydrochar and biochar. Thus, this study evaluates the properties and key characteristics of five types of hydrochar and a reference biochar using a range of advanced analytical techniques. Among these, HAWK® pyrolysis with flame ionization and infra-red detectors (Py-FID/IRD) — typically employed in petroleum geochemistry — has proven to be a rapid and effective method for assessing some key properties and facilitating quick comparisons. Additionally, thermal desorption and pyrolysis analysis followed by gas chromatography coupled with mass spectrometry (TD-Py-GC-MS) provided detailed molecular characterizations of the hydrochars. These findings demonstrate that traditional techniques used in fossil fuel and environmental geochemistry are equally applicable in this field. Consequently, these techniques offer valuable insights into hydrochar composition, addressing critical knowledge gaps and leveraging advanced geochemical methods to assist in optimizing carbonaceous materials for practical applications including production of biofuels and platform chemicals for bio-refining.

Unraveling the dynamic interplay of microbial communities associated to Lupinus angustifolius in response to environmental and cultivation conditions

2025-11-28T01:01:46Z

[EN]Microorganisms form dynamic communities with plants, providing benefits such as nutrient acquisition and stress resilience. Understanding how these microorganisms are affected by environmental factors such as growth conditions and soil characteristics are essential for harnessing these communities for sustainable agriculture practices and their response to climate change. The microbiome associated to Lupinus angustifolius, a legume native in Europe, with a high protein value and stress resilience was characterized for the first time. Using 16S rRNA gene and ITS amplicon sequencing, we characterized the compositional and temporal changes of the bacterial and fungal communities associated to the soil, rhizosphere, and plant compartments where Lupinus angustifolius grows naturally. Our results suggest that the main difference in the soil microbial communities is related to the edaphic properties, although environmental factors such as temperature, humidity or rainfall also influenced the composition of the soil microbial communities. We also characterized the bacterial communities associated with the rhizosphere, roots, nodules, and leaves of wild plants collected in the field and compared them against plants obtained under greenhouse conditions. In the plant compartments, the bacterial composition appeared to be more affected by the growing conditions (field vs greenhouse), than by soil characteristics or location. These results can be used to identify key taxa that may play crucial roles in the development and adaptation of the host plant and its associated microbiota to environmental changes and highlight the importance of characterizing the plant microbiomes in their natural habitats. Soil, influenced by climatic seasons, shapes the plant microbiome assembly. Lupinus recruits a core microbiome across rhizosphere, roots, nodules, and leaves, that is stable across locations. However, cultivation conditions may alter microbiome dynamics, impacting the adaptability of its components. Wild plants show a resilient and adaptable microbiome while germination and cultivation in greenhouse conditions alter its composition and vulnerability.

Improving the Management of a Semi-Arid Agricultural Ecosystem through Digital Mapping of Soil Properties: the case of Salamanca (Spain)

2025-11-27T11:59:20Z

[EN]Soil protection and the increase and intensification of agricultural production require detailed knowledge of soil properties and their variability. On the other hand, the complexity associated with traditional soil mapping processes can lead to the implementation of inappropriate agricultural practices that degrade this resource. Therefore, it is necessary to use mapping techniques to provide more detailed information to farmers and managers. In this study, the geostatistical technique ordinary kriging was used to map the distribution of the most important edaphic properties (texture, nutrients content -N, P, K-, pH, organic carbon, water retention, COLE, carbonate content, and cation exchange capacity) from known sampled points, which allows inferring the value and distribution of the different edaphic parameters studied along the agricultural fields. The results obtained show after validation that the analysis of semivariograms is suitable for evaluating the distribution of the main soil parameters on a large scale, since it faithfully reflects their distribution and makes the ordinary kriging tool a suitable method for optimizing the resources available in soil mapping processes. In addition, the knowledge of these distributions made it possible to establish different recommendations for improving the management of the agricultural ecosystem, which will guarantee a higher agricultural yield as well as a better protection of the analyzed soils.

Diversity and dominance in bird assemblages across habitats in the Ñeembucú wetlands complex

2025-08-01T00:02:03Z

[EN] Understanding how diversity responds to habitat heterogeneity in a landscape is a central issue for implementing effective conservation plans. In this study, we analyzed how the composition and abundance of neotropical bird assemblages vary among habitats in the Ñeembucú Wetlands Complex, the largest wetland system in Paraguay. Bird surveys were conducted during 1 year within dominant habitats in the landscape: riparian forests, natural grasslands, savannas, and anthropized sites. The Ñeembucú Wetlands Complex showed a high bird richness (209 species) that contrasted with a pattern of dominance by a small set of 16 species that comprised half of the abundance. This set of oligarchic species consists of generalist species that exploited a wide variety of habitats and were well adapted to human disturbance, contributing to an important overlap in the composition of assemblages. However, despite this overall similarity, there is still significant differentiation in bird assemblages, especially between habitats with the most contrasting vegetation physiognomy. Riparian forests and savannas showed higher diversity values than the more structurally homogeneous grasslands. Also, all natural habitats showed, in general, higher diversity values than anthropized sites. Oligarchic species had higher importance in anthropized environments, which also had the most uneven distribution of abundance between species, indicating the dominance by a smaller number of species and the loss of ecological diversity as farmland and urban development increase.

Interacción entre los helmintos parásitos y el sistema hemostático de sus hospedadores. La larva infectiva de Ascaris suum como modelo experimental

2025-05-23T01:11:21Z

[ES]Los helmintos parásitos constituyen uno de los grupos de agentes infecciosos más comunes, tanto de humanos como de animales. Estos parásitos llevan coevolucionando con sus hospedadores miles de años, lo que ha supuesto la aparición de interacciones finamente reguladas y equilibradas entre ambos organismos. Entre ellas destacan las diversas estrategias que los parásitos han desarrollado para afrontar y evadir las respuestas de sus hospedadores y adaptar o modificar la fisiología de estos a sus propias necesidades. Una de estas estrategias es la manipulación que hacen del sistema hemostático, mecanismo responsable de mantener la integridad vascular en los vertebrados mediante la formación de coágulos sanguíneos (sistema de la coagulación) y la posterior disolución de los mismos (sistema fibrinolítico). La información existente en este campo de estudio es cuantiosa y diversa y se encuentra dispersa en la literatura científica. Por ello, el primer objetivo de la Tesis Doctoral fue realizar una revisión de alcance para revisar, sintetizar y unificar esta información, actualizar conceptos e identificar vacíos de conocimiento. Los resultados revelaron un número considerable de especies de helmintos parásitos con capacidad para interaccionar con el sistema hemostático en diferentes estadios evolutivos. Las interacciones que llevaron a cabo resultaron, principalmente, en la inhibición de la coagulación y la activación de la fibrinolisis. Se identificó un número elevado de proteínas parasitarias como responsables de interaccionar con un gran número de componentes del sistema hemostático, las cuales presentaron cierta homología con los moduladores fisiológicos de este sistema en el hospedador. Las distintas especies mostraron un patrón común de interacción, lo que sugiere procesos de convergencia evolutiva que podrían haberse conservado al ser beneficiosos para la nutrición, el establecimiento y la supervivencia del parásito en el hospedador. Con el objetivo de estudiar experimentalmente este tipo de interacciones, se empleó la larva infectiva de Ascaris suum, la cual realiza una extensa ruta migratoria por diferentes tejidos de su hospedador a través de la circulación sanguínea del mismo. Este helminto es el parásito intestinal más prevalente en cerdos domésticos de todo el mundo, presenta potencial zoonótico y se encuentra muy próximo filogenéticamente a A. lumbricoides, especie que afecta al ser humano con más de 800 millones de casos en el mundo. Los resultados mostraron que la larva infectiva de A. suum sigue el patrón general de interacción con el sistema hemostático observado en la revisión de alcance, pues se demuestra su capacidad para inhibir componentes del sistema de la coagulación de su hospedador, así como para activar su ruta fibrinolítica. En relación con las moléculas implicadas en estos procesos, se identificaron tres y doce proteínas del parásito, respectivamente. Esta manipulación del sistema hemostático podría conferirle a dicha larva beneficios en términos de migración por los tejidos de su hospedador y, por tanto, de establecimiento y supervivencia en él. Puesto que el estudio de las relaciones parásito-hospedador se ha postulado como uno de los pilares fundamentales para el desarrollo de nuevas herramientas de control contra las helmintiasis, y debido a la importancia biológica y conservación evolutiva de este mecanismo de interacción parasitario, la información aportada por la presente Tesis Doctoral podría contribuir al futuro diseño de dichas herramientas.

Imported Mansonella perstans infection in Spain

2025-04-30T19:43:39Z

[EN] Background: Mansonella perstans infection can be considered one of the most neglected tropical infectious diseases. Very few studies have reported on the clinical picture caused by infection with this nematode. Therefore, our study was aimed to describe the clinical patterns and treatment of imported M. perstans infection by migrants from Africa. Methods: The present study evaluated a large cohort of migrants who have been diagnosed, examined and treated for imported M. perstans infection at a Spanish reference center (Hospital Carlos III Tropical Medicine Unit, Madrid, Spain) over a 19-year period. Most patients voluntarily attend the emergency unit or are referred from primary care or general hospitals in Madrid. Chi-square test was used to compare the association between categorical variables. The continuous variables were compared by Student’s t-test or the Mann–Whitney test. The corresponding regression models were used for multivariate analysis. Results: Five hundred three cases of migrants from tropical and subtropical areas with M. perstans infection were identified. Two hundred sixty-four patients were female (52.5%). The mean age (± SD) was 44.6 ± 18.2 years (range: 16–93 years). The mean time (± SD) between the arrival in Spain and the first consultation was 8.6 ± 18.0 months. The major origin of the patients was Equatorial Guinea (97.6%). Regarding the clinical picture, 257 patients were asymptomatic (54.7%) and 228 were symptomatic (45.3%); 190 patients had pruritus (37.8%), 50 (9.9%) had arthralgia, 18 patients had Calabar-like swelling (3.6%), and 15 (3%) had abdominal pain. Four hundred forty-two (87.9%) migrants had hyper-IgE, and 340 (67.6%) had eosinophilia. One hundred ninety-five patients had coinfections with other filarial nematodes (38.8%), and 308 migrants had only M. perstans infection (61.2%). Four hundred thirty-seven cases (86.9%) had been treated with anti-filarial drugs; 292 cases were treated with one antifilarial drug, and 145 cases were treated with combined anti-filarial therapy. Additionally, 20 (4%) cases received steroids and 38 (7.6%) cases received antihistamines. Conclusions: A long series of M. perstans infections is presented in sub-Saharan immigrants whose data indicate that it should be included in the differential diagnosis in patients with pruritus or analytical alterations such as eosinophilia or hyper-IgE presentation, and they also have a high number of coinfections with other microorganisms whose treatment needs to be protocolized. Keywords: Mansonellosis, Mansonella perstans, Clinical study, Immigrant, Imported diseases, Spain

Comparative genomics of the major parasitic worms

2025-04-30T19:43:39Z

[EN] Parasitic nematodes (roundworms) and platyhelminths (flatworms) cause debilitating chronic infections of humans and animals, decimate crop production and are a major impediment to socioeconomic development. Here we report a broad comparative study of 81 genomes of parasitic and non-parasitic worms. We have identified gene family births and hundreds of expanded gene families at key nodes in the phylogeny that are relevant to parasitism. Examples include gene families that modulate host immune responses, enable parasite migration though host tissues or allow the parasite to feed. We reveal extensive lineagespecific differences in core metabolism and protein families historically targeted for drug development. From an in silico screen, we have identified and prioritized new potential drug targets and compounds for testing. This comparative genomics resource provides a much-needed boost for the research community to understand and combat parasitic worms.

A Novel RT-LAMP for the Detection of Different Genotypes of Crimean–Congo Haemorrhagic Fever Virus in Patients from Spain

2025-04-30T19:43:40Z

[EN] Crimean–Congo haemorrhagic fever (CCHF) is a potentially lethal tick-borne viral disease with a wide distribution. In Spain, 12 human cases of CCHF have been confirmed, with four deaths. The diagnosis of CCHF is hampered by the nonspecific symptoms, the high genetic diversity of CCHFV, and the biosafety requirements to manage the virus. RT-qPCR and serological tests are used for diagnosis with limitations. Reverse-transcription loop-mediated isothermal amplification (RT-LAMP) could be an effective alternative in the diagnosis of the disease. However, none of the few RT-LAMP assays developed to date has detected different CCHFV genotypes. Here, we designed a RT-LAMP using a degenerate primer set to compensate for the variability of the CCHFV target sequence. RT-LAMP was performed in colorimetric and real-time tests on RT-qPCR-confirmed CCHF patient samples notified in Spain in 2020 and 2021. Urine from an inpatient was analysed by RT-LAMP for the first time and compared with RT-qPCR. The amplicons obtained by RT-qPCR were sequenced and African III and European V genotypes were identified. RT-LAMP amplified both genotypes and was more sensitive than RT-qPCR in urine samples. We have developed a novel, rapid, specific, and sensitive RT-LAMP test that allows the detection of different CCHFV genotypes in clinical samples. This pan-CCHFV RT-LAMP detected viral RNA for the first time in urine samples. It can be easily performed as a single-tube isothermal colorimetric method on a portable platform in real time and without the need for expensive equipment, thus bringing molecular diagnostics closer to rural or resource-poor areas, where CCHF usually occurs.