Videos by Manuel García Rodríguez
Se explica cuál es el límite inferior de los acuíferos
24 views
Explicación de acuíferos libres, confinados y semiconfinados (Nivel básico)
19 views
Se explican mapas geológicos con topografía plana (nivel básico)
14 views
Se explica cómo se representan planos verticales y horozontales en mapas de topogrfía no plana (n... more Se explica cómo se representan planos verticales y horozontales en mapas de topogrfía no plana (nivel básico) 8 views
Se explican los conceptos de dirección y buzamiento de planos geológicos
16 views
Se explica cómo se calcula la dirección y buzamiento de planos inclinados con topografía no plana... more Se explica cómo se calcula la dirección y buzamiento de planos inclinados con topografía no plana por el método de las horizontales (nivel básico) 18 views
Se explican los términos de acuífero, acuitardo, acuífugo y acuicludo
17 views
Papers by Manuel García Rodríguez
Williams M.A., Tronti G., Sartori Peruzzo R., García-Rodríguez M., Fazio E., Zucali M., Bollati I... more Williams M.A., Tronti G., Sartori Peruzzo R., García-Rodríguez M., Fazio E., Zucali M., Bollati I.M. (2025). Geoscience popularisation in Geoparks: A Common Workflow for Digital Outcrop Modelling from the "3GEO" IGCP 714 Project , 128-128 pp. In: Bollati IM, Brustia E, Melelli L, Monge-Ganuzas M, Pica A, Pompili R, Rodrigues J, Rouget I (Eds.) (2025). ProGEO SW Europe Regional Working Group Virtual Conference on Geoconservation (2nd Edition), Abstracts Book, 27-29 March, 128 pp.
García-Rodríguez M., Fernández-Escalante E. (2025). Geoclimbing at La Pedriza del Manzanares (Mad... more García-Rodríguez M., Fernández-Escalante E. (2025). Geoclimbing at La Pedriza del Manzanares (Madrid, Spain). Natural and anthropogenic weathering processes, 84 - 88 pp. In: Bollati IM, Brustia E, Melelli L, Monge-Ganuzas M, Pica A, Pompili R, Rodrigues J, Rouget I (Eds.) (2025). ProGEO SW Europe Regional Working Group Virtual Conference on Geoconservation (2nd Edition), Abstracts Book, 27-29 March, 128 pp.

Computers & Geosciences, 2025
Mark A. Williams , Gianluca Tronti , Raiza Sartori Peruzzo ,
Manuel García-Rodríguez , Eugenio F... more Mark A. Williams , Gianluca Tronti , Raiza Sartori Peruzzo ,
Manuel García-Rodríguez , Eugenio Fazio , Michele Zucali , Irene Maria Bollati (2025). Geoscience popularisation in Geoparks: A common workflow for digital outcrop modelling. Computers & Geosciences, Volume 201, 105945
Geodiversity has gained increasing attention, prompting geoscientists to advocate for its recognition to promote holistic nature conservation. UNESCO Global Geoparks (UGGps) have expanded globally, promoting geoheritage and contributing to geoconservation and sustainable tourism. In this framework, the IGCP 714 project, "3GEO-Geoclimbing & Geotrekking in Geoparks," launched in 2021, aims to use Geographical Information Technologies (GIT)-including GIS, remote sensing, Unmanned Aerial Vehicles (UAVs), and other geospatial tools-to enhance geoscience communication within UGGps. However, there is still a significant need for a repeatable, accessible, low-cost, and effective workflow to integrate these digital technologies into geoscience communication effectively. This study developed a workflow for creating Digital Outcrop Models (DOMs) of geosites and geodiversity sites used for recreational climbing and trekking. Using technologies such as UAVs and Smartphones equipped with LiDAR sensors, the workflow generates DOMs that can be integrated into web-GIS applications and Virtual Reality experiences, offering interactive educational content. Four examples are described, illustrating the implementation of the DOM workflow from the outcrop scale (La Pedriza Granitic Batholith, Spain, and Etna Volcano Lava Tube, Italy) to the terrane scale (Organ Pipes Columnar Jointing, Australia, and Baceno Tectonic Window, Italy). The workflow is designed to produce DOMs for public and student engagement, demonstrating their potential for broader educational and geoconservation applications. Moreover, the workflow aims to build capacity among Geopark practitioners and researchers by improving techniques for creating content on geoheritage features and enhancing geoscience communication. For this, the workflow is designed to be repeatable by employing common and relatively low-cost GIT tools. We discuss the need for investment in capability, software, and hardware to equip Geopark practitioners with the skills required to implement this workflow. By applying this workflow to create DOMs of geoheritage features, we demonstrate its potential to enhance the appreciation of geodiversity, support education and research, and promote sustainable geotourism within UGGps.

Geoheritage 16:79, 2024
Irene Maria Bollati, Anna Masseroli, Mohammed Al Kindi, Lucas Cezar, Anna Chrobak‑Žuffová, Ashish... more Irene Maria Bollati, Anna Masseroli, Mohammed Al Kindi, Lucas Cezar, Anna Chrobak‑Žuffová, Ashish Dongre, Charalampos Fassoulas, Eugenio Fazio, Manuel Garcia‑Rodríguez, Jasper Knight, Jack J. Matthews, Ricardo Galeno Fraga de Araújo Pereira, Cristina Viani, Mark Williams, Giuseppe M. Amato, Tiziana Apuani, Emanuel de Castro, Enrique Fernández‑Escalante, Magda Fernandes, Martina Forzese, Franco Gianotti, Gabriel Goyanes, Fabio Loureiro, Avinash Kandekar, Maria Koleandrianou, Rosanna Maniscalco, Emmanouel Nikolakakis, Mauro Palomba, Manuela Pelfini, Gianluca Tronti, Enrico Zanoletti, Andrea Zerboni, Michele Zucali. (2024). The IGCP 714 Project “3GEO – Geoclimbing & Geotrekking in Geoparks” – Selection of Geodiversity Sites Equipped for Climbing for Combining Outdoor and Multimedia Activities. Geoheritage 16:79. DOI: 10.1007/s12371-024-00976-4. License CC BY 4.0. Open Access
Revista Desnivel, 2023
García-Rodríguez, M. (2023). Geología de Galayos. Magma, hielo y roca. Revista Desnivel, 430. Pág... more García-Rodríguez, M. (2023). Geología de Galayos. Magma, hielo y roca. Revista Desnivel, 430. Pág. 60.
Diversity, 2023
Velasco-González, Ismael, Enrique Lara, David Singer, Amaya de Cos-Gandoy, Manuel García-Rodrígue... more Velasco-González, Ismael, Enrique Lara, David Singer, Amaya de Cos-Gandoy, Manuel García-Rodríguez, Antonio Murciano, Blanca Pérez-Uz, Richard Williams, Abel Sanchez-Jimenez, and Mercedes Martín-Cereceda. 2023. "Diversity of DNA Sequences from Pathogenic and Potentially Pathogenic Eukaryotic Microorganisms in Protected Granite Mountain Rocks" Diversity 15, no. 5: 594. https://doi.org/10.3390/d15050594

Surface Mechanical Effects of Wildfires on Rocks in Climbing Areas
Fire 6(2):46 , 2023
Yeste-Lizán P, Gomez-Heras M, García-Rodríguez M, Pérez-López R, Carcavilla L, Ortega-Becerril JA... more Yeste-Lizán P, Gomez-Heras M, García-Rodríguez M, Pérez-López R, Carcavilla L, Ortega-Becerril JA. Surface Mechanical Effects of Wildfires on Rocks in Climbing Areas. Fire. 2023; 6(2):46. https://doi.org/10.3390/fire6020046.
Wildfires are widely recognized as a cause of mechanical damage to rocks. Nevertheless, previous research has neglected how wildfires might impact sport climbing areas. In Spain, two large wildfires affected two climbing areas between 2020 and 2021. This paper addresses the rock mechanical effects of wildfires that could lead to safety issues, such as rock falls, climbing hold deterioration, and climbing anchor damage. In this study, the Non-Destructive Techniques (NDTs) of Ultrasonic Pulse Velocity (UPV) and Schmidt Hammer (SH) were used, and two types of measurements were carried out: randomized grid measurements and measurements along the climbing routes. Two phenomena were recognized: (a) thermal breakdown and (b) mineralogical changes. The results of using the SH show a relationship between the decrease in the rebound value and the observed mechanical damage. Field observations showed mechanical weathering, such as cracking, spalling, granular disaggregation, and thermochemical weathering with different temperature thresholds. Observed thermochemical reactions included reddening, CaCO3 calcination, rock decomposition, and quartz cracking. The set of changes involves a major rock outcrop transformation and an acceleration of fire-induced weathering processes. Both areas exhibited more effects at the bottom of the wall. Furthermore, in this paper, we explore how iconic climbing routes can be considered a form of cultural heritage and the consequences of their loss.
Geología: las 10 mejores vías para escalar en la Pedriza.
El Cohete, Magazine de Escalada, Sputnik, 2022
García Rodríguez, M (2022). Geología: las 10 mejores vías para escalar en la Pedriza. El Cohete, ... more García Rodríguez, M (2022). Geología: las 10 mejores vías para escalar en la Pedriza. El Cohete, Magazine de Escalada, Sputnik. https://dev.elcohete.sputnikclimbing.com/10-mejores-vias-pedriza-2/
La Pedriza es la escuela de escalada en adherencia más importante de España y, aunque a simple vista puede parecer que todas las vías son iguales, sus paredes tienen una serie de rasgos geomorfológicos, a veces muy sutiles, que condicionan su dificultad. Las micro-lajas, acanaladuras, fisuras, tafonis o diques hacen que la escalada sea muy variada.
Manuel García Rodríguez, autor del libro La Pedriza. Geología y escalada, ha seleccionado las 10 vías más representativas, geológicamente hablando, de esta escuela donde predomina la adherencia.
Desnivel, 2022
García Rodríguez, M. (2022). Geología y escalada. Especial Pedriza. Monumento al granito. Rev.Des... more García Rodríguez, M. (2022). Geología y escalada. Especial Pedriza. Monumento al granito. Rev.Desnivel, nº 425, pág.96.

Cartografía de presión por ungulados en Parques Nacionales y fincas de caza: una herramienta útil para la gestión
XIII Reunión de Ungulados Silvestres Ibéricos. Potes (Cantabria), 7 - 8 de octubre 2022. pág. 24., 2022
Ramón Perea, Marta Peláez, Pedro Domínguez, Guillermo Carranza, Daniel Gambra,Carlota Solano, Aid... more Ramón Perea, Marta Peláez, Pedro Domínguez, Guillermo Carranza, Daniel Gambra,Carlota Solano, Aida López-Sánchez, José María Fedriani, Pablo Refoyo, Manuel García-Rodríguez (2022). Cartografía de presión por ungulados en Parques Nacionales y fincas de caza: una herramienta útil para la gestión. XIII Reunión de Ungulados Silvestres Ibéricos. Potes (Cantabria), 7 - 8 de octubre 2022. pág. 24.
Las poblaciones de ungulados silvestres en España han crecido en las últimas décadas como consecuencia de múltiples factores ligados al cambio del uso del suelo y a importantes trasformaciones socioeconómicas. Los Parques Nacionales de España, y muchas fincas de caza menor y mayor, no son ajenos a esta tendencia y precisan, por tanto, de conocimiento científico para gestionar adecuadamente las poblaciones crecientes de ungulados. En este trabajo se analiza el impacto que ejercen los ungulados sobre componentes básicos del ecosistema (suelo, flora, vegetación), y se buscan indicadores ecológicos y especies indicadoras que sirvan para determinar la carga admisible desde el punto de vista de la conservación del sistema (diversidad vegetal, abundancia y estructura de regenerado, cobertura de suelo afectado, etc.). Para ello se han establecido más de 300 parcelas repartidas homogéneamente por Parques Nacionales dominados por ungulados silvestres
(Cabañeros, Doñana, Sierra de Guadarrama y Monfragüe) y fincas de caza mayor.
Los resultados permiten obtener una cartografía de presión por ungulados, estableciendo una zonificación de la presión herbívora (ramoneo) o presión por jabalí (hozaduras) que se puede relacionar directamente con las abundancias relativas (excrementos) y absolutas, y determinar, así, las cargas admisibles. Todos los Parques Nacionales estudiados muestran presiones herbívoras insostenibles en buena parte de su superficie (entre 35% y 73% de su superficie). Doñana, además, presenta una gran afección por jabalí, estimada por la cobertura de hozaduras que afecta al suelo. Es interesante destacar que la cobertura de musgo sobre las rocas resultó ser un buen indicador en zonas pedregosas como el P.N. Sierra de Guadarrama, donde altas presiones de cabra montés redujeron un 62% la cobertura de musgos. La cartografía de presión permite identificar las zonas y hábitats más vulnerables, los cambios temporales y espaciales y determinar la carga admisible global del sistema y
de los diferentes hábitats, aplicable tanto a espacios protegidos como a fincas cinegéticas.
Palabras clave. ungulados silvestres, monte mediterráneo, indicadores ecológicos, cérvidos, cabra montés, jabalí, sistemas de información geográfica.

Study of the deterioration pattern of cyclically emerged and submerged cultural heritage in freshwater reservoirs.
IKUWA7, 2022
Sáez A, Álvarez de Buergo M, Fort, Varas-Muriel M, Perez-Ema N, García Rodríguez M, Maté-González... more Sáez A, Álvarez de Buergo M, Fort, Varas-Muriel M, Perez-Ema N, García Rodríguez M, Maté-González M, Aguirre de Mata J, Sánchez-Aparicio L, Lopez-Cuervo S, Villanueva P. (2022). Study of the deterioration pattern of cyclically emerged and submerged cultural heritage in freshwater reservoirs. Internationaler Kongreß für Unterwasserarchäologie, IKUWA7, 6-9th of June 2022 in Helsinki.
Humans have added over half a million artificial lakes to the world's surface by building large -at least 1 Ha- engineered dams for water supply. Spain is one of the countries with the largest number of water reservoirs in the world (> 1,200), many of them covering archaeological sites and even whole villages. In the past few years, some of these cultural heritage elements have emerged partially or completely out of these reservoirs, mainly due to drought periods.
Unlike underwater cultural heritage, the deterioration pattern of these sites has not been studied. Heritage in reservoirs suffers a deterioration that is accelerated by the rapid rises and falls of the water level, which are mainly due to seasonal changes in dry and wet periods. This causes the cyclical emersion and submersion of heritage sites, comparable to an accelerated wetting and drying artificial aging test.
The work presented here aims to establish the methodology for the analysis of the deterioration of cultural heritage building materials in dammed water environments, using for this purpose mainly portable, in situ, and minimal to non-destructive techniques (surface, hydric, chemical, and mechanical properties) and microclimatic control techniques (environmental monitoring). All these tests are complemented by several geoinformatics methods, such as 3D point clouds, and orthoimages by means of terrestrial and aerial photogrammetry that allow the spatial analysis of these structures.

Moss cover and browsing scores as sustainability indicators of mountain ungulate populations in Mediterranean environments
Biodiversity and Conservation, 2022
Refoyo, P., Peláez, M., Pelaez, M.,García-Rodríguez, M. López Sanchez, A., Perea, R. (2022). Moss... more Refoyo, P., Peláez, M., Pelaez, M.,García-Rodríguez, M. López Sanchez, A., Perea, R. (2022). Moss cover and browsing scores as sustainability indicators of mountain ungulate populations in Mediterranean environments. Biodivers Conserv 31, 2741–2761 (2022). https://doi.org/10.1007/s10531-022-02454-1. Q1, JCI: 0,79
Here, we aimed to define ecological indicators of environmental change for monitoring the effect of a reintroduced species, the Iberian ibex (Capra pyrenaica), over the vegetation of a natural protected area with contrasting habitats. This species was reintroduced 30 years ago in the Sierra de Guadarrama National Park, Spain, and its population has since grown exponentially, reaching high densities in some areas. We tested the suitability of two complementary indicators: browsing damage on woody species and the percentage of moss cover loss on rocky outcrops. For this purpose, we used a mathematical approach to zone the natural protected area according to the historical presence of the species and established five different Iberian ibex pressure classes (Classes I–V). Our results showed a direct link between Iberian ibex pressure and vegetation status. Model predictions suggested 10% moss loss in the areas with low pressure (Class I) but 64% loss in the areas with high pressure (Class III), mostly due to ungulate trampling on rocks. Similarly, browsing damage increased with increasing pressure classes for different woody species. Low palatable plant species such as Pinus spp. showed little change in browsing damage for increasing ungulate pressure whereas more palatable plants (e.g., Erica arborea) showed significantly greater browsing damage variation across pressure classes (i.e., high sensitive to herbivory pressure). Both, moss cover on rocks and widely distributed palatable woody plants proved useful ecological indicators for monitoring ungulate populations in mountainous areas with a diverse array of habitats (e.g., rocky vs. woody). This methodology may help select the most suitable indicators for each type of ecosystem or dominant habitat in ungulate-dominated ecosystems.
¿Es sostenible la sobrepoblación de cabra montés?
El Guadarramista, 2021

Euro-Mediterranean Journal for Environmental Integration, 6: 76., 2021
García-Rodríguez, M., Vélez, J.A., López-Sánchez, A. et al. A pressure indicator for the impact o... more García-Rodríguez, M., Vélez, J.A., López-Sánchez, A. et al. A pressure indicator for the impact of Iberian wild goat on moss and soils in a Mediterranean climate. Euro-Mediterr J Environ Integr 6, 76 (2021). https://doi.org/10.1007/s41207-021-00283-2. Q4, JCI: 036 (2021).
In the Sierra de Guadarrama National Park (central Spain), the population of Iberian wild goat, also known as Spanish ibex (Capra pyrenaica) has grown strongly since its reintroduction three decades ago. The plant community is now under heavy browsing pressure due to this high population. A study of the presence of moss on rocks was used herein as the basis for the design of an indicator, named impact on mosses (im), to describe the environmental pressure exerted by the Iberian wild goat in terms of moss removal. Granite and gneiss zones at medium altitudes with continental Mediterranean climate are the most suitable areas for successful application of the indicator. The hypotheses to test are: (1) the indicator will discriminate between areas with different wild goat pressure levels, (2) wild goat pressure will explain a high proportion of moss loss variance, and (3) the im indicator will be useful to establish a mathematical model between wild goat pressure and moss loss. The proposed indicator was analyzed using both statistical and data science techniques. The results support the mentioned hypotheses. Specifically, statistically significant differences were found regarding the impact on mosses between areas with different levels of Iberian wild goat pressure. Thus, a high proportion of the variance was associated with wild goat pressure (80% for high-pressure areas, 56% for low-pressure areas). A modified parabolic function was fit to express the relationship between Iberian wild goat pressure and impact on mosses. In conclusion, the im indicator was shown to be a useful tool to assess pressure due to Iberian wild goat. Therefore, im can help assess and manage Iberian wild goat populations and determine their sustainable levels.

Limnetica, 40(1): 1-18 (2021). , 2021
Pérez-Uz, B., Velasco-González, I., Murciano, A., Sanchez-Jimenez, A., García-Rodríguez, M., Cent... more Pérez-Uz, B., Velasco-González, I., Murciano, A., Sanchez-Jimenez, A., García-Rodríguez, M., Centeno, J.D., Montero, E., Muñoz, C., Quintela-Alonso, P., Refoyo, P., Williams R and MercedesMartín-Cereceda (2021). Rain-fed granite rock pools in a national park: extreme niches for protists. Limnetica, 40(1): 1_18 (2021). 18 pp. Q3, JCI: 0,53
Rain-fed granite rock pools in a National Park: extreme niches for protists Rain-fed granite rock pools are geological landforms with a worldwide distribution. However, their role as habitats for microorganisms has been barely explored. We carried out a detailed morphological inventory of the ciliated protists in the sediments of three granite rain-fed rock pools from a Spanish National Park. The ciliate seed bank in the rock pools comprised 54 morphospecies. The species number inferred for each pool by rarefaction analysis was similar to that observed by microscopy. The most representative species were small bacterivorous ciliates, although the distribution of ciliate groups was significantly different in each rock pool. Testate amoebae were also found to be rich in species. This study demonstrates the existence of a diverse ciliate community adapted to persist in these ephemeral and extreme rock pool habitats through species resistance structures, many of which have not been described previously. The presence of competitive species in dormant stages prevents local extinctions through a sequential excystation over time. Our results provide a benchmark for studying protist and microbial biodiversity within rain-fed granite rock pools, a unique habitat that merits bio-and geo-conservation.

Observatorio Medioambiental, 21, 203-226., 2018
López Portillo, H., García-Rodríguez, M. y Merino García, J. (2018): Itinerario didáctico, ambien... more López Portillo, H., García-Rodríguez, M. y Merino García, J. (2018): Itinerario didáctico, ambiental y cultural por Valdemorillo (Madrid). Observatorio Medioambiental, 21, 203-226.
Se describe un itinerario didáctico, ambiental, y cultural por la zona sur de Valdemorillo (Madrid). Su objetivo es promover la educación ambiental y ser útil a profesores y educadores de distintas disciplinas y niveles educativos. El artículo trata los conceptos de “itinerario didáctico”, “itinerario cultural”, “Patrimonio” y “turismo cultural”. Pretende poner de manifiesto la utilidad de los itinerarios para la educación formal y no formal. Propone una ruta que detalla los recursos geológicos, hidrologicos, los ecosistemas, la flora y la fauna. Al final sugiere unas actividades a desarrollar para educadores.
Palabras clave: Itinerario didáctico; itinerario cultural; Patrimonio Natural; Patrimonio Cultural; Valdemorillo; geología; ecología; fauna.
https://revistas.ucm.es/index.php/OBMD/article/view/62659/4564456548830
La playa de San Lorenzo es un lujo para la ciudad y para iniciarse en el surf. El Comercio. Gijón 30 de diciembre de 2018
El Comercio 20, 2018
García-Rodríguez, M., (2018). Erosión y pérdida de suelo en la Pedriza de Manzanares (Parque Nacional Sierra de Guadarrama). Revista 100cias@uned, nº 11, 53 - 60., 2018
La Pedriza de Manzanares representa un paisaje de gran riqueza natural, eminentemente geológico, ... more La Pedriza de Manzanares representa un paisaje de gran riqueza natural, eminentemente geológico, con formas graníticas que llaman la atención de cualquier visitante. La Pedriza se localiza entre las cumbres de la sierra de Cuerda Larga y la población de Manzanares el Real, en la Sierra de Guadarrama del Sistema Central Español. En 1930 su atractiva geomorfología la convirtió en uno de los primeros espacios protegidos españoles, declarada Sitio Natural de Interés Nacional. Durante los años sucesivos, tras ostentar diversas nuevas figuras de protección, en 2013 quedaría incluiría en la declaración del Parque Nacional de Guadarrama (Ley 7/2013 de 25 de junio).

Complexity of river ciliate communities at a national park highlights the need for microbial conservation
Aquatic Conservation: Marine and Freshwater Ecosystems, 2018
Quintela-Alonso, P., Pérez-Uz, B., Sánchez-Jiménez, A., Murciano, A., Centeno, J.D, García-Rodríg... more Quintela-Alonso, P., Pérez-Uz, B., Sánchez-Jiménez, A., Murciano, A., Centeno, J.D, García-Rodríguez, M., Montero, E., Muñoz, B., Olmedo C., Refoyo, P., Velasco-González, I., Martín-Cereceda, M. (2018). “Complexity of river ciliate communities at a National Park highlights the need for microbial conservation”. Aquatic Conservation: Marine and Freshwater Ecosystems, Volume 28 (2), 408-421 DOI:10.1002/aqc.2852. Online ISSN: 1099-0755. Q1, JCI:0,75
Abstract
1. Microorganisms play pivotal roles in aquatic ecosystems. Free‐living protists are the main components of the eukaryotic microbial communities at the base of freshwater ecosystems. Ciliate grazing channels a large proportion of organic matter into multicellular organisms. Surprisingly, ciliates and other microorganisms are neglected in global conservation schemes.
2. Interstitial ciliates were sampled in three sites of varying human pressure on the River Manzanares (La Pedriza National Park, Spain). Abundances of trophic groups and species were adjusted to a generalized linear model (GLM Poisson regression).
3. Ciliate communities were rich in species (74 morphotypes) and although traditional microscopy retrieved a high number of species that appeared only once or in low numbers, rarefaction analyses estimated much larger species richness. These results illustrate that rarefaction assays are a useful first step for exploring the extent of the ciliate cryptic diversity in freshwater ecosystems.
4. Benthic ciliate communities changed significantly, both spatially and at a short temporal scale. The fluctuating nature of the community was manifested by the presence of many ephemeral species at the same river site, revealing a complex and transient community structure. No
significant short‐term changes were observed in the physical–chemical properties. Therefore, even slight differences in the abiotic variables may cause rapid shifts of ciliate species.
5. Overall, human pressure had an effect on the interstitial (or benthic) ciliates that resulted in a reduction of species richness and their abundance.
KEYWORDS
benthos, biodiversity, ciliates, generalized linear models, human pressure, microbial habitats, protected areas, protists, river
Chamorro Villanueva, H., López Portillo, H., García-Rodríguez, M. (2017). El manantial “Los Barra... more Chamorro Villanueva, H., López Portillo, H., García-Rodríguez, M. (2017). El manantial “Los Barrancos” en Valdemorillo (Madrid) y sus aguas radiactivas. De Re Metallica, 29, 2017 pp. 65-76. Sociedad Española para la Defensa del Patrimonio Geológico y Minero. ISSN: 1888-8615.
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Manuel García-Rodríguez , Eugenio Fazio , Michele Zucali , Irene Maria Bollati (2025). Geoscience popularisation in Geoparks: A common workflow for digital outcrop modelling. Computers & Geosciences, Volume 201, 105945
Geodiversity has gained increasing attention, prompting geoscientists to advocate for its recognition to promote holistic nature conservation. UNESCO Global Geoparks (UGGps) have expanded globally, promoting geoheritage and contributing to geoconservation and sustainable tourism. In this framework, the IGCP 714 project, "3GEO-Geoclimbing & Geotrekking in Geoparks," launched in 2021, aims to use Geographical Information Technologies (GIT)-including GIS, remote sensing, Unmanned Aerial Vehicles (UAVs), and other geospatial tools-to enhance geoscience communication within UGGps. However, there is still a significant need for a repeatable, accessible, low-cost, and effective workflow to integrate these digital technologies into geoscience communication effectively. This study developed a workflow for creating Digital Outcrop Models (DOMs) of geosites and geodiversity sites used for recreational climbing and trekking. Using technologies such as UAVs and Smartphones equipped with LiDAR sensors, the workflow generates DOMs that can be integrated into web-GIS applications and Virtual Reality experiences, offering interactive educational content. Four examples are described, illustrating the implementation of the DOM workflow from the outcrop scale (La Pedriza Granitic Batholith, Spain, and Etna Volcano Lava Tube, Italy) to the terrane scale (Organ Pipes Columnar Jointing, Australia, and Baceno Tectonic Window, Italy). The workflow is designed to produce DOMs for public and student engagement, demonstrating their potential for broader educational and geoconservation applications. Moreover, the workflow aims to build capacity among Geopark practitioners and researchers by improving techniques for creating content on geoheritage features and enhancing geoscience communication. For this, the workflow is designed to be repeatable by employing common and relatively low-cost GIT tools. We discuss the need for investment in capability, software, and hardware to equip Geopark practitioners with the skills required to implement this workflow. By applying this workflow to create DOMs of geoheritage features, we demonstrate its potential to enhance the appreciation of geodiversity, support education and research, and promote sustainable geotourism within UGGps.
Wildfires are widely recognized as a cause of mechanical damage to rocks. Nevertheless, previous research has neglected how wildfires might impact sport climbing areas. In Spain, two large wildfires affected two climbing areas between 2020 and 2021. This paper addresses the rock mechanical effects of wildfires that could lead to safety issues, such as rock falls, climbing hold deterioration, and climbing anchor damage. In this study, the Non-Destructive Techniques (NDTs) of Ultrasonic Pulse Velocity (UPV) and Schmidt Hammer (SH) were used, and two types of measurements were carried out: randomized grid measurements and measurements along the climbing routes. Two phenomena were recognized: (a) thermal breakdown and (b) mineralogical changes. The results of using the SH show a relationship between the decrease in the rebound value and the observed mechanical damage. Field observations showed mechanical weathering, such as cracking, spalling, granular disaggregation, and thermochemical weathering with different temperature thresholds. Observed thermochemical reactions included reddening, CaCO3 calcination, rock decomposition, and quartz cracking. The set of changes involves a major rock outcrop transformation and an acceleration of fire-induced weathering processes. Both areas exhibited more effects at the bottom of the wall. Furthermore, in this paper, we explore how iconic climbing routes can be considered a form of cultural heritage and the consequences of their loss.
La Pedriza es la escuela de escalada en adherencia más importante de España y, aunque a simple vista puede parecer que todas las vías son iguales, sus paredes tienen una serie de rasgos geomorfológicos, a veces muy sutiles, que condicionan su dificultad. Las micro-lajas, acanaladuras, fisuras, tafonis o diques hacen que la escalada sea muy variada.
Manuel García Rodríguez, autor del libro La Pedriza. Geología y escalada, ha seleccionado las 10 vías más representativas, geológicamente hablando, de esta escuela donde predomina la adherencia.
Las poblaciones de ungulados silvestres en España han crecido en las últimas décadas como consecuencia de múltiples factores ligados al cambio del uso del suelo y a importantes trasformaciones socioeconómicas. Los Parques Nacionales de España, y muchas fincas de caza menor y mayor, no son ajenos a esta tendencia y precisan, por tanto, de conocimiento científico para gestionar adecuadamente las poblaciones crecientes de ungulados. En este trabajo se analiza el impacto que ejercen los ungulados sobre componentes básicos del ecosistema (suelo, flora, vegetación), y se buscan indicadores ecológicos y especies indicadoras que sirvan para determinar la carga admisible desde el punto de vista de la conservación del sistema (diversidad vegetal, abundancia y estructura de regenerado, cobertura de suelo afectado, etc.). Para ello se han establecido más de 300 parcelas repartidas homogéneamente por Parques Nacionales dominados por ungulados silvestres
(Cabañeros, Doñana, Sierra de Guadarrama y Monfragüe) y fincas de caza mayor.
Los resultados permiten obtener una cartografía de presión por ungulados, estableciendo una zonificación de la presión herbívora (ramoneo) o presión por jabalí (hozaduras) que se puede relacionar directamente con las abundancias relativas (excrementos) y absolutas, y determinar, así, las cargas admisibles. Todos los Parques Nacionales estudiados muestran presiones herbívoras insostenibles en buena parte de su superficie (entre 35% y 73% de su superficie). Doñana, además, presenta una gran afección por jabalí, estimada por la cobertura de hozaduras que afecta al suelo. Es interesante destacar que la cobertura de musgo sobre las rocas resultó ser un buen indicador en zonas pedregosas como el P.N. Sierra de Guadarrama, donde altas presiones de cabra montés redujeron un 62% la cobertura de musgos. La cartografía de presión permite identificar las zonas y hábitats más vulnerables, los cambios temporales y espaciales y determinar la carga admisible global del sistema y
de los diferentes hábitats, aplicable tanto a espacios protegidos como a fincas cinegéticas.
Palabras clave. ungulados silvestres, monte mediterráneo, indicadores ecológicos, cérvidos, cabra montés, jabalí, sistemas de información geográfica.
Humans have added over half a million artificial lakes to the world's surface by building large -at least 1 Ha- engineered dams for water supply. Spain is one of the countries with the largest number of water reservoirs in the world (> 1,200), many of them covering archaeological sites and even whole villages. In the past few years, some of these cultural heritage elements have emerged partially or completely out of these reservoirs, mainly due to drought periods.
Unlike underwater cultural heritage, the deterioration pattern of these sites has not been studied. Heritage in reservoirs suffers a deterioration that is accelerated by the rapid rises and falls of the water level, which are mainly due to seasonal changes in dry and wet periods. This causes the cyclical emersion and submersion of heritage sites, comparable to an accelerated wetting and drying artificial aging test.
The work presented here aims to establish the methodology for the analysis of the deterioration of cultural heritage building materials in dammed water environments, using for this purpose mainly portable, in situ, and minimal to non-destructive techniques (surface, hydric, chemical, and mechanical properties) and microclimatic control techniques (environmental monitoring). All these tests are complemented by several geoinformatics methods, such as 3D point clouds, and orthoimages by means of terrestrial and aerial photogrammetry that allow the spatial analysis of these structures.
Here, we aimed to define ecological indicators of environmental change for monitoring the effect of a reintroduced species, the Iberian ibex (Capra pyrenaica), over the vegetation of a natural protected area with contrasting habitats. This species was reintroduced 30 years ago in the Sierra de Guadarrama National Park, Spain, and its population has since grown exponentially, reaching high densities in some areas. We tested the suitability of two complementary indicators: browsing damage on woody species and the percentage of moss cover loss on rocky outcrops. For this purpose, we used a mathematical approach to zone the natural protected area according to the historical presence of the species and established five different Iberian ibex pressure classes (Classes I–V). Our results showed a direct link between Iberian ibex pressure and vegetation status. Model predictions suggested 10% moss loss in the areas with low pressure (Class I) but 64% loss in the areas with high pressure (Class III), mostly due to ungulate trampling on rocks. Similarly, browsing damage increased with increasing pressure classes for different woody species. Low palatable plant species such as Pinus spp. showed little change in browsing damage for increasing ungulate pressure whereas more palatable plants (e.g., Erica arborea) showed significantly greater browsing damage variation across pressure classes (i.e., high sensitive to herbivory pressure). Both, moss cover on rocks and widely distributed palatable woody plants proved useful ecological indicators for monitoring ungulate populations in mountainous areas with a diverse array of habitats (e.g., rocky vs. woody). This methodology may help select the most suitable indicators for each type of ecosystem or dominant habitat in ungulate-dominated ecosystems.
In the Sierra de Guadarrama National Park (central Spain), the population of Iberian wild goat, also known as Spanish ibex (Capra pyrenaica) has grown strongly since its reintroduction three decades ago. The plant community is now under heavy browsing pressure due to this high population. A study of the presence of moss on rocks was used herein as the basis for the design of an indicator, named impact on mosses (im), to describe the environmental pressure exerted by the Iberian wild goat in terms of moss removal. Granite and gneiss zones at medium altitudes with continental Mediterranean climate are the most suitable areas for successful application of the indicator. The hypotheses to test are: (1) the indicator will discriminate between areas with different wild goat pressure levels, (2) wild goat pressure will explain a high proportion of moss loss variance, and (3) the im indicator will be useful to establish a mathematical model between wild goat pressure and moss loss. The proposed indicator was analyzed using both statistical and data science techniques. The results support the mentioned hypotheses. Specifically, statistically significant differences were found regarding the impact on mosses between areas with different levels of Iberian wild goat pressure. Thus, a high proportion of the variance was associated with wild goat pressure (80% for high-pressure areas, 56% for low-pressure areas). A modified parabolic function was fit to express the relationship between Iberian wild goat pressure and impact on mosses. In conclusion, the im indicator was shown to be a useful tool to assess pressure due to Iberian wild goat. Therefore, im can help assess and manage Iberian wild goat populations and determine their sustainable levels.
Rain-fed granite rock pools in a National Park: extreme niches for protists Rain-fed granite rock pools are geological landforms with a worldwide distribution. However, their role as habitats for microorganisms has been barely explored. We carried out a detailed morphological inventory of the ciliated protists in the sediments of three granite rain-fed rock pools from a Spanish National Park. The ciliate seed bank in the rock pools comprised 54 morphospecies. The species number inferred for each pool by rarefaction analysis was similar to that observed by microscopy. The most representative species were small bacterivorous ciliates, although the distribution of ciliate groups was significantly different in each rock pool. Testate amoebae were also found to be rich in species. This study demonstrates the existence of a diverse ciliate community adapted to persist in these ephemeral and extreme rock pool habitats through species resistance structures, many of which have not been described previously. The presence of competitive species in dormant stages prevents local extinctions through a sequential excystation over time. Our results provide a benchmark for studying protist and microbial biodiversity within rain-fed granite rock pools, a unique habitat that merits bio-and geo-conservation.
Se describe un itinerario didáctico, ambiental, y cultural por la zona sur de Valdemorillo (Madrid). Su objetivo es promover la educación ambiental y ser útil a profesores y educadores de distintas disciplinas y niveles educativos. El artículo trata los conceptos de “itinerario didáctico”, “itinerario cultural”, “Patrimonio” y “turismo cultural”. Pretende poner de manifiesto la utilidad de los itinerarios para la educación formal y no formal. Propone una ruta que detalla los recursos geológicos, hidrologicos, los ecosistemas, la flora y la fauna. Al final sugiere unas actividades a desarrollar para educadores.
Palabras clave: Itinerario didáctico; itinerario cultural; Patrimonio Natural; Patrimonio Cultural; Valdemorillo; geología; ecología; fauna.
https://revistas.ucm.es/index.php/OBMD/article/view/62659/4564456548830
El geólogo Manuel García analiza en un curso de la UNED la relación entre la geomorfología del litoral y la forma de las olas
Abstract
1. Microorganisms play pivotal roles in aquatic ecosystems. Free‐living protists are the main components of the eukaryotic microbial communities at the base of freshwater ecosystems. Ciliate grazing channels a large proportion of organic matter into multicellular organisms. Surprisingly, ciliates and other microorganisms are neglected in global conservation schemes.
2. Interstitial ciliates were sampled in three sites of varying human pressure on the River Manzanares (La Pedriza National Park, Spain). Abundances of trophic groups and species were adjusted to a generalized linear model (GLM Poisson regression).
3. Ciliate communities were rich in species (74 morphotypes) and although traditional microscopy retrieved a high number of species that appeared only once or in low numbers, rarefaction analyses estimated much larger species richness. These results illustrate that rarefaction assays are a useful first step for exploring the extent of the ciliate cryptic diversity in freshwater ecosystems.
4. Benthic ciliate communities changed significantly, both spatially and at a short temporal scale. The fluctuating nature of the community was manifested by the presence of many ephemeral species at the same river site, revealing a complex and transient community structure. No
significant short‐term changes were observed in the physical–chemical properties. Therefore, even slight differences in the abiotic variables may cause rapid shifts of ciliate species.
5. Overall, human pressure had an effect on the interstitial (or benthic) ciliates that resulted in a reduction of species richness and their abundance.
KEYWORDS
benthos, biodiversity, ciliates, generalized linear models, human pressure, microbial habitats, protected areas, protists, river