Person: Pintado Valverde, Ana
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First Name
Ana
Last Name
Pintado Valverde
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Farmacia
Department
Farmacología, Farmacognosia y Botánica
Area
Botánica
Identifiers
13 results
Search Results
Now showing 1 - 10 of 13
Item Recent Warming and Cooling in the Antarctic Peninsula Region has Rapid and Large Effects on Lichen Vegetation(Scientific Reports, 2017) Navarro, Francisco; Ramos, Miguel; Pablo, Miguel Angel De; Blanquer, José Manuel; Valladares, Fernando; García Sancho, Leopoldo; Pintado Valverde, Ana; Raggio Quílez, José; Green, Thomas George AllanThe Antarctic Peninsula has had a globally large increase in mean annual temperature from the 1951 to 1998 followed by a decline that still continues. The challenge is now to unveil whether these recent, complex and somewhat unexpected climatic changes are biologically relevant. We were able to do this by determining the growth of six lichen species on recently deglaciated surfaces over the last 24 years. Between 1991 and 2002, when mean summer temperature (MST) rose by 0.42 °C, five of the six species responded with increased growth. MST declined by 0.58 °C between 2002 and 2015 with most species showing a fall in growth rate and two of which showed a collapse with the loss of large individuals due to a combination of increased snow fall and longer snow cover duration. Increased precipitation can, counter-intuitively, have major negative effects when it falls as snow at cooler temperatures. The recent Antarctic cooling is having easily detectable and deleterious impacts on slow growing and highly stress-tolerant crustose lichens, which are comparable in extent and dynamics, and reverses the gains observed over the previous decades of exceptional warming.Item Antarctic Studies Show Lichens to be Excellent Biomonitors of Climate Change(Diversity, 2019) García Sancho, Leopoldo; Pintado Valverde, Ana; Green, Thomas George AllanLichens have been used as biomonitors for multiple purposes. They are well-known as air pollution indicators around urban and industrial centers. More recently, several attempts have been made to use lichens as monitors of climate change especially in alpine and polar regions. In this paper, we review the value of saxicolous lichens for monitoring environmental changes in Antarctic regions. The pristine Antarctica offers a unique opportunity to study the effects of climate change along a latitudinal gradient that extends between 62° and 87° S. Both lichen species diversity and thallus growth rate seem to show significant correlations to mean annual temperature for gradients across the continent as well as to short time climate oscillation in the Antarctic Peninsula. Competition interactions appear to be small so that individual thalli develop in balance with environmental conditions and, as a result, can indicate the trends in productivity for discrete time intervals over long periods of time.Item Whole Lichen Thalli Survive Exposure to Space Conditions: Results of Lithopanspermia Experiment with Aspicilia fruticulosa(Astrobiology, 2011) Raggio Quílez, José; Pintado Valverde, Ana; Ascaso, C.; De La Torre, R.; De Los Ríos, A.; Wierzchos, J.; Horneck, G.; García Sancho, LeopoldoThe Lithopanspermia space experiment was launched in 2007 with the European Biopan facility for a 10-day spaceflight on board a Russian Foton retrievable satellite. Lithopanspermia included for the first time the vagrant lichen species Aspicilia fruticulosa from Guadalajara steppic highlands (Central Spain), as well as other lichen species. During spaceflight, the samples were exposed to selected space conditions, that is, the space vacuum, cosmic radiation, and different spectral ranges of solar radiation (λ ≥ 110, ≥200, ≥290, or ≥400 nm, respectively). After retrieval, the algal and fungal metabolic integrity of the samples were evaluated in terms of chlorophyll a fluorescence, ultrastructure, and CO2 exchange rates. Whereas the space vacuum and cosmic radiation did not impair the metabolic activity of the lichens, solar electromagnetic radiation, especially in the wavelength range between 100 and 200 nm, caused reduced chlorophyll a yield fluorescence; however, there was a complete recovery after 72 h of reactivation. All samples showed positive rates of net photosynthesis and dark respiration in the gas exchange experiment. Although the ultrastructure of all flight samples showed some probable stress-induced changes (such as the presence of electron-dense bodies in cytoplasmic vacuoles and between the chloroplast thylakoids in photobiont cells as well as in cytoplasmic vacuoles of the mycobiont cells), we concluded that A. fruticulosa was capable of repairing all space-induced damage. Due to size limitations within the Lithopanspermia hardware, the possibility for replication on the sun-exposed samples was limited, and these first results on the resistance of the lichen symbiosis A. fruticulosa to space conditions and, in particular, on the spectral effectiveness of solar extraterrestrial radiation must be considered preliminary. Further testing in space and under space-simulated conditions will be required. Results of this study indicate that the quest to discern the limits of lichen symbiosis resistance to extreme environmental conditions remains openItem Metabolic activity duration can be effectively predicted from macroclimatic data for biological soil crust habitats across Europe(Geoderma, 2017) Raggio Quílez, José; Green, Thomas George Allan; García Sancho, Leopoldo; Pintado Valverde, Ana; Colesie, Claudia; Weber, Bettina; Büdel, BurkhardBiological soil crusts (BSC) perform several important environmental functions such as soil erosion prevention, soil nutrient enrichment through photosynthesis and nitrogen fixation, and are receiving growing interest due to their importance in some changing habitats with soils under degradation risk. Primary producers within BSC (cyanobacteria, lichens, algae and bryophytes) are all poikilohydric and active only when wet, meaning that knowledge of the period of metabolic activity is essential to understand growth and adaptation to environment. Finding links with macroclimatic factors would allow not only prediction of activity but also the effects of any climate change over these communities. Metabolic activity and microclimate of BSC at four sites across Europe with different soils from semi-arid (Almeria, SE Spain) to alpine (Austria) was monitored during one year using a chlorophyll fluorometer. Local climatic data were also recorded. Mean monthly activity of crust within each site were strongly linked irrespective of crust type whilst, using the data from all sites, highly significant linear relationships (mean monthly values) were found for activity with incident light, air temperature and air relative humidity, and a nonlinear response to rainfall saturating at about 40 mm per month. Air relative humidity and air temperature were the best predictors of metabolic activity duration. The links observed are all highly significant allowing climate data to be used to model activity and to gain inferences about the effects of climate change over BSC communities, soil structure and fertility. Linear relationships mean that small changes in the environment will not produce massive alterations in activity. BSC also appear to behave as a single functional group, which is helpful when proposing general management policies for soil ecosystems protection.Item Summer activity patterns for a moss and lichen in the maritime Antarctic with respect to altitude(Polar Biology, 2021) Schroeter, Burkhard; Green, Thomas George Allan; Pintado Valverde, Ana; Türk, Roman; García Sancho, LeopoldoThere is considerable scientific interest as to how terrestrial biodiversity in Antarctica might respond, or be expected to respond, to climate change. The two species of vascular plant confined to the Antarctic Peninsula have shown clear gains in density and range extension. However, little information exists for the dominant components of the flora, lichens and bryophytes. One approach has been to look at change in biodiversity using altitude as a proxy for temperature change and previous results for Livingston Island suggested that temperature was the controlling factor. We have extended this study at the same site by using chlorophyll fluorometers to monitor activity and microclimate of the lichen, Usnea aurantiaco-atra, and the moss, Hymenoloma crispulum. We confirmed the same lapse rate in temperature but show that changes in water relations with altitude is probably the main driver. There were differences in water source with U. aurantiaco-atra benefitting from water droplet harvesting and the species performed substantially better at the summit. In contrast, activity duration, chlorophyll fluorescence and photosynthetic modelling all show desiccation to have a large negative impact on the species at the lowest site. We conclude that water relations are the main drivers of biodiversity change along the altitudinal gradient with nutrients, not measured here, as another possible contributor.Item Photosynthetic rate and thallus size are not related in alpine yellow-green Rhizocarpon crustose lichens: Implications for lichenometry and growth(Geomorphology, 2018) Raggio Quílez, José; Green, Thomas George Allan; García Sancho, Leopoldo; Pintado Valverde, AnaLichenometry, first proposed at the beginning of the XXth century, is a technique that uses growth rates of saxicolous crustose lichens to date exposed surfaces over an age range of 500 years from present. Despite of the wide use of the methodology, it has been strongly criticized by several authors who consider that biological aspects involved in growth rates of lichens used are not sufficiently considered and that this will contribute to uncertainty in the final surface dating. The assumption, important for direct lichenometric measurements, that crustose lichens have constant growth rates through all their life span, is controversial, with some works pointing to a change in growth rate with thallus size in yellow-green Rhizocarpon sp. samples, the most widely lichens used for surface dating. This change in growth rate with size would contribute to inaccuracy in dating. In this work, we contribute to the discussion with a novel approach in which we measure several physiological parameters linked to carbon gain in 42 Rhizocarpon sp. samples of different sizes collected in the same locality. We found no significant relationship between thallus photosynthetic rate and thallus size indicating that possible growth rate variations over Rhizocarpon life span are not linked to carbon gain. The experiment performed provides a new data set to include in lichenometric modelling with the aim to obtain a better understanding of crustose lichens biology before attempting more feasible and accurate surface dating strategies. Measurements of length of activity periods and carbon allocation in Rhizocarpon are recommended to achieve future improvements in this direction.Item Climate change leads to higher NPP at the end of the century in the Antarctic Tundra: Response patterns through the lens of lichens(Science of the Total Environment, 2022) Beltrán Sanz, Nuria; Raggio Quilez, José; Gonzalez, Sergi; Dal Grande, Francesco; Prost, Stefan; Pintado Valverde, Ana; Green, Allan; García Sancho, LeopoldoPoikilohydric autotrophs are the main colonizers of the permanent ice-free areas in the Antarctic tundra biome. Global climate warming and the small human footprint in this ecosystem make it especially vulnerable to abrupt changes. Elucidating the effects of climate change on the Antarctic ecosystem is challenging because it mainly comprises poikilohydric species, which are greatly influenced by microtopographic factors. In the present study, we investigated the potential effects of climate change on the metabolic activity and net primary photosynthesis (NPP) in the widespread lichen species Usnea aurantiaco-atra. Long-term monitoring of chlorophyll a fluorescence in the field was combined with photosynthetic performance measurements in laboratory experiments in order to establish the daily response patterns under biotic and abiotic factors at micro- and macro-scales. Our findings suggest that macroclimate is a poor predictor of NPP, thereby indicating that microclimate is the main driver due to the strong effects of microtopographic factors on cryptogams. Metabolic activity is also crucial for estimating the NPP, which is highly dependent on the type, distribution, and duration of the hydration sources available throughout the year. Under RCP 4.5 and RCP 8.5, metabolic activity will increase slightly compared with that at present due to the increased precipitation events predicted in MIROC5. Temperature is highlighted as the main driver for NPP projections, and thus climate warming will lead to an average increase in NPP of 167–171% at the end of the century. However, small changes in other drivers such as light and relative humidity may strongly modify the metabolic activity patterns of poikilohydric autotrophs, and thus their NPP. Species with similar physiological response ranges to the species investigated in the present study are expected to behave in a similar manner provided that liquid water is available.Item High nitrogen contribution by Gunnera magellanica and nitrogen transfer by mycorrhizas drive an extraordinarily fast primary succession in sub‐Antarctic Chile(New Phytologist, 2019) Benavent González, Alberto; Raggio Quílez, José; Villagra, Johana ; Pintado Valverde, Ana; Blanquer, José Manuel ; Rozzi, Ricardo ; Green, Thomas George Allan; García Sancho, LeopoldoChronosequences at the forefront of retreating glaciers provide information about colonization rates of bare surfaces. In the northern hemisphere, forest development can take centuries, with rates often limited by low nutrient availability. By contrast, in front of the retreating Pia Glacier (Tierra del Fuego, Chile), a Nothofagus forest is in place after only 34 yr of development, while total soil nitrogen (N) increased from near zero to 1.5%, suggesting a strong input of this nutrient. We measured N-fixation rates, carbon fluxes, leaf N and phosphorus contents and leaf δ15N in the dominant plants, including the herb Gunnera magellanica, which is endosymbiotically associated with a cyanobacterium, in order to investigate the role of N-fixing and mycorrhizal symbionts in N-budgets during successional transition. G. magellanica presented some of the highest nitrogenase activities yet reported (potential maximal contribution of 300 kg N ha−1 yr−1). Foliar δ15N results support the framework of a highly efficient N-uptake and transfer system based on mycorrhizas, with c. 80% of N taken up by the mycorrhizas potentially transferred to the host plant. Our results suggest the symbiosis of G. magellanica with cyanobacteria, and trees and shrubs with mycorrhizas, to be the key processes driving this rapid successioncyanobacteriaItem Environmental determinants of biocrust carbon fluxes across Europe: possibilities for a functional type approach(Plant and Soil, 2018) Büdel, Burkhard; Raggio Quílez, José; Green, Thomas George Allan; Pintado Valverde, Ana; García Sancho, LeopoldoBackground and aims Due to the well-known importance of biocrusts for several ecosystem properties linked to soil functionality, we aim to go deeper into the physiological performance of biocrusts components. Possible functional convergences in the physiology of biocrust constituents would facilitate the understanding of both species and genus distributional patterns and improve the possibility of modelling their response to climate change. Methods We measured gas exchange in the laboratory under controlled conditions of lichen- and moss-dominated biocrusts from four environmentally different locations in Europe. Field data were used to determine the natural hydration sources that drive metabolic activity of biocrusts. Results Our results show different activity drivers at the four sites. Within site analyses showed similar C fixation for the different crust types in the three sites without hydric stress whilst light use related parameters and respiration at 15 °C were similar in the between sites analyses. There were significant differences in water relations between the biocrusts types, with moss-dominated crusts showing higher maximum and optimum water contents. Conclusions The functional type approach for biocrusts can be justified from a physiological perspective when similar values are found in the within and between site analyses, the latter indicating habitat independent adaptation patterns. Our multi-site analyses for biocrusts functional performance provide comparisons of C fluxes and water relations in the plant-soil interface that will help to understand the adaptation ability of these communities to possible environmental changes.Item Anatomical, morphological and ecophysiological strategies in Placopsis pycnotheca (lichenized fungi, Ascomycota) allowing rapid colonization of recently deglaciated soils(Flora, 2011) Ríos, Asunción De los; Raggio Quílez, José; Pérez-Ortega, Sergio; Vivas, Mercedes; Pintado Valverde, Ana; Green, Thomas George Allan; Ascaso, Carmen; García Sancho, LeopoldoThe green algal lichen Placopsis pycnotheca was identified at Pia and Marinelli glaciers (Isla Grande of Tierra de Fuego, Chile) as a primary colonizer of bare soil in areas close to the front of the glacier or around small ponds created after glacier retreatment. Electron microscopy study showed that P. pycnotheca formed a thick hypothallus within which hyphae and their extracellular polymeric substances bind numerous soil particles. This structure augments water holding and soil stabilization capacities and constitutes an early stage in soil crust development. In addition, numerous cephalodia are formed within the hypothallus and subsequently develop upwards towards the thallus surface, sometimes before the formation of squamules with green algae. These anatomical and morphological strategies together with physiological properties such as the long photosynthetic activity period (measured in the laboratory) help explain its pioneering role as a colonizer and its apparently high growth rate.