Ángel Penas

Recent trends in mean maximum and minimum air temperatures over Spain (1961–2006)

This study analyzes the mean maximum and minimum temperature trends on a monthly, seasonal, and annual timescale by applying various statistical tools to data from 476 Spanish weather stations during the period between 1961 and 2006. The magnitude of the trends was derived from the slopes of the regression lines using the least squares method, and the nonparametric Mann–Kendall test was used to determine the statistical significance of the trends. Temperature significantly increased in over 60% of the country in March, June, spring, and summer in the case of maximum temperatures and in March, May, June, August, spring, and summer for minimum temperatures. At the annual resolution, temperatures significantly increased in over 90% of Spain with a rise of around 0.3°C/decade. The maximum temperature increased at a higher rate than the minimum temperature from midsummer to early winter as well as in winter, spring, and summer and also on an annual basis.

Links between teleconnection patterns and mean temperature in Spain

This work describes the relationships between Spanish temperature and four teleconnection patterns with influence on the Iberian Peninsula on monthly, seasonal and annual time scales, using data from 144 meteorological stations. Partial correlation analyses were carried out using Spearman test, and spatial distribution maps of the correlation coefficients were produced with geostatistical interpolation techniques. We regionalize the study area based on homogeneous areas containing weather stations with a similar response of temperatures to the same patterns. The links between the temperature and the patterns are mainly positive; only the correlations with Western Mediterranean Oscillation (WeMO) in the north and west are negative, indicating that WeMO plays an opposed role in temperature behaviour in Spain. In general terms, the four modes exert considerable influence on temperature in February, May and September. The East Atlantic (EA) is the pattern with the strongest influence on temperature in Spain—mainly in the north—except in June. Generally, on the seasonal and annual scales, large significant areas were only observed for the EA. EA and WeMO best account for the mean temperature on the Mediterranean fringe and in northern Spain, while EA and North Atlantic Oscillation largely explain the temperature in the rest of Spain.

Incorporating bioclimatic and biogeographic data in the construction of species distribution models in order to prioritize searches for new populations of threatened flora

The aim of this study was to analyse the usefulness of incorporating bioclimatic and biogeographic data into digital species prediction and modelling tools in order to identify potential habitats of rare or endangered flora taxa. Species distribution models (SDMs) were obtained using the Maximum entropy algorithm. Habitat suitability maps were based on sites of known occurrence of studied species. The study showed that highly reliable habitat prediction models can be obtained through the inclusion of bioclimatic and biogeographic maps when modelling these species. The resultant SDMs are able to fit the search area more closely to the characteristics of the species, excluding the percentage of highly suitable areas that are located far from the known distribution of the taxon, where the probability of finding the plant is low. Therefore, it is possible to overcome one of the most commonly encountered problems in the construction of rare or threatened flora taxa SDMs, derived from the low number of initial citations. The resulting SDMs and the vegetation map enable prioritization of the search for new populations and optimization of the economic and human resources used in the collection of field data.

Contribution to the phytosociological survey of the primary forests in the NE of Rio Grande do Sul (Brazil)

Abstract We present the results of a phytosociological survey of the primary forests of different areas in the NE of Rio Grande do Sul (Brazil). The study combines the Braun‐Blanquet’s methodology of collecting phytosociological data with a technique of numerical classification (Average Linkage Clustering based on Euclidean distance). Five associations, five sub‐associations, three alliances, two orders and one phytosociological class are proposed in this paper on the basis of the cluster analysis of 59 phytosociological relevés, and of floristic, biogeographical, bioclimatic, edaphic, and physiognomic data from previous phytosociological studies of Brazil’s forests.

Recent climatic trends in Castilla and León (Spain) and its possible influence on the potential natural vegetation

Abstract Precipitation and mean temperature trends at monthly, seasonal and annual time scale for Castilla and León during the period 1961–2004 were analysed in the present study. The main aims of this paper were to find out if these tendencies differ from those pointed out for this region in a previous research for the period 1961–1997 and to establish, based on bioclimatic models, possible changes on the potential natural vegetation of this territory if these trends do not change in future. Magnitude of trends was derived from the slopes of the regression lines while the statistical significance was determined by the Mann—Kendall test. Magnitude and sign of rainfall and temperature trends over the last four decades have been essentially the same than those concerning to the period 1961–1997. It can be concluded that if these trends keep in future areas with temperate climate could increase in this region. In this situation, deciduous forests could extend their distribution limits, thus replacing some semi—deciduous and evergreen ones.

Bioclimatology of the Iberian Peninsula and the Balearic Islands

According to criteria and proposals of S. Rivas-Martinez, S. Rivas-Saenz and A. Penas (Glob Geobot 1(1):1–634, 2011a) with which they established a world bioclimatic classification system, two macrobioclimates (Temperate and Mediterranean), eight bioclimates (temperate hyperoceanic, temperate oceanic, temperate xeric, mediterranean pluviseasonal-oceanic, mediterranean pluviseasonal-continental, mediterranean xeric-oceanic and mediterranean desertic-oceanic), two bioclimatic variants (steppic and submediterranean), 11 thermotypes (thermotemperate, mesotemperate, supratemperate, orotemperate, cryorotemperate, inframediterraean, thermomediterranean, mesomediterranean, supramediterranean, oromediterranean and cryoromediterraean) and seven ombrotypes (arid, semiarid, dry, subhumid, humid, hyperhumid and ultrahyperhumid) are recognized in the Iberian Peninsula and Balearic Islands. In addition to this, six types of continentality (euhyperoceanic, subhyperoceanic, semihyperoceanic, euoceanic, semicontinental and subcontinental) are also recognized. Furthermore, relationships between potential natural vegetation (sigmeta, geosigmeta, permasigmata, minorisigmeta and geopermasigmeta) and the bioclimatic units existing in the Iberian Peninsula and Balearic Islands are set.

Biogeographic Units of the Iberian Peninsula and Baelaric Islands to District Level. A Concise Synopsis

The following biogeographic units for the Iberian Peninsula and Balearic Islands have been established according to the conceptual geobotanical proposals of Rivas-Martinez et al. (Parte I. Itinera Geobotanica 17:5–436, 2007; Parte II. Itinera Geobotanica 18 (1):5–424, 2011a; Glob Geobot 1(1):1–634, 2011b; Int J Geobot Res 1(1):21–40, 2011c and Int J Geobot Res 4(1):1–64, 2014): one kingdom (Holartic), two regions (Eurosiberian, Mediterranean), eight provinces, 16 subprovinces, 49 sectors and 264 districts. The potential natural vegetation: climatophilous, climato-temporihygrophilous, xerophilous, hygrophilous sigmetum or geopermasigmetum (series and geopermaseries) are shown for each province and sector. We also point out some of their specific features. Biogeographic maps up to district level are shown.

Valuation methods in vegetation and its use in land management.

Abstract The main methods for valuating vegetation proposed by different authors over the last three decades are summarized and discussed in this paper. As a result of this fact a new index for calculating the global conservation interest of the vegetation in a place or site is also proposed in this study. The index, based on the Cadiñanos & Meazas proposals, includes new criteria and synphytosociological concepts and can be a very useful tool to be applied in land management and nature conservation studies.

Nuevas comunidades vegetales de la Cordillera Cantábrica (León, España)

Se describen dos nuevas asociaciones: Aconitetum neapolitano-vulgaris y Geranio subargenti-Nardetum strictae , asi como una nueva subasociacion: Oenantho crocatae-Phalaridetum arundinaceae glycerietosum fluitantis , propias de la Cordillera cantabrica (NE de Leon, Espana). Tambien se da a conocer en la subprovincia Orocantabrica la existencia de la asociacion turbicola atlantica oceanica Anagallido tenellae-Juncetum bulbosi Br.-Bl. 1967.

Potential impacts of climate change on habitat suitability of Fagus sylvatica L. forests in spain

Abstract Fagus sylvatica forests are considered to be of Community interest according to Directive 92/43/EEC. Climate change predictions for Spain point to a warming scenario, coupled with decreasing rainfall, which may have an impact on their future distribution particularly at the extremes of its distribution area. Species distribution models incorporating bioclimatic, topographic and phytogeographic variables were used as predictors to assess their habitat suitability under current conditions and a climate change projection. Ten single models were generated and an ensemble-forecasting model was subsequently built by computing a consensus of single-model projections. The results revealed that ombrothermic indices are the main factors controlling the distribution of Spanish beech forests. They are highly vulnerable to climate change and could suffer a decline in their habitat suitability if climate trends observed are maintained in the future. The least favoured areas for them will be located close to the limit between the Temperate and Mediterranean climates, where they could suffer a loss of habitat suitability. Conversely, suitable new areas could be found mainly in western areas of the Cantabrian Range and in the Central Pyrenees.