Luis Herrero

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.

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.

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.

The Duero Basin

The Spanish North Plateau or the Spanish Duero basin is located in the southern foothills of the Cantabrian Ranges in the north-western quadrant of the Iberian Peninsula. It was formed by the action of the Duero river and its tributaries on both the right and left. The climate can be considered continental between dry and humid. The vegetation in this territory is very varied, and several groups can be differentiated based on their structure and physiognomy, and based on the soil and climate variability in this area. These groups are: (1) Forest and woodlands dominated by Quercus rotundifolia, Quercus pyrenaica, Quercus faginea, Juniperus thurifera, Juniperus oxycedrus. (2) Riparian ecosystems formed by willows (Salix neotricha), poplars (Populus alba and Populus nigra), ashes (Fraxinus angustifolia), alders (Alnus glutinosa), elms (Ulmus minor) and shrubby willows (Salix salviifolia, Salix elaeagnos subsp. angustifolia). (3) Seral scrub, including spiny nanoshrublands dominated by Rosa sp. pl., Rubus sp. pl., broom communities formed by several species in the genera Cytisus and Genista, hygrophilous or non-hygrophilous heathlands, with a predominance of species from the genus Erica, secondary scrub communities dominated by Cistaceae and Lamiaceae or Thymus sp. pl. communities, and nitrophilous scrub dominated by Artemisia sp. and Santolina sp. (4) Gypsophilous vegetation. (5) Grasslands of a wide diversity starting with communities of Nardus stricta, and continuing with communities of Celtica gigantea, Poa bulbosa, Agrostis castellana, rushy pastures dominated by Juncus sp. pl., meadows, communities of Festuca elegans subsp. merinoi and Stipa sp. pl. (6) Herbaceous ruderal and assorted vegetation with widely differing communities of the Stellarietea mediae, with both a roadway ruderal character and also present in rain-fed and irrigated croplands and grasslands produced by human and animal action. (7) Aquatic vegetation, including riparian herbaceous communities, peat bogs, lakes and pools communities, reed communities, reed beds, megaforbic communities and pioneer annual and dwarf perennial isoetid communities on periodically flooded bare soils. (8) Salt marshes. (9) Rock vegetation. (10) Vegetation series.

Geranio subargentei-Carduetum carlinoidis, una nueva asociación de la clase Thlaspietea rotundifolii en los Picos de Europa

Se describe una nueva asociacion ( Geranio subargentei-Carduetum carlinoidis ) para la zona meridional del Parque Nacional de Picos de Europa. Estas comunidades orotempladas altoeslano-carrionesas se desarrollan sobre gleras finas de pequenas lascas de lutitas, facilmente erosionables y estan presididas por Carduus carlinoides .