Climate and vegetation at the Eurosiberian‐Mediterranean boundary in the Iberian Peninsula

Abstract

The Northern Iberian Peninsula is dominated by various types of vegetation from deciduous oak and ash to evergreen oak woodlands. A recent vegetation map of Spain portrays vegetation series which are characterized in terms of their phytogeographic region or bioclimatic (altitudinal) belt. The aim of this paper is to determine whether the areas comprised by both phytogeographic regions (Eurosiberian and Mediterranean) in the study area, as established from the phytogeographic characterization of the vegetation, can be discriminated by climatic variables using multivariate methods, and to compare these with other conventional approaches.In addition, bioclimatic (altitudinal) belts and the main vegetation types were tested for discrimination by climatic variables. Conventional climatic criteria as well as discriminant and principal component analysis were applied to climatic data from 205 meteorological stations for which vegetation information had been taken from the vegetation map. Conventional criteria are good predictors of the phytogeographic division (Mediterranean and Eurosiberian regions) in the study area. Results were improved by multiple discriminant analysis based on climatic data of the dry period of the year (June to September). Both regions in the study area can be predicted with over 95 % accuracy. Using the same multivariate procedure and temperature data the bioclimatic (altitudinal) belts of the study area can be predicted with over 90 % accuracy. The main vegetation groups of the study area can also be predicted with over 80 % accuracy. Ordination analysis supported the results of the discriminant analysis. Empirical models have been generated to predict the phytogeographic-and belt character of any station in the area. The significance of the various periods of the year for discriminating regions and belts is evaluated. The responsiveness to climatic events during the year may be region specific. This study confirms the strong relationship between climate and vegetation in the Northern Iberian Peninsula, particularly regarding the Eurosiberian-Mediterranean boundary.

Shrub fuel characteristics estimated from overstory variables in NW Spain pine stands

“…Only these regions were selected in order to lessen the variability of the climate conditions and floristic composition of the understory. Both Asturias and Galicia are included in the Eurosiberian phytogeographic region, roughly characterized by two months of dryness (precipitation, mm < 2 Â temperature,°C) (Moreno et al, 1990).…”

Present and future extension of the Iberian submediterranean territories as determined from the distribution of marcescent oaks

“…Between the genuinely Mediterranean and temperate regions, there is a band where both regions become diluted and mix (see Pineda 1985 andMoreno et al 1990 for information on the Iberian Peninsula, Blasi et al 1999 regarding Italy andHrsak 2003 regarding Croatia). Such areas are generally termed submediterranean.…”

Soil water regime through contrasting pasture communities in a Submediterranean landscape

“…Moreover, the transitional aspect of water shortening and plant responses through the Submediterranean area has not been analysed, although soil water regime and water use by plants have been assumed to be the main causes for vegetation shifts (Izco et al, 1985;Moreno et al, 1990;Porporato et al, 2001). Also differences in soil moisture dynamics are among the principal reasons for the existence of particular vegetation types .…”