Biogeography, ecology and history of Mediterranean Quercus ilex ecosystems

Abstract

Quercus ilex sensu lato plays an important role in Western Mediterranean ecosystems, but is poorly developed in the Eastern Mediterranean where it is often replaced by Quercus calliprinos.The occurrence of Quercus ilex in the different bioclimates and their thermic subdivisions is presented on a small scale. Under certain geographical and ecological conditions, Quercus ilex participates in the organization of vegetation ecosystems from the meso-Mediterranean to the oro-Mediterranean altitudinal zones.Quercus ilex imposes microclimatic constraints on its associated species; it thus organizes an original understory vegetation structure (ethoh)gical groups) which will be defined in this study.One of the reasons for the success of Quercus ilex stems from its remarkable resistance to ecological constraints. A broad synthetic presentation of foliar area index variations in relation to different types of stress serve as a basis for an explanation of the sclerophyllous model in the Mediterranean region.Finally, historical factors are outlined as being critical characteristics in the determination of the present organization and spatial structure of Quercus ilex ecosystems. These considerations will be analyzed from a paleobioclimatical point of view, including data related to human pressure. Distribution and biogeography of sclerophyllous oaks (Fig.

Environmental Drivers of Holocene Forest Development in the Middle Atlas, Morocco

“…This sclerophyll tree occurs across an enormous altitudinal range in Morocco (300-2,800 m.a.s.l.) and is remarkable in its ecological plasticity (Barbero et al, 1992). It is tolerant of drought and high continentality, and is abundant across the meso-to montane-mediterranean vegetation levels in subhumid and semiarid bioclimates (Peguero-Pina et al, 2014).…”

“…Colored shading highlights changes in inferred lake level and human impact on the catchment (Zielhofer et al, 2017a). morphotype is debated, it clearly represents a distinct ecotype with enhanced drought resistant functional traits compared with Q. ilex (Barbero et al, 1992). Evergreen Quercus pollen reaches maximum percentages and PARs in PAZ-2, indicating an important degree of drought stress under warm, summer-dry conditions in the Early Holocene.…”

Distribution of evergreen broad-leaved woody species in Insubria in relation to bedrock and precipitation

“…This explains the restriction of Q. ilex at its northern fringe of distribution to drier sites with calcareous soils, whereas in the core area of distribution no clear soil preference is apparent (S. Sabate, pers com.). The same pattern is shown by Viburnum tinus which is often associated with Q. ilex (Barbero et al 1992). It shares the same ecological preferences for dry, calcareous sites within Insubria, in spite of its edaphic indifference in eumediterranean areas of its distribution (Torres et al 2002).…”

“…data). In the entire region, this relatively slow growing sclerophyllous species profits on shallow calcareous soils from reduced competition from deciduous species (Larcher 1979;Barbero et al 1992;Brullo and Guarino 1998;Mitrakos 1980;Kollmann and Pflugshaupt 2005), or from faster growing evergreen broad-leaved (laurophyllous) species. This explains the restriction of Q. ilex at its northern fringe of distribution to drier sites with calcareous soils, whereas in the core area of distribution no clear soil preference is apparent (S. Sabate, pers com.).…”

Foliage maturity of Quercus ilex affects the larval development of a Croatian coastal population of Lymantria dispar (Lepidoptera: Erebidae)

“…While in the coastal region an evergreen broadleaved xerophyte, the holm oak (Q. ilex L.), and deciduous xerophyte downy oak (Q. pubescens Willd.) are the dominant tree species [17][18][19][20]. All of these tree species have suffered total defoliation by gypsy moth feeding during mass outbreaks in the past [21].…”