Forest vegetation on sacred sites of the Tangier Peninsula (NW Morocco) – discussed in a SW-Mediterranean context

Abstract

Forest stands on sacred sites can document climax or preclimax vegetation. However, little is known about the potential climax character of sacred sites in Morocco. We studied the vegetation of Muslim sacred sites and graveyards in rural regions of the Tangier Peninsula in Northwest Morocco. Sacred sites were chosen according to a pre-stratifi ed random sampling method, taking climatic and edaphic patterns into account. In tree stands of 68 sacred sites 140 phytosociological relevés were sampled and classifi ed. In an attempt to evaluate their degree of preservation, the best preserved holy forests were compared with reference data of similar forest communities, recorded mainly on non-sacred sites in southern Spain and Portugal, and northern Morocco and Algeria. The forested vegetation of sacred sites shows a great variety. Abiotic factors, such as substrate and bioclimate, and human interventions (grazing, fi re, a.o.) were found to be important differentiating factors. Besides well-conserved forests, a broad spectrum of degradation stages was documented. Most stands still shelter the original tree species combination, but vertical structure and fl oristic composition of the herb layer are strongly modifi ed. Processes related to anthropo-zoogenic pressure, like therophytization, ruderalisation and overaging of the tree layer occur despite religious taboos. Near-natural holy forests belong to various subtypes of the Teucrio baetici-Quercetum suberis and the Rusco hypophylli-Quercetum cocciferae. In comparison to forests on non-sacred sites, these holy forests are very well preserved, as is indicated by the presence of strict forest species of the Quercetalia ilicis and the Querco-Oleion sylvestris, by transgressives of the Quercetalia pubescentis, and by a high constancy and abundance of ombro-and mesophilous taxa. Moreover, the comparison of phytosociological data from Morocco and Spain indicated an Ibero-Mauretanian distribution of several Quercus suber communities. In conclusion, sacred groves often seem to represent the potential natural vegetation. Exceptions are sacred groves with Wild Olive, which occur in an ecoregion where a thermomediterranean Quercus suber forest is considered to be the climax.

Sacred sites in north‐western Morocco – naturalness of their vegetation and conservation value for vulnerable plant species

“…Previous studies argued that sacred sites in northern Morocco preserve unique thermomediterranean forest types such as Rusco hypophylli‐Quercetum cocciferae and well‐preserved stands of more widespread forest types such as Teucrio baetici‐Quercetum suberis (Sauvage ; Benabid ; Quézel & Barbero ). This was confirmed by a recent vegetation analysis from north‐western Morocco, which, however, also described for the first time several stages of degradation of these forests (Frosch & Deil ). Until now the percentage of little disturbed forests on sacred sites in Morocco was unknown, except the preliminary observations of Taiqui et al.…”

“…For three geological‐climatic strata (A, B, C), two corresponding landscape sections were chosen randomly. One landscape section was chosen randomly in a schist/flysch region (D), and one in a transitional area between sandstone and schist/flysch (E) (see Frosch & Deil , Figs. and for methodological steps in data sampling).…”

“…sylvestris) (Valdés et al 2002). Details of the bioclimatic niches of the dominating tree species are presented by Frosch & Deil (2011, Fig. 3).…”

“…Therefore, they have been included into the concept of sacred sites in this study. In northern Morocco, some rare thermomediterranean forest types and very well-preserved stands of more wide-spread forest types are conserved almost exclusively at sacred sites (Sauvage 1961;Benabid 1984;Quézel & Médail 2003;Frosch & Deil 2011). However, the exemplary study of two sacred sites in northern Morocco by Deil et al (2008) revealed a mosaic character of the vegetation due to pronounced human impact.…”

“…This preliminary and non-quantified impression was confirmed by an inventory of 575 sacred sites in the province of Larache (NW Morocco) by Taiqui et al (2009) who stated 178 sites with forests, 14 with maquis and 383 without vegetation. As a result of overgrazing and nitrification, sacred groves seem to be often degraded, overaged or reduced to tree groups or a single tree, and processes like the replacement of woody underbrush and perennial forest herbs by ruderals and annual species (therophytisation, ruderalisation) take place (Frosch 2010;Frosch & Deil 2011).…”