Geobotanical Study of the Microforests of Juniperus oxycedrus subsp. badia in the Central and Southern Iberian Peninsula

Eusebio Cano,Ricardo Quinto-Canas,Ana Cano-Ortiz,Giovanni Spampinato,Alfonso Rodríguez Torres,Sara Del Río González,José Piñar Fuentes,Carmelo Musarella,Carlos Pinto Gomes

doi:10.3390/su11041111

Abstract

We have studied Juniperus oxycedrus L. subsp. badia (H.Gay) Debeaux in the central and southern Iberian Peninsula, where the macrobioclimate ranges from Mediterranean-pluviseasonal-oceanic to Mediterranean-pluviseasonal-continental, and the thermotype from the thermo- to the supramediterranean. The relevés were taken following the Braun-Blanquet phytosociological methodology. A statistical treatment was applied to establish a separation among Juniperus communities. To understand the presence of Juniperus communities in territories dominated by species in the Quercus genus, we applied Thornthwaite’s formula to calculate potential evapotranspiration. The general cluster analysis clearly distinguishes two groups of plant communities and separates the different associations in each group. All the plant communities growing on rocky crests and in extremely steep sloping areas are significantly influenced by the soil. The ombroclimatic index does not explain the presence of plant communities influenced by substrate, so we proposed a new ombroedaphoxeric index which explains the presence of Juniperus communities in territories with a thermotype between the thermo- and supramediterranean. The areas of distribution of Juniperus species are expanding due to the spread of rocky areas; this phenomenon causes an increase in edaphoxerophilous areas and a decrease in climatophilous ones. We propose four new plant associations, with updated structures and floristic compositions. Efficient conservation is possible in both the territories studied (Spain and Portugal) through the implementation of specific cross-border cooperation projects.

Highlights

There are around 60 woody species worldwide belonging to the genus Juniperus L. (Cupressaceae, gymnosperms), which is divided into three sections: J. sect
Adams et al [13] subsequently showed that the differentiation of J. deltoides from J. oxycedrus at a level that is consistent with the divergence of J. navicularis and J. macrocarpa from J. oxycedrus is based on leaf essential oil composition, RAPD (Random Amplification of Polymorphic DNA) fingerprinting and ITS (Internal Transcribed Spacer) sequence data
All the communities of J. oxycedrus subsp. badia share the fact that they are permanent communities with an edaphoxerophilous character, which is imposed by the rocky substrate caused by soil loss

Summary

Introduction

There are around 60 woody species worldwide belonging to the genus Juniperus L. (Cupressaceae, gymnosperms), which is divided into three sections: J. sect. The J. oxycedrus group is included within J. sect. Transtagana Franco) and J. deltoides R.P. Adams [syn.: J. oxycedrus L. subsp. Adams and collaborators [3,9] recently reported the distribution of J. deltoides for Italy, Croatia, Greece, Turkey, Azerbaijan, Bulgaria, Cyprus, and Israel, and established phytochemical differences with J. oxycedrus due to its higher limonene and lower alpha-pinene contents. Adams et al [13] subsequently showed that the differentiation of J. deltoides from J. oxycedrus at a level that is consistent with the divergence of J. navicularis and J. macrocarpa from J. oxycedrus is based on leaf essential oil composition, RAPD (Random Amplification of Polymorphic DNA) fingerprinting and ITS (Internal Transcribed Spacer) sequence data. Roma-Marzio et al [14] recently proposed an identification key for the Juniperus oxycedrus group based on a combined phytochemical and morphometric approach

Objectives

Methods

Results

Discussion

Conclusion