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Geodiversity can be defined as the spatial variability of geo-elements. Its emergence as a research field is relatively recent, with a wide range of approaches and methods of evaluation and quantification already in use. The work described in this paper was carried out from a novel perspective. Firstly, the emphasis is specifically centred on geomorphological diversity. Secondly, mathematical ecology calculations are applied which tackle the problem on the basis of a larger number of diversity parameters. In addition, whereas most authors have focussed on mountainous and/or continental areas, for the first time a study of this type is applied to coastal landscapes. The analysis covers the full 459 km of volcanic coastline of the islands of Gran Canaria and La Palma (Canary Islands). These two oceanic islands were chosen for purposes of diversity comparison given their differing stages of geomorphic development. In accordance with an ad hoc geomorphological taxonomy, as developed in this study, 14 geomorphic groups and 42 subgroups were identified and quantified according to their presence [1] or absence [0] along the coastline. A cartographic-analytical method (coastline data-storing or CDS), based on the computation of binary information in the cartographic vector of the coastline, enabled calculation of the occurrence probability of these groups and subgroups. Both at local level (analyses of coastal morphoassemblages ) and general level, three components of geomorphological diversity (richness, evenness and dissimilarity) were estimated, through indices of richness (R), Shannon's entropy (H′) and Rao's quadratic entropy (Q). The data reveal that geomorphological coastal diversity is between 11.1% and 48.2% higher in Gran Canaria than in La Palma. The method was subjected to a fractal stress test through iterative mapping procedures to assess the effect of scale on the behaviour of the relative frequencies and indices. The variability that was obtained allowed the extraction of corrected values in the indices for La Palma (H′ c  = 1.88 ± 0.008 and Q c  = 0.183 ± 0.004) and Gran Canaria (H′ c  = 2.11 ± 0.019 and Q c  = 0.232 ± 0.003). A moving-window test was also applied as a rarefaction method to confirm the contrast in diversity in coasts of different size. The results enabled to advance hypotheses about the relation between coastal geomorphic diversity and geological age of islands. [ABSTRACT FROM AUTHOR]

Volcanic areas create spectacular landscapes that contain a great diversity of geoheritage. The study of this geoheritage enables us to inventory, characterise, protect and manage its geodiversity. The Canary Islands are a group of subtropical active volcanic oceanic islands with a great variety of magma types and eruption dynamics that give rise to a wide diversity of volcanic features and processes. The aim of this paper is to identify, for the first time, the diversity of volcanic geoheritage of the Canary Islands and to appraise the protection thereof. To this end, a geomorphological classification is proposed, taking into account the features and processes directly related to volcanism, such as those resulting from erosion and sedimentary processes. The main findings demonstrate that the volcanic geoheritage of the Canary Islands is extremely varied and that this geodiversity is safeguarded by regional, national and, international protection and management frameworks. Even so, and given the enormous pressure of coastal tourism on the coastlines of the islands, we believe that continuing efforts should be made to conserve and manage their volcanic and non-volcanic geoheritage, so that these places can continue to be enjoyed in the form of geotourism. [ABSTRACT FROM AUTHOR]

Oceanic islands are cradles of endemism, contributing substantially to global biodiversity. A similarity in magmatic origin translates into high global comparability of substrates of volcanic islands on the oceanic crust with, however, slightly chemically or physically differentiated petrography in some places. Phonolites are examples of rare localities with intermediate chemical characteristics between felsic and mafic and with diverse textures. They contribute to habitat heterogeneity and offer specific growth conditions in a significantly different matrix of basaltic substrates. The explicit contribution of geodiversity to island biodiversity has been little studied, despite growing evidence of its importance on continents. On the island of La Palma, Canary Islands, isolated phonolitic rocks are conspicuous due to their light colour and specific shape. Although these outcrops only cover small areas, their unique form and composition increase within-island geodiversity. To investigate how this affects biodiversity on La Palma, we sampled all vascular plant species in 120 plots on four sets of paired sites in order to test if plant diversity and performance is enhanced on phonolitic rocks compared to basaltic rocks. We recorded species number and abundance as well as individual plant height and diameter as proxies for aboveground resource allocation and tested for differences in vegetation cover and species composition between the bedrock types. We found higher species richness and abundance on phonolites than neighbouring basaltic substrates, and individuals of the same species were larger (in height and diameter) on phonolites compared to neighbouring basalt. An endemic woody species with two distinct varieties even appears almost exclusively on the small surfaces of phonolitic rock. Despite extremely limited spatial extent, phonolitic rocks can play an important role in plant biodiversity on islands. [ABSTRACT FROM AUTHOR]

The concept of geodiversity is becoming more widely used every year, beyond its contribution to the development of geotourism. It is estimated that geodiversity is as important as biodiversity in the functioning of Earth's natural ecosystems. Therefore, an important problem is to recognize the possibilities on integrating geodiversity in geographic education, both formal and informal. The main aim of the study is to identify the subject of educating godiversity, included in the core curricula in Spain and Canary Islands and to identify the forms, didactic tools and methods of geodiversity education existed in selected national, natural parks and geoparks of Canary Islands. The study has shown that the application of geodiversity in educational practice is still unsettled. [ABSTRACT FROM AUTHOR]