Journal of African Earth Sciences 99 (2014) 735–742
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Geotourism, Medical Geology and local development: Cape Verde case study F. Rocha ⇑, E. Ferreira da Silva Geobiotec Research Centre, Geosciences Dept., Univ. Aveiro, Portugal
a r t i c l e
i n f o
Article history: Received 22 July 2013 Received in revised form 12 April 2014 Accepted 15 April 2014 Available online 5 May 2014 Keywords: Cape Verde Geotourism Geomedicine
a b s t r a c t Geotourism and Geoparks in particular are real opportunities to rural developments promoting the rate decline of unemployment and emigration through engaging the local communities in geopark activities and tourism marketing in the form of adventure tourism, ecotourism, rural tourism and health geotourism. Geotourism is closely linked with Medical Geology. The intake of minerals and chemical elements for food, water, soil (through geophagy) or dust can be accomplished by ingestion, inhalation or dermal absorption. Pelotherapy or ‘‘Mudtherapy’’ is the use of mud/clay for therapeutic applications, internal or external. Cape Verde archipelago is located in Atlantic ocean, 400 km westwards of Senegal coast. Geotourism is being developed, mainly focused on the development of a geopark in Fogo island huge caldera, but also trying to take advantage of their potentialities for Geomedecine. A cooperative program established between Cape Verde University (UCV) and Aveiro University (UA, Portugal) is under way, aiming, on a first stage, to identify Geotouristic potentialities and, on a second stage, to develop products. Geotourism is being developed, mainly focused on the development of a geopark in Fogo isl. huge caldera, but also trying to take advantage of their potentialities for Geomedecine. Ó 2014 Elsevier Ltd. All rights reserved.
1. Introduction and aims The concepts of geotourism and geoheritage have evolved significantly the last decade. Traditionally, the valuing and use of geological valuable areas as touristic resources has been linked to areas characterized by the beauty of the landscape, the spectacular rock formations or relevant/impressive features (mountains, glacier formations, rivers, canyons, caves, etc.) interesting for people loving geology or at least nature. However, both geologists and the Administration should design products and facilities making geology an attractive issue for any kind of tourists. In strict sense, geotourism is a tourism segment focused on the sustainable usufruct (by geotourists and local communities) of the geoheritage fruition. Geoheritage must be considered as all the natural abiotic elements present in the Earth surface, emerged or submerged (representing the geodiversity of the Earth), that should be preserved due to its heritage value. In broad sense, geotourism can be considered as a tourism segment mainly focused on the sustainable usufruct (by geotourists and local communities) of the geoheritage fruition, which can be added the cultural heritage (material and immaterial) of the areas. ⇑ Corresponding author. Tel.: +351 917696175. E-mail addresses:
[email protected] (F. Rocha),
[email protected] (E. Ferreira da Silva). http://dx.doi.org/10.1016/j.jafrearsci.2014.04.015 1464-343X/Ó 2014 Elsevier Ltd. All rights reserved.
In this sense geoheritage is the driving force of the geotourism itineraries, but the cultural heritage it is also added to increase the value of the visited regions. This broad concept of geotourism strengthens its ability as an additional resource to be included in a sustainable model of promotion and development of areas that preserve a rich and diversified heritage. Thus, Geotourism represents a fundamental tool to promote local economic development and cultural and social support to/from the community. When we speak about Geotourism the attention is usually preferentially paid to two main aspects involved in this concept: (1) the geology itself, and the geological values of the area, i.e. the scientific interest of the site, as the main subject of attraction for both geologists, students, visitors and tourists; (2) the administrations, at local or national level, which should set an adequate legal framework, in close agreement with geologists, to define, promote, arrange, restore and support the maintenance costs of the protected sites. Unlike the traditionally assumed view of Geotourism as an activity mainly depending on scientific and administrative factors, the potentiality and development of Geotourism depends (Fig. 1) largely on purely touristic constraints such as (Meléndez et al., 2011):
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Fig. 1. Main factors controlling the Geotourism development (from Moreira et al., 2008).
financial sources, touristic merchandising and facilities, easy connections with other touristic products, financial agreements and ‘‘bridges’’ with local administrations.
All these factors lie far behind the purely scientific interest of the site. The definition of protected areas and the quick growth of the number of geoparks and proposals for new candidates have meant a significant step forward in the process of: protect the Geological Heritage; create social concern and making geology a valuable instrument to foster local development and tourism. However, in the process of making Geology and Geodiversity a touristic attraction, both Geologists and the Administration often (Moreira et al., 2008) design products and facilities that are more related with research and with geodidactics or with explaining geology to school teachers, students, organized groups and occasionally for tourists than with making geology an attractive issue for tourists (see Fig. 2). Scientific research, teaching of Geology, social valuation and use of Geology and Geological Heritage and Geotourism are activities that require a decreasing amount of scientific transfer but, conversely, an increasing share of touristic (economic) benefit and possibilities for development and wealth for the area or the communities (Meléndez et al., 2011).
‘‘Real’’ Geotourism protagonists are groups of tourists with minimum, or none, knowledge of Geology, which come to visit the area (geopark or other) attracted simply by the beauty of the landscape or by having been told or seen it in a Nature or touristic guide. They may probably consider geological concepts and processes difficult but they will find it an exciting visit and will enjoy seeing beautiful and interesting things guided by good posters giving clear and simple explanations (Moreira et al., 2008). For socio-cultural sustainable development, Geoparks hold local workshops, festivals, fairs, and educational programs. Geoproducts which are made base on geological elements of Geoparks not only introduce the local products and the local handicrafts to visitors, but increase the public knowledge of visitors about geology and geomorphology. Nowadays the majority of geoparks are located in rural areas. Geoparks and geotourism are opportunities to rural developments and also promote the rate decline of unemployment and emigration through engaging the local communities in geopark activities and tourism marketing in the form of ecotourism, rural tourism and health geotourism. The establishment of a Geopark can be a way to promote regional food and crafts businesses as cultural components in rural areas. Creation of Geoparks can play a role in promoting local cuisine, products, and handicrafts as cultural components. It may be said that geotourism encompasses rural tourism and sustains or even enhances the geographical characteristics of a place. Tourism plays in Cape Verde a paramount role with huge socialeconomic impact. Till now, Cape Verde is seen mainly (almost exclusively) as a sea beach destination (bathing, fishing, diving). Public policies are being implemented in order to offer other touristic products, in particular those not affected by seasonality. Geotourism is being developed, mainly focused on the development of a geopark in Fogo isl. huge caldera, but also trying to take advantage of their potentialities for Geomedecine, such as: Boavista isl. and Maio isl. carbonated sands, Boavista isl. geophagic clays, Sal isl. clayey salt marshes and St. Antão isl. volcanic muds. A cooperative program established between Cape Verde University (UCV) and Aveiro University (UA, Portugal) is under way, aiming, on a first stage, to identify potentialities and, on a second stage, to develop products. Concerning geotourism survey, the program comprises bibliographic information and in situ observations in order to select sites and their relevant information (1st stage) as well as to define tracks for pedestrian and/or bike tourist itineraries (2nd stage). For each studied island, present situation must be stated as well as potentialities and needs must be putted forward. Concerning Medical Geology, the program comprises sampling performed on selected clay, carbonated sand and salt deposits on Boavista, Maio, Sal and St. Antão islands, followed by chemical and mineralogical characterization as well as assessment of other phys-
Fig. 2. Different activities generally performed by geologists in areas holding both scientific and heritage value and touristic potential, ordered according to the required scientific transfer of the activity (scientific content) and their touristic supply to the surrounding area (touristic content) (from Meléndez et al., 2011).
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Fig. 3. Mud/clay cookies (‘‘bon bon de terre’’).
ical and chemical properties considered relevant for these applications (1st stage), followed by beneficiation studies and tests for products development (2nd stage). In this paper, results of the first stages are presented.
2. Geotourism and Medical Geology Geotourism is closely linked with Medical Geology. The ubiquitous presence of minerals in the environment exposes humans to its effects, both positive and negative (Carretero, 2002; Gomes and Silva, 2007).
In what concerns the late ones, Environmental Geochemistry must assess the quality control of the touristic areas (in particular Potential Harmful Elements PHEs), in order to scientifically support the free and safe fruition of geological landscapes. Concerning the positive aspects, it is already a common concept that the human body requires chemical elements which can be obtained/produced by minerals such as Ca, Mg, K and Na, which we need in levels which may be considered high. However warn that they can also represent a risk of toxicity, depending on the dose and may even be lethal. Geophagy is the practice of eating terrestrial substances (such as clay), often to improve a poor mineral nutrition. The intake of
Fig. 4. Samples location (dots – sands; squares – clays).
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Fig. 5. Fogo huge caldera National Park.
minerals and chemical elements for food, water, soil (through geophagy) or dust can be accomplished by ingestion, inhalation or dermal absorption (Wilson, 2003). Mud/clay can be worked like cookies, sometimes called ‘‘bon bon de terre’’, which are sun-dried and sold throughout the poorer areas (Fig. 3). Small quantities of other ingredients such as salt and vegetables, sometimes sugar, are added. A recent trend developed in scientific research to study geophagy not as pathology, but rather as an ‘‘adaptive behavior’’, supplementing the diet with essential nutrients or treats a disorder (e.g. diarrhoea). On the other hand, topical employment of clayed materials for healing purposes has been documented since long time ago. Despite the lack of scientific support, their beneficial effects are unquestionable. Recent studies give scientific ground to the therapeutic action of muds (Carretero, 2002; Gomes and Silva, 2007; Veniale et al., 2004, 2007; Viseras et al., 2007). Pelotherapy or ‘‘Mudtherapy’’ is the use of mud/clay for therapeutic applications, internal or external. Pelotherapy can be defined as the ‘‘treatment through the application of a blend of clay minerals and mineral water’’. Therapeutic action of mud is not only due to heat sensation that leads to multiple reactions (vasodilatation, perspiration, stimulation of cardiac and respiratory frequency) but also due to antiinflammatory action and cation exchange between mud and skin. Due to the anti-inflammatory action, thermal muds have been indicated for recovering muscle-bone-skin pathologies: chronic rheumatic diseases, osteoarthritis, spondilo-arthritis ankylopoietic, spondylitis, myalgias and skin diseases. Sulfur can be absorbed through skin and may have an analgesic effect. The main advantages of Pelotherapy are (Carretero, 2002; Gomes and Silva, 2007):
application of a natural product on the skin; less aggressive for the patient than other methods; generally well tolerated; possibility of treatment of various pathologies with scarce resources
and St. Antão islands. A total of 16 samples were collected, 8 beach carbonated sands (SS1 and 2 from Sal; SB1 to 4 from Boavista; SM1 and 2 from Maio) and 8 clayey sediments/soils (CF1 and 2 from Fogo; CB1 to 4 from Boavista; CSA1 and 2 from St. Antão). Chemical composition was analyzed by X-ray Fluorescence and mineralogical composition was assessed by X-ray Diffraction (Galhano et al., 1999; Oliveira et al., 2002; Martins et al., 2007). To assess the potencialites of these geomaterials, samples (namely the finer ones: clays, clayey soils and volcanic silty muds) were also submitted to several technological tests, such as: cation exchange capacity to define the quantity of ions switched by the geomaterial; swelling power in order to evaluate the volume variation in conditions of compression, humidity and containment; consistency limits for the determination of the liquid limity, plasticity limity and index of plasticity; abrasivity for the determination of abrasion and index of abrasivity; cooling kinetics. All these tests were performed according to methodologies described by Quintela et al. (2010, 2012, 2014) and Rebelo et al. (2010, 2011).
4. Results and discussion 4.1. Cape Verde geotouristic survey – present situation, needs and potentialities Geotourism is already a reality on Fogo island although on a small scale and too much dependent on a single site (Fogo huge caldera; see Fig. 5) and still without adequate professional support. Accommodation, food/beverage and excursions economic activities are taking advantages of this ‘‘new’’ tourism.
3. Study area and methods Cape Verde archipelago is composed by 10 islands and 8 islets, located in Atlantic ocean, 400 km westwards of Senegal coast (Fig. 4). Cape Verde belongs to the Macaronesia region along with Madeira, Azores, Canarias and Savage islands. The islands (isl.) are from volcanic origin but their geology shows also sedimentary rocks, including clayey materials and carbonated sands. For the first stage of the program, and concerning geotourism survey, the approach was focused on bibliographic information and in situ observations in order to select sites and their relevant information as well as to allow the definition, on the second stage, of tracks for pedestrian and/or bike tourist itineraries. For each studied island, present situation is stated and detected potentialities as well as detected needs are putted forward. Concerning Medical Geology, sampling was performed on selected clay and carbonated sand deposits on Boavista, Maio, Sal
Fig. 6. Pedra Lume (Sal) salt marshes.
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Concerning Sal island, geotourism is very incipient and on residual scale, integrated on ‘‘safari’’ activities of sun and beach tourist products, with a singular attraction, the Pedra Lume salt marshes (Fig. 6). Geotourism is almost absent on Boavista island. Sand dunes are integrated on ‘‘safari’’ activities of sun and beach tourist products. Beach sands (Fig. 7) are calcitic and some clays are being sold as ‘‘healing clays’’. On Maio island, geotourism is also totally absent, evolving on a way similar to Boavista. The beach sands appears to be as richer in carbonated grains as those from Boavista island. The salt marshes are considered rich in Iodine (Fig. 8). Incipient Geotourism can be found in St. Antão island, focused only on pedestrian routes; first track maps and guides on English already available. Accommodation, food/beverage and excursions economic activities are beginning to take advantages of this ‘‘new’’ tourism. Volcanic silty muds (Fig. 9) are used as traditional ‘‘healing’’ materials.
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Some detected needs and potentialities are observed: upgrade of the smaller National Park team, in order to prepare the future Fogo Geopark; production of adequate multilingual information on geotouristic sites and routes, on all cases. quality assessment of geomaterials (carbonated sands; clays; clayey soils) with potential applications on Geomedecine (Fogo, Sal, Boavista). quality assessment of clayey salt marshes for thermal mineral– waters baths (Sal island). development and diversification of products. 4.2. Cape Verde Medical Geology survey – properties assessment Clay rich soil levels from Fogo, Boavista clays and sands, Sal sands and St. Antão volcanic silty muds were submitted to mineralogical (Table 1) and chemical (Table 2) analysis, and some other
Fig. 7. Boavista carbonated sands (left) and smectitic geophagic clays (centre and right).
Fig. 8. Maio ‘‘golden’’ carbonated sands.
Fig. 9. St. Antão volcanic silty muds.
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Table 1 Mineralogical composition (XRD). Sample
Qz
Opal
Felds
Fe-ox
Al-ox
Calc
Arag
Mg-calc
Phyll
Sm
Ill-Sm
Ill
Kt
CF1 CF2 CB1 CB2 CB3 CB4 CSA1 CSA2 SS1 SS2 SB1 SB2 SB3 SB4 SM1 SM2
41 40 50 52 tr tr 35 38 3 4 tr tr tr tr 2 2
0 0 0 0 0 0 15 17
17 20 10 9 42 37 18 17 tr tr 0 0 0 0 0 0
7 8 4 3 6 5 3 3 0 0 0 0 0 0 0 0
6 6 3 3 3 3 4 5 0 0 0 0 0 0 0 0
4 3 5 3 4 5 0 0 82 81 65 65 65 65 75 77
0 0 0 0 0 0 0 0 10 10 20 25 25 20 15 15
0 0 0 0 0 0 0 0 5 5 15 10 10 15 8 6
25 23 28 30 45 50 25 20 tr tr 0 0 0 0 tr tr
15 5 5 10 50 60 0 0 nd nd nd nd nd nd nd nd
35 35 10 15 15 25 25 20 nd nd nd nd nd nd nd nd
25 30 55 50 20 5 40 45 nd nd nd nd nd nd nd nd
25 30 30 25 15 10 35 35 nd nd nd nd nd nd nd nd
Qz – quartz; Felds – feldspars; Fe ox – iron oxides; Al ox – aluminum oxides; Calc – calcite; Arag – aragonite; Mg calc – magnesium calcite; Phyll – phyllosilicates; Sm – smectite; Ill-Sm – illite-smectite mixed-layers; Ill – illite; Kt – kaolinite.
Table 2 Chemical composition (XRF). Sample
SiO2
Al2O3
CaO
MgO
Fe2O3
K2O
Na2O
TiO2
MnO
LOI
CF1 CF2 CB1 CB2 CB3 CB4 CSA1 CSA2 SS1 SS2 SB1 SB2 SB3 SB4 SM1 SM2
57.13 56.82 57.87 58.12 50.28 50.01 65.93 66.04 2.91 3.47 1.51 1.74 1.59 1.61 2.43 2.71
14.59 14.24 15.55 16.10 18.14 18.52 12.11 12.08 2.11 1.95 1.12 1.32 1.14 1.17 1.43 1.62
3.76 2.82 3.51 2.75 6.06 6.08 2.79 2.51 49.02 48.71 51.05 50.97 50.94 51.02 50.39 50.03
3.34 3.86 1.77 1.92 3.21 3.43 2.25 2.17 1.71 2.02 3.21 3.11 3.13 3.16 3.03 2.69
5.68 5.76 4.10 4.37 4.65 4.68 2.44 2.51 1.26 1.01 0.93 0.96 0.94 0.96 0.91 0.99
3.81 3.84 3.91 3.76 2.21 1.59 3.83 3.88 0.91 1.05 0.35 0.36 0.38 0.37 0.39 0.45
1.83 1.85 1.29 1.37 3.02 3.04 1.88 1.91 1.65 1.93 0.65 0.68 0.72 0.68 0.71 0.85
0.81 0.83 0.65 0.61 0.79 0.76 0.65 0.53 0.17 0.21 0.19 0.17 0.18 0.19 0.14 0.19
0.03 0.03 0.04 0.03 0.02 0.02 0.03 0.03 0.13 0.14 0.12 0.11 0.13 0.12 0.10 0.12
10.02 9.95 11.31 11.87 12.82 13.07 8.09 8.34 40.13 40.01 40.87 40.57 40.65 40.72 40.47 40.35
LOI – lost on ignition. Table 3 Technological properties. Sample
Plasticity index (%)
Swelling (%)
Abrasiveness (g/m2)
CTC (meq/100 g)
SSA (m2/g)
Cooling rate (min)
CF1 CF2 CB1 CB2 CB3 CB4 CSA1 CSA2
25 22 17 21 31 37 5 4
17 15 12 13 21 23 3 2
0.18 0.17 0.21 0.19 0.14 0.13 0.25 0.27
35 33 21 24 50 52 12 10
24 22 18 16 27 29 13 12
21 23 18 19 25 27 15 16
CTC – cation exchange capacity; SSA – specific surface area.
properties (Table 3) such as cation exchange capacity (CEC), swelling (expandability), plasticity index, abrasivity and cooling kinetics (cooling rate). Some clay-rich soil levels were found on Fogo island (north of capital town, S. Filipe) presenting higher proportions of phyllosilicates (mainly illite–smectite with some kaolinite) and iron oxides and showing medium CEC, swelling and cooling kinetics values, good plasticity and relatively high abrasivity. Chemical analysis are in accordance with this composition, showing higher contents on silica, aluminum, iron, magnesium, potassium and calcium (Table 2). Boavista sampled clays (on the coast west of Rabil airport and on middle east of the island, between Rabil and Fundo das Figueiras) are composed by illite, smectite and kaolinite, the western
deposit (Rabil) being more illitic and the eastern much more smectitic (Fig. 10 shows representative DRX curves); both show good values for the assessed technological parameters, but the eastern showed higher values for CEC, specific surface area and plasticity as well as finer mean grain size and low cooling rate. Boavista clays are richer in aluminum (all), potassium (western ones) and magnesium and calcium (eastern ones) than those from Fogo. First mineralogical analysis of the volcanic silty muds from St. Antão point to a composition of quartz, opal, K-feldspars, alumina and iron oxides, and phyllosilicates (mainly kaolinite and illite– smectite). Samples are richer in silica and iron than those from Boavista and Fogo and showing lower values for CEC, specific surface area and plasticity as well as coarser mean grain size and higher cooling rate.
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Fig. 10. XRD of CB1 (sample 1) and CB4 (sample 2).
Santa Maria (Sal island) beach and all Boavista beaches sands are composed by calcite, magnesium calcite and aragonite, silicates (quartz and feldspars being scarce) but Boavista ones are richer in all carbonates (silicates almost totally absent).
Geoparks must contribute to development of local economy via involvement of local communities in geotourism marketing and geoparks activities such as organizing conservation projects, workshops and educational programs. Cape Verde Geotourism and Geomedecine Project (UCV/UA) represent a very promising tool to booster Geotourism in Cape Verde. On-going research of the second stage will be focused on:
5. Conclusions We need to understand Geotourism as a touristic, not academic, activity. Geotourism means, besides Geology, accommodation and eating facilities, the quality of accesses and services, and the excellence and attraction of merchandising products.
definition of tracks for pedestrian and/or bike tourist itineraries; more detailed assessment of mineralogical, geochemical and technological properties of the geomaterials, considered as having potential interest to Geomedicine applications with geotouristic impact;
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geological survey to estimate actual reserves and internal variability of the detected deposits; development of geoproducts (pelloid muds; exfoliants and other dermocosmectics).
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