Inter. J. Environ. Studies, 1999, Vol. 56, pp. 833 847
(c) 1999 OPA (Overseas Publishers Association) N.V.

(Received in final form 2 November 1998)

The Aeolian archipelago is undergoing social and economical changes that threaten its natural and cultural patrimony, which is also the essence of a tourist appeal, as an image of uncontaminated sites, where nature's ancestral phenomena and seasonal rhythms are experienced. Salina island may serve as a prototype for exploring the possibility of implementing conservation strategies compatible with human needs, landscape preservation and sustainable economic development. By means of the CORINE methodology, "ecological sensitivity" (from a functional viewpoint) and "ecological vulnerability" (either physical or ecological) maps have been drawn to objectively quantify the environmental risk. Some final remarks are devoted to clarify the concepts of "environmental perception" and "citizens' consent".

Keywords. Aeolian archipelago; ecotourism; human carrying capacity; GIS; CORINE biotopes; ecological sustainability and vulnerability

1. INTRODUCTION

When UNESCO promoted the program "Man and Biosphere" (MAB), aimed at favoring the active experimentation of development policies compatible with natural heritage protection, a brand new prospective emerged for approaching environmental aspects of human concern. MAB's Project 7 focused on small island ecosystems that included the Aeolians Project. In this Project the involvement of researchers from different scientific disciplines actually eliminated the narrow focus usually involved with any specialized sector, in the attempt to produce new results through the "breeding" of knowledge from fields traditionally far apart.

The Aeolian archipelago (Northern Sicily, Italy) is particularly suitable for this purpose, the seven inhabited islands, whose surface areas range from 3 to 37 square kin, are rich in interesting natural and human characteristics. Geographically close, but nonetheless diversified in many aspects (geological origin and morphology, flora and fauna, historical events, landscape characteristics, agriculture and fishing activities, trading, and so on), for decades the islands have been under scientific investigation as a natural laboratory and an almost unique observatory for studies on carrying capacity in a highly fragile environment.

The Aeolians' natural heritage and landscape resources are still poorly understood, but there is no doubt that any social and economical development policy will have to jealously conserve such a patrimony, which is also quite appealing to tourists. Sampling investigations [1, 2] focusing on this very aspect, demonstrate that most of the tourist flow on a small island is based on the image of an uncontaminated site, where nature's ancestral phenomena and seasonal rhythms can still be directly experienced.

What follows is an overview of interdisciplinary research that focuses on the island of Salina (25 square km, about 2,200 inhabitants); nevertheless most of the statements can be extended to the entire archipelago.

2. A MATTER OF FRAGILITY

The dynamics of the Aeolian archipelago have always been extremely fragile, resulting in strong fluctuations in the islands' carrying capacity [3]. The various components are balanced somehow in a highly unstable equilibrium with a reduced capacity to buffer the effects of relevant disturbing agents.

The problem of the archipelago's stability is directly linked to its economic development: conflicting processes often originate from the need to support the local populations and to ensure compatibility with the islands' stability. Furthermore, the managerial aspects to be considered are heterogeneous in terms of both reference scale and type of measurement, and are thus difficult to define.

Technological innovations play a strategic role in these small environments [4], but they must be promoted and managed cautiously. Over the past years [5] failures due to unforeseen destabilizing effects were often caused by (i) technological impacts on the natural and human equilibria, (ii) insufficient insitu human resources (not even one island has 5,000 inhabitants), (iii) lack of financial resources to ensure continuity for the initial effort.

Beyond any other considerations, the Aeolian citizens are not yet prepared to sustain the sudden impact with the "external world" as this kind of development requires. It is also necessary to understand how much the policies aimed at favoring such growth would be desirable, and whether this peculiar development would effect the island's attractiveness. If this were the case, other key issues would fail to consolidate and, as a consequence, disapproval for activities related to them could spread, generating prejudice against any durable sustainable planning.

The quality of life on the archipelago is becoming such an important issue, that administrators and policy planners will have to deal with it [6]. If, during the economic boom of the 1960s, the concept of quality of life was based exclusively on monetary parameters (per capita income, exclusive use of structures, etc.), nowadays it has become more allembracing, due to the impact the development has had on the whole sociocultural and environmental reality.

As a matter of fact, the Aeolian socioeconomic system, like that of many small islands in the world [7], is undergoing a very delicate transition period, that is also reinforced by the spontaneous reactions of the local people to geographical insulation, socioeconomic marginality and land abandonment. The widening gap between human productive activities and the quality of the environment has caused massive emigration and, consequently, the development of opportunistic tertiary activities that are often uncontrolled and badly planned.

Today, the promotion of better human living conditions involves environmental protection, wellbeing of the population, recreational spaces and cultural activities, so that economic growth must be integrated within a perspective of balanced global development.

3. CHALLENGES TO FACE

3.1. Demography

Population forecasting has become an indispensable scientific tool for environmental planning. In fact, man's presence is fundamental to the management of natural resources which is, more than anything else, the management of limits [8]. While the economic system has mastered the instruments and reasoning of a future oriented culture, the political administrative structure still seems to be making choices, even the strategic ones, on a handtomouth basis. These choices are dictated by the "logic of emergency", according to which problems are dealt with only when they can no longer be put off. These methods of political management of populations and land use have high social, economic, environmental and human costs, that could, at least partially, be prevented if their consequences on the population were foreseen.

It has been the constant concern of the Council of Europe [9, 10] to convince public and private administrators that political and entrepreneurial planning become effective and useful for the entire community only when the choices regarding the economic and social development of a population are consonant with its demographic transformations. Although education, public welfare, health and social assistance are extremely important, the factors fundamental to the productive system and economic survival of small islands are the dearth of young workers, the transformation of the active population [11], and the nature of the job market.

To illustrate the possible consequences of current smallisland demographic trends, the national forecasts have been utilized in accordance with method hypotheses formulated by the United Nations [12]; these estimates follow a classic pattern, with upper, middle and lower variant estimations. The discriminating criterion is the average number of children per woman, computed for people of the same age [13]; the most probable current or estimated value determines the middle variant, while the other two variants are linked to reasonable hypotheses of change in terms of increase or decrease.

3.2. Economics

The recent economic history of the Aeolians, compared to all the small islands in Southern Europe, has been linked to four basic "survival factors": emigration, remittance, economic aid, government concessions. Long term excess population and little opportunity for work at home led to emigration, particularly by the young people of the islands. This, in turn, resulted in the sending back of funds to family members who remained. The government concessions to island inhabitants are motivated by the severe economic vulnerability of these areas which, because of their particular geographical position and small size, sustain higher transport costs for both products and persons.

In the past, although population density was contained, and pressure on land was modest, these isles were rarely able to increase the number of jobs at the rate at which the young part of the population expanded. Aside from the scarcity of capital for investments and higher educational costs, the difficulty of creating local technical competencies required by more intense development, has been the limiting factor. In fact, unless they emigrate, the better prepared young people only rarely find satisfactory conditions for their legitimate aspirations and personal gratification, in both economic and cultural terms. Because of the lack of technical personnel and the emigration, the Aeolians have always been characterized by lower economic development, reduced efficiency and specialization of services, and more widely diffused poverty, unless one considers the strong influx of external capital.

Nowadays, for instance, the primary sector in Salina is still going through a crisis caused by inadequate environmental conditions (geographic marginality, irregular morphology, very steep slopes, semiarid windy climate with a long dry season) and the insufficiency of productive resources (shallow soils with rock outcrops, scarcity of irrigation, small sized farms). Moreover, agricultural difficulties have been enhanced by specialized cropping, such as capers and grapevines [14]. The development of seaside tourism has partly masked the consequences of such a crisis, but this renders the phenomenon even more dangerous.

Within this context, environmental managers and land use planners are naturally tempted to provide unskilled, lowpaying jobs, and to avoid challenges to modernization [15]. This is the case with the primary sector, where it seems urgent to promote a program of modernized sustainable development, through technologies that enhance the competitiveness of the productive processes and foster high quality products while respecting environmental resources.

3.3. Tourism

The most important phenomenon in the last three decades has been the intense growth of tourism, which has created new prospects for the weak economy of the islands. Lipari, Vulcano and Stromboli have undergone a remarkable transformation: both the economy (commerce, new jobs) and the infrastructure (electricity, communications, transport) have grown considerably. Yet, in just a few years, these benefits could be neutralized by the impact that the phenomenon, in rapid and haphazard expansion, might have on a landscape characterized by high seismic and volcanic risk, fragile biological communities, excessive dependence on the external market, and a chronic scarcity of vital resources, such as water and energy. The uncertain longterm prospects, together with the destruction of the environment and natural beauty caused by mass tourism, require rapid coordinated intervention that combines the capacity to enhance the quality of the environment with the economic advantages made possible by new activities.

The development of the tourism industry ("the largest business on earth" [16]) is producing growth not known in other economical sectors: it strengthens the archipelago economy, trading, the real estate market and the entire building industry, offers opportunities for appealing jobs, and so on. Undoubtedly tourism has meant better economic conditions (reliable indicators of per person income classify the Aeolian communities as some of the "richest" in Sicily); but, at the same time, environmental degradation has occurred, and the lack of key resources (energy, water, beaches, etc.) is leading to major unbalances. Dire consequences will eventually occur, unless the expansion of such environmentconsuming activities is supported by shrewd planning instruments.

These general difficulties often occur in isolated areas. Yet small islands are systems which are also more fragile and sensitive to any type of variations: (i) reductions in population bring about wider oscillations in its structure, with major alterations of productive organizations and social networks, (ii) the limited geographic size imposes specialization that lowers to a minimum the possibility of varying land use planning and the type of development forced by the changing needs of the community.

Unfortunately, the tourism demand in all Mediterranean isles is seasonal by nature, and this overloads the use of natural and human resources as well as island infrastructures in a very short period of time [17]. Instead, in the remaining months lodging facilities and other public services remain almost abandoned: it goes without saying that any planning process is hindered by serious economic problems that turn out to be much more acute than elsewhere.

The suggested solution to many of the damaging effects of tourism on environmental and socioeconomic conditions, that was spread rapidly over these last few years, is ecotourism [1820]. There is still no agreement as to what "ecotourism" means when put into actual practice. It is unclear, therefore, whether the idea of ecotourism will make a difference to public administrators, businessmen, and individuals involved in the development of tourism. Indeed, it is reasonable to believe that ecotourism won't avoid the many undesirable impacts on environment and society [21].

Ecotourism and sustainable tourism development are valuable in that they indicate desirable directions for the tourist industry. Their stress on lowintensity activities, on limiting social and environmental effects, and on equity with regard to the benefits and costs of tourism, are likely to lead to more acceptable types of tourism development [22]. However, these concepts are general and their actual meaning has to be elaborated in relation to local economic, social, cultural, and environmental conditions.

In this respect, planning and management procedures should address the following: setting of goals and objectives [231; research to provide a good understanding of relevant ecological and socioeconomic systems [24]; environmental education [25]; ethical issues [26]; assessing procedures [27]. A basic principle for the above is the involvement of all affected parties, which can be aided by focusing on decisionmaking processes [28] and especially on key processes such as understanding, communicating planning monitoring, and adapting to changes.

4. RESEARCH AGENDA

Presently, new ideas and hypotheses concerning further development of small islands are often presented. However, based on negative and contradictory environmental consequences experienced by others, new operating methodologies must be proposed that, through the integration of all available information, can avoid past mistakes.

4.1. The CORINE Biotopes Method

In 1991 the European Community Council proposed to all Member States a new methodology for identifying and recording sites of Community importance for nature conservation. This methodology, established within the framework of the CORINE (COordination of INformation on the Environment) biotopes program, is fully described in an official manual where a hierarchical list of identifiable sites (also called habitats or environmental units, EnUns) at the Community level is given [29].

Basic theoretical criteria for identifying an EnUn are: (i) units whose surface is large enough to constitute important habitats for animal species with extensive space requirements; (ii) physiogonomically significant units in the landscape; (iii) units essential to the survival of distinctive populations of rare or sensitive plants/animals; (iv) units which are peculiar elements of larger ecosystems; (v) units remarkable for the ecological processes they host or for their aesthetic value.

Pilot research based on this methodology has been performed on the island of Salina. The procedure adopted to identify EnUns essential for nature conservation are broken down into four steps:
- collection of basic data and information to gather preliminary qualitative knowledge of abiotic and biotic profiles of the island (geomorphological traits, categories of soil usage, vegetational types and cover, faunal lists, etc.);
- identification of EnUns included in the official European CORINE biotopes list with best fit with the territorial profiles;
- outline of EnUns borders as they occur from soil usage evaluation and other relevant environmental information;
- final EnUn assessment in structural terms, by stereoscopic examination of aerial pictures and by brief field surveys. As a result, 120 Salina EnUns that fully correspond to typologies on the CORINE biotopes list were identified: the resulting complex mosaic makes the resolving power of this approach quite apparent.

Such identification is the necessary starting point to evaluate, initially, ecological sensitivity and vulnerability with regard to new development hypotheses for Salina.

4.2. Ecological Sensitivity and Vulnerability Maps

The Salina EnUns have been evaluated essentially according to an appropriate set of environmental indicators. Ecological sensitivity refers to those plant/animal populations which characterize a given EnUn under a precise ecological functional viewpoint.

The set of plant/animal population traits for rarity, sensitivity to man's presence, and recovery time after perturbation, was tested for independence and provided a score for each EnUn within a bounded range covering all possible outcomes. When the score is low, such populations (i) are present at different spatial /temporal scales, (ii) are not very sensitive to man's presence, and (iii) recover relatively quickly after interference. On the contrary, high scores reflect situations where populations (i) are rare, (ii) are very sensitive to man's presence, and (iii) have poor recovery capacity. Final scores thus tend to provide an overall evaluation at the population community ecological level.

The map of ecological sensitivity shows that large parts of the most sensitive EnUns are within the border of the natural reserve of Salina, with some exceptions such as phanerogam meadows, where Posidonia oceanica Delile beds were the most sensitive biological component. Moreover, almost the entire insular area is characterized by environmental units with a midhigh degree of ecological sensitivity, obviously excluding the villages of Santa Marina, Malfa, Leni and Rinella. This uniform but relevant ecological sensitivity trait largely exceeds the reserve border and also includes cultivated soils. In other words, both aspects of nature, either in its concentrated form (natural reserve) or in a more widespread presence (cultivated soils), are not so different in terms of ecological sensitivity, but, on the contrary, they are strictly linked to yield a unique environmental system. This functional interdependence is the very basis of the island's beautiful environmental features and what makes it a great tourist attraction.

Salina's ecological vulnerability map has also been drawn. The term "vulnerability" (it comes from the Latin vulnus, wound) refers to the environment's risk of being damaged. Such a risk depends on both intrinsic environmental sensitivity and man's pressure. Vulnerability can be classified as physical or ecological: the first depends on physicalgeomorphological degradation, the second on ecological sensitivity, whereas both depend on the intensity of man's pressure. The ecological vulnerability of a given EnUn is related to the intensity of man's pressure on the unit, with its coefficient of ecological sensitivity. Ecological vulnerability is particularly high for phanerogam meadows, because of their intrinsic fragility and role as a "nursery" and "shelter", essential for the reproductive processes and the life cycle of almost all marine littoral plant/animal populations, as well as coastal bird species.

Now looking at the entire island, it turns out that available spaces suitable for new tourist structures and infrastructures are quite limited. They can be represented by narrow corridors that are very close either to the natural reserve or to the coast. The adequacy of these areas to new tourist settlements must be evaluated very carefully, since it is essential to choose areas with low ecological sensitivity and vulnerability. For an EnUn with low ecological sensitivity, a small increase in tourism produces a corresponding small increase in vulnerability, whereas, for an EnUn with high ecological sensitivity, a small increase in tourism gives rise to a remarkable increase in vulnerability.

Considering these essential environmental constraints, some proposed infrastructures for Salina and other islands, like a heliport, incinerator, and so on, turn out to be critical because the areas involved have low vulnerability but also relevant ecological sensitivity.

5. CONCLUDING REMARKS

5.1. Public Consent

To ensure that the development processes will respect the local people and their own expectations, choices and decisions must be made together with the inhabitants. This level of understanding needs to be investigated [30], because researchers and political administrators agree that it is an essential component to ensure that innovations and renovations will succeed.

But it is difficult to concretize the socalled "environmental perception" and to measure "citizens' consent". The interactions between natural environment and human reality are usually based on needs that lead to conflicts, generally satisfied by hasty territorial transformations as well as by compromises in current management.

Better understanding of anthropogenic components related to marginality is required and can be achieved through investigations about the inhabitants' everyday lifestyle [2]. Wellknown problems call for adequate solutions: drinking water is chronically insufficient, so huge quantities are imported from the continent at high cost; youth migration worsens agricultural abandonment; transports within and between islands and to/from the continent are inadequate and substantially unreliable; health care, the educational system, waste disposal, energy sources, and other community services are exacerbated by scale diseconomies.

During these years marked by an ever increasing "freetime market", there is an urgent need for balanced and accurate planning of the territory. The political strategies aimed at increasing or diminishing external pressures must take into account numerous requirements, often conflicting, of both the natural environment and the islanders. The guidelines, based on the results of scientific field surveys, and on natural and cultural heritage oriented sustainable tourism, will include recommendations for the effective protection of particularly vulnerable areas, landscapes and monuments, and will be addressed to national and local decisionmakers as well as entrepreneurship.

Field surveys can be carried out through a series of methods defined as multiple criteria analyses, that permit the comparison of alternative choices in relation to the consequences of various aspects of a given reality, without requiring any monetary evaluation of the effects. Multicriteria analyses eliminate the need for homogeneous dimensions during comparison, by using the principle of relative priority: according to this principle, one solution is preferable to another on the basis of given criteria which relate to the intensity of each quantitative variable, or else the evaluation is codified according to the rank of qualitative components when objective data are unreliable or unobtainable.

5.2. Mapping the Environment

To achieve the goal of sustainable development of small islands, there is urgent need for rational procedures that can integrate all the available information to create a decisionsupport system for choosing among different planning alternatives aimed at sustainability.

The creation of ecological sensitivity and vulnerability maps is specifically requested by Italian law to define fundamental lines for land use and management. When applied to the island of Salina, such a methodology has produced quite interesting results. From the mapping of environmental sensitivity and vulnerability for the island of Salina, the present boundaries of the Natural Reserve were found to be unable to cover all the most sensible and vulnerable areas.

Moreover, territorial plans foreseeing new tourist settlements and infrastructures must take into account ecological sensitivity values, that are quite relevant for almost the entire Salina territory. Criteria applied to identify environmental units stem from those agreed upon at the European Community level as a directive and adopted by each Member State.

These results are drawn up with environmental thematic maps using a geographical information system (GIS). The new methodology adopted may be of great importance not only to find solutions for sustainable tourist development on the island of Salina, but also for all the situations (small islands) where it is crucial to find a rational compromise between environmental conservation and socioeconomic development exigencies.

5.3. International Cooperation

The Mediterranean sea, with its many small islands, is a vast enclosure assaulted by human activity, and both the islands and the waters are in peril. Therefore it would be helpful to develop a prototype project for subsequent research in the Mediterranean basin a project to save the islands of the Mediterranean and the sea itself. The scope of this plan to save the Mediterranean is necessarily large, but also unwieldy: the main point is to create an authority for the Southern European sea that might be called the Authority of the Mediterranean sea [31].

The Authority would be a decisionmaking and scientific agency, taking action to bring all viewpoints into discussion and to create a consensus to resolve disputes. Where conflicting parties refuse to participate or they intentionally impede the procedures, then the Authority would have the power to either pressure the parties to submit to deliberation or make the final decision without any recourse for appeal by the parties.

Members of the Authority Board would include scientists and university professors, from all the natural, economic, and social sciences. The Board also includes the regional administrative agencies. Each island in the region would have a representative on the Board. Additional membership might be extended to (i) local nongovernmental organizations with scientific expertise related to environmental protection, (ii) representation by the Italian government through agencies related to environmental protection and economic development, plus (iii) a designated member from the European Union and (ii) international agencies such as UNESCO or UNEP.

Among other commitments, the Authority would be charged to oversee and fund research and scientific inquiry. The decisionmaking process would require the acquisition of scientific information. In addition, the authority would develop longterm monitoring programs, to inform the public, and act to protect the interests of both the general population and the Southern Mediterranean ecosystem. It would consider the human economic needs of the region bordering the Southern Mediterranean triangle and the islands, but also within the broader view of sustainability of natural resources as well as human health and safety.

Acknowledgements

UNESCO and INSULA Intl. offices help (headquarters in Paris, France) is kindly acknowledged for their continuing support and P.R. efforts. Prof. Lamberto Soliani's (Univ. Parma) works on islands' demographics has been considered all through the Paper. J. G. Nelson's (Univ. Waterloo, Canada) and M. L. Miller's (Univ. Washington, Seattle, WA) papers about ecotourism offered a valuable inspiration for our comments. Charles J. Puccia (formerly at Union of Concerned Scientists, Boston, MA) provided sound suggestions for the remark about the Authority. The authors wish to thank all of them.

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