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Indicators of tourism development of the Serbian Danube region

Protected natural area in the Danube region covers 107,200 hectares and includes two national parks, two nature parks, one place of outstanding natural beauty, five special natural reserves, twenty-five nature monuments, and two sites of international significance included in the Ramsar list. However, only 140 immovable and 374 movable cultural objects are officially registered. There are 31 cultural objects of exceptional importance and national significance and 89 objects of great importance and regional significance. The objects with this status are protected by the state. Two sites are on the preliminary UNESCO World Heritage list. This paper discusses the potential of tourism industry in the Serbian Danube Region and the prospects of its further development. We outline the current state of tourism industry and describe the geographical location of the region, its natural and anthropogenic resources, and accommodation capacities. We analyse such data as the number of tourists and the number of overnight stays by municipalities in 2016, and the average length of stay. The indicators used are the functionality coefficient, the capacity utilization and the intensity of functionality. The conclusion is drawn that the tourism potential of the Serbian Danube Region is not fully realized and that its development should be at a much higher level, given the increasingly important role of the region as a major tourist destination in Serbia.


Introduction
The Serbian Danube Region is a destination that is gaining more and more importance on the tourist market of Serbia. The region offers a variety of diverse tourist attractions ranging from natural parks and reserves to cultural heritage sites [1]. However, the abundance of resources does not always guarantee commercial success [2]. Therefore, it is important to define the direction for development of tourism in the region, to achieve the synergy of all the key factors, and to cooperate with other local partners to promote the Serbian Danube Region as a major tourist destination. The goal is to boost revenues of the tourism industry by increasing the number of tourists and the number of overnight stays. The growth in the tourism sector would create more jobs, reduce the outflow of the population to other regions and improve the living standards of the local community [3].

Theoretical framework
Until the second half of the twentieth century, the data on tourist arrivals, number of beds and the average length of stay as well as the number of people employed in tourism and hospitality industry had been the key indicators for assessment of tourism development in specific destinations [4]. Later, in order to determine the impact of tourism on local economies, the research started to focus on the ratio of accommodation capacities and the number of local population in specific destinations [5; 6]. The first to apply this type of methodology was French geographer Pierre Defert, who proposed the index of tourist function in 1967. French researcher Rene Baretje in 1978 improved Defert index and brought it in agreement with the spatial unit of destination. Numerous studies introduced other indicators, in addition to Defert-Baretje's index, for measuring the tourist intensity. For example, Polish researchers used Charvat's index to show the development of tourism as a result of urbanization. The intensity of tourism can also be determined with the help of Schneider's index, which is often referred to as the index of tourist traffic intensity [7].

Description of the region
The Serbian Danube Region extends between 45°48'39" and 44°12'48" north latitude and 18° 51'9"and 22°40'18" east longitude. This region is located in Central Europe in the southern part of the Pannonian Basin, in the north of the Republic of Serbia [8]. The Danube Region in Serbia covers 15,755 km 2 , which is about 17.8% of its total area. According to the last census, there are 2,957,577 people in 499 settlements, that is, about 40.7% of the total population of Serbia. The average population density is 125 inhabitants per km 2 . The region comprises 24 local self-government units that have a direct access to the Danube. The territory can be divided into the following parts: -the upper Danube Region, the area located along the border with Croatia from Batina (Bezdan) to Bačka Palanka. Recently, this region has significantly changed its spatial and functional characteristics; the central Danube Region, the area from Bačka Palanka to Ram, which includes the largest and most important centres in Serbia. This region has retained its previous characteristics and does not require any changes in the planning and arranging of its territory; the lower Danube Region, the area from Ram to Prahovo, located on the border with Romania. This region holds considerable potential in the sphere of trans-border cooperation [9].
Within the Serbian Danube Region, there are areas that enjoy the status of internationally protected areas and those with the candidate status: for example, Gornje Podunavlje and Labudovo okno are already included in the list of Ramsar sites, while Koviljsko-Petrovaradinski rit and Donje Podunavlje are awaiting to be approved. Such areas as Gornje Podunavlje, Deliblatska peščara and Djerdap have the status of recognized biosphere reserves within the UNESCO's Man and the Biosphere (MAB) Programme. Djerdap National Park is covered by the Framework Convention on the Protection and Sustainable Development of the Carpathians. Serbia has also submitted nomination proposals for Deliblatska peščara and Djerdap National Park to be included into the World Heritage List on the basis of the Convention on the Protection of the World Cultural and Heritage Site [10].
There are 1,186 objects of cultural significance in the Serbian Danube Region. However, only 140 immovable and 374 movable cultural objects are officially registered. There are 31 cultural objects of exceptional importance and national significance and 89 objects of great importance and regional significance. The objects with this status are protected by the state. The town of Bač and Smederevo fortress with its surroundings have been on the preliminary UNESCO World Heritage list since 2010. All these natural and anthropogenic resources of the Serbian Danube Region are a part of the European heritage, which can be used as the starting point for their promotion and marketing as tourist attractions [11].
The peculiar feature of tourism in the Serbian Danube Region is the number and diversity of the natural and anthropogenic landmarks concentrated in a relatively small territory. The problem that needs to be addressed is the low level of their attractiveness for tourists. Moreover, tourists' awareness about these spots is also low [12]. It is known that the Danube is one of the most popular river boat destinations: it ranks first in the world by the number of tourists that visit it on boat cruises. In 2008, out of 380,000 German and Austrian tourists that travelled on international tourist boats, only 51,000 stopped in Belgrade [13]. On the one hand, there are fortresses such as Kalemegdan and Petrovaradin, whose promotion is ineffective; on the other hand, there are also fortresses that remain largely unknown to tourists. The most attractive cultural landmark in the region is the archaeological park Viminacium. Another example of successful promotion is Lepenski Vir: since 2012, the efficient marketing campaign has made it much more interesting for tourists. There is currently no adequate record of accommodation in Serbia and it is not possible to give a complete overview of accommodation facilities and complementary accommodation facilities. Although many towns and municipalities on the Danube hold a great potential for the development of tourism, they have a poor tourist infrastructure [14]. In our analysis we are using the data provided by the Statistical Office of the Republic of Serbia.
As statistics show, in 2016, 1,250,308 tourists arrived in the Serbian Danube Region and spent 2,647,347 nights. The average length of stay of domestic tourists was 2.3 days, while foreign tourists stayed for 2 days. Interestingly enough, twice as many foreign tourists as domestic ones visited the region in the given period.
In 2016, 299 accommodation facilities were registered in the Serbian Danube Region. These facilities offer 15,688 rooms and 33,176 beds, with 31,827 permanent and 1,349 extra beds (Table 2). Accommodation services are predominantly provided by hotels.
There are 138 hotels in the Serbian Danube Region, all of them categorized. Hotels of a lower category have 8,868 rooms and 15,688 beds. In the region, there are 5 five-star hotels, 38 fourstar hotels, 26 three-star hotels, 14 two-star hotels and 4 one-star hotels. There are also two apartment hotels (a five-star and a four-star). As for garni hotels, there is one five-star, 18 four-star, 25 three-star, 4 two-star, and a one-star. In addition to the hotels, the Serbian Danube Region also has one boarding house, 3 motels, 61 overnight stays, 9 apartments, 17 inns with accommodation, 3 spa centres, 2 mountain huts, 3 children's and youth resorts, 57 hostels, 4 camps, and a car for sleeping. There are seven other accommodation facilities, including campsites, hunting lodges and huts, tourist resorts [15]. Hotels are well-equipped to accommodate large tourist groups as well as conference guests. However, the average occupancy rate in the Serbian Danube Region is low and, therefore, hotels' annual revenues are quite modest [14]. The largest number of tourists come to Belgrade and Novi Sad. Thus, it is the hotel industry in these areas that has the greatest impact on economy. For more balanced development of tourism industry in the Serbian Danube Region it is necessary to build many more facilities for accommodation of tourists in other parts of the region.
The number of foreign tourist arrivals in 2016 was 885,672 or 70.8% of the total number of arrivals. Foreign tourists made 1,808,924 overnight stays, which is 68.3% of the total number of overnight stays in the Danube Region ( Table 3). The large proportion of foreign tourists indicate the increasing importance of foreign tourism for the development of the region. The absolute values of the tourist traffic as well as the region's participation in the overall tourist traffic of Serbia are likely to increase in the future due to the region's significant natural potential and the size of its territory. The current data indicate the growth of tourism industry and the systemic approach applied to tourism development and management by the authorities of the Serbian Danube Region. At the moment, the leading municipalities in this respect are Belgrade, Novi Sad, Kladovo, Majdanpek and Veliko Gradište.
Municipalities which have the smallest tourist traffic are also the most underdeveloped. These include Odžaci, Bač, Titel and Pančevo. Thus, the local trend contradicts the global pattern in which the share of family business in tourism, especially in the domain of accommodation services, is becoming increasingly important [16]. Encouraging the construction of facilities in the private sector seems to be a very suitable development option, which could improve the poor social conditions of the local population and compensate for the lack of investment in tourism and hospitality management in Serbia. This paper analyses indicators of tourist functions that can help determine the intensity of tourism and its development in a particular destination. The analysis of four indicators is applied to determine the region's importance and participation in the overall tourist offer of Serbia. In order to present the tourist development of the region, we analysed the following indicators as of 2016: the length of stay of tourists, the functionality coefficient, the capacity utilization and the intensity of functionality [17].
Length of stay (LS) is the ratio of the number of overnight stays (NO) to the number of tourists (NT): . ⋅ If the capacity utilization is higher than 60%, the business is profitable; if it ranges between 40% and 60%, then the business is able to cover its costs to stay afloat; and if under 40%, the business is not profitable [17].

NO
The intensity of functionality refers to the volume of tourist traffic in the given location within a certain time period. It can be measured in terms of space, the number of local population or the size of accommodation capacities [17]. In this paper, we measure this indicator by using the population size: 100 , where IF is the intensity of functionality; NT, the number of tourists; and PN, the local population [7].

Results and discussion
The results of research show that the Serbian Danube Region is a well-established destination on the tourist market, which is reflected in the number of tourist visits throughout the year. The turnout is particularly intense during the summer months. We should take into consideration that an increase in the number of visitors in general could lead, in addition to positive economic effects, to the decline in the quality of tourist services and excessive pressure on the capacities of certain sites.
As Table 4 illustrates, the length of tourist stays in 2016 was quite short -on average two days. This fact can be explained by the poor state of tourism and hospitality infrastructure in Serbia, for example, the lack of available rooms and beds, accompanied by the decline in the population's purchasing power and the rising prices of services. The only exception from this trend is Odžaci, in which tourists' average length of stay was about 18 days.
The functionality coefficient for the entire region is only 1.12% due to the small number of available beds. However, even if the actual number of beds was increased, we would still have a low coefficient of functionality. This means that we should also work to improve the overall tourist offer in the region. A slightly better picture in this indicator is found in Djerdap, Sombor and Bela Crkva. In these areas, the functionality coefficient is significantly higher than the average values for the whole region -over 5% -due to better accommodation capacities. It is also obvious that the local population in these areas does not suffer from intensive construction of tourist infrastructure, which is of great importance for the sustainable development of the whole region. It is recommended that in the municipalities specializing in tourism the ratio of number of beds to the number of inhabitants should be 1.5:1 [18]. The capacity utilization indicator reflects the level of economic development and profitability. Unfortunately, its current level of 21.86% indicates the ultimate unprofitability of the local accommodation facilities.
The intensity of functionality is an indicator that shows the intensity of tourist traffic, which is estimated by using the number of tourist arrivals. This indicator in the region is comparatively low and amounts to 42.7%, which means that the negative impact of tourists on the local culture and the local identity is low. Higher values of this indicator were recorded in Kladovo, Majdanpek (Djerdap), Sremski Karlovci and Belgrade. The Serbian Danube Region is becoming an increasingly important tourist destination of Serbia, along with popular spa areas and mountain destinations. It is rich in natural and anthropogenic tourist attractions, which are underrated and deserve to be better presented in the tourist market. The region's natural highlights, which could successfully compete with their counterparts in other European countries, require additional investment into the development of their tourist infrastructure. Although the general attitude in the region is that each municipality should bear responsibility for the development of its own tourism industry, it would be more productive to foster stronger links between the municipalities. Then, more prosperous municipalities such as Belgrade and Novi Sad would also be able to boost the growth of tourism in other municipalities and thus make their eco-nomic development more balanced. This way, underdeveloped areas would become more attractive to tourists while more advanced municipalities would be able to reduce the negative impact of tourism on their environment and the population's culture and way of life. Moreover, such strategy would allow the government to redistribute the pressure on the existing infrastructure, which is overloaded in the high peaks of the tourist season. In the future, measures should be taken to preserve the region's natural beauty, to develop sustainable tourism, and to invest in creating diverse and modern tourist accommodation, transport and service infrastructure. It is also recommended to develop such areas of tourism industry as sports tourism, health and recreation, sightseeing, religious tourism and congress tourism, which are less dependent on weather conditions and can ensure stable tourist traffic throughout the year.