To achieve the highest possible agricultural production, it is necessary to procure the appropriate agricultural machinery. A tractor is the most useful machine in agriculture that performs various functions. Therefore, the selection of a tractor is one of the key decisions in the agriculture-production process. This study aims to evaluate heavy tractors for agricultural production in Bosnia and Herzegovina. Since this is a selection between different tractors, which are evaluated using several criteria, the methods of multi-criteria analysis (MCDA) were used in this study. Five different methods were used to determine the weight of the criteria, of which a modified standard-deviation method is a new method used in practice, while the tractor ranking was performed using the CRADIS (compromise ranking of alternatives from distance to ideal solution) method. The results showed that the best-ranked tractor is A4, while the most deviations from the ranking occur when the entropy method is used. The contribution of this study is in the systematization of the methods for the objective determination of the criteria weights and the development of new methods to facilitate decision-making in agriculture and other industries.

The Deliblato Sands Special Nature Reserve (SNR) is located in the Autonomous Province of Vojvodina (Northern Serbia). The favorable position implies the proximity to large cities with which it has good traffic connections. Romania, Hungary, Bulgaria, Croatia, and other countries from the region represent a dispersive zone. The topic of this paper is the function that the SNR has in sustainable tourism development. The objective of this work is the analytical research of the available written data, as well as those obtained after the conducted survey. The basis of the research is to find out how and to what extent the SNR contributes to sustainable tourism development. The research was carried out by measuring the value of sustainable tourism indicators, and examining the attitudes of residents, visitors, and students about the current state of sustainable tourism and the importance of the SNR for future tourism development. Respondents were selected using a random sample method. The authors used qualitative and quantitative methodologies in the paper. This research examined the SNR sustainable development by measuring sustainability indicators and surveying 1884 respondents (714 residents, 620 visitors, and 550 students) about sustainable tourism in the SNR. The obtained data were analyzed and presented with the help of SPSS v. 21 software. The research results can be used to create national and international strategies for sustainable tourism development.

The sustainable development of tourism in protected areas and the planning of its development is extremely important for mountain regions. The local population and tourists have a very important role in this process. Therefore, surveys of the local population and visitor satisfaction represent the basis of this research. The Vršac Mountains Outstanding Natural Landscape (ONL) could represent a significant destination for sustainable tourism. This mountainous area is characterized by a favorable geographical position, a diversity of natural and social factors, rare flora and fauna, and the rich ethno-social heritage of the local population. It is in a very favorable geographical position, and the proximity of the big cities Serbia and Romania, as well as many other factors, are important for tourism development in this area. A quantitative methodology was used for the purposes of this paper during our research. The purpose of this research was to investigate the influence of tourism development on the satisfaction of residents and visitors of the ONL by applying a survey technique, with the help of a questionnaire as a research instrument. A total of 1419 respondents were surveyed (789 residents and 630 visitors). The research results show that the ecological and socio-cultural dimensions of sustainability have the greatest importance for the respondents, and that these two dimensions of sustainability have the greatest impact on sustainable tourism in this protected area. Our main research hypothesis, which states that sustainable tourism has a positive impact on the satisfaction of residents and visitors, is fully confirmed. These data could be significant for tourism planning and the management of protected areas.

This research analyzed the degree of utilization of the agricultural biomass for energy purposes (combustion), in order to indicate the reasons that limit its use. The biomass potential was studied by means of the methodology of the biomass potential, whereas the factors suggesting a low degree of biomass utilization were identified by means of factor analysis. The research results reveal that there is an enormous potential of the unused agricultural biomass. This dissertation research significantly contributes to the establishment of a genuine mathematical model based on multiple linear regression. The solution obtained by this analysis, in both a mathematical and a scientific manner, conveys the primary reasons for an insufficient utilization of the biomass for energy purposes. Moreover, the paper suggests the measures to be applied for a more substantial use of this renewable source of energy and presents the expected benefits to be gained.

The Nature Park Ponjavica (NP) is the habitat of strictly protected plant and animal species, located in AP Vojvodina, in southern Banat (Northern Serbia). The area of the park covers 302.96 ha. Protection zones I, II, and III have been established in the protected area of the NP. The NP includes the middle course of the Ponjavica River, which has preserved characteristics of watercourses of plain areas and coastal remains of wetland habitats. The most valuable area of this park in terms of protection is an island with an area of slightly less than 1 hectare. According to the IUCN (International Union for Conservation of Nature), the NP is classified as the fourth category—Habitat and species management area. The good geographical position of NP is one of its main characteristics. The NP can be a destination where specific forms of tourism can be developed, such as ecotourism, nature-based tourism, birdwatching, scientific and research tourism, etc. Numerous historical sites represent a significant potential for the development of cultural tourism. The research examined the influence of institutional, economic, ecological, and socio-cultural sustainability on the respondents’ satisfaction. The quantitative methodology in this research included a questionnaire as a survey instrument for respondents. A total of 547 residents were surveyed. The results of the research indicate that there is considerable satisfaction among residents with sustainable tourism. The results of the research can help in the development of numerous tourism development strategies in which the wetland is the primary resource.