Unsanitary landfills and inadequate waste management system represent the 3^rd largest global anthropogenic source of methane emissions in the environment. Waste management system in Novi Sad, the second largest city in Serbia, significantly contributes to the national carbon footprint. Unsanitary Municipal solid waste landfill in Novi Sad receives and deposits mixed waste without any treatment, thus causing the organic waste to biodegrade within the landfill body, and produce and emit the landfill gas (mostly CH₄ and CO₂) in the environment. Other potential sources of greenhouse gas emissions from waste management system include vehicles used for waste collection, machinery used at the landfill and landfill fires. The purpose of this study is to determine total baseline emissions of relevant greenhouse gases from the waste management system in Novi Sad, and to estimate and quantify the emission reduction potential for defined organic waste treatment scenario. The potential scenarios for organic waste diversion and treatment from the landfill include composting, anaerobic digestion, mechanical biological treatment, waste to energy, etc. Quantification of baseline emissions and climate change mitigation potential are estimated using the Solid Waste Emissions Estimation Tool, the model developed by Climate and Clean Air Coalition.

The aim of this work was to determine the most relevant pollutants in Danube surface water and wastewater in the city of Novi Sad, and to conduct a risk assessment approach on substances for the optimization of future monitoring programmes. According to the requirements of Serbian law, obligatory and operating monitoring was focused on physico-chemical and biological parameters while the expanded monitoring programmes have not been applied – often due to practical circumstances. Novi Sad, with a population of more than 300.000 inhabitants, does not have a wastewater treatment plant, and about 2 m³ of wastewater is discharged directly to the Danube river every day. Screening analyses of the water within the Danube basin around city of Novi Sad included more than 300 different organic substances, while target analysis was conducted for all WFD pollutants. The methodology for generating the list of priority substances was applied for the first time in the Danubian region around the city of Novi Sad. By applying the prioritization procedure, 86 organic substances were determined in screening analyses and 27 substances obtained within target analyses were identified as the most relevant. In addition, seasonal variation analysis was conducted to determine the occurrence trends of specific compounds in different seasons.

Common practice in Southeast Europe (SEE) countries is that mostly low skilled workers work in waste management sector. In SEE countries there are no institutions specialized for educational training concerning safety of the employees who work in solid waste management system. It should be emphasized, that this specific type of profession, which is dealing with the high occupational health risks, needs legal basis for proper education and training, like it is defined for numerous professions in public sectors. Evidently, companies that provide the education and training for their employees will have direct benefits. The main focus of professional education is on workers on landfill, as this is the working place with the highest risk, but at the same time very important for operational practice and sustainability of a landfill. For these workers, there are following focus points: Professional training; Health and Safety protection; Fire protection; Landfill gas management; Leachate management. Well defined educational programmes for H&S, emphasizing safety precautions in handling with hazardous materials and fire protection, are good way to reduce injuries and to improve efficiency of employees as well.

The sustainable management of water resources requires experts and also citizens who understand the hydrosphere and its key functions. To educate the public about water-related issues, various water literacy concepts have been developed. However, many of these concepts are too complex for people to understand. In contrast, the ocean literacy framework effectively translates knowledge into behavioral changes and actions. The Danube River, known as the world’s most international river, has a catchment area shared by 19 countries. This river basin has experienced unprecedented landscape alterations, floods, droughts, and pollution events, highlighting the need for a new approach to environmental education. Additionally, globally, more people live near rivers than by the ocean. To empower members of riverside communities with water literacy, we aimed to adapt the ocean literacy principles into river literacy principles. In this study, we introduce a novel concept of river literacy, consisting of seven principles. This framework aims to support sustainable development goals through education and to restore and revive damaged freshwater habitats more effectively. The principles were tested in formal education across five countries. The results indicate that participants in river literacy programs became more motivated to protect rivers, and their understanding of fluvial geography and riverine pollution improved.

The first case of COVID-19 infection in Serbia was confirmed in early March 2020. State of Emergency was declared soon afterward, imposing shelter in place measures and curfew in the evening hours. A number of countries around the world have experienced air quality improvements during the pandemic, caused by the mandatory quarantine. This study aims to analyze the effect of the quarantine on the air quality, by comparing PM2.5, PM10, and NO2 concentration levels during 32 days quarantine period in the six cities in Serbia, from March 16 to April 16, 2020, with values obtained in the same period in 2019. NO2 concentration levels showed significant reductions in all cities (36-71%). However, PM2.5 and PM10 concentration levels did not show significant reductions in all cities. Concentration levels of PM2.5 and PM10 were lower during the quarantine period only in two cities, by 2 and 19%, and 10 and 30% respectively. Analyzed values can assist decision-makers in defining the levels of effort and scope of actions that need to be undertaken in order to prevent the occurrence of high levels of concentration of PM2.5 and PM10 and to ensure clean and healthy air in Serbia.

In the past protection of human health and safety represented the main reasons for waste management. Protection of human health and the environment, even today, stands as the purpose of waste management. Increased transformation of materials highly influences the waste management system. Transformation of materials for prehistoric men amounted up to 5-6 tons per year, while for modern men today it goes up to 80-90 tons per year. Such level of material use led to the fact that around 1.2 billion tons of municipal waste has been produced in the world annually. Therefore, today it is not enough to protect human health only through adequate management, but it is also necessary for waste management to be sustainable. In developed countries, where it is possible to use significant financial resources, the most common are sophisticated techniques, such as incineration, while in developing countries potential solutions are sanitary landfills with possible implementation of MBT, due to the fact that incineration, even though it is probably the best solution, can hardly be implemented in developing countries due to the high operational cost. Recycling is very popular, but only recycling could solve not all problems. Landfilling, as the final sink of numerous materials will definitely subsist in undeveloped and developed countries as well, since it represents the basis of waste management system and numerous researches have been focused on landfills as final destination of materials we use or transform through various types of waste treatment. Serbia is currently in process of joining European Union, and together with development of entire society and the economy, adequate development of waste management system is also very important. As country in transition with 3582 landfills and annual production of 0.87 kg capita-1 day-1, and very tough economic situation, Serbia seeks for solution of problem with waste. Kuznetov's curve confirms that it is impossible to skip certain steps in the development of the waste management system in undeveloped countries, which means that transition countries will have to find less expensive solution to waste management problems. Right orientation and direction of scientific research towards the regulation of this area regarding management system and finding affordable and applicable technologies, can make such research up-to-date in developed countries, where landfilling has been overcome.