| Abstract | In the last century urban development resulted in a significant increase of air pollutants in urban atmosphere. The air pollutants impact water and soil quality, damage the built environment, and affect the climate and air quality. Air pollution strongly affects weathering of natural rocks and architectural stone. Weathering is a breakdown of rocks at the Earth’s surface, caused by the action of water, biological activity, and changes in temperature. Thus, there are three types of weathering: chemical, physical, and biological.
To quantify rock weathering, among many different methods, the rock tablet method is one of the most widely used. It consists of cutting rock samples in a shape that allows precise calculation of their surface and volume and exposure to the natural environment over a period of time.
In this research, the rock tablet method is used to investigate the impact of air pollution on the rock weathering rate in the Zagreb urban area. Limestone rock tablets were cleaned, dried, weighted, and exposed to the Zagreb urban environment for 6 months. The locations of the tablets were: Faculty of Agriculture (location 1), Topolovec (location 2), Špansko – Oranice (location 3). Results of the research showed that the highest average absolute denudation rates were recorded at location 1, which is located in an urban area; whereas, the lowest values of average mass loss, volume loss, and absolute denudation were recorded at location 2, which is located in a less urban area. However, research also showed that the rock tablet setting significantly impacts the weathering rate. Setting the tablets to close to any object results in creation of “shelter”, protecting the tablets from airborne particles, pollutants, and rainfall, thus directly impacting weathering and denudation rates. |
