Cumulative air pollution – synergy between different pollutants and environmental factors is one of the hardest to evaluate factors in the air quality monitoring field. The evaluation of cumulative effects is hindered by a lack of verified analytical frameworks. Currently used methods are relatively simple and use statistical models with small fixed number of pollutants in association with different factors. There is almost no one solution for direct, on-site cumulative effect measurements. The alternative is the use of Cumulative Pollution Index (CPI) method – solution designed for cumulative effect calculation from bioindication and air quality measurement data. However, this method is completely new and has never been used in the air pollution evaluation activities. Therefore, the objective of this study was to evaluate the opportunity to use CPI method as a cumulative pollution evaluation tool in air quality monitoring by doing measurements of cumulative effect in several air quality measurement stations in two cities of Latvia – Liepaja and Riga. Results show that Cumulative Pollution Index method is not only usable in air quality monitoring as a tool for cumulative effect evaluation, but can reveal new facts about air pollution and ways how it affects human and ecosystem health, – such climatic and environmental factors as humidity and temperature are more important than interactions between individual pollutants and can be considered main elements in forming of cumulative pollution impact.

The aim of air pollution monitoring is a regular and continuous collection of information on air pollution to prevent hazards influencing ecosystem and its components, including humans. Nowadays, the main technology used for this purpose is electronic sensors. As they are designed for specific measurements, a lot of important factors cannot be evaluated – various pollutants diffusion or cumulative effect, exposure, dose, and bioaccumulation. As an alternative solution – bioindication – pollution level determination from its effect on certain indicator species can be used. So far potential usage of bioindication as current air pollution monitoring network’s equivalent solution has not been studied. Therefore, the aim of the research was to assess a variety of bioindication methods for air pollution determination and their applications in air pollution monitoring. During the research, commonly used bioindication methods based on their popularity in scientific literature in 2012 were selected, as well as they were assessed using theoretical analysis method in order to determine their strong and weak points in air pollution monitoring. Research results demonstrate that current bioindication methods are not suitable for monitoring purposes. Therefore, bioindication can be combined with citizen science approach. To incorporate citizen science approach in bioindication based air pollution monitoring, development of special, for this purpose designed bioindication methodology is needed.

Environmental pollution that has been one of the key issues for decades has still not lost any of its topicality. In order to study the impact of air pollution on the growth of Norway’s spruce (Picea abies (L.) Karst.), 31 sample plots were established at different distances and directions from the pollution points in the Western part of Latvia. The plots were established starting from the year 2008 summer-autumn season and finishing with the spring of 2009. The selected stands were 32 - 171 year old and of different forest site types. The selection was used in the State Forest Service database and cartographic materials. Empirical data was obtained from each of the plots which reflected the environmental effects on the trees. To ascertain the effect of air pollution on the growth of Norway spruce, the algorithm based on additional increment to volume was used. Air pollution affects eating, regardless of age and the type of growing conditions. Pollution effects are closely related to the distance from the source.

The presented study aimed to explore the relationships between different indices of ambient ozone (O3) and tree defoliation, radial increment, and specific diversity and abundance of soil micro-arthropods, stream macro-invertebrates, small mammals (mainly rodents) in order to test the hypothesis that changes in the considered objects of forest ecosystem could be related to changes in ambient ozone concentration. The observations have been carried out on 3 integrated monitoring stations located in Aukstaitija (LT-01), Dzukija (LT-02) National Parks (NPs) since 1994, and Zemaitija (LT-03) NP since 1995. The obtained data revealed that only peak ozone concentrations (from 125 to 215 mug mE-3) had significant effect on changes in the considered components of forest biota. Radial increment and crown defoliation of Scots pine, a little lower the diversity of soil microarthropods, and the least diversity of small mammals were found to be the most sensitive to ozone exposure.