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.

This article presents the description of oak woodland key habitats and their importance in the maintaining of biodiversity as well as a necessity of management and monitoring. The lichens Lichenes and its percental cover features have been described. The exposition of lichen species depending on the cardinal points has been analysed. The article presents the characteristics of ecological indicators of lichens in the objects. The lichenoindicative evaluation and comparison of oak woodland key habitats in Latvia have been carried out.

The main pine natural woodland habitats (woodland key habitats -WKH) and the importance of their management and monitoring have been described in this paper. The ecological importance of lichen epiphytes in forest ecosystem has been analysed. The lichenoflora and its percental cover features have been described. The exposition of lichen species depending on the cardinal points has been analysed. The paper presents the characteristics of ecological indicators of lichen in the landscape features. The lichenoindicative evaluation and comparison of pine WKH have been carried out.

The emergence of human–induced edges in forested landscapes has caused major threat for the existence of habitat specialists. Woodland key habitat (WKH) concept has been created in the Baltic and Fennoscandian forests to preserve small forest parcels with a high biodiversity value in the production forests. In this study we investigated the occurrence of epiphytic lichen indicator species in black alder WKHs in Southern Latvia. In total 30 black alder WKHs with age of 84 to 129 years were chosen for analysis including stands adjacent to young, middle–aged and mature stands. Sample plots were placed at three distances from the forest edge. Our results indicate significant differences in number of species per sample plots adjacent to stands of different age. Lichen indicator species were considerably more common in habitats adjacent to mature forest stands and further (40–50 m) from the edge. From four lichen indicator species found in this study, sample plots adjacent to young stands hosted only two species. We argue that the indicator species response to human–induced edges is species specific and some of them are resistant to microclimatic changes near the edges.