The present book discusses the use of lichen as a biomonitor tool to trace element air deposition, especially focusing on their accumulation performance. The work comprises three main parts, each one addressing relevant issues on factors influencing bioaccumulation. The distribution of accumulated elements, the lichen parameters that need to be used in assessing and ensuring comparability of their characteristics in space and time and the dynamics of the elemental accumulation and release in lichens are all subjects covered in depth in this volume. Lichen Biomonitors: Factor Affecting Response Behaviour starts by presenting the current state of the art of biomonitoring and by introducing relevant issues both generally and specifically recognised as needing attention. The work goes on to explain the intercellular distribution of elements in lichens, the procedures of the comparability testing experiment and, finally, the study of lichens dynamic in more detail. The final chapter discusses and summarises the principal work and the conclusions of the different experiments of the study and highlights the future research that is needed in this area. This book is a must have for people working on biomonitoring issues offering an in depth study particularly in lichen, for those interested or that have previously worked with these organisms.