Preface

The volume Soil Heavy Metals duly edited by Irena Sherameti and Ajit Varma, published in 2010, was a success story. This was nicely celebrated in typical German style in the house of Professor Dr. Ralf Oelmüller, Institute of General Botany and Plant Physiology, University of Jena. Over a glass of wine I proposed to Irena to edit a volume on detoxification of heavy metals in soil. After a short discussion, we agreed to work together on this volume. This volume summarises the ongoing scientific activities in the field of detoxification of heavy metals in soils, plants and microorganisms. The chapters are arranged in such a way that first we get an introduction about the art of detoxification of heavy metals and the heavy metal plants. The second group of chapters deals with the phytoremediation in general and phytoremediation of special ions. The next section describes several aspects of plant responses to heavy metals and the responses of special organisms/groups to heavy metals. At last different methodologies for detoxification of heavy metals in soils and plants are discussed. Soil, one of the most important natural resources, is becoming degraded due to anthropogenic activities such as mining, agricultural activities, sewage sludge, fossil fuel combustion, metallurgical and chemical industries and electronics. As described in Chap. 1 written by Jyoti Agrawal, Irena Sherameti and Ajit Varma each source of contamination has its own damaging effects to plants, animals and humans, but the pollution from heavy metals is of serious concern and a big potential threat to the environment and human health. This chapter gives a general overview of some of the sources of heavy metal contaminants in soil, soil–plant relationships regarding heavy metals and heavy metal tolerance mechanism(s) in plants. In Chap. 2, Hermann Bothe directs us to the heavy metal soils and heavy metal plants (Metallophytes) of Central Europe showing that the adaptations of these metallophytes to the adverse conditions of heavy metal soils differ from one plant species to the next. Further we get introduced to some strategies employed by the metallophytes to cope with high concentrations of heavy metals at the whole plant level and gene expressions upon heavy metal stress in plants. Functional significance of metal ligands in hyperaccumulating plants is analysed by Marjana Regvar and Katarina Vogel-Mikuš in Chap. 3. This chapter focuses on ligands (organic acids, histidine, metallothioneins, low-molecular-weight thiols, etc.) that