Dr. Indrajeet Kumar is an Assistant Professor in the Department of Botany at Govt. Degree College, Pawanikala, Sonbhadra, India. He received his B.Sc. (Hons.), M.Sc. and Ph.D. degrees in botany from the Banaras Hindu University, Varanasi, India. His research interests focus on natural bioactive compounds, value addition strategies, sustainable agricultural waste management, and the impact of abiotic stresses on plants. He is also engaged in environmental risk assessments and exploring ecofriendly approaches to resource utilization. Dr. Kumar has contributed extensively to scientific literature in reputed national and international journals, as well as by authoring book chapters in edited volumes, reflecting his active involvement in advancing knowledge in plant sciences, environmental sustainability, and natural product research. Dr. Rajesh Kumar Sharma holds B.Sc., M.Sc., and Ph.D. degrees in botany from Banaras Hindu University, Varanasi, India. He has served as a senior scientist (2008–15) at the G. B. Pant National Institute of Himalayan Environment, where he worked on ecological and health risks from heavy metals and pesticide residues in mountain ecosystems, pollutant remediation,and phytochemical analysis of medicinal plants.Currently, he has been serving Banaras Hindu University as an Assistant Professor since 2015. A prolific researcher and author, his current research investigates the environmental toxicity of metals and metalloids and of pesticide residues, and explores remediation strategies using plants, microbes, and waste-derived biochar and bioash. Dr. Prince Kumar Singh is a research scholar at the Department of Botany, Institute of Science, Banaras Hindu University, Varanasi, India. He has completed his M.Sc. and Ph.D. degrees in Environmental Science from Banaras Hindu University, Varanasi, India. Dr. Singh has 7 years of research experience in the fields of ecology and environment. His long-term research goal is to advance understanding and address critical challenges in contaminant flux, fate, andtransport of heavy metals, while promoting sustainable practices in agriculture, waste management, ecotoxicology, and risk assessment. Dr. Singh has published research articles in nationally and internationally reputed journals and has also contributed chapters to edited books. Eric D. van Hullebusch is a Full Professor in Biogeochemistry of Engineered Ecosystems at the Institut de Physique du Globe de Paris, Université Paris Cité, France. He holds a Ph.D. in Aquatic Chemistry and Microbiology fromUniversité de Limoges. After a Marie Curie fellowship at Wageningen University & Research, where he worked on optimizing anaerobic sludge reactorswith respect to trace metalspeciation and bioavailability, he was appointed Associate Professor in 2005 at Université Gustave Eiffel. A very prolific researcher and author, his key interests lie in the biogeochemistry of metals and metalloids in engineered systems, pollutant remediation, and circular resource recovery through biohydrometallurgical techniques. He is especially focused on sustainable strategiesfor waste treatment, soil remediation, and recovering technology-critical elementsfrom agricultural and industrial wastes.
