"Based on the latest UGC Curriculum, the first edition of Environmental Studies has been thoroughly revised and updated. Environmental studies as a scientific discipline is an emerging area with enormous potential. The increase in population has required rapid industrialization and further urbanization. This has caused great damage to water, air and environments. Every citizen must know the natural state of the environment, its ability to adapt and its abuses and consequent problems. So the environment has become a compulsory subject at the graduate and undergraduate level in the Universities, Colleges & Institutions. Technological progress has often led to environmental damage. Expeditious industrialization, growing population and the resulting wanton exploitation of scarce resources have led to urgent environmental problems such as desertification, deforestation, the clean water crisis, acid rain, depletion of the ozone layer and global warming. Realizing the threats ahead in life support systems, the focus has now shifted to sustainable development. Obviously, this cannot be achieved without the involvement of masses from all walks of life, scientists, academics, social scientists, and policy makers, so they must be familiar with the Environmental science, their interaction with human activity, and ways and means of living together. This book entitled Environmental Studies has been written specifically for graduate students from the University, Colleges, and institutions. Its aim is to present all scientific fundamentals in an easy-to-convert, comprehensive, and lucid way. This book also designed the environmental systems well. It also emphasizes the connections between the different specialty areas of Environment, Renewable and Non-renewable Resources, Ecology, Ecosystem, Biodiversity and its importance, Wastewater treatment, Engineering of air quality, waste management, hazardous waste management and its remediation, socio-legal and moral aspects involved in man-environment interactions. I would like to thank my parents for all the sources used directly or indirectly for the teaching material and the consequences. Thanks go to my well-wishers who helped me with this attempt. The exercise suggestions for improving and changing the teaching material and the sequences for the text are very welcome in the hope that the book will prove useful for students and educators. I look forward to your important feedback."