The aquatic ecosystem is a major subdivision of the biosphere, and covers almost 71% of the earth’s surface area. Coastal ecosystems mainly include estuaries, deltas, lagoons, mangrove forests, mudflats, salt marshes, salt pans, other coastal wetlands, ports and marinas, aquaculture beds, sea grass beds, coral reefs, and soft bottom environments above the continental shelf. Although coastal ecosystems represent only a small area of the world’s oceans, they are of great ecological and economic importance. Now-a-days, many of the coastal ecosystems of the world are being exploited for various development projects, resulting in deterioration of habitats and resources. Therefore, the present study focuses on two of such important coastal ecosystems such as estuary and mangrove. Estuary is a dynamic area with varying physical and topographical conditions, with neritic province, river delta, lagoon, backwater, mangroves, mudflat, and salt marsh, all being part of this vital area. Estuaries are important areas of human use for fisheries, transportation, aquaculture, and recreational pursuits. Thus, by virtue of their natural location and easy accessibility, estuaries are more amenable to anthropogenic influences. Mangroves are specialized ecosystems developed along estuarine seacoasts and river mouths in tropical and subtropical regions of the world, mainly in the intertidal zone. Hence, the mangrove ecosystem and its biological components are under the influence of both marine and freshwater conditions and have developed a set of physiological adaptations to overcome problems of anoxia, salinity and frequent tidal inundations. This has led to the assemblage of a wide variety of plant and animal species of special adaptations suited to the ecosystem. The book Pollution Status of Coastal Environment of Gulf of Khambhat, India covers an extensive study at Mahi Estuary and Vamleshwar Mangroves (Gulf of Khambhat), Gujarat, India. The authors have explored hydrochemistry, geochemistry, phytoplankton, zooplankton, and benthic community, along with site-specific conservation and their management strategies in both the marine environs. The book will be a ready reference to academicians, scientists, students, researchers, and marine authorities of the State as well as the Country, to enhance the knowledge in the field of mangroves and estuarine ecology, biodiversity, conservation, restoration, and management.