The Yangtze River estuary is a system where geological, biological, and socioeconomic processes actively interplay. The Yangtze River carries about 5 billion tons of sediment to the estuary from upstream each year, providing rich substrates for biological activities and alluvial processes. An exotic plant species, Spartina alterniflora was intentionally introduced to the region in 1979, and has aggressively invaded the Yangtze River estuary and coastal China. The biological invasion alters plant and animal biodiversity and ecosystem processes. In addition, the Yangtze River estuary is close to Shanghai, one of the most economically active cities in China and the world. Fast economic development and social transformation exert great pressure to exploit resources in the estuary. In the last few decades, scientists from several leading universities in China have conducted research on many of geological, biological, and socioeconomic processes. An increasing number of papers have been published in international journals. This volume comprehensively synthesizes the lessons learned from various groups. This text not only provides a new example of ecosystem studies on estuary systems, but will also serve as a milestone to promote the management of this important region that will produce global impacts. Moreover, the book can be used as a reference book for ecological research in estuarine ecosystems of major rivers, such as the Mississippi and Amazon Rivers.