Water ecosystems, specifically freshwater ecosystems, are some of the most important resources in the replenishment and purification of water sources used by humans. They provide critical habitats for a large number of aquatic plants, fishes, reptiles, birds and mammals. They host many migratory and threatened species of birds, reptiles, and fish. To provide good water quality and ecological health demands wide-ranging, intensive research on how freshwaters respond to these threats and how they improve in relation to management and restoration measures.

This book provides a state-of-the-art review of the methods and techniques applied to measure, monitor, and preserve freshwater ecosystems. Macroinvertebrate is widely used as bio-indicators in streams and rivers, and it is usually assumed that their community composition is primarily controlled by local environmental conditions. This book opens with a chapter focused on distinctive macroinvertebrate communities in a subtropical river network. This book further focuses on water bacterial and fungal community compositions associated with urban lakes as urban lakes play a pivotal role in reclaimed water resource utilization and the development of urban environments. In the past few decades, an increasing number of man-made urban lakes used for recreation has been built around city parks in order to increase the quality of the living environment for citizens. Recently, urbanization has been improved due to the rapid industrialization in developing countries. It also explores about dynamics of bacterial and fungal communities during the outbreak and decline of an algal bloom in a drinking water reservoir. The book integrates a wide-ranging coverage of ecological mechanisms regulating the dynamics of the field rotifer population in a subtropical lake; feeding ecology and establishment of the naturally-colonized freshwater cichlid; agonistic behavior of an invasive crayfish (Macronectes-Palmeri) toward the muckalee crayfish; seasonal comparison of aquatic macroinvertebrate assemblages in a flooded coastal freshwater marsh. It also presents an ichthyological overview of freshwater fishes from Capim River, Lower Amazon Basin, Brazil. A comparison of aquatic invertebrate communities in near-shore areas with high or low boating activity is also highlighted.

The intended book will be of immense interest to the students, scientists, researchers, and other stakeholders dealing with freshwater ecology and limnology.