The number of aquatic ecosystems severely affected by human activities is rapidly increasing across the globe. Recognition of the extent of degradation of aquatic ecosystems and their services has catalyzed efforts to reverse these trends. To be successful, projects to restore or rehabilitate degraded aquatic ecosystems and their services require explicit achievable goals and regular assessments of progress toward those goals to guide adaptive management. Restoration targets are often established from knowledge of pre-disturbance or reference ecosystem states. Assessment monitoring can then include measurements of chemical and ecological criteria associated with that target. Diatoms have long been employed in assessing ecosystem degradation, particularly water quality deterioration, but there are fewer examples of their use in guiding the goals, assessment, and adaptive management of ecosystem restoration and resilience. This chapter evaluates whether diatoms provide an equally powerful tool for adaptively managing ecosystem restoration and resilience as they do for signaling ecosystem degradation. Examples of successful diatom-based restoration guidance are provided from the Florida Everglades, which is currently undergoing the largest-scale ecosystem restoration program in the world. The chapter also discusses novel approaches for building public literacy about diatoms to encourage more effective and widespread application in successfully rehabilitating and sustaining the planet’s threatened aquatic resources.
