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Phosphorus (P) as an essential nutrient for life sustains the productivity of food systems; yet misdirected P often accumulates in wastewater and triggers water eutrophication if not properly treated. Although technologies have been developed to remove P, little attention has been paid to the recovery of P from wastewater. This work provides a comprehensive review of the state-of-the-art P removal technologies in the science of wastewater treatment. Our analyses focus on the mechanisms, removal efficiencies, and recovery potential of four typical water and wastewater treatment processes including precipitation, biological treatment, membrane separation, and adsorption. The design principles, feasibility, operation parameters, and pros & cons of these technologies are analyzed and compared. Perspectives and future research of P removal and recovery are also proposed in the context of paradigm shift to sustainable water treatment technology. P removal efficiencies and P recovery potential of four typical wastewater treatment processes are critically reviewed. Feasibility, transfer routes, operation parameters, and pros & cons of these technologies in P recovery are analyzed and compared P can be recovered from wastewater into value-added fertilizers or soil amendment. Perspectives and future research directions of P removal and recovery are outlined. [ABSTRACT FROM AUTHOR]

Recent advancement in molecular techniques has spurred numerous studies on responses of microorganisms to lead exposure, leveraging detailed phylogenetic analyses and functional gene identification to discern the effects of lead toxicity on microbial communities. A comprehensive review of recent research is provided on (1) lead resistance mechanisms of microorganisms; (2) microbial community changes in contaminated aquatic sediments and terrestrial soils; and (3) lead resistance genes applied to lead biosensor development. Ample evidence in the literature, including both in vitro and in situ studies, indicates that exposure to lead inhibits microbial activities (such as respiration and metabolism), reduces biomass and alters microbial community structure. Even at sites where microbial communities do not vary compositionally with contaminant levels, functional differences between microbial communities are evident. The main mechanisms of lead resistance involve extracellular and intracellular biosorption, precipitation, complexation, and/or efflux pumps. The suites of genes associated with lead resistance mechanisms can serve, when considered with phylogenetic information, as indicators of lead contamination. This holds potential for development of next generation lead biosensors. To promote applications of advanced knowledge, molecular techniques, and lead biosensor technology, perspectives on using microbial indicators for site ecological assessment are presented. [ABSTRACT FROM AUTHOR]

Alginate-based composites have been extensively studied for applications in energy and environmental sectors due to their biocompatible, nontoxic, and cost-effective properties. This review is designed to provide an overview of the synthesis and application of alginate-based composites. In addition to an overview of current understanding of alginate biopolymer, gelation process, and cross-linking mechanisms, this work focuses on adsorption mechanisms and performance of different alginate-based composites for the removal of various pollutants including dyes, heavy metals, and antibiotics in water and wastewater. While encapsulation in alginate gel beads confers protective benefits to engineered nanoparticles, carbonaceous materials, cells and microbes, alginate-based composites typically exhibit enhanced adsorption performance. The physical and chemical properties of alginate-based composites determine the effectiveness under different application conditions. A series of alginate-based composites and their physicochemical and sorptive properties have been summarized. This critical review not only summarizes recent advances in alginate-based composites but also presents a perspective of future work for their environmental applications. [ABSTRACT FROM AUTHOR]

Planning and implementation of unprecedented projects for restoring the greater Everglades ecosystem are underway and the hydrologic and hydrodynamic modeling of restoration alternatives has become essential for success of restoration efforts. In view of the complex nature of the South Florida water resources system, regional-scale (system-wide) hydrologic models have been developed and used extensively for the development of the Comprehensive Everglades Restoration Plan. In addition, numerous subregional-scale hydrologic and hydrodynamic models have been developed and are being used for evaluating project-scale water management plans associated with urban, agricultural, and inland costal ecosystems. The authors provide a comprehensive summary of models of all scales, as well as the next generation models under development to meet the future needs of ecosystem restoration efforts in South Florida. The multiagency efforts to develop and apply models have allowed the agencies to understand the complex hydrologic interactions, quantify appropriate performance measures, and use new technologies in simulation algorithms, software development, and GIS/database techniques to meet the future modeling needs of the ecosystem restoration programs. [ABSTRACT FROM AUTHOR]