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This research analyzes the use of natural shrimp shell and commercial chitin for biosorption of metal ions in surface runoff. Investigation of the use of these biosorbent materials in drainage systems becomes a management measure for two extremely important issues in Brazil, fish waste management and the surface runoff quality. Methodological procedures involved treatments with different amounts of unprocessed shrimp shell and commercial chitin (5g and 10g) for 200mL of a compensatory drainage mechanism (infiltration swale). The contact time of biosorbent and runoff was 24h and removal of metal ions Fe, Mn, Zn, Cu, Ni, Pb, and Cr was studied. Tests with unprocessed shrimp shell showed high concentrations of metallic ions (Pb, Ni, and Cu) causing contamination of the environment. However, the two biosorbents presented good removal of specific metallic ions (Fe, Mn, Zn, and Cr). These results indicate the need for a biosorbent pre-treatment prior to full-scale use. We indicate the need for a more detailed investigation of water quality in the environment used for shrimp farming. Tests with commercial chitin presented satisfactory results for two concentrations tested. Tests with 10g of commercial chitin allowed removal of all tested metal ions (Fe, Mn, Zn, Cu, Ni, Pb, Cr) with removal percentage between 6.7% and 84.4%. This efficiency may be related to the chitin's composition (shrimp, crustaceans, and crab) and to the chemical process applied to the product prior to commercialization.

The use of biocementation is a technique widely used in the civil construction to repair pathologies, such as cracks and fissures. This technique is linked to the bacterial activity (urolytic and/or carbonategenic), responsible for the conversion of urea into carbonate, correcting problems in the structure. In this sense, the aim of this study was to identify the main ureolytic bacteria capable of precipitating calcium carbonate in mortar, one of the most widely applied construction areas, as well as to evaluate the performance of each microorganism in changing the physical and mechanical properties of the mortar. For this, a bibliographic search was carried out in the database of Scopus, Scielo, Web of Since, as well as in the academic portal of CAPES. The results show that the main bacteria associated with the mortar biocementation technique is the genus Bacillus sp. Parameters and standards for evaluating the performance of the different bacteria used between the studies were not identified. However, evaluations related to mortar strength were present in the vast majority of researches. The use of biocementation via bacterial activity proved to be an important strategy that promotes improvements in strength, compression, water absorption potential and porosity of the mortar

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