Brunno Cerozi

Brunno Cerozi is a Ph.D. student in the Department of Soil, Water and Environmental Science and the recipient of the Best Research Presentation at “Grad Blitz” held on the UA campus Nov 3, 2015.

Brunno also represents the Science without Borders program of Brazil and is a 2014 Institute of the Environment Carson Scholar.

Brunno received his B.S. degree in agronomy and his master's degree in animal science from the University of São Paulo. His research area, both past and present, is in the field of aquaculture.   He decided to come to Arizona to study aquaponics, a more sustainable way of producing fish and plants together in a soil-free hydroponic integrated system, in which nutrients and water are constantly recycled. His Ph.D. research is specifically describing the phosphorus dynamics, mass balance, and alternative ways of enhancing phosphorus availability in an aquaponics system. He is raising tilapia and growing lettuce and tracing inputs, partitioning, and outputs of phosphorus through the system. His advisor is Dr. Kevin Fitzsimmons.

The Environmental Grad Blitz, sponsored by the Institute of the Environment, is designed to bring together graduate students working on environment-related research and arts to showcase their research findings and creative works. The event provides a special opportunity for students to share their work with students, faculty, university administrators, and others.

A number of judges are members of the community and selected because they are not scientists.

The format for the oral presentation is a a five-minute speed talk, including no more than three slides. The criteria for judging include:

  • Was the overall significance of the research clearly conveyed?
  • Were the methods clearly described?
  • Did the stated conclusions follow from the presented research?
  • Was the presentation speaker style (and slides if used) clear and easy to follow?
  • Did the speaker stay within the allotted time limit? (5 min)


More information about the Blitz and all of the winners can be found at


Title and Abstract of Bruno’s award winning  presentation:

Phosphorus Dynamics Modeling and Mass Balance in Aquaponics Systems

Phosphate rock, a limited natural resource, has been the exclusive economical source of phosphorus in the manufacturing of phosphate fertilizers. Mining and beneficiation of phosphate rock are highly energy intensive processes that potentially result in a wide variety of adverse environmental effects. The dependence of fertilizer production on fossil energy source and the prospects of diminishing availability of costly input of fertilizer production in years to come, have made imperative the search for alternative phosphorus sources. Aquacultural effluents are known to be rich in phosphorus (P) and nitrogen (N), being a growing concern worldwide due to their potential for environmental pollution. Hence integrating aquaculture with agriculture, e.g. aquaponics, has potential to enhance nutrient and water use efficiency and overall environmental sustainability. Little is known about the dynamics and mass balance of phosphorus in aquaponics. It is important to understand nutrient absorption dynamics in order to adapt inputs to extraction rates. Thus, this trial was conducted to quantify a P flow and a P budget by using a nutrient mass balance equation and evaluate P production, loading, and removal efficiency of hydroponic lettuce integrated with tilapia aquaculture in aquaponics systems. 15 tilapia juveniles (20g) and four 15-day-old lettuce seedlings comprised each aquaponics experimental unit (n=3). Fish were fed 1% of their biomass per day. At days 0, 7, 14, 21 and 28 after transplanting, water samples were taken from each aquaponics biofilter to determine reactive and total concentration of phosphorus. Lettuce, fish and feed samples were oven dried and ground for P content analysis. The P dynamics model was validated by comparing simulated to observed values of dissolved P over time. The linear regression equations between simulated and measured values were compared with the 1:1 line for statistically significant differences (p < 0.05) in slope and intercept values. The adequacy of the model was determined by testing if intercept equals zero and slope equals one separately using the one sample Student T-test. Comparison of simulated and measured values of dissolved P dynamics showed a good fit around the 1:1 line with the slope (b = 1.005) and intercept values (a = 0.0189) being not statistically different (p > 0.05) from 1.0 and 0, respectively. The assimilation of P in the fish and plant components comprised 74.2% of the total P input, indicating high P utilization by the system. The P dynamics model predicted the behavior of dissolved phosphorus in aquaponics systems, which can be used to determine adequate fish:plant ratios, maximize P use efficiency and minimize waste. The overall high P utilization by fish and plants determined in this study showed that aquaponics is a great tool to recycle phosphorus, reducing environmental pollution and pressure on natural phosphorus reserves.


Brunno Cerozi

PhD Student

Department of Soil, Water and Environmental Science
1177 E. Fourth Street, P.O. Box 210038
University of Arizona
Tucson, AZ 85721-0038
Phone:  (520) 369-1007