Assessing Sustainability of Shrimp Aquaculture and Integration with a Field Crop

Assessing Sustainability of Shrimp Aquaculture and Integration with a Field Crop

Summary

A field study utilizing a randomized block design was conducted to test the effect of three low-salinity shrimp farm effluent/well water/fertilizer combinations on olive tree growth. Trees were flood-irrigated every 10 to 12 days. Irrigation water was analyzed for TN, NO3-N, TP, K and EC. Additionally, tree growth, soil salinity and soil macronutrients were monitored. Statistical differences in TN and K were found in the irrigation water, however, no differences were observed in tree growth. While growth of trees irrigated with effluent did not improve in respect to the other treatments, no noticeable negative effects were observed.

Objectives/Performance Targets

• Determine the benefits of irrigating with aquacultural effluents

  Determine any detrimental effects on soils

  Reduction of reliance on chemical fertilizers

  Efficient utilization of scarce water resources

  Organize an aquaculture field day to initiate an integrated aquaculture/agriculture extension program in Arizona

Accomplishments/Milestones

• Determine the benefits of irrigating with aquacultural effluents – Unforeseen problems were encountered during the first year of fieldwork. Specifically, farm management decisions impacted the test plot irrigation plan, calling into question the scientific value of the findings. As a result, a new trial is being conducted. Results from the first year, while questionable, indicate that irrigating with shrimp farm has neither a significant benefit or detriment to olive trees.

  Determine any detrimental effects on soils – Preliminary results indicate that soil salinity has not increased as a result of irrigating with low-salinity shrimp farm effluent. Results from the remaining years of the project are expected to bear this finding out.

  Reduction of reliance on chemical fertilizers – As growth trial results are incomplete at this time, the reduction in reliance on chemical fertilizer that can be expected as a result of this integrated approach has not yet been quantified.

  Efficient utilization of scarce water resources – The practice of using aquaculture effluent as a source of irrigation water is currently being used on most of the shrimp farms in Arizona and many of the fish farms. This practice effectively eliminates effluent discharge from aquaculture operations in Arizona and provides farms with a greater economic return per unit of water pumped.

  Organize an aquaculture field day to initiate an integrated aquaculture/agriculture extension program in Arizona – In May of 2002 an aquaculture extension field day was held at the University of Arizona, Maricopa Agriculture Center. The meeting was attended by 55 participants, including producers, educators, students, county extension agents and vendors. Additionally, an Arid Lands Aquaculture session was chaired by Dr. Kevin Fitzsimmons at the World Aquaculture 2002 meeting in Beijing, China and presentations were made by Dennis McIntosh and Dr. Fitzsimmons related to this project.

Impacts and Contributions/Outcomes

Since the implementation of this project, interest in integrated aquaculture/agriculture systems has increased significantly. We continue to work closely with our farmer cooperator and in addition, have had an opportunity to work directly with the other three shrimp farms in Arizona. As the aquaculture extension specialist for Arizona, Dr. Fitzsimmons receives at least one call each week seeking information on integrated aquaculture/agriculture. Calls come from agriculture and aquaculture producers looking for ways to integrate their farms and maximize the on farm efficiency; from potential investors seeking information on sustainability of integrated shrimp farms in the southwest; and from educators looking for ideas to use to teach biology and environmental management to their students.

As indicated by the attendance at the aquaculture field day, producers and consumers alike see the benefit of integrating aquaculture and agriculture. Integrated aquaculture/agriculture production has the potential to reduce on farm production costs by increasing water use efficiency while simultaneously eliminating aquaculture effluent disposal concerns. As governmental regulations tighten and consumers become more interested in environmentally benign production of their food, this practice of integrating aquaculture production with traditional agriculture will become increasingly more prominent.

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