Use of Shrimp Sludge as a Soil Amendment for Tomatoes

1. Use of Shrimp Sludge as a Soil Amendment for Tomatoes Chad King, Kevin Fitzsimmons, Dennis McIntoshEnvironmental Research LabUniversity of Arizona

2. Purpose • Determine feasibility of use of shrimp sludge from low salinity inland shrimp culture as a soil amendment. • Apply sludge at disposal rates, not to meet plant requirements. • Provide a use or disposal for a current waste product • Reduce the potential for farm erosion, nutrient leaching/loss

3. Research Design • Collected and dried fresh sludge from a shrimp farm in western Arizona, USA • Treatments of 5, 10 and 20% sludge application by volume, 402, 805 and 1,610 g/plant • Mechanically mixed shrimp sludge and potting soil mix (concrete sand, mulch, vermiculite) • Randomly transplanted and arranged 28 ‘Roma’ tomato starts in a greenhouse, one plant per pot • Each plant received 4 L of water daily, over four applications by drip irrigation • Response measured in mass of tomatoes produced

4. Statistical Analysis • One-way ANOVA of total mean mass of tomatoes per plant for each treatment

6. Shrimp Sludge Characteristics Total N, PO4-P and K show total plant macronutrients NO3-N, Olsen P and soluble K show plant available nutrients EC provides a measurement of soil salinity

10. Results

11. Treatment Tomato Mass (g/plant) SEM 0% (Control) 39.2a 11.54 5% 402 g/plant 65.1a 11.14 10% 805 g/plant 141.1b 20.73 20% 1,620 g/plant 113.6b 19.9 Tomato Production Different superscripts indicate a significant difference, p<0.05

12. Conclusions • Applications of 10% and 20% increased plant production • Suggests land application will benefit crop production while providing a disposal mechanism • Large, field scale application experiment suggested to verify results • Soil salinity must also be monitored, given high evaporation rates • Sludge is highly variable, depending on pond management